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Uses sound waves to convert waste heat directly into useable electricity. Working prototype; video; patent. Can be printed on microchip. Seeking licensees, developer partners, venture partners.
Quoting from: http://www.io.com/~frg/
This tiny MEMS thermoacoustic generator converts heat into electricity. The source of heat can be solar radiation, combustible fuel, even body heat. It requires no maintenance and is cost competitive with all existing power generation equipment.
The MEMS-TAR is manufactured using the same equipment and processes used in the manufacture of computer chips. It is packaged in single discrete units, and in integrated panel arrays. Power conditioning circuitry is built right into the chip.
Applications:
Telecommunications satellite power and space power applications.
Commercial power generation; Energy recovery (co-generation).
Solar electric and air-conditioning systems for individual homes, businesses and industry.
Biomedical prosthetics and artificial organs that operate from body heat.
Alarms, GPS locator beacons and physiological data transmitters.
Sensors and controls
Hundreds of consumer appliances and novelty items.
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The Techno Maestro's Amazing Machine
Kohei Minato and the Japan Magnetic Fan Company
A maverick inventor's breakthrough electric motor uses permanent magnets to make power -- and has investors salivating
by John Dodd
When we first got the call from an excited colleague that he'd just seen the most amazing invention -- a magnetic motor that consumed almost no electricity -- we were so skeptical that we declined an invitation to go see it. If the technology was so good, we thought, how come they didn't have any customers yet?
We forgot about the invitation and the company until several months later, when our friend called again.
"OK," he said. "They've just sold 40,000 units to a major convenience store chain. Now will you see it?"
In Japan, no one pays for 40,000 convenience store cooling fans without being reasonably sure that they are going to work.
The maestro
The streets of east Shinjuku are littered with the tailings of the many small factories and workshops still located there -- hardly one's image of the headquarters of a world-class technology company. But this is where we are first greeted outside Kohei Minato's workshop by Nobue Minato, the wife of the inventor and co-director of the family firm.
The workshop itself is like a Hollywood set of an inventor's garage. Electrical machines, wires, measuring instruments and batteries are strewn everywhere. Along the diagram-covered walls are drill presses, racks of spare coils, Perspex plating and other paraphernalia. And seated in the back, head bowed in thought, is the 58-year-old techno maestro himself.
Minato is no newcomer to the limelight. In fact, he has been an entertainer for most of his life, making music and producing his daughter's singing career in the US. He posseses an oversized presence, with a booming voice and a long ponytail. In short, you can easily imagine him onstage or in a convertible cruising down the coast of California -- not hunched over a mass of wires and coils in Tokyo's cramped backstreets.
Joining us are a middle-aged banker and his entourage from Osaka and accounting and finance consultant Yukio Funai. The banker is doing a quick review for an investment, while the rest of us just want to see if Minato's magnetic motors really work. A prototype car air conditioner cooler sitting on a bench looks like it would fit into a Toyota Corolla and quickly catches our attention.
Seeing is believing
Nobue then takes us through the functions and operations of each of the machines, starting off with a simple explanation of the laws of magnetism and repulsion. She demonstrates the "Minato Wheel" by kicking a magnet-lined rotor into action with a magnetic wand.
Looking carefully at the rotor, we see that it has over 16 magnets embedded on a slant -- apparently to make Minato's machines work, the positioning and angle of the magnets is critical. After she kicks the wheel into life, it keeps spinning, proving at least that the design doesn't suffer from magnetic lockup.
She then moves us to the next device, a weighty machine connected to a tiny battery. Apparently the load on the machine is a 35kg rotor, which could easily be used in a washing machine. After she flicks the switch, the huge rotor spins at over 1,500 rpms effortlessly and silently. Meters show the power in and power out. Suddenly, a power source of 16 watt or so is driving a device that should be drawing at least 200 to 300 watts.
Nobue explains to us that this and all the other devices only use electrical power for the two electromagnetic stators at either side of each rotor, which are used to kick the rotor past its lockup point then on to the next arc of magnets. Apparently the angle and spacing of the magnets is such that once the rotor is moving, repulsion between the stators and the rotor poles keeps the rotor moving smoothly in a counterclockwise direction. Either way, it's impressive.
Next we move to a unit with its motor connected to a generator. What we see is striking. The meters showed an input to the stator electromagnets of approximately 1.8 volts and 150mA input, and from the generator, 9.144 volts and 192mA output. 1.8 x 0.15 x 2 = 540mW input and 9.144 x 0.192 = 1.755W out.
But according to the laws of physics, you can't get more out of a device than you put into it. We mention this to Kohei Minato while looking under the workbench to make sure there aren't any hidden wires.
Minato assures us that he hasn't transcended the laws of physics. The force supplying the unexplained extra power out is generated by the magnetic strength of the permanent magnets embedded in the rotor. "I'm simply harnessing one of the four fundamental forces of nature," he says.
Although we learned in school that magnets were always bipolar and so magnetically induced motion would always end in a locked state of equilibrium, Minato explains that he has fine-tuned the positioning of the magnets and the timing of pulses to the stators to the point where the repulsion between the rotor and the stator (the fixed outer magnetic ring) is transitory. This creates further motion -- rather than a lockup. (See the sidebar on page 41 for a full explanation).
Real products
Nobue Minato leads us to the two devices that might convince a potential investor that this is all for real.
First, she shows us the cooling fan prototype that is being manufactured for a convenience store chain's 14,000 outlets (3 fans per outlet). The unit looks almost identical to a Mitsubishi-manufactured fan unit next to it, which is the unit currently in wide use. In a test, the airflow from both units is about the same.
The other unit is the car air conditioning prototype that caught our eye as we came in. It's a prototype for Nippon Denso, Japan's largest manufacturer of car air conditioners. The unit is remarkably compact and has the same contours and size as a conventional unit. Minato's manufacturing skills are clearly improving.
The banker and his investment
Minato has good reason to complain about Japan's social and cultural uniformity. For years, people thought of him as an oddball for playing the piano for a living, and bankers and investors have avoided him because of his habit of claiming that he'd discovered a breakthrough technology all by himself -- without any formal training.
However, the Osaka banker stands up after the lecture and announces that before he goes, he will commit \100 million to the investment pool.
Minato turns to us and smiles. We brought him good luck, and this was his third investor in as many weeks to confirm an interest.
Bringing the tech to the table
With the audience gone, we ask Minato what he plans to do to commercialize the technology. His game plan is simple and clear, he says. He wants to retain control, and he wants to commercialize the technology in Japan first -- where he feels he can ensure that things get done right. Why doesn't he go directly to the US or China? His experiences in both countries, he suggests, have been less than successful. "The first stage is critical in terms of creating good products and refining the technology. I don't want to be busy with legal challenges and IP theft while doing that."
Still, the export and licensing of the technology are on his agenda, and Minato is talking to a variety of potential partners in other countries.
Whereas another inventor might be tempted to outsource everything to a larger corporation, part of what drives Minato is his vision of social justice and responsibility. The 40,000 motors for the convenience store chain are being produced by a group of small manufacturers in Ohta-ku and Bunkyo-ku, in the inner north of Tokyo -- which is becoming a regional rust belt. Minato is seized with the vision of reinvigorating these small workshops that until the 80s were the bedrock of Japan's manufacturing and economic miracle. Their level of expertise will ensure that the quality of the motors will be as good as those from any major company.
International prep
Despite his plan to do things domestically first, Minato is well prepared for the international markets. He is armed with both six years of living and doing business in Los Angeles in the early 90s -- and with patent protection for over 48 countries. His is hardly a provincial perspective.
His US experience came after playing the piano for a living for 15 years. He began tinkering with his invention in the mid-70s. The idea for his magnetic motor design came from a burst of inspiration while playing the piano.
But Minato decided to drop everything in 1990 to help his daughter Hiroko, who at the age of 20 decided that she wanted to be a rhythm and blues star in the US. Minato is a strong believer in family: If Hiroko was going to find fame and fortune in the US, Dad had better be there to help manage her. He suceeded in helping Hiroko to achieve a UK dance chart number one hit in 1995.
In 1996 Minato returned to Japan and his magnetic motor project. The following year he displayed his prototypes to national power companies, government officials and others at a five-day conference in Mexico City. Interest was palpable, and Minato realized that his invention might meet a global need for energy-saving devices.
Subsequent previews and speeches in Korea and Singapore further consolidated his commitment to bringing the invention to fruition, and he was able to bring in several early-stage investors.
During the late 90s, Minato continued to refine his prototypes. He also stayed in constant contact with his lawyer, registering patents in major countries around the world. Through his experiences in the US he realized that legal protection was critical, even if it meant delaying release of the technology by a couple of years.
Ironically, by the time he'd won patents in 47 countries, the Japanese patent office turned him down on the grounds that "[the invention] couldn' t possibly work" and that somehow he was fabricating the claims.
But a few months later they were forced to recant their decision after the US patent office recognized his invention and gave him the first of two patents. As Minato notes: "How typical of Japan's small-minded bureaucrats that they needed the leadership of the US to accept that my invention was genuine."
By 2001, the Minatos had refined their motors and met enough potential investors to enter into a major international relationship, initially with a Saudi company, to be followed thereafter by companies in the US and elsewhere.
However, fate dealt the investors and Minato's business a serious blow when the World Trade Center was attacked in New York. The Saudis retreated, and Minato's plans fell back to square one.
Now Minato is once again ready to move. With the first order in the works and more orders pending successful prototypes, he has decided that investors don't have to be primary partners. He is actively accepting inquiries from corporate investors who can bring strategic advantages and corporate credibility with them. His company, Japan Magnetic Fan, will make a series of investment tie-up announcements in the first and second quarters of 2004.
Implications
Minato's motors consume just 20 percent or less of the power of conventional motors with the same torque and horse power. They run cool to the touch and produce almost no acoustic or electrical noise. They are significantly safer and cheaper (in terms of power consumed), and they are sounder environmentally.
The implications are enormous. In the US alone, almost 55 percent of the nation's electricity is consumed by electric motors. While most factory operators buy the cheapest motors possible, they are steadily being educated by bodies like NEMA (National Electrical Manufacturers Association) that the costs of running a motor over a typical 20-year lifespan comprise a purchase price of just 3 percent of the total, and electricity costs of 97 percent. It is not unusual for a $2,000 motor to consume $80,000 of electricity (at a price of .06 cents per kilowatt hour).
Since 1992, when efficiency legislation was put into place at the US federal level, motor efficiency has been a high priority -- and motors saving 20 percent or so on electrical bills are considered highly efficient. Minato is about to introduce a motor which saves 80 percent, putting it into an entirely new class: The $80,000 running cost will drop to just $16,000. This is a significant savings when multiplied by the millions of motors used throughout the USA and Japan -- and eventually, throughout the world.The devices
Minato's invention and its ability to use remarkably less power and run without heat or noise make it perfect for home appliances, personal computers, cellphones (a miniature generator is in the works) and other consumer products.
The magnetic motor will be cheaper than a standard motor to make, as the rotor and stator assemblies can be set into plastic housings, due to the fact that the system creates very little heat. Further, with the motor's energy efficiency, it will be well suited for any application where a motor has limited energy to drive it. While development is still focused on replacing existing devices, Minato says that his motor has sufficient torque to power a vehicle.
With the help of magnetic propulsion, it is feasible to attach a generator to the motor and produce more electric power than was put into the device. Minato says that average efficiency on his motors is about 330 percent.
Mention of Over Unity devices in many scientific circles will draw icy skepticism. But if you can accept the idea that Minato's device is able to create motion and torque through its unique, sustainable permanent magnet propulsion system, then it makes sense that he is able to get more out of the unit than he puts in in terms of elctrical power. Indeed, if the device can produce a surplus of power for longer periods, every household in the land will want one.
"I am not in this for the money," Minato says. "I have done well in my musical career, but I want to make a contribution to society -- helping the backstreet manufacturers here in Japan and elsewhere. I want to reverse the trends caused by major multinationals. There is a place for corporations. But as the oil industry has taught us, energy is one area where a breakthrough invention like this cannot be trusted to large companies."
Minato was once close to making a deal with Enron. But today, he is firmly on a mission to support the small and the independent -- and to go worldwide with them and his amazing machine. "Our plan is to rally smaller companies and pool their talent, and to one day produce the technology across a wide range of fields."How It Works = Magnets in Motion
Minato's Magnetic Motor is quite different from the four fundamental types of motors manufactured today. The most modern designs, be they AC or DC, servo or stepper, all fundamentally employ the same principle of electromagnetic force of attraction that was first discovered almost 200 years ago. Their designs all suffer significant losses in efficiency caused by the coils, the core, and consequent magnetic losses (eddy currents). These losses are typically given up as heat from the system.
Minato's magnetic motor uses magnetic repulsion as its core source of energy and suffers very few losses. It creates almost no heat, and is substantially more efficient (up to 330 percent) than conventional motors.
Most of Minato's test units consist of a three-layered, non-magnetic rotor fitted with powerful Sumitomo Neomax (neodymium-iron-boron) magnets located (for a duration of 5 degrees) every 175 degrees around the circumference of the rotor. The magnets possess a powerful force of 5,000 gauss and repulsively interact with the two diametrically opposed fixed electromagnetic stators. The rotor moves due to the stator electromagnets bouncing the rotor magnets away from the stators -- in the direction to which the rotor magnets are inclined. The stator electromagnets are pulsed at specific intervals and durations (about 10ms at start-up, and reducing in period to 2ms as the rotor reaches its natural speed), to make sure that they are only energized when facing a departing rotor magnet.
Minato overcame a number of obstacles that have stopped other inventors from realizing a magnetic motor earlier (although there have been a lot of attempts). The first is that the rotor magnets use repulsion and not attraction to reduce the amount of energy needed. Second, the positioning and angle of the magnets on the rotor are critical to providing the right "glancing" motion of rotor and stator fields, bouncing off each other to create repulsive (and thus motive) force. Also, the magnets have to be powerful, something that only became possible after neodymium magnets appeared in the 80s.
Minato overcame a number of obstacles that have stopped other inventors from realizing a magnetic motor earlier (although there have been a lot of attempts). The first is that the rotor magnets use repulsion and not attraction to reduce the amount of energy needed. Second, the positioning and angle of the magnets on the rotor are critical to providing the right "glancing" motion of rotor and stator fields, bouncing off each other to create repulsive (and thus motive) force. Also, the magnets have to be powerful, something that only became possible after neodymium magnets appeared in the 80s.
The north-south structure of any magnet can be maintained by making the rotor with three layers: a top layer with the north pole of the neomax magnets facing outwards, a non-magnetic layer, and a south pole outward-facing layer. These layers are aligned with the opposing north-south poles of the two electromagnets. The pulse timing on the electromagnets is the key to creating a "sweet spot" for the repulsion between rotor and stator. Timing is created by means of sensors picking up timing marks just before the rotor magnets appear.
The rotor is started and stopped by applying and removing energy to the two stator electromagnets. After a deceleration period, the rotor aligns with the magnets facing the iron cores of the stator electromagnets.
A New Type of Solar Cell
November 2004Scientists in Japan have made the first device that can convert solar energy into electricity and then store the resulting electric charge. The "photocapacitor" designed by Tsutomu Miyasaka and Takurou Murakami at Toin University in Yokohama could be used to power mobile phones and other hand-held devices (Appl. Phys. Lett. 85 3932).
Conventional solar cells need a secondary device, such as a battery, to store the electrical power generated from light. The photocapacitor combines the photoelectric and storage functions in a single structure.
The Japanese device consists of two electrodes -- a light-absorbing photoelectrode made of semiconducting titanium dioxide and a counterelectrode made of platinum coated glass -- separated by a resin film. Both electrodes include a porous layer of activated carbon that has a large surface area. All three layers are filled with an ionic solution and form a capacitor that has a light collection area of 0.64 square centimetres (see figure).
Photons are collected by photoreceptor dye molecules on the surface of the titanium dioxide layer. When exposed to light, electrons from the dye molecules are transferred to the conducting band in the titanium dioxide layer, thus producing a current. They then transfer to the activated carbon layer at the counterelectrode via an external circuit.
Conversely, the positively charged holes left behind are transferred to the carbon layer at the photoelectrode. The accumulation of positive and negative charges at different carbon layers therefore allows the device to store energy or charge like a capacitor. The energy can be released by simply discharging the device.
"The photocapacitor is twice as efficient as traditional silicon-based solar cells in utilising weak light," Miyasaka told PhysicsWeb. "This means that it can utilise indirect sunlight, for example on cloudy or rainy days, and even indoor light. Moreover, it can release electrical energy anytime, even in the dark."
Miyasaka says that the next goal is to increase the charging voltage and the charge-discharge capacity to a practically and industrially useful level for applications.Solar cell edges towards endless energy
A limitless source of clean-burning fuel is a step closer following the discovery of a material that can extract hydrogen from water using energy from visible light. Zhigang Zou of the National Institute of Advanced Industrial Science and Technology in Japan and colleagues have developed a photocatalyst that uses optical radiation – which makes up 43% of solar energy. A reliable source of hydrogen is one of the ‘holy grails’ of energy production – hydrogen releases lots of energy when it burns and the only by-product is water. Previous catalysts have only responded to ultraviolet radiation, which accounts for just 4% of the Sun’s energy (Z Zou et al 2001 Nature 414 625).
Clean and green
Photocatalysis is the use of energy from absorbed light to initiate chemical reactions. Semiconductors are useful in such reactions because they can be designed so that their electronic characteristics change when they absorb radiation. But their energy bandgaps are often large, and this means that only photons with short-wavelengths and high-energies – such as ultraviolet photons – can promote electrons from the valence band to the conduction band.
To create a suitable material, Zou and co-workers added nickel to the semiconductor indium tantalum oxide. This reduced its energy bandgap from 2.6 to 2.3 electronvolts, which means that visible photons carry enough energy to make electrons jump the bandgap. They immersed this semiconductor in water and illuminated it with an arc lamp. As the semiconductor absorbs energy from the photons, electrons jump from the valence band to the conduction band, leaving positive holes in the valence band.
Provided the conduction band is at a higher energy than the ‘reduction potential’ of hydrogen, the ‘promoted’ electrons drift to the surface of the semiconductor where they combine with hydrogen ions in the water to make hydrogen gas. To balance this reaction, the valence band must be at a lower energy than the ‘oxidation potential’ of oxygen – this allows the positive holes to surface and accept electrons from oxygen ions in the water, creating oxygen gas.
The new semiconductor is also resilient – existing semiconductors that use visible light either corrode or become inert when they come into contact with water. Zou and colleagues point out that although their set-up is only 0.66% efficient, they are confident that this will improve when they increase the surface area of the semiconductor, and adjust its layout.
Siemens gearless generator boosts efficiency to 98%
EE Times
2004WASHINGTON — A gearless synchronous generator developed by Germany's Siemens and recently installed in a Norwegian wind power plant has achieved an efficiency rating of 98 percent, the company said.
Standard generators use a gearbox between the slow rotor and the fast generator to convert wind energy to electricity. But they lose energy to friction and heat.
The Siemens gearless generator uses permanent magnets to convert wind energy from the rotor to electricity. The design avoids losses to friction and heat and operates with only low winds or in brief gusts, the company said.
The gearless generator developed by Siemens' Automation and Drives unit was installed in April in the world's largest wind power plant in Hundhammerfjell, Norway. The plant has a power output of 3 megawatts, enough for its operator, the Swedish-Norwegian company ScanWind, to supply about 3,000 Norwegian households with electricity each year.Electronics, Biology: Twins under the Skin
October 27,2004
By Chappell BrownLike the twin strands of a double helix, electronics and biotechnology are joining forces in a technological explosion that experts say will dwarf what is possible for either one of them alone.
Hints of this pairing can be seen in the economic recovery that's now taking hold. One peculiarity that hasn't grabbed many headlines is biotech's role in pulling Silicon Valley out of its three-year slump. A report last month from the nonprofit organization Joint Venture: Silicon Valley Network points up this fact, showing that venture funding in biotech startups rose from 7 percent in 2000 to 24 percent last year while investment in information technology startups fell from 10 percent to 4 percent over the same period. The immediate question is whether this is a temporary anomaly or the emergence of a major trend.
Certainly computers, biochips, robotics and data sharing over the Internet have been important tools in accelerating biological and medical research, and it should be no surprise that new application areas and markets would grow around them. The view from inside the engineering cubicle might be something like, "Yes, we have created a revolutionary technology that creates new markets-biomedicine is simply one area that benefits from advances in VLSI."
But a long-term perspective suggests a tighter linkage between electronics technology and molecular biology. Indeed, it could be argued that the second half of the 20th century forged not one but two digital revolutions, fueled by two fundamental breakthroughs: transistorized digital computers and the cracking of the genetic code. The latter advance showed that the genome was transmitted through the generations by means of digital storage in the DNA molecule.
In the following decades, both developments matured at an increasingly rapid pace. Digital circuits were inspired by crude models of the nervous system (see story, below). Although the models turned out to be wrong in many respects, technologists discovered that digital representation brings the advantages of simplicity, stability and an ability to control errors. Those same properties have made DNA the viable and stable core of living systems for billions of years.
But the nervous system is only one component of the body that is encoded in DNA, which somehow not only represents the information for building the basic components of cells, but also encodes the entire process of assembling highly complex multicellular machines. The growth process is an amazing feat of bootstrapping from the genetic code to functioning organisms. Essentially, an organism is a molecular digital computer that constructs itself as part of the execution of its code.
Leroy Hood, director of the Institute for Systems Biology (Seattle), believes that science aided by computers and VLSI technology will achieve major breakthroughs in reverse-engineering the cell's assembly processes. The fallout will be new circuit and computational paradigms along with nanoscale mechanisms for building highly compact molecular computing machines.
"There will be a convergence between information technology and biotechnology that will go both ways," said Hood. "We can use new computational tools to understand the biological computational complexities of cells, and when we understand the enormous integrative powers of gene regulatory networks we will have insights into fundamentally new approaches to digital computing and IT."
But cell machinery can also be enlisted in the kind of nanostructure work that is currently done manually with tools such as the atomic-force microscope. "The convergence of materials science and biotech is going to be great, and we will be able to learn from living organisms how they construct proteins that do marvelous things and self-assemble," Hood said. "There will be lessons about how to design living computer chips that can self-assemble and have enormous capacity."
Hood is credited with inventing the automated DNA-sequencing systems that were the first step in accelerating the decoding of the human genome. Accomplished two years ahead of schedule thanks to many enhancements to the process, including MEMS-based microfluidic chips, the achievement has stimulated efforts to take on the far more complex task of decoding protein functions.
Hood's institute, which was founded in 2000, is one example of a wave of similar organizations springing up across the United States. The idea is to engage a diverse group of specialists-mechanical and electronic engineers, computer scientists, chemists, molecular biologists-in the effort to decode the cellular-growth process. Stanford University's BIO-X Biosiences Initiative, for example, is dedicated to linking life sciences, physical sciences, medicine and engineering. The Department of Energy's Pacific Northwest National Laboratory has its Biomolecular Systems Initiative, Princeton University its Lewis-Sigler Institute for Integrative Genomics. Harvard Medical School now has a systems-biology department, and MIT has set up its Computational and Systems Biology Initiative (CSBi).
Proteins have remarkable chemical versatility and go far beyond other molecules as chemical catalysts, said Peter Sorger, director of MIT's CSBi. But applications of their properties will have to contend with a difficult cost differential between medical and industrial products.
"Using proteins as catalysts was the absolute beginning of the biotech industry. We know that proteins are the most extraordinary catalysts ever developed. The problem is that most of the chemical industry is a low-margin business and biology has historically been very expensive," Sorger explained.
While organic catalysts derived from oil are not as efficient, the low cost of producing them has kept proteins out of the field. "Most of the applications of proteins to new kinds of polymers, new plastics, biodegradable materials, etc. have all been limited by the fundamental economic problem that oil is so darn cheap," he said. "As a result, bioengineered materials are only used in very high-end, specialized applications."
However, Sorger believes that such bioengineered products will arrive, probably first in biomedical applications, which will then spawn low-end mass-market products. He used the example of Velcro, which was devised as an aid to heart surgery and later became a common material in a wide range of commercial goods. Sorger is looking forward to nanotechnology applications, the assembly of materials and circuits using biological processes, as the first direct applications of protein engineering outside of the biomedical field.
Sorger cited the work of MIT researcher Angela Belcher as an example of the technological spin-offs that will come from attempts to understand cellular processes. Working in the cross-disciplinary areas of inorganic chemistry, biochemistry, molecular biology and electrical engineering, Belcher has found ways to enlist cellular processes to assemble structures from inorganic molecules. By understanding how cells direct the assembly of their structural components, Belcher is finding ways to assemble artificial materials from inorganic nanoclusters that can function as displays, sensors or memory arrays. Another interdisciplinary group at MIT is putting together a library of biological components that engineers could used to build artificial organisms able to accomplish specific nanoscale tasks.
Underlying the excitement surrounding the merger of digital electronics systems and molecular digital organisms are the dramatic capabilities of lab-on-a-chip chemical-analysis systems, automated data extraction and supercomputer data processing. These technologies are part of what made it possible to sequence the entire human genome. A benchmark for the rapid progress promised by those tools may be the announcement by three biotech companies late last year of single chips containing the human DNA molecule in addressable format-the human genome on a chip. That might compare to the advent of of the CPU-on-a-chip, which catalyzed the VLSI revolution in the mid-1970s.
The barrier to moving this capability forward lies in the physical differences between DNA and the proteins it codes. Proteins are built from DNA sequences as linear sequences of amino acids that then spontaneously fold into complicated 3-D shapes. And the process becomes more complex as proteins begin to interact with one another. For example, there is a feedback loop in which proteins regulate the further expression of proteins by DNA. As a result, there are no parallel fluidic-array techniques to accelerate the analysis of protein families. "These technologies have a long way to go. I don't see any fundamental breakthroughs [in protein analysis] in the next few years, but in 10 years, who knows?" said Steven Wiley, director of the Biomolecular Systems Initiative at Pacific Northwest National Laboratory. "There are a lot of smart people out there working on this."
The fundamental challenge is the dynamic aspect of protein function. "DNA is static; once you sequence it, you have it," Wiley said. But proteins "are constantly interacting, so you have to run multiple experiments to observe all their functions and you end up with multiple terabytes of information. So, how are you going to manage and analyze all this information?"
But the excitement generated by recent successes with the genome is contagious. Plans are afoot to decode the "language" of proteins, making their functions widely available to engineers; anyone with a personal computer and a modem can access the human genome over the Internet; lab-on-a-chip technology continues to reduce the cost of bioexperimentation while ramping up throughput. And there is venture capital funding out there.
DNA change could lead to life-shortening risk factors
Oct 23 2004Researchers have demonstrated that any change in a person's DNA can contribute to a range of life- shortening risk factors, including high blood pressure, high cholesterol, and other metabolic disorders. The mutation affects the genes of the mitochondria which is the energy-producing power plants of the cell that are passed from mother to offspring. The researchers are hopeful their discovery could help unravel the complex genetic and environmental factors that cause a range of metabolic disorders. The researchers, led by Howard Hughes Medical Institute investigator Richard P. Lifton, who is at Yale University School of Medicine, published their findings October 22, 2004, in Science Express, an online component of the journal Science. Gerald I. Shulman, another HHMI investigator at the Yale School of Medicine, was also an author on the paper.
"Epidemiological studies over the last twenty years have shown that hypertension, high cholesterol, high triglycerides, low magnesium, diabetes, insulin resistance, and obesity tend to cluster with one another, but not in a simple way," said Lifton. "Not everybody who has any one of these traits has all of the others. The pattern of inheritance is complicated, and there hasn't been a clear understanding of what's driving this relationship."
Such a pattern immediately suggested a defect in the mitochondrial genome, because those genes are uniquely passed from mother to offspring, unlike the rest of the cell's genome, which is contained in the nucleus. Once the researchers determined that a mitochondrial defect caused diverse traits, like an increased prevalence of hearing loss, migraine headaches, and weakened heart muscle, which are all known to be associated with genetic mutations in mitochondria.
The discovery of the genetic defect could open new avenues for basic research and treatment and could help explain why problems such as hypertension increase with age. The mutation could, for example, link hypertension to the age-related decline in mitochondrial function.Chips Coming To A Brain Near You
10-22-4In this era of high-tech memory management, next in line to get that memory upgrade isn't your computer, it's you.
Professor Theodore W. Berger, director of the Center for Neural Engineering at the University of Southern California, is creating a silicon chip implant that mimics the hippocampus, an area of the brain known for creating memories. If successful, the artificial brain prosthesis could replace its biological counterpart, enabling people who suffer from memory disorders to regain the ability to store new memories. And it's no longer a question of "if" but "when." The six teams involved in the multi-laboratory effort, including USC, the University of Kentucky and Wake Forest University, have been working together on different components of the neural prosthetic for nearly a decade. They will present the results of their efforts at the Society for Neuroscience's annual meeting in San Diego, which begins Saturday.
While they haven't tested the microchip in live rats yet, their research using slices of rat brain indicates the chip functions with 95 percent accuracy. It's a result that's got the scientific community excited. "It's a new direction in neural prosthesis," said Howard Eichenbaum, director of the Laboratory of Cognitive Neurobiology at Boston University. "The Berger enterprise is ambitious, aiming to provide a prosthesis for memory. The need is high, because of the prevalence of memory disorder in aging and disease associated with loss of function in the hippocampus."
Forming new long-term memories may involve such tasks as learning to recognize a new face, or remembering a telephone number or directions to a new location. Success depend on the proper functioning of the hippocampus. While this part of the brain doesn't store long-term memories, it re-encodes short-term memory so it can be stored as long-term memory.
It's the area that's often damaged as a result of head trauma, stroke, epilepsy and neurodegenerative disorders such as Alzheimer's disease. Currently, no clinically recognized treatments exist for a damaged hippocampus and the accompanying memory disorders. Berger's team began its research by studying the re-encoding process performed by neurons in slices of rat hippocampi kept alive in nutrients. By stimulating these neurons with randomly generated computer signals and studying the output patterns, the group determined a set of mathematical functions that transformed any given arbitrary input pattern in the same manner that the biological neurons do. And according to the researchers, that's the key to the whole issue.
"It's an impossible task to figure out what your grandmother looks like and how I would encode that," said Berger. "We all do a lot of different things, so we can't create a table of all the things we can possibly look at and how it's encoded in the hippocampus. What we can do is ask, 'What kind of transformation does the hippocampus perform?'
"If you can figure out how the inputs are transformed, then you do have a prosthesis. Then I could put that into somebody's brain to replace it, and I don't care what they look at -- I've replaced the damaged hippocampus with the electronic one, and it's going to transform inputs into outputs just like the cells of the biological hippocampus."
Dr. John J. Granacki, director of the Advanced Systems Division at USC, has been working on translating these mathematical functions onto a microchip. The resulting chip is meant to simulate the processing of biological neurons in the slice of rat hippocampus: accepting electrical impulses, processing them and then sending on the transformed signals. The researchers say the microchip is doing exactly that, with a stunning 95 percent accuracy rate.
"If you were looking at the output right now, you wouldn't be able to tell the difference between the biological hippocampus and the microchip hippocampus," Berger said. "It looks like it's working."
The team next plans to work with live rats that are moving around and learning, and will study monkeys later. The researchers will investigate drugs or other means that could temporarily deactivate the biological hippocampus, and implant the microchip on the animal's head, with electrodes into its brain.
"We will attempt to adapt the artificial hippocampus to the live animal and then show that the animal's performance -- dependent in these tasks on an intact hippocampus -- will not be compromised when the device is in place and we temporarily interrupt the normal function of the hippocampus," said Sam A. Deadwyler, "thus allowing the neuro-prosthetic device to take over that normal function." Deadwyler, a professor at Wake Forest University, is working on measuring the hippocampal neuron activity in live rats and monkeys.
The team expects it will take two to three years to develop the mathematical models for the hippocampus of a live, active rat and translate them onto a microchip, and seven or eight years for a monkey. They hope to apply this approach to clinical applications within 10 years. If everything goes well, they anticipate seeing an artificial human hippocampus, potentially usable for a variety of clinical disorders, in 15 years.
Overall, experts find the results promising.
"We are nowhere near applicability," said Boston University's Eichenbaum. "But the next decade will prove whether this strategy is truly feasible."
"There is a big gap in making the microchip work in a slice preparation and getting it to work in a human being," added Norbert Fortin, a neuroscientist from the Cognitive Neurobiology Lab at Boston University. "However, their approach is very methodical, and it is not unreasonable to think that in 15 to 20 years such a chip could help, to some degree, a patient who suffered from hippocampal damage."
