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Chemists are several steps closer to teasing hydrogen fuel from water using man-made molecular devices that collect electrons and use them to split hydrogen from oxygen.
Electrons are negatively charged particles that allow atoms to react and form bonds. Karen Brewer, professor of chemistry, announced at last August's ACS meeting that her group was able to use light to initiate electron collection and deliver the electrons to the catalyst site where they can be used to reduce water to hydrogen.
"Light energy is converted to chemical energy."
In the past year, the group has come up with additional molecular assemblies that absorb light more efficiently and activate conversion more efficiently.
Quantum communication networks show great promise in becoming a highly secure communications system. By carrying information with photons or atoms, which are entangled so that the behavior of one affects the other, the network can easily detect any eavesdropper who tries to tap the system.
Physicists at the Georgia Institute of Technology have just reached an important milestone in the development of these systems by entangling a photon and a single atom located in an atomic cloud. Researchers believe this is the first time an entanglement between a photon and a collective excitation of atoms has passed the rigorous test of quantum behavior known as a Bell inequality violation. The findings are a significant step in developing secure long-distance quantum communications.
Relying on photons or atoms to carry information from one place to another, network security relies on a method known as quantum cryptographic key distribution. In this method, the two information-carrying particles, photonic qubits or atomic qubits, are entangled. Because of the entanglement and a rule in quantum physics that states that measuring a particle disturbs that particle, an eavesdropper would be easily detected because the very act of listening causes changes in the system.
The military?s next generation of airborne drones won?t be just small and silent ? they?ll also dive between buildings, zoom under overpasses and land on apartment balconies.
Funded by the U.S. Air Force and NASA, University of Florida aerospace engineers have built prototypes of 6-inch- to 2-foot- drones capable of squeezing in and out of tight spots in cities ? like tiny urban stunt planes. Their secret: seagull-inspired wings that "morph," or change shape, dramatically during flight, transforming the planes? stability and agility at the touch of a button on the operator?s remote control.
"If you fly in the urban canyon, through alleys, around parking garages and between buildings, you need to do sharp turns, spins and dives. That means you need to change the shape of the aircraft during flight."
A special stretch of genetic material may turn off the immune suppression that stymies attempts to fight cancer with a vaccine, said researchers at Baylor College of Medicine (BCM) at Houston.
In a report in today's issue of the journal Science, Dr. Rong-Fu Wang, a professor in the BCM Center for Cell and Gene Therapy and Department of Immunology, and his colleagues describe a new strategy to turn off the function of a special group of T cells to suppress immune response to tumors and even infectious diseases.
"Since 1995, many groups have tried to develop a vaccine for the treatment of cancer. The only problem is that after 10 years of clinical trials, the data suggest that you can induce (cancer) antigen-specific immune responses, but such responses are too weak and transient to eradicate tumor cells."
"In fact, in some cases, this treatment actually enhanced anti-tumor immunity."
Researchers from Queen?s University and the Georgia Institute of Technology have discovered a new environmentally-friendly way to make chemicals for pharmaceutical and other industries, such as plastics, pesticides, dyes and fragrances.
The team, led by Queen?s chemist Dr. Philip Jessop, has developed new solvents (liquids that dissolve other substances) that are both cleaner and cheaper when used in the production of many chemicals. Because each step in a chemical process often requires a different solvent, there can be a great deal of waste which is both costly and damaging to the environment.
"We all want the products of the plastics and pharmaceutical industries, but we don?t want the pollution. Our research is seeking ways to decrease the amount of solvent waste generated by these companies."
Imagine this: A tiny, fast switch that uses water droplets to create adhesive bonds almost as strong as aluminum by borrowing a mechanism found in palm beetles.
The new beetle-inspired switch, designed by Cornell University engineers, can work by itself on the scale of a micron -- a millionth of a meter. The switches can be combined in arrays for larger applications like powerful adhesive bonding. Like the transistor, whose varied uses became apparent only following its invention, the uses of the new switch are not yet understood. But the switch's simplicity, smallness and speed have enormous potential, according to the researchers.
"Almost all the greatest technological advances have depended on switches, and this is a switch that is fast and can be scaled down."
Applications are envisioned in the areas of mechanics, micro-fluidics and optics, among others.
A team of researchers from the Ecole Polytechnique F?d?rale de Lausanne (EPFL) has successfully demonstrated, for the first time, that it is possible to control the speed of light ? both slowing it down and speeding it up ? in an optical fiber, using off-the-shelf instrumentation in normal environmental conditions. Their results could have implications that range from optical computing to the fiber-optic telecommunications industry.
On the screen, a small pulse shifts back and forth ? just a little bit. But this seemingly unremarkable phenomenon could have profound technological consequences. It represents the success of Luc Th?venaz and his fellow researchers in the Nanophotonics and Metrology laboratory at EPFL in controlling the speed of light in a simple optical fiber. They were able not only to slow light down by a factor of three from its well ? established speed c of 300 million meters per second in a vacuum, but they've also accomplished the considerable feat of speeding it up ? making light go faster than the speed of light.
Trials have begun in Kansas on a "green" production method for succinate, a key ingredient of many plastics, drugs, solvents and food additives. Developed at Rice University, the technology uses a genetically modified form of the bacteria E. coli that metabolizes glucose and produces almost pure succinate.
Finding "green" methods to make key chemical intermediates like succinate is a high priority for the chemical industry. Green technologies use renewable resources like agricultural crops rather than non-renewable fossil fuels, and they produce less waste.
"Succinate is a high-priority chemical that the U.S. Department of Energy has targeted for biosynthesis. One reason for this is succinate's broad utility -- it can be used to make everything from non-corrosive airport deicers and non-toxic solvents to plastics, drugs and food additives. Succinate's also a priority because some bacteria make it naturally, so we have a metabolic starting place for large-scale fermentation."
Chemists at the University of California, Riverside have synthesized a new class of carbenes ? molecules that have unusual carbon atoms ? that is expected to have wide applications in the pharmaceutical industry, ultimately resulting in a reduction in the price of drugs.
Called cyclic alkyl amino carbenes or CAACs, the molecules attach themselves to metals, such as palladium, to form highly efficient catalysts that allow chemical transformations otherwise considered impossible. The carbenes modulate the properties of the metals to which they are bound and can facilitate and speed up reactions involving their use.
A carbene is a molecule that has a carbon atom with six electrons instead of the usual eight. Because of the electron deficiency, carbenes are highly reactive and usually unstable in nature.
In a groundbreaking experiment, researchers from the City College of New York (CCNY) and Lehman College have measured the speed of magnetic avalanches and discovered that the process is analogous to the flame front of a flammable substance. The discovery of a "magnetic flame" could make it easier for engineers to study the dynamics of fire.
Magnetic avalanches occur when the polarity of a molecular nanomagnet is changed suddenly and sufficient energy is released to cause a chain reaction that changes the polarity of the other molecular nanomagnets in a crystal.
A breakthrough in human stem cell research, producing embryonic-like cells from umbilical cord blood may substantially speed up the development of treatments for life-threatening illnesses, injuries and disabilities. The discovery provides medical researchers and physicians with an ethical and reliable source of human stem cells for the first time.
The study represents a significant step forward in the fast-developing field of stem cell research. Until now, experts have struggled to find a supply of cells in sufficient numbers that does not offend previous critics of stem cell research. The latest advance looks set to overcome such difficulties.
The researchers findings may bring renewed hope to people awaiting treatment for a range of serious illnesses such as Diabetes, Alzheimer's Disease and multiple sclerosis.
Scientists will announce next month a new technique called microdisplacement printing, which makes possible the highly precise placement of molecules during the fabrication of nanoscale components for electronic and sensing devices. The new technique also extends the library of molecules that can be used for patterning.
"We have mapped out strategies in this model system and are now investigating how we can apply these strategies more broadly as the chemistry is developed for self-assembled monolayers on other substrates, especially semiconductors. Our goals are to see how far we can take these kinds of simple techniques, along with our knowledge of intermolecular interactions, to bridge the 1-to-100-nanometer length scale in nanofabrication, which even at the high end currently requires very difficult, slow, and expensive techniques."
The new microdisplacement technique is based on a widely used patterning method known as microcontact printing--a simple way of fabricating chemical patterns that does not require clean rooms and other kinds of special and expensive environments. Both methods involve "inking" a patterned rubber-like stamp with a solution of molecules, then applying the inked stamp to a surface.
Scientists using NASA's Swift satellite say they have found newborn black holes, just seconds old, in a confused state of existence. The holes are consuming material falling into them while somehow propelling other material away at great speeds.
These black holes are born in massive star explosions. An initial blast obliterates the star, yet the chaotic black hole activity appears to re-energize the explosion several times in just a few minutes. This is a dramatically different view of star death, one that entails multiple explosive outbursts and not just a single bang, as previously thought.
"Stars are exploding two, three and sometimes four times in the first minutes following the initial explosion. First comes a blast of gamma rays followed by intense pulses of X-rays. The energies involved are much greater than anyone expected."
Scientists have seen this phenomenon in nearly half of the longer gamma-ray bursts detected by Swift. These gamma-ray bursts are the most powerful explosions known. They are forerunners of a massive star explosion called a hypernova, which is bigger than a supernova. Using Swift, scientists are finally able to see gamma-ray bursts within minutes after the trigger, instead of hours or days, and are privy to newborn black hole activity.
Researchers at Stanford University have demonstrated a promising, minimally invasive optical technique that can capture micron-scale images from deep in the brains of live subjects. The method, called two-photon microendoscopy, combines a pair of powerful optical and mechanical techniques into one device that fits in the palm of the hand.
Researchers want to image individual cells inside living subjects because it will give them insight into how cellular behavior gives rise to the properties of organisms as a whole. For instance, the nerve cells of the hippocampus region of the brain give rise to important mental processes such as learning and memory.
"This is a portable handheld device with the power of two-photon imaging -- the full functionality of a microscope that fits in the palm of your hand."
In an unusual collaboration among scientists and humanists, a Cornell University team has demonstrated a novel method for recovering faded text on ancient stone by zapping and mapping 2,000-year-old inscriptions using X-ray fluorescence (XRF) imaging.
The research, carried out at the Cornell High Energy Synchrotron Source (CHESS), applies a nondestructive chemical analysis technique widely used in geology, archaeology and materials science.
"X-ray fluorescence imaging has the potential to become a major tool in epigraphy [the study of incised writing on various surfaces, including stone]. It's just so much more powerful than anything that's been used in the past."
The article describes the first successful application of XRF imaging to the study of ancient stone inscriptions between 1,800 and 2,400 years old. It will be published in August in Zeitschrift fur Papyrologie und Epigraphik (journal for papyrology and epigraphy) , one of the world's leading journals on ancient texts. The discovery could herald an important breakthrough in the study of ancient cultures.
Researchers at UT Southwestern Medical Center have identified a biochemical switch that affects how neurons fire in a part of the brain associated with learning, findings that may aid in understanding schizophrenia and Alzheimer's disease.
The research sheds new light on the action of reelin, a protein known to be important in the nervous system. During development, reelin sends cues to migrating neurons, telling them where they're supposed to go. In adult mice, reelin has recently been implicated in the formation of memories, and reduced production of reelin has been associated with schizophrenia in humans.
(Picture: Lung cells derived from stem cells.)
Scientists have successfully converted human embryonic stem cells into lung cells, taking a first step towards building human lungs for transplantation.
According to research to be published in the journal Tissue Engineering, the team from Imperial College London, took human embryonic stem cells and 'directed' them to convert into the type of cells needed for gas exchange in the lung, known as mature small airway epithelium.
Dame Professor Julia Polak, from Imperial College London, who led the research team, says:
"This is a very exciting development, and could be a huge step towards being able to build human lungs for transplantation or to repair lungs severely damaged by incurable diseases such as cancer."
Scientists at the Woods Hole Research Center are producing a high-resolution "National Biomass and Carbon Dataset" for the year 2000 (NBCD2000), the first ever inventory of its kind. Through a combination of NASA satellite datasets, topographic survey data, land use/land cover data, and extensive forest inventory data collected by the U.S. Forest Service, this "millennium" dataset will serve as an invaluable baseline for carbon stock assessment and flux modeling in the United States.
The NBCD2000 project draws on vegetation canopy height estimated from digital elevation data collected during the 2000 Shuttle Radar Topography Mission, which mapped 80 percent of the Earth's land mass with a radar instrument, producing the most complete digital surface map of Earth. In combination with the National Land Cover Database 2001(NLCD2001) and the National Elevation Dataset (NED), both generated by the U.S. Geological Survey, and forest survey data from the U.S. Forest Service, a high-resolution database of circa-2000 vegetation canopy height, aboveground biomass, and carbon stocks for the conterminous United States will be generated, providing an unprecedented baseline against which to compare data products from the next generation of advanced Earth observing remote sensing platforms.
Dr. Josef Kellndorfer, an associate scientist with the Woods Hole Research Center, is leading the project.
"The generation of this first-of-its-kind, high-resolution data set for the United States for the year 2000 will enable unprecedented quantification of biomass and carbon stocks, and will improve many more related studies ranging from carbon-climate interactions, forest fire mitigation, and wildlife habitat characterization, to national energy policy with respect to bio-fuel and renewable resources."
Heat has always been a problem for fuel cells. There?s usually either too much (ceramic fuel cells) for certain portable uses, such as automobiles or electronics, or too little (polymer fuel cells) to be efficient.
While polymer electrolyte membrane (PEM) fuel cells are widely considered the most promising fuel cells for portable use, their low operating temperature and consequent low efficiency have blocked their jump from promising technology to practical technology.
But researchers at the Georgia Institute of Technology have pinpointed a chemical that could allow PEM fuel cells to operate at a much higher temperature without moisture, potentially meaning that polymer fuel cells could be made much more cheaply than ever before and finally run at temperatures high enough to make them practical for use in cars and small electronics.
Scientists funded by NASA have made big strides in learning how to forecast "all clear" periods, when severe space weather is unlikely. The forecasts are important because radiation from particles from the sun associated with large solar flares can be hazardous to unprotected astronauts, airplane occupants and satellites.
"We have a much better insight into what causes the strongest, most dangerous solar flares, and how to develop forecasts that can predict an 'all clear' for significant space weather, for longer periods."
Solar flares are violent explosions in the atmosphere of the sun caused by the sudden release of magnetic energy. Like a rubber band twisted too tightly, stressed magnetic fields in the sun?s atmosphere (corona) can suddenly snap to a new shape. They can release as much energy as one, 10 billion megaton nuclear bomb.
Predicting space weather is a complicated problem. Solar forecasters focus principally on the complexity of solar magnetic field patterns to predict solar storms. This method is not always reliable, because solar storms require additional ingredients to occur. It has long been known large electrical currents must be present to power flares.
Data from the NASA/ESA/ASI Cassini spacecraft indicate that Saturn's majestic ring system has its own atmosphere - separate from that of the planet itself.
During its close fly-bys of the ring system, instruments on Cassini have been able to determine that the environment around the rings is like an atmosphere, composed principally of molecular oxygen.
This atmosphere is very similar to that of Jupiter's moons Europa and Ganymede.
The finding was made by two instruments on Cassini, both of which have European involvement: the Ion and Neutral Mass Spectrometer (INMS) has co-investigators from USA and Germany, and the Cassini Plasma Spectrometer (CAPS) instrument has co-investigators from US, Finland, Hungary, France, Norway and UK.
A team of researchers from the UK and France used SOHO, ACE and the four Cluster spacecraft to study a huge eruption on the Sun, tracing its progress from birth to when it reached Earth.
The team, led by scientists from University College London, identified the source of a ?coronal mass ejection? (CME) and analysed how its magnetic field changes on its path to Earth.
Triggered by a massive explosion on the Sun with millions of times more energy than a nuclear bomb, these CMEs are blasts of gas that could engulf Earth. CMEs are caused by the collision of loop-like magnetic field lines with different polarities on the Sun?s surface.
"There?s been much speculation about the shape of the magnetic field and how it might change on its journey from the Sun to Earth. Using complementary satellites we have been able to see that the magnetic field changes very little on its journey."
Earth?s magnetic field, forming the magnetosphere, protects the planet from the full brunt of these blasts, but when the CME?s fields collide directly with it they can excite geomagnetic storms. In extreme cases they cause electrical power outages and damage to communications networks and satellites.
Researchers have developed a new technique for creating human embryonic stem cells by fusing adult somatic cells with embryonic stem cells. The fusion causes the adult cells to undergo genetic reprogramming, which results in cells that have the developmental characteristics of human embryonic stem cells.
This approach could become an alternative to somatic cell nuclear transfer (SCNT), a method that is currently used to produce human stem cells. SCNT involves transferring the nuclei of adult cells, called somatic cells, into oocytes in which scientists have removed the nuclei.
"Our assays showed that the hybrid cells, unlike adult cells, showed the development potential of embryonic stem cells. We found they could be induced to mature into nerve cells, hair follicles, muscle cells and gut endoderm cells. And, since these cell types are derived from three different parts of the embryo, this really demonstrated the ability of these cells to give rise to a variety of different cell types."
Engineers at Purdue University have created a nanotech simulation tool that shows how current flows between silicon atoms and individual molecules to help researchers design "molecular electronic" devices for future computers and advanced sensors.
Molecular electronics could make it possible to manufacture hardware by "growing" circuits and devices in layers that may "self-assemble," similar to the growth of structures in living organisms. Devices for a variety of applications might be fabricated using techniques based on chemical attractions rather than the complex, expensive processes now used to etch electronic circuits.
One challenge, however, in developing molecular electronics is to better understand how electricity is conducted between molecules and silicon contacts connecting various devices in a circuit, said Geng-Chiau Liang, a postdoctoral research assistant in Purdue's School of Electrical and Computer Engineering.
Researchers will be able to use the new simulation tool to see precisely how electrical conductivity changes depending on how molecules are connected to silicon, information that is critical to properly design the devices.
"I believe we might be one of the first theorists who have created a tool to show how electricity is conducted between molecules and silicon at the atomic level."
Lymph circulates in our bodies through a complex network of lymphatic vessels, of which little is known. This network is, however, of major importance for the support of the immune system and the fluid in our body.
Researchers from the Flanders Interuniversity Institute for Biotechnology (VIB) connected with the Catholic University of Leuven, are the first to indicate that this network can be studied with the help of tadpoles. This accelerates research of the lymphatic vessel network. With tadpoles one can now very quickly identify new genes that play a part in the development and functioning of the lymphatic vessel network.
This is a first step in the search for solutions for illnesses related to the lymphatic vessel network, such as cancer and lymphedema.
With the help of NASA's Spitzer Space Telescope, astronomers have conducted the most comprehensive structural analysis of our galaxy and have found tantalizing new evidence that the Milky Way is much different from your ordinary spiral galaxy.
The survey using the orbiting infrared telescope provides the fine details of a long central bar feature that distinguishes the Milky Way from more pedestrian spiral galaxies.
"This is the best evidence ever for this long central bar in our galaxy."
Using the orbiting infrared telescope, the group of astronomers surveyed some 30 million stars in the plane of the galaxy in an effort to build a detailed portrait of the inner regions of the Milky Way. The task, according to astronomers, is like trying to describe the boundaries of a forest from a vantage point deep within the woods:
"This is hard to do from within the galaxy."
Spitzer's capabilities, however, helped the astronomers cut through obscuring clouds of interstellar dust to gather infrared starlight from tens of millions of stars at the center of the galaxy. The new survey gives the most detailed picture to date of the inner regions of the Milky Way.
University of Texas at Dallas (UTD) nanotechnologists and an Australian colleague have produced transparent carbon nanotube sheets that are stronger than the same-weight steel sheets and have demonstrated applicability for organic light-emitting displays, low-noise electronic sensors, artificial muscles, conducting appliqu?s and broad-band polarized light sources that can be switched in one ten-thousandths of a second.
Carbon nanotubes are like minute bits of string, and untold trillions of these invisible strings must be assembled to make useful macroscopic articles that can exploit the phenomenal mechanical and electronic properties of the individual nanotubes.
Starting from chemically grown, self-assembled structures in which nanotubes are aligned like trees in a forest, the sheets are produced at up to seven meters per minute by the coordinated rotation of a trillion nanotubes per minute for every centimeter of sheet width. By comparison, the production rate for commercial wool spinning is 20 meters per minute. Unlike previous sheet fabrication methods using dispersions of nanotubes in liquids, which are quite slow, the dry-state process developed by the UTD-CSIRO team can use the ultra-long nanotubes needed for optimization of properties.
Strength normalized to weight is important for many applications, especially in space and aerospace, and this property of the nanotube sheets already exceeds that of the strongest steel sheets and the Mylar and Kapton sheets used for ultralight air vehicles and proposed for solar sails for space applications, according to the researchers. The nanotube sheets can be made so thin that a square kilometer of solar sail would weigh only 30 kilograms. While sheets normally have much lower strength than fibers or yarns, the strength of the nanotube sheets in the nanotube alignment direction already approaches the highest reported values for polymer-free nanotube yarns.
A University of Toronto scientist has found unexpectedly ?young? material in meteorites ? a discovery that breaks open current theory on the earliest events of the solar system.
A paper reports that the youngest known chondrules ? the small grains of mineral that make up certain meteorites ? have been identified in the meteorites known as Gujba and Hammadah al Hamra.
Researchers who have studied chondrules generally agree that most were formed as a sudden, repetitive heat, likely from a shock wave, condensed the nebula of dust floating around the early Sun. Thinking that an analysis of the chondrules in Gujba and Hammadah al Hamra would be appropriate for accurately dating this process, U of T geologist Yuri Amelin, together with lead author Alexander Krot of the University of Hawaii, studied the chondrules? mineralogical structure and determined their isotopic age.
"It soon became clear that these particular chondrules were not of a nebular origin. And the ages were quite different from what was expected. It was exciting."
Amelin explains that not only were these chondrules not formed by a shock wave, but rather emerged much later than other chondrules.
"They actually post-date the oldest asteroids. We think these chondrules were formed by a giant plume of vapour produced when two planetary embryos, somewhere between moon-size and Mars-size, collided."
What does this mean in the grand scheme of things? The evolution of the solar system has traditionally been seen as a linear process, through which gases around the early sun gradually cooled to form small particles that eventually clumped into asteroids and planets. Now there is evidence of chondrules forming at two very distinct times, and evidence that embryo planets already existed when chondrules were still forming.
"It moves our understanding from order to disorder. But I?m sure that as new data is collected, a new order will emerge."
Left: The CNGS target unit consists of a series of 10-cm long graphite rods distributed over a length of 2-m. It is designed to maximise the number of secondary particles produced and hence the number of neutrinos.
Scientists at CERN1 today announced the completion of the target assembly for the CERN neutrinos to Gran Sasso project, CNGS. On schedule for start-up in May 2006, CNGS will send a beam of neutrinos through the Earth to the Gran Sasso laboratory 730km away in Italy in a bid to unravel the mysteries of nature?s most elusive particles.
CNGS forms a unique element in the global effort to understand neutrinos, the chameleons of the fundamental particle world. Neutrinos come in three types, or flavours, and have the ability to change between one flavour and another. Neutrinos interact hardly at all with other matter. Trillions of them pass through us every second, and it is precisely their vast numbers that make them a key element in understanding the Universe and its evolution.
"Using mini gene and new systemic approach treated animals were significantly improved, lived longer."
Researchers from the University of Pittsburgh report the first study to achieve success with gene therapy for the treatment of congenital muscular dystrophy (CMD) in mice, demonstrating that the formidable scientific challenges that have cast doubt on gene therapy ever being feasible for children with muscular dystrophy can be overcome. Moreover, their results, published in this week's online edition of the Proceedings of the National Academy of Sciences (PNAS), indicate that a single treatment can have expansive reach to muscles throughout the body and significantly increase survival.
CMD is a group of some 20 inherited muscular dystrophies characterized by progressive and severe muscle wasting and weakness first noticed soon after birth. No effective treatments exist and children usually die quite young.
Despite gene therapy being among the most vigorously studied approaches for muscular dystrophy, it has been beset with uniquely difficult hurdles. The genes to replace those that are defective in CMD are larger than most, so it has not been possible to apply the same methods successfully used for delivering other types of genes. And because CMD affects all muscles, an organ that accounts for 40 percent of body weight, gene therapy can only have real therapeutic benefit if it is able to reverse genetic defects in every cell of the body's 600 muscle groups.
There are four wings to the Earth Science building of the Goddard Space Flight Center (GSFC) in Greenbelt, MD. But on August 8, "we added a virtual fifth wing," says NASA Emeritus Scientist Milton Halem. That new wing used experimental OptIPuter software to create a 'high-performance collaboratory' with the University of California, San Diego's Scripps Institution of Oceanography, which allowed scientists to establish high-definition telepresence while also collaborating in real time on visualizing massive amounts of remote land and weather data.
Working closely with researchers at the California Institute for Telecommunications and Information Technology (Calit2) at UCSD and Electronic Visualization Laboratory (EVL) at the University of Illinois at Chicago (UIC), GSFC networking and visualization staff conducted the first successful system test of a new coast-to-coast, 10-Gigabit per second (Gbps) Ethernet cyber backplane ? or 'lambda' ? linking the NASA research center to UCSD some 3,000 miles away.
"It's one of those quantum leaps that come along only once in a long while."
Every hour more energy from sunlight strikes the Earth than is consumed on the planet in a year. Yet today, solar electricity provides only approximately one thousandth of the total electricity supply.
To help achieve the goal of increased use of solar and other renewable forms of energy, the Department of Energy's (DOE) Office of Science has released a report describing the basic research needed to produce "revolutionary progress in bringing solar energy to its full potential in the energy marketplace." The report resulted from a workshop of 200 scientists held earlier this year.
"This research will help improve a critical component of renewable energy, solar technology, in the future. Increasing the use of renewable energy is a clear way to help meet our growing energy needs using environmentally-friendly power sources."
The interest of University of Akron polymer researchers in the fascinating ability of geckos to climb any surface and hang from just one toe soon could lead to advances in adhesives used in microelectronics and space applications.
The UA researchers are part of a team developing synthetic hairs from carbon nanotubes that have adhesion forces 200 times higher than those observed with gecko foot-hairs.
"It is well known that insects such as beetles and reptiles such as geckos have evolved and developed this most effective adhesive system in order to survive. The biological system in these creatures has perfected not only the mechanism to attach to steep vertical surfaces but also to detach at will."
Zo?, an autonomous solar-powered rover, is equipped with scientific instruments to seek and identify micro-organisms and to characterize their habitats. It will use them as it explores three diverse regions of the desert during its two-month stay in Chile.
Carnegie Mellon University researchers and their colleagues from NASA's Ames Research Center, the universities of Tennessee, Arizona and Iowa, as well as Chilean researchers at Universidad Catolica del Norte (Antofagasta) are preparing for the final stage of a three-year project to develop a prototype robotic astrobiologist, a robot that can explore and study life in the driest desert on Earth.
The results of this expedition ultimately may enable future robots to seek life on Mars, as well as enabling the discovery of new information about the distribution of life on Earth.
A system that allows surgeons to perform laparoscopic gastric bypass surgery from a remote console, controlling up to three robotic arms and a binocular camera, was successfully tested in 10 patients.
The laparoscopic gastric bypass surgery (a Roux-en-Y procedure) is often considered the most challenging minimally invasive procedure in general surgery, requiring a learning curve of 75 to100 cases for even experienced surgeons to achieve the highest level of proficiency, according to background information in the article. Although robotic surgical techniques have been developed to assist laparoscopic gastric bypass surgery, the complex geometry of the surgery has required repositioning of the robot, complicating its use.
"The median length of time to complete the procedure was significantly shorter with the robot (169 vs. 208 minutes)."
"Reluctance to use new technology such as the ? surgical robot often reflects surgeon concern over increasing complication rates, increased operative times, and steep learning curves.
"Any new technology must be proven feasible and safe. Our results support the robot's feasibility in the Roux-en-Y gastric bypass as we achieved comparable operating room times with an extremely short learning curve."
"Likewise, both major and minor complications were similar between the robotic and laparoscopic group, suggesting that a totally robotic laparoscopic gastric bypass is a safe and potentially superior alternative to traditional laparoscopic gastric bypass."
Physicists in Singapore have succeeded in creating the first paper battery that generates electricity from urine. This new battery will be the perfect power source for cheap, disposable healthcare test-kits for diseases such as diabetes. This research is published today in the Institute of Physics' Journal of Micromechanics and Microengineering.
Scientists in research groups around the world are trying to design ever smaller "biochips" that can test for a variety of diseases at once, give instant results, and, crucially, can be mass produced cheaply. But until now, no one has been able to solve the problem of finding a power source as small and as cheap to fabricate as the detection technology itself.
Led by Dr Ki Bang Lee, a research team at Singapore's Institute of Bioengineering and Nanotechnology (IBN) have developed a paper battery that is small, cheap to fabricate, and which ingeniously uses the fluid being tested (urine) as the power source for the device doing the testing.
University of Florida engineers have developed a compound that forces clothes in the washer to shed 20 percent more water during the spin cycle than in normal conditions. The result: A load of clothes dries faster in the dryer, saving energy ? and reducing homeowners? electricity bills and time spent in the laundry room.
The researchers? key insight was that the spaces between tiny fibers in the weave of fabrics comprise minute tubes, or capillaries, which retain water due to surface tension. It?s the same phenomenon that causes a submerged straw to hold water when covered at the other end and lifted out of the surface.
The researchers reasoned that reducing this surface tension would reduce the water retained by fabric. They first tested this idea using finger-sized copper containers dotted with drain holes. Filled with fabric and water and placed in a centrifuge, the containers mimicked the conditions of spin cycling washing machines ? except that the water loss and fabric retention could be easily measured.
When the researchers discovered that some compounds apparently increased water loss, they expanded their experiments to bigger fabrics and a real washer and dryer. The dryer sits in a crowded lab on a scale, allowing Carter to compare different wet loads by weight to their total drying times.
Their experiments revealed that one ratio of a common detergent and fabric softener ? five parts detergent, one part fabric softener ? added before the spin cycle forced the clothes to shed 20 percent more water than untreated clothes. The clothes then dried 20 percent faster.
"The small size and dramatic switching behavior of these nanotubes makes them candidates for a new class of transistor."
Researchers at UCSD and Clemson University have discovered that specially synthesized carbon nanotube structures exhibit electronic properties that are improved over conventional transistors used in computers. They reported that Y-shaped nanotubes behave as electronic switches similar to conventional MOS (metal oxide semiconductor) transistors, the workhorses of modern microprocessors, digital memory, and application-specific integrated circuits.
"This is the first time that a transistor-like structure has been fabricated using a branched carbon nanotube. This discovery represents a new way of thinking about nano-electronic devices, and I think people interested in creating functionality at the nanoscale will be inspired to explore the ramifications of these Y-junction elements in greater detail."
New discoveries about the timing and speed of gigantic, 6500-foot (2-km) thick lava flows that poured out of the ground 65 million years ago could shift the blame for killing the dinos.
The new work on the Deccan Traps is just the latest in a series of discoveries which appear to weaken the case implicating the Chicxulub impact as the primary player in the Cretaceous-Tertiary (K-T) mass extinction.
The Deccan Traps of India are one of Earth's largest lava flows ever, with the potential of having wreaked havoc with the climate of the Earth - if they erupted and released climate-changing gases quickly enough. French and Indian geologists have now identified a 600-meter (2000-foot) thick portion of the lava that may have piled up in as little as 30,000 years - fast enough to have possibly caused a deadly global climate shift.
"Our working hypothesis is that the majority of the total volume of lava might have been erupted in only a few major events spread over only a small fraction of millennia."
Physicists at the University of Texas at Austin have discovered a new technique for cooling atoms and molecules that will allow them to study quantum physics more effectively with a greater variety of particles.
The researchers have found a way to use lasers to form walls that allow atoms and molecules to pass through in one direction, but do not allow them to return.
The technique could lead to advances in atomic clocks, which are used to standardize time worldwide.
Every year, the world consumes over 880 billion pounds of rice, which feeds half the population. Those tiny grains add up. So maybe it's no surprise that this important food crop turns out to have more genes than humans.
The completed sequence, published in the August 11 issue of Nature, unveils a genome consisting of roughly 400 million DNA bases holding 37,544 genes on rice's 12 chromosomes.
"Rice is a critically important crop, and this finished sequence represents a major milestone. We know the scientific community can use these data to develop new varieties of rice that deliver increased yields and grow in harsher conditions."
Over the next 20 years, world rice production must increase by a projected 30% to feed the earth's growing population.
This finished sequence will provide an indispensable roadmap to agricultural researchers using both biotechnology and conventional breeding to develop hardier rice varieties. The genetic map will greatly speed their hunt for genes that increase yield, protect against disease and pests, or provide drought-resistance in rice and other cereal crops.
"Much as the Human Genome Project has revolutionized biology, the rice genome promises to inspire new cereal crop research. This is a major step forward for agriculture."
Already, in fact, the finished rice genome is accelerating discovery. Scientists have used the finished sequence to identify genes that control fundamental processes, such as flowering. Rice's similarity to barley also has helped researchers identify genes responsible for resistance to barley powdery mildew and stem rust, two major crop diseases.
The San Andreas Fault Observatory at Depth (SAFOD) reached a significant goal when scientists drilled into a seismically active section of the fault approximately two miles below the surface of the Earth.
"For the first time, scientists have drilled directly into the San Andreas Fault Zone at a depth that will allow us to observe earthquakes up close for decades to come."
"We've looked at the fossil earthquakes, we've made computer models, and we've made laboratory earthquakes. We've studied them from afar, but we've never been inside the machine where the action is."
When completed in 2007, SAFOD will be the only earthquake observatory with instruments installed directly within an active fault where earthquakes form or "nucleate."
SAFOD instrumentation will provide around-the-clock observations of temperature, fluid pressure, strain accumulation and other processes before, during and after microearthquakes occur.
When drilling is completed in August, the entire borehole will be encased in steel and cement so that sensitive instruments--such as seismometers, strainmeters, and fluid and temperature gauges--can be installed underground. Meanwhile, scientists will begin to collect rock, gas and mineral samples from the fault zone for laboratory analysis.
Physicists at the National Institute of Standards and Technology (NIST) have used charged atoms (ions) to demonstrate a quantum physics version of computer memory lasting longer than 10 seconds--more than 100,000 times longer than in previous experiments on the same ions.
The advance improves prospects for making practical, reliable quantum computers (which make use of the properties of quantum systems rather than transistors for performing calculations or storing information).
Quantum computers, if they can be built, could break today's best encryption systems, accelerate database searching, develop novel products such as fraud-proof digital signatures or simulate complex biological systems to help design new drugs.
A unique 'fingerprint' formed by microscopic surface imperfections on almost all paper documents, plastic cards and product packaging could be used as a cheaper method to combat fraud, scientists suggest.
This inherent identity code is virtually impossible to modify and can be easily read using a low-cost portable laser scanner, according to research carried out at Imperial College London and Durham University, and published in Nature today.
Researchers believe the technology could also prove valuable in the fight against terrorism through the ability to secure passports, ID cards and 'breeder' documents such as birth certificates used to obtain genuine passports.
Scientists studying the structure and interaction of negatively charged lipids and DNA molecules have created a "cookbook" for a class of nontoxic DNA delivery systems that will assist doctors and clinicians in the safe and effective delivery of genetic medicine.
Researchers have now performed a careful, comprehensive study to see how negatively charged lipids stick to negatively charged DNA and self-organize into structures.
"Many research groups have made concoctions with ingredients in different proportions and then assessed their effectiveness in gene delivery, but this is hard and requires a lot of intuition."
"By understanding some of the physics, we now have recipes for assembling delivery systems with different structures, which can have intrinsically different, controllable DNA delivery efficiencies. We found that the same family of structures are generated for many different ions."
Monash University scientists have rejuvenated the immune systems of mice and humans using a common hormone.
The scientists, led by Associate Professor Richard Boyd and Dr Jayne Sutherland from the Monash Immunology and Stem Cell Laboratories, have revitalised the thymus which produces the T cells required to fight infection but which shuts down from early adulthood.
Their achievement has offered new hope for patients with cancer, AIDS and other immunodeficiencies and for transplant patients.
A simple tank-and-siphon system for removing oil from oily water and protecting the environment is about to be launched internationally by an engineering team from the University of New South Wales.
The Extended Gravity Oil Water Separation (EGOWS) concept is an improvement on the industry-standard American Petroleum Institute (API) gravity separator that has been widely used for the last 60 years.
The API separator, originally designed for oil refineries, is not designed to reduce the oil content of water below about 100 parts per million and is not suitable for releasing water directly to the environment.
Regulatory requirements for the release of oil-contaminated water to the environment are becoming stricter worldwide. It is common for environmental protection authorities to impose a limit of 10 parts of oil per million of effluent water, and increasingly for there to be no visible sheen on the receiving water.
The figure is famous: a deceptively simple line drawing that at first glance resembles a vase and, at the next, a pair of human faces in profile. When you look at this figure, your brain must rapidly decide what the various lines denote. Are they the outlines of the vase or the borders of two faces? How does your brain decide?
It does so in a fraction of a second via special nerve circuits in the brain's visual center that automatically organize information into a "whole" even as an individual's gaze and attention are focused on only one part, according to Johns Hopkins researchers.
"Early in the 20th century, the Gestalt psychologists postulated the existence of mechanisms that process visual information automatically and independently of what we know, think or expect. Since then, there has always been the question as to whether these mechanisms actually exist. They do. Our work suggests that the system continuously organizes the whole scene, even though we usually are attending only to a small part of it."
Since the invention of the atomic force microscope (AFM) in 1986 by Nobel laureate Gerd Binnig, the tool has been employed to advance the science of materials in many ways, from nanopatterning (dip-pen nanolithography) to the imaging of surfaces and nano-objects such as carbon nanotubes, DNA, proteins and cells. In all these applications, the quality and integrity of the tip used to obtain the images or interrogate materials is paramount.
A common problem in atomic force microscopy is the deterioration of the tip apex as surfaces are scanned. To overcome this problem, a team of scientists from Northwestern University and Argonne National Laboratory report the microfabrication of monolithic ultra-nano-crystalline diamond (UNCD) cantilevers with tips exhibiting properties similar to single-crystal diamond.
NASA's next mission to Mars will examine the red planet in unprecedented detail from low orbit and provide more data about the intriguing planet than all previous missions combined. The Mars Reconnaissance Orbiter and its launch vehicle are scheduled to launch today, Aug. 10.
The spacecraft will examine Martian features ranging from the top of the atmosphere to underground layering. Researchers will use it to study the history and distribution of Martian water. It will also support future Mars missions by characterizing landing sites and providing a high-data-rate communications relay.
"Mars Reconnaissance Orbiter is the next step in our ambitious exploration of Mars. We expect to use this spacecraft's eyes in the sky in coming years as our primary tools to identify and evaluate the best places for future missions to land."
The spacecraft carries six instruments for probing the atmosphere, surface and subsurface to characterize the planet and how it changed over time. One of the science payload's three cameras will be the largest-diameter telescopic camera ever sent to another planet. It will reveal rocks and layers as small as the width of an office desk. Another camera will expand the present area of high-resolution coverage by a factor of 10. A third will provide global maps of Martian weather.
Researchers have discovered that tumors release fatty acids that interfere with the cells that are trying to kill them. Consequently, strategies that reduce the amount of fatty acids surrounding the tumors may give a boost to anti-cancer therapeutics.
Several forms of anti-cancer therapy rely on what is known as immunotherapeutic anti-cancer strategies, therapies that encourage the body's natural defenses, such as cytotoxic T lymphocytes, to aid in destroying tumors. However, immunotherapeutic methods are often not effective at removing established tumors for a number of reasons including a loss of the ability of the cytotoxic T lymphocytes to recognize the tumor and a physical barrier separating the lymphocytes and the tumor.
Now, researchers discovered that tumors secrete fatty acids which inhibit the cytotoxic T lymphocytes' ability to kill tumor cells.
New research into muscle contraction will give scientists a better understanding of bladder problems and pain during childbirth.
Muscles contract and relax to allow the body to perform crucial activity. Electrical signals tell the muscle when to contract, but when the muscle needs to relax, the signal is deliberately ignored. Until now scientists have been unable to understand how the body ignores this signal.
The team found that calcium, which allows muscle contraction to take place, enters the body's cells in response to electrical signals. The calcium fills up a small structure in the cell and when this is full and starts to empty, it forces the muscle to relax by preventing any more calcium entering the cell, even when it receives contraction signals.
"Electrical signals in nerves and muscles are important for all activity, from thinking to drinking. It is important for the body to be active, but it is also important for it to relax, so that it doesn't over work itself. For example, in childbirth the uterus contracts and relaxes at regular intervals to allow a baby to pass through the birth canal.
"But when we get cramps for example, our muscle is contracting too hard or too often and in the case of the ureter it would cause kidney damage. It is therefore crucial that our muscles have periods of relaxation and we have now uncovered how this occurs. This understanding should allow doctors to work more accurately with the body's natural mechanisms when treating patients."
An experiment in a dry Antarctic stream channel has shown that a carpet of freeze-dried microbes that lay dormant for two decades sprang to life one day after water was diverted into it.
"After we diverted the water into the channel, photosynthesis began the same day and the mats became abundant within a week. This showed us that they had been preserved in a cryptobiotic state."
The results showed the resilience of life in the harsh polar environment, where temperatures are below freezing for most of the year and glacial melt water flows for only five to 12 weeks annually, said Professor Diane McKnight of CU-Boulder's Institute of Arctic and Alpine Research. Such research on life in extreme environments is of high interest to astrobiologists, who consider Antarctica's McMurdo Dry Valleys an analogue for Mars because of its inhospitable climate and intermittent water flow.
"This was something we did not anticipate. These mats not only persisted for years when there was no water in the streambed, but blossomed into an entire ecosystem in about a week. All we did was add water."
Scientists have used a glowing protein from fireflies to observe the activity of a molecule that is an important target for new drugs to treat cancer, autoimmune diseases and several other disorders.
The target molecule, known as IKK (for IKappa kinase), regulates processes that can trigger dramatic changes in cellular physiology. Scientists have linked these changes to many different disorders.
"Our new system allows researchers to monitor whether drugs for these conditions are hitting this exact molecular target in cell culture and laboratory animals."
A public-private effort to develop more fuel-efficient automobiles and eventually introduce hydrogen as a transportation fuel is well-planned and identifies all major hurdles the program will face, says a new report from the National Academies' National Research Council. Many technical barriers must be overcome and new inventions will be needed, but the program, which was launched three years ago, has already made an excellent start, said the committee that wrote the report.
"The goals of this program are extremely challenging and success is uncertain, but it could have an enormous beneficial impact on energy security and the U.S. economy. Although it is still too early to speculate whether the program will achieve its long-term vision, it is making significant headway."
While the human body has plenty of specialized molecular motors and machines powering the mechanical work necessary for cells to function properly, scientists themselves face many hurdles as they try to create their own molecular machines in the laboratory.
The downsides of conventional molecular machines are that they are driven as an ensemble, by external light or chemistry, for example, and they are big -- made up of many molecules. These factors make these machines difficult to control.
In a recent paper, chemists have shown how molecular machines can be driven individually (relying on only one molecule) by applying an electric current that creates an internal energy source.
"People envision using molecular machines for computing techniques, sensors, bioengineering and solar cells, for example. Molecular machines have unique functions and properties that are different from macroscopic machines, not only and not primarily because they are of the nanoscale. Rather, they use truly molecular features such as their energy level structure, their dynamics and their response to external stimuli."
Geophysicists have had only one tool with which to peer into our planet's heart?seismology, or analysis of vibrations produced by earthquakes and sensed by thousands of instrument stations worldwide.
"How well do we know our planet? We have very few diagnostics. We only know essentially the crust of our planet. We can measure mountains. We can sample rocks on the surface of the Earth. We can drill holes a few kilometers deep and sample stuff down there, but in terms of chemical analysis or what kind of rocks there are, beyond a few kilometers, you simply don't have access."
But now, geophysicists have a new tool for studying the Earth's interior.
That tool is a gift from unlikely collaborators?physicists who study neutrinos, subatomic particles that stars spew out, and their antiparticles, called antineutrinos, which emanate from nuclear reactors and from the Earth's interior when uranium and thorium isotopes undergo a cascade of heat-generating radioactive decay processes. A detector in Japan called KamLAND (for Kamioka liquid scintillator antineutrino detector) has sensed the geologically produced antineutrinos, known as "geoneutrinos." This new window on the world that geoneutrinos open could yield important geophysical information.
In the last few years, semiconductor circuit features have shrunk to sub-100 nanometer (nm) dimensions, while the size of the thin silicon wafers that these circuits are constructed on has grown from 200 millimeters (mm) to 300 mm (about 12 inches). The payoff is a higher yield of finished devices from fewer wafers.
The tough part, however, is to make wafers substantially larger while simultaneously meeting higher quality control specifications. The optics and materials for ?printing? nanoscale circuit lines require that the wafers used are perfectly flat and of uniform thickness.
To help the semiconductor industry meet its 2010 quality control roadmap goals, researchers at the National Institute of Standards and Technology (NIST) recently developed a new instrument that accurately measures differences in thickness across a 300 mm wafer with an excellent repeatability of 5 nm.
The researchers hope the tool, with further refinements, will allow them to establish a new calibration service for ?master wafers? used in the industry to measure wafer thickness.
Meteor impacts are generally regarded as monstrous killers and one of the causes of mass extinctions throughout the history of life. But there is a chance the heavy bombardment of Earth by meteors during the planet's youth actually spurred early life on our planet.
A study of the Haughton Impact Crater on Devon Island, in the Canadian Arctic, has revealed some very life-friendly features at ground zero. These include hydrothermal systems, blasted rocks that are easier for microbes to inhabit, plus the cozy, protected basin created by the crater itself. If true, impact craters could represent some of the best sites to look for signs of past or present life on Mars and other planets.
The idea that meteor impacts could benefit or even create conditions suitable for the beginning of early life struck Canadian Space Agency geologist Gordon Osinski while he and colleagues were conducting a geological survey of the 24-kilometer (15-mile) diameter Haughton Crater. Along the rim of the crater they noticed what looked like fossilized hydrothermal pipes, a few meters in diameter.
"That set the bells ringing about possible biological implications. Hydrothermal systems are thought by many people to be the favourable places for life to evolve."
When it comes to taking the next "giant leap" in space exploration, NASA is thinking small -- really small.
"[We] try to focus on technologies that could yield useable products within a few years to a decade. For example, we're looking at how nano-materials could be used for advanced life support, DNA sequencers, ultra-powerful computers, and tiny sensors for chemicals or even sensors for cancer."
(Right: This bio-nanorobot resembles a living cell.)
In laboratories around the country, NASA is supporting the burgeoning science of nanotechnology. The basic idea is to learn to deal with matter at the atomic scale -- to be able to control individual atoms and molecules well enough to design molecule-size machines, advanced electronics and "smart" materials.
If visionaries are right, nanotechnology could lead to robots you can hold on your fingertip, self-healing spacesuits, space elevators and other fantastic devices. Some of these things may take 20+ years to fully develop; others are taking shape in the laboratory today.
Record oil prices and incentives to find alternative fuel sources are lighting a fire under research to turn biomass materials such as manure into energy.
Texas Senate Bill 20, signed this week by Gov. Rick Perry, compliments research under way to determine how and where biomass can be used. The new law requires more renewable energy to be developed and used in the next 10 years.
Combining consumer energy needs and agriculture industry trends with the legislation will push the research to become reality.
Researchers have long worked with manure as a fertilizer and have studied ways to convert it into energy, but this latest push of legislation and research should result in more energy projects becoming a reality.
Research is concentrating on finding alternative uses for the growing supplies of manure. Irrigated cropland use of manure as a fertilizer is dwindling, but the livestock industry is growing.
MARSIS, the sounding radar on board ESA?s Mars Express spacecraft, is collecting the first data about the surface and the ionosphere of Mars.
MARSIS is a very complex instrument, capable of operating at different frequency bands. Lower frequencies are best suited to probe the subsurface and the highest frequencies are used to probe shallow subsurface depths, while all frequencies are suited to study the surface and the upper atmospheric layer of Mars.
The MARSIS radar is designed to operate around the orbit ?pericentre?, when the spacecraft is closer to the planet?s surface. In each orbit, the radar has been switched on for 36 minutes around this point, dedicating the central 26 minutes to subsurface observations and the first and last five minutes of the slot to active ionosphere sounding.
The first ionospheric measurements performed by MARSIS have also revealed some interesting preliminary findings. The radar responds directly to the number of charged particles composing the ionosphere (plasma). This has shown to be higher than expected at times.
The theoretical price of having one's personal genome sequenced just fell from the prohibitive $20 million dollars to about $2.2 million, and the goal is to reduce the amount further--to about $1,000--to make individualized prevention and treatment realistic.
The sharp drop is due to a new DNA sequencing technology developed by Harvard Medical School (HMS) researchers.
The team sequenced the E. coli bacterial genome at a fraction of the cost of conventional sequencing using off-the-shelf instruments and chemical reagents. Their technology appears to be even more accurate and less costly than a commercial DNA decoding technology reported earlier this week.
The technology is based on converting a widely available and relatively inexpensive microscope with a digital camera for use in a rapid automated sequencing process that does not involve the much slower electrophoresis, a mainstay of the conventional Sanger sequencing method.
Earth?s cool, rigid upper layer, known as the lithosphere, rides on top of its warmer, more pliable neighbor, the asthenosphere, as a series of massive plates. Plates continuously shift and break, triggering earthquakes, sparking volcanic eruptions, sculpting mountains and carving trenches under the sea.
But what, exactly, divides the lithosphere and the asthenosphere? Geophysicists new research sheds new light on the nature of the boundary between these rocky regions.
Geophysicists found a sharp dividing line between the lithosphere and the asthenosphere, according to data culled from seismic sensors sprinkled across the northeastern United States and southeastern Canada. They discovered that sound waves recorded by the sensors slow considerably about 90 to 110 kilometers below ground ? a sign that the rock is getting weaker and that the lithosphere is giving way to the asthenosphere. Within in a distance of a mere 11 kilometers ? roughly 7 miles or less ? the transition is complete.
A team of neuroscientists from Penn State University report how neuron clusters in the brain overlap to communicate such combined visual information as a flower's color, shape and distance.
The team's research suggests that multitasking may be fundamental to the way the brain works.
"Since every part of the cortex has neurons that are involved in multiple tasks, there is every reason to think that this is a deep principle of brain organization."
In the visual cortex, neighboring neurons detect objects in neighboring regions of space, creating an image or map of the visual scene. Neurons are clustered according to their ability to detect different properties -- such as the vertical or horizontal edge of an object or whether the object is being seen by the left eye or the right -- but they need to overlap so each combination of features can be represented by the cortex. If the clusters did not overlap with each other the correct way, then we would have "blind spots" for certain feature combinations. For example, in certain regions of the visual scene we might detect vertical edges with only the left eye, or horizontal edges with only the right eye.
A new technique aimed at directly controlling the expression of genes by turning them on or off at the DNA level could lead to drugs for the treatment or cure of many diseases, say researchers at UT Southwestern Medical Center.
"Virtually every disease starts at the level of malfunctioning gene expression, or viral or bacterial gene expression. This is an approach that could theoretically produce a drug for the treatment or cure of almost any disease."
In two papers appearing in the online edition of the journal Nature Chemical Biology, Dr. Corey and his colleagues describe how they efficiently shut down gene expression in cultured cells by blocking the ability of chromosomal DNA to be copied into RNA and made into proteins. The studies, which Dr. Corey said represent the most significant findings thus far in his career, are the most definitive to date showing that chromosomal DNA is accessible to and can be controlled by synthetic and natural molecules.
"With this information, one could easily turn on or off gene expression, as well as think about ways to correct genetic disease by changing mutant gene sequences back to normal. Those types of things now look a lot more feasible."
NASA's Spitzer Space Telescope has found the ingredients for life all the way back to a time when the universe was a mere youngster.
"Planets and life had very early opportunities to emerge in the universe."
Using Spitzer, scientists have detected organic molecules in galaxies when our universe was one-fourth of its current age of about 14 billion years. These large molecules, known as polycyclic aromatic hydrocarbons, are comprised of carbon and hydrogen. The molecules are considered to be among the building blocks of life.
These complex molecules are very common on Earth. They form any time carbon-based materials are not burned completely. They can be found in sooty exhaust from cars and airplanes, and in charcoal broiled hamburgers and burnt toast.
The molecules, pervasive in galaxies like our own Milky Way, play a significant role in star and planet formation. Spitzer is the first telescope to see these molecules so far back in time.
"This is 10 billion years further back in time than we've seen them before."
From birth until death, our cells migrate: nerve cells make their vital connections, embryonic cells move to the proper places to form organs, immune cells zero in to destroy pathogenic organisms, and cancer cells metastasize, spreading deadly disease through the body. Scientists studying these migrations didn't know how cells determined where to go.
Until now.
A Burnham Institute study has identified a fragment of a protein that senses chemicals that induce a cell to move into the right direction. Guided by this fragment, the molecular machinery needed for cell movement begins accumulating at the leading edge, or front of a cell in response to a variety of chemical messengers, and begins the directed process of migration.
The finding is the first to determine the molecule responsible for internally choreographing directed cell migration. The experiments were conducted in several widely used laboratory models, but the molecule exists in nearly all animals, from roundworms to mammals, and likely has a conserved function throughout species. Knowing exactly what triggers cellular migration can help develop treatments that halt cancer metastasis and immune disorders like arthritis and asthma.
"Previous studies by us and others have identified how a migrating cell 'gets its wheels' and, mechanistically, is able to move. In this study, we have now determined how these wheels become pointed in the right direction. We now know this is done using a protein that holds true in most cellular systems. Seeing how this process directs cells can help us better address a host of diseases that result from too little or too much cell movement, or from cells moving in the wrong direction and to the wrong place."
Scientists from the University of North Carolina have identified a protein that may inhibit cellular movement, or migration.
The protein, CIB1, or calcium and integrin-binding protein 1, was originally discovered at UNC in 1997 as a blood platelet protein that may play a role in clotting.
Cell migration belongs to the most rudimentary of cellular functions that allow processes such as fetal development, new blood vessel formation and wound healing to occur in humans. Increased tumor cell migration also is one of the hallmarks of highly aggressive, rapidly spreading cancer tumors.
The study indicates that CIB1 inhibits cell migration by binding to and activating a protein called PAK1, or p21-activated kinase, in cancer cells. When CIB1 activates PAK1, this kinase then inhibits cell migration by adding a phosphate group to a host of other proteins in the cell.
Thus, the study suggests that CIB1 may be a likely target for new drug development aimed at decreasing tumor metastasis, or spread, throughout the body.
In illustrating the role that CIB1 plays in cell migration and PAK1 activation, the authors used a new method known as RNAi or RNA interference to knock down or reduce CIB1 expression in various cell lines. Cells with less CIB1 had less PAK1 activation and migrated faster. The authors also showed that the more CIB1 these cells had, the less likely they were to move.
The key to understanding CIB1's multifunctional role in humans is that the protein has a relative that behaves in a very similar multifunctional fashion: calmodulin. This was one of the first regulatory proteins ever discovered.
Scientists have taken a major step toward the goal of altering viruses, bacteria and tumor cells so that they demand attention from immune cells designed to destroy them. According to researchers at the University of Rochester Medical Center, they have determined for the first time a single biochemical feature of disease-causing molecules (pathogens) that, if changed, would force them to provoke an attack by the human immune system.
Recognizing molecules as "self," versus foreign invaders to be destroyed, is a central responsibility of the immune system. Tumors closely resemble self or "host" tissues and can confuse the system. Viruses and bacteria are immediately recognizable as foreign, but have learned to change shape so often that the system loses track of them. Pathogens use the same tricks to escape the immunity provided by vaccines.
In an effort to deny diseases the ability to hide, researchers have for years been asking a key question: Why do our bodies select certain, small pieces (epitopes) of each disease-causing molecule to trigger an immune response, while ignoring the rest?
Those few, triggering protein fragments are termed "immunodominant." Unfortunately, the immune system sometimes makes poor choices about which epitopes to pay attention to, and which to ignore. Understanding of how immunodominance is conferred would enable vaccine designers to shift the immune system spotlight to parts of pathogens that they cannot change in efforts to escape detection. For example, a vaccine could be designed to target a protein fragment central to a virus?s ability to reproduce, or to invade its prey.
"Our study identified for the first time the chemical mechanism that determines immunodominance, and proved that it can be fine-tuned. If confirmed, the findings could launch a new wing of research seeking to re-engineer viruses, bacteria and tumor cells to make them hundreds of times more likely to be noticed and destroyed by our immune system."
"If confirmed, this discovery will bring immundominance and a major portion of the immune system under our control for the first time."
A new sensor being patented by Ohio State University could be used to detect concealed weapons or help pilots see better through rain and fog.
Unlike X-ray machines or radar instruments, the sensor doesn't have to generate a signal to detect objects ? it spots them based on how brightly they reflect the natural radiation that is all around us every day.
Developers likened this reflection to the way glossy and satin-finish paints reflect light differently to the eye.
Once the sensor is further developed, it could be used to scan people or luggage without subjecting them to X-rays or other radiation. And if the sensor were embedded in an airplane nose, it might help pilots see a runway during bad weather.
The Ohio State sensor isn't the only ambient radiation sensor under development, but it is the only that is compatible with silicon ? a feature that makes it relatively inexpensive and easy to work with.
The new sensor grew out of his team's recent invention of a device called a tunnel diode that transmits large amounts of electricity through silicon.
Diodes are one-way conductors that typically power amplifiers for devices such as stereo speakers. This particular diode is unique because it is compatible with mainstream silicon, so computer chip makers could manufacture it cheaply and integrate it with existing technology easily.
By firing rapid pulses of polarized light at corn, spinach and other crops, researchers have uncovered a picture of plant health that is invisible to the naked eye. Using a portable light source and detector technology, the researchers can differentiate minute differences in leaf colors - indicators of over- or under-fertilization, crop-nutrient levels and perhaps even disease.
The researchers hope their tractor-mountable N-Checker (for "nitrogen-checker") apparatus will help farmers determine in real time how much fertilizer to apply. By preventing waste, the system could decrease the cost of crop production and dramatically cut the nitrogen-laden runoff responsible for algal blooms and other damage to wetlands and waterways.
"With our technology, we are able to easily see what is hidden from conventional instruments. The system eliminates interference from light reflected at a leaf's surface and allows us to see light re-emitting from within."
Depending on the plant, leaves reflect, transmit and absorb varying amounts of light. Polarized light that enters a leaf's interior can lose its polarity and be re-emitted as "depolarized" light. The depolarized light reveals nitrogen content and other properties the proprietary sensors in the N-Checker can detect.
Changes in nitrogen levels change the way light interacts with the molecules in the leaf, characteristically affecting the spectrum of light that re-emits from the plant. Chlorophyll molecules, in particular, contain nitrogen atoms that play a critical role in photosynthesis.
The researchers have experimented with two versions of their apparatus. The original version channels broad-spectrum light from a xenon flashlamp through a series of calcite crystals to illuminate each corn, sugar beet, cotton or other broad-leaf crop with a tiny, transient spot of polarized light. Moving from leaf to leaf, that system can measure nitrogen levels in 60 plants per minute.
Instead of a broad-spectrum lamp as its source, the N-Checker uses two red-light sources that cut down on sensor and polarizer costs and increase the system speed. The red region of the electromagnetic spectrum is important because it reveals not just total chlorophyll content, but also relative amounts of the various types of chlorophyll molecules.
"Other devices use both red and infrared wavelengths. Those devices tend to be imprecise because they measure bulk chlorophyll content, which can result from a number of factors."
By using two specific, visible, red wavelengths, the N-Checker can differentiate among the several types of chlorophyll molecules and therefore reveal nitrogen-dependent plant health information.
The N-Checker can take 1000 measurements per second--at least every 10th of an inch--while moving at roughly 5 miles an hour. At that speed, a farmer could survey and fertilize tens of acres in a day, or hundreds of acres per day with a multi-sensor system.
Using high-speed collisions between gold atoms, scientists think they have re-created one of the most mysterious forms of matter in the universe -- quark-gluon plasma. This form of matter was present during the first microsecond of the Big Bang and may still exist at the cores of dense, distant stars.
"We have been trying to melt neutrons and protons, the building blocks of atomic nuclei, into their constituent quarks and gluons. We needed a lot of heat, pressure and energy, all localized in a small space."
The scientists produced the right conditions with head-on collisions between the nuclei of gold atoms. The resulting quark-gluon plasma lasted an extremely short time -- less than 10-20 seconds, Cebra said. But the collision left tracings that the scientists could measure.
"Our work is like accident reconstruction. We see fragments coming out of a collision, and we construct that information back to very small points."
Quark-gluon plasma was expected to behave like a gas, but the data shows a more liquid-like substance. The plasma is less compressible than expected, which means that it may be able to support the cores of very dense stars.
"If a neutron star gets large and dense enough, it may go through a quark phase, or it may just collapse into a black hole. To support a quark star, the quark-gluon plasma would need rigidity. We now expect there to be quark stars, but they will be hard to study. If they exist, they're semi-infinitely far away."
How long does it take an electron to travel from an atom to the next atom?
The main conclusion is that the time required is much shorter than the time it could be measured until now. This study analyses the dynamics of electrons in the case of sulphur atoms laid on metal surfaces (ruthenium). Electrons jump from the sulphur to the metallic surface in 320 attoseconds approximately (1 attosecond is equivalent to 0.000000000000000001 seconds).
In order to have an idea how small this number is, we could say that one attosecond at one second would be what a second would be at the age of the universe (about 14,000 millions of years).
The main innovation of this work consists on the possibility to measure a charge transference time between an atom and a surface at attoseconds, and at the same time, two theory physicists of the University of the Basque Country (EHU) have worked out details of the process by means of quantum mechanics.
This phenomenon is one of the fastest ever seen directly in the solid state physics, and it shows it is possible to obtain information about the dynamics of electrons with great resolution. In order to achieve such resolution it is necessary to use a precise measurement "device", in this case, a clock that provides electronic transitions within the same atom.
The question about the time electrons require to travel between different atomic centres is very important for several phenomena. It is important to optimise the design of materials that will constitute future electronic devices (areas of nanoelectronic and molecular electronic). Particularly, the technique used allows to distinguish among different values of the electronic "spin" (giromagnetic ratio), and this opens new areas of study in the field of "spintronic", a new electronics in which the key factor is not the electron charge as in the conventional electronics, but the spin. Charge transference processes are also essential for life (photosynthesis), energy production (photovoltaic cells) and, in general, for the photochemistry and electrochemistry.