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ScienceDaily (Jan. 7, 2011) - Certain molecules do exist in two forms which are symmetrical mirror images of each other: they are known as chiral molecules. On Earth, the chiral molecules of life, especially amino acids and sugars, exist in only one form, either left-handed or right-handed. Why is it that life has initially chosen one form over the other?

Because the size of these metallic hotspots is far smaller than the wavelength of incident light, a new technique was needed to map the electromagnetic field within a hotspot. The Berkeley researchers developed the BEAST method to capitalize on the fact that individual fluorescent dye molecules can be localized with single nanometer accuracy. The fluorescence intensity of individual molecules adsorbed on the surface provides a direct measure of the electromagnetic field inside a single hotspot. BEAST utilizes the Brownian motion of single dye molecules in a solution to make the dyes scan the inside of single hotspot stochastically, one molecule at a time.

"The results are published in Nature Medicine today. Co-author Stanley Hazen, head of cardiovascular medicine at the Cleveland Clinic in Ohio, says that the study could signal a new approach to diet and health. In some cases, an individual's collection of intestinal microbes may be as important to their diet as anything on a nutrition label, he says. "Bacteria make a whole slew of molecules from food," he says, "and those molecules can have a huge effect on our metabolic processes.""

For many years researchers have been attempting to understand how human memory works. Precisely how it works. Down to the specific molecules in play. That's what I call attention to detail. The researchers involved in a recent study at Brandeis University have, for the first time, identified the specific molecule involved in memory storage in the brain.

A new eco-friendly coating is made by binding a water-loving molecule to a Teflon-like molecule that repels oil. This pairing makes for a surface that prevents oil from sticking to it, while also allowing it to be wet by water.

ScienceDaily (June 4, 2011) - Do the principles of quantum mechanics apply to biological systems? Until now, says Prof. Ron Naaman of the Institute's Chemical Physics Department (Faculty of Chemistry), both biologists and physicists have considered quantum systems and biological molecules to be like apples and oranges. But research he conducted together with scientists in Germany, which appeared recently in Science, shows that a biological molecule -- DNA -- can discern between quantum states known as spin.

Difference between vapor and gas The term gas refers to a substance that is in its gaseous form or a substance that has a single defined thermodynamic state at room temperature whereas a vapor refers to a substance that is a equilibrium between two phases at room temperature, namely gaseous and liquid phase. All matter on earth exists in any of the three states: solid, liquid or gaseous. 'Gas' refers to a substance in the gaseous state. Gases do not have either shape or volume. However, the term 'vapor' or 'vapour' refers to a substance in equilibrium between two phases, usually liquid and gaseous. Vapor is not a state of matter but is a specific type of gas. Gases are in a gaseous state at room temperature. The molecules in a gas can expand to occupy any available volume as there is very little inter molecular attraction. On the other hand, the molecules of a vapor gain energy and vaporize from a substance which is either a solid or liquid at room temperature. For example, steam is a water vapor that turns into water at room temperature. Oxygen, which is a gas, will still be a gas at room temperature. Gas is a state of matter. Vapor is not, it is constantly in transition. An easy way to distinguish between vapor and gas is that vapor is something that can be seen or smelled or something that settles down on the ground, while one cannot see a gas but can only smell it. However, there are some exceptions to this classification, for example, water vapor. Water vapor cannot be smelt and it does not settle down on the ground.

quantum

"The same technology could potentially be used for bladder and multiple myeloma cancers, which also shed identifiable markers in urine. "Our goal is a device the size of a home pregnancy test priced around $10. Other prostate cancer tests coming to market cost up to $4,000 each. The UC Irvine team made price a key design factor of their work..The UC Irvine team developed a new type of sensor: They added nanoscale protein receptors to tiny, pencil-like viruses called phages that live only within bacteria. Double wrapping the phages with additional receptors greatly increases the capture and transmission of cancer molecule signals."

"We provide novel evidence for the effects of metabolic dysfunctions on brain function using the rat model of metabolic syndrome induced by high fructose intake. * We describe that the deleterious consequences of unhealthy dietary habits can be partially counteracted by dietary supplementation of n-3 fatty acid. * High sugar consumption impaired cognitive abilities and disrupted insulin signalling by engaging molecules associated with energy metabolism and synaptic plasticity; in turn, the presence of docosahexaenoic acid, an n-3 fatty acid, restored metabolic homeostasis. * These findings expand the concept of metabolic syndrome affecting the brain and provide the mechanistic evidence of how dietary habits can interact to regulate brain functions, which can further alter lifelong susceptibility to the metabolic disorders. "

"explains how nitric oxide, a signaling molecule involved in the immune system, leads to biofilm formation. "It is estimated that about 80 percent of human pathogens form biofilms during some part of their life cycle," said Scripps Research president and CEO Michael Marletta, PhD, who led the work."

""We probably have underestimated the role our microbial flora play in modulating disease risk," says Daniel Rader, a heart disease specialist at the University of Pennsylvania School of Medicine. Rader, who was not involved in the study, says that gut bacteria may not be as big a factor in causing heart disease as diabetes or smoking, but could be important in tipping some people toward sickness. Researchers led by Stanley Hazen, a cardiologist at the Cleveland Clinic, didn't start out to study gut bacteria. In fact, says Hazen, he had "no clue - zero," that intestinal microbes were involved in heart disease. "I'd never even considered it or thought of the concept." Hazen and his colleagues compared blood plasma from healthy people to plasma from people who had had heart attacks, strokes or died to see if substances in the blood could predict who is in danger from heart disease. The researchers found 18 small molecules associated with fat buildup in the arteries. One of the best predictors turned out to be a byproduct made when gut bacteria break down a fat called choline (also known as lecithin). The more of this byproduct, called trimethylamine N-oxide or TMAO, a person or mouse has in the blood, the higher the risk of getting heart disease, the researchers found. Gut bacteria are actually middlemen in TMAO production. The microbes convert lecithin to a gas that smells like rotten fish. Then an enzyme in the liver changes the foul-smelling gas to TMAO."

"The molecule PKR (the double-stranded RNA-activated protein kinase) was originally described as a sensor of viral infections, but its function in the brain was totally unknown," said Dr. Mauro Costa-Mattioli, assistant professor of neuroscience at BCM and senior author of the paper. Since the activity of PKR is altered in a variety of cognitive disorders, Costa-Mattioli and colleagues decided to take a closer look at its role in the mammalian brain. Super memory The authors discovered that mice lacking PKR in the brain have a kind of "super" memory. "

By working with the simplest amino acids and elementary RNAs, physicists led by Rockefeller University's Albert J. Libchaber, head of the Laboratory of Experimental Condensed Matter Physics, have now generated the first theoretical model that shows how a coded genetic system can emerge from an ancestral broth of simple molecules.

By working with the simplest amino acids and elementary RNAs, physicists led by Rockefeller University's Albert J. Libchaber, head of the Laboratory of Experimental Condensed Matter Physics, have now generated the first theoretical model that shows how a coded genetic system can emerge from an ancestral broth of simple molecules.

MIT scientists have discovered that endothelial cells, which line the blood vessels, secrete molecules that suppress tumor growth and keep cancer cells from invading other tissues, a finding that could lead to a new way to treat cancer.

Life must have begun with a simple molecule that could reproduce itself - and now we think we know how to make one

Until recently, the control of protein synthesis seemed straightforward and of little concern to most neuroscientists. However, the simple story of gene transcription into messenger RNA (mRNA) and subsequent translation into a protein has recently become considerably more complicated. Small RNA molecules have been discovered that can determine when and if the mRNA for a particular protein will be translated.

Red-eye flights, all-night study sessions, and extra-inning playoff games all deprive us of sleep and can leave us forgetful the next day. Now scientists have discovered that lost sleep disrupts a specific molecule in the brain's memory circuitry, possibly leading to treatments for tired brains.