Friday, May 29, 2009

Robots with fins, tails demonstrate evolution


In this April 3, 2009 photo, Vassar biology and cognitive science professor John Long poses with Madeleine, a swimming robot, in a lab at Vassar College in Poughkeepsie, N.Y. Madeleine has four flippers sticking from its sides, and it was used to study a 45-ton marine reptile that patrolled the seas in the Jurassic Period. (AP Photo/Mike Groll)
(AP) -- Robots wag their tail fins and bob along like bathtub toys in a pool at a Vassar College lab. Their actions are dictated by microprocessors housed in round plastic containers, the sort you'd store soup in.
It hardly looks like it, but the two swimming robots were set loose in the little pool to study evolution, acting out predator-prey encounters from roughly 540 million years ago.
The prey , dubbed Preyro, can simulate evolution.
This is not like robot evolution in the "Terminator" movie sense of machines turning on their human masters. Instead, Vassar biology and professor John Long and his students can make changes to the tail of Preyro to see which designs help it avoid the predator robot.
"We're applying selection," Long explains, "just like natural selection."
Long is among a small group of researchers worldwide studying biology and evolution with the help of robots that can do things like shimmy through water or slither up shores. Long's robots, for instance, test theories on the development of stiffer backbones. The researchers believe the machines will catch on as technological advances allow robots to mimic animals far better than before.
Microprocessors are now tinier and more sophisticated. Building materials are more pliable. The same technology driving the use of electronic prosthetic limbs and vacuuming robots also is giving scientists a sophisticated tool to study biology.
"In the past, if you think about it, robots wouldn't work because we could only make these big metal things with rotating joints that were really stiff ... and that's not how nature is," said Robert J. Full, professor of integrative biology at the University of California, Berkeley.
Full's lab at Berkeley has built robots that can creep like cockroaches or climb like . In Switzerland, researchers built a bright yellow salamander robot a few years ago that can swim and walk to investigate vertebrates' transition from water to land. They posted a Web video of the robot squirming out of Lake Geneva.
At Harvard University, George Lauder, professor of organismic and evolutionary biology, studies fish locomotion with the aid of robotic fins. He says scientists are not trying to build spitting images of animals, but rather to mimic certain characteristics - a fin or a spinal column - to study how they work. Scientists then alter that characteristic to see how it affects performance.
The small amount of robot research performed so far has yet to dramatically alter evolutionary studies, but it has helped researchers evolve their understanding of some animals.
Consider Madeleine the swimming robot. Madeleine is roughly the size and shape of a big bed pillow with four flippers sticking from its sides, but it was used to study a 45-ton marine reptile that patrolled the seas in the Jurassic Period.
Fossil records show that the massive pliosaur, dubbed Predator X, had two sets of largely symmetrical flippers, indicating the animal used all four to swim. Long said that sets Predator X apart from modern animals like otters, sea lions and turtles, which tend to use one set of flippers for propulsion and the other for steering.
Researchers studying Predator X asked Long to investigate why the creature used all four flippers for swimming. Madeleine was programmed to swim with two flippers, then all four. The robot demonstrated that using four flippers to swim could be a bad proposition, energy-wise. But they do provide a sort of turbo-boost for quick accelerations - handy for catching dinner.
"The otter and the pliosaur both swim the same speed," Long said, "but, man, that pliosaur can really take off."
The Preyro robot experiment allows Long to take his evolutionary studies a step further.
By setting up Preyro in a pool with another autonomous robot - a predator named Tadiator - Long and his students simulated an evolutionary scenario. They wanted to examine qualities that would help vertebrate sea creatures of the Cambrian Period forage for food without becoming lunch for predators. Specifically, they wanted to test the hypothesis that the ancient creatures' need to scoot away fast from predators drove the evolution of stiffer tails.
Students could stiffen Preyro's backbone by fitting plastic rings (representing vertebrae) over a jelly-like column running down the tail designed to simulate the biological structures of ancient sea creatures. More rings made for a stiffer tail.
They found that changing the size of Preyro's tail fin had no effect, but that backbones stiffened with vertebrae helped Preyro swim away from danger faster. Seven vertebra worked the best; any more made the tail too stiff. They concluded that the of multiple vertebrae could have been influenced by the need to avoid predators while foraging.
Robot builders like Long still use computer simulations to complement their work. But Long says swimming robots like Madeleine and Preyro have advantages over computer simulations because it is extremely difficult to simulate the interaction between a flexible solid - like an animal's tail - and a liquid.
"The thing about robots is, robots can't violate the laws of physics," he said. "A computer program can."
Lauder said there's no substitute for building a device that can replicate the minutely complex features of an animal. He expects the rise of robots in biological research to accelerate as more advances are made.
"The next 20 years are going to be amazing, I think," Lauder said.
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On the Net:
http://faculty.vassar.edu/jolong/jolong.html

Saturday, May 16, 2009

Fujitsu develops world's fastest processor

(AP) -- Japanese computer maker Fujitsu Ltd. said Wednesday that it has successfully developed the world's fastest supercomputer processing unit with more than twice the speed of the current leader.
A new , or CPU, prototype successfully computed at 128 billion times per second - beating the current record, held by Intel Corp., by 2.5 times, company spokesman Masao Sakamoto said.
The company shrunk the size of each central circuit, thus doubling the number of circuits per chip, he said. The prototype is also energy-efficient and was able to cut power consumption to one-third of the conventional model.
Fujitsu aims to put the new CPU, with a code name "Venus," into practical application in supercomputers "within several years," Sakamoto said.
Computer makers, including IBM Corp., Cray Inc. and Intel, have been competing to develop a faster CPU.
Copyright 2009 Associated Press. All rights reserved. This material may not be published broadcast, rewritten, or redistributed.

Super-efficient Transistor Material Predicted


(PhysOrg.com) -- New work by condensed-matter theorists at the Stanford Institute for Materials and Energy Science at SLAC National Accelerator Laboratory points to a material that could one day be used to make faster, more efficient computer processors.
In a paper published online Sunday in , SIMES researchers Xiao-Liang Qi and Shou-Cheng Zhang, with colleagues from the Chinese Academy of Sciences and Tsinghua University in Beijing, predict that a room temperature material will exhibit the quantum spin Hall effect. In this exotic state of matter, flow without dissipating heat, meaning a transistor made of the material would be drastically more efficient than anything available today. This effect was previously thought to occur only at extremely low temperatures. Now the race is on to confirm the room-temperature prediction experimentally.
Zhang has been one of the leading physicists working on the quantum spin Hall effect; in 2006 he predicted its existence in mercury telluride, which experimentalists confirmed a year later. However, the mercury telluride had to be cooled by liquid helium to a frigid 30 millikelvins, much too cold for real-world applications.
In their hunt for a material that exhibited the quantum spin Hall effect, Zhang and Qi knew they were looking for a solid with a highly unusual energy landscape. In a normal semiconductor, the outermost electrons of an atom prefer to stay in the valence band, where they are orbiting atoms, rather than the higher-energy conduction band, where they move freely through the material. Think of the conduction band as a flat plain pitted with small valence-band valleys. Electrons naturally "roll" down into these valleys and stay there, unless pushed out. But in a material that exhibits the quantum spin Hall effect, this picture inverts; the valence-band valleys rise to become hills, and the electrons roll down to roam the now lower-energy conduction band plain. In mercury telluride, this inversion did occur, but just barely; the hills were so slight that a tiny amount of energy was enough to push the electrons back up, meaning the material had to be kept extremely cold.
When Zhang, Qi and their colleagues calculated this energy landscape for four promising materials, three showed the hoped-for inversion. In one, bismuth selenide, the theoretical conduction band plain is so much lower than the valence band hills that even room temperature energy can't push the electrons back up. In physics terms, the conduction band and valence band are now inverted, with a sizeable difference between them.
"The difference [from mercury telluride] is that the gap is much larger, so we believe the effect could happen at room temperature," Zhang explained.
Materials that exhibit the quantum spin Hall effect are called topological insulators; a chunk of this material acts like an empty metal box that's completely insulating on the inside, but conducting on the surface. Additionally, the direction of each electron's movement on the surface decides its spin, an intrinsic property of electrons. This leads to surprising consequences.
Qi likens electrons traveling through a metal to cars driving along a busy road. When an electron encounters an impurity, it acts like a frustrated driver in a traffic jam, and makes a U-turn, dissipating heat. But in a topological insulator, Qi said, "Nature gives us a no U-turn rule." Instead of reversing their trajectories, electrons cruise coolly around impurities. This means the quantum spin Hall effect, like superconductivity, enables current to flow without dissipating energy, but unlike superconductivity, the effect doesn't rely on interactions between electrons.
Qi points out that, because current only flows on their surfaces, topological insulators shouldn't be seen as a way to make more efficient power lines. Instead, these novel compounds would be ideal for fabricating tinier and tinier transistors that transport information via electron spin.
"Usually you need magnets to inject spins, manipulate them, and read them out," Qi said. "Because the current and spin are always locked [in a topological insulator], you can control the spin by the current. This may lead to a new way of designing devices like transistors."
These tantalizing characteristics arise from underlying physics that seems to marry relativity and condensed matter science. Zhang and Qi's paper reveals that electrons on the surface of a topological insulator are governed by a so-called "Dirac cone," meaning that their momentum and energy are related according to the laws of relativity rather than the quantum mechanical rules that are usually used to describe electrons in a solid.
"On this surface, the electrons behave like a relativistic, massless particle," Qi said. "We are living in a low speed world here, where nothing is relativistic, but on this boundary, relativity emerges."
"What are the two greatest physics discoveries of the last century? Relativity and quantum mechanics." Zhang said. "In the semiconductor industry in the last 50 years, we've only used quantum mechanics, but to solve all these interesting frontier problems, we need to use both in a very essential way."
Zhang and Qi's new predictions are already spurring a surge of experiments to test whether these promising materials will indeed act as room-temperature topological insulators.
"The best feedback you can get is that there are lots of experiments going on," he said.
More information: http://www.nature.com/nphys/journal/vaop/ncurrent/abs/nphys1270.html
Provided by SLAC National Accelerator Laboratory (news : web)

Friday, May 15, 2009

The Origin of Artificial Species: Creating Artificial Personalities


(Left) Rity was developed to test the world’s first robot “chromosomes,” which allow it to have an artificial genome-based personality. (Right) A representation of Rity’s artificial genome. Darker shades represent higher gene values, and red represents negative values. Image credit: Jong-Hwan Kim, et al. ©2009 IEEE.
(PhysOrg.com) -- Does your robot seem to be acting a bit neurotic? Maybe it's just their personality. Recently, a team of researchers has designed computer-coded genomes for artificial creatures in which a specific personality is encoded. The ability to give artificial life forms their own individual personalities could not only improve the natural interactions between humans and artificial creatures, but also initiate the study of “The Origin of Artificial Species,” the researchers suggest.
The first artificial creature to receive the genomic personality is Rity, a dog-like software character that lives in a virtual 3D world in a PC. Rity’s genome is composed of 14 chromosomes, which together are composed of a total of 1,764 genes, each with its own value. Rather than manually assign the gene values, which would be difficult and time-consuming, the researchers proposed an evolutionary process that generates a genome with a specific personality desired by a user. The process is described in a recent study by authors Jong-Hwan Kim of KAIST in Daejeon, Korea; Chi-Ho Lee of the Samsung Economic Research Institute in Seoul, Korea; and Kang-Hee Lee of Samsung Electronics Company, Ltd., in Suwon-si, Korea.
“This is the first time that an artificial creature like a or software agent has been given a genome with a personality,” Kim told PhysOrg.com. “I proposed a new concept of an artificial chromosome as the essence to define the personality of an artificial creature and to pass on its traits to the next generation, like a genetic inheritance. It is critical to provide an impression that the robot is a living creature. With this respect, having emotions enhances natural for human-robot symbiosis in the coming years.”
As the researchers explain, an autonomous artificial creature - whether a physical robot or agent - can behave, interact, and react to environmental stimuli. Rity, for example, can interact with humans in the physical world using information through a mouse, a camera, or a microphone, with 47 perceptions. For instance, a single click and double click on Rity are perceived as “patted” and “hit,” respectively. Dragging Rity slowly and softly is perceived as “soothed,” and dragging it quickly and wildly as “shocked.”
To react to these stimuli in real time, Rity relies on its internal states which are composed of three units - motivation, homeostasis, and emotion - and controlled by its internal control architecture. The three units have a total of 14 states, which are the basis of the 14 chromosomes: the motivation unit includes six states (curiosity, intimacy, monotony, avoidance, greed, and the desire to control); the homeostasis unit includes three states (fatigue, hunger, and drowsiness); and the emotion unit has five states (happiness, sadness, anger, fear, and neutral).
“In Rity, internal states such as motivation, homeostasis and emotion change according to the incoming perception,” Kim said. “If Rity sees its master, its emotion becomes happy and its motivation may be ‘greeting and approaching’ him or her. It means the change of internal states and the activated behavior accordingly is internal and external responses to the incoming stimulus.”
The internal control architecture processes incoming sensor information, calculates each value of internal states as its response, and sends the calculated values to the behavior selection module to generate a proper behavior. Finally, the behavior selection module probabilistically selects a behavior through a voting mechanism, where each reasonable behavior has its own voting value. Unreasonable behaviors are prevented with matrix masks, while a reflexive behavior module, which imitates an animal’s instinct, deals with urgent situations such as running into a wall and enables a more immediate response.
“Rity was developed to test the world's first robotic ‘chromosomes,’ which are a set of computerized DNA (Deoxyribonucleic acid) code for creating robots that can think, feel, reason, express desire or intention, and could ultimately reproduce their kind, and evolve as a distinct species in a virtual world,” Kim said. “Rity can express its feeling through facial expression and behavior just like a living creature.”
As the researchers explain, each of the 14 chromosomes in Rity’s genome is composed of three gene vectors: the fundamental gene vector, the internal-state-related gene vector, and the behavior-related gene vector. As each chromosome is represented by 2 F-genes, 47 I-genes, and 77 B-genes, Rity has 1,764 genes in total. Each gene can have a range of values represented by real numbers. While genes are inherited, mutations may also occur. The nature of the genetic coding is such that a single gene can influence multiple behaviors, and also a single behavior can be influenced by multiple genes.
Depending on the values of the genes, the researchers specified five personalities (“the Big Five personality dimensions”) and their opposites to classify an artificial creature’s personality traits: extroverted/introverted, agreeable/antagonistic, conscientious/negligent, openness/closeness, and neurotic/emotionally stable.
To demonstrate an artificial genome, the researchers used their evolutionary algorithm to generate two contrasting personalities for Rity - agreeable and antagonistic - and compare Rity’s behavior in the different cases. Running the algorithm through 3,000 generations took about 12 hours to generate a genome encoding a desired personality by a Pentium 4, 2 GHz processor. For comparison, the researchers also used manual and random processes to generate genomes with agreeable and antagonistic personalities, though neither outperformed the evolutionary algorithm in terms of personality consistency and similarity to desired personality. Finally, the researchers also verified the accuracy of the evolutionary genome encoding by observing how the artificial creature reacted to a series of stimuli.
“The genome is an essential one encoding a mechanism for growth, reproduction and evolution, which necessarily defines ‘The Origin of Artificial Species,’” Kim said. “It means the origin stems from a computerized genetic code, which defines the mechanism for growing, multiplying and evolving along with its propensity to ‘feel’ happy, sad, angry, sleepy, hungry, afraid, etc.”
As the researchers showed, a 2D representation of the genome can enable users to view the chromosomes of the three gene types and easily insert or delete certain chromosomes or genes related to an artificial creature’s personality.
In the future, the researchers plan to combine the genome-based personality with the artificial creature’s own experiences in order to influence the creature’s behavioral responses. They also plan to classify and standardize the different behaviors in order to generalize the artificial genome structure.
More information:
Robot Intelligence Technology Lab: http://rit.kaist.ac.kr/home/ArtificialCreatures
Jong-Hwan Kim, Chi-Ho Lee, and Kang-Hee Lee. “Evolutionary Generative Process for an Artificial Creature’s Personality.” IEEE Transactions on Systems, Man, and Cybernetics - Part C: Applications and Reviews, Vol. 39, No. 3, May 2009.
Copyright 2009 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.

Sunday, May 10, 2009

Microscope Capable Of Live Imaging At Double The Resolution Of Fluorescence Microscopy Developed

ScienceDaily (May 11, 2009) — A crucial tool in the evolution of scientific capability in bioscience, the fluorescence microscope has allowed a generation of scientists to study the properties of proteins inside cells. Yet as human capacity for discovery has zoomed to the nanoscale, fluorescence microscopy has struggled to keep up. Now, a team that includes UGA engineer Peter Kner has developed a microscope that is capable of live imaging at double the resolution of fluorescence microscopy using structured illumination.
The laws of physics have limited the resolution of fluorescence microscopy, whereby a fluorescent marker is used to distinguish specific proteins, to about 200 nanometers. At this resolution significant detail is lost about the activity within a cell. The increased resolution by structured illumination is an engineering feat that will help scientists learn more about cell behavior and study mechanisms important for human disease.
"Our understanding of what is going on inside cells and our ability to manipulate them has advanced so much that it has become more and more important to see them at a better resolution," said Kner, who joined UGA this spring semester. Kner built the structured illumination microscope with colleagues at the University of California, San Francisco.
This work follows on at least a decade of research building on the nearly fifty-year history of fluorescence microscopy. The technology has been a multi-disciplinary springboard of optical engineering, chemistry and biology, in which the disciplines have all contributed to visualizing fluorescent dyes attached to proteins, advancing our understanding of cellular activity. The importance of fluorescence microscopy was recently recognized with the 2008 Nobel Prize for Chemistry which was awarded for the development of the green fluorescent protein (GFP), which has played a crucial role in our identification and understanding of proteins.
"What we've done is develop a much faster system that allows you to look at live cells expressing GFP, which is a very powerful tool for labeling inside the cell," Kner explained.
"It would be difficult to overstate the importance of bio-imaging to ongoing research in human health," said Dale Threadgill, director of the UGA Faculty of Engineering. "The ability to shine a light on the leading-edge of scientific discovery will define the route to entirely new regimens of health management at the intersections of science and engineering, and Dr. Kner has joined a distinguished cadre at UGA to continue working at that interface," Threadgill added.
Journal reference:
Kner et al. Super-resolution video microscopy of live cells by structured illumination. Nature Methods, 2009; 6 (5): 339 DOI: 10.1038/nmeth.1324
Adapted from materials provided by University of Georgia, via EurekAlert!, a service of AAAS.

Faster Computers, Electronic Devices Possible After Scientists Create Large-area Graphene On Copper

ScienceDaily (May 11, 2009) — The creation of large-area graphene using copper may enable the manufacture of new graphene-based devices that meet the scaling requirements of the semiconductor industry, leading to faster computers and electronics, according to a team of scientists and engineers at The University of Texas at Austin.
"Graphene could lead to faster computers that use less power, and to other sorts of devices for communications such as very high-frequency (radio-frequency-millimeter wave) devices," said Professor and physical chemist Rod Ruoff, one of the corresponding authors on the Science article. "Graphene might also find use as optically transparent and electrically conductive films for image display technology and for use in solar photovoltaic electrical power generation."
Graphene, an atom-thick layer of carbon atoms bonded to one another in a "chickenwire" arrangement of hexagons, holds great potential for nanoelectronics, including memory, logic, analog, opto-electronic devices and potentially many others. It also shows promise for electrical energy storage for supercapacitors and batteries, for use in composites, for thermal management, in chemical-biological sensing and as a new sensing material for ultra-sensitive pressure sensors.
"There is a critical need to synthesize graphene on silicon wafers with methods that are compatible with the existing semiconductor industry processes," Ruoff said. "Doing so will enable nanoelectronic circuits to be made with the exceptional efficiencies that the semiconductor industry is well known for."
Graphene can show very high electron- and hole-mobility; as a result, the switching speed of nanoelectronic devices based on graphene can in principle be extremely high. Also, graphene is "flat" when placed on a substrate (or base material) such as a silicon wafer and, thus, is compatible with the wafer-processing approaches of the semiconductor industry. The exceptional mechanical properties of graphene may also enable it to be used as a membrane material in nanoelectromechanical systems, as a sensitive pressure sensor and as a detector for chemical or biological molecules or cells.
The university researchers, including post-doctoral fellow Xuesong Li, and Luigi Colombo, a TI Fellow from Texas Instruments, Inc., grew graphene on copper foils whose area is limited only by the furnace used. They demonstrated for the first time that centimeter-square areas could be covered almost entirely with mono-layer graphene, with a small percentage (less than five percent) of the area being bi-layer or tri-layer flakes. The team then created dual-gated field effect transistors with the top gate electrically isolated from the graphene by a very thin layer of alumina, to determine the carrier mobility. The devices showed that the mobility, a key metric for electronic devices, is significantly higher than that of silicon, the principal semiconductor of most electronic devices, and comparable to natural graphite.
"We used chemical-vapor deposition from a mixture of methane and hydrogen to grow graphene on the copper foils," said Ruoff. "The solubility of carbon in copper being very low, and the ability to achieve large grain size in the polycrystalline copper substrate are appealing factors for its use as a substrate --along with the fact that the semiconductor industry has extensive experience with the use of thin copper films on silicon wafers. By using a variety of characterization methods we were able to conclude that growth on copper shows significant promise as a potential path for high quality graphene on 300-millimeter silicon wafers."
The university's effort was funded in part by the state of Texas, the South West Academy for Nanoelectronics (SWAN) and the DARPA CERA Center. Electrical and computer engineering Professor Sanjay Banerjee, a co-author of the Science paper, directs both SWAN and the DARPA Center.
"By having a materials scientist of Colombo's caliber with such extensive knowledge about all aspects of semiconductor processing and now co-developing the materials science of graphene with us, I think our team exemplifies what collaboration between industrial scientists and engineers with university personnel can be," said Ruoff, who holds the Cockrell Family Regents Chair #7. "This industry-university collaboration supports both the understanding of the fundamental science as well its application."
Other co-authors of the work not previously mentioned include: research associate Richard Piner of the Department of Mechanical Engineering; Assistant Professor Emanuel Tutuc of the Department of Electrical and Computer Engineering; post-doctoral fellows Jinho An, Weiwei Cai, Inhwa Jung, Aruna Velamakanni and Dongxing Yang in the Department of Mechanical Engineering; and graduate students Seyoung Kim and Junghyo Nah in the Department of Electrical and Computer Engineering.
Journal reference:
Li et al. Large-Area Synthesis of High-Quality and Uniform Graphene Films on Copper Foils. Science, 2009; DOI: 10.1126/science.1171245
Adapted from materials provided by University of Texas at Austin, via EurekAlert!, a service of AAAS.

Sexually Transmitted Infections: Transistors Used To Detect Fungus Candida Albicans

SOURCE

ScienceDaily (May 11, 2009) — The Nanosensors group from the Universidad Rovira i Virgili has created a biosensor, an electrical and biological device, which is able to selectively detect the Candida albicans yeast in very small quantities of only 50 cfu/ml (colony-forming units per millilitre).
"The technique uses field-effect transistors (electronic devices that contain an electrode source and a draining electrode connected to a transducer) based on carbon nanotubes and with Candida albicans-specific antibodies", Raquel A. Villamizar, lead author of the study said.
The Candida samples, which can be obtained from blood, serum or vaginal secretions, are placed directly on the biosensor, where the interaction between antigens and antibodies changes the electric current of the devices. This change is recorded and makes it possible to measure the amount of yeast present in a sample.
"Thanks to the extraordinary charge transference properties of the carbon nanotubes, the fungus detection process is direct, fast, and does not require the use of any marker", remarks Villamizar, who is co-author of a study that provides details of the biosensor and was published recently in the journal Sensors and Actuators B: Chemical.
To date, conventional diagnosis of Candida has been carried out using microbial cultures, serological tests, PCR molecular biology techniques (polymerase chain reactions used to amplify DNA), or immunoassays such as ELISA (Enzyme Linked Inmunoabsorbent Assay).
These techniques require long analysis times and sometimes give rise to false positives and negatives. ELISA also requires the use of markers (compounds that must be added to detect the presence of yeast by fluorescence and other techniques).
The new carbon nanotubes biosensor, however, "makes it possible to improve some of the quality parameters of the traditional methods, for example the speed and simplicity of measurements, and it is an alternative tool that could be used in routine sample analysis", explains Villamizar.
The researcher adds that by using this biosensor "it will be possible in future to obtain a rapid diagnosis of infection with this pathogen, which will help to ensure administration of the correct prophylactic treatments".
The Candida albicans fungus exists naturally in the skin, mouth, the mucous membranes lining the digestive tract, and the respiratory and genitourinary systems. This yeast can cause anything from simple mycosis of the skin to complicated cases of candidiasis. It is much more commonly found in patients suffering from immunodeficiency, tumours, diabetes and lymphomas, among other diseases.
Journal reference:
Villamizar et al. Improved detection of Candida albicans with carbon nanotube field-effect transistors. Sensors and Actuators B Chemical, 2009; 136 (2): 451 DOI: 10.1016/j.snb.2008.10.013
Adapted from materials provided by Plataforma SINC.