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The science behind RHCs liver thread

Discussion in 'Liverpool' started by Prince Knut, Apr 30, 2016.

  1. Diego

    Diego Lone Ranger

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    #141
  2. Prince Knut

    Prince Knut GC Thread Terminator

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  3. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    Unusually loose skin helps hagfish survive shark attacks
    Slip-sliding outer covering also aids in Houdini escapes
    BY
    SUSAN MILIUS
    6:26PM, JANUARY 6, 2017
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    SAVE OUR SAGGY SKINS Remarkably loose-fitting skin could help hagfish (Eptatretus stoutii shown) survive a shark bite.

    TOM MCHUGH/SCIENCE SOURCE

    SPONSOR MESSAGE
    View the video

    NEW ORLEANS, La. – Skin that mostly hangs loose around hagfishes proves handy for living through a shark attack or wriggling through a crevice.

    The skin on hagfishes’ long, sausage-style bodies is attached in a line down the center of their backs and in flexible connections where glands release slime, explained Douglas Fudge of Chapman University in Orange, Calif. This floating skin easily slip-slides in various directions. A shark tooth can puncture the skin but not stab into the muscle below. And a shark attack is just one of the crises when loose skin can help, Fudge reported January 5 at the annual meeting of the Society for Integrative and Comparative Biology.

    the tooth readily punched through skin but slipped away from stabbing into the body of either the Atlantic (Myxine glutinosa) or Pacific (Eptatretus stoutii) hagfish species.

    Story continues after video.

    HAGFISH VS. SHARK A shark biting a long, skinny hagfish does not turn out so well for the shark. The murky cloud that suddenly appears around its head is the famed defensive slime released by hagfishes. This kind of video, showing a hagfish withstanding a crunch from shark jaws, inspired research on the possible protective power of loose hagfish skin.MUSEUM OF NEW ZEALAND/YOUTUBE

    But when the researchers glued the skin firmly to the hagfish muscle so the skin couldn’t slip, the tooth typically plunged into inner tissue. For comparison, the researchers tested lampreys, which are similarly tube-shaped but with skin well-fastened to their innards. When the guillotine dropped on them, the tooth often stabbed directly into flesh.

    The finding makes sense to Theodore Uyeno of Valdosta State University in Georgia, whose laboratory work suggests how loose skin might work in minimizing damage from shark bites. He and colleagues have tested how hard it is to puncture swatches of skin from both the Atlantic and Pacific species. As is true for many other materials, punching through a swatch of hagfish skin held taut didn’t take as long as punching through skin patches allowed to go slack, he said in a January 5 presentation at the meeting. Even a slight delay when a sharp point bears down on baggy skin might allow the hagfish to start dodging and sliming.

    But Michelle Graham, who studies locomotion in flying snakes at Virginia Tech, wondered if puncture wounds would be a drawback to such a defense. A hagfish that avoids a deep stab could still lose blood from the skin puncture. That’s true, said Fudge, but the loss doesn’t seem to be great. Hagfish have unusually low blood pressure, and video of real attacks doesn’t show great gushes.

    Hagfish blood also plays a part in another benefit of loose skin — an unusual ability to wiggle through cracks, Fudge reported in a second talk at the meeting. One of his students built an adjustable crevice and found that both Atlantic and Pacific hagfishes can contort themselves through slits only half as wide as their original body diameter. Videos show skin bulging out to the rear as the strong pinch of the opening forces blood backward.

    The cavity just under a hagfish’s skin can hold roughly a third of its blood. Forcing that reservoir backward can help shrink the body diameter. Fortunately the inner body tapers at the end, Fudge said. So as blood builds up, “they don’t explode.”

    Just by way of a change <laugh>
     
    #143
  4. Zingy

    Zingy #ziggywould

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    ****ing fascinating <doh>
     
    #144
  5. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    It wasn't supposed to be, knobhead <laugh>
     
    #145
  6. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    Dark matter still missing
    XENON100 experiment contradicts suspected signal from DAMA/LIBRA
    BY
    EMILY CONOVER
    7:00AM, JANUARY 10, 2017
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    MISPLACED MATTER A search for dark matter by the XENON100 experiment has found nothing. Photomultiplier tubes within the detector, shown above, detect light produced in interactions possibly caused by dark matter particles.

    JPIENAAR13/WIKIMEDIA COMMONS (CC BY-SA 4.0)

    SPONSOR MESSAGE
    Chalk up one more loss for physicists searching for dark matter. Scientists with the XENON100 experiment have largely ruled out another experiment’s controversial claim of detecting dark matter.

    XENON100, located in Italy’s Gran Sasso National Laboratory, aims to directly detect particles of dark matter — the unknown substance that scientists believe makes up the bulk of matter in the cosmos (SN: 11/12/16, p. 14).

    In their new analysis, published online January 3 at arXiv.org, XENON100 scientists looked for an annual variation in the rate of blips in their detector, a tank filled with 161 kilograms of liquid xenon. Such a signal could be a hallmark of Earth’s motion through a prevailing wind of dark matter particles as the planet makes its yearly jaunt around the sun. Another dark matter experiment at Gran Sasso, DAMA/LIBRA, claims to have found strong evidence of a yearly modulation, but other experiments have failed to replicate the result.

    Scientists combed over four years of data for events that could be caused by dark matter interacting with electrons in XENON100. The researchers found no evidence of an annual cycle, contradicting DAMA’s claim.

    Dark matter optimists can still cling to a caveat, though: DAMA uses a different detection material, composed of sodium iodide crystals rather than xenon. That might explain the difference between the two experiments. Future experiments will attempt to replicate DAMA’s result using the same material.
     
    #146
  7. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    Milky Way’s black hole may hurl galactic spitballs our way
    Giant gas blobs are what’s left of gravity-shredded stars
    BY
    CHRISTOPHER CROCKETT
    9:00AM, JANUARY 10, 2017
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    DUCK! Blobs of gas roughly the mass of Jupiter (several illustrated) could form near the black hole at the center of the Milky Way and shoot into intergalactic space.

    MARK A. GARLICK/CFA

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    GRAPEVINE, TEXAS — The gargantuan black hole at the center of the Milky Way is a little like an unruly kid, hurling spitballs. But unlike a child’s arsenal, these spitballs are roughly the size of a planet and can travel fast enough to shoot out of the galaxy. Some might even zip right by our solar system.

    Stars that pass too close to the black hole can be shredded by the intense gravity. Previous simulations have shown that within these strands of stellar debris, gas can clump back together into balls roughly the mass of Jupiter that are then launched away at several thousand kilometers per second. What happens to these blobs was unknown.

    About 95 percent are launched so fast that they escape the gravity of the Milky Way and fly into intergalactic space, Eden Girma, an undergraduate at Harvard University, said January 6 in a news conference at a meeting of the American Astronomical Society. Girma and James Guillochon, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, developed computer simulations to figure out the fate of these galactic spitballs. Those that don’t escape get stuck in orbits just a few hundred light-years from the black hole.

    Of those that do fly away, some could pass through our cosmic neighborhood, getting as close as about 700 light-years, said Girma. Detecting them won’t be easy. With no internal heat source, the blobs would emit only a trickle of infrared light. The best bet, she said, is to catch one as it passes between Earth and a distant star. The starlight, magnified by the gravity of the projectile, would momentarily brighten and betray the blob’s presence.

    <yikes>
     
    #147
  8. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    Bump hiding in 20-year-old data could be undiscovered particle


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    A particle collision from the ALEPH experiment that started in 1989
    Jean-Luc Caron /CERN

    By Shannon Hall

    Could old colliders point to new discoveries? An energy excess spotted in data from a 20-year-old experiment suggests so. The bump hints at the existence of a previously undetected particle, which could change our understanding of physics. Then again, it could also be a statistical fluke.

    The ALEPH particle detector at CERN near Geneva, Switzerland, switched on in July 1989. For the next 15 years, it analysed the decays of millions of Z particles created in the Large Electron-Positron (LEP) collider – located in the same tunnel that now houses the Large Hadron Collider.

    Although scientists scrutinised those decays throughout the experiment’s lifetime, they tended to look only for signals that theorists had predicted.





    In the years since, theorists have made many more predictions. So Arno Heister at CERN decided to take a second look at the old data. Without looking for anything in particular, he found a slight excess of decay products at an energy of about 30 gigaelectronvolts (GeV).


    Just as the famous Higgs boson first showed itself with a tiny bump that swelled as more data was gathered, this could signify the existence of a new particle. But this particle, unlike the Higgs boson, was not predicted by the standard model of particle physics, and so could point toward a more complex theory of nature.

    That would be a dream come true. Physicists are hungry for a model that can probe questions the standard model cannot, like why there is more matter than antimatter or what constitutes dark matter.

    Proceed with caution
    But Heister doesn’t jump to that conclusion. “I cannot tell you if it’s something really new, if it’s a statistical fluctuation, or if it’s something we didn’t understand in the standard model,” he says. “I have no clue what it could be.”

    The issue is that the statistical significance of the bump is at most 3 sigma, meaning the odds that it’s due to chance are about 1 in 740. At that level, the bump could disappear fast. Earlier this year, for example, a similar signal had physicists all abuzz before it disappeared after several months of additional data. In order to claim a discovery, particle physicists require a 5-sigma result, meaning the chance that the signal is a fluke is about 1 in 3.5 million.

    More evidence will either boost or destroy the signal. “The good news is that there are three other LEP experiments and three other LHC experiments that can all weigh in,” says Matthew Strassler from Harvard University. “So this should be settled very quickly.”

    And even if the excess turns out to be a fluke, the paper highlights an important issue, Strassler says: major colliders like the LHC may have more secrets to reveal, even within experiments that are 20 years old. Strassler hopes that the findings will urge other scientists to further examine old data. Because without a particular theory in mind, you never know what might turn up.
     
    #148
  9. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    Promise and perils of marijuana deserve more scientific scrutiny
    Limits on ability to study drug hamper efforts to weigh public health benefits, concerns
    BY
    BRUCE BOWER
    3:02PM, JANUARY 12, 2017
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    HIGH HOPES Cannabis plants such as this one yield marijuana and other substances that deserve expanded study for possible medical benefits, a large research review recommends. But negative physical and psychological effects of cannabis products can’t be ignored, the report says.

    TDFUGERE/PIXABAY

    SPONSOR MESSAGE
    Marijuana’s medical promise deserves closer, better-funded scientific scrutiny, a new state-of-the-science report concludes.

    The report, released January 12 by the National Academies of Sciences, Engineering and Medicine in Washington, D.C., calls for expanding research on potential medical applications of cannabis and its products, including marijuana and chemical components called cannabinoids.

    Big gaps in knowledge remain about health effects of cannabis use, for good or ill. Efforts to study these effects are hampered by federal classification of cannabis as a Schedule 1 drug, meaning it has no accepted medical use and a high potential for abuse. Schedule 1 status makes it difficult for researchers to access cannabis. The new report recommends reclassifying the substance to make it easier to study.

    Recommendations from the 16-member committee that authored the report come at a time of heightened acceptance of marijuana and related substances. Cannabis is a legal medical treatment in 28 states and the District of Columbia. Recreational pot use is legal in eight of those states and the District.

    “The legalization and commercialization of cannabis has allowed marketing to get ahead of science,” says Raul Gonzalez, a psychologist at Florida International University in Miami who reviewed the report before publication. While the report highlights possible medical benefits, Gonzalez notes that it also underscores negative consequences of regular cannabis use. These include certain respiratory and psychological problems.

    A 2015 survey indicated that around 22 million people in the United States ages 12 and older ingested some form of cannabis in the last month, mainly as a recreational drug. Roughly 10 percent of those people reported using cannabis solely for medical reasons and 36 percent reported a mix of recreational and medical use.

    “This growing acceptance, accessibility and use of cannabis and its derivatives have raised important public health concerns,” says committee chair Marie McCormick, a Harvard T.H. Chan School of Public Health pediatrician.

    She and her committee colleagues considered more than 10,700 abstracts of studies on cannabis’s health effects published between January 1, 1999, and August 1, 2016. The committee gave special weight to research reviews published since 2011.

    Cannabis and cannabinoids show medical potential, the report concludes. Evidence indicates that these substances substantially reduce chronic pain in adults. Cannabis derivatives ingested in pills by multiple sclerosis patients temporarily reduce self-reported muscle spasms (SN: 6/19/10, p. 16). Cannabinoids also help to prevent and lessen chemotherapy-induced nausea and vomiting in adults.

    Less conclusive evidence suggests cannabis and cannabinoids improve sleep for adults with sleep apnea, fibromyalgia, chronic pain and multiple sclerosis, the report says.

    “If cannabis was to be classified as a medicine, then it needs to be rigorously tested like all other medicines,” says pharmacologist Karen Wright of Lancaster University in England. She hopes the new report spurs researchers to develop standards for the chemical composition of cannabis products tested as possible medical treatments. Despite cannabis’s medical promise, scientists have more questions than answers about how its use influences physical and mental health.

    Encouragingly, studies reviewed by the committee suggest that smoking marijuana, unlike smoking cigarettes, does not increase the chances of developing lung, head and neck cancers. But pot’s relationship to other cancers — as well as to heart attacks, strokes and diabetes — is unclear. And few or no findings support the use of cannabis to treat Tourette’s syndrome, post-traumatic stress disorder, cancer, epilepsy (SN Online: 4/13/15) or other medical ailments.

    Evidence does not conclusively link marijuana smoking to respiratory diseases such as asthma. But regular pot use tends to accompany increased chronic bronchitis episodes and an intensified cough and phlegm production, at least until smoking stops.

    Cannabis smoke may deter infection-related inflammation in the body. But data are sparse on whether cannabis or its derivatives influence immune responses in healthy people or those with HIV.

    There are some clear downsides to consuming marijuana and related substances, the new report adds. Solid scientific support exists for a link between cannabis use and later development of psychotic disorders such as schizophrenia. A moderate relationship exists between cannabis use and the development of addictions to alcohol, tobacco and illegal drugs.

    Fairly strong evidence points to learning, memory and attention problems immediately after smoking marijuana. Limited data, however, tie pot use to academic problems, dropping out of school, unemployment or lowered income in adulthood.

    <yikes>
     
    #149
  10. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    It takes guts for a sea spider to pump blood
    These arthropods’ unusual digestive system can act like a heart and gills
    BY
    SUSAN MILIUS
    4:46PM, JANUARY 11, 2017
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    LEGGY MULTITASKERS The skinny legs of sea spiders (one shown from Antarctica) hold guts that digest food and help pump blood.

    TIMOTHY DWYER (POLARTREC 2016), COURTESY OF ARCUS

    SPONSOR MESSAGE
    NEW ORLEANS — A newfound way of delivering oxygen in animal circulatory systems depends mostly on food sloshing back and forth in the guts.

    This discovery came in sea spiders, or pycnogonids, which can look like legs in search of a body. Their spookily long legs hold stretches of digestive tract, which wouldn’t fit inside the creatures’ scrap of an abdomen. Waves of contraction sweeping up and down the leggy guts cause blood outside the guts to move too, evolutionary physiologist Art Woods of the University of Montana in Missoula said January 8 at the annual meeting of the Society for Integrative and Comparative Biology. As lumpy surges of partly digested food rise and fall, blood that has picked up oxygen by diffusion whooshes to the rest of the body, Woods proposed.

    “Essentially they use their legs like gills,” says Jon Harrison, an evolutionary physiologist at Arizona State University in Tempe, who was not involved in the research. “To my knowledge, no one had thought of this before — certainly no one has demonstrated this before.”

    The roughly 1,300 sea spider species aren’t true spiders but a closely related lineage of arthropods. They feed via a long proboscis that doesn’t punch into food but gnaws at it bit by bit and then sucks up the smaller nuggets. Those nuggets typically come from hunting or scavenging other invertebrates. Jellyfish and hydroids are some sea spiders’ favorites with occasional other snacks such as clams or sea slugs. Various sea spider species live from the tropics to the poles, and in Antarctica, sea spiders grow to a leg span wider than a dinner plate.

    Woods and colleagues were studying this polar gigantism when they began thinking through the spiders’ oxygen consumption. A sea spider’s outer covering is porous enough for oxygen to diffuse through. But the researchers calculated that mere diffusion without some kind of inner pump couldn’t meet these animals’ oxygen needs.

    Most sea spider species have a heart and, like other arthropods, an open circulatory system. The heart shoots a pulse of blood out open-ended vessels where it washes over body tissues and then flows back into the heart’s uptake plumbing.

    A sea spider heart might boost flow to such blood-hungry zones as the muscular proboscis, but the researchers didn’t see big, regular pulses of blood radiating outward through the body. Hearts probably aren’t the whole story for circulation, Woods concluded.

    The researchers also observed that there’s more oxygen in the tips of the legs. Gut activity could then drive the newly oxygenated blood up the leg toward the rest of the body. A video showed a stretch of gut bulging wide inside the leg as a dollop of food washed through, shrinking as the wake died away and then swelling again as a food wave arrived from the opposite direction. These motions inside gut tissue let the oxygen-enriched blood circulate, Woods proposed.

    To test the idea, the researchers lowered the oxygen content of water around sea spiders. The movements of the digestive tract increased, as expected if the guts had to work harder to supply oxygen. And when researchers raised the water temperature for both polar and temperate species, which revs up metabolism and increases oxygen demand, gut activity increased, too.

    Woods proposes that sea spider blood circulation by gut motion might prove to be what paleontologist Stephen Jay Gould called an exaptation, a trait with one function that over the course of evolution takes on another. Woods’ guess: The digestive system formed first and later happened into circulation.

    <yikes>
     
    #150
    * Record Points Total likes this.

  11. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    LSD’s grip on brain protein could explain drug’s long-lasting effects
    Molecular modeling called ‘first snapshot of LSD in action’
    BY
    MEGHAN ROSEN
    2:00PM, JANUARY 31, 2017
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    HALLUCINOGEN HIDEAWAY A protein that senses serotonin in the brain traps LSD (pink) inside a pocket and forms a lid (dark purple) over the opening. The lid moves aside occasionally (right), allowing LSD to escape.

    D. WACKER ET AL/CELL 2017

    SPONSOR MESSAGE
    Locked inside a human brain protein, the hallucinogenic drug LSD takes an extra-long trip.

    New X-ray crystallography images reveal how an LSD molecule gets trapped within a protein that senses serotonin, a key chemical messenger in the brain. The protein, called a serotonin receptor, belongs to a family of proteins involved in everything from perception to mood.

    The work is the first to decipher the structure of such a receptor bound to LSD, which gets snared in the protein for hours. That could explain why “acid trips” last so long, study coauthor Bryan Roth and colleagues report January 26 in Cell. It’s “the first snapshot of LSD in action,” he says. “Until now, we had no idea how it worked at the molecular level.”

    But the results might not be that relevant to people, warns Cornell University biophysicist Harel Weinstein.

    Roth’s group didn’t capture the main target of LSD, a serotonin receptor called 5-HT2A, instead imaging the related receptor 5-HT2B. That receptor is “important in rodents, but not that important in humans,” Weinstein says.

    Roth’s team has devoted decades to working on 5-HT2A, but the receptor has “thus far been impossible to crystallize,” he says. Predictions of 5-HT2A’s structure, though, are very similar to that of 5-HT2B, he says.

    LSD, or lysergic acid diethylamide, was first cooked up in a chemist’s lab in 1938. It was popular (and legal) for recreational use in the early 1960s, but the United States later banned the drug (also known as blotter, boomer, Purple Haze and electric Kool-Aid).

    It’s known for altering perception and mood — and for its unusually long-lasting effects. An acid trip can run some 15 hours, and at high doses, effects can linger for days. “It’s an extraordinarily potent drug,” says Roth, a psychiatrist and pharmacologist at the University of North Carolina School of Medicine in Chapel Hill.

    Scientists have known for decades that LSD targeted serotonin receptors in the brain. These proteins, which are also found in the intestine and elsewhere in the body, lodge within the outer membranes of nerve cells and relay chemical signals to the cells’ interiors. But no one knew exactly how LSD fit into the receptor, or why the drug was so powerful.

    Roth and colleagues’ work shows the drug hunkered deep inside a pocket of the receptor, grabbing onto an amino acid that acts like a handle to pull down a lid. It’s like a person holding the door of a storm cellar closed during a tornado, Roth says.

    When the team did additional molecular experiments, tweaking the lid’s handle so that LSD could no longer hang on, the drug slipped out of the pocket faster than when the handle was intact. That was true whether the team used receptor 5-HT2B or 5-HT2A, Roth says. (Though the researchers couldn’t crystallize 5-HT2A, they were able to grow the protein inside cells in the lab for use in their other experiments.) The results suggest that LSD’s grip on the receptor is what keeps it trapped inside. “That explains to a great extent why LSD is so potent and why it’s so long-lasting,” Roth says.

    David Nutt, a neuropsychopharmacologist at Imperial College London, agrees. He calls the work an “elegant use of molecular science.”

    Weinstein remains skeptical. The 5-HT2A receptor is the interesting one, he maintains. A structure of that protein “has been needed for a very long time.” That’s what would really help explain the hallucinogenic effects of LSD, he says.

    Ahhhhceeeeeeeeeeeeeeeeeeeeeeeeed <laugh>
     
    #151
  12. Prince Knut

    Prince Knut GC Thread Terminator

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    Up to @ page 150 now on that Penrose book. Heavy going, as you warned, with all the stuff about algorithims and whether they're natural or artificial, the Godel or Turing model(s), etc, but I can see where it's going. It does tie in completely with Harari book, Homo Dues, that I'm reading too: does the human race effectively end when we take the steps to 'Immortality' by becoming a semi (or non) biological computing machine? Will there still be a ghost in the machine when 'humans' evolve into Data from TNG? I personally think that we are our thoughts and emotions, and that is where brains in every creature has evolved from: processing chemical emotions such as fight or flight within our environment to stay long enough to reproduce.

    Question I ask though is what would Darwin himself make of all this? Is this the logical extension of evolution that we divest our DNA? 'It's life Jim, but not as we know it'...

    If you get a chance, read the Harari books (Sapiens first). I suppose it's Luddite to try and stop this, and evolution that a species that can will use its instinct to survive to cheat evolution of its entry fee - death. I just hope these super beings remember us and can travel backward in time in their new guise and capture our 'essence' and keep us in a data hologram as a sort of benign zoo. Or have they already?....:emoticon-0176-smoke

    Seems more plausible than the Anthropic Principle and Wheeler and all that; and this is where i came in. BTW, at its most fundamental, Planck like constituent (superstrings, if Greene is to be believed) is all this stuff data or analogue? Is this a moot point anyway? Is the one time I tried a tab 35 years ago still in my befuddled head? :emoticon-0175-drunk
     
    #152
  13. DirtyFrank

    DirtyFrank Well-Known Member

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    Waaaahahahaha

     
    #153
  14. Prince Knut

    Prince Knut GC Thread Terminator

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    Who gave Sisu a pair of shades? <cool>
     
    #154
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  15. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    LHC sees matter and antimatter misbehaving in alternate particle


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    Spot the baryon
    CERN/LHCb

    By Lisa Grossman

    A hint of matter and antimatter behaving differently to each other has been spotted in a new particle for the first time. If the find bears out, it could help explain the existence of all the matter in the universe, and why it was not snuffed out by antimatter long ago.

    Physicists think that the big bang should have produced equal amounts of matter and antimatter. But these contrasting particles annihilate each other in a puff of energy whenever they meet, so they should have destroyed each other long ago.

    The fact that there is enough matter in the universe today for us to exist and wonder why, means that some mechanism must have favoured matter over antimatter.

    “Today we have this complete imbalance between matter and antimatter. We have no evidence of antimatter in the universe,” says Nicola Neri of the National Institute for Nuclear Physics in Milan, Italy. “This is one of the main questions we’d like to answer.”

    One way the two could differ is by violating a rule about the way the laws of physics affect particles and antiparticles known as CP symmetry. Previously, experiments showed that CP symmetry is in fact violated in particles called mesons, which are made up of a quark and an antiquark. Those results garnered two Nobel prizes, one in 1980 and one in 2008.

    But it wasn’t enough. “The sources we’ve found so far are not sufficient to explain this huge imbalance,” Neri says.

    Keep calm and baryon
    Now, Neri and his colleagues have checked another kind of particle: baryons, which are made of three quarks and no antiquarks. Neutrons and protons, the building blocks of matter, are baryons.

    They watched for differences in the decay of baryons and their antimatter counterparts made of three antiquarks, and they were lucky. The particles decayed in a way that seems to violate CP symmetry.

    “This is the first hint, a sign that something is going on there,” Neri says.

    During the first run of the Large Hadron Collider at CERN near Geneva, between 2011 and 2012, the large international team used the LHCb experiment to watch the decay of heavy baryons called lambda-b particles, which are about six times heavier than a neutron.

    They observed about 6500 instances of lambda-b particles decaying into a proton and three particles called pions, and about 1000 instances of a different decay that included particles called kaons as well. Theory suggested that there should be a lot of CP violation in these events, but because they needed the extreme energies of the LHC to be produced, they had never been seen before.

    “It was not anticipated that we could have such a large signal yield,” Neri says. “That was a nice surprise.”

    The kaon decay looked normal. But the pion version showed a deviation from the standard predictions to a statistical significance of 3.3 sigma, meaning random fluctuations would produce a similar signal less than once every 1000 times.

    Not a chance
    Particle physicists consider that level of significance evidence that something strange is happening, but it’s not quite enough to declare discovery. That will have to wait for 5-sigma, when the odds of random fluctuations producing a similar signal are less than one in a million.

    But the LHC has been upgraded and collected more data since these measurements, and is still ramping up to its full potential. Neri expects to increase their data set by at least a factor of 10.

    And even if the signal goes away with more data, it’s still useful to be able to compare CP violation in baryons and mesons, Neri says.

    “We can do studies for the first time in baryon decays and make good comparisons with decays with similar quark transitions, and in that way get information on the underlying physics,” he says. “We are entering an era with LHCb where we can make precision measurements in CP violation in heavy baryons. You open a new series of measurements with this kind of result. That’s the excitement.”

    “It’s an important observation,” says David MacFarlane at the SLAC National Accelerator Laboratory in Menlo Park, California, who was on the team that measured CP violation in mesons. “The more systems we see CP violations in, the more chance we have to understand whether the standard model is correct, or whether there are other sources.”
     
    #155
  16. FedLadSonOfAnfield

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    Why do chemists like nitrates so much ?

    Because they're cheaper than day rates
     
    #156
    Zingy likes this.
  17. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    Great documentary about entropy on BBC 4 last night <ok>
     
    #157
  18. Milk not bear jizz

    Milk not bear jizz Grasser-In-Chief

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    Did it start coherently but slowly descend into chaos?
     
    #158
  19. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    No. The other way around <yikes>
     
    #159
  20. Red Hadron Collider

    Red Hadron Collider The Hammerhead

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    Ceres harbors homegrown organic compounds
    Data hint dwarf planet may have had habitable environment
    BY
    ELIZABETH EATON
    2:58PM, FEBRUARY 16, 2017
    please log in to view this image

    HINTS OF LIFE? Organic matter has been detected on Ceres, shown, suggesting the dwarf planet hosts the building blocks of life.

    JPL-CALTECH/NASA, UCLA, MPS, DLR, IDA

    SPONSOR MESSAGE
    Dwarf planet Ceres contains the necessary ingredients for life, new data suggest.

    NASA’s Dawn spacecraft has detected organic compounds on Ceres — the first concrete proof of organics on an object in the asteroid belt between Mars and Jupiter. This material probably originated on the dwarf planet itself, the researchers report in the Feb. 17 Science. The discovery of organic compounds, the building blocks of life, adds to the growing body of evidence that Ceres may have once had a habitable environment.

    “We’ve come to recognize that Ceres has a lot of characteristics that are intriguing for those looking at how life starts,” says Andy Rivkin, a planetary astronomer at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., who was not involved in the study.

    The Dawn probe has previously detected salts, ammonia-rich clays and water ice on Ceres, which together indicate hydrothermal activity, says study coauthor Carol Raymond, a planetary scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

    For life to begin, you need elements like carbon, hydrogen, nitrogen and oxygen, as well as a source of energy. Both the hydrothermal activity and the presence of organics point toward Ceres having once had a habitable environment, Raymond says.

    “If you have an abundance of those elements and you have an energy source,” she says, “then you’ve created sort of the soup from which life could have formed.” But study coauthor Lucy McFadden, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., stresses that the team has not actually found any signs of life on Ceres.

    Evidence of Ceres’ organic material comes from areas near Ernutet crater. Dawn picked up signs of a “fingerprint,” or spectra, consistent with organics. The pattern of wavelengths of light absorbed and reflected from these areas is similar to the pattern seen in hydrocarbons on Earth such as kerite and asphaltite. But without a sample from the surface, the team can’t say definitively what organic material is present or how it formed, says study coauthor Harry McSween, a geologist at the University of Tennessee.

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    CRATER CACHE Most of the organic compounds on Ceres have been found near the Ernutet crater, outlined in white. Purple areas indicate low concentrations of organics, and the spots of orange and yellow show higher abundance.
    JPL-CALTECH/NASA, UCLA, ASI, INAF, MPS, DLR, IDA


    The team suspects that the organics formed within Ceres’ interior and were brought to the surface by hydrothermal activity. An alternative idea — that a space rock that crashed into Ceres brought the material — is unlikely, the researchers say, because the concentration of organics is so high. An impact would have mixed organic compounds across the surface, diluting the concentration.

    Detecting organics on Ceres also has implications for how life arose on Earth, McSween says. Some researchers think that life was jump-started by asteroids and other space rocks that delivered organic compounds to the planet. Finding such organic matter on Ceres “adds some credence to that idea,” he says.
     
    #160

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