Monday, May 17, 2010


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Radio frequency identification, RFID, could be used in the immediate aftermath of a major earthquake to save lives, according to new research published in the International Journal of Innovation and Sustainable Development.

Yen-Chun Jim Wu of the National Sun Yat-Sen University and Ching-Yuan Hung, of the National Kaohsiung First University of Science & Technology, in Taiwan, that there is a 'golden' rescue period following an earthquake, which lasts just 72 hours. During this time the efficiency of emergency response procedures is key to the rescue operation, especially given the possibility of aftershocks and continued risk caused by collapsing buildings, fires and gas explosions. Particularly challenging is knowing how many people are present in a building, a hospital or school, for instance.

"Continuously updated information on casualties and losses must be made available to disaster response managers in real time so that they can arrange and deploy relief supplies in an appropriate and timely manner," the researchers say. RFID could be applied to help provide such real-time information, allowing for quicker and more efficient dispatching of rescue personnel and more precisely organized search and rescue missions following an earthquake. They have used the Sichuan earthquake (magnitude 8.0) of May 2008. 100 magnitude 4.0 aftershocks hit the area following the disaster as a model for studying how RFID might be used in such a situation. However, the concepts would be equally applicable to other disasters.

They have devised a deployment of RFID that could potentially mitigate a wide array of post-disaster logistical challenges, such as allowing rescuers and the emergency services to manage and monitor transferred evacuees and to control the flow of medical and other supplies.

Practically speaking, however, not every building can keep a pre-disaster record of its activity or install a security system that is suitable for coping with disasters, the team concedes. However, a practical count of the number of people trapped at certain public venues, offices, hospitals and schools that have already been equipped with RFID technology could be made possible. "Office workers would have their identity badges embedded in their RFID tags, while visitors would be given temporary RFID tags when they enter the lobby," they suggest. Similarly, identity tags for hospital staff and patients could embed RFID technology. There is an ethical and moral dimension to tagging schoolchildren and students or members of the public, of course.

Assuming that technological, logistic and ethical issues could be easily addressed, RFID readers installed at entry and exit points and around critical areas in a building would provide critical information about people's movements and whether or not they had escaped the building following a disaster. "Rescue personnel could gain a more precise read on the location of those trapped and helping to avoid inefficient search and rescue efforts," the team says.

Inderscience Enterprises


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Researchers at Johns Hopkins have discovered that a compound in dark chocolate may protect the brain after a stroke by increasing cellular signals already known to shield nerve cells from damage.

Ninety minutes after feeding mice a single modest dose of epicatechin, a compound found naturally in dark chocolate, the scientists induced an ischemic stroke by essentially cutting off blood supply to the animals' brains. They found that the animals that had preventively ingested the epicatechin suffered significantly less brain damage than the ones that had not been given the compound.

While most treatments against stroke in humans have to be given within a two- to three-hour time window to be effective, epicatechin appeared to limit further neuronal damage when given to mice 3.5 hours after a stroke. Given six hours after a stroke, however, the compound offered no protection to brain cells.

Sylvain Doré, Ph.D., associate professor of anesthesiology and critical care medicine and pharmacology and molecular sciences at the Johns Hopkins University School of Medicine, says his study suggests that epicatechin stimulates two previously well-established pathways known to shield nerve cells in the brain from damage. When the stroke hits, the brain is ready to protect itself because these pathways — Nrf2 and heme oxygenase 1 — are activated. In mice that selectively lacked activity in those pathways, the study found, epicatechin had no significant protective effect and their brain cells died after a stroke.

The study now appears online in the Journal of Cerebral Blood Flow and Metabolism.

Eventually, Doré says, he hopes his research into these pathways could lead to insights into limiting acute stroke damage and possibly protecting against chronic neurological degenerative conditions, such as Alzheimer's disease and other age-related cognitive disorders.

The amount of dark chocolate people would need to consume to benefit from its protective effects remains unclear, since Doré has not studied it in clinical trials. People shouldn't take this research as a free pass to go out and consume large amounts of chocolate, which is high in calories and fat. In fact, people should be reminded to eat a healthy diet with a variety of fruits and vegetables.

Scientists have been intrigued by the potential health benefits of epicatechin by studying the Kuna Indians, a remote population living on islands off the coast of Panama. The islands' residents had a low incidence of cardiovascular disease. Scientists who studied them found nothing striking in the genes and realized that when they moved away from Kuna, they were no longer protected from heart problems. Researchers soon discovered the reason was likely environmental: The residents of Kuna regularly drank a very bitter cocoa drink, with a consistency like molasses, instead of coffee or soda. The drink was high in the compound epicatechin, which is a flavanol, a flavanoid-related compound.

But Doré says his research suggests the amount needed could end up being quite small because the suspected beneficial mechanism is indirect. "Epicatechin itself may not be shielding brain cells from free radical damage directly, but instead, epicatechin, and its metabolites, may be prompting the cells to defend themselves," he suggests.

The epicatechin is needed to jump-start the protective pathway that is already present within the cells. "Even a small amount may be sufficient," Doré says.

Not all dark chocolates are created equally, he cautions. Some have more bioactive epicatechin than others.

"The epicatechin found in dark chocolate is extremely sensitive to changes in heat and light" he says. "In the process of making chocolate, you have to make sure you don't destroy it. Only few chocolates have the active ingredient. The fact that it says 'dark chocolate' is not sufficient."

The Johns Hopkins University


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A single, very unusual family with Tourette syndrome (TS) has led Yale School of Medicine researchers to identify a rare mutation in a gene that is required to produce histamine. The finding provides a new framework to understand many years of data on the role of histamine function in the brain and points to a potentially novel approach to treatment of tics and Tourette.

The study is published online May 5 in the New England Journal of Medicine by a team led by Matthew State, M.D., the Donald J. Cohen Associate Professor in the Yale Child Study Center and in the Departments of Psychiatry and Genetics, and co-director of the Yale Program on Neurogenetics.

TS is a relatively common neurological disorder characterized by tics—involuntary, rapid, sudden movements or vocalizations that occur repeatedly in the same way. It affects as many as one of 100 school-age children. Tics begin in mid-childhood and peak at the start of adolescence. TS is not life threatening, but can be disabling. Affected children and adults commonly have other neuropsychiatric disorders including ADHD, obsessive-compulsive disorder or depression.

Based on strong evidence that genes contribute to TS, the State lab has been searching for rare genetic mutations causing TS for over a decade, in the hopes of gaining a better understanding of the cause of the disorder, and finding opportunities to develop more effective treatments. "Rare families have been used in a variety of other common conditions to help identify underlying mechanisms of disease and find new approaches to treatment," said first author and Yale post-doctoral fellow Adife Gulhan Ercan-Sencicek. "We thought we could use the same approach in Tourette syndrome."

State and his team found a family with TS with a rare mutation in a gene called 1-histidine de carboxylase (HDC). This gene makes a protein that is required for the production of histamine. Histamine is known more often for its role in allergic response, but it is an important neurotransmitter that influences a variety of brain functions.

The father and all eight offspring were diagnosed with TS. The mother and her family did not have the disorder. Two children and the father also had obsessive-compulsive disorder. The State lab took DNA samples from all family members, found the one region of the genome that all affected individuals shared, and then identified a rare mutation in HDC within this region, which resulted in the mutated protein losing its function.

State said past work on brain histamine by other labs shows that mice with low levels are more prone to repetitive behaviors that are similar to human tics, and that increasing brain histamine reverses this problem.

"The opportunity to go directly from a rare genetic finding to a trial of a new approach to treatment in a neuropsychiatric disorder is very unusual," said State. "We were lucky to happen across a gene pointing to a well-studied area in neuroscience. There are several new medications in development that increase the release of brain histamine. Based on this genetic finding, these compounds would be good candidates for new treatments for Tourette."

(Photo: Yale University, Matthew State)

Yale University


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Renewable electricity can be transformed into a substitute for natural gas. Until now, electricity was generated from gas. Now, a German-Austrian cooperation wants to go in the opposite direction. In the future, these researchers and entrepreneurs would like to store surplus electricity – such as from wind power or solar energy – as climate-neutral methane, and store it in existing gas storage facilities and the natural gas network.

Throughout the world, electricity generation is based more and more on wind and solar energy. So far, the missing link for integrating renewable energy into the electricity supply is a smart power storage concept. Because when the wind is blowing powerfully, wind turbines generate more electricity than the power grid can absorb. Now, German researchers have succeeded in storing renewable electricity as natural gas. They convert the electricity into synthetic natural gas with the aid of a new process. The process was developed by the Center for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW), in cooperation with the Fraunhofer Institute for Wind Energy and Energy System Technology IWES. Currently, Solar Fuel Technology, the Austria-based partner company, is setting up the industrial implementation of the process. One advantage of the technology: it can use the existing natural gas infrastructure. A demonstration system built on behalf of Solar Fuel in Stuttgart is already operating successfully. By 2012, a substantially larger system – in the double-digit megawatt range – is planned to be launched.

For the first time, the process of natural gas production combines the technology for hydrogen-electrolysis with methanisation. "Our demonstration system in Stuttgart splits water using surplus renewable energy using electrolysis. The result is hydrogen and oxygen," explains Dr. Michael Specht of ZSW. "A chemical reaction of hydrogen with carbon dioxide generates methane – and that is nothing other than natural gas, produced synthetically."

With the rapid expansion of renewable energies, the need for new storage technologies grows massively. This is of special interest for energy utilities and power companies. "So far, we converted gas into electricity. Now we also think in the opposite direction, and convert electricity into ’real natural’ gas," explains Dr. Michael Sterner of Fraunhofer IWES, who is investigating engineering aspects and energy system analysis of the process. "Surplus wind and solar energy can be stored in this manner. During times of high wind speeds, wind turbines generate more power than is currently needed. This surplus energy is being more frequently reflected at the power exchange market through negative electricity prices." In such cases, the new technology could soon keep green electricity in stock as natural gas or renewable methane.

"Within the development of this technology, ZSW has been guided by two core issues," explains Michael Specht: "Which storage systems offer sufficient capacity for compensating fluctuating renewable energies that depend on the wind and weather? And which storage systems can be integrated into the existing infrastructure the easiest?"

The storage reservoir of the natural gas network extending through Germany is vast: It equals more than 200 terawatt hours – enough to satisfy consumption for several months. The power network has only a capacity of 0.04 terawatt hours by itself. The integration into the infrastructure is simple: The natural gas substitute can be stored like conventional natural gas in the supply network, pipelines and storage systems, in order to drive natural gas cars or fire natural gas heating systems.

The new technology aims at facilitating the integration of high shares of fluctuating power generation from renewable energies into the energy system. One goal is to structure the delivery of power from wind parks on a scheduled and regular basis. "The new concept is a game changer and a new significant element for the integration of renewable energies into a sustainable energy system," adds Sterner. The efficiency of converting power to gas equals more than 60 percent. "In our opinion, this is definitely better than a total loss," says Michael Specht. A total loss looms if, for instance, wind power has to be curtailed. The predominant storage facility to date – pumped hydro power plants – can only be expanded to a limited extent in Germany.

In order to push the new energy conversion technology forward, the two German research institutes have joined together with the company Solar Fuel Technology of Salzburg. Starting in 2012, they intend to launch a system with a capacity of approximately 10 megawatt.

Fraunhofer Institute


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Researchers have found evidence that "marine snow"--aggregates of organic material floating in water bodies--may act as microscopic, island-like refuges for pathogens, or disease-causing organisms. This detritus may skew water sampling procedures and mathematical models used to predict the transmission of waterborne diseases to humans.

The scientists responsible for these findings, funded by a National Science Foundation (NSF)-National Institutes of Health (NIH) Ecology of Infectious Diseases (EID) grant, published their results in the journal ISLANDS OF GERMS: RESEARCHERS DISCOVER PATHOGENS FLOATING ON TINY.

The findings are the first to compare the existence of pathogens on marine snow with the way insects, amphibians and other creatures establish homes and persist on remote islands in the oceans.

Theories in island biogeography--the study of the factors that affect species richness on islands--also apply to microscopic drifting aggregates, according to Maille Lyons, a scientist at Old Dominion University (ODU) and lead author of the paper, with ODU co-authors Fred Dobbs and Holly Gaff. Other authors are J. Evan Ward of the University of Connecticut; Randall Hicks of the University of Minnesota, Duluth; and John Drake of the University of Georgia.

"These predictions help explain whether and for how long bacteria can thrive on an individual aggregate," said Lyons, "and the relationship between the size of the aggregate and the diversity of species found on it."

"This study shows that theory developed for the 'macroscopic' world applies equally to the microscopic one," said Sam Scheiner, program director in NSF's Division of Environmental Biology, which co-funds the EID program with NSF's Directorate for Geosciences.

"It allows scientists to link the small to the large," said Scheiner, "and to provide predictive tools for understanding disease transmission."

Aggregates are made up of small bits of detritus and other components--some of which are living organisms--that usually aren't visible to the naked eye. When these tiny components come in contact with each other, they clump together.

The scientists are evaluating the degree to which detritus-based organic aggregates provide a favorable microclimate for aquatic pathogens.

These "refuges" seem to protect pathogens from stressors such as sunlight and salinity changes, and from predators. They also may provide sources of nourishment for the pathogens.

"If the microclimate is favorable, aggregates likely facilitate the persistence, prevalence and dispersal of aquatic pathogens," said Dobbs.

The researchers found an increased metabolic response, and diversity of bacteria, on individual organic aggregates compared to the surrounding water, indicating that aggregates may be potential reservoirs and vectors for aquatic pathogens.

Current models of the transmission of waterborne diseases and illnesses, however, don't consider the benefits microorganisms gain from hitching a ride on marine snow.

"We've shown, for example, that vibrios [a type of pathogen] proliferate in aggregates and decline in adjacent, aggregate-free water," the journal paper states.

When water sampling is conducted--to determine whether recreational waters should be open to swimmers, or whether shellfish beds should be closed to fishers--aggregates lend a hit-or-miss aspect to the testing.

A sample might include only water without aggregates, giving false-negative results that no danger exists.

"The presence or absence of a single aggregate in an environmental water sample," said Dobbs, "could drastically alter the measure of bacterial concentrations."

(Photo: WHOI)

National Science Foundation


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The brains of problem gamblers react more intensely to near misses than casual gamblers, new research from the University of Cambridge has found. The results could help explain what keeps problem gamblers betting even though they keep losing.

The study involved scanning the brains of 20 gamblers using functional magnetic resonance imaging while they played a computerised slot machine. Participants' gambling habits ranged from regular, social gamblers to those with severe problem gambling.

Dr Luke Clark of the University of Cambridge, who led the study, found that the parts of the brain involved in reward processing – the so-called dopamine centres – were more active in problem gamblers than in social gamblers.

During the experiment, volunteers played a computerised slot machine with two spinning wheels of icons and won 50p when the two icons matched. An icon mismatch was a loss, but when the wheels stopped within one icon of a match, the outcome was considered a "near miss."

Dr Clark found that near misses activated the same brain pathways as wins, even though no reward was given, and that this reaction was stronger in those gamblers who had more symptoms of problem gambling.

In particular, the study found strong responses in the midbrain, an area that is packed with dopamine-releasing brain cells. The dopamine system is associated with addiction and targeted by drugs of abuse. The study also found the near misses were linked with increased activity in a brain region called the ventral striatum, an area associated with reward and learning.

The results help explain why problem gamblers find it hard to give up.

According to Dr Clark: "These findings are exciting because they suggest that near-misses may elicit a dopamine response in the more severe gamblers, despite the fact that no actual reward is delivered. If these bursts of dopamine are driving addictive behaviour, this may help to explain why problem gamblers find it so difficult to quit."

Dopamine, a neurotransmitter, plays an important role in signalling "rewards" such as money and chocolate, and the dopamine system is also targeted by drugs of abuse.

"The results highlight some of the links between problem gambling and drug addiction, and have implications for both psychological and drug treatment for problem gamblers," Dr Clark says.

The findings are published in the new issue of the Journal of Neuroscience.

(Photo: U. Cambridge)

University of Cambridge




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