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Cause of Ischemic Stroke Analyzed
Scientists studied clots removed from the brain blood vessels of 25 stroke victims. The clots were retrieved during therapy using a novel mechanical clot-retrieval device called the MERCI (Mechanical Embolus Removal in Cerebral Ischemia) Retriever. The removed clots were analyzed under the microscope to compare their component structures. "Unexpectedly, no two retrieved clots looked the same, even though all were constructed from the same basic components of fibrin, white cells and red blood cells," said lead author Dr. Victor Marder, professor of hematology and oncology at the David Geffen School of Medicine at UCLA and a UCLA Stroke Center member. "The same components were involved in both the newly formed and mature, enlarging clots. Red blood-cell accumulations had previously been considered to dominate the structure of clots that formed within a heart chamber, but our results suggest that red cells often accumulated on clots after impaction in the brain artery". The findings could lead to better therapies to prevent clots, clear blockages and reverse strokes in the crucial first hours after they occur......... Posted by: Sean Permalink Source Web Database For Ionic Liquid Data
There has been an explosion of interest in the last few years (including a near-exponential growth in journal articles) in the synthesis and use of ionic liquids--salts that melt below the boiling point of water. A large part of the interest is due to something ionic liquids don't have: a measurable vapor pressure at room temperature. With typical vapor pressures in the range of 10-10 pascal (10-14 psi), ionic liquids have essentially no vapor emissions and so look like excellent candidates for "green solvents" to replace hazardous, air-polluting organic solvents like acetone and benzene. With dozens of anions and cations to choose from, they can be tailored to specific needs and may be especially useful as solvents for biocatalysis. One problem has been a lack of organized, reliable data on the basic physical properties of ionic liquids, critical information for designing industrial processes. NIST, in cooperation with the International Union of Pure & Applied Chemistry (IUPAC), has created ILThermo, the IUPAC Ionic Liquids Database. Launched at the end of July, ILThermo is a free, web-based research tool that allows users worldwide to access an up-to-date data collection of thermodynamic, thermochemical and transport properties of pure ionic liquids as well as binary and ternary mixtures......... Posted by: Sarah Permalink Source Advanced Imaging Facility And Hydrogen Fuel Cells
With visualization powers 10 times better than those achieved previously, scientists can "see" water production and removal in fuel cells under a range of simulated operating conditions, from arctic cold to desert heat. "This as-it-happens, inside view is essential because fuel-cell performance depends on a delicate balance," explains NIST physicist Muhammad Arif, who leads the NIST team that developed the instrument. "Too little--or too much--water can shut it down. "Better water management is fundamental to meeting targets for fuel cell performance, reliability and durability. Reaching these targets, in turn, is integral to efforts to replace petroleum with hydrogen to power cars and trucks by 2020--the goal of President Bush's Hydrogen Fuel Initiative. In fuel cells, which actually are stacks of battery-like devices, water is the by-product of the chemical process that uses electrons stripped from hydrogen molecules to generate electricity. With the newly commissioned Neutron Imaging Facility, water quantities smaller than 1 microgram (millionth of a gram) are revealed, and details as small as 0.02 millimeter can be discerned in images. Even better spatial resolution is expected......... Posted by: Kevin Permalink Source Bacteria Can Help Predict Ocean Change
Scientists have long endorsed the concept of a unique biological niche for most animals and plants a shark, for example, has a different role than a dolphin. Bacteria instead have been relegated to an also-ran world of "functional redundancy" in which few species are considered unique, said Jed Fuhrman, holder of the McCulloch-Crosby Chair in Marine Biology in the USC College of Letters, Arts and Sciences. In The Proceedings of the National Academy of Sciences' Early Edition, Fuhrman and colleagues from USC and Columbia University show that most kinds of bacteria are not interchangeable and that each thrives under predictable conditions and at predictable times. Conversely, the kinds and numbers of bacteria in a sample can show where and when it was taken. "I could tell you what month it is if you just got me a sample of water from out there," Fuhrman said. The researchers took monthly bacteria samples for more than four years in the Pacific Ocean near the USC Wrigley Institute's marine laboratory on Catalina Island. They used statistical methods to correlate the bacteria counts with the Wrigley Institute's monthly measurements of water temperature, salinity, nutrient content, plant matter and other variables......... Posted by: Tyler Permalink Source Surprising Telescope Observations
CU-Boulder astrophysicist Jeffrey Linsky said new data gathered by NASA's Far Ultraviolet Spectroscopic Explorer, or FUSE, satellite, shows why deuterium appears to be distributed unevenly in the Milky Way Galaxy. It apparently has been binding to interstellar dust grains, changing from an easily detectable gaseous form to an unobservable solid form, said Linsky, a fellow of JILA, a joint institute of CU-Boulder and the National Institute of Standards and Technology. The FUSE deuterium study, six years in the making, solves a 35-year-old mystery concerning the distribution of deuterium in the Milky Way while posing new questions about how stars and galaxies are made, according to the research team. A paper on the subject by a team of international researchers led by Linsky is being published in the Aug. 20 issue of The Astrophysical Journal. "Since the 1970s, we have been unable to explain why deuterium levels vary all over the place," said Linsky. "The answer we found is as unsettling as it is exciting"......... Posted by: Brooke Permalink Source Hidden Milky Way deuterium found
This form of hydrogen, called deuterium, was created a few minutes after the Big. Bang, but has been slowly destroyed as it is burned in stars and converted to heavier elements. In fact, it now turns out, that destruction has been occurring even more slowly than previously thought. Published in the Aug. 20 issue of the Astrophysical Journal, the FUSE team's new large deuterium survey solves a 35-year-old mystery concerning deuterium's uneven distribution in the Milky Way galaxy even as it poses new questions about how stars and galaxies are made. "For more than three decades, we have struggled to understand and explain the widely varying levels of deuterium," said Warren Moos, principal investigator of NASA's. FUSE mission and a professor in the Henry A. Rowland Department of Physics and Astronomy at the Krieger School of Arts and Sciences at Johns Hopkins. "Though the answer we have found may be unsettling to some, it represents a major step forward in our understanding of chemical evolution"......... Posted by: Brooke Permalink Source Flatworms And Regeneration Research
Planaria have been studied for hundreds of years, but modern genomic techniques have given scientists new ways to delve into the molecular biology underlying planarian regeneration.Accordingly, Phillip Newmark and his colleagues at the University of Illinois at Urbana-Champaign (UIUC) used a technique called "RNA interference" to stop a particular gene from producing its encoded protein.Without the protein, the planaria's stem cell population died out, and they lost the ability to regenerate.Now researchers will see if the gene plays a similar role in stem cells from other organisms. All animals contain stem cells, which are unique because they have no specialized function but can mature into almost any cell type and do almost any job the body requires. In planaria, stem cells are responsible for the animal's ability to regenerate its entire body, even from small very small bits. Planaria are popular for introductory biology experiments because if one is chopped in half, two grow back.In fact, only 1/279th of a planarian is needed to regenerate a complete worm......... Posted by: Ashley Permalink Source Innovative Generator For Energy Savings
MIT alumnus Eric Guyer, CEO of Climate Energy, describes his company's micro-combined heat and power unit at an MIT Energy Club event. Photo / Dan Bersak
Guyer described Climate Energy's micro-combined heat and power unit (micro-CHP) to the standing-room-only crowd gathered in the Tang Center as "hopefully, the next big thing in energy". Guyer's talk was part of the Energy Club's lecture and discussion series, sponsored by the Graduate Student Council. These biweekly events occur year-round and feature lecturers or student-led discussions on important energy topics. The idea for combined heat and power (CHP) is nothing new, Guyer said. "Thomas Edison's first power plant was combined," he explained. Still, the idea of generating both heat and energy in a way that is not only affordable but also quiet enough for use in a private home is a more recent development. "On an industrial scale, CHP is used all the time," Guyer said. A natural gas-powered micro-CHP unit has the potential to save the consumer money by using the same fuel they buy anyway to generate both heat and electricity with greater efficiency. The micro-CHP systems are driven by heat-demand, delivering electricity as the byproduct. "This is all about providing thermal comfort to homeowners," Guyer said......... Posted by: Kevin Permalink Source Microbe center plumbs depths of ocean life
The Center for Microbial Oceanography: Research and Education (C-MORE) will facilitate collaborations among the previously separate disciplines of oceanography, microbiology, ecology and genomics. These new alliances will enable a deeper understanding of the seas, including their potential response to global environmental variability and climate change. C-MORE, which will receive approximately $19 million from the National Science Foundation over the first five years, is based at the University of Hawaii at Manoa. Participating institutions in addition to MIT and UH Manoa are the Woods Hole Oceanographic Institution, Oregon State University, the Monterey Bay Aquarium Research Institute, the University of California at Santa Cruz, and the Hawaii Department of Education. "A central objective of C-MORE will be to increase understanding about how biological diversity detected at the genome level expresses itself at the ecosystem function level, and then to transfer this knowledge to policymakers to assist them in their decision-making process," said MIT Professor Edward DeLong, C-MORE associate director for research. "Marine microorganisms are invisible to the naked eye, but their presence enables all multicellular life to exist, including human populations," said DeLong, who holds appointments in the Department of Civil and Environmental Engineering (CEE) and the Biological Engineering Division. "Novel methods in molecular biology combined with satellite- and sea-based remote sensing technologies provide an unprecedented opportunity to study microorganisms across broad spatial scales ranging from genes to entire ocean basins"......... Posted by: Tyler Permalink Source Life and death in the hippocampus
According to a research findings published in a forthcoming issue of Nature, researchers in the lab of Fred H. Gage, Ph.D., a professor in the Gene Expression Laboratory and the Vi and John Adler Chair for Research on Age-Related Neurodegenerative Diseases, identify a subunit of the NMDA receptor, a protein complex that transduces signals sent by neighboring cells, as the cells' life-saving equipment that allows them to integrate into the existing brain circuitry. The NMDA receptor is activated by the neurotransmitter glutamate, a chemical released by neurons in order to transmit information to neighboring cells. Whenever the receptor picks up a glutamate signal it is stimulated and relays the signal. But for newborn neurons that signal means something else entirely -- survival. "When we removed the NMDA receptor, that is when cells make connections in response to glutamate in the environment, the newborn neurons withered and died at a specific stage of their maturation," explains Gage. " The NMDA receptor modulates synapse formation and determines what pattern of input activity new neurons receive, which in turn determines survival or death"......... Posted by: Sean Permalink Source |
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