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thinkahol *

Short Sharp Science: Half a heartbeat changes our response to scary images - 0 views

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    In another study, in which volunteers saw the same pictures while having their brain scanned using MRI, she found that people had a stronger response in the hippocampus and amygdala - areas of the brain associated with fear - when they were shown fearful faces at systole than when they saw them at diastole. In other words, half a heartbeat was all it took for a person to experience a significantly different response to the same scary stimulus.
Erich Feldmeier

@PeterSpork #epigenetik #sleep BBC News - How much can an extra hour's sleep change you? - 0 views

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    Dr Simon Archer and his team at Surrey University were particularly interested in looking at the genes that were switched on or off in our volunteers by changes in the amount that we had made them sleep. "We found that overall there were around 500 genes that were affected," Archer explained. "Some which were going up, and some which were going down." What they discovered is that when the volunteers cut back from seven-and-a-half to six-and-a-half hours' sleep a night, genes that are associated with processes like inflammation, immune response and response to stress became more active. The team also saw increases in the activity of genes associated with diabetes and risk of cancer. The reverse happened when the volunteers added an hour of sleep. So the clear message from this experiment was that if you are getting less than seven hours' sleep a night and can alter your sleep habits, even just a little bit, it could make you healthier
Erich Feldmeier

@NerdyChristie "A ship is safe in harbor, but that's not what ships are for." - 0 views

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    ""A ship is safe in harbor, but that's not what ships are for." By Christie Wilcox | February 14, 2013 A year and a half ago, the decision to pack up shop at ScienceBlogs and begin blogging at Scientific American was an easy one. The inimitable Bora Zivkovic had assembled a blogging dream team, a group of people I respected and admired and couldn't wait to call networkmates. Under Bora's nurturing oversight, we all have flourished, and the SciAm blog network has become the most diverse and prolific science blogging network around"
Erich Feldmeier

Robin Mellors-Bourne: #Vitae #STEM Researchers' 'unrealistic' hopes of academic careers... - 0 views

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    "There is a "significant credibility gap" between researchers' expectations and the likelihood of their forging long-term careers in higher education, a survey has found. More than three-quarters of research staff responding to the Careers in Research Online Survey 2013 said they aspired to a career in higher education and around two-thirds said they expected to achieve this. But it was "unrealistic to expect" that this number of research staff, or even half of those in the early stages of their career, would be able to secure a long-term research role in higher education, says the report, based on the survey produced by Vitae, the careers organisation for researchers."
thinkahol *

Most new farmland in tropics comes from slashing forests, research shows - 0 views

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    ScienceDaily (Sep. 4, 2010) - Global agricultural expansion cut a wide swath through tropical forests during the 1980s and 1990s. More than half a million square miles of new farmland -- an area roughly the size of Alaska -- was created in the developing world between 1980 and 2000, of which over 80 percent was carved out of tropical forests, according to Stanford researcher Holly Gibbs.
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

Tally of Antarctic Sealife Sheds Light on Changing Climate - 0 views

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    More than 6,000 different species living on the sea-floor have been identified so far and more than half of these are unique to the icy continent. A combination of long-term monitoring studies, newly gathered information on the marine life distribution and global ocean warming models, enable the scientists to identify Antarctica's marine "biodiversity hotspots". Researcher Griffiths describes how krill populations (the shrimp-like invertebrates eaten by penguins, whales and seals) are reducing as a result of a decrease in sea-ice cover. A much smaller crustacean (copepods) is dominating the area once occupied by them. This shifts the balance of the food web to favour predators, like jellyfish, that are not eaten by penguins and other Southern Ocean higher predators. Sea-ice reduction is also affecting penguins that breed on the ice.
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 *

The Epidemic of Mental Illness: Why? by Marcia Angell | The New York Review of Books - 0 views

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    It seems that Americans are in the midst of a raging epidemic of mental illness, at least as judged by the increase in the numbers treated for it. The tally of those who are so disabled by mental disorders that they qualify for Supplemental Security Income (SSI) or Social Security Disability Insurance (SSDI) increased nearly two and a half times between 1987 and 2007-from one in 184 Americans to one in seventy-six. For children, the rise is even more startling-a thirty-five-fold increase in the same two decades. Mental illness is now the leading cause of disability in children, well ahead of physical disabilities like cerebral palsy or Down syndrome, for which the federal programs were created.
thinkahol *

5 Things That Internet Porn Reveals About Our Brains | Sex & the Brain | DISCOVER Magazine - 1 views

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    With its expansive range and unprecedented potential for anonymity, (the Internet gives voice to our deepest urges and most uninhibited thoughts. Inspired by the wealth of unfettered expression available online, neuroscientists Ogi Ogas and Sai Gaddam, who met as Ph.D. candidates at Boston University, began plumbing a few chosen search engines (including Dogpile and AOL) to create the world's largest experiment in sexuality in 2009. Quietly tapping into a billion Web searches, they explored the private activities of more than 100 million men and women around the world. The result is the first large-scale scientific examination of human sexuality in more than half a century, since biologist Alfred Kinsey famously interviewed more than 18,000 middle-class Caucasians about their sexual behavior and published the Kinsey reports in 1948 and 1953. Building on the work of Kinsey, neuroscientists have long made the case that male and female sexuality exist on different planes. But like Kinsey himself, they have been hampered by the dubious reliability of self-reports of sexual behavior and preferences as well as by small sample sizes. That is where the Internet comes in. By accessing raw data from Web searches and employing the help of Alexa-a company that measures Web traffic and publishes a list of the million most popular sites in the world-Ogas and Gaddam shine a light on hidden desire, a quirky realm of lust, fetish, and kink that, like the far side of the moon, has barely been glimpsed. Here is a sampling of their fascinating results, selected from their book, A Billion Wicked Thoughts.
thinkahol *

How your memories can be twisted under social pressure | KurzweilAI - 1 views

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    Listen up, Facebook and Twitter groupies: how easily can social pressure affect your memory? Very easily, researchers at the Weizmann Institute and University College London have proved, and they think they even know what part of the brain is responsible. The participants conformed to the group on these "planted" responses, giving incorrect answers nearly 70% of the time. Volunteers watched a documentary film in small groups. Three days later, they returned to the lab individually to take a memory test, answering questions about the film. They were also asked how confident they were in their answers. They were later invited back to the lab to retake the test. This time, the subjects were also given supposed answers of the others in their film-viewing group (along with social-media-style photos) while being scanned in a functional MRI (fMRI) that revealed their brain activity. Is most of what you know false? Planted among these were false answers to questions the volunteers had previously answered correctly and confidently. The participants conformed to the group on these "planted" responses, giving incorrect answers nearly 70% of the time. To determine if their memory of the film had actually undergone a change, the researchers invited the subjects back to the lab later to take the memory test once again, telling them that the answers they had previously been fed were not those of their fellow film watchers, but random computer generations. Some of the responses reverted back to the original, correct ones, but get this: despite finding out the scientists messed with their minds, close to half of their responses remained erroneous, implying that the subjects were relying on false memories implanted in the earlier session. An analysis of the fMRI data showed a strong co-activation and connectivity between two brain areas: the hippocampus and the amygdala. Social reinforcement could act on the amygdala to persuade our brains to replace a strong memory wi
Barry mahfood

Raised Imperishable? - 0 views

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    A bit of backstory is required here. I spent half of my life as a Christian minister. I am no longer a Christian, and obviously not a minister. Today I am an atheistic blogger, although the focus of my blogs is unrelated to atheism. I tell you this not to offend those of you who believe in God, not to curry favor with those of you who do not. I only mention it because I will quote some scripture in this post, but the post is about religion. It is about the singularity, transhumanism, and radical life-extension. So please bear with me.
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.
popisc

How Does Solar Work? - 1 views

The amount of sunlight that reaches Earth's surface in just more than an hour and a half might provide enough energy for the whole planet for an entire year. These include photovoltaic (PV) panels ...

solar

started by popisc on 06 Feb 23 no follow-up yet
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