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Charles Daney

Liposuction leftovers provide "liquid gold" stem cells - Just A Theory - 0 views

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    What happens to fat left over from a liposuction procedure? Brad Pitt might choose to turn it in to soap, but scientists at Stanford University have figured out a surprising alternative: stem cells.
Walid Damouny

Explained: The Shannon limit - 0 views

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    "It's the early 1980s, and you're an equipment manufacturer for the fledgling personal-computer market. For years, modems that send data over the telephone lines have been stuck at a maximum rate of 9.6 kilobits per second: if you try to increase the rate, an intolerable number of errors creeps into the data."
Skeptical Debunker

Belief In Climate Change Hinges On Worldview : NPR - 0 views

  • "People tend to conform their factual beliefs to ones that are consistent with their cultural outlook, their world view," Braman says. The Cultural Cognition Project has conducted several experiments to back that up. Participants in these experiments are asked to describe their cultural beliefs. Some embrace new technology, authority and free enterprise. They are labeled the "individualistic" group. Others are suspicious of authority or of commerce and industry. Braman calls them "communitarians." In one experiment, Braman queried these subjects about something unfamiliar to them: nanotechnology — new research into tiny, molecule-sized objects that could lead to novel products. "These two groups start to polarize as soon as you start to describe some of the potential benefits and harms," Braman says. The individualists tended to like nanotechnology. The communitarians generally viewed it as dangerous. Both groups made their decisions based on the same information. "It doesn't matter whether you show them negative or positive information, they reject the information that is contrary to what they would like to believe, and they glom onto the positive information," Braman says.
  • "Basically the reason that people react in a close-minded way to information is that the implications of it threaten their values," says Dan Kahan, a law professor at Yale University and a member of The Cultural Cognition Project. Kahan says people test new information against their preexisting view of how the world should work. "If the implication, the outcome, can affirm your values, you think about it in a much more open-minded way," he says. And if the information doesn't, you tend to reject it. In another experiment, people read a United Nations study about the dangers of global warming. Then the researchers told the participants that the solution to global warming is to regulate industrial pollution. Many in the individualistic group then rejected the climate science. But when more nuclear power was offered as the solution, says Braman, "they said, you know, it turns out global warming is a serious problem."And for the communitarians, climate danger seemed less serious if the only solution was more nuclear power.
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  • Then there's the "messenger" effect. In an experiment dealing with the dangers versus benefits of a vaccine, the scientific information came from several people. They ranged from a rumpled and bearded expert to a crisply business-like one. The participants tended to believe the message that came from the person they considered to be more like them. In relation to the climate change debate, this suggests that some people may not listen to those whom they view as hard-core environmentalists. "If you have people who are skeptical of the data on climate change," Braman says, "you can bet that Al Gore is not going to convince them at this point." So, should climate scientists hire, say, Newt Gingrich as their spokesman? Kahan says no. "The goal can't be to create a kind of psychological house of mirrors so that people end up seeing exactly what you want," he argues. "The goal has to be to create an environment that allows them to be open-minded."And Kahan says you can't do that just by publishing more scientific data.
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    "It's a hoax," said coal company CEO Don Blankenship, "because clearly anyone that says that they know what the temperature of the Earth is going to be in 2020 or 2030 needs to be put in an asylum because they don't." On the other side of the debate was environmentalist Robert Kennedy, Jr. "Ninety-eight percent of the research climatologists in the world say that global warming is real, that its impacts are going to be catastrophic," he argued. "There are 2 percent who disagree with that. I have a choice of believing the 98 percent or the 2 percent." To social scientist and lawyer Don Braman, it's not surprising that two people can disagree so strongly over science. Braman is on the faculty at George Washington University and part of The Cultural Cognition Project, a group of scholars who study how cultural values shape public perceptions and policy
Skeptical Debunker

It's official: An asteroid wiped out the dinosaurs - Yahoo! News - 0 views

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    A giant asteroid smashing into Earth is the only plausible explanation for the extinction of the dinosaurs, a global scientific team said on Thursday, hoping to settle a row that has divided experts for decades. A panel of 41 scientists from across the world reviewed 20 years' worth of research to try to confirm the cause of the so-called Cretaceous-Tertiary (KT) extinction, which created a "hellish environment" around 65 million years ago and wiped out more than half of all species on the planet. Scientific opinion was split over whether the extinction was caused by an asteroid or by volcanic activity in the Deccan Traps in what is now India, where there were a series of super volcanic eruptions that lasted around 1.5 million years. The new study, conducted by scientists from Europe, the United States, Mexico, Canada and Japan and published in the journal Science, found that a 15-kilometre (9 miles) wide asteroid slamming into Earth at Chicxulub in what is now Mexico was the culprit. "We now have great confidence that an asteroid was the cause of the KT extinction. This triggered large-scale fires, earthquakes measuring more than 10 on the Richter scale, and continental landslides, which created tsunamis," said Joanna Morgan of Imperial College London, a co-author of the review.
Skeptical Debunker

Does promiscuity prevent extinction? - 0 views

  • Known as 'polyandry' among scientists, the phenomenon of females having multiple mates is shared across most animal species, from insects to mammals. This study suggests that polyandry reduces the risk of populations becoming extinct because of all-female broods being born. This can sometimes occur as a result of a sex-ratio distortion (SR) chromosome, which results in all of the Y chromosome 'male' sperm being killed before fertilisation. The all-female offspring will carry the SR chromosome, which will be passed on to their sons in turn resulting in more all-female broods. Eventually there will be no males and the population will die out. For this study, the scientists worked with the fruitfly Drosophila pseudoobscura. They gave some populations the opportunity to mate naturally, meaning that the females had multiple partners. The others were restricted to having one mate each. They bred several generations of these populations, so they could see how each fared over time. Over fifteen generations, five of the twelve populations that had been monogamous became extinct as a result of males dying out. The SR chromosome was far less prevalent in the populations in which females had the opportunity to have multiple mates and none of these populations became extinct. The study shows how having multiple mates can suppress the spread of the SR chromosome, making all-female broods a rarity. This is because males that carry the SR chromosome produce only half as many sperm as normal males. When a female mates with multiple males, their sperm will compete to fertilise her eggs. The few sperm produced by males carrying the SR chromosome are out-competed by the sperm from normal males, and the SR chromosome cannot spread.
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    Promiscuous females may be the key to a species' survival, according to new research by the Universities of Exeter and Liverpool. Published today (25 February) in Current Biology, the study could solve the mystery of why females of most species have multiple mates, despite this being more risky for the individual.
Skeptical Debunker

New Rocket Engine Could Reach Mars in 40 Days - Yahoo! News - 0 views

  • A mission trajectory study estimated that a VASIMR-powered spacecraft could reach the red planet within 40 days if it had a 200 megawatt power source. That's 1,000 times more power than what the current VASIMR prototype will use, although Ad Astra says that VASIMR can scale up to higher power sources. The real problem rests with current limitations in space power sources. Glover estimates that the Mars mission scenario would need a power source that can produce one kilowatt (kW) of power per kilogram (kg) of mass, or else the spacecraft could never reach the speeds required for a quick trip. Existing power sources fall woefully short of that ideal. Solar panels have a mass to power ratio of 20 kg/kW. The Pentagon's DARPA science lab hopes to develop solar panels that can achieve 7 kg/KW, and stretched lens arrays might reach 3 kg/KW, Glover said. That's good enough for VASIMR to transport cargo around low-Earth orbit and to the moon, but not to fly humans to Mars. Ad Astra sees nuclear power as the likeliest power source for a VASIMR-powered Mars mission, but the nuclear reactor that could do the job remains just a concept on paper. The U.S. only ever launched one nuclear reactor into space back in 1965, and it achieved just 50 kg/kW.
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    Future Mars outposts or colonies may seem more distant than ever with NASA's exploration plans in flux, but the rocket technology that could someday propel a human mission to the red planet in as little as 40 days may already exist. A company founded by former NASA astronaut Franklin Chang-Diaz has been developing a new rocket engine that draws upon electric power and magnetic fields to channel superheated plasma out the back. That stream of plasma generates steady, efficient thrust that uses low amounts of propellant and builds up speed over time. "People have known for a long time, even back in the '50s, that electric propulsion would be needed for serious exploration of Mars," said Tim Glover, director of development at the Ad Astra Rocket Company.
Walid Damouny

1 gene lost = 1 limb regained? Scientists demonstrate mammalian regeneration through si... - 1 views

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    "A quest that began over a decade ago with a chance observation has reached a milestone: the identification of a gene that may regulate regeneration in mammals. The absence of this single gene, called p21, confers a healing potential in mice long thought to have been lost through evolution and reserved for creatures like flatworms, sponges, and some species of salamander. In a report published today in the Proceedings of the National Academy of Sciences, researchers from The Wistar Institute demonstrate that mice that lack the p21 gene gain the ability to regenerate lost or damaged tissue."
thinkahol *

Origin of life on Earth: 'Natural' asymmetry of biological molecules may have come from... - 0 views

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    ScienceDaily (Jan. 7, 2011) - Certain molecules do exist in two forms which are symmetrical mirror images of each other: they are known as chiral molecules. On Earth, the chiral molecules of life, especially amino acids and sugars, exist in only one form, either left-handed or right-handed. Why is it that life has initially chosen one form over the other?
Charles Daney

New Subatomic Particle Could Help Explain the Mystery of Dark Matter: Scientific American - 0 views

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    New experiments have revealed tantalizing evidence that sterile neutrinos are not only real but common. Some of them could even be the stuff of the mysterious dark matter astronomers have puzzled over for decades.
Charles Daney

Is it now or never for dark matter WIMPs? - 0 views

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    For several decades, astronomers and cosmologists have been piling up data that indicates most of the matter in the Universe is dark, interacting only via gravity. As modified theories of gravity failed to account for observation, candidates for dark mater were winnowed down until one remained in favor: the weakly interactive massive particle, or WIMP. Over the past several years, potential signals of WIMPs have appeared in space and on Earth; that, combined with the startup of the LHC, has given the research community the sense that it's close to pinning down the identity of the WIMPs. But a review in this week's Nature considers what might happen if we fail.
thinkahol *

Robots learn to share: Why we go out of our way to help one another - 1 views

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    ScienceDaily (May 4, 2011) - Using simple robots to simulate genetic evolution over hundreds of generations, Swiss scientists provide quantitative proof of kin selection and shed light on one of the most enduring puzzles in biology: Why do most social animals, including humans, go out of their way to help each other? In the online, open access journal PLoS Biology, EPFL robotics professor Dario Floreano teams up with University of Lausanne biologist Laurent Keller to weigh in on the oft-debated question of the evolution of altruism genes.
thinkahol *

The brain's connectome -- from branch to branch - 1 views

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    ScienceDaily (July 28, 2011) - The human brain is the most complex of all organs, containing billions of neurons with their corresponding projections, all woven together in a highly complex, three-dimensional web. To date, mapping this vast network posed a practically insurmountable challenge to scientists. Now, however, a research team from the Heidelberg-based Max Planck Institute for Medical Research has developed a method for tackling the mammoth task. Using two new computer programs, KNOSSOS and RESCOP, a group of over 70 students mapped a network of more than 100 neurons -- and they did so faster and more accurately than with previous methods.
thinkahol *

Dr. Daniel G. Nocera - YouTube - 0 views

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    The supply of secure, clean, sustainable energy is arguably the most important scientific and technical challenge facing humanity in the 21st century. Rising living standards of a growing world population will cause global energy consumption to double by mid-century and triple by the end of the century. Even in light of unprecedented conservation, the additional energy needed is simply not attainable from long discussed sources these include nuclear, biomass, wind, geothermal and hydroelectric. The global appetite for energy is simply too much. Petroleum-based fuel sources (i.e., coal, oil and gas) could be increased. However, deleterious consequences resulting from external drivers of economy, the environment, and global security dictate that this energy need be met by renewable and sustainable sources. The dramatic increase in global energy need is driven by 3 billion low-energy users in the non-legacy world and by 3 billion people yet to inhabit the planet over the next half century. The capture and storage of solar energy at the individual level personalized solar energy drives inextricably towards the heart of this energy challenge by addressing the triumvirate of secure, carbon neutral and plentiful energy. This talk will place the scale of the global energy issue in perspective and then discuss how personalized energy (especially for the non-legacy world) can provide a path to a solution to the global energy challenge. Daniel G. Nocera is the Henry Dreyfus Professor of Energy at the Massachusetts Institute of Technology, Director of the Solar Revolutions Project and Director of the Eni Solar Frontiers Center at MIT. His group pioneered studies of the basic mechanisms of energy conversion in biology and chemistry. He has recently accomplished a solar fuels process that captures many of the elements of photosynthesis outside of the leaf. This discovery sets the stage for a storage mechanism for the large scale, distributed, deployment of solar energy. He has b
thinkahol *

Schoolchildren can learn complex subjects on their own | KurzweilAI - 0 views

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    Educational researchers at the Technical University of Munich (TUM) have found that schoolchildren can independently develop strategies for solving complex mathematical tasks, with weaker students proving just as capable as their stronger classmates. Researchers in mathematics education worked with approximately 1600 8th grade high-school students in various German states. Following an introduction to the general topic by their teachers, the school children were given a workbook of geometric tasks that they had to solve on paper and using a computer over four school periods. Calculating the surface area of Gran Canaria was one of the real-world, free-form assignments the students had to tackle. The workbook material included explanations and examples of various problem-solving approaches. The teachers took a back seat during the session but were on hand to answer questions from the children, who worked in pairs. After testing the students' skills before and after the session, the researchers recorded a significant improvement in their capabilities. The students learned to apply mathematics more effectively, the researchers said. The students were also able to call on these skills in a further test three months later. "We expected students who were weaker at math to benefit more from a greater degree of guidance through the module," said professor Kristina Reiss.  "But we didn't see a significant difference between these and stronger students." The researchers also found that there were also no differences between boys and girls. "We now know that students - also those who are weaker in math - have the skills to master even very complex subject matters at their own pace," said Reiss. Topics: Cognitive Science/Neuroscience
Charles Daney

Out There: Water, Water Everywhere -- Space.com - 0 views

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    It's now official that water has been found on the moon, and scientists have long seen it on Mars as well. In fact, water is all over the solar system and the rest of the galaxy - and since water is key to life as we know it, these discoveries raise the hope that we are not in fact alone.
Charles Daney

Phenomenology, Fundamental Physics and Inconsistent Truths : Dynamics of Cats - 0 views

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    The paper, Gentile et al, Nature, 461, 627, 2009, discusses the apparent constant surface mass density of disk galaxies in the centers, over several orders of magnitude in mass and luminosity of galaxies, and that the density, when fit with a cold dark matter inspired density profile for the galaxy halos, leads one to conclude the break radius is such that the inferred cold dark matter density decreases at a radius corresponding to an apparently near constant acceleration.
Walid Damouny

Steadier Traffic Flow Improves Health of Local Infants, Researchers Say - 0 views

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    "The creation of E-ZPass lanes over the past 15 years has significantly improved the health of newborn babies living near highways in the Northeast, according to a Columbia study. The researchers found that reductions in traffic congestion generated by E-ZPass lanes reduced premature birthrates by 10.8 percent and low birth weight by 11.8 percent among infants born within 2 kilometers of toll plazas. The net effect has led to hundreds of millions of dollars in saved medical costs."
Janos Haits

Scientific Network | ResearchGate - 0 views

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    ResearchGate is the professional network for scientists Over 900,000 scientists from 192 countries have already joined.
Erich Feldmeier

Vlastimil Hart: Frontiers in Zoology | Abstract | Dogs are sensitive to small variation... - 0 views

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    "We measured the direction of the body axis in 70 dogs of 37 breeds during defecation (1,893 observations) and urination (5,582 observations) over a two-year period. After complete sampling, we sorted the data according to the geomagnetic conditions prevailing during the respective sampling periods. Relative declination and intensity changes of the MF during the respective dog walks were calculated from daily magnetograms. Directional preferences of dogs under different MF conditions were analyzed and tested by means of circular statistics. Results Dogs preferred to excrete with the body being aligned along the North-south axis under calm MF conditions. This directional behavior was abolished under Unstable MF. The best predictor of the behavioral switch was the rate of change in declination, i.e., polar orientation of the MF. "
Janos Haits

Cetis - expert advice on educational technology and standards - 0 views

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    "Cetis is the Centre for Educational Technology, Interoperability and Standards. Our staff are globally recognised as leading experts on education technology innovation, interoperability and technology standards. For over a decade Cetis has provided strategic, technical and pedagogical advice on educational technology and standards to funding bodies, standards agencies, government, institutions and commercial partners."
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