August 27, 2006, 8:58 PM CT

Bees Calculation Sets Industry Buzzing

An ingenious new mathematical procedure based on the behaviour of honey bees is delivering sweet results for industry.

Scientists at Cardiff University's Manufacturing Engineering Centre (MEC) developed the procedure, or algorithm, after observing the "waggle dance" of bees foraging for nectar. The algorithm enables companies to maximise results by changing basic elements of their processes.

When a bee finds a source of nectar, it returns to the hive and performs a dance to show other bees the direction and distance of the flower patch and how plentiful it is. The other workers then decide how a number of of them will fly off to find the new source, depending on its distance and quality.

The MEC team's Bees Algorithm mimics this behaviour. A computer can be set up to calculate the results of different settings on a manufacturing process. More computing power is then devoted to searching around the most successful settings, in the same way as more bees are sent to the most promising flower patches.

The Algorithm has been shown to cope with up to 3,000 variables and is faster than existing calculations. By entering basic data about all or part of a company, or even just one machine, the MEC team can calculate the best outcome for a wide range of business processes. They have already used the Bees Algorithm to work out the most efficient settings on welding systems and for the design of springs.........

Posted by: Ashley      Permalink         Source

August 24, 2006, 9:53 PM CT

Chemical Compounds Restore Normal Glucose Levels

Treatment of obese and diabetic mice with compounds that act as chemical chaperones called PBA and TUDCA restored healthy glucose levels and normal insulin action - and reduced the presence of fatty liver disease - as per a research studyreported in the August 25 issue of Science. The work was conducted by a team of scientists from the Harvard School of Public Health (HSPH).

Type 2 diabetes - 90 to 95 percent of all diabetes cases - affects an estimated 18 million people in the United States, and causes some 200,000 deaths a year. Obesity is closely linked to insulin resistance and is one of the leading risk factors for type 2 diabetes. The molecular mechanisms that link these two metabolic diseases remain under investigation, and current therapeutic options are limited.

Gokhan S. Hotamisligil, chair of the HSPH Department of Genetics and Complex Diseases, is the senior author of the Science paper. In 2004, he led a team that identified a major molecular pathway that causes diabetes. A cornerstone of that discovery was a hypothesis that the key to the obesity-diabetes connection might be found in the endoplasmic reticulum, or ER - a system of folded membranes and tubules in the cytoplasm of cells where proteins and lipids are manufactured, processed, and shipped around the cell. When unusual demands - such as excess fat - are put on the ER's capacity, the organelle starts failing, and the cell enters an emergency mode, emitting stress signals. The condition is called ER stress. Cellular inflammation, insulin resistance and diabetes result. (http://www.hsph.harvard.edu/press/releases/press10142004.htm).........

Posted by: Sarah      Permalink         Source

August 23, 2006, 6:10 PM CT

Antarctic Ozone Hole

Twenty years ago this month, government and university researchers ventured to Antarctica to study the cause of a hole in the stratospheric ozone layer over the southernmost continent. Those observations were the first definitive demonstration that humans are capable of affecting the entire global climate system and led to the Montreal Protocol, the first treaty to address the Earth's environment.

Today, Susan Solomon and David Hoffman, who led the research team, met with colleagues from the National Oceanic and Atmospheric Administration (NOAA) and the National Science Foundation (NSF) at a news briefing in Washington, D.C., to reflect on the importance of the finding and discuss its implications for the future.

"The patient hasn't recovered," said Hoffman, who heads NOAA's global atmospheric monitoring program. "But it's not getting any sicker. We really have not seen any recovery in Antarctica," he said.

Hoffman also predicted it would take until 2060 for the ozone layer to heal completely, provided humans stop all release of man-made substances containing chlorine or bromine.

Their work began in 1986, when NSF, NOAA and NASA rapidly put together a research team, known as the National Ozone Expedition, or NOZE. The purpose was to discover the cause of a confimed depletion of ozone in the Earth's atmosphere over Antarctica. In just two months, the team led by Solomon of NOAA and Hoffman, who was then at the University of Wyoming, learned most of what we know about the ozone hole, particularly the role chlorofluorocarbons, or CFCs, in destroying the ozone layer--which protects the Earth from ultraviolet radiation.........

Posted by: Tyler      Permalink         Source

August 18, 2006, 6:23 AM CT

How Light Pushes Atoms

A research paper would be reported in the 18 August edition of the journal Physical Review Letters reveals a new effect in the fundamental way that laser light interacts with atoms. "Unlike water, which speeds up as it passes through a small nozzle, photons of light have less momentum at the center of a focused laser beam," says Kurt Gibble, an associate professor of physics at Penn State University and the author of the research paper. Gibble's theoretical paper analyzes the speed of an atom after it absorbs a photon of light and reveals the surprising effect that a photon in a narrow laser beam delivers less momentum to an atom than does a photon in a wide beam of light.

Einstein proposed that a light wave is made of photons that carry discrete packets of energy. "When a photon hits an atom, the atom recoils with a speed that is determined by the photon's momentum, similar to two balls colliding on a billiard table," Gibble explains. Physicists often think of a focused laser beam as the intense intersection of two or more infinitely wide light waves, and Gibble's discovery provides an important new understanding of what happens to an atom that is pummeled by photons coming from the different directions of these multiple intersecting light waves. "You might believe that an atom would absorb a photon randomly from only one of the beams, but this paper shows that the atom feels the effect of the photons from all of the beams simultaneously and, surprisingly, that it recoils with a speed that is less than it would get from the momentum of any one of the infinitely wide photons".........

Posted by: Kevin      Permalink         Source

August 17, 2006, 11:03 PM CT

Web Database For Ionic Liquid Data

Chemical engineers and others designing "green" industrial processes using new ionic liquid solvents now have an important new resource, an on-line database of physical properties developed by the National Institute of Standards and Technology (NIST).

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

August 7, 2006, 11:51 PM CT

The oxygen balance

Oxygen is one of the most significant keys to deciphering past climates. Oxygen comes in heavy and light varieties, or isotopes, which are useful for paleoclimate research. Like all elements, oxygen is made up of a nucleus of protons and neutrons, surrounded by a cloud of electrons. All oxygen atoms have 8 protons, but the nucleus might contain 8, 9, or 10 neutrons. "Light" oxygen-16, with 8 protons and 8 neutrons, is the most common isotope found in nature, followed by much lesser amounts of "heavy" oxygen-18, with 8 protons and 10 neutrons.

The ratio (relative amount) of these two types of oxygen in water changes with the climate. By determining how the ratio of heavy and light oxygen in marine sediments, ice cores, or fossils is different from a universally accepted standard, scientists can learn something about climate changes that have occurred in the past. The standard scientists use for comparison is based on the ratio of oxygen isotopes in ocean water at a depth of 200-500 meters.

What climate factors influence the ratio of oxygen isotopes in ocean water?

Evaporation and condensation are the two processes that most influence the ratio of heavy oxygen to light oxygen in the oceans. Water molecules are made up of two hydrogen atoms and one oxygen atom. Water molecules containing light oxygen evaporate slightly more readily than water molecules containing a heavy oxygen atom. At the same time, water vapor molecules containing the heavy variety of oxygen condense more readily.........

Posted by: Sarah      Permalink         Source

August 4, 2006, 0:21 AM CT

Answer To A 20-year-old Metal Question

What happens to metals when you bend them? The question isn't as easy as you may think. A research team from the National Institute of Standards and Technology (NIST), Oak Ridge National Laboratory (ORNL), and the University of Southern California, using a unique X-ray probe, has gathered the first direct evidence showing that, on average, a 20-year-old model is a useful predictor of stresses and strains in deformed metal.*.

But the measurements also show that averages can be deceiving. They mask extremely large variations in stresses that, until now, had gone on undetected. The experiments have implications for important practical problems in sheet metal forming and control of metal fatigue, which is responsible for a number of structural materials failures.

When metals deform, the neat crystal structure breaks into a complex three-dimensional web of crystal defects called "dislocation walls" that enclose cells of dislocation-free material. The effect is like micron-sized bubbles in foam. These complex dislocation structures are directly responsible for the mechanical properties of virtually all metals, and yet they remain very poorly understood in spite of decades of research. Twenty years ago, the German researcher Häel Mughrabi theorized that the stresses in the dislocation walls and the cell interiors would be different and have opposite signs--an important result for modeling the effects of shaping and working metal on its properties. Until now there has only been indirect evidence for Mughrabi's model because of the problem of precisely measuring stress at the micron level in individual cells in the dislocation structure.........

Posted by: Sarah      Permalink         Source

August 3, 2006, 7:09 AM CT

Future Quantum Research

Although presently a very young field, Quantum Information Science and Technology (QIST) could well have a vital role to play in future information and communication technologies. Quantum computing and communication techniques have the potential to transform the way we think about computing power.

Or so believes Daniele Binosi of the Institute of Quantum Optics and Quantum Information in Innsbruck, Austria, and the European Centre for Theoretical Studies in Nuclear Physics and Related Areas in Trento, Italy, who has been involved in the first phase of the ERA-Pilot QIST project. "Once we can build a quantum computer, the result will be a revolution much like the initial growth in information technology. It will not be so much an evolution in processing power as a revolution. We cannot even imagine now the increase in processing power that will become available".

The aims of ERA-Pilot QIST are to foster European research efforts in QIST by investigating the present status of quantum research in Europe, identifying the potential for cooperation between research groups, and making recommendations for future research and funding policy at both national and European level. Collaborating with other related projects, it is part of the Future and Emerging Technologies (FET) proactive initiative in the field of Quantum Information Processing and Communication (QIPC). Since 1998, throughout FP5 and FP6 - the EU's Fifth and Sixth Framework Programmes for research, FET has funded projects in this area of research for a total of €100 million.........

Posted by: Kevin      Permalink         Source

July 26, 2006, 8:46 PM CT

The Chemistry Behind Lightsticks

Almost everyone has seen a lightstick. A lightstick is a plastic tube with a glass vile inside it. When the tube is bent, the vial breaks allowing the chemicals to mix and react. The colorfully glowing sticks utilize a chemical process called chemiluminescence where energy is released in the form of light. The most common lightsticks use chemiluminescence with colored tubes to provide the desired color.

This process is not caused by heat and may not produce heat, but the speed of reaction is still dependence on environmental heat. The colder the environment, the slower the reaction and will glow longer.

Lightsticks have three parts. There are two chemicals that react to release energy which is converted to light. Usually, commercial lightsticks utilize the reaction between hydrogen peroxide and acetonitrile. When the glass vile is broken and the two chemicals are mixed, it will release enough energy to excite the electrons in the oxygen to cause the electrons to jump to a higher energy level and then fall back releasing light.

Specifically, the hydrogen peroxide oxidizes the acetonitril eventually forming excited oxygen. This decomposes and releases the energy as light as can be seen stepwise above.

More on chemiluminescence can be found here on "A Chemiluminescence Reaction between Hydrogen Peroxide and Acetonitrile and Its Applications".........

Posted by: Sarah      Permalink         Source

July 22, 2006, 10:45 PM CT

Watching Real-time Chemical Activity In Cells

Attempts to identify potential drugs that interfere with the action of one particular enzyme linked to heart disease and similar health problems led scientists at Johns Hopkins to create a new tool and new experimental approach that allow them to see multiple, real-time chemical reactions in living cells. Their report on the work is published July 21 in the journal ACS Chemical Biology.

Most current drug development operations test chemicals on enzymes isolated from their normal environs and then take further steps to see if the chemical can get into the cell to do its work, and figure out how poisonous the chemical is to a cell.

"Living cells are critical to our work because they show us how and what is actually happening in a normal context and time span when a chemical is added," says Jin Zhang, Ph.D., an assistant professor of pharmacology and molecular sciences in Hopkins' Institute for Basic Biomedical Sciences.

Testing chemicals on enzymes in living cells provides the opportunity to find potential drugs that work in new ways. For example, using living cells allows researchers to "see" where in the cell chemicals do their work. Scientists could then design new drugs to go to specific places within cells to work more efficiently. Also, streamlining the one-at-a-time approach offers the chance to study - and rule out or in - many potentially useful chemicals at once.........

Posted by: Sarah      Permalink         Source

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