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.

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 w