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Charles Daney

The cosmic comic: Riding early waves - 0 views

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    Two fictitious high-spirited scientists of the institute, passionate surfers, take off to visit the early Universe. Not to do serious research there but to experience the ultimate ride on the plasma waves of the big bang. However, they quickly realize that they would be stuck without their knowledge of the physics of the early Universe.
thinkahol *

Why your brain flips over visual illusions - life - 03 September 2010 - New Scientist - 0 views

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    What happens in your brain when you view illusions in which two separate images can be seen?
thinkahol *

The Biology of Consciousness | WBUR and NPR - On Point with Tom Ashbrook - 0 views

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    "Renegade husband and wife philosophers Pat and Paul Churchland met forty years ago in a college Plato class. Their instincts as philosophers - then and now - run outside the philosophy mainstream. Where most philosophers looked to reason and logic to apprehend the human mind, the Churchlands looked - and look - to science. There is no independent "mind", these two practically say, just the human brain, three pounds of tissue and water, firing away behind all our emotions, beliefs, actions. Consciousness itself, they say, is straight biology, a machine. Once, that sounded esoteric. Now, it's on the frontline of debate over law, soul and life."
Charles Daney

After Years of Search, Breakthrough Discoveries of Alzheimer's Genes - TIME - 0 views

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    Fifteen years since the last discovery of its kind, scientists have finally identified a new set of genes that may contribute to Alzheimer's disease. The three new genes, known as clusterin, complement receptor 1 (CR1) and PICALM, were uncovered by two separate research groups.
Charles Daney

A skull that rewrites the history of man - Science, News - The Independent - 0 views

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    The conventional view of human evolution and how early man colonised the world has been thrown into doubt by a series of stunning palaeontological discoveries suggesting that Africa was not the sole cradle of humankind. Scientists have found a handful of ancient human skulls at an archaeological site two hours from the Georgian capital, Tbilisi, that suggest a Eurasian chapter in the long evolutionary story of man.
Skeptical Debunker

What causes autism? Exploring the environmental contribution : Current Opinion in Pedia... - 0 views

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    Purpose of review: Autism is a biologically based disorder of brain development. Genetic factors - mutations, deletions, and copy number variants - are clearly implicated in causation of autism. However, they account for only a small fraction of cases, and do not easily explain key clinical and epidemiological features. This suggests that early environmental exposures also contribute. This review explores this hypothesis. Recent findings: Indirect evidence for an environmental contribution to autism comes from studies demonstrating the sensitivity of the developing brain to external exposures such as lead, ethyl alcohol and methyl mercury. But the most powerful proof-of-concept evidence derives from studies specifically linking autism to exposures in early pregnancy - thalidomide, misoprostol, and valproic acid; maternal rubella infection; and the organophosphate insecticide, chlorpyrifos. There is no credible evidence that vaccines cause autism. Summary: Expanded research is needed into environmental causation of autism. Children today are surrounded by thousands of synthetic chemicals. Two hundred of them are neurotoxic in adult humans, and 1000 more in laboratory models. Yet fewer than 20% of high-volume chemicals have been tested for neurodevelopmental toxicity. I propose a targeted discovery strategy focused on suspect chemicals, which combines expanded toxicological screening, neurobiological research and prospective epidemiological studies.
Skeptical Debunker

Symbiotic Stars - 0 views

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    Many, perhaps even most stars, are members of binaries -- two stars that orbit each other. Symbiotic stars are a small subset of binaries with an attitude: they display characteristic, dramatic, episodic changes in the spectra of their light because (it is thought) one star of pair is a very hot, small star while the other is a cool giant.
Skeptical Debunker

Exotic Antimatter Created on Earth - Yahoo! News - 0 views

  • Among the many particles that resulted from this crash were bizarre objects called anti-hypertritons. Not only are these things antimatter, but they're also what's called strange matter. Where normal atomic nuclei are made of protons and neutrons (which are made of "up" quarks and "down" quarks), strange nuclei also have so-called Lambda particles that contain another flavor of quark called "strange" as well. These Lambda particles orbit around the protons and neutrons. If all that is a little much to straighten out, just think of anti-hypertritons as several kinds of weird. Though they normally don't exist on Earth, these particles may be hiding in the universe in very hot, dense places like the centers of some stars, and most likely were around when the universe was extremely young and energetic, and all the matter was packed into a very small, sweltering space. "This is the first time they've ever been created in a laboratory or a situation where they can be studied," said researcher Carl Gagliardi of Texas A&M University. "We don't have anti-nuclei sitting around on a shelf that we can use to put anti-strangeness into. Only a few anti-nuclei have been observed so far." These particles weren't around for too long, though – in fact, they didn't last long enough to collide with normal matter and annihilate. Instead they just decayed after a fraction of a billionth of a second. "That sounds like a really short time, but in fact on the nuclear clock it's actually a long time," Gagliardi told SPACE.com. "In that fraction of a billionth of a second that Lambda particle has already gone around the nucleus as many times as the Earth has gone around the sun since the solar system was created."
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    Scientists have created a never-before seen type of exotic matter that is thought to have been present at the earliest stages of the universe, right after the Big Bang. The new matter is a particularly weird form of antimatter, which is like a mirror-image of regular matter. Every normal particle is thought to have an antimatter partner, and if the two come into contact, they annihilate. The recent feat of matter-tinkering was accomplished by smashing charged gold atoms at each other at super-high speeds in a particle accelerator called the Relativistic Heavy Ion Collider at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory in Upton, N.Y.
thinkahol *

98.6 degrees Fahrenheit ideal temperature for keeping fungi away and food at bay - 0 views

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    ScienceDaily (Dec. 22, 2010) - Two researchers at Albert Einstein College of Medicine of Yeshiva University have found that our 98.6° F (37° C) body temperature strikes a perfect balance: warm enough to ward off fungal infection but not so hot that we need to eat nonstop to maintain our metabolism.
thinkahol *

YouTube - Sam Harris SALT - 2 views

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    December 9th, 02005 - Sam Harris"The View From The End Of The World"This is an audio only presentation. This talk took place in the Conference Center Golden Gate Room, San Francisco. Quote: With gentle demeanor and tight argument, Sam Harris carried an overflow audience into the core of one of the crucial issues of our time: What makes some religions lethal? How do they employ aggressive irrationality to justify threatening and controlling non-believers as well as believers? What should be our response? Harris began with Christianity. In the US, Christians use irrational arguments about a soul in the 150 cells of a 3-day old human embryo to block stem cell research that might alleviate the suffering of millions. In Africa, Catholic doctrine uses tortured logic to actively discourage the use of condoms in countries ravaged by AIDS. "This is genocidal stupidity," Harris said. Faith trumps rational argument. Common-sense ethical intuition is blinded by religious metaphysics. In the US, 22% of the population are CERTAIN that Jesus is coming back in the next 50 years, and another 22% think that it's likely. The good news of Christ's return, though, can only occur following desperately bad news. Mushroom clouds would be welcomed. "End time thinking," Harris said, "is fundamentally hostile to creating a sustainable future." Harris was particularly critical of religious moderates who give cover to the fundamentalists by not challenging them. The moderates say that all is justified because religion gives people meaning in their life. "But what would they say to a guy who believes there's a diamond the size of a refrigerator buried in his backyard? The guy digs out there every Sunday with his family, cherishing the meaningthe quest gives them." "I've read the books," Harris said. "God is not a moderate." The Bible gives strict instructions to kill various kinds of sinners, and their relatives, and on occasion their entire towns. Yet slavery is challenged nowhere in the New or
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?
thinkahol *

Which-way detector unlocks some mystery of the double-slit experiment - 1 views

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    (PhysOrg.com) -- One of the greatest puzzles of the double-slit experiment - and quantum physics in general - is why electrons seem to act differently when being observed. While electrons traveling through a barrier with two slits create interference patterns when unobserved, these interference patterns disappear when scientists detect which slit each electron travels through. By designing a modified version of the double-slit experiment with a new "which-way" electron detector at one of the slits, a team of scientists from Italy has found a clue as to why electron behavior appears to change when being observed.
Walid Damouny

Standard model (particle physics) - 1 views

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    "By Casey Johnston | The standard model of particle physics dictates that the world is made up of sixteen types of particles divided into two types: fermions and bosons. The way these particles behave with each other shows that there are four possible kinds of interactions: electromagnetic, strong, weak, and gravitational."
thinkahol *

Quantum physics first: Physicists measure without distorting - 1 views

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    With this new experiment, the researchers have succeeded for the first time in experimentally reconstructing full trajectories which provide a description of how light particles move through the two slits and form an interference pattern. Their technique builds on a new theory of weak measurement that was developed by Yakir Aharonov's group at Tel Aviv University. Howard Wiseman of Griffith University proposed that it might be possible to measure the direction a photon (particle of light) was moving, conditioned upon where the photon is found. By combining information about the photon's direction at many different points, one could construct its entire flow pattern ie. the trajectories it takes to a screen.
thinkahol *

DNA can discern between two quantum states, research shows - 2 views

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    ScienceDaily (June 4, 2011) - Do the principles of quantum mechanics apply to biological systems? Until now, says Prof. Ron Naaman of the Institute's Chemical Physics Department (Faculty of Chemistry), both biologists and physicists have considered quantum systems and biological molecules to be like apples and oranges. But research he conducted together with scientists in Germany, which appeared recently in Science, shows that a biological molecule -- DNA -- can discern between quantum states known as spin.
thinkahol *

Color red increases the speed and strength of reactions | KurzweilAI - 1 views

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    Researchers at the University of Rochester have determined that when humans see the color red, their reactions become both faster and more forceful. The researchers measured the reactions of students in two experiments. In the first, 30 fourth-through-10th graders pinched and held open a metal clasp. Right before doing so, they read aloud their participant number written in either red or gray crayon. In the second experiment, 46 undergraduates squeezed a handgrip with their dominant hand as hard as possible when they read the word "squeeze" on a computer monitor. The word appeared on a red, blue, or gray background. In both scenarios, red significantly increased the force exerted, with participants in the red condition squeezing with greater maximum force than those in the gray or blue conditions, the researchers said. Ref.: Andrew J. Elliot, Henk Aarts, Perception of the color red enhances the force and velocity of motor output, Emotion, Vol 11(2), Apr 2011, 445-449
thinkahol *

First 'living' laser made from kidney cell - physics-math - 12 June 2011 - New Scientist - 0 views

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    It's not quite Cyclops, the sci-fi superhero from the X-Men franchise whose eyes produce destructive blasts of light, but for the first time a laser has been created using a biological cell. The human kidney cell that was used to make the laser survived the experience. In future such "living lasers" might be created inside live animals, which could potentially allow internal tissues to be imaged in unprecedented detail. It's not the first unconventional laser. Other attempts include lasers made of Jell-O and powered by nuclear reactors (see box below). But how do you go about giving a living cell this bizarre ability? Typically, a laser consists of two mirrors on either side of a gain medium - a material whose structural properties allow it to amplify light. A source of energy such as a flash tube or electrical discharge excites the atoms in the gain medium, releasing photons. Normally, these would shoot out in random directions, as in the broad beam of a flashlight, but a laser uses mirrors on either end of the gain medium to create a directed beam. As photons bounce back and forth between the mirrors, repeatedly passing through the gain medium, they stimulate other atoms to release photons of exactly the same wavelength, phase and direction. Eventually, a concentrated single-frequency beam of light erupts through one of the mirrors as laser light.
thinkahol *

Artificial hippocampal system restores long-term memory, enhances cognition | KurzweilAI - 2 views

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    Theodore Berger and his team at the USC Viterbi School of Engineering's Department of Biomedical Engineering have developed a neural prosthesis for rats that is able to restore their ability to form long-term memories after they had been pharmacologically blocked. In a dramatic demonstration, Berger blocked the ability to rats to form long-term memories by using pharmacological agents to disrupt the neural circuitry that communicates between two subregions of the hippocampus, CA1 and CA3, which interact to create long-term memory, prior research has shown. The rats were unable to remember which lever to pull to gain a reward, or could only remember for 5-10 seconds, when previously they could remember for a long period of time. The researchers then developed an artificial hippocampal system that could duplicate the pattern of interaction between CA3-CA1 interactions. Long-term memory capability returned to the pharmacologically blocked rats when the team activated the electronic device programmed to duplicate the memory-encoding function. The researchers went on to show that if a prosthetic device and its associated electrodes were implanted in animals with a normal, functioning hippocampus, the device could actually strengthen the memory being generated internally in the brain and enhance the memory capability of normal rats. "These integrated experimental modeling studies show for the first time that with sufficient information about the neural coding of memories, a neural prosthesis capable of real-time identification and manipulation of the encoding process can restore and even enhance cognitive mnemonic processes," says the paper. Next steps, according to Berger and Deadwyler, will be attempts to duplicate the rat results in primates (monkeys), with the aim of eventually creating prostheses that might help human victims of Alzheimer's disease, stroke, or injury recover function. Ref.: "A Cortical Neural Prosthesis for Restoring and Enhancing
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