What Is Bioengineering?

Biological engineering (a. k. a. biosystems engineering, bioengineering) is any type of engineering–for example, mechanical engineering–applied to living things.

Examples: Aquaculture, Biosensors, Bio-based materials, Biomaterials, Industrial fermentation, Industrial enzymatic reactions, Production and purification of biopharmaceuticals, Advanced life support system, Artificial biospheres eg. Biosphere 2, Animal locomotion.

Bioengineers are concerned with the application of engineering sciences, methods, and techniques to problems in medicine and biology. Bioengineering encompasses two closely related fields of interest: the application of engineering sciences to understand how animals and plants function; and the application of engineering technologies to design and develop new devices, including diagnostic or therapeutic instrumentation, or the formulation of synthetic biomaterials, the design of artificial tissues and organs, and the development of new drug delivery systems.

Bioengineering is the application of the principles of engineering and natural sciences to tissues, cells and molecules. Closely related to this is biotechnology, which deals with the implementation of biological knowledge in industrial processes. Applications from both fields are widely used in medical and natural sciences and also in engineering.

What is bioengineering?

There are as many definitions of Bioengineering as there are groups working in the field. In the area of health, the US National Institute of Health formed a Bioengineering Definition Committee that released the following preamble and definition on July 24, 1997:

Preamble

Bioengineering is rooted in physics, mathematics, chemistry, biology, and the life sciences. It is the application of a systematic, quantitative, and integrative way of thinking about and approaching the solutions of problems important to biology, medical research, clinical proactive, and population studies. The NIH Bioengineering Consortium agreed on the following definition for bioengineering research on biology, medicine, behavior, or health recognizing that no definition could completely eliminate overlap with other research disciplines or preclude variations in interpretation by different individuals and organizations.

Definition

Bioengineering integrates physical, chemical, or mathematical sciences and engineering principles for the study of biology, medicine, behavior, or health. It advances fundamental concepts, creates knowledge for the molecular to the organ systems levels, and develops innovative biologics, materials, processes, implants, devices, and informatics approaches for the prevention, diagnosis, and treatment of disease, for patient rehabilitation, and for improving health.

If we ignore the obvious health focus in the NIH definition, it is clear that bioengineering is concerned with applying an engineering approach (systematic, quantitative, and integrative) and an engineering focus (the solutions of problems) to biological problems.

BIOENGINEERING is the application of engineering design and technology to living systems. Any living system. While for the majority, the obvious, and perhaps justifiably, the most important, living system is the one walking upright and registered with a doctor, many bioengineers work in breweries, drug companies, farming and the environment. With plants, insects and fungi.

The discipline is thus not confined to the design and production of Medical Devices, but encompasses any situation where technology must interface with a living system.

Bioengineers have to be mentally flexible, willing to adopt and adapt techniques from other industries, and to work with people from a wide range of disciplines.

As an example of the art, consider a Kidney Machine and the sub-systems which go to make up this example of vital life support equipment:

Water treatment and purification. Heating and temperature control for pasteurisation and patient comfort. Measurement systems for flow and pressure, electrolytes. Alarm systems for all vital parameters. Data collection and processing. Ergonomics Electrical Safety

Clinical Measurement represents a large sector within the field. Modern sensor technology permits the measurement of parameters for aiding diagnosis and monitoring therapy to an extent impossible to imagine even ten years ago. Biomechanical engineers are designing tools enabling surgeons to perform sophisticated “keyhole” surgery, while device technology and computer complexity is advancing fast enough to bring the clinician’s wildest aspirations within reach.

Bioengineering is what you do with biotechnology. Biotechnology is what you get from studying and learning how to manipulate biology. It has been known for more than a hundred years that life is basically a machine which takes in fuel and performs work. This machine is remarkable in that it arose through variation and selection from a very primitive self replicating molecule. The closest analogue of this molecule present in our contemporary biology is the ribosome. It has been found that this ribosome consists, in part, of a strand of RNA. Inside the nucleus of a human cell there are twenty two pairs of chromosomes and either another pair or two different. These, as you are probably tired of hearing, are mostly DNA. In our cells is also an organelle which is called a mitochondria. This organelle was, once, a separate life-form. It evolved separately from the type of cells that make up most of our body and its internal structure is significantly different from the cell it is now a part of. These mitochondria have their own DNA but have come to live within our cells as symbiotes. These scientific findings will underlie the rest of this essay.

What is the significance of DNA? It’s just a molecule, right? Yes it is. That is exactly what it is. It has no magical properties whatsoever. Science fiction notions of being able to mutate an adult human by changing their DNA to that of another species, perhaps, would not have any morphological change on the person because there is not, yet at least, a gene that can reshape bone. Most random gene changes result in some kind of disease such as cancer. This should seem weird to you. I am talking about changing a DNA molecule but I’m not suggesting that it becomes anything other than a DNA molecule. I mean changing your garden variety molecule by changing even a single bond usually makes something totally different. What is DNA that it is different? For one thing DNA is actually a family of molecules composed of adenine, thymine, cystine, and guinine. RNA uses a molecule called uracil in place of thymine. A strand of DNA is a linked chain of any number of any combination of those four “base pairs”. When we talk about modifying DNA we are talking about rearranging sequences of base pairs.

The DNA molecule serves a function no different from the hard drive on your computer. It stores information. The three billion year history of the DNA molecule is a testament to its effectiveness as a storage medium. RNA is more like your computer’s working memory. It is natural to consider the act of designing a DNA strand in the same way we would consider the act of writing a program for a computer. A bioengineer, or as it was put in Blade Runner, a genetic designer, is a DNA programmer. I am trying to express these ideas in these terms because a certain mysticism has arisen around DNA that needs to be dispelled before we can consider the questions of what we might be able, or want, to do with our newfound ability to manipulate it.

There are a great many who are so shocked by these ideas that they immediately rush to outlaw research as soon as they are informed of its possibility. These feelings of fear and anxiety extend to many areas of reproductive medicine and general angst about self-modification. All these things boil down to one simple fact. People are afraid to acknowledge what they are. If they ever dared, they may have tried to feel their bodies as being made of cells and molecules and existing in a void of randomly moving gasses and a hard empty floor. They might be able to open their eyes wide enough to see the functioning of their minds and understand that it is merely a computation running on some very impressive but ultimately kludged together hardware. I do this from time to time to keep my bearings. It is not a pleasant experience. Throughout history this truth has been an inevitability. No matter how keen your vision is there was nothing you could do about it. Being, quite literally, helpless people constructed fictions about souls, gods, and the tooth fairy and just about any other entity or idea that people tend to bring into these debates. These are beloved lies.

Until now, they’ve been the lies that have allowed us to live. With bioengineering we will have the power to change that. We will soon have complete power. You no longer have to be afraid of the beat of your heart knowing that each one has a number and the number is counting downward. You no longer have to feel alone in your own skull. You can have a neural interface. You will no longer need to fear crippling injury, it can be repaired. You will be able to live for years in zero gravity in perfect health. You will be able to tolerate significant doses of radiation. You will be able to metabolize poisonous chemicals. You will never suffer a serious illness. These are the possibilities. All we, as a people, need to do is face our fears with the sword called Biotechnology. Lies need no longer be our only shield.

In the past all changes to your body were either impossible or irreversible. To live a long and healthy life one had no choice but to take the best care possible of their bodies so that it would remain healthy for as long as possible. For this reason the body became an object of worship. Something that deserves special consideration above all others. While the health and safety of our embodiment will always be a concern it is no longer necessary to treat it as holy and untouchable. It is foreseeable that people might be struck by some fancy or other that they want to follow for a few years. These people will no longer be forced to consider their long term health because it will be taken care of by advanced medical nanotechnology which will be able to implement or reverse just about any change.

Considering that there is nothing in the universe that has any opinion one way or another what we do to ourselves we might just as well do whatever we want. All of you have are your desires and your tools. It would be a tragedy in more ways than one if the conservative elements in our psyches strangle this one eighty year opportunity we are given to do what ever we want with our body. There is no such thing as a crime against one’s self and nothing should be considered as such. We live in a free universe if not in a free country. So to these conservative voices I ask “why not?”

A Living Future With Room For Everyone

On the other extreme there is a faction in the singularitan community which thinks that people who wish to use biotechnology are, to pick a word, backwards. They think that the singularity means that their nanoscale robots are inherently better than the biological cells which have served us from, practically, the beginning of time merely because they happen to process information in a slightly different way which would allow them to be faster and more vicious in the war of evolution. Although their machines are made out of the same atoms that compose the bulk of our own bodies, they have told me that their “machine phase life” will quickly supersede biological life. They wish to plunge the universe into a new epoch of life which they will direct from their own computer simulations as uploads. To these people my question is WHY?

Creating a “doom goo” is behavior fit for a script kiddie, the lowest grade of computer abusers. It would be no different from the Mac users getting their final revenge on all the PC users. Civilized people who choose to use ultra-technologies should have the, well, civility to respect the people who want to take a little more time to figure out what they want to be or to be something completely different. It is wrong, in every way, to unleash such destruction on people who only wish to remain human regardless how superior the replacements are. The only reason we develop technology at all is to make our own, human, lives better. Lets take these nanotechnologies and let them become our symbiotes just as the mitochondria are. Lets build a massively powerful computer not to run simulations of our brains but rather simulations of our proteins. Let us apply bioengineering to our own cells to make the very stuff of our body better than it has ever been before.

The ultimate use of nanotechnology is in our own cells. We, ourselves, in our present incarnation can take advantage of everything I am talking about here (except, perhaps, certain mental upgrades). We will start with the cell and reengineer it from the first atom. We will use nanites, DNA, hydrocarbons, or whatever else to make a stable, resilient, and vital whole. Our new biologies will be limited only by our imaginations and the laws of physics. These bold dreams excite only ridicule in the most radical computronium-heads. The universe is billions of light-years across and they don’t see any room in it for us. In my article on the singularity I mentioned the use of legal and military controls to preserve personal liberties. This is one of the most important areas that this force should be applied. The singularity is a neutral thing. It can be spectacularly good if it can be kept under human[oid] control. It has an equal potential to be unimaginably bad for everything we, today, call living things.

As radical and audacious as my ideas about cyborgs and bioengineering may seem they are, in the grand scheme of things, quite conservative and an appropriate mean between the two extremes. Lets bring on the future but lets do it with our eyes open and our own interests in heart and mind.

Science, Technology, and the Art of Design

Body blueprints are passed around all the time by their own natural functions. Only in the last fifty years we have been able to appreciate sexual reproduction as an information exchange. In the muck at the bottom of ponds you can find that the bacteria that live there have established a commune of sorts in which DNA is passed back and shared among them. Things won’t be so easy-going with the blueprints of the new cellular structure I mentioned above because of the intense effort required to produce them. I think that because of this and the importance of a fair and equal access that the core sciences and technologies behind cyborg biologies, and everything else for that matter, should forever be kept in the public domain.

The people who think it would be only fair that the people who put the direct effort into the direct design work should receive a patent for a few years in order to recoup their costs. Lets think about this. How did these people get the scientific knowledge about DNA and the proteins? Where did they get their computers? Who provided the computing services? How did they figure out how to program the AI that helped them organize the gigabytes of data that is required to build a cyborg and its accompanying technologies? The answer to all of these is millions of people. More than a million biologists and chemists made significant contributions to the project. Every single person who has purchased a computer has helped fund further research and industrial development that made the project possible. Hundreds of thousands of people contribute their spare computer cycles to on-line projects such as folding@home which studies the very proteins that are the subject of this essay. Their AI wasn’t the result of some eureka moment but the culmination of five thousand years of mathematical research. They also owe debts to the neurologists and psychologists who have spent the last two hundred years mapping the brain.

To take all this effort from practically the entire human race and then try to sell it back to us at a price is outrageous. As I mentioned above, DNA and any nanotech design is merely data which, in fact, can be stored on a hard disk. This means that you can download it to your hard disk from the internet. As the science of cellular biology is completed the finished proteins and core science should be made available on the internet to anyone who wants it. This might not seem very useful to you as an individual. I will return to that shortly.

This isn’t to say that all data should be made available. There is a difference between the right to know everything about a brick and the right to know how to build a luxury home. Unlike the basic science and technology which is our birthright the actual integrated designs of original bodies are a form of art. The service of designing a body is one that should be paid for. Designers work alone from the common knowledge and create something new that is from themselves and hence worth being sold. More generally it is best that designs be kept private so that there will, necessarily, be many more of them and greater variation. It is not at all my goal for anyone else to even be the same species as me except, perhaps, my offspring. Others might say that it is always best to be an upload running on computronium. Some say that doing anything at all to one’s self is wrong. Aside from my own personal desires, my goal is to defend everyone’s right to be what they want to be. I want the singularity to be an enabler of deep personal desires rather than the realization of some grand master plan. The latter would be an absolute horror.

One of the concerns that might be raised regarding the notion of keeping designs proprietary is how all these, potentially radically, different breeds of people will interact in society. A major concern will be whether these new species will be able to form families and have children like humans do. This is not a terrible concern as there will be the possibility of creating offspring from scratch. This may not be the most reliable means as one would prefer not to abandon the old way as a fallback. With intelligent machines it should be possible to take even the most different designs and to generate some integration of the two. This function can be integrated into the body of a cyborg female or hermaphrodite. With these two functions of differentiation through separate design and intelligently controlled recombination the mechanism of evolution will continue into the future but not in its old merciless clothes.

Hyper-Evolution

The process of evolution is about to be changed radically. In the past evolution proceeded on the basis of genes that are passed from parent to offspring and changes that arise from semi random mutations. In the future traits will be passed in the form of binary strings and edited by the intelligent design of conscious minds. Ever since we gained the ability to talk our minds have had the ability to create, transmit, and process things that are sometimes called memes. A meme shares many of the same properties as genes. The period of time between the creation of language some 40,000 years ago and these decades in which we live today when the genome was cracked and will soon be the subject of arbitrary manipulation can be understood as a process by which memes have arisen from genes and now are in a position to replace them. This replaces the evolution of genes with what I call the hyper-evolution of memes.

I mean hyper-evolution to mean nothing more or less than evolution by conscious design. In terms of biology alone the coming years promise to be very chaotic. The new reflexive relationship of an individual to his own genetic makeup will result in a dynamic feedback loop which will significantly alter the historic patterns and equilibrium. It is reasonable to assume that after a few decades or centuries the process will result in some new stable equilibrium. It is very difficult to speculate on the dynamics of such a process as there is little historic data to fall back upon. The closest analogue might be the evolution of the automobile or of computer software especially open source software.

Hyper-evolution is very good news for individuals because it disconnects the process of evolution from the lives and deaths of individual bodies. As Dawkins said, a chicken is an egg’s way of creating another egg. With nano-enhanced cells we can disconnect our lives from the process which selects our traits. The classical idea of eugenics can be completely discarded. It is no longer necessary to make sure that people have the right genes at birth because they can be changed later in life. The easiest way to make such a change would be to add the nano symbiote to the zygote (a fertilized egg). These nanites could be activated at any time in the individual’s life to whatever effect desired. Retrofitting an adult individual with these will be immensely more difficult but not altogether inconceivable.

Above all, evolution is renown for its cruelty. It “de-selects” traits by killing individuals. Proposals for directed evolution from Plato forward have been little better. Because hyper-evolution has the potential to select and propagate traits without the necessity of creating and destroying individuals. This means that the way we contemplate the population dynamics of a hyper-evolutionary system vary differently from the traditional. Instead of considering the population of chickens in the universe we consider the populations of memes in the hosts that are capable of sustaining them. The fitness of a given meme is therefore dictated by the probability of it being chosen by a given host and by how well it serves that host in order that it may be propagated. In this way the memes that we can transmit through computer networks have the relationship to us as DNA does to a cellular membrane which houses it.

To us, it means that the race of competition between individuals will be over as the war of replicating memes has moved to a new level. We have the prospect of an eternity of peace, health, opportunity, and unlimited choice. A threat to this is the observation that evolutionary forces might interact with government structures as a means to self-propagation. The value of personal freedom must be maintained above all others.

You can be bio-engineered to be, practically, immortal. Age will mean nothing to you and accidental death won’t be nearly as great a risk as it is today as your body will be more resistant and resilient to all but the most grave injuries. The dynamics of evolution have made genetics extremely good at constructing bodies. Unfortunately there was no selective pressure pushing for better mechanisms of maintenance and repair. In the future not only the more ambitious among us but also the very memes that will specify the fabric of our bodies will select for the most stable possible host. You may not choose to take advantage of this for yourself but some will.

There is nothing magical about the elixir of life that’s coming to a health food store near you. It will merely be a type of nanotech which will be designed to repair and, occasionally, tweak the designs of your cells. In this manner your body can be perpetuated indefinitely. There are no catches, no hidden costs, you won’t even have to sell your soul. You will, if you choose to, simply continue to live as long as you like. You will not be constrained to a decrepit old body either. Your nanites can restore you to any appearance or level of health you desire. A few years after this is brought to market the cost will come down so low that your next body could be cheaper than the car you might have bought last month.

Some people object to immortality based on the idea that they should make room for the next generation. That’s not a problem because soon we will be able to emigrate to other planets. You could become a homesteader on Mars. The question of whether some people should seek immortality is not an issue because it would be highly unethical to kill someone who wants to live. The problem arises in the cultural conflicts between the community of immortalists and the traditionalists. The key is tolerance on both sides.

Each person must make their own choice about whether to try for immortality. There shouldn’t even be a universal code of all bodies must be immortal unless otherwise specified. As long as the choice remains open there is no problem. We can think of lives like rockets. Every once and a while we design one, haul it out to the pad and hit the big red button. In many cases these rockets have exploded into flames, never getting off the launch pad. Others launch, make it all the way to the edge of space, and do whatever small mission is theirs and come down without ever reaching orbit or orbiting for only a few years before coming down. Sometimes they go up there, serve out their useful life and then continue to operate for many decades, sometimes exceeding their intended lifespans by a large multiple. In 1974 the Amateur Satellite service (AmSat) launched the seventh in their Oscar series. It continued to work over the next seven years until the battery shorted out. Sometime in the two decades that followed the short was cleared by the constant flow of electricity. Today it only needs the sun. Its beacon is still loud and its transponders open and clear after having gone around the planet some 127,000 times.

Likewise some of us will live to see the year 3,000 and some won’t. There is no imperative to change the natures of the people who simply don’t want to live so long just as there is no need to set some expiration date for those who do. Nobody has yet lived past 135 or so. Reports of longer lifespans are dubious. We can’t say we know for sure what it really means to live so many years. We can say with confidence that we can make a humanoid body that doesn’t grow old. We cannot say what will happen to the mind over a long period of time. Studies have shown that the brain looses a significant amount of plasticity during adolescence and the slowness of the elderly to adopt new ideas is almost a cliché. If you think about it too hard you start questioning the meaning of life and all the other fundamental questions of existence. In the future these questions will no longer be abstract philosophy but matters of practical importance.

Let’s say that you have decided to choose immortality and you are now 120 years old. The world is changing and it is becoming clear, even to you, that you will need to adapt to keep up. In theory it will be possible to use neural stem cells to restore the plasticity of youth. When you do this you discover that while this does, indeed, restore your ability to learn new skills and ways of thinking it overwrites parts of your mind so that your memories of the past tend to be less clear and your personality starts to shift towards the modern norm. You feel that you have become a new person through biotechnical intervention. While your body and mind remain continuous your inner self has been changed in such a way that it seems, to everybody, that the old you is dead.

Another approach to solving this problem would be to gradually replace your brain, as it deteriorates, with a physical implementation of the best AI around. This new brain works very differently from your original. You chose it because it also performs about a million times better in every way and offers a number of interesting extended capabilities that lie outside of the scope of this essay. While such a brain would be able to function at its peak indefinitely into the future there is a serious question of whether your mind can do like a hermit crab and move into the new host. It can be foreseen that in the protracted future people who choose not to upgrade their original brains significantly will be at a serious disadvantage. Only when we understand the mind well enough to construct artificial intelligences will we be able to begin to answer these questions.

An Invitation To Dream and Live

The bulk of this essay has been about the basic concepts and issues surrounding bioengineering. I could just tie it up with a nice conclusion. If I did that I would give up the chance to share some of the hope I have for this coming age. Bioengineering didn’t just arise out of many diverse human activities it can also serve people in ways hardly even imagined now. There is no reason to be ashamed of wanting to change, even if it is into something very different. It is a wonderful thing to have desires, even crazy ones. Bioengineering will enable us to go places that our current bodies can’t even survive such as the oceans or worlds that receive too much radiation for our current forms. Even if your interests are much more personal bioengineering is still the right tool.

It is time to begin dreaming like children again because it is our dreams that are the fuel of all adventures. The times ahead will be both strange and wonderful. With hard work and constant vigilance far more dreams than nightmares will come true. The singularity itself is a nexus of dreams and terrors. To make it happen for us we must invest our dreams in it with the knowledge that our hard work will bring them true. We can make it wonderful for us and everyone.

If, perchance you are not yet inspired by my presentation or simply don’t want to change your body in any significant way I have perfect sympathy for you and will respect you always. If you think that there is something inherently wrong with what I am talking about here and think that these developments must be halted I ask you to reconsider. Without considering any modification to yourself, think of all the costs of maintaining your current body. Consider the prescriptions, the doctor’s appointments, and the costs of a visit to a hospital should you run into some misfortune. Now think about the most advanced hospital in the world staffed with the best doctors in the world. Think of a hospital which can provide you with every treatment or medicine you could ever need or want. Now imagine that it only cost you five dollars per visit. This is not a joke, this is possible.

Consider the technologies of AI, Nanotechnology, and Biotechnology. Now imagine all these wonders integrated into a single pod which you could purchase for as little as $2,000. Medicine can be automated, completely. You can purchace one of thes for yourself or your family and only need to pay for the raw molecules required to construct the supplies it needs. This pod will contain within it a mind a hundreds times smarter than the most brilliant physician that ever lived and completely devoted to your service. Its internal systems will be able to integrate new procedures and inventions simply by downloading the blueprints from the internet and performing an auto-upgrade. You will be free of the medical establishment entirely. Such pods should only be regulated to the minimal extent required to ensure the accountability of their designers for any malfunction.

What is Bioengineering?

Bioengineering combines the analytical and experimental methods of the engineering profession with the biological and medical sciences to achieve a more detailed understanding of biological phenomena and to develop new techniques and devices.

Environ Sci Technol, 2002 Jun 15, 36(12), 2572 - 80
Charge effects in the fractionation of natural organics using ultrafiltration; Schafer AI et al.; Comparison of two commonly used techniques for molecular weight determination of natural organics, ultrafiltration (UF) fractionation and high-performance size exclusion chromatography (SEC), shows that neither technique gives absolute measures of molecular weight . Investigations of International Humic Substances Society standard humic and fulvic acids as well as natural organic matter concentrated from surface freshwaters show that charge effects and solution conditions are important in both SEC and UF fractionation with various components of the natural organics being affected differently . Membranes with a smaller molecular weight cutoff (MWCO) produce permeates with a lower UV/DOC ratio, suggesting that the more aromatic components of natural organics are removed by the lower molecular weight cutoff membranes . Variation in ionic strength has little effect on the rejection of humic acid fractions but does significantly influence the rejection of low molecular weight acids . pH and organic concentration do not affect DOC rejection significantly over the pH range of 4.5-10 and the DOC concentration range of 15-60 mgL(-1) . These results indicate that UF should not be applied for quantitative “size” analysis unless performed under well-defined conditions . If performed under conditions appropriate to water treatment, UF fractionation can give information of direct applicability to treatment such as the MWCO required to achieve significant organics removal.

Nephrol News Issues, 2001 Jan, 15(2), 27, 30, 33 - 6
Treating and monitoring water for dialysis in Europe; Lindley EJ et al.; The quality of water used for dialysis is not subject to any mandatory regulations in most European countries . A survey of haemodialysis facilities in 14 countries carried out by the European Dialysis and Transplant Nurses Association/European Renal Care Association (EDTNA/ERCA) showed that the majority of centres aimed to meet the requirements of the European Pharmacopoeia, but only 50% carried out tests to check compliance . The wide variation in policies for maintaining and monitoring the equipment and the distribution system indicates that guidelines for water treatment are urgently needed in Europe.

Clin Microbiol Rev, 2002 Jul, 15(3), 506 - 26
Legionella and Legionnaires’ disease: 25 years of investigation; Fields BS et al.; There is still a low level of clinical awareness regarding Legionnaires’ disease 25 years after it was first detected . The causative agents, legionellae, are freshwater bacteria with a fascinating ecology . These bacteria are intracellular pathogens of freshwater protozoa and utilize a similar mechanism to infect human phagocytic cells . There have been major advances in delineating the pathogenesis of legionellae through the identification of genes which allow the organism to bypass the endocytic pathways of both protozoan and human cells . Other bacteria that may share this novel infectious process are Coxiella burnetti and Brucella spp . More than 40 species and numerous serogroups of legionellae have been identified . Most diagnostic tests are directed at the species that causes most of the reported human cases of legionellosis, L . pneumophila serogroup 1 . For this reason, information on the incidence of human respiratory disease attributable to other species and serogroups of legionellae is lacking . Improvements in diagnostic tests such as the urine antigen assay have inadvertently caused a decrease in the use of culture to detect infection, resulting in incomplete surveillance for legionellosis . Large, focal outbreaks of Legionnaires’ disease continue to occur worldwide, and there is a critical need for surveillance for travel-related legionellosis in the United States . There is optimism that newly developed guidelines and water treatment practices can greatly reduce the incidence of this preventable illness.

Water Res, 2002 Apr, 36(8), 1939 - 46
The leaching of inorganic species from activated carbons produced from waste tyre rubber; San Miguel G et al.; Waste tyre rubber can be used as a precursor for the production of high quality activated carbons . However, there is concern that inorganic impurities present in the rubber feed may restrict their use in liquid phase applications with high purity requirements . This paper presents an investigation of the presence and the leaching of inorganic species from activated carbons derived from waste tyre rubber . For the purpose of this work, a number of carbons were produced, characterised for their BET surface area and analysed for their inorganic composition . Subsequently, a number of tests were performed to evaluate the leaching of different inorganic species into solution at various pH values and carbon doses . Results showed that rubber-derived carbons contained elevated concentrations of sulphur and zinc, as well as traces of other metals such as lead, cadmium, chromium and molybdenum . Inorganic levels were significantly affected by production conditions, particularly degree of carbon activation and the nature of the gasification agent . However, leaching tests showed that the availability of these species in neutral pH conditions was very limited . Results demonstrated that, when using carbons doses comparable to those employed in water treatment works, only sulphur levels exceeded, in some occasions, health based quality standards proposed for drinking water.

Appl Environ Microbiol, 2002 Jul, 68(7), 3293 - 9
Potential repair of Escherichia coli DNA following exposure to UV radiation from both medium- and low-pressure UV sources used in drinking water treatment; Zimmer JL et al.; The increased use of UV radiation as a drinking water treatment technology has instigated studies of the repair potential of microorganisms following treatment . This study challenged the repair potential of an optimally grown nonpathogenic laboratory strain of Escherichia coli after UV radiation from low- and medium-pressure lamps . Samples were irradiated with doses of 5, 8, and 10 mJ/cm(2) from a low-pressure lamp and 3, 5, 8, and 10 mJ/cm(2) from a medium-pressure UV lamp housed in a bench-scale collimated beam apparatus . Following irradiation, samples were incubated at 37 degrees C under photoreactivating light or in the dark . Sample aliquots were analyzed for up to 4 h following incubation using a standard plate count . Results of this study showed that E . coli underwent photorepair following exposure to the low-pressure UV source, but no repair was detectable following exposure to the medium-pressure UV source at the initial doses examined . Minimal repair was eventually observed upon medium-pressure UV lamp exposure when doses were lowered to 3 mJ/cm(2) . This study clearly indicates differences in repair potential under laboratory conditions between irradiation from low-pressure and medium-pressure UV sources of the type used in water treatment.

Environ Technol, 2002 Apr, 23(4), 453 - 65
Purification of pulp and paper mill effluent using Eichornia crassipes; Yedla S et al.; Konark Pulp and Paper Industries Private Limited is a medium size industry producing 1600 m3 of wastewater a day . The existing water treatment system of the industry was found to be ineffective both in performance and economy . In the present study, a new system of treatment has been developed using water hyacinth Eichornia crassipes, coagulation by lime and alum, followed by rapid sand filtration . The performance efficiency of each unit viz . Eichornia treatment; coagulation with lime, with alum, and with lime:alum combinations, and filtration was studied . Water quality parameters considered were Biological Oxygen Demand, Chemical Oxygen Demand, Dissolve Oxygen, Total Dissolved Solids, turbidity, percentage transmission, and water colour . Based on the individual performance of each unit, a continuous system has been designed and was tested . The new system of treatment could treat the wastewater to the discharge standards and also was found economically feasible . Testing culture of fish (tilapia) proved that the treated water could be safely discharged into natural waters . All fish tested, survived and remained healthy throughout the period of testing . Culture of fish further improved the water quality.

Water Sci Technol, 2002, 45(9), 205 - 11
Real-time water quality monitoring and regression analysis to estimate nutrient and bacteria concentrations in Kansas streams; Christensen VG et al.; An innovative approach currently is underway in Kansas to estimate and monitor constituent concentrations in streams . Continuous in-stream water-quality monitors are installed at selected U.S . Geological Survey stream-gaging stations to provide real-time measurement of specific conductance, pH, water temperature, dissolved oxygen, turbidity, and total chlorophyll . In addition, periodic water samples are collected manually and analyzed for nutrients, bacteria, and other constituents of concern . Regression equations then are developed from measurements made by the water-quality monitors and analytical results of manually collected samples . These regression equations are used to estimate nutrient, bacteria, and other constituent concentrations . Concentrations then are available to calculate loads and yields to further assess water quality in watersheds . The continuous and real-time nature of the data may be important when considering recreational use of a water body; developing and monitoring total maximum daily loads; adjusting water-treatment strategies; and determining high constituent concentrations in time to prevent adverse effects on fish or other aquatic life.

Chemosphere, 2002 May, 47(7), 711 - 6
Comparison of modified montmorillonite adsorbents . Part I: Preparation, characterization and phenol adsorption; Jiang JQ et al.; This study concerns with the development of modified montmorillonites as adsorbents for water treatment . Polymeric aluminium and iron intercalated forms of montmorillonites have been prepared in the absence and presence of an alkylammonium cationic surfactant (Hexdecyl-trimethyl-ammonium bromide, HDTMA) . Montmorillonites intercalated with polymeric Al, Fe, Fe/Al (2:1 Fe to Al ratio in solution), possess large N2 Brunauer-Emmett-Teller (BET) surface areas . XRD data also shows trace amounts of illite and plagioclase within the clay materials . Montmorillonites intercalated with HDTMA, polymeric Fe/HDTMA, polymeric Al/HDTMA and polymeric Fe/Al/HDTMA (1:1 metal to surfactant molar ratio in solution) undergo some losses of N2 BET surface areas . Preliminary adsorption studies on phenol have shown that polymeric Al/HDTMA- and HDTMA-only-modified montmorillonites possess a good affinity for phenol, whereas the polymeric Al/Fe modified- and starting montmorillonites have little affinity for phenol adsorption.

Chemosphere, 2002 May, 47(7), 667 - 86
Trichloroacetic acid in the environment; McCulloch A; Suppositions that the trichloroacetic acid (TCA, CCl3C(O)OH) found in nature was a consequence solely of the use of chlorinated hydrocarbon solvents prompted this critical review of the literature on its environmental fluxes and occurrences . TCA is widely distributed in forest soils (where it was rarely used as an herbicide) and measurements suggest a soil flux of 160 000 tonnes yr(-1) in European forests alone . TCA is also produced during oxidative water treatment and the global flux could amount to 55 000 tonnes yr(-1) (from pulp and paper manufacture, potable water and cooling water treatments) . By contrast, the yields of TCA from chlorinated hydrocarbon solvents are small: from tetrachloroethene 13 600 tonnes yr(-1) and from 1,1,1-trichloroethane 4300 tonnes yr(-1) on a global basis, at the atmospheric burdens and removal rates typical of the late 1990s . TCA is ubiquitous in rainwater and snow . Its concentrations are highly variable and the variations cannot be connected with location or date . However, there is no significant difference between the concentrations found in Chile and in eastern Canada (by the same analysts), or between Malawi and western Canada, or between Antarctica and Switzerland, nor any significant difference globally between the concentrations in cloud, rain and snow (although local enhancement in fog water has been shown) . TCA is present in old ice and firn . At the deepest levels, the firn was deposited early in the 19th century, well before the possibility of contamination by industrial production of reactive chlorine, implying a non-industrial background . This proposition is supported by plume measurements from pulp mills in Finland . TCA is ubiquitous in soils; concentrations are very variable but there are some indications that soils under coniferous trees contain higher amounts . The concentrations of TCA found in plant tissue are region-specific and may also be plant-specific, to the extent that conifers seem to contain more than other species . TCA is removed from the environment naturally . There is abundant evidence that soil microorganisms dehalogenate TCA and it is lost from within spruce needles with a half-life of 10 days . There is also recent evidence of an abiotic aqueous decarboxylation mechanism with a half-life of 22 days . The supposedly widespread effects of TCA in conifer needles are not shown in controlled experiments . At concentrations in the needles of Scots pine similar to those observed in needles in forest trees, changes consequent on TCA treatment of field laboratory specimens were almost all insignificant.

FEMS Microbiol Rev, 2002 Jun, 26(2), 113 - 23
Risk and control of waterborne cryptosporidiosis; Rose JB et al.; Cryptosporidium remains at the forefront of studies on waterborne disease transmission and abatement . The impact of environmental land use patterns which contribute animal and human waste, climatic precipitation leading to a strong association with outbreaks, and community infrastructure and water treatment are now recognized as contributing factors in the potential for waterborne spread of the protozoan . Advances in detection methodologies, including the ability to genotype various strains of this organism, have shown that human wastes are often the source of the contamination and cell culture techniques have allowed insight into the viability of the oocyst populations . Currently water treatment has focused on UV and ozone disinfection as most promising for the inactivation of this protozoan pathogen.

Sci Total Environ, 2002 Apr 22, 289(1-3), 225 - 35
Correlation of musty odor and 2-MIB in two drinking water treatment plants in South Taiwan; Lin TF et al.; Possible odor groups and intensity, and seasonal effects were elucidated in two representative water treatment plants (WTPs), Feng-Shen and Gun-Shi, in southern Taiwan . The flavor profile analysis (FPA) was employed to determine the odor groups for the source water, while a chemical analysis, solid-phase microextraction (SPME) coupled with a gas chromatograph and mass spectrometric detector (GC/MSD), was used to concentrate and subsequently analyze the corresponding water samples . FPA results show that fishy and musty odors were the two major odor groups in the source water . Results of chemical analysis showed that 2-methyl-isoborneol (2-MIB) was present in the source water . The correlation between 2-MIB concentration and the FPA intensity of musty odor was compared with the dose-response curve generated in the laboratory by the FPA panelists . The experimental data from the two water treatment plants follow the calibration curve closely, indicating that the musty odor of the two source waters were most likely contributed from 2-MIB . In addition, there is good correlation between logarithmic 2-MIB concentration and water temperature, substantiating the importance of seasonal effect . Although approximately 40-50% of 2-MIB removal was found in the treatment trains for the two WTPs, only an approximately 0.3 FPA intensity scale of reduction was expected.

Huan Jing Ke Xue, 2002 Mar, 23(2), 45 - 9
{Membrane filtration characteristics and its influencing factors in coagulation-microfiltration combination process for water purification}; Mo L et al.; A coagulation-microfiltration combination process was used to treat micro-polluted raw water in the intermittent operation mode . The effect of the operational parameters such as filtration time and aeration intensity, on the membrane filtration characteristics was investigated . An indicator J/p, defined as flux per unit pressure, was employed . At all the experimental conditions, J/p always fell down fast at first owing to membrane fouling, and then decreased slowly . But the initial decreasing rate and relative stable value of J/p in the latter period depended on the different operational parameters . J/p was greatly influenced by the filtration time, then the ratio of the filtration time to the ceasing time . Under the condition the filtration time was shortened by 1/2, the flux will increase by two times; when the ratio of filtration time/ceasing time was shortened, the flux was increased by only 50% . Higher J/p value could be achieved at the filtration time of 15 min and the ratio of filtration time/ceasing time of 3.8 . Increased aeration intensity could enhance J/p to some extent . In the experiments, when the aeration intensity was increased from 2 to 4 m3/h, the membrane permeability was increased by about 15%; and the membrane permeability would not increased if the aeration intensity was continuously increased to 6 m3/h . Primary inorganic elements on the membrane surface at the present experimental condition were found to be Si and Ca from the element analysis.

J Environ Sci Health A Tox Hazard Subst Environ Eng, 2002, 37(4), 737 - 43
Reducing environmental emissions in tanneries; van Groenestijn JW et al.; Tanning, in particular chrome leather production, is still characterised by an inefficient use of raw material and the production of highly polluted wastewater and solid wastes . A part of the emissions can be prevented by introducing clean tanning technologies, the remaining emissions can be treated . Clean production technologies and waste (water) treatment technologies should have a designed complimentarity . Anaerobic wastewater treatment with recovery of sulfides, sulfur and energy (biogas) is a cornerstone in such integral clean chrome leather technology.

J Environ Sci Health A Tox Hazard Subst Environ Eng, 2002, 37(4), 707 - 13
Ozonation of the purified hydrolyzed azo dye Reactive Red 120 (CI); Zhang F et al.; The combination of chemical and biological water treatment processes is a promising technique to reduce recalcitrant wastewater loads . The key to the efficiency of such a system is a better understanding of the mechanisms involved during the degradation processes . Ozonation has been applied to many fields in water and wastewater treatment . Especially for effluents of textile finishing industry ozonation can achieve high color removal, enhance biodegradability, destroy phenols and reduce the COD . However, little is known about the reaction intermediates and products formed during ozonation . This work focuses on the oxidative degradation of purified (>90%), hydrolyzed Reactive Red 120 (Color Index), a widely used azo dye in the textile finishing processes with two monochlorotriazine anchor groups . Ozonation of the dye in ultra pure water was performed in a laboratory scale cylindrical batch reactor . Decolorization, determined by measuring the light absorbance at the maximum wavelength in the visible range (535 nm), was almost complete after 150 min with an ozone concentration of 12.8 mg/l . The TOC/TOC0 ratio was about 74% and the COD was diminished to 46% of the initial value . The BOD5/COD ratio increased from 0.01 to 0.14 . To obtain detailed information on the reaction processes during ozonation and the resulting oxidation products organic and inorganic anions were analyzed . Oxidation and cleavage of the azo group yielded nitrate . Cleavage of the sulfonic acid groups of aromatic rings caused an increase in the amount of sulfate . Formic acid and oxalic acid were identified as main oxidation products by high performance ion chromatography (HPIC) . The concentrations of these major products were monitored at defined time intervals during ozonation.

Water Res, 2002 Apr, 36(7), 1887 - 95
Grey-box modelling of aeration tank settling; Bechman H et al.; A model of the concentrations of suspended solids (SS) in the aeration tanks and in the effluent from these during Aeration tank settling (ATS) operation is established . The model is based on simple SS mass balances, a model of the sludge settling and a simple model of how the SS concentration in the effluent from the aeration tanks depends on the actual concentrations in the tanks and the sludge blanket depth . The model is formulated in continuous time by means of stochastic differential equations with discrete-time observations . The parameters of the model are estimated using a maximum likelihood method from data from an alternating BioDenipho waste water treatment plant (WWTP) . The model is an important tool for analyzing ATS operation and for selecting the appropriate control actions during ATS, as the model can be used to predict the SS amounts in the aeration tanks as well as in the effluent from the aeration tanks.

Water Res, 2002 Apr, 36(7), 1715 - 24
Effect of water purification on its radioactive content; Jimenez A et al.; We have analyzed the dissolved activity of various radionuclides of natural origin (226Ra and (234,235,235)U) and artificial origins (90Sr and (239+240)Pu), together with other non-radioactive physico-chemical parameters (pH, conductivity, dry residue, {Ca2+}, {Mg2+}, {K+} and {Fe(2+,3+)}, in both pre-potable and potable water from 17 treatment plants in Extremadura (Spain) . We have established a series of criteria and complementary techniques to the traditional methods of purification, aimed at the quantitative elimination of the presence in solution of the mentioned radionuclides . We highlight: (a) the increment of the mineral content of the water in its treatment succeeds in eliminating 226Ra, until reaching values close to 70%; (b) the increment of the mineralization of the water by addition of chemical reagents, conducted within the pH values 7.1 and 7.8, succeeds in eliminating up to 90% of the total uranium in dissolution; (c) the elimination of 90Sr during the purification is poor, in general, reaching average levels of only 15% when the purification process is practiced within concrete ranges for potable water (pH > 7, conductivity > 150 microS/cm, dry residue > 150 mg/l, {Ca2+} > 10 mg/l and {Mg2+} > 1.2 mg/l), and finally, (d) the decrease of the solubility of the iron, as low as it can get during the purification process, together with an increase of the conductivity associated, in principle, to parallel increments of other variables not analyzed in this work, such as SO4(2-), CO3(2-), etc., the activity of dissolved (239+240)Pu decreases to 90% . The application of the traditional processes of water purification outside the ranges and criteria formulated can increase the presence in dissolution up to 400%, for some radionuclides, largely the consequence of its redissolution from the non-soluble fraction of the water.

J Photochem Photobiol B, 2002 Jun, 67(2), 71 - 108
Reaction pathways and mechanisms of photodegradation of pesticides; Burrows HD et al.; The photodegradation of pesticides is reviewed, with particular reference to the studies that describe the mechanisms of the processes involved, the nature of reactive intermediates and final products . Potential use of photochemical processes in advanced oxidation methods for water treatment is also discussed . Processes considered include direct photolysis leading to homolysis or heterolysis of the pesticide, photosensitized photodegradation by singlet oxygen and a variety of metal complexes, photolysis in heterogeneous media and degradation by reaction with intermediates generated by photolytic or radiolytic means.

Environ Sci Technol, 2002 May 1, 36(9), 2054 - 9
Simultaneous determination of fuel oxygenates and BTEX using direct aqueous injection gas chromatography mass spectrometry (DAI-GC/MS); Zwank L et al.; A direct aqueous injection-gas chromatography/mass spectrometry (DAI-GC/MS) method for trace analysis of gasoline components in water is presented . The method allows for the simultaneous quantification of the following solutes: methyl tert-butyl ether (MTBE), its major degradation products (tert-butyl formate, tert-butyl alcohol (TBA), methyl acetate, and acetone), and possible substitutes of MTBE as an octane enhancer in gasoline (tert-amyl methyl ether, ethyl tert-butyl ether) as well as benzene, toluene, ethylbenzene, p-xylene, m-xylene, and o-xylene (BTEX) . No enrichment or pretreatment steps are required, and sample volumes of only 50 microL are needed for analysis . The detection limits in two different matrixes (spiked lake water and contaminated groundwater) are < or = 2 microg/L for most analytes and < 0.2 microg/L for MTBE, benzene, and toluene . The accuracy of the DAI-GC/MS method was excellent as determined from comparison with headspace-GC/MS and purge-and-trap-GC/MS . The DAI-GC/MS method has been applied to various environmental studies, which demonstrated its versatility . The applications comprised both laboratory (MTBE degradation in water treatment, quantification of polar gasoline components) and field (MTBE degradation ata gasoline spill site) investigations.

Emerg Infect Dis, 2002 Jun, 8(6), 619 - 24
Cryptosporidium oocysts in a water supply associated with a cryptosporidiosis outbreak; Howe AD et al.; An outbreak of cryptosporidiosis occurred in and around Clitheroe, Lancashire, in northwest England, during March 2000 . Fifty-eight cases of diarrhea with Cryptosporidium identified in stool specimens were reported . Cryptosporidium oocysts were identified in samples from the water treatment works as well as domestic taps . Descriptive epidemiology suggested that drinking unboiled tap water in a single water zone was the common factor linking cases . Environmental investigation suggested that contamination with animal feces was the likely source of the outbreak . This outbreak was unusual in that hydrodynamic modeling was used to give a good estimate of the peak oocyst count at the time of the contamination incident . The oocysts’ persistence in the water distribution system after switching to another water source was also unusual . This persistence may have been due to oocysts being entrapped within biofilm . Despite the continued presence of oocysts, epidemiologic evidence suggested that no one became ill after the water source was changed.

J Air Waste Manag Assoc, 2002 May, 52(5), 563 - 72
Evaluation of the RAMS continuous monitor for determination of PM2.5 mass including semi-volatile material in Philadelphia, PA; Pang Y et al.; The real-time ambient mass sampler (RAMS) is a continuous monitor based on particle concentrator, denuder, drier, and tapered element oscillating microbalance (TEOM) monitor technology . It is designed to measure PM2.5 mass, including the semi-volatile species NH4NO3 and semi-volatile organic material, but not to measure PM2.5 water content . The performance of the RAMS in an urban environment with high humidity was evaluated during the July 1999 NARSTO-Northeast Oxidant and Particles Study (NEOPS) intensive study at the Baxter water treatment plant in Philadelphia, PA . The results obtained with the RAMS were compared to mass measurements made with a TEOM monitor and to constructed mass obtained with a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS) sampler designed to determine the chemical composition of fine particles, including the semi-volatile species . An average of 28% of the fine particulate material present during the study was semi-volatile organic material lost from a filter during particle collection, and 1% was NH4NO3 that was also lost from the particles during sampling . The remaining mass was dominantly nonvolatile (NH4)2SO4 (31%) and organic material (37%), with minor amounts of soot, crustal material, and nonvolatile NH4NO3 . Comparison of the RAMS and PC-BOSS results indicated that the RAMS correctly monitored for fine particulate mass, including the semivolatile material . In contrast, the heated filter of the TEOM monitor did not measure the semi-volatile material . The comparison of the RAMS and PC-BOSS data had a precision of +/-4.1 microg/m3 (+/-9.6%) . The precision of the RAMS data was limited by the uncertainty in the blank correction for the reversible adsorption of water by the charcoal-impregnated cellulose sorbent filter of the RAMS monitor . The precision of the measurement of fine particulate components by the PC-BOSS was +/-6-8%.

Risk Anal, 2002 Apr, 22(2), 235 - 43
Physical injury risks associated with drinking water arsenic treatment; Frost FJ et al.; We estimated the number of transportation deaths that would be associated with water treatment in Albuquerque to meet the EPA’s recently proposed revisions of the Maximum Contaminant Level (MCL) for arsenic . Vehicle mileage was estimated for ion exchange, activated alumina, and iron coagulation/microfiltration water treatment processes to meet an MCL of 0.020 mg/L, 0.010 mg/L, 0.005 mg/L, and 0.003 mg/L . Local crash, injury, and death rates per million vehicle miles were used to estimate the number of injuries and deaths . Depending on the water treatment options chosen, we estimate that meeting an arsenic MCL of 0.005 mg/L will result in 143 to 237 crashes, 58 to 98 injuries, and 0.6 to 2.6 deaths in Albuquerque over a 70-year period, resulting in 26 to 113 years of life lost . The anticipated health benefits for Albuquerque residents from a 0.005 mg/L arsenic MCL, estimated using either a multistage Weibull or Poisson model, ranged from 3 to 80 arsenic-related bladder and lung cancer deaths prevented over a 70-year period, adding between 43 and 1,123 years of life . Whether a revised arsenic MCL increases or reduces overall loss of life in Albuquerque depends on the accuracy of EPA’s cancer risk assessment . If the multistage Weibull model accurately estimates the benefits, the years of life added is comparable or lower than the anticipated years lost due to transportation associated with the delivery of chemicals, disposal of treatment waste, and operation of the water treatment system . Coagulation/microfiltration treatment will result in substantially fewer transportation deaths than either ion exchange or activated alumina.

Waste Manag, 2002, 22(2), 209 - 13
The Bacillus subtilis rec-assay: a powerful tool for the detection of genotoxic substances in the water environment . Prospect for assessing potential impact of pollutants from stabilized wastes; Takigami H et al.; The Bacillus subtilis rec-assay has been specially developed to detect genotoxicity in environmental water samples . The rationale of the B . subtilis rec-assay is based on the relative difference of survival of a DNA repair-recombination proficient strain and its deficient strain, which is interpreted as genotoxicity . This assay method can be very powerful in that it has higher sensitivity for the detection of mutagens in highly polluted waters than other bacterial mutation assays . Hydrophobic fractions from various environmental waters were fractionated by using XAD-2 resins and assayed, targeting the detection of organic genotoxic substances . Genotoxic response was detected in most of them, which revealed that many unknown micropollutants with genotoxicity occur in public water bodies . Positive response was also detected from a treated municipal solid waste (MSW) landfill leachate . Genotoxicity remaining in the treated effluent suggests that genotoxic micropollutants may pass through conventional water treatment processes such as activated sludge treatment process . Without proper control of waste quality and landfill facilities, waste landfill could be a heavy pollution source.

Environ Technol, 2002 Mar, 23(3), 345 - 51
The use of waterworks sludge for the treatment of dye wastes; Basibuyuk M et al.; Water treatment works using coagulation/flocculation in the process stream will generate a waste sludge . The works in Adana, Turkey uses ferric chloride . The potential for using this sludge for the treatment of reactive, direct, disperse, acidic, and basic dyestuffs by coagulation and sorption has been investigated . The sludge acted as a coagulant and removed colour with excellent removal efficiencies being obtained for basic, disperse and direct dyes . The optimum conditions were a pH value of 5 and a sludge dose of 2000 mg l(-1) . Mediocre results were obtained for acidic and reactive dyes . The efficiency of the sludge was also compared with alum and ferric chloride for the same group of dyes . The sludge was also used as a coagulant to treat the wastewater from a textile factory . At doses of 2000-4000 mg l(-1), the sludge was as effective as ferric chloride and alum at removing COD . Sorption tests showed that the disperse and reactive dyes did not bind to the sludge . Langmuir and Freundlich constants were determined for the other three types of dye . Rate constants for the adsorption were determined using the Lagergren equation.

Water Res, 2002 Mar, 36(6), 1640 - 8
The effect of drinking water treatment on the spatial heterogeneity of micro-organisms: implications for assessment of treatment efficiency and health risk; Gale P et al.; The effect of drinking water treatment (ferric coagulation, floc blanket clarification, rapid sand filtration) on the spatial heterogeneity of five species of micro-organism was studied at pilot scale . It was found that the spatial heterogeneity of vegetative bacteria (namely total coliform and heterotrophic (22 degrees C; 3 d) bacteria) was little affected by treatment . Indeed, counts of total coliform bacteria within 500 l volumes of treated water were Poisson distributed (i.e . showed minimum variation) . In contrast, treatment appeared to increase the spatial heterogeneity (or clustering) of both aerobic spores indigenous to the raw water and Bacillus subtilis var niger spores added to the raw water . Furthermore, B . subtilis var niger spores added to the raw water were detected in the treated water 25 h after termination of spiking to the raw water . The effect on C . parvum oocysts added to the raw water could not be determined because few oocysts broke through treatment into the treated water . Indeed oocyst removals of 5-6 logs were apparent . “Species-specific” differences in the removal ratios were also demonstrated . It is concluded that audits for treatment processes based on single 100 ml “spot” samples for spores will tend to over-estimate the net spore removal and hence underestimate the public health risk . Spatial heterogeneity of counts in treated water contributes to explaining why no “ideal” surrogate has been identified for treatment plant performance.

Water Res, 2002 Mar, 36(6), 1629 - 39
Disinfection of Bacillus subtilis spores with chlorine dioxide: a bench-scale and pilot-scale study; Radziminski C et al.; Chlorine dioxide (ClO2) inactivation of Bacillus subtilis ATCC 19659 spores was examined at pilot-scale during periods representative of winter and summer temperature extremes at the Britannia Water Treatment Plant in Ottawa, Canada . In addition, bench-scale experiments using the same source water (Ottawa River, Ontario, Canada), as well as buffered and unbuffered laboratory waters were conducted using B . subtilis spores . Bench-scale inactivation of B . subtilis spores by ClO2 was similar to reported values for Cryptosporidium parvum (both organisms being more resistant to ClO2 than Giardia lamblia), suggesting the possibility that these spores may be used as potential indicators for protozoan parasites . Additionally, spore inactivation was observed to be influenced by pH in laboratory (distilled deionised water) water but not in Ottawa River water . At pilot-scale, spore inactivation was influenced by water temperature: a ClO2 dose of 2.5 mg/L resulted in a spore inactivation of approximately 2.0 log10 and 0.5 log10 at water temperatures of 23.2d egrees C and 5.2 degrees C, respectively . Chlorite concentrations remained below both the US EPA maximum contaminant level of 1.0 mg/L and the maximum contaminant level goal of 0.8 mg/L for up to 2.0log10 B . subtilis inactivation.

Water Sci Technol, 2002, 45(4-5), 167 - 74
Sensor system using polarization analysis method to monitor oil-on-water in water purification plants and rivers; Sanuki Y et al.; Some 80% of accidental pollution in river water is caused by oil spills . Oil spills can cause serious damage such as suspension of water intake at water purification plants and major harm to ecosystems in the lower reaches of rivers . This is because oil-on-water tends to spread easily, quickly exacerbating the damage . To address this problem, an automated, continuous sensor system with high sensitivity can be used for early detection of spill accidents . We have developed a sensor system for detecting oil-on-water based on a polarization analysis method . Its advantages include: a) no direct contact with sample water; b) minimal maintenance; c) largely unaffected by foreign matter and waves on the water surface; and d) much higher sensitivity than simple visual observation . This paper describes the measurement principle and configuration of the sensor system, and discusses the results of sensitivity tests and tests on the influence of water turbidity, foreign matter and waves . We will also consider some of the limitations of the new system.

What do Bioengineers do?

Bioengineers deal with a wide variety of problems. Students with bioengineering degrees may work as biomedical engineers with medical practicioners to develop new medical techniques, medical devices, and instrumentation for manufacturing companies. Clinical engineers work in hospitals and clinics to maintain and improve the vast amount of technological support required in modern medicine. With advanced degrees in the various fields of bioengineering, some graduates perform basic research related to biology and medicine in the research laboratories of educational and governmental institutions or in the medical industries.

Bioengineering is the application of engineering techniques and understanding to medical or biological systems. Traditionally medical research has been performed by medical doctors. It was found, however, that sometimes Doctors ended up re-inventing or re-discovering things that had already been understood or discovered in the physical sciences because the Doctors were unaware of what had been studied in those sciences. Similarly when engineers turned their attention to medical problems they often found that the problems that were interesting from a physical science perspective were unimportant from a medical perspective.

Recently, therefore, there has been a huge increase in collaboration between Medical Doctors and Engineers. Examples of problems that have benefited from this type of collaboration are the development of artificial organs, laser and radiation treatments for cancer, and improved imaging technology such as the MRI.

Collaboration has also begun to occur more often between engineers and people in other biological sciences such as marine biology. In these areas, once again, engineering techniques are being applied to biological systems to provide increased insight and better models of the biological world. At UMass Dartmouth one such collaboration is the modeling of plankton transport in turbulent ocean flow.

Mechanical engineering plays a large role in bioengineering because biological systems quite often involve fluid flow, such as blood flow, ocean currents and wind, as well as heat effects, transport of chemicals and mechanical stresses. These days almost every mechanical engineering department has at least some faculty working in the area of bioengineering.

Aquaculture (sometimes misspelled “aquiculture”) is the cultivation of aquatic organisms, such as fish, shellfish, algae and other aquatic plants. Mariculture is specifically marine aquaculture, and thus is a subset of aquaculture. Some examples of aquaculture include raising catfish and tilapia in freshwater ponds, growing cultured pearls, and farming salmon in net-pens set out in a bay.

Aquaculture has been one of the fastest growing segments of global food production in recent decades, and has been hailed as an answer to declining wild fish stocks caused largely by overfishing.

Tuna farming in Australia, as well as of other species, has had immense success.

In some limited or specialized locations, United States, Hawaii aquaculture embraces a wide range of experimentation NELHA with applications for various combinations of DOW Deep Ocean Water, SOW Surface Ocean Water & renewable energy sources Gateway with commercially available electricity and fresh water.

Challenges In countries like the U.K., Canada, Norway, and Chile, salmon and trout farming are one of the fastest-growing forms of agriculture. Salmon farming, like other food producing operations such as beef, wheat or tomatoes can impact the environment. In particular organic wastes from fish cages can have a significant effect on water quality and the population structure of organisms, increasing the occurance of toxic algal blooms, as has been the case in Scotland, but even a month of fallow time can return the area to pristine condition.

Like other agriculture production, it must stand up to a rigourous evaluation of any environmental impact. Salmon aquaculture has come under increasing scrutiny from environmental nongovernmental organizations (ENGO’s). In Canada, salmon farming sites occupy a small portion of the coastal zone areas where they are located. The total area occupied by Canadian salmon farms in British Columbia and the Bay of Fundy in New Brunswick is about 8,900 acreas which is less than 0.01% of the coastal area where these sites are located.

Bioengineering involves the study of the human body from the engineering perspective. It is an emerging field which combines several disciples including mechanical, chemical, and electrical engineering with human and animal physiology to develop engineering solutions to the body. In college, students will take engineering courses along with biology and anatomy courses to learn about the human body. Bioengineering may be offered with a pre-med program. If you are interested in both engineering and medicine, this field should be considered. Examples of bioengineering applications in medicine include the pacemaker for heart patients, articifial limbs and joints. Bioengineering concentrates on combining biological science and engineering to study, define and utilize the interaction of these disciplines to solve engineering problems. It focuses on the utilization of plants and animals for the benefit of humans and to maintain a healthy environment. a, f. Students in the area need a strong background in biology, particularly at the cellular and organism level, chemistry, fluids, processing, thermodynamics, and physiology. Bioengineering is the use of engineering principles of analysis and design to solve problems in medicine and biology.

Wild Pacific and Atlantic salmon stocks have seen significant declines over the last several decades, before salmon farming operations started. These declines were caused by a combination of factors including climate change, overfishing and freshwater habitat destruction. Canadian salmon farmers have significantly reduced the escape of their salmon. The evidence shows that the escape of farmed salmon on Canada’s west coast poses low risk to Pacific salmon, however concerns have been raised on the East coast that wild Atlantic salmon may interbreed with salmon that escape from farms.

Many farmed fish species are carnivorous, meaning that other wild fish species must be harvested to maintain the fish farm, but these are species which are not used for human consumption. A large portion of the fish meal used in fish feeds comes from the trimmings and discards of commercial species. More and more feeds are made using poultry and vegetable oils as substitutes for fish oil.

Other problems with aquaculture include the potential for increasing the spread of unwanted invasive species, as farmed species are often not native to the area in which they are farmed. When these species escape, they can compete with native species and damage ecosystems. Another problem is the spread of introduced parasites, pests, and diseases.

Mariculture is the cultivation of marine organisms for food, either in their “natural environment” or in seawater in ponds or raceways. An example of the latter is the farming of marine fish, prawns, or oysters in salt water ponds. By definition, mariculture is a specialized branch of aquaculture.

The Japanese have developed a clever process for free ranching marine fishes. The principle is based on behavioral conditioning and the migratory nature of certain species of marine fishes. The fishermen first raise fish hatchlings in a closely knitted net in a harbor. They sound a underwater honk before each feeding. When the young fishes are old enough, the fishes are freed from the net. The fishes grow up in the open sea. During spawning season, these fishes return to their birthplace. The fishermen harvest the fishes by sounding the honk and then raise the net.

Mariculture is not limited to food production only, products such as cultured pearls are considered mariculture as well.

Off the coast of California, the top few feet of natural kelp beds are harvested by boats with mowers. Kelp provides alginin, an edible material used in ice cream and cosmetics.

A biosensor is a device for the detection of an analyte that combines a biological component with a physicochemical detector component.

It consists of 3 parts:

the sensitive biological element (biological material (eg. tissue, microorganisms, organelles, cell receptors, enzymes, antibodies, nucleic acids etc), a biologically derived material or biomimic) The sensitive elements can be created by biological engineering. the transducer in between (associates both components) the detector element (works in a physicochemical way; optical, electrochemical, thermometric, piezoelectric or magnetic.) Arrays of many different detector molecules have been applied in so called electronic nose devices, where the pattern of responce from the detectors is used to fingerprint a substance.

A canary in a cage, as used by miners to warn of gas could be considered a biosensor. Many of todays biosensor applications are similar, in that they use organisms which respond to toxins at a much lower level than us to warn us of their presence. Such devices can be used both in environmental monitoring and in water treatment facilities.

A bio-based material is simply an engineering material made from substances derived from living tissues. These materials are sometimes referred to as biomaterials, but this word also has another meaning.

Strictly the definition could include many common materials such as wood and leather, but it typically refers to modern materials that have undergone more extensive processing.

Milk is an excellent food source for humans and bacteria alike. It is full of vitamins, fats, minerals, nutrients and carbohydrates. It is rich in the protein casein which gives milk its characteristic white color. The most abundant carbohydrate is the disaccharide lactose, “milk sugar.” At room temperature, milk undergoes natural souring caused by lactic acid produced from fermentation of lactose by fermentative lactic acid bacteria. This accumulation of acid (H+ ions) decreases the pH of the milk and cause the casein to coagulate and curdle into curds and whey. Curds are large, white clumps of casein and other proteins. Whey is the yellow liquid that is left behind after the casein has formed curds. Thus, bacteria obtain nutrients from the milk, inadvertently curdle it and humans use it as the first step in making many dairy products. The microbes important for dairy product manufacturing can be divided into two groups, primary and secondary microflora. Products undergoing fermentation by only primary microflora are called unripened and those processed by both primary and secondary microflora are called ripened. Primary microflora are fermentative lactic acid bacteria which cause the milk to curdle. e, j, c. During dairy product production, milk is first pasteurized to kill bacteria that cause unwanted spoilage of the milk and of the downstream milk products. Primary microflora consists of certain kinds of Lactococcus, Lactobacillus and Streptococcus that are intentionally added to pasteurized milk and grown at 30°C or 37°C (temperature depends on the bacteria added). Secondary microflora include several different types of bacteria (Leuconstoc, Lactobacillus, and Propionibacterium), yeasts and molds; they are only used for some types of surface ripened and mold ripened cheeses. The various combinations of microflora determine what milk product you will end up with.

Examples include:

polylactic acid - a polymer produced by fermentation bioplastics - including a soy oil based plastic now being used to make body panels for John Deere tractors corn starch based packing pellets Retrieved from “http://en.wikipedia.org/wiki/Bio-based_material”

In surgery, a biomaterial is a synthetic material used to replace part of a living system or to function in intimate contact with living tissue. Compare this definition to that of bio-based material.

The Clemson University Advisory Board for Biomaterials defined a biomaterial as “a systemically and pharmacologically inert substance designed for implantation within or in corporation with living systems”.

In 1986, the Consensus Conference of the European Society for Biomaterials defined a biomaterial as “a nonviable material used in a medical device, intended to interact with biological systems”.

Another definition of biomaterial is “any substance (other than drugs) or combination of substances synthetic or natural in origin, which can be used for any period of time, as a whole or as a part of a system which treats, augments, or replaces any tissue, organ, or function of the body”.

A biomaterial is different from a biological material such as bone that is produced by a biological system. Artificial hips, vascular stents, artificial pacemakers, and catheters are all made from different biomaterials.

Biomimetic materials are not made by living things but have similar compositions and properties to living things. The calcium hydroxyapatite coating found on many artificial hips is a sort of fake bone that allows for easier attachment of the implant to the living bone.

Surface functionalization may provide a way to transform a bio-inert material into a biomimetic or even bio-active material by coupling of protein layers to the surface. Different approaches to functionalization of biomaterials exist. Plasma processing has been successful applied on chemically inert materials like polymers or silicon to graft various functional groups to the surface.

Biopharmaceuticals are medical drugs (see pharmacology) produced by biotechnology. The first such substance approved for therapeutic use was recombinant insulin in 1982.

The life support system is a group of devices that allow a human being to survive in an environment hostile to human life, eg. outer space or underwater.

The life support system may supply:

Air Water Food It must also maintain the correct body temperature, an acceptable pressure on the body and deal with the body’s waste products. Shielding against harmful external influences auch as radiation and micro-meteorites may also be necessary.

In biology and physics, animal locomotion is the study of how animals move, and is part of biophysics.

Much of the study is an application of Newton’s third law of motion: if at rest, to move forwards an animal must push something backwards. Terrestrial animals must push the solid ground, swimming and flying animals must push against a fluid (either air or water). The topic splits into five disjoint categories:

animal locomotion on land (walking and running) animal locomotion in air (flying) animal locomotion in water (swimming including fish and ducks) animal locomotion on the surface layer (small animals relying on surface tension such as the water strider) animal locomotion by water-walkers (the basilisk lizard). The distinction between the second and third topics is that in the second, the animal does not need to expend energy to defeat gravity; in or on the water, buoyancy counteracts the animal’s weight.

A biosphere is that part of a planet’s terrestrial system— including air, land and water— in which life develops, and which life processes in turn transform. It is the collective creation of a variety of organisms and species which form the diversity of the ecosystem. From the broadest geophysiological point of view, the biosphere is the global ecological system integrating all living beings and their relationships, with their interaction with the elements of the lithosphere (rocks), the hydrosphere (water), and the atmosphere (air). Individual life sciences and earth sciences may use biosphere in more limited senses (see below).

Different unripened milk products are created by using various starting products and bacteria. For buttermilk production, Lactobacillus bulgaris (named for its country of discovery, Bulgaria) is added to skim milk to curdle it. Leuconostoc is then added to thicken it. Sour cream is made the same way except cream is used instead of skim milk. During yogurt production, dry milk protein is added to milk to concentrate the milk before addition of actively growing Streptococci and Lactobacilli. Butter is produced by curdling and slight souring from Streptococci growing in sweet cream. Leuconostoc is then added so it can synthesize diacetyl, a compound that gives butter its characteristic aroma and taste. The milk is then churned to aggregate the fat globules into solid butter. Thus milk type and bacteria will determine the dairy product produced. j, k, b, f, g. Cheese is an important product of fermentative lactic acid bacteria. Particularly in the past, cheese was valued for its long shelf life. Due to its reduced water content, and acidic pH, bacterial growth is severely inhibited. This causes cheese to spoil much more slowly than other milk products. Consequently, the art of cheese production has spread throughout Europe, each country manufacturing many different types of cheeses. Cheese production has three steps: curd formation, curd treatment and curd ripening.

The term was coined by the geologist Eduard Suess in 1875. The concept of biosphere is thus from geological origin and is an indication of the impact of Darwin on Earth sciences. The ecological concept of the biosphere comes from the 1920s (see Vladimir I. Vernadsky), preceding the 1935 introduction of the term ecosystem by Arthur Transley. The biosphere is an important concept in astronomy, geophysics, meteorology, biogeography, evolution, geology, geochemistry, and generally speaking all life and earth sciences.

Biosphere is often used with more restricted meanings. For example, geochemists also give define the biosphere as being the total sum of living organisms (usually named biomass or biota by biologists and ecologists). In this sense, the biosphere is one of the four components of the geochemical model, the others being the lithosphere, hydrosphere, and atmosphere).

Some consider that the semantic and conceptual confusion surrounding the term biosphere is reflected in the current debates related to biodiversity, or sustainable development. The meaning used by geochemists is one of the consequences of the specialization of modern science.

Many appear to prefer the word ecosphere, coined in the 1960s-’70s. Others, however, claim this word is sullied by association with the idea of ecological crisis.

Vernadsky defined ecology (originally intended as the “economy of nature”) as the science of the biosphere.

The Second International Conference on Closed Life Systems defined biospherics as the science and technology of analogs and models of Earth’s biosphere, ie. artificial Earth-like biospheres. Some also include the creation of artificial non-Earth biospheres–for example, human-centered biospheres or a native Martian biosphere—in the field of biospherics.

Biosphere 1, Biosphere 2, Biosphere 3 When the word Biosphere is followed by a number, it is usually referring to a specific biosystem.

Biosphere 1 - The planet Earth. Biosphere 2 - A laboratory in Arizona which contains 3.15 acres (13,000 m²) of closed ecosystem. Biosphere 3 - Experiment conducted by Russians in 1967-8. [1] (http://www.permanent.com/s-bios3.htm)[2] (http://www.biospherics.org/russia.html)[3] (http://www.biospheres.com/hisbios3fax.html) See also: biome, cryosphere, Biosphere Reserve, noosphere, geosphere, eco-evolution, homeostasis, life support system

Earth’s Biosphere Earth is the only place where life is proven to exist. The planet’s lifeforms are sometimes said to form a “biosphere”. This biosphere is generally believed to have evolved ~3.5B years ago. The biosphere is divided into a number of biomes, inhabited by broadly similar flora and fauna.

On land, biomes are separated primarily by latitude. Terrestrial biomes lying within the Arctic and Antarctic Circles are relatively barren of plant and animal life, while most of the more populus biomes lie near the Equator.

Terrestrial organisms in temperate and arctic biomes have relatively small amounts of total biomass, smaller energy budgets, and display prominent adaptations to cold, including world-spanning migrations, social adaptations, homeothermy, estivation and multiple layers of insulation.

Some theorists therefore believe that the Earth is poorly suited to life. However, every part of the planet supports life, from the polar ice caps to the Equator. Recent advances in microbiology have proven that microscopic life lives inside rocks under the Earth’s surface, and that the total mass of microbial life in so-called “uninhabitable zones” may, in terms of sheer biomass, outweigh all animal and plant life combined on the surface of the Earth.

Oceans mediate the cold and distribute nutrients. The Antarctic krill, Euphausia superba, for example, is generally considered to be the most successful animal of the planet, with a biomass probably over 500 million tonnes (c.f. human biomass of about 250 million tonnes).

Biosphere 2 is a manmade closed ecological system in Oracle, Arizona built by Edward P. Bass, Space Biosphere Ventures and others. It was used to test if and how people could live and study in a closed biosphere, while carrying out scientific experiments. It explored the possible use of closed biospheres in space colonization, and also allowed the study and manipulation of a biosphere without harming Earth’s. The name comes from the idea that it is modelled on “Biosphere 1″ - Earth.

project conducted two sealed missions; the first from 1991 September 26 to 1993 September 26, and the second for six months in 1994. During the first mission, oxygen and carbon dioxide fell. Oxygen and other supplies were provided, and the project lost some credibility.

Columbia University In 1995 the Biosphere 2 owners transferred management to Columbia University. Since 1996, over 1200 graduate students have spent a year in the Biosphere 2 Center (as of 2003). The site has its own hotel and conference center. Columbia has since divested itself of all Biosphere-related responsibilities.

Science and engineering The scientific method is difficult to apply due to the complexity of the biosphere and the absence of a control. Like Project Apollo, Biosphere 2 is an achievement of engineering rather than science. The above-ground physical structure of Biosphere 2 was made of steel tubing and high-performance glass and steel frames. The frame and glazing materials were designed and made to specification by a firm run by a one-time student of Buckminster Fuller, Peter Pearce (Peter Pearce & Associates).

Difficulty of creating successful artificial biospheres

An interesting consequence of the experiment is that it showed the difficulty of copying the functions of the natural capital of the evolved Earth biosphere with infrastructural capital constructed by humans with present technology. Despite expenditure of over $150 million, this attempt at a new biosphere did not sustain eight humans, for a limited time, while the original sustains billions of humans, and shows little sign of failing any time soon.

Value of Earth’s biosphere Some economists have used the price of the Biosphere 2 project as an input to value of life calculations, and attempts to calculate the total value of all natural capital on Earth (see also: value of Earth). According to them: given that it does at least as good a job at sustaining humans as Biosphere 2, it should be worth at least as much per resident. This leads to a rather large, but finite, price of Earth itself.

Development of Green Chemicals from Biobased Materials. Key issues have been addressed relative to fermentation and the elimination of salt by-products. Improved esterification (secondary purification) and products and processes are being developed. Collaborations with industry include a Cooperative Research and Development Agreement with an electrodialysis developer (in process), a license for polymer use, and a Work-for-Others contract with a major agriprocessor. The program collaborates with and funds other ES sections and Argonne’s Environmental Research Division, and coordinates with four other national laboratories.

Development of Remediation Technology. Physical, chemical, biological, and geological approaches are used to solve a number of in-situ, ex-situ, and pollution prevention problems. Among the many and diverse technologies being applied are sonication, electrokinetics, membrane separations (e.g., electrodialysis, reverse osmosis, pervaporation), chelation/immobilization, magnetic separation, phytoremediation, bioremediation, microbiology, thermal desorption, and foam applications.

Bioengineering is a method of restoring damaged terrestrial and aquatic ecosystems. It emphasizes the use of live plants as the basic building blocks that begin the restoration process, and then, continue, on their own, the healing process that leads to a stable, climax plant and animal community. In its most refined form, bioengineering uses the physical properties of plants, such as their sheer resistance, tensile strength, and flexibility, to construct stabilizing structures such as live slope fascines and hedge brush layers, to stabilize earth slumps and landslides; live woven willow fences and willow brush mattresses and hydraulic fascines to protect and revegetate damaged stream banks; live siltation baffles, to rebuild washed out stream banks and flood terraces.

Bioengineering developed historically as did the practices of medicine, engineering, and architecture, beginning as a number of discrete techniques developed to solve specific problems. Knowledge of these techniques was part of the body of folk wisdom accumulated in prehistoric times and passed orally from generation to generation. In the last two centuries, this knowledge was compiled and codified, and finally in fairly recent times, it has been taught formally and practiced as a profession.

The system of technologies which we today call bioengineering can be traced to the ancient peoples of Europe and Asia. Some of the early western visitors to China told of river banks and dikes stabilized with large baskets woven of willow hemp or bamboo, and filled with rocks. There are fifteenth century scrolls showing villagers planting willow sprigs in stream banks.

In Europe during the nineteen twenties and thirties German, Austrian and Italian engineers and foresters began studying the methods that villages, both in Europe and Asia had evolved to repair their own damaged landscapes, and they added a scientific component, doing extensive testing of the many properties of plants, their rooting capabilities, their soil tolerance, temperature range, altitude range, salinity tolerance, drought tolerance, rooting methods, seeding methods. They learned the tensile strength of willow roots to be twenty five hundred pounds per square inch and that of fir roots to be eighty five hundred pounds.

Stem cells have generated more excitement, scrutiny and controversy than any other area of recent scientific study. The first stem cells, which were discovered half a century ago, were isolated from blood. Now, scientists around the globe are researching various types of stem cells for their potential to regenerate lost tissue and revolutionize medicine. Embryonic stem (ES) cells are derived from the embryo when it exists as a blastocyst. They have the ability to develop into all the different cell types found in the body. Actually, when a sperm fertilizes an egg, the resulting single cell begins to divide and multiply at a rate much faster than that observed in somatic cells. Scientists refer to these cells as totipotent stem cells (Figure 1). These primordial embryonic cells have the potential to grow into a complete mammal. Within days of fertilization, these new and dividing cells form a hollow sphere, called a blastocyst. Stem cells arising in the inner mass of the blastocyst are called the ES cells. The ES cells are considered pluripotent - they can divide indefinitely and blossom into all the various tissue types of the human body, but they have the lost the totipotent ability to grow into a separate being. k, l, d, g, k. After roughly 14 days, ES cells divide to give rise to what will eventually develop into the spine. At this stage, the stem cells within the embryo are considered multipotent. These stem cells can grow into some tissues, but not all tissues. Those destined to become bone or blood, for example, may not be able to form stomach or skin.

They refined these ancient, labor intensive techniques, and applied them to modern ecological problems, discovering that this style of repair work becomes indistinguishable from the surrounding natural landscape in just a few short years.

What is Soil Bioengineering

Soil Bioengineering is an established method of stabilizing or protecting eroded soils. It is unique in that plants and plant parts (roots, stems) are used as the main structural components to reinforce the soil and to provide protection. Soil bioengineered structures rely on living or dead plant materials and can act as drains and prevent earth movement. The techniques outlined in this manual use woody plants that root from dormant cuttings. There are effective methods of using wetland or herbacious plants, coir logs, and pre-grown plant mats in soil bioengineering for lake shores and river banks. These methods are not listed in this manual because they can be more complex and costly, making them unsuitable for the active volunteer.

History of Soil Bioengineering

Soil bioengineering has been widely practiced in Europe, in various forms, since the 1500’s. Today there is a professional association dedicated to the promotion and advancement of soil bioengineering, called the Gesellschaft fur Ingenenieurbiologie. In North America, soil bioengineering was also in widespread use from the late 1920’s to the 1940’s. But with the availability of cheap energy and the high cost of labour in the 1950’s, steel and concrete structures became preferred over soil bioengineered structures.

Fortunately for rivers and streams in North America, soil bioengineering has been regaining popularity since the early 1980’s, and is now once again in widespread and successful use. Many large scale projects have been completed, such as the Rehabilitation of the Markham Branch of Highland Creek, and the Mad River Cribwall in Glen Huron.

Benefits of Soil Bioengineering.

There are many benefits associated with using soil bioengineered structures. The roots, stems and associated foliage from the cuttings used to build the structures form a protective vegetative cover that reinforces the soil and protects it from erosion. Because these structures are created with living vegetation, they grow stronger and more effective with age. This is in direct contrast to inert structures (gabions, concrete and sheet piling) which weaken and crumble with age. The root systems of the living structures penetrate the soil, providing substantial strength and resistance to movement. The roots of Heartleaf and Slender willow, as well as Carolina poplar, have grown deeply into a very compact soil. These growing plants will provide protection and stability long after the stakes, twine, and original cuttings in the fascine have decomposed.

Perhaps the greatest benefit of living structures lies in the many functions that they perform. Not only do they provide stability, but they provide food and cover for wildlife, oxygen and moisture through transpiration, and they are a part of the ecosystem. Living structures are also attractive and can be very cost effective. It is the habitat benefits of soil bioengineering that make the method interesting to those working to create habitat be it aquatic or terrestrial. Most of the techniques in this manual are built by hand, which makes them compatible with environmentally sensitive sites or sites with limited access.

Soil bioengineered structures also lend themselves to the volunteer group. They are relatively easy to build and with a bit of scrounging, the materials can be acquired for little cost.

Limitations of Soil Bioengineering

While soil bioengineering has many advantages, it does have limits. The use of soil bioengineered structures would be ineffective on a site that is densely shaded since the live materials used need sunlight in order to grow. Sites with toxic soils (or no soils !!) and extreme water velocities/level fluctuations should be avoided. The requirement of dormant materials also limits the use of soil bioengineering to seasons when access to certain sites may be limited. The most important thing to remember if you wish to use soil bioengineering is that you are building a LIVING structure, one that needs to grow.

The methods in this section of the Techniques chapter will provide most of the information you need to build the structures described. Those wishing to use soil bioengineering are also urged to refer to the authors listed in the bibliography.

Materials

Selection of species

Willows (shrubs and trees), dogwoods, and poplars are the main species that are readily available in Ontario. The species listed in Table X are described as either native, or non-native. Where possible, projects should avoid the use of non-native species since they can outcompete and displace native plants.

It is recommended that tree form willows be avoided when working on small streams. As the trees mature, the root systems will eventually fill in the floodplain, congesting the channel. This is particularly evident with Salix fragilis, and S. fragilis/alba. Shrub willows and dogwoods can provide the stability/habitat sought, while still allowing the stream to use its floodplain.

Poplars should not be used in stream projects where beaver dams are perceived as a problem. Beavers will cut and utilize a wide range of trees and shrubs, but they prefer poplars. Poplars are shade intolerant (will not grow in the shade), so they should be used in the open. They are a good species to use if quick growth is required. Beavers have also been known to browse on the live cuttings used in the construction of the various techniques. This browsing can be serious if it occurs immediately after installation, before the structure has a chance to grow. We recommend inspecting the structures periodically and repairing any damage. If the browsing continues to be a problem, removal of the beavers may be required. Once the structure is growing, the browsing rarely destroys the structure.

All of the species listed under Recommended Species section, possess a certain degree of environmental flexibility in terms of their ability to grow in a range of soil types and moisture regimes. To maximize your chances of success, you should try to select species whose growing conditions roughly match the environmental conditions of the project site. We also recommend mixing several species of cuttings in each structure. Each method lists some suggested species. Care should also be taken to select species with root systems that match the nature of the soil movement at the project site. Sites with deep earth movements may require plants with deep and widespread root systems.

By definition, stem cells have two important characteristics that distinguish them from other types of cells. First, they are unspecialized cells that renew themselves for long periods of time through cell division of at least one daughter cell. Secondly, under certain physiological or experimental conditions, they can be induced to differentiate. This means that they can divide into cells with special functions, such as the beating cells of the heart muscle or the insulin-producing cells of the pancreas. Discovery of ES Cells The work that laid the foundation for ES cell discovery was the study of teratocarcinomas, complex tumors containing a mix of specialized cell types as well as a population of unspecialized cells. These unspecialized cells are called embryonal carcinoma (EC) cells. The latter were shown to be pluripotent and could give rise to various cell types both in vitro and in vivo. It was therefore natural to consider using these cells for therapeutic purposes. b, g, k, c, j. However, EC cells never seemed ideal for this purpose because they had an abnormal number of chromosomes and originated from tumors. Careful study of the induction of teratocarcinomas in experimental animals, as well as an understanding of the biology of EC cells and early embryos, led scientists to the discovery of ES cells in the early 1980s. The demonstration that ES cells contained the normal number of chromosomes and were truly pluripotential has influenced many scientific disciplines.

Willows, dogwoods, and poplars are pioneering species. This means that they are often the first species to grow in an area that has been cleared or disturbed. This trait gives these woody plants the ability to grow quickly, vigorously and in abundance. Photo #4 shows a 2.5 year old Heartleaf willow live stake. This live stake, planted in a streambank, has grown substantially in a relatively short period of time. This abundant fast growth is a result of full sun exposure and proper soil conditions. In shaded conditions, most plant material will grow poorly and be relatively short lived. Over time, the species originally planted may give way to other types of trees and shrubs. .

Locating material donor sites

All of the species listed in this chapter can, with a bit of effort, be found in areas were they can be collected free of charge. Many of the materials listed in Table X cannot be purchased or are prohibitively expensive if available. The locating of donor sites is best done in advance of project construction. Most species are easiest to identify in the spring and summer, when catkins and leaves are present. Potential sites can be found by driving around, paying attention to roadside ditches, abandoned fields, hydro corridors (or other utility right of ways), drainage ditches, or riverbanks. For those that have access, airphotos can also be used to locate donor sites. In most cases donor sites will be privately owned so you will need to secure permission to harvest. Township or county road superintendents are constantly battling willows in their attempts to maintain drainage in roadside ditches. This is also true of Drainage Superintendents, who often welcome having “nuisance” willows removed from municipal drains.

In some cases there will be materials growing onsite. Ideally, donor sites should be close to the project site, as distant sites require more effort logistically to use.

When to Harvest

All live materials should be harvested when they are dormant. While many species of willow will root from a cutting that is not dormant, the chances of success are slim, and only if specific site conditions are met. Dormant materials have the highest probability of growing with the broadest range of site conditions. One of the best indicators of dormancy is when the leaves have turned color, and fall from the twig. The time in which this happens can vary, but as a general rule one should not harvest materials until:

October 20 - Southern Ontario October 15 - Central Ontario October 10 - Northern Ontario

Materials can be cut and used through the winter till spring, until the buds have begun to flush (break open, usually in early April). Materials should NOT be used once the buds have broken.

Extending the Working Season

Using dormant materials in the time that they are readily available restricts projects to a window of opportunity from Mid October to Mid April. One method of extending this season is to place dormant materials in cold storage. Willow and dogwood cuttings have been stored successfully for as long as 10 weeks after harvesting. Cuttings should be stored at temperatures between 3 - 5oC, with moderate to high humidity. Some molding of the cut ends will occur, but the stems should be fine as long as they don’t dry out. Commercial storage may be expensive, but options include ice rinks, vegetable barns (cabbage storage etc.) or refrigerated truck units.

How to Harvest

Materials can be cut with pruning shears, clearing saws, hand saws, or chain saws. Since many of the structures require substantial amounts of cuttings, a mechanical saw is the most efficient. For cuttings with diameters from 10 mm to 70 mm, a clearing saw is recommended. Since the cuts will be close to the ground, a clearing saw is far easier on the operator than a chainsaw. Chainsaws work best on materials over 70mm. Both chainsaws and clearing saws are potentially dangerous tools, those using them are urged to wear the appropriate safety equipment. When tying together materials for transport - construct the bundles so that all of the growing tips are aligned in the same direction. This makes it much easier to use the materials onsite. Bundles should be constructed such that they are easy to transport and should be tied so that they do not fall apart when handled. Leave all of the side branches intact. The use of a set of sawhorses makes it easier to tie the bundle. For this manual, a bundle is typically 40 cm in diameter.

When cutting the material be sure to make the cuts 15 - 30 cm above ground. This will ensure successful coppice growth from the stem. Caution - for safety reasons leaving high stumps should be avoided in areas frequented by people. This coppice growth can be cut 2 - 3 years later and is often easier to handle than the original stems, grows faster as a cutting, and the number of stems sometimes increases tenfold over a given area. A note of caution - for safety reasons, leaving high stumps should be avoided in areas frequented by people. To help you in the construction of future projects, keep track of areas that have been mowed for clearing, or harvested by previous soil bioengineering projects. They can be re-cut in the future, usually providing better quality material than during the first harvest.

Bioengineering is concerned with interdisciplinary involvement on the part of scientists and engineers, drawn from the physical, engineering, and life sciences to:

(a) study and quantify the mechanisms and phenomena connected with life sciences and medical sciences; and

(b) develop diagnostic and treatment procedures, surgical guidelines, and prosthetic and rehabilitative devices. Conversely, there are possibilities for bioengineers to identify solutions to engineering problems utilizing understanding gained from the study of living systems.

Bioengineering calls for individuals, competent in specific engineering and science disciplines, to communicate and collaborate effectively with individuals or groups in medical and life sciences. The results of a reasonable period of biomedical engineering endeavour will often see the emergence of a new technique or device to facilitate medical diagnosis or treatment.

Bio-engineering Techniques for Slope Stabilization and Control of Sediment Generation

Kay & Associates, International Training Consultants

1. Overview

Bio-engineering is the successful use of vegetation in concert with engineering structures to increase slope stability against shallow mass wasting.

Plant material increases soil strength through the transfer of root tensile strength to soil shear strength, buttressing and arching. Bio-engineering systems provide additional support beyond that which can be provided by single plants. As the plants mature they increase in strength and provide increased resistance to natural forces.

The following bio-engineering solutions uses native plant species to;

Enhance slope stability Control sediment generation. Maintain Plant and Wildlife Biodiversity. Stabilization of the surface layers of the slopes from wind, gravitational, and hydraulic forces is achieved with the benefit of energy dissipation of water and detritus moving down-slope. Infiltration of water increases the amount of water for plant establishment while vigorous plant growth dissipates excess slope water to the atmosphere. Entrapment of sediment is accomplished through filtering action of established vegetation and a developing duff layer.

Natural vegetation establishment is enhanced by providing suitable microsites for plants by;

Stabilization of surface soils. Increase in water infiltration. Formation of terraces with lower slope angles. Seeds from natural dispersal tend to remain in place and seedlings have a chance to develop in the stabilized surface areas. The temporary vegetation from the Bio-engineering treatments acts as pioneering species, allowing time for natural succession to form a more permanent vegetation cover.

2. Willow Whips and other plants that sprout from cuttings.

a) Harvesting

Willow whips are expected to be cut (make clean cuts with unsplit ends) locally by local labour in the dormant season. (from when the leaves start to turn yellow in the autumn until growth starts in the spring) These willow whips will be approximately 2 meters long and selectively harvested from convenient sites without damage or harm to the natural environment. The whips will be placed in bundles and wrapped in medium weight polyethelyne (leave ends open) and tied with cord. (the poly is to protect the stems during handling and to retain moisture, do not leave out in the sun. Place in the shade) These willow whips will be kept in cold storage until time for use. It may be advantageous to take the time at the harvesting stage to prepare the required lineal meters of wattle bundles. (see: contour-wattling for instructions in making the wattle bundles)

b) Handling

It is important to remember that in each cutting that you are handling a live plant. Handle gently, and don’t damage or bruise the stems.

In the harvesting and planting phases, do not let the cuttings dry out. Do not leave them out in the sun or spread out on a windy slope. (keep covered or in the shade)

Keep all planting stock moist, cool and covered when in storage, transport and on the jobsite when planting.

b) Pre-planting preparation

Soaking of the cuttings prior to planting has shown to be beneficial to survival rates. A period of 24 hrs to 72 hrs (one to three days) is recommended.

3. Planting of Cuttings

Different methods for planting of the willow whips may be utilized.

a) Live Staking (Upright Planting)

The Live Staking (upright planting) method is commonly employed on slopes requiring remediation work for slope stability and in conjunction with the methods described below.

Cutting

The willow whips are usually cut into 500mm lengths for planting vertically in the ground.

Spacing

Planting spacing on most slopes will be from 200mm to One meter apart. The worker will be instructed by the Bio-engineering supervisor in what to look for in ideal planting sites to get the best plant survival and growth.

Planting

The willow whip (if strong enough and the soil is loose) may be pushed or driven into the ground. Otherwise a suitably deep hole may be made in the ground using a metal bar or other suitable method (see tools). Approx. 2/3rd’s of the whip should be below ground and there should be two buds visible on the exposed 1/3rd above the ground. The cutting should make contact with the bottom of the hole (no air space). Compact the dirt around the stem.

Biological role and properties of stem cells Stem cells differ from other kinds of cells in the body. All stem cells, regardless of their source, have three general properties: they are capable of dividing and renewing themselves for long periods; they are unspecialized; they can choose to become one of the many different types of cells present in the body based on signals from their environments. Finding the answers to two fundamental questions about stem cells that relate to their long-term self-renewal is crucial to our ability to successfully grow these cells in laboratory and in turn use them for various tissue engineering and cellular therapies. The first question deals with why embryonic stem cells can proliferate for extended periods of time in the laboratory without adopting a specialized fate, while most adult stem cells cannot. The second issue addresses which factors in living organisms normally regulate stem cell self-renewal and differentiation. Discovering the answers to these questions may make it possible to understand how cell proliferation is regulated during normal embryonic development or during the abnormal cell division that ultimately leads to cancer. Biotechnologists uses techniques derived from a variety of disciplines. e, j, k, a, e Their main objectives are the innovation, development and optimal operation of processes in which biochemical catalysis plays a fundamental role. Biotechnology relies on each contributing discipline to better understand the technical language, potential and limitations of other areas.

(b) Contour-wattling

Contour-wattling for slope stabilization and also to provide sediment control in fine textured and sandy soils adjacent to watercourses

Contour-wattling is the placing of bundles of twigs in a prepared trench and burying them across the slope at regular contour intervals resulting a lightly terraced slope. All work starts at the base of the slope.

Wattles construction

Wattles are constructed by the laying of willow whips in alternate directions to form a bundle 200 to 300mm in diameter.

The bundles are compressed tightly and firmly tied with binder twine every 300 to 400mm. (do not allow bundles to dry out)

Trenching

An excavated trench (approx. ½ the depth of the bundle is excavated along the contour of the slope. Note: trenches must kept horizontal to prevent the mis-directing of surface water. (use an inclinometer) Trenching should not precede the placing of the wattles by more than 1hr to minimize the drying out of the soil.

Placing, Staking and Covering of the Wattles

The bundles of wattles are laid in the trench allowing the fringe ends to overlap.

Stakes (minimum 600mm length) are driven through the bundles (beside the tie string) approximately every 500mm. The purpose to the stakes is to retain the bundle in place (particularly from frost heaving) until the roots can take over.

The bundles are partially backfilled using native upslope material. The soil should be worked around and into the bundle itself. Workers should walk on the backfilled material and also on the bundles as much as possible to help work the soil into the bundles and to provide compaction of the backfill material. The excavated material from the next trench provides this backfill material. The backfilled portion must be outsloped as not to retain or pond water. A side portion of the bundle forming the terrace “wall” will always be left exposed for propagation. The finished slope will have a series of out-sloped terraces with the wattle bundles just poking out at the face of each terrace.

Alternate Wattling Method

In moist soils, the driving in of long (minimum 1meter) stakes (Steel or Wood) along the desired terrace line (150-200mm apart, depending on the size of the longitudinal whips used) with 150-200mm left exposed. Then long whips of Willow are placed against this “fence” and then backfilled with native material, creating a bench face with the exposed wattling. This procedure is continued up the slope.

c) Brush Layering (Horizontal Planting), Full Continuos Bench

Brush Layering (horizontal planting), Full bench is also used to reduce the amount of slope angle and provide continuos reinforced bench support.

Useful for slopes that are over-steepened that will benefit from reduced slope angle.

It is also beneficial if there is an opportunity for mechanical assistance of slope preparation. You may wish to consider the use of a small mini-excavator or a “spider” excavator. These smaller, lighter machines can be flown in by Helicopter to sites not accessible by road. The “Spider” excavator, waking on it’s four feet, also has the ability to traverse slopes of up to 100% to gain site access with surprisingly negligible ground disturbance.

Bench Construction.

A flat bench will be excavated with mechanical equipment or by hand work using mattock and shovel, at the base of the slope. This bench will be the full length of the slope and usually 1 to 2 meters in depth. The willow whips will be placed side by side (about 100mm apart) on this bench with the tops facing outward and with a 150mm overhang.

Slope material (native material, dirt, stones etc) will be excavated down from the slope on to the top of the previously prepared bench with its side by side placed willow whips. The depth (ranging from 200mm to 2meter) of this covering material (and the next bench) will vary with the slope angle and slope materials.

Length of Whips.

Whips will be 1 to 2 meters long and laid horizontally on the constructed bench and backfilled (covered over to a depth of 200mm to 2meters) in the terracing process. (There must be a minimum of 150mm of the willow whip freely protruding to establish new growth)

Size and spacing of Benches.

These benches, running the full length of the slope, consisting of one single layer of Willow whips are constructed to the top of the slope. The bench height will vary due to site conditions but is usually in a range of 200mm to 2 meters.

d) Brush Layering (Horizontal Planting), Random Bench

The Brush Layering (horizontal planting), Random Bench method is selectively employed in dry raveling sites to establish “islands” of vegetation and to ensure the planted stems maintain moisture in the dry period of the year and to provide protection from raveling material until the plant is established.

For slopes subject to raveling, a random spacing of short benches may be employed. The object is to create “islands” of Vegetation on the slope.

Length of Whips.

Whips will be 1 to 2 meters long and laid horizontally on a constructed bench and backfilled (covered over) in the terracing process. On some slopes, due to the nature of the ground material it will not be possible to use the full length of the willow whips.

Size and Spacing of Benches.

These benches, 1 to 2 meters in width, consisting of one single layer of Willow whips will be interspaced, in a staggered fashion, on the slope approximately every 3 to 4 meters in suitable random locations.

Bench Construction.

A flat bench will be excavated by hand with a mattock at the desired location on the slope. (The “Spider” excavator may be a useful tool on some slopes) This bench will be approximately 1 to 2 meters in width and 1 to 2 meters in depth. The willow whips will be placed side by side (about 100mm apart) on this bench with the tops facing outward.

Historically, biotechnology was an art rather than a science, exemplified in the manufacture of products like wine, beer and cheese. Manufacturing techniques were usually discovered by chance but then thoroughly and reproducibly worked out. However the molecular mechanisms were not understood. With major advances in biochemistry and microbiology, these processes have become better understood and improved. Modern biotechnological processes now include a wide range of new products including antibiotics, vaccines and antibodies and a variety of therapeutic proteins. Biotechnology has been further diversified by many new molecular innovations, allowing unprecedented changes to be made to living systems. Transgenic plants and animals are igniting a new era in agriculture and human gene therapy promises to eradicate many diseases which are currently incapacitating and untreatable. Environmentally, biotechnology is allowing major improvements in water and land management as well as bringing solutions to pollution generated by various industries. A key factor distinguishing a traditional biologist from a biotechnologist is the scale of operation. The biologist usually works in the range of nanograms to milligrams. Biotechnologists, depending on the project, may aim to generate quantities of desired product in kilograms or higher. As such, biotechnology aims to amplify biological processes. The developments in biotechnology are currently proceeding at a speed similar to that of microelectronics in the 1970s. Although the analogy is tempting, it is probably not realistic to expect that biotechnology will develop commercially at the same spectacular rate experienced by microelectronics. k, d, f, i, c. Nonetheless, biotechnology will still have a considerable impact across all industrial uses of the life sciences, in spite of the fact that some traditional means of production are still economically more favourable than the newer biotechnological methods. Chemical means of production that utilize petrochemical based feedstocks are still more economically sound compared to biotechnology driven routes for most industrial chemicals. Biotechnology will undoubtedly have great benefits in the long run in all sectors.

Native slope material (dirt, raveled stones etc) will be excavated down from the slope on top of the previously prepared bench and the side by side placed willow whips. The depth (approximately 200 to 500+mm) of this covering material will vary with the slope angle and slope materials. There must be a minimum of 150mm of the willow whip freely protruding to establish new growth.

(If fairly large boulders are readily available and can be moved by hand they can be placed on the bench created to assist in providing physical protection)

( 4 ) Live Pole Drains

Water piping or seeping out of a bank creates problems that can lead to slope instability. The use of a “Live Pole Drain” system can control and direct this potentially problem water.

Construction Starting at the water source location, excavate a small (2-300mm) trench to the desired discharge location. Take a pre-prepared bundle of Willow whips (3-400mm in Diameter) and place this bundle in the trench and then place others continuously end to end to the drain point. Backfill the trench, leaving just the top surface of the bundle of whips exposed. Ensure the discharge location is well armoured to receive the anticipated water flow.

This drainage system will convey a considerable amount of water with the added benefit of being a “living drain” with live willows growing out of it and dispersing water to the atmosphere. These drains can be used in many different ways. Eg. In a “Y” formation.

( 5 ) Sediment Control Tools

a) Wattlling for sediment control – If regular silt fence is left in place after a project work period it will require regular monitoring and eventual removal of the slit fence and also the removal of the collected silt.

As a practical alternative to regular silt fencing a unique sediment control barrier, is to construct a high wattle fence lined with silt fence or filter cloth. The area for trapped sediment would be planted with site-suitable species as Willows, Cottonwood, Cedar, and other wet-site shrubs and plants. It may be desirable to plant the sediment catchment area after the initial flush of sediment. It is recommended that the area be hand grass seeded (and fertilized) each growing season.

This sediment control device is now a permanent living structure that will trap sediment and not require the removal of that sediment.

b) Brush layering for sediment control – A sediment entrapment area can be created by slightly modifying the previously mentioned brush layering technique.

By constructing a shallow depression behind the brush layer, a sediment catchment area can be created. This area should also be planted etc. as in the above “Wattling for sediment control”

c) Monitoring – Regularly scheduled (and after peak storm events) monitoring a necessity just as it would be required for any control structure or moderate to high risk site.

( 6 ) Conifers and Hardwoods

Where they are native and suit the site, species such as Conifers and/or Hardwoods that can be planted as rooted stock may be a desirable addition to a bio-engineering stabilization project.

Larger species have the great ability to use water to dry the slope and their root systems will enhance the slope integrity and assist to achieve long term stability.

Consideration should be given to slope steepness and wind conditions and the mature size and height of the larger species.

Species selected should be native to the area, suited to the site conditions and suited to the site altitude.

( 7 ) Other Slope Stabilization Species

There may be other suitable shrub and tree species that are available near the remediation site that propagate from cuttings or that can be grown from seed and planted as rotted stock. Each region of the globe has it’s own native species that can be used as remediation tools. Observing similar sites nearby to the treatment area will give an indication of all the species of Trees, Shrubs, Plants and Grasses that you should be considering for your remediation work.

For example, in the American Pacific Northwest, Willow and Black Cottonwood will grow profusely from cuttings. In the same area, species that have performed well that are available in rooted stock are: Red Ozier Dogwood, Alder, Sumac among others.

Plants (ferns, wildflowers, vines, vetch and others) are also a viable tools for soil stabilization and sediment control. They can be transplanted directly from adjacent sites (may available from specialist nurseries) or be seeded.

It is essential to use care in non-native species selection. The introduction of a species that may be considered a nuisance(such as damaging to other native species), noxious(poisonous) or a weed must be avoided.

( 8 ) Grass seed and fertilizer.

Dry seeding Dry grass seed and fertilizer should be applied, using a broadcast spreader, the same day that the ground is disturbed, while the ground is friable (loose and open) to be most effective. This method can be used effectively even on quite steep slopes. However, after the ground has been armoured and compacted by sun and rain the seed and fertilizer has a tendency to roll down the slope and for the wind to blow the seed away.

The use of dry seeding in friable ground can be very cost effective and with good results. By the seed being retained (trapped) in the ground the seeding can be effectively done even when dry conditions can be expected after seeding as the seed remains in place until moisture conditions are right for seed propagation.

Hydro-seeding Hydro-seeding - Is the application of seed using a water slurry(containing the seed and fertilizer) combined with a mulch agent(to retain moisture and also physical protection from rain damage) and a tackifier(to make the mixture stick). There are many combinations of mix and a variety of specific materials and agents to use in site-specific locations.

Bonded fibre matrix – Is a product (containing seed, fertilizer, mulch and a specialized bonding agent) that is applied (using hydro-seeding equipment) as a solid blanket over the soil. This can give immediate weather protection from soil erosion for up to two years when it is expected that emergent vegetation will have matured.

Many new biotechnology companies have spun off from universities (for a few examples of companies in Vancouver see here). These companies are often technologically driven and multidisciplinary in nature. Product development can involve molecular biologists, clinical researchers, bioprocess engineers and sales staff. The business climate of biotechnology companies is often characterized by rapid change and considerable risk as one biotechnology innovation may quickly supercede another. Another peculiar feature of new biotechnology companies is that their business growth is often highly dependent on venture capital, as they require exceptionally high level of funding before profit sales return. Biotechnology & Chemical Engineering Many biotechnological processes may be considered as having a three-component central core, in which one part is concerned with obtaining the best biological catalyst for a specific function or process, the second part creates (by means of technical operation) the best possible environment for the catalyst to perform, and the third part (downstream processing) is concerned with the separation and purification of an essential product or products from a fermentation process. Biotechnology and the Environment Biotechnology has been successfully employed to reduce or eliminate various forms of air and water pollutants.

Methods developed by environmental biotechnologists might use the microorganisms to either break down or sequester pollutants. The concept of using microorganisms to treat pollution problems is not a new idea; microbes were first used as early as 1930s to treat industrial wastewaters. More recently they helped in the cleanup of oil spilled from the Exxon Valdez tanker off the coast of Alaska in 1989 as well as decontaminated water aquifers contaminated with various industrial chemicals such as phenol, trichloroethylene (TCE) and compounds present in various petroleum fractions. Opportunities for using microorganisms for bioremediation of soils contaminated with various industrial pollutants arose when scientists discovered that there is practically nothing that is not viewed as food by one microbe or another. Just as some insects can feed on leaves that are toxic to others, so some microbes can thrive on molecules that would poison most organisms. h, i, l, i, f. Microbes exist in nature that feed on toxic materials such as methylene chloride, detergents, phenol, sulfur and polychlorinated biphenyls (PCBs). Microbes metabolize the toxic compounds to produce harmless end products such as carbon dioxide, water and salt. The chemical conversions usually involve breaking large molecules into several smaller molecules, much as we break down the complex carbohydrates in our food to simple sugars such as glucose. In some cases, the by-products of a bacterial banquet are not simply harmless but actually useful. Methane, for example, can be derived from a form of bacteria that degrades sulfite liquor, a waste product of paper manufacturing. Methane can then be used in a wide range of industrial applications such as electricity production.

It is recommended that you consult an expert in hydro-seeding to get;

site specific products, value of product, controlled application, a successful “take” (growing grass) Timing of the application will need to be considered (Eg. weather seasons)

Seed mixture and fertilizer Always, a custom grass seed mixture, specific for the site and the season of application is strongly recommended, along with a recommended fertilizer mix, specific to the site soils. (you may need soil tests) There will also need to be specified application rates for both the seed and fertilizer. (The grass seed supplier may be able to assist and may have local knowledge of the area)

Native species The addition of native species to the seed mix is gaining strong acceptance. There is an increasing availability of native species from the seed suppliers. Also shrub and tree seed may be considered to add to the mixture. Eg. In the American Pacific Northwest, Alder should be considered if the work commences after natural Alder seeding for the year has taken place.

Ensuring seeding project quality In any seed application it is essential to ensure that specified application rates are being actually applied and specified products are being used.

The only sure way to confirm is to place random test cards(150mm square and for dry seeding, coated with a sticky substance) on the site prior to seeding and then sent to a laboratory for a painstaking seed count.

For realistic on-site supervision you may;

Monitor the quantities (and types) of materials brought on site and calculate the ratio of the application area to product and compare to specifications. Closely inspect the ground for consistent application rates. Conduct your own seed estimation using the seeds of visible size and the fertilizer pellets in random locations as a guide. (a rough rule of thumb for dry seeding (average) applications is two large seeds and two fertilizer pellets(on the average) in a square inch. Ensure that the seed has been transported and stored correctly and the seed is not water damaged or contaminated by another spilled product. Eg. Petroleum products or other harmful agents. Caution: The specifications for the area to be treated if taken directly from a map or aerial photo will not equal the actual ground distances on a slope and will lead to a shortage of materials for the actual ground area required to be treated.

( 9 ) Project Timing

Harvesting of cuttings (Willow Whips) will ideally take place in the dormant season. (no leaves on the stem) However successes have been obtained with cuttings taken at all times of the year.

Soaking of the cuttings a minimum of 24 hrs prior to planting has shown to have effectively increased survival rate.

Bio-engineering field work will take place after any work of buttressing for slope stability in the immediate area is completed. (The machine construction of reinforcing walls at the base of the slopes. Eg. Such as the placing of large boulders to a wall height of 2meters or engineered structures)

Ideally, the bio-engineering field work should commence in the spring. Consideration will want to be given to such limiting factors as;

The ground is clear of snow and thawed. Heavy and/or extended period of rains are over. Waiting until extreme dry conditions are past. That the work be completed before the next expected extreme weather event. (extreme wet, dry, hot or cold) Planting (live staking and grass hydro-seeding) should be limited to seasons in which adequate moisture is expected to be available for propagation.

( 10 ) Existing Vegetation

The existing natural vegetation should not to be destroyed or damaged in the processes of completing the prescription. Where there is existing vegetation, it is expected that (where practical) it will be incorporated into the remedial work plan.

( 11 ) Naturally re-vegetating species

It is expected that wind born and animal transported seeds from adjacent vegetation (including fruit bearing shrubs) will establish themselves in the stabilized soil with the assistance of the emerging vegetation.

( 12 ) Maintenance

Scheduled on-going Inspection and Monitoring is required to;

Re-install areas that have failed to grow. Repair failed areas. Correct nutrient deficiencies (fertilize). ( 13 ) Biodiversity

A well rounded prescription addresses the key elements to maintain plant bio-diversity and wildlife concerns.

Integrated Laboratory of Bioengineering

PRESENTATION

The Integrated Laboratory of Bioengineering (L.I.B.) was inaugurated in July 1989 and started to work effectively in January 1990. Since then, the human team responsable for research has been incorporated and it has been given the essential infrastructure to undertake its working activities, the own ones or the ones subjected to agreements and collaboration contracts with external public and private organizations.

The L.I.B. is organized in two areas: Bioelectronic Area, directed by Doctor Mr. J.M. Ferrero Corral, Professor of Electronic Technology of the U.P.V., who also directs it as a whole, and Biochemistry Area, directed by Mr. Angel Montoya Baides, Doctor in Biochemistry and Professor in the U.P.V.. The activities developed are:

Biomedical Instrumentation Line. The staff of the Bioelectronic Area, who also belongs to the Electronic Engineering Department, is in charge of it. This Line was started more than twelve years ago by Doctor Ferrero in the DIE and was later incorporated to the L.I.B. Its wide experience is guaranteed by the successful execution of I+D numerous projects, financed by private companies and public institutions.

Line of Modeling of Bioelectrical Systems. The Bioelectronic Area is in charge of it. It started its activities at the beginning of 1993 and is nowadays focused in the development of heart cellular or complete models. They collaborate with the Johns Hopkins University (Baltimore, MD, U.S.A.) for the study of the influence of various parameters upon propagation of the action potentials in the myocardium.

Line of Research Biosensors, in which Bioelectronic and Biochemistry investigators participate. This Line, which has performings already working at an industrial level and various projects in a developing phase, gives sence to the Integrated Laboratory as a multiple discipline team. The integration of the Bioelectronic and Biochemistry Areas in a unique laboratory with the aim of developing Biosensors, is at an international level almost the only example at this field, and guarantees the fast exchange of information and technology between both Areas, essential in the development of Biosensors.

Production of Monoclonel Antibodies, for the specific necessities of the L.I.B. in the Biosensors Line, and also to give service to external institutions. This activity is developed by the Biochemistry Area staff, and it has already originated numerous collaborations with other research teams at a national and international level.

The Colorado Alliance for Bioengineering (CAB) is a consortium of local universities committed to producing a high quality workforce and enhancing bioengineering research and development in the state of Colorado. Biomedical engineering is the scientific discipline that applies engineering sciences solutions to life science questions. The promise of biomedical engineering research and its practical applications are to improve and extend the lives of persons throughout the world. CAB has its origins in meeting the need to encourage additional research and education in bioengineering combined with facilitating the complex task of developing devices, information programs and systems usable by health related organizations. CAB goals are:

For Research – Establish world-class stature and global leadership For Industry – Facilitate and provide innovations for the bioengineering and life sciences industries For Education – Facilitate and support the establishment of multi-institutional inter-disciplinary bioengineering education programs, lectures and seminars.

what is bioengineering? Bioengineering integrates physical, chemical, or mathematical sciences and engineering principles for the study of biology, medicine, behavior, or health. It advances fundamental concepts, creates knowledge for the molecular to the organ systems levels, and develops innovative biologics, materials, processes, implants, devices, and informatics approaches for the prevention, diagnosis, and treatment of disease, for patient rehabilitation, and for improving health.

Food spoilage has been an important problem throughout human history. Finding ways to overcome this problem was crucial as communities became larger and individuals no longer grew their own food. Some kind of system was needed to maintain the nutrient content of various food stuffs for long periods of time and prevent them from rotting and becoming inedible. Early solutions to food spoilage Food spoilage is caused by the growth of microorganisms, primarily bacteria and fungi, that convert nutrients into energy which they use for their own growth. Depletion of the nutrient content of food as well as the secretion of byproducts from this biochemical process are two things which contribute to the spoilage of food rendering it inedible. Since ancient times, humans have used many methods to extend the shelf life of food although not always understanding how these processes worked. Salting and drying are two very simple techniques that prevent rotting; both make the food an inhospitable environment for microorganisms. Canning is another technique first developed in the late 18th century by Nicholas Appert, a French confectioner, who, after 15 years of research, realized that if food is sufficiently heated and then sealed in an air tight container it will not spoil. Here the heating of food, kills all residual microorganisms present in the food and immediate sealing prevents the reentry of other contaminanting organisms. Napoleon immediately put this discovery to work in his armed forces and awarded Appert a prize of 12,000 francs for his discovery. Later, an Englishman, Peter Durand, took the process one step further and developed a method of sealing food into unbreakable tin containers. This was perfected by Bryan Dorkin and John Hall, who set up the first commercial canning factory in England in 1813. In 1859, Louis Pasteur definitively showed that microorganisms were responsible for food spoilage for the first time. This discovery led to the coining of the term “pasteurization” to describe the process where liquids with the potential to spoil (milk in particular) are heated for preservation.

Fermentation In some cases, the growth of microorganisms in food can be put to good use for the production and preservation of various types of food. Fermentation is arguably the earliest example of biotechnology and refers to the metabolic process by which microbes produce energy in the absence of oxygen and other terminal electron acceptors in the electron transport chain such as fumarate or nitrate. In ancient times, it was considered as a way to both preserve food and to retain nutritional value. It was probably accidentally discovered in ancient Egypt when dough, made from ground up wheat and rye, was left for a period of time before cooking. In contrast to dough that was immediately cooked, it was observed that the aged dough expanded in size and when cooked produced tastier, lighter bread. The process was not completely reproducible: sometimes the uncooked dough yielded good bread and other times it did not. However if small amounts of good dough was added to the next batch, the bread was again tasty. The Romans went onto improve and perfect this process and popularized this sort of bread throughout the European continent. The discovery of fermentation in Egypt also led to the first production of wine and alcohol. All these discoveries were largely phenomenological and it would be another 3000 years before the exact cause of fermentation was uncovered. It was Louis Pasteur, again, in 1857 who was able to demonstrate that alcohol can be produced by yeast when grown in particular conditions. This discovery revolutionized the modern food industry: for the first time the agent of fermentation was identified and could be used commercially.

Biotechnol Prog, 2003 Jul-Aug, 19(4), 1183 - 9
Experimental and theoretical analysis of tubular membrane aeration for Mammalian cell bioreactors; Qi HN et al.; A combination of experimental and theoretical approaches was used to characterize the dynamics of oxygen transfer in a membrane-aerated bioreactor . Pressure profiles along the length of the membrane at varying entrance and exit pressures were determined by actual experimental measurements, unlike most previous studies that have relied solely on theoretical descriptions of the pressure profile in the tubing . The mass transfer coefficient, k(L)a, was also determined under these conditions and was found to be essentially independent of tubing exit pressure . Measurement of the tubing pressure profile coupled with estimation of k(L)a allowed for computation of the oxygen transfer rate (OTR) along the length of the tubing . A mathematical model that incorporated friction pressure loss and losses due to tubing bending was developed to describe the pressure and hence OTR characteristics of membrane-aerated systems . The applicability of the model was verified by testing it on experimentally measured pressure data, and in all cases the model accurately described experimental data . When tubing properties are known, the mathematical model presented in this study allows for a priori estimation of OTR profiles along the length of the tubing . This information is vital for optimal design and scale-up of membrane-aerated bioreactors for mammalian cell culture.

J Pediatr Surg, 2003 Aug, 38(8), 1188 - 93
Fetal tissue engineering: chest wall reconstruction; Fuchs JR et al.; BACKGROUND/PURPOSE: This study was aimed at applying fetal tissue engineering to chest wall reconstruction . METHODS: Fetal lambs underwent harvest of elastic and hyaline cartilage specimens . Once expanded in vitro, fetal chondrocytes were seeded onto synthetic scaffolds, which then were placed in a bioreactor . After birth, fetal cartilage constructs (n = 10) were implanted in autologous fashion into the ribs of all lambs (n = 6) along with identical, but acellular scaffolds, as controls (n = 6) . Engineered and acellular specimens were harvested for analysis at 4 to 12 weeks postimplantation . Standard histology and matrix-specific staining were performed both before implantation and after harvest on all constructs . RESULTS: Regardless of the source of chondrocytes, all fetal constructs resembled hyaline cartilage, both grossly and histologically, in vitro . In vivo, engineered implants retained hyaline characteristics for up to 10 weeks after implantation but remodeled into fibrocartilage by 12 weeks postoperatively . Mononuclear inflammatory infiltrates surrounding residual PGA/PLLA polymer fibers were noted in all specimens but most prominently in the acellular controls . CONCLUSIONS: Engineered fetal cartilage can provide structural replacement for at least up to 10 weeks after autologous, postnatal implantation in the chest wall . Fetal tissue engineering may prove useful for the treatment of severe congenital chest wall defects at birth.

J Biotechnol, 2003 Aug 15, 103(3), 237 - 48
Integration of distributed multi-analyzer monitoring and control in bioprocessing based on a real-time expert system; Cimander C et al.; A computer system solution for integration of a distributed bioreactor monitoring and control instrumentation on the laboratory scale is described . Bioreactors equipped with on-line analyzers for mass spectrometry, near-infrared spectroscopy, electrochemical probes and multi-array gas sensors and their respective software were networked through a real-time expert systems platform . The system allowed data transmission of more than 1800 different signals from the instrumentation, including signals from gas sensors, electrodes, spectrometer detectors, balances, flowmeters, etc., and were used for processing and carrying out a number of computational tasks such as partial least-square regression, principal component analysis, artificial neural network modelling, heuristic decision-making and adaptive control . The system was demonstrated on different cultivations/fermentations which illustrated sensor fusion control, multivariate statistical process monitoring, adaptive glucose control and adaptive multivariate control . The performance of these examples showed high operational stability and reliable function and meet typical requirements for production safety and quality.

Biochem Biophys Res Commun, 2003 Aug 15, 308(1), 94 - 100
Large-scale purification of an antibody directed against hepatitis B surface antigen from transgenic tobacco plants; Valdes R et al.; The application of bioengineering to plants for production of biological products for human and animal use has expanded in recent years . The reasons for this expansion are several and include advances in the technology for novel production systems and the need for very large quantities of therapeutic proteins . The process of growing pharmaceutical proteins in plants, extracting, and purifying is a hard task considering the lack of available information concerning these topics . In this work, a recombinant murine monoclonal antibody specific for the hepatitis B surface antigen, expressed in stably transformed transgenic Nicotiana tabacum plants, was purified by means of a recombinant protein A Streamline chromatography as the main purification step . The antibody expression level varied with the age of the plants and the number of harvests from 40 to 15microg/ml and the maximum process yield was about 25mg of plantibody/kg of biomass . Protein A Streamline chromatography was successfully used in the purification process yielding a recovery of about 60% and a plantibody SDS-PAGE purity of over 90% but unexpectedly, previous clarification steps could not be totally avoided . The amino acid sequence recognized by this affinity purified plantibody was similar to its murine counterpart verifying the potentiality of plants to replace animals or bioreactors for large-scale production of this monoclonal antibody.

Biochem Biophys Res Commun, 2003 Aug 15, 308(1), 58 - 63
Development of transgenic fish for ornamental and bioreactor by strong expression of fluorescent proteins in the skeletal muscle; Gong Z et al.; In the present study, new applications of the transgenic technology in developing novel varieties of ornamental fish and bioreactor fish were explored in a model fish, the zebrafish (Danio rerio) . Three “living color” fluorescent proteins, green fluorescent protein (GFP), yellow fluorescent protein (YFP), and red fluorescent protein (RFP or dsRed), were expressed under a strong muscle-specific mylz2 promoter in stable lines of transgenic zebrafish . These transgenic zebrafish display vivid fluorescent colors (green, red, yellow, or orange) visible to unaided eyes under both daylight and ultraviolet light in the dark . The level of foreign protein expression is estimated between 3% and 17% of total muscle proteins, equivalent to 4.8-27.2mg/g wet muscle tissue . Thus, the fish muscle may be explored as another useful bioreactor system for production of recombinant proteins . In spite of the high level of foreign protein expression, the expression of endogenous mylz2 mRNAs was not negatively affected . Furthermore, compared to the wild-type fish, these fluorescent transgenic fish have no advantage in survival and reproduction.

Biotechnol Lett, 2003 Jun, 25(12), 987 - 92
Stereoselective reduction of 2-substituted cyclohexanones by Saccharomyces cerevisiae; Zarevucka M et al.; A comparative study of two modifications of enzymic reduction of ethyl N-{2-{4-{(2-oxo-cyclohexyl)methyl}phenoxy}ethyl}carbamate (1), an insect juvenile hormone bioanalog, was performed using Saccharomyces cerevisiae in two bioreactors of different size, 250-ml shake-flask and 1-l fermenter . The two major products of this reduction were obtained in 45-49% (w/w) yields but with > 99% enantiomeric purity . Their absolute configurations were assigned as ethyl (1S,2S)-N-{2-{4-{(2-hydroxycyclohexyl)methyl}phenoxy}ethyl}carbamate (2a) and ethyl (1R,2S)-N-{2-{4-{(2-hydroxycyclohexyl)methyl}phenoxy}ethyl}carbamate (3a).

Biotechnol Lett, 2003 Jun, 25(12), 927 - 33
Biodegradation of nonylphenol in a continuous packed-bed bioreactor; Soares A et al.; A packed bed bioreactor, with 170 ml glass bead carriers and 130 ml medium, was tested for the removal of the endocrine disrupter, nonylphenol, with a Sphingomonas sp . The bioreactor was first continuously fed with medium saturated with nonylphenol in an attempt to simulate groundwater pollution . At best, nonylphenol was degraded by 99.5% at a feeding rate of 69 ml h(-1) and a removal rate of 4.3 mg nonylphenol day(-1), resulting in a 7.5-fold decrease in effluent toxicity according to the Microtox . The bioreactor was then fed with soil leachates at 69 ml h(-1) from artificially contaminated soil (1 g nonylphenol kg(-1) soil) and a real contaminated soil (0.19 g nonylphenol kg(-1) soil) . Nonylphenol was always completely removed from the leachates of the two soils . It was removed by 99% from the artificial soil but only 62% from real contaminated soil after 18 and 20 d of treatment, respectively, showing limitation due to nonylphenol adsorption.

Biotechnol Lett, 2003 Jun, 25(11), 853 - 7
Estimation of Chinese hamster ovary cell density in packed-bed bioreactor by lactate production rate; Sun XM et al.; A method is described for estimating recombinant Chinese hamster ovary (rCHO) cell density in a packed-bed bioreactor by lactate production rate . The lactate production rate, which depended on both the cell numbers and cell growth rate, was modeled by segregating the cell population into two parts: one growing at a maximum specific growth rate and another non-growing . The individual cell in each part had the same lactate production rate . The established rate equation of lactate production matched the experimental data reasonably well and could be used to estimate the cell growth in the batch culture with microcarriers . Furthermore, in the perfusion culture of rCHO cells in a packed-bed bioreactor, the final cell density, 1.3 x 10(10) cells l(-1), estimated by lactate production rate, was comparable to the direct sample counting of 1.2 x 10(10) cells l(-1), showing that lactate production rate method would be useful in tracing the cell growth in packed-bed bioreactors.

Biodegradation, 2003 Jun, 14(3), 229 - 40
Use of sulfate reducing cell suspension bioreactors for the treatment of SO2 rich flue gases; Lens PN et al.; This paper describes a novel bioscrubber concept for biological flue gas desulfurization, based on the recycling of a cell suspension of sulfite/sulfate reducing bacteria between a scrubber and a sulfite/sulfate reducing hydrogen fed bioreactor . Hydrogen metabolism in sulfite/sulfate reducing cell suspensions was investigated using batch activity tests and by operating a completely stirred tank reactor (CSTR) . The maximum specific hydrogenotrophic sulfite/sulfate reduction rate increased with 10% and 300%, respectively, by crushing granular inoculum sludge and by cultivation of this sludge as cell suspension in a CSTR . Operation of a sulfite fed CSTR (hydraulic retention time 4 days; pH 7.0; sulfite loading rate 0.5-1.5 g SO3(2-) l(-1) d(-1)) with hydrogen as electron donor showed that high (up to 1.6 g l(-1)) H2S concentrations can be obtained within 10 days of operation . H2S inhibition, however, limited the sulfite reducing capacity of the CSTR . Methane production by the cell suspension disappeared within 20 days reactor operation . The outcompetition of methanogens in excess of H2 can be attributed to CO2 limitation and/or to sulfite or sulfide toxicity . The use of cell suspensions opens perspectives for monolith or packed bed reactor configurations, which have a much lower pressure drop compared to air lift reactors, to supply H2 to sulfite/sulfate reducing bioreactors.

Biotechnol Bioeng, 2003 Sep 20, 83(6), 735 - 42
A novel method of simulating oxygen mass transfer in two-phase partitioning bioreactors; Nielsen DR et al.; An empirical correlation, based on conventional forms, has been developed to represent the oxygen mass transfer coefficient as a function of operating conditions and organic fraction in two-phase, aqueous-organic dispersions . Such dispersions are characteristic of two-phase partitioning bioreactors, which have found increasing application for the biodegradation of toxic substrates . In this work, a critical distinction is made between the oxygen mass transfer coefficient, k(L)a, and the oxygen mass transfer rate . With an increasing organic fraction, the mass transfer coefficient decreases, whereas the oxygen transfer rate is predicted to increase to an optimal value . Use of the correlation assumes that the two-phase dispersion behaves as a single homogeneous phase with physical properties equivalent to the weighted volume-averaged values of the phases . The addition of a second, immiscible liquid phase with a high solubility of oxygen to an aqueous medium increases the oxygen solubility of the system . It is the increase in oxygen solubility that provides the potential for oxygen mass transfer rate enhancement . For the case studied in which n-hexadecane is selected as the second liquid phase, additions of up to 33% organic volume lead to significant increases in oxygen mass transfer rate, with an optimal increase of 58.5% predicted using a 27% organic phase volume . For this system, the predicted oxygen mass transfer enhancements due to organic-phase addition are found to be insensitive to the other operating variables, suggesting that organic-phase addition is always a viable option for oxygen mass transfer rate enhancement . 

Biotechnol Bioeng, 2003 Sep 20, 83(6), 681 - 6
Scalable inoculation strategies for microcarrier-based animal cell bioprocesses; Durrschmid M et al.; Scalability is a major demand for high-yield, stable bioprocess systems in animal cell culture-based biopharmaceutical production . Increased yields can be achieved through high-density cell culture, such as in the combination of microcarrier and fluidized bed bioreactor technology . To minimize inocula volume in industrial applications of fluidized bed fermentation systems, it is crucial to increase the bed volume in the reactor during the fermentation process . We tested scale-up strategy for the production of recombinant human arylsulfatase B (ASB) enzyme used in enzyme replacement therapy in patients afflicted with mucopolysaccharidosis type VI (MPS VI) . This enzyme was derived from Chinese hamster ovary (CHO) cells cultivated as adherent cell culture on Cytoline macroporous microcarriers (Amersham Biosciences, Uppsala, Sweden) using a Cytopilot Mini fluidized bed bioreactor (FBR; Amersham Biosciences, Vogelbusch, Austria) . Both 1:2 expansion (herein referred to as the addition of fresh, not-yet-colonized microcarriers) and 1:6 expansion of the carrier bed were performed successfully; the cells restarted to proliferate for colonizing these newly added carriers; and the stability of the culture was not negatively affected . 

Biotechnol Bioeng, 2003 Sep 20, 83(6), 653 - 67
Scale-up of Artemisia annua L . hairy root cultures produces complex patterns of terpenoid gene expression; Souret FF et al.; Hairy roots grow quickly, reach high densities, and can produce significant amounts of secondary metabolites, yet their scale-up to bioreactors remains challenging . Artemisia annua produces a rich array of terpenoids, including the sesquiterpene, artemisinin, and transformed roots of this species provide a good model for studying terpenoid production . These cultures were examined in shake flasks and compared with cultures grown in two types of bioreactors, a mist reactor and a bubble column reactor, which provide very different environments for the growing roots . Mist reactors have been shown previously to result in cultures that produce significantly more artemisinin per gram fresh weight of culture, while bubble column reactors have produced greater biomass . We have compared expression levels of four key terpenoid biosynthetic genes: 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), 1-deoxy-D-xylulose-5-phosphate synthase (DXS), 1-deoxy-D-xylulose-5-phosphate reductoisomerase (DXR), and farnesyl diphosphate synthase (FPS) in the three culture conditions . In shake flasks we found that although all four genes showed temporal regulation, only FPS expression correlated with artemisinin production . Light also affected the transcription of all four genes . Although expression in reactors was equivalent to or greater than that of roots grown in shake flasks, no correlation was found between expression level within six different zones of each reactor and their respective oxygen levels, light, and root-packing density . Surprisingly, transcriptional regulation of HMGR, DXS, DXR, and FPS was greatly affected by the position of the roots in each reactor . Thus, relying on a single reactor sample to characterize the gene activity in a whole reactor can be misleading, especially if the goal is to examine the difference between reactor types or operating parameters, steps essential in scaling up cultures for production . 

Biotechnol Lett, 2003 Feb, 25(3), 245 - 9
Biooxidation of ferrous iron by immobilized Acidithiobacillus ferrooxidans in poly(vinyl alcohol) cryogel carriers; Long ZE et al.; PVA-cryogels entrapping about 10(9) cells of Acidithiobacillus ferrooxidans per ml of gel were prepared by freezing-thawing procedure, and the biooxidation of Fe2+ by immobilized cells was investigated in a 0.365 l packed-bed bioreactor . Fe2+ oxidation fits a plug-flow reaction model well . A maximum oxidation rate of 3.1 g Fe2+ l(-1) h(-1) was achieved at the dilution rate of 0.4 h(-1) or higher, while no obvious precipitate was determined at this time . In addition, cell-immobilized PVA-cryogels packed in bioreactor maintained their oxidative ability for more than two months under non-sterile conditions.

Biotechnol Lett, 2003 Mar, 25(5), 417 - 20
A solid-state bioreactor coupled with forced aeration and pressure oscillation; Zhang X et al.; A novel design of a solid-state bioreactor, operated with periodic pressure oscillation coupled with forced aeration through the medium, gave efficient control of temperature . The evaluation of the bioreactor assembly with respect to temperature and cellulase production by Penicillium decumbens JUA 10 showed that, at 4 atm and the bed depth of 6 cm, the maximal temperature variation in the reactor was +1.5 degrees C at a set value of 30 degrees C compared with +6.8 degrees C in a static tray system . The highest cellulase and beta-glucosidase activities were 15 IU g(-1) and 51 IU g(-1) substrate dry matter at 96 h, respectively, while only 10 IU g(-1) and 24 IU g(-1) were obtained in the static tray culture system.

Biotechnol Lett, 2003 Jan, 25(1), 61 - 5
Biomass segregation in sage cell suspension culture; Bolta Z et al.; The biomass of sage (Salvia officinalis L.) cell suspension culture was composed of single cells and cell aggregates . The development of aggregated cell culture from a single-cell suspension was monitored by particle size distribution for four particle size classes . Particle size distribution was compared between the biomass grown in bioreactor and shake flasks . The size of the particles had a strong influence on content of secondary metabolite, ursolic acid (UA) . The single cell biomass fraction accumulated up to 7.7 mg UA g(-1) DW which was up to 50 times higher compared to aggregated biomass fractions.

Biotechnol Lett, 2003 Jan, 25(1), 39 - 45
Selective enrichment of Geobacter sulfurreducens from anaerobic granular sludge with quinones as terminal electron acceptors; Cervantes FJ et al.; A quinone-respiring, enrichment culture derived from methanogenic granular sludge was phylogenetically characterized by using a combined cloning-denaturing gradient gel electrophoresis (DGGE) method, which revealed that the consortium developed was dominated by a single microorganism: 97% related, in a sequence of 1520 base pairs, to Geobacter sulfurreducens . The enrichment culture could grow with acetate, formate or H2 when humic acids, the humic model compound, anthraquinone-2,6-disulfonate (AQDS), or chelated Fe(III) was provided as a terminal electron acceptor . The occurrence of a humic acid- or quinone-respiring microorganism in the microbial community of a wastewater treatment system suggests that this type of microorganisms may play a potential role in anaerobic bioreactors treating humus-containing wastewaters.

Biotechnol Lett, 2003 Jan, 25(2), 179 - 82
Suspension culture of hematopoietic stem cells in stirred bioreactors; Kwon J et al.; Hematopoietic stem cells have applications in bone marrow transplantations for the treatment of hematopoietic disorders . When murine hematopoietic stem cells were cultured in 50 ml stirred bioreactors for 14 d, stem-cell-antigen-1 positive cells (hematopoietic primitive progenitor cells) and long-term culture-initiating cells (hematopoietic stem cells) grew by 5-fold and 4-fold, respectively . These results show the possibility of growing hematopoietic stem cells using a stirred bioreactor.

Biotechnol Lett, 2003 Jan, 25(2), 133 - 8
H2 production with anaerobic sludge using activated-carbon supported packed-bed bioreactors; Lee KS et al.; Packed-bed bioreactors containing activated carbon as support carrier were used to produce H2 anaerobically from a sucrose-limiting medium while acclimated sewage sludge was used as the H2 producer . The effects of bed porosity (epsilon(b)) and substrate loading rate on H2 fermentation were examined using packed beds with epsilon(b) of 70-90% being operated at hydraulic retention times (HRT) of 0.5-4 h . Higher epsilon(b) and lower HRT favored H2 production . With 20 g COD l(-1) of sucrose in the feed, the optimal H2 production rate (7.4 l h(-1) l(-1)) was obtained when the bed with epsilon(b) = 90% was operated at HRT = 0.5 h . Flocculation of cells enhanced the retention of sludge for stable operations of the bioreactor at low HRTs . The gas products resulting from fermentative H2 production consisted of 30-40% H2 and 60-70% CO2 . Butyric acid was the primary soluble product, followed by propionic acid and valeric acid.

Biotechnol Lett, 2003 May, 25(10), 821 - 5
Induced reactive oxygen species improve enzyme production from Aspergillus niger cultivation; Sahoo S et al.; Intracellular reactive oxygen species (iROS) induction by HOCl was used as a novel strategy to improve enzyme productivities in Aspergillus niger growing in a bioreactor . With induced iROS, the specific intracellular activities of alpha-amylase, protease, catalase, and glucose oxidase were increased by about 170%, 250%, 320%, and 260%, respectively . The optimum specific iROS level for achieving maximum cell concentration and enzyme production was about 15 mmol g cell-1 . The type of iROS inducing the enzyme production was identified to be a derivative of the superoxide radical.

Expert Opin Biol Ther, 2003 Aug, 3(5), 705 - 13
Adipose tissue-derived therapeutics; Gimble JM; Human adipose tissue provides a uniquely abundant and accessible source of adult stem cells for applications in tissue engineering and regenerative medicine . The adult stem cells are isolated by collagenase digestion, differential centrifugation and subsequent adherence to a plasticware surface . Based on their immunophenotype, the cells are relatively homogeneous, with shared expression of integrin beta(1), the hyaluronate receptor, and the tetraspan protein CD9, among other markers . In response to chemical, hormonal or structural stimuli, the adipose-derived adult stem (ADAS) cells can differentiate along multiple lineage pathways, including adipocytes, chondrocytes, myocytes, neurons and osteoblasts . The cells can be transduced with viral vectors and have potential utility as gene delivery vehicles . Further studies will facilitate the clinical and commercial development of ADAS cells . First, it will be necessary to develop closed system bioreactors for the large-scale manufacture of ADAS cells . Second, methods that improve the vascularisation of in vivo implants will allow transplantation of larger engineered tissues . Finally, experiments must investigate the feasibility of transplanting allogeneic, as compared to autologous, ADAS cells for therapeutic applications . Based on the promising findings from adipose-derived and other adult stem cells to date, it is likely that future studies will address these challenges.

Heart Fail Rev, 2003 Jul, 8(3), 271 - 6
Cardiac tissue engineering, ex-vivo: design principles in biomaterials and bioreactors; Shachar M et al.; Cardiac tissue engineering has emerged as a promising approach to replace or support an infarcted cardiac tissue and thus may hold a great potential to treat and save the lives of patients with heart diseases . By its broad definition, tissue engineering involves the construction of tissue equivalents from donor cells seeded within 3-D biomaterials, then culturing and implanting the cell-seeded scaffolds to induce and direct the growth of new, healthy tissue . In this review, we present an up-to-date summary of the research in cardiac tissue engineering, with an emphasis on the design principles and selection criteria that have been used in two key technologies employed in tissue engineering, (1) biomaterials technology, for the creation of 3-D porous scaffolds which are used to support and guide the tissue formation from dissociated cells, and (2) bioreactor cultivation of the 3-D cell constructs during ex-vivo tissue engineering, which aims to duplicate the normal stresses and flows experienced by the tissues.

Rev Environ Contam Toxicol, 2003, 178, 93 - 164
Chromium-microorganism interactions in soils: remediation implications; Kamaludeen SP et al.; Discharge of Cr waste from many industrial applications such as leather tanning, textile production, electroplating, metallurgy, and petroleum refinery has led to large-scale contamination of land and water . Generally, Cr exists in two stable states: Cr(III) and Cr(VI) . Cr(III) is not very soluble and is immobilized by precipitation as hydroxides . Cr(VI) is toxic, soluble, and easily transported to water resources . Cr(VI) undergoes rapid reduction to Cr(III), in the presence of organic sources or other reducing compounds as electron donors, to become precipitated as hydroxides . Cr(VI)-reducing microorganisms are ubiquitous in soil and water . A wide range of microorganisms, including bacteria, yeasts; and algae, with exceptional ability to reduce Cr(VI) to Cr(III) anaerobically and/or aerobically, have been isolated from Cr-contaminated and noncontaminated soils and water . Bioremediation approaches using the Cr(VI)-reducing ability of introduced (in bioreactors) or indigenous (augmented by supplements with organic amendments) microorganisms has been more successful for remediation of Cr-contaminated water than soils . Apart from enzymatic reduction, nonenzymatic reduction of Cr(VI) can also be common and widespread in the environment . For instance, biotic-abiotic coupling reactions involving the microbially formed products, H2S (the end product of sulfate reduction), Fe(II) {formed by Fe(III) reduction}, and sulfite (formed during oxidation of elemental sulfur), can mediate the dissimilatory reduction of Cr(VI) . Despite the dominant occurrence of enzymatic and nonenzymatic reduction of Cr(VI), natural attenuation of Cr(VI) is not taking place at a long-term contaminated site in South Australia, even 225 years after the last disposal of tannery waste . Evidence suggests that excess moisture conditions leading to saturation or flooded conditions promote the complete removal of Cr(VI) in soil samples from this contaminated site; but Cr(VI) reappears, probably because of oxidation of the Cr(III) by Mn oxides, with a subsequent shift to drying conditions in the soil . In such environments with low natural attenuation capacity resulting from reversible oxidation of Cr(III), bioeremediation of Cr(VI) can be a challenging task.

Int J Artif Organs, 2003 Jun, 26(6), 507 - 13
Study of severe hepatitis treated with a hybrid artificial liver support system; Qian Y et al.; Artificial liver support system (ALSS) has been used to treat hepatic failure and has significantly decreased the mortality . TECA hybrid artificial liver support system (TECA-HALSS), which combines the hollow fiber bioreactor with a plasma exchange circuit, was used to assess the efficacy, safety and feasibility in treating severe hepatitis patients . The hybrid artificial liver support system (HALSS) consists of a bioreactor containing more than 5 x10(9) porcine hepatocytes and plasma exchange device . Fifteen patients with severe hepatitis were treated with this hybrid system . All patients experienced a reduction in symptoms such as fatigue, abdominal distention or ascites . After each treatment serum total bilirubin decreased markedly while prothrombin activity increased . There were ten patients whose progress of hepatocyte necrosis was stopped after HALSS treatment, and finally they recovered completely . One patient received liver transplantation after HALSS therapy and survived . No serious adverse events were noted in the fifteen patients.

Water Sci Technol, 2003, 47(10), 175 - 81
Automated sequencing batch bioreactor under extreme peaks of 4-chlorophenol; Bultron G et al.; The operation of a sequencing batch bioreactor is evaluated when high concentration peaks of a toxic compound (4-chlorophenol, 4CP) are introduced into the reactor . A control strategy based on the dissolved oxygen concentration, measured on line, is utilized . To detect the end of the reaction period, the automated system search for the moment when the dissolved oxygen has passed by a minimum, as a consequence of the metabolic activity of the microorganisms and right after to a maximum due to the saturation of the water (similar to the self-cycling fermentation, SCF, strategy) . The dissolved oxygen signal was sent to a personal computer via data acquisition and control using MATLAB and the SIMULINK package . The system operating under the automated strategy presented a stable operation when the acclimated microorganisms (to an initial concentration of 350 mg 4CP/L), were exposed to a punctual concentration peaks of 600 mg 4CP/L . The 4CP concentrations peaks superior or equals to 1,050 mg/L only disturbed the system from a short to a medium term (one month) . The 1,400 mg/L peak caused a shutdown in the metabolic activity of the microorganisms that led to the reactor failure . The biomass acclimated with the SCF strategy can partially support the variations of the toxic influent since, at the moment in which the influent become inhibitory, there is a failure of the system.

J Appl Microbiol, 2003, 95(2), 331 - 7
Xylitol production from high xylose concentration: evaluation of the fermentation in bioreactor under different stirring rates; Mussatto SI et al.; AIMS: To investigate the production of xylitol by the yeast Candida guilliermondii FTI 20037, in a bioreactor, from rice straw hemicellulosic hydrolysate with a high xylose concentration . METHODS AND RESULTS: Batch fermentation was carried out with rice straw hemicellulosic hydrolysate containing about 85 g xylose l(-1), in a stirred-tank bioreactor at 30 degrees C, under aeration of 1.3 vvm (volume of air per volume of medium per min) and different stirring rates (200, 300 and 500 rev min(-1)) . The bioconversion of xylose into xylitol by the yeast depended on the stirring rate, the maximum xylitol yield (YP/S = 0.84 g g(-1)) being achieved at 300 rev min-1, with no need to pretreat the hydrolysate for purification . CONCLUSIONS: To determine the most adequate oxygen transfer rate is fundamental to improving the xylose-to-xylitol bioconversion by C . guilliermondii . SIGNIFICANCE AND IMPACT OF THE STUDY: For the microbial production of xylitol to be economically viable, the initial concentration of xylose in the lignocellulosic hydrolysate should be as high as possible, as with high substrate concentrations it is possible to increase the final product concentration . Nevertheless, there are few reports on the use of high xylose concentrations . Considering a process in bioreactor, from rice straw hemicellulosic hydrolysate, this is an innovator work.

Lett Appl Microbiol, 2003, 37(2), 149 - 53
Microalgal-luffa sponge immobilized disc: a new efficient biosorbent for the removal of Ni(II) from aqueous solution; Akhtar N et al.; AIMS: The aim was to develop a new, efficient and cost-effective biosorbent for the removal of heavy metals from aqueous solution . METHODS AND RESULTS: A new biosorbent was developed by immobilizing a unicellular green microalga Chlorella sorokiniana within luffa sponge discs and used for the removal of metal ions from aqueous solution . Microalgal-luffa sponge immobilized discs (MLIDs) removed Ni(II) very rapidly, with 97% of equilibrium loading being reached in 5 min . MLIDs were tested for their potential to remove Ni(II) from aqueous solution in fixed-bed column bioreactor . The regenerated MLIDs retained 92.9% of the initial binding capacity for Ni(II) up to five cycles of reuse . CONCLUSIONS: In this study for the first time, C . sorokiniana biomass immobilized within luffa sponge disc was successfully used as a metal biosorbent for the removal of Ni(II) . It appears that MLIDs can be used as an effective biosorbent for efficient removal of Ni(II) or other metals from aqueous solution . SIGNIFICANCE AND IMPACT OF THE STUDY: MLIDs biosorption system was shown to have good biosorption properties with respect to Ni(II) . Efficient metal removal ability of MLIDs, low cost and simplicity of the technique used for the preparation of MILDs could provide an attractive strategy for developing high-affinity biosorption system for heavy metal removal.

Industrial processes using fermentation Fermentation by bacteria, yeast and mold is key to the production of fermented foods. Fermenting yeast produces the alcohol in beer and wine. In fact, the smell of fresh baked bread and rising dough can be attributed to alcohol produced from yeast. Fermentation is used to make many ethnic foods such as sauerkraut and miso. Soy sauce is produced by fermenting Aspergillus ortzae, a fungus, growing on soy beans. Erwinia dissolvens, another type of bacteria, is essential for coffee bean production; it is used to soften and remove the outer husk of beans. Finally, fermentation of milk produces most dairy products. Without microbes, we would not be able to eat many types of different food that we enjoy today. Table 1 shows example of several foods that are produced through fermentation with specific organisms.

In the majority of processes so far developed, the most effective, stable and convenient form for the catalyst has been the whole organism. It is for this reason that so much of biotechnology revolves around microbial processes. However, this does not exclude the use of higher organisms, in particular plant and animal cell culture that have played a vital role in the development of therapeutic and diagnostic biological products and will continue to play an increasingly important role in biotechnology.

The second part of the core of biotechnology deals with all aspects of the containment system or bioreactor within which the catalysts must function. Here the combined knowledge of the scientist and the bioprocess engineer interact, providing the design and instrumentation for the maintenance and control of physiochemical environment such as temperature, aeration, pH, etc., thus allowing the optimum expression of the biological properties of the catalyst.

The third aspect of the biotechnology, namely downstream processing, can be a technically difficult and expensive procedure. Downstream processing is primarily concerned with the initial separation of the bioreactor medium into a liquid phase and a solid phase, and subsequent separation, concentration and purification of the product. Chemical engineering principles play a vital role here as well in terms of designing and operation of the separation systems. Downstream processing costs can be as high as 60 - 70% of the selling price of the product as exemplified by the plant Eli Lilly built to produce human insulin. Over 90% of the 200 staff are involved in the recovery processes. Downstream processing represents a major part of the overall cost of most processes but is also the least glamorous aspect of biotechnology. Improvements in downstream processing will benefit the overall efficiency and cost of processes and will make the biotechnology competitive to the conventional chemical processes.

Taking a gene from one organism and inserting it into another is essentially a process of cutting the gene which codes for the trait of interest from the foreign organism and pasting this gene into the genome of the organism that you want to alter.

Let us use the insertion of B. thuringiensis genes into corn as an example. In order to cut out the gene of interest in the bacteria, its total DNA is isolated. Special enzymes, called restriction endonucleases, act as scissors to cut out the desired gene. These enzymes are sensitive to the DNA sequence and will only cut DNA at specific spots. There are many different enzymes that cut in different places, so the enzyme used depends on the sequence of DNA surrounding the desired gene.

Once the gene is cut out, scientists must make an “expression cassette.” This consists of additional DNA surrounding the gene so that the corn cell knows where the gene of interest begins and ends. The part that tells the corn cell where the gene begins is called the promoter and the end, the terminator. Once the expression cassette has been made, it is inserted into a plasmid. The plasmid is a parasitic circle of DNA present in bacteria. By putting the cassette into a plasmid, millions of copies of it can be made. These copies are then introduced into the host cell and get inserted into the genome. Cells which have successfully incorporated the foreign gene into their genome are then expanded in cell culture and used to generate new plants.

The ethics of GM Foods GM foods have been the subject of much controversy. Advocates feel that GM foods will help provide food to the world’s continually expanding population. Since the number of people on earth keeps increasing (over 6 billion, and expected to double within 50 years), and the amount of land suitable for farming remains constant, more food must be grown in the same amount of space. Genetic engineering can make plants that will give farmers better yields through several different methods.

Crops can be harmed or destroyed by many different factors. Insects, weeds, disease, cold temperatures and drought can all adversely affect plants resulting in lower yields for the farmer. Genetic engineering techniques can be used to introduce genes, creating plants that are resistant or tolerant to these factors. Bt corn is an example of the introduction of a pest resistance gene. Monsanto has created strains of soybeans, corn, canola and cotton that are resistant to the weed-killer Roundup®. The weed-killer can be sprayed over the entire crop, killing all plants except the transgenic crop intended to be grown. Scientists have also taken a gene from a cold-water fish and introduced it into potatoes to protect the seedlings against sudden frost. These methods all create plants that are more likely to survive and be healthy, thereby increasing the production of farmer’s fields.

Genetic modification can also be used to change the properties of the crop, adding nutrients, making them taste better, or reducing the growing time. A good example of adding nutrients to food is the development of “golden” rice. Many countries in the world rely on rice as their primary food source. Unfortunately, rice is missing many essential vitamins and minerals, so people whose diet is based on rice are often malnourished. One of the most severe consequences of this is blindness caused by vitamin A deficiency. Researchers at the Swiss Federal Institute of Technology Institute for Plant Sciences genetically engineered rice, making it high in vitamin A. The group hoped to distribute the rice for free to any third world country requesting it.

Bioengineering integrates physical, chemical, biochemical and mathematical competencies and expertise with engineering approaches for applications in the field of biology, medicine, health and food industry. 

Lynx Fine-Resolution Realtime synthetic-aperture radar (SAR) 
on a General Atomics I-GNAT

20/20 Vision Even On a Cloudy Day 
Scandia Technology v.1, n.4 Winter99-00

Lynx, a new fine-resolution, realtime synthetic-aperture radar (SAR) system, has been unveiled by Sandia National Laboratories and General Atomics of San Diego.

Designed to be mounted on both manned aircraft and unmanned aerial vehicles (UAVs), the 115-pound SAR is a sophisticated all-weather sensor capable of providing photographic-like images through clouds, rain or fog and in daytime or nighttime conditions, all in real-time. The SAR produces images of extremely fine resolution, far surpassing current industry standards for synthetic-aperture radar resolution. Depending on weather conditions and imaging resolution, the sensor can operate at a range of up to 85 kilometers.

“The Lynx represents a breakthrough on many fronts,” said Bill Hensley, Sandia project leader. “Because the image resolution is so fine and the instrument itself is so lightweight, it represents a technology breakthrough. The real-time, interactive nature of the radar and the innovative operator interface make it a breakthrough for meeting the ease-of-use needs of frontline military users. And because Sandia developed the technology and successfully transferred it to General Atomics, the Lynx radar also is a technology-transfer success story.”

Mike Reed, Lynx program manager at General Atomics, said that Sandia and General Atomics joined forces in 1996 when the San Diego-based company (whose Aeronautical Systems, Inc. affiliate builds a line of unmanned aerial vehicles) wanted to develop an advanced, lightweight SAR system. General Atomics provided the funds to Sandia, which already had a sophisticated SAR, to implement an enhanced design as a commercial product and deliver two prototype units together with licenses and manufacturing information to produce the unit.

The Lynx radar image shows 
the Rio Grande Valley

General Atomics and Sandia spent the next three years working together to refine and enhance the SAR into a lightweight, user-friendly system with extended range and much higher resolution. General Atomics has commenced production of subsequent units for commercial sales.

The new SAR will enhance the surveillance capability of the General Atomics Aeronautical Systems UAVs and other reconnaissance aircraft, which previously were equipped only with cameras, infrared sensors, and oldergeneration SAR equipment. “Cameras provided good data, but they don’t work at night or in rainy, foggy, and cloudy situations,” Hensley said. “Fineresolution- image SAR radar is perfect for these circumstances because it can ‘see’ in the dark and peer through clouds and fog.”

Flying at an altitude of 25,000 feet, the Lynx SAR can produce one-footresolution imagery at standoff distances of up to 55 kilometers. At a resolution of four inches, the radar can make images of scenes 25 kilometers away (about 16 miles) even through clouds and light rain.

The radar operates in Ku band with a center frequency of about 16.7 GHz, although the precise value can be tuned to prevent interference with other emitters.

Lynx introduces several new characteristics and functions. In addition to being very lightweight, the radar can detect very small changes in a scene by using a technique called coherent change detection. It also will be able to detect moving targets.

Sandia and General Atomics worked to make Lynx as much like an optical system to use as possible. The radar forms an image covering an area larger than that displayed, storing it in cache memory. This allows the operator to pan around within the total scene to concentrate on a particular area of interest. The radar’s fine resolution allows it to detect small surface penetrations — even footprints in a soft terrain.

Lynx has been flown successfully for more than 140 hours on a Department of Energy plane and on the General Atomics I-GNAT. In all testing, the SAR worked with the precision expected. Sandia and General Atomics continue to explore ways to improve the Lynx. Future upgrades could include an inverse SAR mode for imaging of seaborne targets, interferometric SAR (requiring the use of two antennas) for threedimensional imaging, the ability to cue other sensors, and radio-frequency tagging — both for combat identification and for precision-strike applications. Additional “cognitive” enhancements are planned to make interpretation of the radar image more user friendly.

General Atomics, founded in 1955, is involved in high-technology nuclear energy, commercial, and defense-related research and development. Affiliated manufacturing and commercial service companies include General Atomics Aeronautical Systems Inc., which builds the family of Predator, GNAT, Prowler, and Altus UAVs.