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Growing environmental problems resulting from farming argue for a shift toward practices that use lower inputs of pesticides and energy and more recycling of energy and materials, according to an article published in the May 2007 issue of BioScience. The author, Craig J. Pearson of the University of Guelph, documents how semiclosed agricultural systems -- which he terms "regenerative" -- could enhance global sustainability of biological resources, curtail greenhouse gas emissions and groundwater contamination, and reduce farming's reliance on oil imports and water.
In a breakthrough that could make the production of cellulosic ethanol less expensive, Cornell researchers have discovered a class of plant enzymes that potentially could allow plant materials used to make ethanol to be broken down more efficiently than is possible using current technologies.
There is a growing recognition that corn ethanol is unlikely to provide a long-term solution, or one that is environmentally sustainable, and so scientists are turning to cellulose as an alternative.
Production of ethanol from cellulose in mass quantities that are priced competitively with corn-based ethanol has not yet been possible. And without the cellulosic ethanol, the national goal for ethanol production to reduce oil imports will be impossible to reach, experts say.
Materials scientists will tell you that to best understand, characterize and eventually utilize the properties of a specific material, you have to be able to define how the atoms within it are arranged. In the case of common crystals, there are numerous methods, such as X-ray diffraction, by which this can be done. Not so for nanostructured materials (structures with atomic arrangements at a scale of 1-100 nanometers, or between 5 to 1,000 atoms in size) where the inability to determine atomic order with high precision has been dubbed the “nanostructure problem.”
With gold nanoparticles, DNA and some smart chemistry as their tools, scientists at Northwestern University have developed a simple "litmus test" for mercury that eventually could be used for on-the-spot environmental monitoring of bodies of water, such as rivers, streams, lakes and oceans, to evaluate their safety as food and drinking water sources.
An article detailing the colorimetric screening technology and its success detecting mercury will be published online April 27 by Angewandte Chemie, the prestigious European journal of applied chemistry.
Researchers at the National Institute of Standards and Technology (NIST) have devised a system for manipulating and precisely positioning individual nanowires on semiconductor wafers. Their technique, described in a recent paper, allows them to fabricate sophisticated test structures to explore the properties of nanowires, using only optical microscopy and conventional photolithographic processing in lieu of advanced (and expensive) tools such as focused ion or electron beams.
The mouth is a tough environment—which is why dentists do not give lifetime guarantees. Despite their best efforts, a filling may eventually crack under the stress of biting, chewing and teeth grinding, or secondary decay may develop where the filling binds to the tooth. Fully 70 percent of all dental procedures involve replacements to existing repairs, at a cost of $5 billion per year in the United States alone.
A huge number of diagnostic techniques are based on PCR (the polymerase chain reaction): the use of PCR allows even the tiniest amounts of genetic material to be duplicated so that it can be analyzed. This should make things such as the rapid and reliable identification of a dangerous infectious agent possible.
Researchers at Texas University have now developed a prototype of a battery-driven pocket PCR device, which they have now introduced in the journal Angewandte Chemie. Simple in its construction and handling, this unconventional thermocycler can be produced for about ten US dollars—ideal for applications in areas lacking infrastructure.
As products made with nanometer-scale materials and devices spread to more industries and markets, there is a growing opportunity and responsibility to leverage nanotechnology to reduce pollution, conserve resources and, ultimately, build a "clean" economy, advises a new report from the Project on Emerging Nanotechnologies.
A major study has shed new light on the dim layer of the ocean called the "twilight zone"—where mysterious processes affect the ocean's ability to absorb and store carbon dioxide accumulating in our atmosphere.
The results of two international research expeditions to the Pacific Ocean, published April 27 in the journal Science, show that carbon dioxide —taken up by photosynthesizing marine plants in the sunlit ocean surface layer—does not necessarily sink to the depths, where it is stored and prevented from re-entering the atmosphere as a greenhouse gas. Instead, carbon transported to the depths on sinking marine particles is often consumed by animals and bacteria and recycled in the twilight zone—100 to 1,000 meters below the surface—and never reaches the deep ocean.
An international team led by the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., has developed a prototype of the first fully integrated prosthetic arm that can be controlled naturally, provide sensory feedback and allows for eight degrees of freedom—a level of control far beyond the current state of the art for prosthetic limbs. Proto 1, developed for the Defense Advanced Research Projects Agency (DARPA) Revolutionizing Prosthetics Program, is a complete limb system that also includes a virtual environment used for patient training, clinical configuration, and to record limb movements and control signals during clinical investigations.
Scientists at the Schepens Eye Research Institute, an affiliate of Harvard Medical School, have identified a key mechanism for successfully transplanting tissue into the adult central nervous system. The study found that a molecule known as MMP-2 (which is induced by stem cells) has the ability to break down barriers on the outer surface of a damaged retina and allow healthy donor cells to integrate and wire themselves into remaining recipient tissue. The finding, reported in the current issue (April 25, 2007) of the Journal of Neuroscience, holds great promise not only for patients with retinal disease, but for those suffering from spinal cord injuries and neurodegenerative disorders such as Parkinson’s and Alzheimer’s Diseases.
Earth sits between two worlds that have been devastated by climate catastrophes. In the effort to combat global warming, our neighbours can provide valuable insights into the way climate catastrophes affect planets.
Modelling Earth’s climate to predict its future has assumed tremendous importance in the light of mankind’s influence on the atmosphere. The climate of our two neighbours is in stark contrast to that of our home planet, making data from ESA’s Venus Express and Mars Express invaluable to climate scientists.
Terahertz (THz) radiation, or far-infrared light, is potentially very useful for security applications, as it can penetrate clothing and other materials to provide images of concealed weapons, drugs, or other objects. However, THz scanners must usually be very close to the objects they are imaging. Doubts have lingered over whether it is possible to use THz waves to image objects that are far away, because water vapor in air absorbs THz radiation so strongly that most of it never reaches the object to be imaged.
Tiny pores within plant cells may hold promise for green fuels.
Researchers have discovered that particles from cornstalks undergo previously unknown structural changes when processed to produce ethanol, an insight they said will help establish a viable method for large-scale production of ethanol from plant matter.
Their research demonstrates that pretreating corn plant tissue with hot water - an accepted practice that increases ethanol yields 3 to 4 times - works by exposing minute pores of the plant's cell walls, thus increasing surface area for additional reactions that help break down the cell wall.
Carnegie Mellon University researchers have developed a new series of robots that are simple enough for almost anyone to build with off-the-shelf parts, but are sophisticated machines that wirelessly connect to the Internet.
The robots can take many forms, from a three-wheeled model with a mounted camera to a flower loaded with infrared sensors. They can be easily customized and their ability to wirelessly link to the Internet allows users to control and monitor their robots’ actions from any Internet-connected computer in the world.
An electrical circuit that should carry enough power to produce the long-sought goal of controlled high-yield nuclear fusion and, equally important, do it every 10 seconds, has undergone extensive preliminary experiments and computer simulations at Sandia National Laboratories’ Z machine facility.
Z, when it fires, is already the largest producer of X-rays on Earth and has been used to produce fusion neutrons. But rapid bursts are necessary for future generating plants to produce electrical power from sea water. This had not been thought achievable till now.
Global Research Technologies, LLC (GRT), a technology research and development company, and Klaus Lackner from Columbia University have achieved the successful demonstration of a bold new technology to capture carbon from the air. The "air extraction" prototype has successfully demonstrated that indeed carbon dioxide (CO2) can be captured from the atmosphere. This is GRT’s first step toward a commercially viable air capture device.
A Georgia Tech research team has discovered that water exhibits very different properties when it is confined to channels less than two nanometers wide – behaving much like a viscous fluid with a viscosity approaching that of molasses. Determining the properties of water on the nanoscale may prove important for biological and pharmaceutical research as well as nanotechnology. The research appears in the March 15 issue of the journal Physical Review B.
Cell membranes are like two-dimensional fluids whose molecules are distributed evenly through lateral diffusion. But many important cellular processes depend on cortical polarity, the locally elevated concentration of specific membrane proteins. Roland Wedlich-Soldner at the Max Planck Institute of Biochemistry in Martinsried, Germany, and his colleagues at Harvard Medical School, Boston, The Stowers Institute for Medical Research, Kansas City, and the University of Texas Southwestern Medical Center, Dallas, have analysed and quantified how cortical polarity develops and how an asymmetric distribution of molecules can be dynamically maintained. In their study they combined experiments on living cells with a mathematical model to show among other things that polarised regions in membranes are defined with nearly optimal precision. This novel approach is an important step towards a spatially and temporally quantifiable model of the cell.