QuoteReplyTopic: Science and Nature News Redux Posted: 25-Mar-2012 at 14:24
Getting the Dirt On Immunity: Scientists Show Evidence for Hygiene Hypothesis
This concept of exposing people to germs at an early age (i.e., childhood) to build immunity is known as the hygiene hypothesis.
Previous human studies have suggested that early life exposure to microbes (i.e., germs) is an important determinant of adulthood sensitivity to allergic and autoimmune diseases such as hay fever, asthma and inflammatory bowel disease.
This concept of exposing people to germs at an early age (i.e., childhood) to build immunity is known as the hygiene hypothesis.
Medical professionals have suggested that the hygiene hypothesis explains the global increase of allergic and autoimmune diseases in urban settings. It has also been suggested that the hypothesis explains the changes that have occurred in society and environmental exposures, such as giving antibiotics early in life.
However, neither biologic support nor a mechanistic basis for the hypothesis has been directly demonstrated. Until now.
Researchers at Brigham and Women's Hospital (BWH) have conducted a study that provides evidence supporting the hygiene hypothesis, as well as a potential mechanism by which it might occur.
The study was published online in the journal Science on the Science Express Web site on March 22, 2012.
The researchers studied the immune system of mice lacking bacteria or any other microbes ("germ-free mice") and compared them to mice living in a normal environment with microbes.
They found that germ-free mice had exaggerated inflammation of the lungs and colon resembling asthma and colitis, respectively. This was caused by the hyperactivity of a unique class of T cells (immune cells) that had been previously linked to these disorders in both mice and humans.
Most importantly, the researchers discovered that exposing the germ-free mice to microbes during their first weeks of life, but not when exposed later in adult life, led to a normalized immune system and prevention of diseases.
Moreover, the protection provided by early-life exposure to microbes was long-lasting, as predicted by the hygiene hypothesis.......
Magnetic Field Researchers Target 100-Tesla Goal: Previous World Record Shattered During Six-Experiment Pulse
The 1,200-megajoule motor generator that powers the magnetic pulse.
Researchers at Los Alamos National Laboratory's biggest magnet facility have just met the grand challenge of producing magnetic fields in excess of 100 tesla while conducting six different experiments. The hundred-tesla level is roughly equivalent to 2 million times Earth's magnetic field.
"This is our moon shot, we've worked toward this for a decade and a half," said Chuck Mielke, director of the Pulsed Field Facility at Los Alamos.
The team used the 100-tesla pulsed, multi-shot magnet, a combination of seven coils sets weighing nearly 18,000 pounds and powered by a massive 1,200-megajoule motor generator. There are higher magnetic fields produced elsewhere, but the magnets that create such fields blow themselves to bits in the process. The system at Los Alamos is instead designed to work nondestructively, in the intense 100-tesla realm, on a regular basis. The Los Alamos facility is one of three campuses forming the National High Magnetic Field Laboratory (NHMFL).
Today's 100.75-tesla performance produced research results for scientific teams from Rutgers University, École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), McMaster University, University of Puerto Rico, University of Minnesota, Cambridge University, University of British Columbia, and Oxford University. The science that we expect to come out varies with the experiment, but can be summarized as:
Quantum Phase transitions and new ultra high field magnetic states
Electronic Structure determination
Topologically protected states of matter
"Congratulations to the Los Alamos team and our collaborators," said LANL Director Charlie McMillan. "Their innovations and creativity are not only breaking barriers in science, but solving national problems in the process."........
Composite image: the left side is a laser-produced shock wave whilst the right is a simulation of a collapsing shock wave arising during the pre-galactic phase.
Scientists have used a laser to create magnetic fields similar to those thought to be involved in the formation of the first galaxies; findings that could help to solve the riddle of how the Universe got its magnetism.
Magnetic fields exist throughout galactic and intergalactic space, what is puzzling is how they were originally created and how they became so strong.
A team, led by Oxford University physicists, used a high-power laser to explode a rod of carbon, similar to pencil lead, in helium gas. The explosion was designed to mimic the cauldron of plasma -- an ionized gas containing free electrons and positive ions -- out of which the first galaxies formed.
The team found that within a microsecond of the explosion strong electron currents and magnetic fields formed around a shock wave. Astrophysicists took these results and scaled them through 22 orders-of-magnitude to find that their measurements matched the 'magnetic seeds' predicted by theoretical studies of galaxy formation.
A report of the research is published in a recent issue of the journal Nature.
'Our experiment recreates what was happening in the early Universe and shows how galactic magnetic fields might have first appeared,' said Dr Gianluca Gregori of Oxford University's Department of Physics, who led the work at Oxford. 'It opens up the exciting prospect that we will be able to explore the physics of the cosmos, stretching back billions of years, in a laser laboratory here on Earth.'
The results closely match theories which predict that tiny magnetic fields -- 'magnetic seeds' -- precede the formation of galaxies. These fields can be amplified by turbulent motions and can strongly affect the evolution of the galactic medium from its early stages.
Dr Gregori said: 'In the future, we plan to use the largest lasers in the world, such as the National Ignition Facility at the Lawrence Livermore National Laboratory in California (USA), to study the evolution of cosmic plasma.'
The experiments were conducted at the Laboratoire pour l'Utilisation de Lasers Intenses laser facility in France.
Brain Size May Determine Whether You Are Good at Keeping Friends
Friends. Researchers are suggesting that there is a link between the number of friends you have and the size of the region of the brain -- known as the orbital prefrontal cortex -- that is found just above the eyes.
Researchers are suggesting that there is a link between the number of friends you have and the size of the region of the brain -- known as the orbital prefrontal cortex -- that is found just above the eyes. A new study shows that this brain region is bigger in people who have a larger number of friendships.
Their study is published on 1 February 2012 in the journal, Proceedings of the Royal Society B.
The research was carried out as part of the British Academy Centenary 'Lucy to Language' project, led by Professor Robin Dunbar of the University of Oxford in a collaboration with Dr Joanne Powell and Dr Marta Garcia-Finana at Liverpool University, Dr Penny Lewis at Manchester University and Professor Neil Roberts at Edinburgh University.
The study suggests that we need to employ a set of cognitive skills to maintain a number of friends (and the keyword is 'friends' as opposed to just the total number of people we know). These skills are described by social scientists as 'mentalising' or 'mind-reading'- a capacity to understand what another person is thinking, which is crucial to our ability to handle our complex social world, including the ability to hold conversations with one another. This study, for the first time, suggests that our competency in these skills is determined by the size of key regions of our brains (in particular, the frontal lobe).
Professor Dunbar, from the Institute of Cognitive and Evolutionary Anthropology, explained: '"Mentalising" is where one individual is able to follow a natural hierarchy involving other individuals' mind states. For example, in the play 'Othello', Shakespeare manages to keep track of five separate mental states: he intended that his audience believes that Iago wants Othello to suppose that Desdemona loves Cassio [the italics signify the different mind states]. Being able to maintain five separate individuals' mental states is the natural upper limit for most adults.'.......
Graphene could help build a new generation of electronic devices, such as touch screens, solar panels and superfast computers.
Imagine a material that is just one atom thick, 300 times stronger than steel, harder than diamond, a fantastic conductor of heat and electricity and super-flexible to boot.
This might sound like the stuff of science fiction, but believe it or not, such a material already exists.
The name of this supermaterial is graphene and it’s one of the most exciting prospects in science today.
The researchers found a way to dampen external influences on the graphene, and could then observe electrons moving through their graphene three times faster than was previously possible.
This development could pave the way for a new generation of graphene-based devices including touch screens and solar panels.
More on the uses of graphene in a moment, but first: what is graphene?
Quite simply, graphene is a new structural form (or 'allotrope') of carbon – one of the most versatile elements in the universe. It was discovered in 2004 by Russian-born physicists Andre Geim and Konstantin Novoselov, who jointly received the 2010 Nobel Prize in Physics for their troubles.
Graphene is a single, flat layer of carbon atoms packed tightly into a two-dimensional honeycomb arrangement. The in-plane (two-dimensional) carbon-carbon bonds in graphene are the strongest bonds known to science. It is these bonds that give graphene its unbelievable mechanical strength and flexibility.
Graphene is essentially a single layer of graphite, the material found in pencil 'lead'. When you draw on paper with a pencil, weakly bound graphene sheets in the graphite spread over your paper like a pack of cards.
But because graphene is so thin – the thickness of a single carbon atom – it is extremely difficult to see. This is one of the reasons it took researchers so long to find graphene sheets among thicker stacks of graphite.
Despite being so thin, graphene is an excellent conductor of electricity. Electrons flow through graphene with almost zero electrical resistance. This unusual property, and the fact graphene is nearly invisible, makes it an ideal material for the transparent electrodes used in computer displays and solar cells.
While scientists have known about graphene since 2004, it was in 2010 that researchers from Samsung and Sungkyunkwan University took a critical step in developing the commercial applications of this material.
They developed a scalable fabrication method which enabled them to produce transparent and flexible graphene electrodes measuring 30 inches (76 cm) diagonally. This method enabled them to manufacture multi-layer electrode films and incorporate these into a fully functional touch-screen panel device capable of withstanding high strain.
As a result of this development, it mightn’t be too long before graphene is powering the displays on your favourite electronic gadgets.
One of the most promising aspects of graphene is its potential as a replacement to silicon in computer circuitry. Graphene conducts electricity faster (at room temperature) than any other material, it produces very little heat dissipation and it consumes less power than silicon – the building block of modern computing.
These characteristics could make graphene ideal as the basis for superior signal processing components in superfast computers and mobile technologies.
But there are still many obstacles that need to be overcome.
Probably the biggest barrier is the low 'on-off current ratio' of current, superfast graphenetransistors. Put another way, electrons in graphene are almost unstoppable and therefore very hard to control. As a result it is almost impossible to set graphene transistors to an 'off' state.
If graphene is to compete with existing silicon technology, this on-off current ratio will need to be improved. In other words, we’ll need to find a way to control electrical currents within graphene transistors so we can turn them 'off'.
Many researchers are currently working on this exact problem, trying to gain control over the disobedient charge carriers by opening a gap in graphene’s “electronic band” – the part of the material that conducts electricity.
Graphene can also be modified to take on different properties than are found in its normal form. For instance, researchers have:
Each of these modifications has potential technological applications.
Graphene sheets can also be incorporated in different composite materials, harnessing graphene’s extraordinary mechanical, thermal and electrical properties. These composite materials could lead to stronger and lighter car and airplane parts, better electrical batteries and electricity-conducting, super-tough textiles.
But perhaps one of the most surprising and unusual graphene discoveries relates to membranes made of graphene oxide – a chemical derivative of graphene.
When these membranes were used to seal a metal container, not even the smallest gas molecule, such as helium, could penetrate the membrane. But when the researchers tried the same with water, they found the water could pass through the graphene-oxide membrane with no problems.
Although the principle behind this unusual behaviour is not yet understood, it could one day be used in the selective removal of water or other filtration applications.
This surprising result shows how much we still have to learn about graphene. If current research and development is anything to go by, we’ll be hearing plenty more about this amazing material in the years to come.
Even women who ate chicken or pork but avoided red meat were twice as likely to be depressed or anxious. But don't go overboard - eating too much red meat is also related to mental health problems, the research found.
Deakin University health researchers have found that eating less than the recommended amount of red meat is related to depression and anxiety in women. Associate Professor Felice Jacka and colleagues from Deakin’s Barwon Psychiatric Research Unit based at Barwon Health investigated the relationship between the consumption of beef and lamb and the presence of depressive and anxiety disorders in more than 1000 women from the Geelong region. The results are published in the current edition of the journal Psychotherapy Psychosomatics.
“We had originally thought that red meat might not be good for mental health, as studies from other countries had found red meat consumption to be associated with physical health risks, but it turns out that it actually may be quite important,” Associate Professor Jacka said.
“When we looked at women consuming less than the recommended amount of red meat in our study, we found that they were twice as likely to have a diagnosed depressive or anxiety disorder as those consuming the recommended amount.
“Even when we took into account the overall healthiness of the women’s diets, as well as other factors such as their socioeconomic status, physical activity levels, smoking, weight and age, the relationship between low red meat intake and mental health remained.
“Interestingly, there was no relationship between other forms of protein, such as chicken, pork, fish or plant-based proteins, and mental health.
“Vegetarianism was not the explanation either. Only 19 women in the study were vegetarians, and the results were the same when they were excluded from the study analyses.”
Associate Professor Jacka said that it didn’t seem to be a good idea to eat too much red meat either.
“We found that regularly eating more than the recommended amount of red meat was also related to increased depression and anxiety,” she said.
Given the results of this study, Associate Professor Jacka believes following the recommended weekly intake of red meat could boost our mental health.
“We already know that the overall quality of your diet is important to mental health. But it seems that eating a moderate amount of lean red meat, which is roughly 3-4 small, palm-sized serves a week, may also be important,” she said.
Associate Professor Jacka also suggests sticking with grass fed meats whenever possible.
“We know that red meat in Australia is a healthy product as it contains high levels of nutrients, including the omega-3 fatty acids that are important to mental and physical health. This is because cattle and sheep in Australia are largely grass fed. In many other countries, the cattle are kept in feedlots and fed grains, rather than grass. This results in a much less healthy meat with more saturated fat and fewer healthy fats.”
In the future, windows could be sprayed with the newly developed carbon nanotube solar cells and used to generate electricity.
Imagine a world where the windows of high-rise office buildings are powerful energy producers, offering its inhabitants much more than some fresh air, light and a view. For the past four years a team of researchers from Flinders University has been working to make this dream a reality – and now the notion of solar-powered windows could be coming to a not too distant future near you.
As part of his just-completed PhD, Dr Mark Bissett from the School of Chemical and Physical Sciences has developed a revolutionary solar cell using carbon nanotubes.
A promising alternative to traditional silicon-based solar cells, carbon nanotubes are cheaper to make and more efficient to use than their energy-sapping, silicon counterparts.
“Solar power is actually the most expensive type of renewable energy – in fact the silicon solar cells we see on peoples’ roofs are very expensive to produce and they also use a lot of electricity to purify,” Dr Bissett said.
“The overall efficiency of silicon solar cells are about 10 per cent and even when they’re operating at optimal efficiency it could take eight to 15 years to make back the energy that it took to produce them in the first place because they’re produced using fossil fuels,” he said.
Dr Bissett said the new, low-cost carbon nanotubes are transparent, meaning they can be 'sprayed' onto windows without blocking light, and they are also flexible so they can be weaved into a range of materials including fabric – a concept that is already being explored by advertising companies.
While the amount of power generated by solar windows would not be enough to completely offset the energy consumption of a standard office building, Dr Bissett said they still had many financial and environmental advantages.
“In a new building, or one where the windows are being replaced anyway, adding transparent solar cells to the glass would be a relatively small cost since the cost of the glass, frames and installation would be the same with or without the solar component,” Dr Bissett said.
“It’s basically like tinting the windows except they’re able to produce electricity, and considering office buildings don’t have a lot of roof space for solar panels it makes sense to utilise the many windows they do have instead.”
Dr Bissett said the technology mimics photosynthesis, the process whereby plants obtain energy from the sun.
“A solar cell is created by taking two sheets of electrically conductive glass and sandwiching a layer of functionalised single-walled carbon nanotubes between the glass sheets,” he said.
“When light shines on the cell, electrons are generated within the carbon nanotubes and these can be used to power electrical devices.”
Although small prototypes have been developed in the lab, he said the next step would be to test the carbon cells on an 'industrial stage'.
If all goes to plan, the material could be on the market within 10 years.
“When we first started the research we had no idea if it would work because we were the first in the world to try it so it’s pretty exciting that we’ve proved the concept, and hopefully it will be commercially available in a few year’s time,” Dr Bissett said.
Dr Bissett is a winner of Flinders inaugural Best Student Paper Award, a now annual program which aims to recognise excellence in student research across the University.
Highly Flexible Despite Hard-Wiring: Even Slight Stimuli Change the Information Flow in the Brain
Images or cup? Due to the rapid reorganization of networks in the brain we perceive different elements of the image.
One cup or two faces? What we believe we see in one of the most famous optical illusions changes in a split second; and so does the path that the information takes in the brain. In a new theoretical study, scientists of the Max Planck Institute for Dynamics and Self-Organization, the Bernstein Center Göttingen and the German Primate Center now show how this is possible without changing the cellular links of the network. The direction of information flow changes, depending on the time pattern of communication between brain areas. This reorganisation can be triggered even by a slight stimulus, such as a scent or sound, at the right time.
The way that the different regions of the brain are connected with each other plays a significant role for information processing. This processing can be changed by the assembling and disassembling of nerve fibres joining distant brain circuits. But such events are much too slow to explain rapid changes in perception. From experimental studies it was known that the responsible actions must be at least two orders of magnitude faster. The Göttingen scientists now show for the first time that it is possible to change the information flow in a tightly interconnected network in a simple manner.
Many areas of the brain display a rhythmic nerve cell activity. "The interacting brain areas are like metronomes that tick at the same speed and in a distinct temporal pattern," says the physicist and principal investigator Demian Battaglia. The researchers were now able to demonstrate that this temporal pattern determines the information flow. "If one of the metronomes is affected, e.g. through an external stimulus, then it changes beat, ticking in an altered temporal pattern compared to the others. The other areas adapt to this new situation through self-organisation and start playing a different drum beat as well. It is therefore sufficient to impact one of the areas in the network to completely reorganize its functioning, as we have shown in our model," explains Battaglia.
The applied perturbation does not have to be particularly strong. "It is more important that the 'kick' occurs at exactly the right time of the rhythm," says Battaglia. This might play a significant role for perception processes: "When viewing a picture, we are trained to recognize faces as quickly as possible -- even if there aren't any," points out the Göttingen researcher. "But if we smell a fragrance reminiscent of wine, we immediately see the cup in the picture. This allows us to quickly adjust to things that we did not expect, changing the focus of our attention.".......
That's a great concept, although problematic I would think in one respect. Having to remove so much from the inside which might break when rolling down the road. Unless there's a suggestion that things are constructed in such a way as to not need so many of those things.
What a handsome figure of a dragon. No wonder I fall madly in love with the Alani Dragon now, the avatar, it's a gorgeous dragon picture.
High-Throughput Screening Finds Surprising Properties for Antioxidants: Some Compounds Can Damage DNA, but May Treat Cancer
Researchers have demonstrated that some antioxidants damage DNA and kill cells instead of protecting them. The findings also suggest that this surprising capability may be good for treating cancer, but may prove cautionary when using antioxidant-based medicines to treat other disorders, such as diabetes.
Antioxidants have long been thought to have anti-aging properties, primarily by protecting a person's genetic material from damaging chemicals. The story, however, now appears to be much more complicated.
National Institutes of Health researchers from two institutes and one center have demonstrated that some antioxidants damage DNA and kill cells instead of protecting them. The findings, published in theProceedings of the National Academy of Sciences on March 19, 2012, also suggest that this surprising capability may be good for treating cancer, but may prove cautionary when using antioxidant-based medicines to treat other disorders, such as diabetes.
"It's an unexpected discovery," says Kyungjae Myung, Ph.D., a senior investigator in the Genetics and Molecular Biology Branch of the National Human Genome Research Institute (NHGRI), and the senior author on the report. "It may have important clinical applications in treating people with cancer, especially if they have failed previous treatments."
Many people attempt to boost their levels of antioxidants by eating fruits and vegetables, nuts and grains, or by taking vitamins such as A, C, E and beta-carotene, among others. Some research suggests that antioxidants soak up compounds called free radicals produced by burning oxygen during normal respiration. Free radicals cause random chemical reactions that can damage cellular components, including DNA, leading to disease. By adding antioxidants to the diet, many people hope to slow down the process that some believe contributes to the normal process of aging.
Dr. Myung did not set out to challenge this anti-aging strategy, and the new findings may not fundamentally alter the approach; much more study will be needed. Instead, his lab studies DNA repair, the enzyme systems within a cell that fix mistakes and other damage that routinely accumulate in DNA as cells simply live and divide to make daughter cells. Researchers know that naturally occurring defects in DNA repair can lead to a number of disorders, including cancer.........
Humans Began Walking Upright to Carry Scarce Resources, Chimp Study Suggests
Most of us walk and carry items in our hands every day. These are seemingly simple activities that the majority of us don't question. Researchers have discovered that human bipedalism, or walking upright, may have originated millions of years ago as an adaptation to carrying scarce, high-quality resources.
Most of us walk and carry items in our hands every day. These are seemingly simple activities that the majority of us don't question. But an international team of researchers, including Brian Richmond at the George Washington University, have discovered that human bipedalism, or walking upright, may have originated millions of years ago as an adaptation to carrying scarce, high-quality resources. This latest research was published in this month's Current Biology.
The team of researchers from the U.S., England, Japan and Portugal investigated the behavior of modern-day chimpanzees as they competed for food resources, in an effort to understand what ecological settings would lead a large ape -- one that resembles the 6 million-year old ancestor we shared in common with living chimpanzees -- to walk on two legs.
"These chimpanzees provide a model of the ecological conditions under which our earliest ancestors might have begun walking on two legs," said Dr. Richmond, an author of the study and associate professor of anthropology at GW's Columbian College of Arts and Sciences. "Something as simple as carrying -- an activity we engage in every day -- may have, under the right conditions, led to upright walking and set our ancestors on a path apart from other apes that ultimately led to the origin of our kind."
The research findings suggest that chimpanzees switch to moving on two limbs instead of four in situations where they need to monopolize a resource, usually because it may not occur in plentiful supply in their habitat, making it hard for them to predict when they will see it again. Standing on two legs allows them to carry much more at one time because it frees up their hands. Over time, intense bursts of bipedal activity may have led to anatomical changes that in turn became the subject of natural selection where competition for food or other resources was strong.
Two studies were conducted by the team in Guinea. The first study was in Kyoto University's "outdoor laboratory" in a natural clearing in Bossou Forest. Researchers allowed the wild chimpanzees access to different combinations of two different types of nut -- the oil palm nut, which is naturally widely available, and the coula nut, which is not. The chimpanzees' behavior was monitored in three situations: (a) when only oil palm nuts were available, (b) when a small number of coula nuts was available, and (c) when coula nuts were the majority available resource.
When the rare coula nuts were available only in small numbers, the chimpanzees transported more at one time. Similarly, when coula nuts were the majority resource, the chimpanzees ignored the oil palm nuts altogether. The chimpanzees regarded the coula nuts as a more highly-prized resource and competed for them more intensely.........
New Theory On Size of Black Holes: Gas-Guzzling Black Holes Eat Two Courses at a Time
Image from a simulation when the inclination is 150 degrees with full 3D rendering.
Astronomers have put forward a new theory about why black holes become so hugely massive -- claiming some of them have no 'table manners', and tip their 'food' directly into their mouths, eating more than one course simultaneously.
Researchers from the UK and Australia investigated how some black holes grow so fast that they are billions of times heavier than the sun.
The team from the University of Leicester (UK) and Monash University in Australia sought to establish how black holes got so big so fast.
Professor Andrew King from the Department of Physics and Astronomy, University of Leicester, said: "Almost every galaxy has an enormously massive black hole in its center. Our own galaxy, the Milky Way, has one about four million times heavier than the sun. But some galaxies have black holes a thousand times heavier still. We know they grew very quickly after the Big Bang.''
"These hugely massive black holes were already full--grown when the universe was very young, less than a tenth of its present age."
Black holes grow by sucking in gas. This forms a disc around the hole and spirals in, but usually so slowly that the holes could not have grown to these huge masses in the entire age of the universe. `We needed a faster mechanism,' says Chris Nixon, also at Leicester, "so we wondered what would happen if gas came in from different directions."
Nixon, King and their colleague Daniel Price in Australia made a computer simulation of two gas discs orbiting a black hole at different angles. After a short time the discs spread and collide, and large amounts of gas fall into the hole. According to their calculations black holes can grow 1,000 times faster when this happens........
"Arsenic is naturally occuring around gold mineralisation and is even used as an indicator in gold exploration, so it can be concentrated in soil..."
Exposure to arsenic in soil and mine waste may have contributed to a slight increase in past cancer risk in socio-economically disadvantaged areas in the Goldfields region of Victoria, according to new research published in the Journal of Exposure Science and Environmental Epidemiology. Researchers from the University of Ballarat have released findings showing that the incidence of some cancers between 1984 and 2003 was slightly higher in areas with higher arsenic levels.
Dr Dora Pearce, now at the Melbourne School of Population Health, University of Melbourne, explored how soil arsenic levels and cancer rates varied across central Victoria.
By using 20 years of data from the Victorian Cancer Registry and a measure of soil arsenic derived from geochemical data provided by the University of Ballarat and GeoScience Victoria, Dr Pearce has concluded that ongoing recorded monitoring of environmental sources of arsenic is needed.
“Arsenic is naturally occurring around gold mineralisation and is even used as an indicator in gold exploration, so it can be concentrated in soil and mine waste dumps that are still scattered across our landscape,” Dr Dora Pearce said.
In the Goldfields region, many residential communities have grown up around historical gold mining areas.
“Our previous research detected small traces of arsenic in toenail clippings from children living in this region, showing that exposure to arsenic in soil could be an ongoing problem and that we should not be too complacent.
“We hope that by raising community awareness of this issue, childhood exposures to arsenic in soil, and future cancer risk, will be reduced in the Goldfields region of Victoria,” Dr Pearce said.
The researchers found twice as many positive and negative ions in heavily wooded areas compared to open grassy areas.
Plants have long been known as the lungs of the Earth, but a new finding has found they may also play a role in electrifying the atmosphere. Scientists have long suspected an association between trees and electricity but researchers from Queensland University of Technology (QUT) think they may have finally discovered the link.
Dr Rohan Jayaratne and Dr Xuan Ling from QUT's International Laboratory for Air Quality and Health (ILAQH), led by Professor Lidia Morawska, ran experiments in six locations around Brisbane, including the Brisbane Forest Park, Daisy Hill and Mt Coot-tha.
They found the positive and negative ion concentrations in the air were twice as high in heavily wooded areas than in open grassy areas, such as parks.
Dr Jayaratne, who is also a member of QUT's Institute of Health and Biomedical Innovation (IHBI), said that natural ions in the air were mainly created by ionisation due to two processes - radiation from the trace gas radon in air and cosmic radiation from space.
Radon is a by-product of the radioactive decay of radium which is present in minute quantities in rocks and is continually exhaled by the ground.
"Because radium is found in rocks and radon is soluble in water, ground water is particularly rich in radon," he said.
"Trees act as radon pumps, bringing the gas to the surface and releasing it to the atmosphere through transpiration - a process where water absorbed by the root system is evaporated into the atmosphere from leaves. This is especially prevalent for trees with deep root systems, such as eucalypts."
The QUT scientists estimated that, in a eucalyptus forest, trees may account for up to 37 per cent of the radon in the air when transpiration rates were highest.
Dr Jayaratne said though there was still a lot more research which needed to be done in relation to the role of ions, the findings, which were published in the journal Environmental Science and Technology, have potentially important implications for the atmosphere, climate and human health.
"Although there is an established link between airborne particles and human health, the role of ions is largely unknown," he said.
"However, we do know that approximately one-half of the particles that we inhale during normal breathing are retained in our respiratory system and it has been shown that charged particles were more likely to be deposited in the lungs than uncharged particles.
"We do not believe that ions are dangerous - the danger comes from the pollutants. If there are no dangerous particles in the air to attach to the ions there is no risk of ill health."
Cancer cells flowing inside a vein with blood cells
A multi-national research team led by scientists at Duke-NUS Graduate Medical School has identified the reason why some patients fail to respond to some of the most successful cancer drugs. Tyrosine kinase inhibitor drugs (TKIs) work effectively in most patients to fight certain blood cell cancers, such as chronic myelogenous leukemia (CML), and non-small-cell lung cancers (NSCLC) with mutations in the EGFR gene.
These precisely targeted drugs shut down molecular pathways that keep these cancers flourishing and include TKIs for treating CML, and the form of NSCLC with EGFR genetic mutations.
Now the team at Duke-NUS Graduate Medical School in Singapore, working with the Genome Institute of Singapore (GIS), Singapore General Hospital and the National Cancer Centre Singapore, has discovered that there is a common variation in the BIM gene in people of East Asian descent that contributes to some patients' failure to benefit from these tyrosine kinase inhibitor drugs.
“Because we could determine in cells how the BIM gene variant caused TKI resistance, we were able to devise a strategy to overcome it,” said S. Tiong Ong, M.B.B. Ch.., senior author of the study and associate professor in the Cancer and Stem Cell Biology Signature Research Programme at Duke-NUS and Division of Medical Oncology, Department of Medicine, at Duke University Medical Center.
“A novel class of drugs called the BH3-mimetics provided the answer,” Ong said. “When the BH3 drugs were added to the TKI therapy in experiments conducted on cancer cells with the BIM gene variant, we were able to overcome the resistance conferred by the gene. Our next step will be to bring this to clinical trials with patients.”
Said Yijun Ruan, Ph.D., a co-senior author of this study and associate director for Genome Technology and Biology at GIS: “We used a genome-wide sequencing approach to specifically look for structural changes in the DNA of patient samples. This helped in the discovery of the East Asian BIM gene variant. What’s more gratifying is that this collaboration validates the use of basic genomic technology to make clinically important discoveries.”
The study was published online in Nature Medicine on March 18.
If the drug combination does override TKI resistance in people, this will be good news for those with the BIM gene variant, which occurs in about 15 percent of the typical East Asian population. By contrast, no people of European or African ancestry were found to have this gene variant.
“While it’s interesting to learn about this ethnic difference for the mutation, the greater significance of the finding is that the same principle may apply for other populations,” said Patrick Casey, Ph.D., senior vice dean for research at Duke-NUS and James B. Duke Professor of Pharmacology and Cancer Biology. “There may well be other, yet to be discovered gene variations that account for drug resistance in different world populations. These findings underscore the importance of learning all we can about cancer pathways, mutations, and treatments that work for different types of individuals. This is how we can personalize cancer treatment and, ultimately, control cancer.”
“We estimate that about 14,000 newly diagnosed East Asian CML and EGFR non-small-cell lung cancer patients per year will carry the gene variant,” Ong said. “Notably, EGFR NSCLC is much more common in East Asia, and accounts for about 50 percent of all non-small-cell lung cancers in East Asia, compared to only 10 percent in the West.”
The researchers found that drug resistance occurred because of impaired production of BH3-containing forms of the BIM protein. They confirmed that restoring BIM gene function with the BH3 drugs worked to overcome TKI resistance in both types of cancer.
“BH3-mimetic drugs are already being studied in clinical trials in combination with chemotherapy, and we are hopeful that BH3 drugs in combination with TKIs can actually overcome this form of TKI resistance in patients with CML and EGFR non-small-cell lung cancer,” Ong said. “We are working closely with GIS and the commercialization arm of the Agency for Science, Technology & Research (A*STAR), to develop a clinical test for the BIM gene variant, so that we can take our discovery quickly to the patient.”.......
As a person with a profound hatred of even the thought of lying, so won't do it on principle, I don't believe that this would be the case with me. However this is about the average member of the general public. Nice picture by the way.
Lying brings more satisfaction
"When people lie, they're so preoccupied with telling the lie and not revealing the truth that they aren't able to monitor cues from the listener..."
Honesty may be the best policy, but new research from the University of Sydney suggests that consumers feel more satisfied if they lie and get what they want than if they tell the truth.
The study, to be published in the Journal of Consumer Research by Dr Christina Anthony and Professor Elizabeth Cowley of the University of Sydney Business School, found that people who lie during a service encounter have more extreme reactions to the outcome than their honest peers.
The research raises interesting questions about the way marketers and businesses respond to dishonest customers and train their staff, particularly given the volume of lies people tell every day - previous research shows that people tell on average one to two lies a day, which equates to about 42,000 lies before the age of 60.
"Lying is hard work. When people lie, they're so preoccupied with telling the lie and not revealing the truth that they aren't able to monitor cues from the listener, which are important for updating expectations about the likely outcome of the conversation. This means that they are more surprised by the outcome and so have a stronger reaction to it," says Dr Anthony.
"So when you lie to get a refund or to file an insurance claim and get away with it, you will have a much more polarised reaction than if you had told the truth. People who lie are more satisfied than truth tellers if they get a favourable outcome and more dissatisfied if they get an unfavourable outcome."
The researchers conducted a series of lab experiments in which participants either told the truth or lied during a conversation with a service provider in order to get a material reward. This included lying to a salesperson about better competitor offers to secure a more favourable deal and lying to obtain a refund that fell outside the terms of the refund policy.
In one experiment, participants were asked to answer some questions about a consumer product and told that some of them would receive the product as a prize if they met some pre-determined criteria. Half of the participants were then informed that they were eligible for the prize, even though their responses did not match the specified eligibility criteria - and they knew it. Participants therefore had a choice: to lie and get the prize, or to correct the error and miss out.
"We found that about 50 percent of participants in this situation chose to lie. They were more thrilled with the outcome when they got the prize and more disappointed when they missed out," says Dr Anthony.
The fact that customers who lie have more extreme reactions to service encounters also has important consequences for businesses and marketers, says Dr Anthony.
"Because a successful lie may boost satisfaction with a transaction, it may be wise in some instances to turn a blind eye if the company doesn't have too much to lose financially."
"If marketers are overly cautious of dishonest consumers, they also run the risk of wrongly accusing and alienating people who are telling the truth."
Ultra-fast camera can create images of hidden objects using scattered laser light.
The ability to see objects hidden behind walls could be invaluable in dangerous or inaccessible locations, such as inside machinery with moving parts, or in highly contaminated areas. Now scientists at the Massachusetts Institute of Technology in Cambridge have found a way to do just that.
They fire a pulse of laser light at a wall on the far side of the hidden scene, and record the time at which the scattered light reaches a camera. Photons bounce off the wall onto the hidden object and back to the wall, scattering each time, before a small fraction eventually reaches the camera, each at a slightly different time. It's this time resolution that provides the key to revealing the hidden geometry. The position of the 50-femtosecond (that’s 50 quadrillionths of a second) laser pulse is also changed 60 times, to gain multiple perspectives on the hidden scene.
"We are all familiar with sound echoes, but we can also exploit echoes of light," says Ramesh Raskar, head of the Camera Culture Research Group at the MIT Media Lab which carried out the study.
A normal camera can only see objects that are right in front of it. Light that reaches the sensor from beyond the direct line of sight is too diffuse to convey useful information about the hidden scene, having been scattered by multiple reflections. The new set-up, described today in Nature Communications1, overcomes this problem by capturing ultra-fast time-of-flight information — that is, how long each photon has taken to reach the camera. This information is then decoded by a reconstruction algorithm concieved by team member Andreas Velten........
To dissect evolution, Joe Thornton resurrects proteins that have been extinct for many millions of years. His findings rebut creationists and challenge polluters.
Halfway through breakfast, Joe Thornton gets a call from his freezer. A local power cut has triggered an alarm on the −80 °C appliance in his lab at the University of Oregon in Eugene, and it has sent out an automatic call. Thornton breaks off our conversation and calls his senior research scientist, Jamie Bridgham, to make sure that the back-up generator has kicked in. If the freezer starts warming up, a lot could be lost — not least a valuable collection of proteins that had been extinct for hundreds of millions of years until Thornton and his team brought them back from the dead.
One deep-frozen vial holds the more-than-600-million-year-old ancestor of the receptors for oestrogen, cortisol and other hormones, which Thornton brought to life1 nine years ago. Other tubes house proteins more than 400 million years old, which Thornton resurrected a few years later to show how an ancient receptor had changed its preferences — and how the march of evolution cannot be reversed2, 3, 4. In another corner of the freezer rest the ancient protein components of a sophisticated cellular machine that acquired a more complex form through random mutations rather than selection for superior function, as the group showed in Nature this January5. The sheer awe of working with long-dead proteins doesn't fade, says Thornton. “It's amazing. The ability to do this type of time travel is fantastic.”
Thornton is a leader in a movement to do for proteins what the scientists in Jurassic Park did for dinosaurs: bring ancient forms back to life, so that they can be studied in the flesh. “Instead of passively observing things as most evolutionary biologists do, you actively go in and test the hypotheses experimentally,” says Antony Dean, a molecular biologist at the University of Minnesota in St Paul who heads another major group in the field. “His is one of the leading labs, no doubt.” And Thornton is tackling some important questions, says Kenneth Miller, a molecular biologist at Brown University in Providence, Rhode Island. “He's helping to put some flesh on the bones of speculation about how complexity arises.”
What isn't so widely known is that evolutionary biology is Thornton's second career: in his first, he was an activist for Greenpeace, campaigning vigorously against the release of toxic chemicals. He wrote a controversial book on organochlorines: industrial chemicals that include dioxins, polychlorinated biphenyls (PCBs) and pesticides such as DDT. That activist legacy bleeds into his work today, for example in his focus on the oestrogen receptor, which is corrupted by many pollutants. The grubby, sea-green tiles under Thornton's lab benches were carefully sourced to be free of polyvinyl chloride (PVC), one of the organochlorines that worries him most. His activist past also helps to explain why he has been fearless — almost enthusiastic — about highlighting the challenge that his work presents to a creationist argument called intelligent design: the claim that complex molecular systems can only have been created by a divine force. Thornton shows how evolution did the job, leaving no need for a designer.
Environment to evolution
Thornton says that his activist days — during which he saw that many risk-assessment models were shot through with assumptions and biases — left him “intensely committed to methodological reductionism and experimentalism”, which he now uses to break evolution down into detailed steps that he can test. “If you're doing science, I think it ought to be as strong and decisive as possible,” he says. “If you're doing politics, go ahead, but don't try to disguise it as science.”........
Findings help to explain how microbes programme a developing immune system
Dig in: eating dirt and playing in the mud are thought to confer protection from allergies and asthma.
Exposure to germs in childhood is thought to help strengthen the immune system and protect children from developing allergies and asthma, but the pathways by which this occurs have been unclear. Now, researchers have identified a mechanism in mice that may explain the role of exposure to microbes in the development of asthma and ulcerative colitis, a common form of inflmatory bowel disease.
In a study published online today in Science1, the researchers show that in mice, exposure to microbes in early life can reduce the body’s inventory of invariant natural killer T (iNKT) cells, which help to fight infection but can also turn on the body, causing a range of disorders such as asthma or inflammatory bowel disease.
The study supports the 'hygiene hypothesis', which contends that such auto-immune diseases are more common in the developed world where the prevalence of antibiotics and antibacterials reduce children’s exposure to microbes.
“We as a species are not exposed to the same germs that we were exposed to in the past,” says study co-author Dennis Kasper, a microbiologist at Harvard Medical School in Boston, Massachusetts.
The researchers induced two groups of mice — germ-free (GF) mice, which are raised in a sterile environment, and specific-pathogen-free mice raised under normal laboratory conditions — to develop forms of asthma or ulcerative colitis. GF mice had more iNKT cells in their lungs and developed more severe disease symptoms, indicating that exposure to microbes was somehow influencing iNKT cell levels and making the GF mice more susceptible to inflammatory diseases.
The study also found that a lack of exposure in early life could not be compensated for by introducing the GF mice to a broader range of microbes in adulthood.
In search of a mechanism to explain the influence of exposure to microbes, the researchers homed in on CXCL16, a signaling protein associated with inflammation and iNKT cells. Expression of CXCL16 was higher in the colon and lung tissue of GF mice than in normal mice, and blocking that expression reduced the numbers of iNKT cells and the amount of inflammation in those tissues.
Germs and genes
An analysis of the gene encoding CXCL16 showed that five regions of the gene were hyper-expressed in germ-free mice owing to DNA methylation — the tacking on of molecules to the DNA strand which can alter the production of particular proteins. “We then fiddled around with different compounds that could control methylation of the DNA,” explains Kasper. “Methylation up-regulated CXCL16, and resulted in higher iNKT cell levels.”
Kasper says that these results suggested a pathway: without exposure to certain microbes, methylation increases CXCL16 expression, which ultimately increases iNKT cell numbers and inflammation.
“There probably are some specific organisms and molecules produced by those organisms that influence this pathway,” says Kasper. “It seems like there’s something that sets the thermostat at a very, very young age, but we don’t know what it is.”........
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Topic: Science and Nature News Redux
