QuoteReplyTopic: Science and Nature News Redux Posted: 22-Mar-2012 at 17:06
Venice Hasn't Stopped Sinking After All
Venice.
The water flowing through Venice's famous canals laps at buildings a little higher every year -- and not only because of a rising sea level. Although previous studies had found that Venice has stabilized, new measurements indicate that the historic city continues to slowly sink, and even to tilt slightly to the east.
"Venice appears to be continuing to subside, at a rate of about 2 millimeters (.07 inches) a year," said Yehuda Bock, a research geodesist with Scripps Institution of Oceanography at UC San Diego, and the lead author of the new research paper on the city's downward drift. "It's a small effect, but it's important," he added. Given that sea level is rising in the Venetian lagoon, also at 2 millimeters per year, the slight subsidence doubles the rate at which the heights of surrounding waters are increasing relative to the elevation of the city, he noted. In the next 20 years, if Venice and its immediate surroundings subsided steadily at the current rate, researchers would expect the land to sink up to 80 millimeters (3.2 inches) in that period of time, relative to the sea.
Bock worked with colleagues from the University of Miami in Florida and Italy's Tele-Rilevamento Europa, a company that measures ground deformation, to analyze data collected by GPS and space-borne radar (InSAR) instruments regarding Venice and its lagoon. The GPS measurements provide absolute elevations, while the InSAR data are used to calculate elevations relative to other points. By combining the two datasets from the decade between 2000 and 2010, Bock and his colleagues found that the city of Venice was subsiding on average of 1 to 2 millimeters a year (0.04 to 0.08 inches per year). The patches of land in Venice's lagoon (117 islands in all) are also sinking, they found, with northern sections of the lagoon dropping at a rate of 2 to 3 millimeters (0.08 to 0.12 inches) per year, and the southern lagoon subsiding at 3 to 4 millimeters (0.12 to 0.16 inches) per year.
The findings will be published March 28 in Geochemistry, Geophysics, Geosystems, a journal of the American Geophysical Union.
"Our combined GPS and InSAR analysis clearly captured the movements over the last decade that neither GPS nor InSAR could sense alone" said Shimon Wdowinski, associate research professor of Marine Geology and Geophysics at the University of Miami.
In the new study, using the GPS instruments, Bock and his colleagues were able to take absolute readings of the city and its surrounding lagoons. And not only did they find the sinking, but they found that the area was tilting a bit, about a millimeter or two eastward per year. That means the western part -- where the city of Venice is -- is higher than the eastern sections. Prior satellite analyses didn't pick up on the tilt, Bock said, possibly because the scientists had been taking measurements using InSAR, which only provided the change elevation relative to other sites........
The study suggested a gene variation could contribute to the weight of a newborn child
Scientists say a gene variation could contribute up to 155g (5.5oz) to a child's birthweight.
The gene studied is believed to act as a growth suppressor, reducing birthweight.
But the UK-based researchers found a particular variant passed down from the mother can add 93g (3.3oz) to the birthweight, or 155g if passed down from the maternal grandmother.
Details are published in the American Journal of Human Genetics.
Professor Gudrun Moore of University College London and colleagues looked at a gene called PHLDA2 in nearly 9,500 DNA samples taken from mothers and their babies, collected in three separate studies.
They found a gene variant called RS1 appeared to change the way in which the gene functioned, leading to higher birthweights.
"The gene is already known to have a profound effect on birthweight by acting as a growth suppressor," Prof Moore told BBC News.
"We have found a genetic variant of PHLDA2 that when inherited from the mother, causes the baby to be 93g bigger on average, or even 155g bigger on average, if inherited successively from the mother's mother."
The RS1 variation was found in around 13% of the individuals studied, with 87% possessing the RS2 variation.
"We suggest that the more common RS2 gene variation, which is only found in humans, has evolved to produce a smaller baby as a protective effect to enhance the mother's survival during childbirth," said Prof Moore.
"Dad's lack of involvement in evolutionary terms may stem from his own survival not being at stake and he can continue to reproduce with other females."
Gene 'silenced'
The PHLDA2 gene is unusual in that only the copy inherited from the mother is active, while the copy inherited from the father is "silenced". This silencing of the paternal gene results from molecular processes around the DNA known as epigenetics.
Scientists do not know why, but have speculated that it is to ensure birthweight is reduced to ensure the mother survives childbirth.
Dr Caroline Relton of Newcastle University said: "Although this study looks only at birthweight as an outcome, it is possible that this genetic variant may have longer-term health consequences.
"Indeed the long-term health consequences associated with extremes of birthweight might be due in part to this and other contributory genetic factors."
Written By Jennifer Welsh-Published March 21, 2012-LiveScience
Captive chimpanzees learn from their mothers to call out to humans, new research suggests. Those chimps raised by their moms were also most likely to use similar calls, from lip-smacking to blowing kisses.
This teaching from mother to child is an example of "social learning," which played an important role in the development of human culture and language.
While social learning of tool use has been seen in chimps before, "it has never really been shown for communication before," study researcher Jared Taglialatela, an assistant professor at Kennesaw State University in Georgia, told LiveScience. Before this study, he said, "social learning of communication signals was seen as unique to human language."
Written By Brian Jacobsmeyer-Published March 22, 2012-Inside Science News Service
Jupiter might be having a change of heart. Literally.
New simulations suggest that Jupiter's rocky core has been liquefying, melting, and mixing with the rest of the planet's innards. With this new data, astronomers hope to better explain a recent puzzling discovery of a strange planet outside of our solar system.
"It's a really important piece of the puzzle of trying to figure out what's going on inside giant planets," said Jonathan Fortney, a planetary scientist at the University of California Santa Cruz who was not affiliated with the research.
Conventional planetary formation theory has modeled Jupiter as a set of neat layers with a gassy outer envelope surrounding a rocky core consisting of heavier elements. But increasing evidence has indicated that the insides of gas giants like Jupiter are a messy mixture of elements without strictly defined borders.
World’s Most Powerful Laser Fires Most Powerful Laser Blast in History
Published March 21, 2012-FoxNews.com
The largest laser in the world was turned on for a fraction of a second last week -- and it unleashed the most powerful laser blast in history.
The National Ignition Facility (NIF) -- a laser test facility at Lawrence Livermore National Laboratory in Livermore, Calif. -- turned on its 192 laser beams for a brief instant on March 15, unleashing a record-setting 1.875-megajoule blast into a target chamber. The lasers were combined, gathered and focused through a series of lens into a 2.03-megajoule shot, said Ed Moses, NIF director -- a record for the facility. That pulse of energy lasted for just 23 billionths of a second, yet it generated 411 trillion watts of power, NIF said -- 1,000 times more than the entire United States consumes at any given instant.
"...ScienceDaily (Mar. 14, 2012) — The origin of
the exquisitely complex vertebrate brain is somewhat mysterious. "In
terms of evolution, it basically pops up out of nowhere. You don't see
anything anatomically like it in other animals," says Ariel Pani, an
investigator at the Marine Biological Laboratory (MBL) in Woods Hole and
a graduate student at the University of Chicago. ScienceDaily (Mar. 14, 2012) — The origin of
the exquisitely complex vertebrate brain is somewhat mysterious. "In
terms of evolution, it basically pops up out of nowhere. You don't see
anything anatomically like it in other animals," says Ariel Pani, an
investigator at the Marine Biological Laboratory (MBL) in Woods Hole and
a graduate student at the University of Chicago....
.."What this means is the last (common) ancestor of the hemichordates and
the vertebrates, even though it presumably did not have a
vertebrate-like nervous system, had some very complex and
vertebrate-like mechanisms for establishing its body plan," Pani says.
"And one of the broad implications is that weird, squishy marine animals
can be very informative in terms of understanding the evolution of
vertebrate development and genetics in a way that you wouldn't expect."... http://www.sciencedaily.com/releases/2012/03/120314142843.htm.
Is a project to map the brain’s full communications network worth the money?
The nerve fibres of the author's brain were traced by diffusion spectrum imaging, and coloured to represent their direction.
A building that once housed a Second World War torpedo factory seems an unlikely location for a project aiming to map the human brain. But the Martinos Center for Biomedical Imaging — an outpost of the Massachusetts General Hospital in an industrialized stretch of Boston's riverfront — is home to an impressive collection of magnetic resonance imaging machines. In January, I slid into the newest of these, head first. The operator ran a few test sequences to see whether I experienced any side effects from the unusually rapid changes in this machine's magnetic field. And, when I didn't — no involuntary muscle twitches or illusory flashes of light in my peripheral vision — we began. The machine hummed, then started to vibrate. For 90 minutes, I held still as it scanned my brain.
That scan would be one of the first carried out by the Human Connectome Project (HCP), a five-year, US$40-million initiative funded by the National Institutes of Health (NIH) in Bethesda, Maryland, to map the brain's long-distance communications network. The network, dubbed the 'connectome', is a web of nerve-fibre bundles that criss-cross the brain in their thousands and form the bulk of the brain's white matter. It relays signals between specialized regions devoted to functions such as sight, hearing, motion and memory, and ties them together into a system that perceives, decides and acts as a unified whole.
The connectome is bewilderingly complex and poorly understood. The HCP proposes to resolve this by using new-generation magnetic resonance imaging (MRI) machines, like that used to scan my brain, to trace the connectomes of more than 1,000 individuals. The hope is that this survey will establish a baseline for what is normal, shed light on what the variations might mean for qualities such as intelligence or sociability, and possibly reveal what happens if the network goes awry. “We increasingly believe that brain disorders — from schizophrenia to depression to post-traumatic stress disorder — are disorders of connectivity,” says Thomas Insel, director of the National Institute of Mental Health (NIMH) in Bethesda and a strong supporter of the HCP. “So it is of vital importance that we have ways of detecting and quantifying these connections.”
Yet many wonder whether the NIH is making a mistake. Researchers have yet to prove that MRI techniques can produce a reliable picture of normal connectivity, never mind the types of abnormal connection likely to be found in brain disorders, and some researchers argue that the techniques have not been adequately validated. “I would do the basic neuroscience before I started running lots of people through MRI scanners,” says David Kleinfeld, a physics and neurobiology researcher at the University of California, San Diego.
The grand challenge
Proponents counter that the HCP is a calculated risk. “No one thinks this is going to produce a wiring diagram like you might have for the electricity in your house,” says Insel. But so little is known about the connectome, he says, that even crude maps would represent a major scientific advance.
The decision to take that risk was made by the NIH's Blueprint for Neuroscience Research, set up in 2004 as a collaboration among the 15 NIH institutes, centres and offices with an interest in nervous-system research. In 2009, after five years of funding smaller projects, the group asked officials from across the NIH to submit ideas for 'grand challenges' in neuroscience: large-scale programmes that, Insel says, “would be both extremely high-impact, and virtually impossible with traditional grant mechanisms”.
The Blueprint group received a dozen submissions, including one from Michael Huerta, then a programme officer at the NIMH and a member of a Blueprint subcommittee. Huerta, now at the NIH's National Library of Medicine, began his research career studying the organization of mammalian brains using old-school anatomical and neural-tracing techniques, which typically require the injection of a tracer compound that migrates along nerve fibres and reveals their routes. So he was all too familiar with the barriers to such studies in humans. For ethical reasons, tracers can only be used post-mortem — when they don't migrate far enough to trace a fibre's full length. “The studies just never panned out,” says Huerta..........
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.”........
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.”........
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........
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."
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.”.......
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."
"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.
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........
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.........
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.........
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.
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.".......
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Topic: Science and Nature News Redux
