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3000-year-old furnace rebuilt by archaeologist
A team led by a Cardiff University archaeologist has reconstructed a 3,000-year-old glass furnace, showing that Ancient Egyptian glassmaking methods were much more advanced than previously thought.Dr Paul Nicholson, of the University’s School of History and Archaeology, is leader of an Egypt Exploration Society team working on the earliest fully excavated glassmaking site in the world. The site, at Amarna, on the banks of the Nile, dates back to the reign of Akhanaten (1352 - 1336 B.C.), just a few years before the rule of Tutankhamun.It was previously thought that the Ancient Egyptians may have imported their glass from the Near East at around this time. However, the excavation team believes the evidence from Amarna shows they were making it themselves, possibly in a single stage operation. Dr Nicholson and his colleague Dr Caroline Jackson of Sheffield University demonstrated this was possible, using local sand to produce a glass ingot from their own experimental reconstruction of a furnace near the site.The team have also discovered that the glassworks was part of an industrial complex which involved a number of other high temperature manufacturing processes. The site also contained a potter’s workshop and facilities for making blue pigment and faience - a material used in amulets and architectural inlays. The site was near one of the main temples at Amarna and may have been used to produce materials in state buildings.Dr Nicholson, who has been working at Amarna since 1983, said: “It has been argued that the Egyptians imported their glass and worked it into the artefacts that have been discovered from this time. I believe there is now enough evidence to show that skilled craftsmen could make their own glass and were probably involved in a range of other manufacturing industries as well.”
Source: Cardiff University
Scientists have discovered what they think may be another reason why Greenland 's ice is melting: a thin spot in Earth's crust is enabling underground magma to heat the ice.
They have found at least one “hotspot” in the northeast corner of Greenland -- just below a site where an ice stream was recently discovered.
The researchers don't yet know how warm the hotspot is. But if it is warm enough to melt the ice above it even a little, it could be lubricating the base of the ice sheet and enabling the ice to slide more rapidly out to sea.
“The behavior of the great ice sheets is an important barometer of global climate change,” said Ralph von Frese, leader of the project and a professor of earth sciences at Ohio State University. “However, to effectively separate and quantify human impacts on climate change, we must understand the natural impacts, too.
“Crustal heat flow is still one of the unknowns -- and it's a fairly significant one, according to our preliminary results.”
Timothy Leftwich, von Frese's former student and now a postdoctoral engineer at the Center for Remote Sensing of Ice Sheets at the University of Kansas, presented the study's early results at the American Geophysical Union meeting in San Francisco.
von Frese's team combined gravity measurements of the area taken by a Naval Research Laboratory aircraft with airborne radar measurements taken by research partners at the University of Kansas. The combined map revealed changes in mass beneath the Earth's crust, and the topography of the crust where it meets the ice sheet.
Below the crust is the mantle, the partially molten rocky layer that surrounds the Earth's core. The crust varies in thickness, but is usually tens of miles thick. Even so, the mantle is so hot that temperatures just a few miles deep in the crust reach hundreds of degrees Fahrenheit, von Frese explained.
“Where the crust is thicker, things are cooler, and where it's thinner, things are warmer. And under a big place like Greenland or Antarctica , natural variations in the crust will make some parts of the ice sheet warmer than others,” he said.
The ice thickness, the temperature at the base of the ice, and ground topography all contribute to the forming of an ice stream -- a river of ice that flows within a larger ice sheet. In recent years, Greenland ice streams have been carrying ice out to sea faster, and ice cover on the island has been diminishing.
Once the ice reaches the sea, it melts, and global sea levels rise.
“The complete melting of these continental ice sheets would put much of Florida, as well as New Orleans, New York City and other important coastal population centers, under water,” von Frese said.
The ice sheet in northeast Greenland is especially worrisome to scientists. It had no known ice streams until 1991, when satellites spied one for the first time. Dubbed the Northeastern Greenland Ice Stream, it carries ice nearly 400 miles, from the deepest interior of the island out to the Greenland Sea.
“Ice streams have to have some reason for being there. And it's pretty surprising to suddenly see one in the middle of an ice sheet,” von Frese said.
The newly discovered hotspot is just below the ice stream, and could have caused it to form, the researchers concluded. But what caused the hotspot to form"
“It could be that there's a volcano down there,” he said. “But we think it's probably just the way the heat is being distributed by the rock topography at the base of the ice.”
Collaborator Kees van der Veen began working on the project when he was a visiting associate professor of geological sciences and research scientist at Byrd Polar Research Center at Ohio State. He is now at the University of Kansas.
“Recent observations indicate that the Greenland Ice Sheet is much more active than we ever believed,” van der Veen said. “There have been rapid changes in outlet glaciers, for example. Such behavior is critically linked to conditions at the ice bed. Geothermal heat is an important factor, but until now, our models have not included spatial variations in heat, such as this hotspot.
“Our map is the first attempt at quantifying spatial variations in geo-heat under Greenland -- and it explains why the Northeast Greenland Ice Stream is where it is,” van der Veen added.
To measure actual temperatures beneath the ice, scientists must drill boreholes down to the base of the ice sheet-- a mile or more below the ice surface. The effort and expense make such measurements few and far between, especially in remote areas of northeast Greenland.
For now, the researchers are combining theories of how heat flows through the mantle and crust with the gravity and radar data, to understand how the hotspot is influencing the ice.
Once they finish searching the rest of Greenland for other hotspots, they hope to turn their attention to Antarctica.Source: Ohio State University
Ireland Cancer Center of University Hospitals Case Medical Center researchers have recently made great strides in stem cell gene therapy research by transferring a new gene to cancer patients, via their own stem cells, with the ultimate goal of being able to use stronger chemotherapy treatment with less severe side effects. Under this protocol, MGMT, a drug-resistance gene, is added into purified hematopoietic stem cells to protect these cells from the damage of chemotherapy regimens.
In one of 24 presentations by Ireland Cancer Center researchers at the annual American Society of Hematology meeting, Stanton Gerson and colleagues presented that eight patients were enrolled on the trial and six were infused with their own stem cells which were engineered to carry the MGMT gene. In three patients, stem cells carrying the gene were identified in their blood or bone marrow. In one patient, stem cells carrying the gene were detected up to 28 weeks after their administration. This significant finding has never been reported before with this gene and drug combination.
This study is the first to show the success of treatment with evidence that stem cells now carry the new gene, says Dr. Gerson, Director of the Ireland Cancer Center and Case Comprehensive Cancer Center, who spearheaded the Phase I study along with a team of researchers. ¡§These patients show the success of treatment with evidence that their stem cells now carry the new genes. This is a breakthrough the first time selection with MGMT has been shown to occur in patients.
Preclinical animal research, conducted by Dr. Gerson and his colleagues, has shown that the gene G156A-MGMT can provide stem cells with very high levels of drug resistance, compared to normal stem cells not carrying the gene. In the Phase I trial for patients with advanced malignancies, researchers collected peripheral blood stem cells from patients and exposed them to a retrovirus containing the G156A-MGMT gene.
Source: University Hospitals of Cleveland
Findings suggest we are becoming more different, not alike
Countering a common theory that human evolution has slowed to a crawl or even stopped in modern humans, a new study examining data from an international genomics project describes the past 40,000 years as a time of supercharged evolutionary change, driven by exponential population growth and cultural shifts.
In a study published in the Proceedings of the National Academy of Sciences (PNAS), a team led by University of Wisconsin-Madison anthropologist John Hawks estimates that positive selection just in the past 5,000 years alone — around the period of the Stone Age — has occurred at a rate roughly 100 times higher than any other period of human evolution. Many of the new genetic adjustments are occurring around changes in the human diet brought on by the advent of agriculture, and resistance to epidemic diseases that became major killers after the growth of human civilizations.
“In evolutionary terms, cultures that grow slowly are at a disadvantage, but the massive growth of human populations has led to far more genetic mutations,” says Hawks. “And every mutation that is advantageous to people has a chance of being selected and driven toward fixation. What we are catching is an exceptional time.”
The findings may lead to a very broad rethinking of human evolution, Hawks says, especially in the view that modern culture has essentially relaxed the need for physical genetic changes in humans to improve survival. Adds Hawks: “We are more different genetically from people living 5,000 years ago than they were different from Neanderthals.”
While the correlation between population size and natural selection is nothing new — it was a core premise of Charles Darwin, Hawks says — the ability to bring quantifiable evidence to the table is a new and exciting outgrowth of the Human Genome Project.
Along with co-author Gregory Cochran, an anthropologist at the University of Utah; and Eric Wang of Affymetrix, Inc., in Santa Clara, Cal.; Hawks analyzed data from the International HapMap Project, short for haplotype mapping. This project is working to catalog genetic similarities and differences in human beings by studying genes from distinct sample populations around the globe. While the HapMap will ultimately be used to identify genes that affect human health, it can also provide a road map of genetic variation from the ancestral human population.
While more than 99 percent of the human genome is common across all humans, the HapMap project is cataloguing the individual differences in DNA called single nucleotide polymorphisms (SNPs). The project has mapped roughly 4 million of the estimated 10 million SNPs in the human genome. More importantly, it is identifying different regions of DNA, or haplotypes, that contain a large number of SNPs and are shared by multiple individuals.
In the hunt for recent genetic variation in this map, Hawks’ research focuses on a phenomenon called linkage disequilibrium (LD). These are places on the genome where genetic variations are occurring more often than can be accounted for by chance, usually because these changes are affording some kind of selection advantage.
The researchers identify recent genetic change by finding long blocks of DNA base pairs that are connected. Because human DNA is constantly being reshuffled through recombination, a long, uninterrupted segment of LD is usually evidence of positive selection. Linkage disequilibrium decays quickly as recombination occurs across many generations, so finding these uninterrupted segments is strong evidence of recent adaptation, Hawks says.
Employing this test, the researchers found evidence of recent selection on approximately 1,800 genes, or 7 percent of all human genes.
This finding runs counter to conventional wisdom in many ways, Hawks says. For example, there’s a strong record of skeletal changes that clearly show people became physically smaller, and their brains and teeth are also smaller. This is generally seen as a sign of relaxed selection – that size and strength are no longer key to survival.
But other pathways for evolution have opened, Hawks says, and genetic changes are now being driven by major changes in human culture. One good example is lactase, the gene that helps people digest milk. This gene normally declines and stops activity about the time one becomes a teenager, Hawks says. But northern Europeans developed a variation of the gene that allowed them to drink milk their whole lives — a relatively new adaptation that is directly tied to the advance of domestic farming and use of milk as an agricultural product.
The biggest new pathway for selection relates to disease resistance, Hawks says. As people starting living in much larger groups and settling in one place roughly 10,000 years ago, epidemic diseases such as malaria, smallpox and cholera began to dramatically shift mortality patterns in people. Malaria is one of the clearest examples, Hawks says, given that there are now more than two dozen identified genetic adaptations that relate to malaria resistance, including an entirely new blood type known as the Duffy blood type.
Another recently discovered gene, CCR5, originated about 4,000 years ago and now exists in about 10 percent of the European population. It was discovered recently because it makes people resistant to HIV/AIDS. But its original value might have come from obstructing the pathway for smallpox.
“There are many things under selection that are making it harder for pathogens to kill us,” Hawks says.
Population growth is making all of this change occur much faster, Hawks says, giving a nod to Charles Darwin. When Darwin wrote in “Origin of the Species” about challenges in animal breeding, he always emphasized that herd size “is of the highest importance for success” because large populations have more genetic variation, Hawks says.
The parallel to humans is obvious: The human population has grown from a few million people 10,000 years ago to about 200 million people at 0 AD, to 600 million people in the year 1700, to more than 6.5 billion today. Prior to these times, the population was so small for so long that positive selection occurred at a glacial pace, Hawks says.
“What’s really amazing about humans, that is not true with most other species, is that for a long time we were just a little ape species in one corner of Africa, and weren’t genetically sampling anything like the potential we have now,” he says.
The recent changes are especially striking, he says. “Five thousand years is such a small sliver of time – it’s 100 to 200 generations ago,” he says. “That’s how long it’s been since some of these genes originated, and today they are in 30 or 40 percent of people because they’ve had such an advantage. It’s like ‘invasion of the body snatchers.’”
Source: Proceedings of the National Academy of Sciences
A team of astronomers have used the NASA/ESA Hubble Space Telescope to detect, for the first time, strong evidence of hazes in the atmosphere of a planet orbiting a distant star. The discovery comes after extensive observations made recently with Hubble’s Advanced Camera for Surveys (ACS).
The team, led by Frédéric Pont from the Geneva University Observatory in Switzerland, used Hubble’s ACS to make the first detection of hazes in the atmosphere of the giant planet. "One of the long-term goals of studying extrasolar planets is to measure the atmosphere of an Earth-like planet, this present result is a step in this direction" says Pont. "HD 189733b is the first extrasolar planet for which we are piecing together a complete idea of what it really looks like."
The new observations were made as the extrasolar planet, dubbed HD 189733b, passed in front of its parent star in a transit. As the light from the star passes through the atmosphere around the limb of the giant extrasolar planet, the gases in the atmosphere stamp their unique signature on the starlight from HD 189733.
The planet itself, orbiting close to its parent star, is a ‘hot-Jupiter’ type of gas giant slightly larger than Jupiter. The proximity to its star results in an atmospheric temperature of roughly seven hundred degrees Celsius. Measurements of the way light varies as the planet passes in front of its parent star indicates that HD 189733b has neither Earth-sized moons nor any discernable Saturn-like ring system.
Hubble’s ACS camera, coupled with a grism (a kind of cross between a prism and a diffraction grating) allowed the astronomers to make extremely accurate measurements of the spectrum of HD 189733b, allowing conclusions to be drawn about the composition of the planet’s atmosphere. The exquisite level of precision needed to make this observation can only, at the moment, be achieved from space. The combination of a large planet and relatively small parent star – only 76% of the diameter of our Sun – contributes to the success of this delicate experiment.
Where the scientists had expected to see the fingerprints of sodium, potassium and water there were none. This finding, combined with the distinct shape of the planet’s spectrum, infers that high level hazes (with an altitude range of roughly 1000 km) are present. So the atmosphere on HD 189733b would look very similar to a gorgeous red sunset over Athens! Venus and Saturn’s moon Titan, in our own Solar System, are also covered with haze. According to the scientists the haze probably consists of tiny particles (less than 1/1000 mm in size) of condensates of iron, silicates and aluminium oxide dust (the compound on Earth which the mineral sapphire is made of).
As part of the observations of HD 189733, the teams of astronomers also needed to accurately account for the variations in the star’s brightness during the set of observations. ‘Starspots’ like those seen on our own Sun may cover several percent of the star and are thought to be about 1000 degrees Celsius cooler than the rest of HD 189733’s surface. It was found that there is a starspot on the star’s surface which is over 80,000 km across.
Source: ESA/Hubble Information Centre
Only second Jurassic dinosaur ever found in Antarctica
A new genus and species of dinosaur from the Early Jurassic has been discovered in Antarctica. The massive plant-eating primitive sauropodomorph is called Glacialisaurus hammeri and lived about 190 million years ago.
The recently published description of the new dinosaur is based on partial foot, leg and ankle bones found on Mt. Kirkpatrick near the Beardmore Glacier in Antarctica at an elevation of more than 13,000 feet.
“The fossils were painstakingly removed from the ice and rock using jackhammers, rock saws and chisels under extremely difficult conditions over the course of two field seasons,” said Nathan Smith, a graduate student at The Field Museum. “They are important because they help to establish that primitive sauropodomorph dinosaurs were more broadly distributed than previously thought, and that they coexisted with their cousins, the true sauropods.”
The findings were published in the Acta Palaeontologica Poloncica (see http://www.app.pan.pl/). Diego Pol, a paleontologist at the Museo Paleontológico Egidio Feruglio in Chubut, Argentina, is the other co-author of the research.
Sauropodomorph dinosaurs were the largest animals to ever walk the earth. They were long-necked herbivores and include Diplodocus and Apatosaurus. Their sister group is the theropods, which include Tyrannosaurus, Velociraptor, and modern birds.
Glacialisaurus hammeri was about 20-25 feet long and weighed about 4-6 tons . It was named after Dr. William Hammer, a professor at Augustana College who led the two field trips to Antarctica that uncovered the fossils. Glacialisaurus belongs to the sauropodomorph family Massopsondylidae, which may represent a secondary radiation of basal sauropodomorphs during the Early Jurassic.
Currently, the development and evolutionary relationships of the sauropodomorph dinosaurs are hotly debated by paleontologists. This discovery, however, helps to resolve some of this debate by establishing two things. First, it shows that sauropodomorphs were widely distributed in the Early Jurassic—not only in China, South Africa, South America and North America, but also in Antarctica.
“This was probably due to the fact that major connections between the continents still existed at that time, and because climates were more equitable across latitudes than they are today,” Smith said.
Second, the discovery of Glacialisaurus hammeri shows that primitive sauropodomorphs probably coexisted with true sauropods for an extended period of time. The recent discovery of a possible sauropod at roughly the same location in Antarctica lends additional evidence to the theory that the earliest sauropods coexisted with their basal sauropodomorph cousins, including Glacialisaurus hammeri, during the Late Triassic and Early Jurassic, Smith and Pol conclude in their research findings.
Source: Acta Palaeontologica Poloncica
The capacity of the human mind to believe or disbelieve a statement is a powerful force for controlling both behavior and emotion, but the basis of these states in the brain is not yet understood. A new study found that belief, disbelief and uncertainty activate distinct regions of the brain, with belief/disbelief affecting areas associated with the pleasantness/unpleasantness of tastes and odors. The study published in the Annals of Neurology (http://www.interscience.wiley.com/journal/ana), the official journal of the American Neurological Association.
Led by Sam Harris of the University of California, Los Angeles, the study involved 14 adults who underwent functional MRI scans during which they were presented with short statements that they had to evaluate as true, false or undecided. Each participant underwent three scans while they evaluated statements from a broad variety of categories such as mathematical, geographical, autobiographical, religious and factual. The statements were designed to be clearly true, false or undecidable.
Contrasting belief and disbelief trials yielded increased signal in the ventromedial prefrontal cortex (VMPFC), which is involved in linking factual knowledge with emotion. “The involvement of the VMPFC in belief processing suggests an anatomical link between the purely cognitive aspects of belief and human emotion and reward,” the authors state. The fact that ethical belief showed a similar pattern of activation to mathematical belief suggests that the physiological difference between belief and disbelief is not related to content or emotional associations, they note.
The contrasts between disbelief and belief showed increased signal in the anterior insula, a region involved in the sensation of taste, the perception of pain, and the feeling of disgust, indicating that “false propositions might actually disgust us,” the authors state. “Our results appear to make sense of the emotional tone of disbelief, placing it on a continuum with other modes of stimulus appraisal and rejection,” they add.
Uncertainty evoked a positive signal in the anterior cingulate cortext (ACC) and a decreased signal in the caudate, a region of the basal ganglia, which plays a role in motor action. Noting that both belief and disbelief showed an increased signal in the caudate compared to uncertainty, the authors suggest that the basal ganglia may play a role in mediating the cognitive and behavioral differences between decision and indecision.
The study raises the possibility that the differences between belief, disbelief and uncertainty may one day be reliably distinguished by neuroimaging techniques. They conclude: “This would have obvious implications for the detection of deception, for the control of the placebo effect during the process of drug design, and for the study of any higher-cognitive phenomenon in which the differences between belief, disbelief, and uncertainty might be a relevant variable.”Source: Annals of Neurology
From Technology ReviewHow might expanding Google's cloud-computing service alter the digital world? To know how you'll be using computers and the Internet in the coming years, it's instructive to consider the Google employee: most of his software and data--from pictures and videos, to presentations and e-mails--reside on the Web. This makes the digital stuff that's valuable to him equally accessible from his home computer, a public Internet café, or a Web-enabled phone. It also makes damage to a hard drive less important. Recently, Sam Schillace, the engineering director in charge of collaborate Web applications at Google, needed to reformat a defunct hard drive from a computer that he used for at least six hours a day. Reformatting, which completely erases all the data from a hard drive, would cause most people to panic, but it didn't bother Schillace. "There was nothing on it I cared about" that wasn't accessible on the Web, he says.......read more
Researchers may be able to develop an antidepressant which takes effect almost immediately by directly targeting novel molecules in the brain instead of taking a less direct route, which can lead to longer times for medication to take effect, according to a new study presented at the American College of Neuropsychopharmacology (ACNP) annual meeting. The antidepressant is also thought to be effective in people for whom previous treatments have been ineffective. This human and rodent research is among the first to examine the effects of rapid antidepressant strategies.
Lead researcher and ACNP member Husseini Manji, director of the mood and anxiety disorders program at the National Institute of Mental Health (NIMH), says one of the major limitations in existing pharmacological treatments for major depression is the time between starting to take the medication, and when it starts to alleviate the depression, often a period of one month or longer. He adds that strategies that work at much faster rates would have a tremendous impact for Americans who suffer from depression – nearly 21 million annually, according to NIMH.
"Today's antidepressant medications eventually end up doing the same thing, but they go about it the long way around, with a lot of biochemical steps that take time. Now we've shown what the key targets are and that we can get at them rapidly," says Dr. Manji. “This research is leading to some very real possibilities for a whole new generation of antidepressant medications."
The study looked at patients in a “difficult to treat” group, meaning individuals who had not responded to other treatments including psychotherapy, traditional antidepressants or electroconvulsive therapy. This group did not attempt all treatment options, like medication. Researchers treated the depressed patients intravenously with ketamine, a general anesthetic usually used for minor surgical procedures in which muscle relaxation is not required. The doses of ketamine used in this study were considerably lower than when it is used as an anesthetic.
Ketamine produced results much more quickly than traditional antidepressants because it acted directly upon critical molecules in important neuronal circuits instead of having to bypass multiple locations en route to those circuits. Typically, currently available antidepressant medications work via serotonin or norepinephrine, neurotransmitters which act within the brain to help regulate emotion and cognition.
The results showed that patients responded after only two hours, and within 24 hours, 70% had responded. Patients were followed over time, and 35% maintained their response for up to one week. Traditional antidepressants usually take many weeks, or even months, to begin to work. “This is intriguing data which suggests that targeting these important molecules in critical circuits would be extremely helpful in treating depression more quickly, before it worsens and becomes more severe,” Dr. Manji said.
The researchers also studied rodents to determine whether they could get medication to highly responsive brain areas more quickly. By looking at different biomarkers – specific physical features used to measure the progress of a disease or condition – in mice and rats, researchers came closer to identifying at what point in the biochemical process medication might become effective, which would ultimately lead to faster treatment.
Treating patients with rapid strategies is essential since some patients who suffer from depression are tempted to stop their medication if it doesn’t work quickly enough.
Ongoing human studies using magnetoencephalography (MEG) are also helping to identify the specific brain circuits through which these rapid antidepressant effects occur. Identifying these precise circuits may lead to the development of molecules with even more precise effects, and therefore fewer side effects.
Source: American College of Neuropsychopharmacology
Nanotubes may have high-tech applications, study involving UCR engineers reports
Two engineers at the University of California, Riverside are part of a binational team that has found semiconducting nanotubes produced by living bacteria – a discovery that could help in the creation of a new generation of nanoelectronic devices.
The research team believes this is the first time nanotubes have been shown to be produced by biological rather than chemical means. It opens the door to the possibility of cheaper and more environmentally friendly manufacture of electronic materials. Study results appeared in the Proceedings of the National Academy of Sciences.
The team, including Nosang V. Myung, associate professor of chemical and environmental engineering in the Bourns College of Engineering, and his postdoctoral researcher Bongyoung Yoo, found the bacterium Shewanella facilitates the formation of arsenic-sulfide nanotubes that have unique physical and chemical properties not produced by chemical agents.
“We have shown that a jar with a bug in it can create potentially useful nanostructures,” Myung said. “Nanotubes are of particular interest in materials science because the useful properties of a substance can be finely tuned according to the diameter and the thickness of the tubes.”
The whole realm of electronic devices which power our world, from computers to solar cells, today depend on chemical manufacturing processes which use tremendous energy, and leave behind toxic metals and chemicals. Myung said a growing movement in science and engineering is looking for ways to produce semiconductors in more ecologically friendly ways.
Two members of the research team, Hor Gil Hur and Ji-Hoon Lee from Gwangju Institute of Science and Technology (GIST), Korea, first discovered something unexpected happening when they attempted to remediate arsenic contamination using the metal-reducing bacterium Shewanella. Myung, who specializes in electro-chemical material synthesis and device fabrication, was able to characterize the resulting nano-material.
The photoactive arsenic-sulfide nanotubes produced by the bacteria behave as metals with electrical and photoconductive properties. The researchers report that these properties may also provide novel functionality for the next generation of semiconductors in nano- and opto-electronic devices.
In a process that is not yet fully understood, the Shewanella bacterium secretes polysacarides that seem to produce the template for the arsenic sulfide nanotubes, Myung explained. The practical significance of this technique would be much greater if a bacterial species were identified that could produce nanotubes of cadmium sulfide or other superior semiconductor materials, he added.“This is just a first step that points the way to future investigation,” he said. “Each species of Shewanella might have individual implications for manufacturing properties.” Source: Proceedings of the National Academy of Sciences
Depression nearly triples the risk of death following a heart attack, even when accounting for other heart attack risk factors, according to research presented at the American College of Neuropsychopharmacology (ACNP) annual meeting, which showed that among 360 depressed, post myocardial infarction patients followed for more than six years, those who did not recover from their depression in the first six months were more than twice as likely to die.
This study was one of several presented at a panel which examined the links between depression and vascular disease. “There is an unequivocal link between depression and heart disease, but it is not clear what causes this link,” said Alexander Glassman, Professor of Psychiatry at Columbia University, College of Physicians and Surgeons.
“There is a whole series of factors that link depression and heart disease and we are just beginning to understand how antidepressants act in people who have these conditions together.” Additional risk factors that tend to be major medical predictors of death from a heart attack include the severity of the heart attack and variability in various measures of heart function during recovery.
Depression has increasingly been recognized to increase the risk for cardiovascular disease. Possible reasons for this association include sticky platelets, a condition depressed patients are likely to have, or autonomic nervous activity, which increases heart irritability.
Ronald S. Duman, professor of psychiatry and pharmacology at Yale University School of Medicine, also presented research on this topic. His work examined molecular mechanisms and the identity of the protein, vascular endothelial growth factor (VEGF). VEGF is a key growth factor in the formation of vascular cells and was originally identified and studied for its role in the formation of vascular tissues.
“We found that different classes of antidepressants increase the expression of VEGF in the hippocampus (the part of the brain which influences memory), which may partly explain how certain antidepressants are more effective than others,” said Duman. “Changes in brain levels of VEGF contribute importantly to the antidepressant response and that’s why studying VEGF function may be useful in developing medications that are more effective and rapid acting.”
The panel also included presentations from Kevin Tracey and Gregory Miller, who presented evidence indicating the brain has significant control over the levels of inflammatory molecules called cytokines in other parts of the body, and that these levels are altered in depression and associated with an increased risk for heart disease. And Charles Nemeroff, and professor and chair of the department of psychiatry at Emory University, presented data showing the impact of stressful events early in life on the response to stress later in life. These events precede either depression or heart disease and could potentially contribute to vulnerability for both conditions.
Source: American College of Neuropsychopharmacology
From The Economist Superimposing computer graphics on the real world, instead of displaying them on screens, has many potential usesFor some things, it turns out, computer graphics can be much more effective when viewed not on screens, but superimposed on the real world. The technique is known as “augmented reality” (AR) or, less frequently, as “augmented vision”, because the real world is augmented with virtual text or graphics. Much AR technology remains in labs, but research funding in both the private and public sectors is increasing, and all kinds of eclectic and ingenious applications are emerging in fields as diverse as medicine, warfare, manufacturing and entertainment........read more
From Technology ReviewA new wave of products targeting the blossoming personal-genomics industry has recently become available. The first commercial whole-genome sequencing service was launched last week by startup Knome, based in Cambridge, MA. Three other companies--deCode Genomics, based in Iceland; and the much-hyped startups 23andMe and Navigenics, both based in California--recently announced consumer services for genome-wide DNA analysis. While the technologies and business strategies of the companies vary, they all aim to give consumers a picture of their genetic risk for disease......read more
Many applications in aviation, more
MIT engineers have designed the first simple process for manufacturing materials that strongly repel oils. The material, which can be applied as a flexible surface coating, could have applications in aviation, space travel and hazardous waste cleanup.
For example, the material could be used to help protect parts of airplanes or rockets that are vulnerable to damage from being soaked in fuel, such as rubber gaskets and o-rings.
“These are vulnerable points in many aerospace applications” said Robert Cohen, the St. Laurent Professor of Chemical Engineering and an author of a paper on the work that will appear in Science.
“It would be nice if you could spill gasoline on a fabric or a gasket or other surface and find that instead of spreading, it just rolled off,” Cohen said. Creating a strongly oil-repelling, or “oleophobic” material, has been challenging for scientists, and there are no natural examples of such a material.
“Nature has developed a lot of methods for waterproofing, but not so much oil-proofing,” said Gareth McKinley, MIT School of Engineering Professor of Teaching Innovation in the Department of Mechanical Engineering and a member of the research team. “The conventional wisdom was that it couldn't be done on a large scale without very special lithographic processes.”
The tendency of oils and other hydrocarbons to spread out over surfaces is due to their very low surface tension (a measure of the attraction between molecules of the same substance).
Water, on the other hand, has a very high surface tension and tends to form droplets. For example, beads of water appear on a freshly waxed car (however, over a period of time, oil and grease contaminate the surface and the repellency fades). That difference in surface tension also explains why water will roll off the feathers of a duck, but a duck coated in oil must be washed with soap to remove it.
The MIT team overcame the surface-tension problem by designing a material composed of specially prepared microfibers that essentially cushion droplets of liquid, allowing them to sit, intact, just above the material's surface.
When oil droplets land on the material, which resembles a thin fabric or tissue paper, they rest atop the fibers and pockets of air trapped between the fibers. The large contact angle between the droplet and the fibers prevents the liquid from touching the bottom of the surface and wetting it.
The microfibers are a blend of a specially synthesized molecule called fluoroPOSS, which has an extremely low surface energy, and a common polymer. They can be readily deposited onto many types of surfaces, including metal, glass, plastic and even biological surfaces such as plant leaves, using a process known as electrospinning.
The researchers have also developed some dimensionless design parameters that can predict how stable the oleophobicity or oil-resistance between a particular liquid and a surface will be. These design equations are based on structural considerations, particularly the re-entrant nature (or concavity) of the surface roughness, and on three other factors: the liquid's surface tension, the spacing of the fibers, and the contact angle between the liquid and a flat surface.
Using these relationships, the researchers can design fiber mats that are optimized to repel different hydrocarbons. They have already created a non-woven fabric that can separate water and octane (jet fuel), which they believe could be useful for hazardous waste cleanup.
The Air Force, which funded the research and developed the fluoroPOSS molecules, is interested in using the new material to protect components of airplanes and rockets from jet fuel.
Source: Science
Hinode reveals new insights about the origin of solar wind 
Images from NASA-funded telescopes aboard a Japanese satellite have shed new light about the sun's magnetic field and the origins of solar wind, which disrupts power grids, satellites and communications on Earth.
Data from the Hinode satellite shows that magnetic waves play a critical role in driving the solar wind into space. The solar wind is a stream of electrically charged gas that is propelled away from the sun in all directions at speeds of almost 1 million miles per hour. Better understanding of the solar wind may lead to more accurate prediction of damaging radiation waves before they reach satellites. Findings by American-led international teams of researchers appear in the the journal SCIENCE.
How the solar wind is formed and powered has been the subject of debate for decades. Powerful magnetic Alfvén waves in the electrically charged gas near the sun have always been a leading candidate as a force in the formation of solar wind since Alfvén waves in principle can transfer energy from the sun's surface up through its atmosphere, or corona, into the solar wind.
In the solar atmosphere, Alfvén waves are created when convective motions and sound waves push magnetic fields around, or when dynamic processes create electrical currents that allow the magnetic fields to change shape or reconnect.
"Until now, Alfvén waves have been impossible to observe because of limited resolution of available instruments," said Alexei Pevtsov, Hinode program scientist, NASA Headquarters, Washington. "With the help of Hinode, we are now able to see direct evidence of Alfvén waves, which will help us unravel the mystery of how the solar wind is powered."
Using Hinode's high resolution X-ray telescope, a team led by Jonathan Cirtain, a solar physicist at NASA's Marshall Space Flight Center, Huntsville, Ala., was able to peer low into the corona at the sun's poles and observe record numbers of X-ray jets. The jets are fountains of rapidly moving hot plasma. Previous research detected only a few jets daily.
With Hinode's higher sensitivity, Cirtain's team observed an average of 240 jets per day.
They conclude that magnetic reconnection, a process where two oppositely charged magnetic fields collide and release energy, is frequently occurring in the low solar corona. This interaction forms both Alfvén waves and the burst of energized plasma in X-ray jets.
"These observations show a clear relationship between magnetic reconnection and Alfvén wave formation in the X-ray jets." said Cirtain. "The large number of jets, coupled with the high speeds of the outflowing plasma, lends further credence to the idea that X-ray jets are a driving force in the creation of the fast solar wind."
Another research team led by Bart De Pontieu, a solar physicist at Lockheed Martin's Solar and Astrophysics Laboratory, Palo Alto, Calif., focused on the sun's chromosphere, the region sandwiched between the solar surface and its corona. Using extremely high-resolution images from Hinode's Solar Optical Telescope, De Pontieu's team found that the chromosphere is riddled with Alfvén waves. When the waves leak into the corona, they are strong enough to power the solar wind.
"We find that most of these Alfvén waves have periods of several minutes, much longer than many theoretical models have assumed in the past," says De Pontieu. Comparisons with advanced computer simulations from the University of Oslo, Norway, indicate that reconnection is not the only source of the Alfvén waves. "The simulations imply that many of the waves occur when the sun's magnetic field is jostled around by convective motions and sound waves in the low atmosphere," continued De Pontieu.
Source: Science
50 gigawatts of electrical power could be released by damming the Red Sea
Damming the Red Sea could solve the growing energy demands of millions of people in the Middle East and alleviate some of the region's tensions pertaining to oil supplies through hydroelectric power. Equally, such a massive engineering project may cause untold ecological harm and displace countless people from their homes.
In the Inderscience publication International Journal of Global Environmental Issues, Roelof Dirk Schuiling of Utrecht University in The Netherlands and his colleagues discuss the costs and benefits of one of the potentially most ambitious engineering projects ever.
Present technology allows us to shift and shape the earth on a relatively large scale and to control lakes and reservoirs for hydroelectric power generation. In the near future, however, it might be possible to build dams large enough to separate a body of water as large as the Red Sea, from the world oceans. A similar macro-scale engineering project is already planned for the Strait of Hormuz at the entrance of the Persian Gulf. This seawater barrier will exploit the evaporative cycle and influx of seawater to generate vast quantities of electricity.
Geochemical engineer Schuiling suggests that a dam Bab-al-Mandab could be used to stem the inflow of seawater into the highly evaporative Red Sea with the potential of generating 50 gigawatts of power. By comparison, the Palo Verde nuclear power plant, the largest nuclear station in the US has an output of just 3.2 gigawatts.
"Such a project will dramatically affect the region’s economy, political situation and ecology, and their effects may be felt well beyond the physical and political limits of the project," says Schuiling.
Schuiling and his colleagues point out that the cost and timescales involved in creating such a hydroelectric facility are way beyond normal economical considerations. It is inevitable that such a macro-engineering project will cause massive devastation of existing ecologies. However, it will also provide enormous reductions in greenhouse gas emissions as well as offering a viable, sustainable alternative to fossil fuels for future generations. The ethical and environmental dilemmas are on an international scale, while the impact on ecology, tourism, fisheries, transport and other areas could have effects globally.
The researchers point out that the precautionary principle cannot be applied in making a decision regarding the damming of the Red Sea. "If the countries around the Red Sea decide in favor of the macro-project, it is their responsibility to limit the negative consequences as much as possible," they conclude.
Source: International Journal of Global Environmental Issues
A new study, which appears today in the online edition of the European Heart Journal, has found strong evidence that recent respiratory infections increase the risk of heart attacks and strokes, both of which are more common in the winter.
It has for some years been recognised, using information from death certificates, that there is an excess of deaths from coronary heart disease (CHD) and stroke during the winter months, over and above those directly attributable to deaths from respiratory disease. More direct evidence has been necessary.
The authors of this study applied to the British Heart Foundation for funding to enable them to undertake further research to confirm or refute the findings of previous studies based on information from general practice which showed that respiratory infections were a strong risk factor for stroke.
The group, led by Tim Clayton and Tom Meade of the London School of Hygiene & Tropical Medicine’s Medical Statistics Unit, carried out a clinical case-control study in a general practice database, the IMS Disease Analyzer Mediplus database (IMS), which is used widely in epidemiological research. It contains details of some two million patients registered with approximately 500 GPs.
They found a doubling of risk of both heart attack and stroke in the week following respiratory infection, which reduced over time so that there was little excess risk beyond one month. Risk did not depend on age or gender and for heart attack was seen at every level of preceding risk, whether this had been low or high. There was also some evidence of an association between recent urinary tract infection and subsequent heart attack or stroke.
The researchers say that the benefit of reducing respiratory infection, either through ensuring high immunisation rates or by treating and preventing infection, may be substantial.
Tim Clayton comments: ‘These data add to the growing body of evidence linking respiratory infection with subsequent risk of cardiovascular events. However the absolute risk of such an event to an individual with respiratory infection remains low’.
Dr. Mike Knapton, Director of Prevention and Care at the British Heart Foundation, which funded the study, says: ‘We recommend that anyone with heart disease has the flu jab. Influenza is a serious infection, particularly in patients with heart disease such as heart failure, and it could even trigger a heart attack.
‘’Flu is a potential killer and heart patients are offered the flu jab for free, no matter what their age. We strongly recommend they take up the offer to give themselves protection against the flu’.
Source: European Heart Journal
Switzerland launches its largest research initiative ever in order to learn the language of lifeAfter decoding the genomes of various plants, animals and microorganisms, Systems Biology is regarded as the next major step that will drive biological research. Current technologies allow biologists to spell all the letters in the genetic material, however, they offer very little in the way of deciphering this complex code. Pharma- and biotechnology companies hope that Systems Biology will give them new tools for use in drug discovery and development.
Systems Biology is expensive, and requires the development and maintenance of elaborate technological platforms. Such platforms could not be financed by a single university or research instition individually. In addition good Systems Biology relies on the successful interaction of scientists from multiple disciplines including Biology, Chemistry, Mathematics, Computer Science, and Engineering.
After careful consideration of all of these issues, Swiss universities and research institutes decided to pool their knowledge and resources in a single research consortium called SystemsX.ch. The Universities of Basle, Berne, Lausanne, Fribourg, Geneva, and Zurich, the Paul Scherrer Institute, Friedrich Miescher Institute, and the Swiss Institute for Bioinformatics teamed up with the two Federal Institutes of Technology in Zurich and Lausanne to support this research initiative.
In its 2007 fall session, the Swiss parliament allocated 200 million Swiss Francs (CHF) for research in the area of Systems Biology from 2008-2011 (subject to yearly budget decisions). CHF 100 million will flow into Systems Biology research projects at the universities and other significant Swiss research institutions, which are partners of SystemsX.ch. However, monies will only be distributed to those partner institutions if they commit an equal amount to the research project in question. This means the federal government is requiring that an additional CHF 100 million come from the individual partners of SystemsX.ch. On top of that, parliament approved a CHF 100 million budget for the continued development of the Systems Biology relevant ETH Zurich Department for Biosystems Science and Engineering located in Basel.
Assuming universities and higher education institutions continue to apply for and obtain other grants to support their research activities (i.e. via the Swiss National Science Foundation and EU grants) and keep up their cooperation with industry partners, we can expect about CHF 400 million to flow into Systems Biology research from 2008-2011. A financial commitment of this scale for a specified research area is unprecedented in Switzerland. Concurrently, SystemsX.ch represents the largest thematically defined research initiative in recent (Swiss) history.
In the international arena, this effort is by no means unsubstantial. Since 2004 Great Britain has invested £88 million (CHF 214 million) into Systems Biology research. In Germany the federal government plans to spend about € 37 million per year (CHF 62 million) on Systems Biology from 2008-2011. This leaves the Swiss investment at the top of its class when spending is considered as an amount per population size.
Application deadline is end of 2007
All applications must be submitted by the end of the year. So far, the management office counts eighteen project ideas with intension of becoming research projects funded by SystemsX.ch. Projects in Zurich, Basle, and Lausanne, which are currently still being funded with monies from previous Systems Biology grants from the fusion partners of SystemsX.ch must also reapply for funding under the new scheme. Ralph Eichler, Chairman of the Board of Directors for SystemX.ch and ETH Zurich president says, «The scope and volume of individual projects should be in the range of CHF 1-5 million per year». In addition to this rather large ‘Research Technology and Development’ (RTD) projects, SystemsX.ch will fund about 40 «Interdisciplinary PhD» projects (IPhD) and 40 «Interdisciplinary Pilot Projects» (IPP). The IPPs should help seed interdisciplinary interactions among researchers from various academic backgrounds and institutions by allowing them to collaborate on an exciting and high risk project for a year.
The Swiss National Science Foundation (SNSF) has been mandated to supervise the scientific quality of SystemsX.ch projects. A special SNSF panel has been created for the evaluation, and periodical review of all the applications for RTD and IPhD projects. In addition to its six Swiss National Science Council members, this panel will contain internationally recognized experts from various disciplines crucial to Systems Biology. It is the first time the SNSF has agreed to be responsible for the quality control of a large research initiative, which it is not directly funding. This represents another important novelty being launched under the SystemsX.ch initiative.
All strategic and operational business decisions and transaction, including the administration and distribution of the SNSF-approved grants, will be left to SystemsX.ch. SystemsX.ch is operationally controlled by a Scientific Executive Board which is chaired by ETH Zurich Prof. Ruedi Aebersold. The Board of Directors (BoD) functions as the strategic organ of the organization. The BoD is made up of all the presidents, rectors, and directors of the SystemsX.ch member institutions plus two guests to represent the interests of industry, namely from Roche and Novartis.
Source: SystemX
Reducing salt intake by 15% and implementing key elements of WHO's tobacco control framework would avert millions of chronic disease related deaths for as little as an average US$0.36 per person per year. These are the conclusions of Dr Perviz Asaria, Kings Fund London, UK and his colleagues.
In their analysis, the authors studies 23 countries worldwide that carry 80% of the burden of chronic disease for low-income and middle-income countries. Two meta-analyses have shown that reducing salt intake in people with or without high blood pressure can reduce blood pressure by small but important amounts. In these countries, salt is used to preserve meat and fish, in seasoning and sauces, and at the table. Simple changes in diet, such as avoiding salty foods and not adding it at the table, can reduce sodium intake by 3-4.5g per day, around 30% of the average intake. Lowering salt content of, eg, soy sauce is also feasible, as is salt substitution.
The authors modelled the effect of a 15% reduction in salt consumption in the 23 countries, which would be achieved by voluntary reductions in salt content of processed foods and condiments by manufacturers, plus a sustained mass-media campaign aimed to encourage dietary change within households and communities. This strategy could avert 8.5 million deaths between 2006-2015.
For tobacco control, the authors looked at implementing four parts of the WHO Framework Convention on Tobacco Control (FCTC) increased taxes on tobacco to reduce smoking prevalence, enforcement of smoke-free workplaces, tobacco packaging and labelling restrictions combined with public awareness campaigns on health-risks of smoking, and finally a comprehensive ban on tobacco advertising, promotion, and sponsorship. Such interventions would reduce smoking prevalence by an estimated 20.8% in the 23 countries studied, thereby averting 5.5 million deaths from chronic diseases related to smoking -- ie, cardiovascular diseases, respiratory diseases, and cancers.
Combining both salt reduction and tobacco control figures would give an adjusted total of 13.8 million chronic disease related deaths averted. Most of the deaths averted (75.8%) would be from cardiovascular diseases, followed by deaths from respiratory disease (15.4%), and cancers (8.7%). More than half (58.7%) of deaths averted would be in men, due to their higher/longer exposures to tobacco in these countries. Deaths averted in men older and younger than 70 years would be about equal, whereas 71% of deaths averted in women would be in those aged over 70 years, reflecting lower tobacco exposures and later onset of cardiovascular mortality in women and the greater benefit of salt reduction in older age-groups who have higher baseline blood pressures.
Whilst actual numbers of deaths averted were highest in China and India due to sheer population size, the highest reductions in mortality rates per 100000 population over 30 years were in Russia (166), Poland (160), and Ukraine (153), reflecting the very high rates of cardiovascular disease in this populations, their high baseline blood pressures and exposure to tobacco. Salt interventions alone also had the greatest effect in these countries, while tobacco control alone had the highest effect in Poland, Vietnam, China, and Indonesia. The total averted deaths in the 23 countries would represent 60% of the global goal** for reduction of chronic disease for these countries, and 38% of the worldwide global goal.
The cost of implementing the strategy would range from US$0.14 to $0.38 per person per year in low-income and lower-middle income countries, and from $0.52 to $1.04 per person per year in upper-middle income countries. The average across the 23 countries was $0.36 per person per year, which on average was equivalent to 0.5% of government health spending in the 23 countries. However this proportion was 4.7% in the nine low-income countries studied. Most of the total cost, between 67-80%, would be to implement tobacco control, with the rest coming from salt restriction implementation.
The authors conclude: "Analysis of the global goal presented in the first paper of this Series suggests that [people in whom deaths are averted] might survive for 18 years on average. A small number of population-based interventions, which could be implemented without great cost or the need for structural change to the health system, especially in the 20 out of 23 countries that are signatories to the FCTC, could make a major contribution to the goal of reducing rates of death from chronic diseases by an additional 2% per year."
Source: Lancet
A new study by a Penn State College of Medicine research team found that honey may offer parents an effective and safe alternative than over the counter children's cough medicines. 
The study found that a small dose of buckwheat honey given before bedtime provided better relief of nighttime cough and sleep difficulty in children than no treatment or dextromethorphan (DM), a cough suppressant found in many over-the-counter cold medications.
Honey did a better job reducing the severity, frequency and bothersome nature of nighttime cough from upper respiratory infection than DM or no treatment. Honey also showed a positive effect on the sleep quality of both the coughing child and the child's parents. DM was not significantly better at alleviating symptoms than no treatment.
These findings are especially notable since an FDA advisory board recently recommended that over-the-counter cough and cold medicines not be given to children less than 6 years old because of their lack of effectiveness and potential for side effects. The results are published by Penn State College of Medicine researchers, led by Ian Paul in this month's Archives of Pediatrics and Adolescent Medicine.
In a previous study published in 2004, Paul and colleagues showed that neither DM nor diphenhydramine, another common component of cold medications, performed better than a placebo at reducing nighttime cough or improving sleep quality. However, honey has been used for centuries in some cultures to treat upper respiratory infection symptoms like cough, and is considered to be safe for children over 12 months old. Honey has well-established antioxidant and antimicrobial effects, which could explain its contributions to wound healing. Honey also soothes on contact, which may help explain its effect on cough as suggested by the World Health Organization.
In the latest study, the researchers enrolled 105 children between the ages of 2 and 18 at a single university-affiliated physician practice site. On the first night of the study, children received no treatment. Parents answered five questions about their child's cough and sleep quality as well as about their own sleep quality. On the second night, children received either honey, artificial honey-flavored DM or no treatment about a half hour prior to going to bed. Parents answered the same five questions the following morning.
The randomized study was partially double-blinded: Medical staff did not know what treatment each participating family received when distributing their sealed syringe-containing envelope. Parents of children who received honey or artificial honey-flavored DM in a measured syringe were blinded to their treatment group. Parents of children in the no treatment group received an empty syringe, and therefore were aware of their child's treatment group.
Across the board, parents rated honey as significantly better than DM or no treatment for symptomatic relief of their child's nighttime cough and sleep difficulty. In a few cases, parents did report mild side effects with the honey treatment, such as hyperactivity.
"Our study adds to the growing literature questioning the use of DM in children, but it also offers a legitimate and safe alternative for physicians and parents," said Paul, a pediatrician, researcher and associate professor of pediatrics at Penn State College of Medicine and Penn State Children's Hospital. "Additional studies should certainly be considered, but we hope that medical professionals will consider the positive potential of honey as a treatment given the lack of proven efficacy, expense, and potential for adverse effects associated with the use of DM."
Potentially dangerous effects of DM in young children include dystonic reactions, severe involuntary muscle contractions and spasms. Further, DM is a commonly used as a drug of abuse by adolescents.
Cough is the reason for nearly three percent of all outpatient visits in the United States, more than any other symptom. It is particularly bothersome at night because it disrupts sleep. Consumers spend billions of dollars each year on OTC cough and cold medications despite little evidence that these drugs provide significant relief.
Source: Archives of Pediatrics and Adolescent Medicine
Life may have begun in the protected spaces inside of layers of the mineral mica, in ancient oceans, according to a new hypothesis.
The hypothesis was developed by Helen Hansma, a research scientist with the University of California, Santa Barbara and a program director at the National Science Foundation. Hansma presented her findings at the annual meeting of the American Society for Cell Biology in Washington, D.C.
The Hansma mica hypothesis proposes that the narrow confined spaces between the thin layers of mica could have provided exactly the right conditions for the rise of the first biomolecules –– effectively creating cells without membranes. The separation of the layers would have also provided the isolation needed for Darwinian evolution.
“Some think that the first biomolecules were simple proteins, some think they were RNA, or ribonucleic acid,” said Hansma. “Both proteins and RNA could have formed in between the mica sheets.”
RNA plays an important part in translating the genetic code, and is composed of nitrogenous bases, sugar, and phosphates. RNA and many proteins and lipids in our cells have negative charges like mica. RNA’s phosphate groups are spaced one half nanometer apart, just like the negative charges on mica.
Mica layers are held together by potassium. The concentration of potassium inside the mica is very similar to the concentration of potassium in our cells. And the seawater that bathed the mica is rich in sodium, just like our blood.
The heating and cooling of the day to night cycle would have caused the mica sheets to move up and down, and waves would have provided a mechanical energy source as well, according to the new model. Both forms of movement would have caused the forming and breaking of chemical bonds necessary for the earliest biochemistry.
Thus the mica layers could have provided the support, shelter, and an energy source for the development of precellular life, while leaving artifacts in the structure of living things today.
Besides providing a more plausible hypothesis than the prebiotic oceanic “soup” model, Hansma said her new hypothesis also explains more than the so-called “pizza” hypothesis. That model proposes that biomolecules originated on the surfaces of minerals from the Earth’s crust. The “pizza” hypothesis cannot explain how the earliest biomolecules obtained the right amount of water to form stable biopolymers.
A biophysicist, Hansma has worked with mica for decades beginning with her work in biological Atomic Force Microscopy (AFM) in the late 1980s. “We put our samples on mica, because it is so atomically flat, so flat that we can see even bare DNA molecules as little ridges on the mica surface,” said Hansma. “The layered mineral is made of sheets so thin (one nanometer) that there are a million of them in a millimeter-thick sheet of mica.”
Hansma came upon her idea one day last spring when she was splitting some mica under her dissecting microscope. She had collected the specimens in a mica mine in Connecticut. The mica was covered with organic material.
“As I was looking at the organic crud on the mica, it occurred to me that this would be a good place for life to originate –– between these sheets that can move up and down in response to water currents which would have provided the mechanical energy for making and breaking bonds,” said Hansma.
She summed up her hypothesis of the origin of life by saying, “I picture all the molecules of early life evolving and rearranging among mica sheets in a communal fashion for eons before budding off with cell membranes and spreading out to populate the world.” Source: American Society for Cell Biology
Early flavor learning promotes acceptance of healthy foodsMoms, want your baby to learn to like fruits and vegetables? According to new research from the Monell Center, if you’re breast feeding, you can provide baby with a good start by eating them yourself. And, offer your baby plenty of opportunities to taste fruits and vegetables as s/he makes the transition to solid foods by giving repeated feeding exposures to these healthy foods — regardless of whether you’re breast feeding or using formula.
“Vegetable and fruit consumption is linked to lower risks of obesity and certain cancers,” says senior author Julie A. Mennella. “The best predictor of how much fruits and vegetables children eat is whether they like the tastes of these foods. If we can get babies to learn to like these tastes, we can get them off to an early start of healthy eating.”
The study, designed to test the influence of early sensory experiences on the development of healthy eating patterns, is published in the December 2007 issue of the journal Pediatrics.
Mennella and co-author Catherine A. Forestell studied 45 infants, 20 of whom were breastfed. The infants, who were between the ages of four and eight months and unaccustomed to eating solids other than cereal, were randomly assigned to one of two groups. One group was fed green beans for eight consecutive days; the other was given green beans and then peaches over the same period. Acceptance of both foods was assessed before and after the repeated exposure period.
The results revealed that breast-feeding confers an advantage for baby’s acceptance of foods during weaning — but only if the mother regularly eats those foods. During their first exposure to peaches, breast-fed infants ate more and for a longer period of time, compared to formula-fed infants. Questionnaires revealed that mothers of breast-fed infants ate more fruits than did formula-feeding mothers, suggesting that the enhanced peach acceptance of their infants might be attributed to increased exposure to fruit flavors through breast milk.
However, both groups of mothers reported eating green beans and green vegetables infrequently, at levels below current recommendations. Accordingly, there was no difference in the amount of green beans eaten by breast-fed and formula-fed infants the first time the vegetables were offered.
“It’s a beautiful system,” says Mennella. “Flavors from the mother’s diet are transmitted through amniotic fluid and mother’s milk. So, a baby learns to like a food’s taste when the mother eats that food on a regular basis.”
In both groups, repeated opportunities to taste green beans over eight days enhanced acceptance of the vegetable, increasing intake by almost three-fold. “Babies are born with a dislike for bitter tastes,” explains Mennella. “If mothers want their babies to learn to like to eat vegetables, especially green vegetables, they need to provide them with opportunities to taste these foods.”
The researchers also found that babies’ facial expressions did not always match their willingness to continue feeding, noting that infants innately display facial expressions of distaste to certain flavors. They urge caregivers to provide their infants with repeated opportunities to taste fruits and vegetables, focusing on the infant’s willingness to eat the food instead of on their negative facial expressions during eating.
Source: Pediatrics
The compound sulforaphane whose natural precursors are found at high levels in broccoli and other cruciferous vegetables has been hailed for its chemopreventive powers against cancer. Now sulforaphane has demonstrated new skills in treating a genetic skin blistering disorder called epidermolysis bullosa simplex (EBS), Pierre Coulombe and colleagues at the Johns Hopkins University School of Medicine in Baltimore report at the American Society for Cell Biology 47th Annual Meeting.
EBS is a rare but devastating inherited condition in which fluid-filled lesions called bullae appear at sites of frictional trauma to the skin. Unfortunately, treatment options for EBS are limited and palliative in nature. Much work remains to be done before sulforaphane can be tested clinically with EBS patients, but Coulombe notes that extracts from broccoli sprouts rich in sulforaphane have already been shown to be safe for use in human skin.
In EBS patients, the bottom layer of the epidermis, which is made of cells called keratinocytes, is unusually fragile and ruptures readily. Molecularly, most cases of EBS result from mutations in genes that produce the proteins keratin 5 (K5) and keratin 14 (K14). These proteins co-polymerize to form the intermediate filament cytoskeleton in basal keratinocytes. Since the discovery in 1991 that EBS is a keratin-based disease, more than 40 additional disorders affecting a broad range of tissues have been traced to defects in genes that encode intermediate filament proteins.
Coulombe and colleagues turned to sulforaphane in their search for a chemical activator that would induce the production of missing keratins in basal epidermis. There are 54 “conserved” keratin proteins in mammals -- meaning that evolution favored their survival. Many of these keratins are closely related in their genetic sequences and their properties and by their distribution within epithelial tissues. Coulombe reasoned that such a situation breeds “functional redundancy,” meaning that the genetic loss of one keratin could be partially rescued by the overlapping functions of a keratin cousin.
Could this partial redundancy serve as the basis for therapy in EBS and related conditions? Coulombe was guided by prior evidence that partial redundancy was at work. In EBS patients, skin blisters heal without scarring, correlating with an induction in the expression of the protein K6, to which K5 is related, and of K17 and K16, to which K14 is related. In transgenic mouse models, these keratins are indeed partially redundant in their ability to provide structural support in skin keratinocytes.
Sulforaphane was originally identified by Johns Hopkins colleague, Paul Talalay, as the chemical entity in cruciferous vegetables responsible for its anti-cancer properties. As originally reported in the August 2007 issue of PNAS, the researchers found that exposing keratinocytes to sulforaphane caused the selective induction of keratins 16 and 17. Moving to an EBS mouse model with a K14 deficiency, they found that treatment with sulforaphane significantly reduced epidermal blistering while it was ineffective for a K5 deficient mouse.
Source: American Society for Cell biology
Coffee is an effective countermeasure to sleepiness for both young and middle-aged people. However, napping is more efficient in young than in middle-aged people, according to a study published in the December 1 issue of the journal SLEEP.
Patricia Sagaspe of the Clinique du Sommeil at CHU Pellegrin in Bordeau, France, studied 24 people, 12 young (between 20-25 years of age) and 12 middle-aged (between 40-50 years of age). Participants first drove 125 highway miles in the daylight, between 6:00 and 7:30 p.m. Then, in a test of the effects of coffee and napping on night-time driving, participants drove another 125 miles between 2:00 and 3:30 a.m. after having a cup of coffee with 200 mg of caffeine, a placebo (a cup of decaffeinated coffee with 15 mg of caffeine) or a 30-minute nap.
Inappropriate line crossings, self-perceived fatigue and sleepiness and polysomnographic recordings were analyzed in the study. According to the results, compared to daytime, after a placebo, the number of inappropriate line crossings was significantly increased. Compared with a placebo, both coffee and napping reduced the risk of inappropriate line crossings in young and middle-aged participants. A significant interaction between age and condition showed that napping led to fewer inappropriate line crossings in younger than in middle-aged participants. During napping, young participants slept more and had more delta sleep than middle-aged participants.
Self-perceived sleepiness and fatigue did not differ between age groups, but coffee improved sleepiness, whereas napping did not. The potential effect of age on response to sleepiness countermeasures should be considered in populations exposed to extended wakefulness,� said Dr. Sagaspe. According to their age or individual physiology, subjects should implement their best countermeasures to sleepiness at the wheel.On average, most adults need seven to eight hours of sleep each night to feel alert and well-rested.
The American Academy of Sleep Medicine (AASM) offers the following tips on how to get a good night sleep:
1. Avoid foods or drinks that contain caffeine, as well as any medicine that has a stimulant, prior to bedtime.
2. Follow a consistent bedtime routine.
3. Establish a relaxing setting at bedtime.
4. Get a full night sleep every night.
5. Do not go to bed hungry, but donï eat a big meal before bedtime either.
6. Avoid any rigorous exercise within six hours of your bedtime.
7. Make your bedroom quiet, dark and a little bit cool.
8. Get up at the same time every morning.
Those who believe they have a sleep disorder should consult with their primary care physician or a sleep specialist.
Source: SLEEP
Hospital staff nurses who work extended hours, work at night, struggle to remain awake at work, or obtain less sleep are more likely to experience a drowsy driving episode, according to a study published in the December 1 issue of the journal SLEEP.
The study, authored by Linda D. Scott, PhD, of Grand Valley State University in Grand Rapids, Mich., focused on data that were collected from 895 full-time hospital staff nurses, who completed logbooks on a daily basis for four weeks providing information concerning work hours, sleep duration, drowsy and sleep episodes at work, and drowsy driving occurrences.
According to the results, almost 67 percent of the nurses reported at least one episode of drowsy driving, and three percent reported experiencing drowsy driving following every shift worked. On average, nurses reported experiencing an episode of drowsy driving one out of every four shifts they worked.
Two-hundred eighty-one episodes of motor vehicle crashes/near-motor vehicle crashes were reported during the study period. The majority of these incidents occurred following shifts that exceeded 12.5 hours in duration. The likelihood of a motor vehicle crash/near-motor vehicle crash significantly increased with longer shift durations. The risk for a motor vehicle crash/near-motor vehicle crash almost doubled when driving following shifts that exceeded 12.5 hours.
The risk for a drowsy driving episode doubled when nurses worked 12.5 or more consecutive hours. Working at night also significantly increased the risk for drowsy driving incident. In fact, 79.5 percent of the nurses who worked only night shifts reported at least one episode of drowsy driving.
Almost two-thirds of the nurses reported struggling to stay awake at work at least once during the study period, and 16.9 percent of the nurses actually fell asleep at least one during their work shift. Nurses who struggled to stay awake at work were significantly more likely to report struggling to stay awake driving home after work. In particular, the likelihood of a drowsy driving incident was tripled when nurses experienced episodes of drowsiness at work. The risk for a drowsy driving episode was also increased when nurses reported falling asleep on duty.
Although research on the effects of chronic sleep restriction has revealed that most adults require at least seven to eight hours of sleep each night to avoid developing chronic sleep debt with its accompanying performance deficits, the hospital staff nurses in this study frequently obtained less sleep than this critical threshold. Only 20.8 percent of the participants reported obtaining at least six hours of sleep prior to every shift they worked. The risk for a drowsy driving episode increased by nine percent for each hour of sleep lost.
“Given the large number of nurses who reported struggling to stay awake when driving home from work and the frequency with which nurses reported drowsy driving, greater attention should be paid to increasing nurse awareness of the risks and to implementing strategies to prevent drowsy driving episodes to ensure public safety,” said Dr. Scott. “Without mitigation, fatigued nurses will continue to put the public and themselves at risk.”
In a sense, drowsy driving can be comparable to driving under the influence, as sleepiness results in a slower reaction time, decreased awareness, impaired judgment and an increased risk of getting involved in an accident, resulting in unnecessary deaths or injuries to innocent people. Nearly nine out of every ten police officers responding to an AAA Foundation for Traffic Safety Internet survey reported they had stopped a driver who they believed was drunk, but turned out to be drowsy. The survey was coordinated with the National Highway Traffic Safety Administration (NHTSA).
Drowsy driving can be prevented by becoming educated on the importance of sleep and the risks involved with taking the wheel while feeling fatigued.
There are two main causes of drowsy driving:
Sleep restriction
Persons getting less than the recommended seven-to-eight hours of sleep each night are more likely to feel tired the following day, which can ultimately affect their cognizance behind the wheel. Not getting enough sleep on a consistent basis can create “sleep debt” and lead to chronic sleepiness over time. While some factors, including working at a job that requires long hours and familial responsibilities, are beyond a person’s control, other reasons for sleep restriction represent a lifestyle choice. This includes sleeping less to have more time to work, study, socialize or participate in other activities.
Sleep fragmentation
Sleep fragmentation causes an inadequate amount of sleep and can negatively affect a person’s functioning during the daytime. Sleep fragmentation can have internal and external causes. The primary internal cause is sickness, including untreated sleep disorders. External factors that can prevent a person’s ability to have a full, refreshing night of sleep include noise, children, bright lights and a restless bed partner.
Drowsy driving is the direct cause of approximately 100,000 police-reported crashes annually, resulting in an estimated 1,550 deaths, 71,000 injuries and $12.5 billion in monetary losses, according to the NHTSA. On average, most adults need seven to eight hours of sleep each night to feel alert and well-rested.
According to the American Academy of Sleep Medicine (AASM), people can avoid becoming drowsy while driving by following these tips:
1.Get enough sleep
2. AASM recommends that adults get seven-to-eight hours of sleep each night in order to maintain good health and optimum performance.
3. Take breaks while driving
4. If you become drowsy while driving, pull off to a rest area and take a short nap, preferably 15-20 minutes in length.
5. Consume caffeine
6. Caffeine improves alertness in people who are fatigued.
7. Do not drink alcohol
8. Alcohol can further impair a person’s ability to stay awake and make good decisions. Taking the wheel after having just one glass of alcohol can affect your level of fatigue while driving.
9. Do not drive late at night
10. Avoid driving after midnight, which is a natural period of sleepiness
Surce: Sleep
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