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Javier E

Seeking Dark Matter, They Detected Another Mystery - The New York Times - 0 views

  • A team of scientists hunting dark matter has recorded suspicious pings coming from a vat of liquid xenon underneath a mountain in Italy
  • If the signal is real and persists, the scientists say, it may be evidence of a species of subatomic particles called axions — long theorized to play a crucial role in keeping nature symmetrical but never seen — streaming from the sun.
  • Instead of axions, the scientists may have detected a new, unexpected property of the slippery ghostly particles called neutrinos. Yet another equally likely explanation is that their detector has been contaminated by vanishingly tiny amounts of tritium, a rare radioactive form of hydrogen.
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  • “We want to be very clear that all we are reporting is observation of an excess (a fairly significant one) and not a discovery of any kind,”
  • “I’m trying to be calm here, but it’s hard not to be hyperbolic,” said Neal Weiner, a particle theorist at New York University. “If this is real, calling it a game changer would be an understatement.”
  • Dr. Aprile’s Xenon experiment is currently the largest and most sensitive in an alphabet soup of efforts aimed at detecting and identifying dark matter
  • The best guess is that this dark matter consists of clouds of exotic subatomic particles left over from the Big Bang and known generically as WIMPs, for weakly interacting massive particles, hundreds or thousands of times more massive than a hydrogen atom.
  • The story of axions begins in 1977, when Roberto Peccei, a professor at the University of California, Los Angeles, who died on June 1, and Helen Quinn, emerita professor at Stanford, suggested a slight modification to the theory that governs strong nuclear forces, making sure that it is invariant to the direction of time, a feature that physicists consider a necessity for the universe.
  • in its most recent analysis of that experiment, the team had looked for electrons, rather than the heavier xenon nuclei, recoiling from collisions. Among other things, that could be the signature of particles much lighter than the putative WIMPs striking the xenon.
  • Simulations and calculations suggested that random events should have produced about 232 such recoils over the course of a year.
  • But from February 2017 to February 2018, the detector recorded 285, an excess of 53 recoils.
  • Dr. Aprile and her colleagues have wired a succession of vats containing liquid xenon with photomultipliers and other sensors. The hope is that her team’s device — far underground to shield it from cosmic rays and other worldly forms of interference — would spot the rare collision between a WIMP and a xenon atom. The collision should result in a flash of light and a cloud of electrical charge.
  • this modification implied the existence of a new subatomic particle. Dr. Wilczek called it the axion, and the name stuck.
  • Axions have never been detected either directly or indirectly. And the theory does not predict their mass, which makes it hard to look for them. It only predicts that they would be weird and would barely interact with regular matter
  • although they are not WIMPS, they share some of those particles’ imagined weird abilities, such as being able to float through Earth and our bodies like smoke through a screen door.
  • In order to fulfill the requirements of cosmologists, however, such dark-matter axions would need to have a mass of less than a thousandth of an electron volt in the units of mass and energy preferred by physicists
  • (By comparison, the electrons that dance around in your smartphone weigh in at half a million electron volts each.) What they lack in heft they would more than make up for in numbers.
  • That would make individual cosmic dark-matter axions too slow and ethereal to be detected by the Xenon experiment.But axions could also be produced by nuclear reactions in the sun, and those “solar axions” would have enough energy to ping the Xenon detector right where it is most sensitive
  • The other exciting, though slightly less likely, possibility is that the Xenon collaboration’s excess signals come from the wispy particles known as neutrinos, which are real, and weird, and zipping through our bodies by the trillions every second.
  • Ordinarily, these neutrinos would not contribute much to the excess of events the detector read. But they would do so if they had an intrinsic magnetism that physicists call a magnetic moment. That would give them a higher probability of interacting with the xenon and tripping the detector
  • According to the standard lore, neutrinos, which are electrically neutral, do not carry magnetism. The discovery that they did would require rewriting the rules as they apply to neutrinos.
  • That, said Dr. Weiner, would be “a very very big deal,” because it would imply that there are new fundamental particles out there to look for — new physics.
kushnerha

New Ways Into the Brain's 'Music Room' - The New York Times - 5 views

  • Every culture ever studied has been found to make music, and among the oldest artistic objects known are slender flutes carved from mammoth bone some 43,000 years ago — 24,000 years before the cave paintings of Lascaux.
  • And though the survival value that music held for our ancestors may not be as immediately obvious as the power to recognize words, Dr. Rauschecker added, “music works as a group cohesive. Music-making with other people in your tribe is a very ancient, human thing to do.”
  • devised a radical new approach to brain imaging that reveals what past studies had missed. By mathematically analyzing scans of the auditory cortex and grouping clusters of brain cells with similar activation patterns, the scientists have identified neural pathways that react almost exclusively to the sound of music — any music. It may be Bach, bluegrass, hip-hop, big band, sitar or Julie Andrews. A listener may relish the sampled genre or revile it. No matter. When a musical passage is played, a distinct set of neurons tucked inside a furrow of a listener’s auditory cortex will fire in response.Other sounds, by contrast — a dog barking, a car skidding, a toilet flushing — leave the musical circuits unmoved.
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  • “Why do we have music?” Dr. Kanwisher said in an interview. “Why do we enjoy it so much and want to dance when we hear it? How early in development can we see this sensitivity to music, and is it tunable with experience? These are the really cool first-order questions we can begin to address.”
  • Dr. McDermott said the new method could be used to computationally dissect any scans from a functional magnetic resonance imaging device, or F.M.R.I. — the trendy workhorse of contemporary neuroscience — and so may end up divulging other hidden gems of cortical specialization. As proof of principle, the researchers showed that their analytical protocol had detected a second neural pathway in the brain for which scientists already had evidence — this one tuned to the sounds of human speech.
  • Importantly, the M.I.T. team demonstrated that the speech and music circuits are in different parts of the brain’s sprawling auditory cortex, where all sound signals are interpreted, and that each is largely deaf to the other’s sonic cues, although there is some overlap when it comes to responding to songs with lyrics.
  • In fact, Dr. Rauschecker said, music sensitivity may be more fundamental to the human brain than is speech perception. “There are theories that music is older than speech or language,” he said. “Some even argue that speech evolved from music.”
  • , many researchers had long assumed that the human brain must be equipped with some sort of music room, a distinctive piece of cortical architecture dedicated to detecting and interpreting the dulcet signals of song. Yet for years, scientists failed to find any clear evidence of a music-specific domain through conventional brain-scanning technology
  • when previous neuroscientists failed to find any anatomically distinct music center in the brain, they came up with any number of rationales to explain the results.“The story was, oh, what’s special about music perception is how it recruits areas from all over the brain, how it draws on the motor system, speech circuitry, social understanding, and brings it all together,” she said. Some researchers dismissed music as “auditory cheesecake,” a pastime that co-opted other essential communicative urges. “This paper says, no, when you peer below the cruder level seen with some methodologies, you find very specific circuitry that responds to music over speech.”
  • The researchers wondered if the auditory system might be similarly organized to make sense of the soundscape through a categorical screen. If so, what would the salient categories be? What are the aural equivalents of a human face or a human leg — sounds or sound elements so essential the brain assigns a bit of gray matter to the task of detecting them?
  • Focusing on the brain’s auditory region — located, appropriately enough, in the temporal lobes right above the ears — the scientists analyzed voxels, or three-dimensional pixels, of the images mathematically to detect similar patterns of neuronal excitement or quietude.“The strength of our method is that it’s hypothesis-neutral,” Dr. McDermott said. “We just present a bunch of sounds and let the data do the talking.”
  • Matching sound clips to activation patterns, the researchers determined that four of the patterns were linked to general physical properties of sound, like pitch and frequency. The fifth traced the brain’s perception of speech, and for the sixth the data turned operatic, disclosing a neuronal hot spot in the major crevice, or sulcus, of the auditory cortex that attended to every music clip the researchers had played.
  • “The sound of a solo drummer, whistling, pop songs, rap, almost everything that has a musical quality to it, melodic or rhythmic, would activate it,” Dr. Norman-Haignere said. “That’s one reason the result surprised us. The signals of speech are so much more homogeneous.”
  • The researchers have yet to determine exactly which acoustic features of music stimulate its dedicated pathway. The relative constancy of a musical note’s pitch? Its harmonic overlays? Even saying what music is can be tricky.
cvanderloo

3 medical innovations fueled by COVID-19 that will outlast the pandemic - 0 views

  • When COVID-19 struck, mRNA vaccines in particular were ready to be put to a real-world test. The 94% efficacy of the mRNA vaccines surpassed health officials’ highest expectations.
  • DNA and mRNA vaccines offer huge advantages over traditional types of vaccines, since they use only genetic code from a pathogen – rather than the entire virus or bacteria.
  • Gene-based vaccines also produce precise and effective immune responses. They stimulate not only antibodies that block an infection, but also a strong T cell response that can clear an infection if one occurs.
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  • These devices can measure a person’s temperature, heart rate, level of activity and other biometrics. With this information, researchers have been able to track and detect COVID-19 infections even before people notice they have any symptoms.
  • Wearables can detect symptoms of COVID-19 or other illnesses before symptoms are noticeable. While they have proved to be capable of detecting sickness early, the symptoms wearables detect are not unique to COVID-19.
  • So a logical way to look for new drugs to treat a specific disease is to study individual genes and proteins that are directly affected by that disease.
  • But this idea of mapping the protein interactions of diseases to look for novel drug targets doesn’t apply just to the coronavirus. We have now used this approach on other pathogens as well as other diseases including cancer, neurodegenerative and psychiatric disorders.
Javier E

Wine-tasting: it's junk science | Life and style | The Observer - 0 views

  • google_ad_client = 'ca-guardian_js'; google_ad_channel = 'lifeandstyle'; google_max_num_ads = '3'; // Comments Click here to join the discussion. We can't load the discussion on guardian.co.uk because you don't have JavaScript enabled. if (!!window.postMessage) { jQuery.getScript('http://discussion.guardian.co.uk/embed.js') } else { jQuery('#d2-root').removeClass('hd').html( '' + 'Comments' + 'Click here to join the discussion.We can\'t load the ' + 'discussion on guardian.co.uk ' + 'because your web browser does not support all the features that we ' + 'need. If you cannot upgrade your browser to a newer version, you can ' + 'access the discussion ' + 'here.' ); } Wor
  • Hodgson approached the organisers of the California State Fair wine competition, the oldest contest of its kind in North America, and proposed an experiment for their annual June tasting sessions.Each panel of four judges would be presented with their usual "flight" of samples to sniff, sip and slurp. But some wines would be presented to the panel three times, poured from the same bottle each time. The results would be compiled and analysed to see whether wine testing really is scientific.
  • Results from the first four years of the experiment, published in the Journal of Wine Economics, showed a typical judge's scores varied by plus or minus four points over the three blind tastings. A wine deemed to be a good 90 would be rated as an acceptable 86 by the same judge minutes later and then an excellent 94.
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  • Hodgson's findings have stunned the wine industry. Over the years he has shown again and again that even trained, professional palates are terrible at judging wine."The results are disturbing," says Hodgson from the Fieldbrook Winery in Humboldt County, described by its owner as a rural paradise. "Only about 10% of judges are consistent and those judges who were consistent one year were ordinary the next year."Chance has a great deal to do with the awards that wines win."
  • French academic Frédéric Brochet tested the effect of labels in 2001. He presented the same Bordeaux superior wine to 57 volunteers a week apart and in two different bottles – one for a table wine, the other for a grand cru.The tasters were fooled.When tasting a supposedly superior wine, their language was more positive – describing it as complex, balanced, long and woody. When the same wine was presented as plonk, the critics were more likely to use negatives such as weak, light and flat.
  • In 2011 Professor Richard Wiseman, a psychologist (and former professional magician) at Hertfordshire University invited 578 people to comment on a range of red and white wines, varying from £3.49 for a claret to £30 for champagne, and tasted blind.People could tell the difference between wines under £5 and those above £10 only 53% of the time for whites and only 47% of the time for reds. Overall they would have been just as a successful flipping a coin to guess.
  • why are ordinary drinkers and the experts so poor at tasting blind? Part of the answer lies in the sheer complexity of wine.For a drink made by fermenting fruit juice, wine is a remarkably sophisticated chemical cocktail. Dr Bryce Rankine, an Australian wine scientist, identified 27 distinct organic acids in wine, 23 varieties of alcohol in addition to the common ethanol, more than 80 esters and aldehydes, 16 sugars, plus a long list of assorted vitamins and minerals that wouldn't look out of place on the ingredients list of a cereal pack. There are even harmless traces of lead and arsenic that come from the soil.
  • "People underestimate how clever the olfactory system is at detecting aromas and our brain is at interpreting them," says Hutchinson."The olfactory system has the complexity in terms of its protein receptors to detect all the different aromas, but the brain response isn't always up to it. But I'm a believer that everyone has the same equipment and it comes down to learning how to interpret it." Within eight tastings, most people can learn to detect and name a reasonable range of aromas in wine
  • People struggle with assessing wine because the brain's interpretation of aroma and bouquet is based on far more than the chemicals found in the drink. Temperature plays a big part. Volatiles in wine are more active when wine is warmer. Serve a New World chardonnay too cold and you'll only taste the overpowering oak. Serve a red too warm and the heady boozy qualities will be overpowering.
  • Colour affects our perceptions too. In 2001 Frédérick Brochet of the University of Bordeaux asked 54 wine experts to test two glasses of wine – one red, one white. Using the typical language of tasters, the panel described the red as "jammy' and commented on its crushed red fruit.The critics failed to spot that both wines were from the same bottle. The only difference was that one had been coloured red with a flavourless dye
  • Other environmental factors play a role. A judge's palate is affected by what she or he had earlier, the time of day, their tiredness, their health – even the weather.
  • Robert Hodgson is determined to improve the quality of judging. He has developed a test that will determine whether a judge's assessment of a blind-tasted glass in a medal competition is better than chance. The research will be presented at a conference in Cape Town this year. But the early findings are not promising."So far I've yet to find someone who passes," he says.
Javier E

How Did Consciousness Evolve? - The Atlantic - 0 views

  • Theories of consciousness come from religion, from philosophy, from cognitive science, but not so much from evolutionary biology. Maybe that’s why so few theories have been able to tackle basic questions such as: What is the adaptive value of consciousness? When did it evolve and what animals have it?
  • The Attention Schema Theory (AST), developed over the past five years, may be able to answer those questions.
  • The theory suggests that consciousness arises as a solution to one of the most fundamental problems facing any nervous system: Too much information constantly flows in to be fully processed. The brain evolved increasingly sophisticated mechanisms for deeply processing a few select signals at the expense of others, and in the AST, consciousness is the ultimate result of that evolutionary sequence
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  • Even before the evolution of a central brain, nervous systems took advantage of a simple computing trick: competition.
  • It coordinates something called overt attention – aiming the satellite dishes of the eyes, ears, and nose toward anything important.
  • Selective enhancement therefore probably evolved sometime between hydras and arthropods—between about 700 and 600 million years ago, close to the beginning of complex, multicellular life
  • The next evolutionary advance was a centralized controller for attention that could coordinate among all senses. In many animals, that central controller is a brain area called the tectum
  • At any moment only a few neurons win that intense competition, their signals rising up above the noise and impacting the animal’s behavior. This process is called selective signal enhancement, and without it, a nervous system can do almost nothing.
  • All vertebrates—fish, reptiles, birds, and mammals—have a tectum. Even lampreys have one, and they appeared so early in evolution that they don’t even have a lower jaw. But as far as anyone knows, the tectum is absent from all invertebrates
  • According to fossil and genetic evidence, vertebrates evolved around 520 million years ago. The tectum and the central control of attention probably evolved around then, during the so-called Cambrian Explosion when vertebrates were tiny wriggling creatures competing with a vast range of invertebrates in the sea.
  • The tectum is a beautiful piece of engineering. To control the head and the eyes efficiently, it constructs something called an internal model, a feature well known to engineers. An internal model is a simulation that keeps track of whatever is being controlled and allows for predictions and planning.
  • The tectum’s internal model is a set of information encoded in the complex pattern of activity of the neurons. That information simulates the current state of the eyes, head, and other major body parts, making predictions about how these body parts will move next and about the consequences of their movement
  • In fish and amphibians, the tectum is the pinnacle of sophistication and the largest part of the brain. A frog has a pretty good simulation of itself.
  • With the evolution of reptiles around 350 to 300 million years ago, a new brain structure began to emerge – the wulst. Birds inherited a wulst from their reptile ancestors. Mammals did too, but our version is usually called the cerebral cortex and has expanded enormously
  • The cortex also takes in sensory signals and coordinates movement, but it has a more flexible repertoire. Depending on context, you might look toward, look away, make a sound, do a dance, or simply store the sensory event in memory in case the information is useful for the future.
  • The most important difference between the cortex and the tectum may be the kind of attention they control. The tectum is the master of overt attention—pointing the sensory apparatus toward anything important. The cortex ups the ante with something called covert attention. You don’t need to look directly at something to covertly attend to it. Even if you’ve turned your back on an object, your cortex can still focus its processing resources on it
  • The cortex needs to control that virtual movement, and therefore like any efficient controller it needs an internal model. Unlike the tectum, which models concrete objects like the eyes and the head, the cortex must model something much more abstract. According to the AST, it does so by constructing an attention schema—a constantly updated set of information that describes what covert attention is doing moment-by-moment and what its consequences are
  • Covert attention isn’t intangible. It has a physical basis, but that physical basis lies in the microscopic details of neurons, synapses, and signals. The brain has no need to know those details. The attention schema is therefore strategically vague. It depicts covert attention in a physically incoherent way, as a non-physical essence
  • this, according to the theory, is the origin of consciousness. We say we have consciousness because deep in the brain, something quite primitive is computing that semi-magical self-description.
  • I’m reminded of Teddy Roosevelt’s famous quote, “Do what you can with what you have where you are.” Evolution is the master of that kind of opportunism. Fins become feet. Gill arches become jaws. And self-models become models of others. In the AST, the attention schema first evolved as a model of one’s own covert attention. But once the basic mechanism was in place, according to the theory, it was further adapted to model the attentional states of others, to allow for social prediction. Not only could the brain attribute consciousness to itself, it began to attribute consciousness to others.
  • In the AST’s evolutionary story, social cognition begins to ramp up shortly after the reptilian wulst evolved. Crocodiles may not be the most socially complex creatures on earth, but they live in large communities, care for their young, and can make loyal if somewhat dangerous pets.
  • If AST is correct, 300 million years of reptilian, avian, and mammalian evolution have allowed the self-model and the social model to evolve in tandem, each influencing the other. We understand other people by projecting ourselves onto them. But we also understand ourselves by considering the way other people might see us.
  • t the cortical networks in the human brain that allow us to attribute consciousness to others overlap extensively with the networks that construct our own sense of consciousness.
  • Language is perhaps the most recent big leap in the evolution of consciousness. Nobody knows when human language first evolved. Certainly we had it by 70 thousand years ago when people began to disperse around the world, since all dispersed groups have a sophisticated language. The relationship between language and consciousness is often debated, but we can be sure of at least this much: once we developed language, we could talk about consciousness and compare notes
  • Maybe partly because of language and culture, humans have a hair-trigger tendency to attribute consciousness to everything around us. We attribute consciousness to characters in a story, puppets and dolls, storms, rivers, empty spaces, ghosts and gods. Justin Barrett called it the Hyperactive Agency Detection Device, or HADD
  • the HADD goes way beyond detecting predators. It’s a consequence of our hyper-social nature. Evolution turned up the amplitude on our tendency to model others and now we’re supremely attuned to each other’s mind states. It gives us our adaptive edge. The inevitable side effect is the detection of false positives, or ghosts.
summertyler

What Faces Can't Tell Us - NYTimes.com - 0 views

  • CAN you detect someone’s emotional state just by looking at his face?
  • seems like it
  • Hundreds of scientific studies support the idea that the face is a kind of emotional beacon, clearly and universally signaling the full array of human sentiments
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  • software to identify consumers’ moods
  • this assumption is wrong
  • human facial expressions, viewed on their own, are not universally understood
  • look at photographs of facial expressions (smiling, scowling and so on) and match them to a limited set of emotion words (happiness, anger and so on) or to stories with phrases like “Her husband recently died.” Most subjects, even those from faraway cultures with little contact with Western civilization, were extremely good at this task, successfully matching the photos most of the time.
  • this research method was flawed
  • with a preselected set of emotion words, these experiments had inadvertently “primed” the subjects — in effect, hinting at the answers — and thus skewed the results
  • asked to freely describe the emotion on a face (or to view two faces and answer yes or no as to whether they expressed the same emotion). The subjects’ performance plummeted
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    Detecting emotions
katrinaskibicki

Revolutionary discovery: Scientists find gravitational waves Einstein predicted - 0 views

  • For the first time ever, scientists have directly detected gravitational waves, bizarre ripples in space-time foreseen by Einstein a century ago. The discovery was the final, acid test of Einstein’s general theory of relativity.
  • Einstein has been proven right – again.For the first time ever, scientists have directly detected gravitational waves, bizarre ripples in space-time foreseen by Einstein a century ago. The discovery was the final, acid test of Einstein’s celebrated general theory of relativity, and once again Einstein’s genius held up to scrutiny.
  • The waves in question arose during the close approach of two black holes some 1.3 billion years ago, when multicellular life began to spread on Earth. Traveling at the speed of light, the waves reached our planet in September -- precisely when a observatory built to detect them was emerging from a long hiatus.
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  • When scientists first saw the data suggesting that they’d captured a gravitational wave, they thought the results seemed to good to be true. Past claims of gravitational waves have proven unreliable, and there are many possible sources of error.
  • Gravitational waves confirmedAstrophysicists have announced the discovery of gravitational waves, ripples that travel at the speed of light through the fabric of space-time. A 1916 theory of Albert Einstein’s predicted their existence. .oembed-asset-photo-image { width: 100%; }
  •  
    A new scientific discovery shows that Einstein's predictions were correct, yet again!
Javier E

The Disease Detective - The New York Times - 1 views

  • What’s startling is how many mystery infections still exist today.
  • More than a third of acute respiratory illnesses are idiopathic; the same is true for up to 40 percent of gastrointestinal disorders and more than half the cases of encephalitis (swelling of the brain).
  • Up to 20 percent of cancers and a substantial portion of autoimmune diseases, including multiple sclerosis and rheumatoid arthritis, are thought to have viral triggers, but a vast majority of those have yet to be identified.
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  • Globally, the numbers can be even worse, and the stakes often higher. “Say a person comes into the hospital in Sierra Leone with a fever and flulike symptoms,” DeRisi says. “After a few days, or a week, they die. What caused that illness? Most of the time, we never find out. Because if the cause isn’t something that we can culture and test for” — like hepatitis, or strep throat — “it basically just stays a mystery.”
  • It would be better, DeRisi says, to watch for rare cases of mystery illnesses in people, which often exist well before a pathogen gains traction and is able to spread.
  • Based on a retrospective analysis of blood samples, scientists now know that H.I.V. emerged nearly a dozen times over a century, starting in the 1920s, before it went global.
  • Zika was a relatively harmless illness before a single mutation, in 2013, gave the virus the ability to enter and damage brain cells.
  • The beauty of this approach” — running blood samples from people hospitalized all over the world through his system, known as IDseq — “is that it works even for things that we’ve never seen before, or things that we might think we’ve seen but which are actually something new.”
  • In this scenario, an undiscovered or completely new virus won’t trigger a match but will instead be flagged. (Even in those cases, the mystery pathogen will usually belong to a known virus family: coronaviruses, for instance, or filoviruses that cause hemorrhagic fevers like Ebola and Marburg.)
  • And because different types of bacteria require specific conditions in order to grow, you also need some idea of what you’re looking for in order to find it.
  • The same is true of genomic sequencing, which relies on “primers” designed to match different combinations of nucleotides (the building blocks of DNA and RNA).
  • Even looking at a slide under a microscope requires staining, which makes organisms easier to see — but the stains used to identify bacteria and parasites, for instance, aren’t the same.
  • The practice that DeRisi helped pioneer to skirt this problem is known as metagenomic sequencing
  • Unlike ordinary genomic sequencing, which tries to spell out the purified DNA of a single, known organism, metagenomic sequencing can be applied to a messy sample of just about anything — blood, mud, seawater, snot — which will often contain dozens or hundreds of different organisms, all unknown, and each with its own DNA. In order to read all the fragmented genetic material, metagenomic sequencing uses sophisticated software to stitch the pieces together by matching overlapping segments.
  • The assembled genomes are then compared against a vast database of all known genomic sequences — maintained by the government-run National Center for Biotechnology Information — making it possible for researchers to identify everything in the mix
  • Traditionally, the way that scientists have identified organisms in a sample is to culture them: Isolate a particular bacterium (or virus or parasite or fungus); grow it in a petri dish; and then examine the result under a microscope, or use genomic sequencing, to understand just what it is. But because less than 2 percent of bacteria — and even fewer viruses — can be grown in a lab, the process often reveals only a tiny fraction of what’s actually there. It’s a bit like planting 100 different kinds of seeds that you found in an old jar. One or two of those will germinate and produce a plant, but there’s no way to know what the rest might have grown into.
  • Such studies have revealed just how vast the microbial world is, and how little we know about it
  • “The selling point for researchers is: ‘Look, this technology lets you investigate what’s happening in your clinic, whether it’s kids with meningitis or something else,’” DeRisi said. “We’re not telling you what to do with it. But it’s also true that if we have enough people using this, spread out all around the world, then it does become a global network for detecting emerging pandemics
  • One study found more than 1,000 different kinds of viruses in a tiny amount of human stool; another found a million in a couple of pounds of marine sediment. And most were organisms that nobody had seen before.
  • After the Biohub opened in 2016, one of DeRisi’s goals was to turn metagenomics from a rarefied technology used by a handful of elite universities into something that researchers around the world could benefit from
  • metagenomics requires enormous amounts of computing power, putting it out of reach of all but the most well-funded research labs. The tool DeRisi created, IDseq, made it possible for researchers anywhere in the world to process samples through the use of a small, off-the-shelf sequencer, much like the one DeRisi had shown me in his lab, and then upload the results to the cloud for analysis.
  • he’s the first to make the process so accessible, even in countries where lab supplies and training are scarce. DeRisi and his team tested the chemicals used to prepare DNA for sequencing and determined that using as little as half the recommended amount often worked fine. They also 3-D print some of the labs’ tools and replacement parts, and offer ongoing training and tech support
  • The metagenomic analysis itself — normally the most expensive part of the process — is provided free.
  • But DeRisi’s main innovation has been in streamlining and simplifying the extraordinarily complex computational side of metagenomics
  • IDseq is also fast, capable of doing analyses in hours that would take other systems weeks.
  • “What IDseq really did was to marry wet-lab work — accumulating samples, processing them, running them through a sequencer — with the bioinformatic analysis,”
  • “Without that, what happens in a lot of places is that the researcher will be like, ‘OK, I collected the samples!’ But because they can’t analyze them, the samples end up in the freezer. The information just gets stuck there.”
  • Meningitis itself isn’t a disease, just a description meaning that the tissues around the brain and spinal cord have become inflamed. In the United States, bacterial infections can cause meningitis, as can enteroviruses, mumps and herpes simplex. But a high proportion of cases have, as doctors say, no known etiology: No one knows why the patient’s brain and spinal tissues are swelling.
  • When Saha and her team ran the mystery meningitis samples through IDseq, though, the result was surprising. Rather than revealing a bacterial cause, as expected, a third of the samples showed signs of the chikungunya virus — specifically, a neuroinvasive strain that was thought to be extremely rare. “At first we thought, It cannot be true!” Saha recalls. “But the moment Joe and I realized it was chikungunya, I went back and looked at the other 200 samples that we had collected around the same time. And we found the virus in some of those samples as well.”
  • Until recently, chikungunya was a comparatively rare disease, present mostly in parts of Central and East Africa. “Then it just exploded through the Caribbean and Africa and across Southeast Asia into India and Bangladesh,” DeRisi told me. In 2011, there were zero cases of chikungunya reported in Latin America. By 2014, there were a million.
  • Chikungunya is a mosquito-borne virus, but when DeRisi and Saha looked at the results from IDseq, they also saw something else: a primate tetraparvovirus. Primate tetraparvoviruses are almost unknown in humans, and have been found only in certain regions. Even now, DeRisi is careful to note, it’s not clear what effect the virus has on people. “Maybe it’s dangerous, maybe it isn’t,” DeRisi says. “But I’ll tell you what: It’s now on my radar.
  • it reveals a landscape of potentially dangerous viruses that we would otherwise never find out about. “What we’ve been missing is that there’s an entire universe of pathogens out there that are causing disease in humans,” Imam notes, “ones that we often don’t even know exist.”
  • “The plan was, Let’s let researchers around the world propose studies, and we’ll choose 10 of them to start,” DeRisi recalls. “We thought we’d get, like, a couple dozen proposals, and instead we got 350.”
  • Metagenomic sequencing is especially good at what scientists call “environmental sampling”: identifying, say, every type of bacteria present in the gut microbiome, or in a teaspoon of seawater.
  • “When you draw blood from someone who has a fever in Ghana, you really don’t know very much about what would normally be in their blood without fever — let alone about other kinds of contaminants in the environment. So how do you interpret the relevance of all the things you’re seeing?”
  • Such criticisms have led some to say that metagenomics simply isn’t suited to the infrastructure of developing countries. Along with the problem of contamination, many labs struggle to get the chemical reagents needed for sequencing, either because of the cost or because of shipping and customs holdups
  • we’re less likely to be caught off-guard. “With Ebola, there’s always an issue: Where’s the virus hiding before it breaks out?” DeRisi explains. “But also, once we start sampling people who are hospitalized more widely — meaning not just people in Northern California or Boston, but in Uganda, and Sierra Leone, and Indonesia — the chance of disastrous surprises will go down. We’ll start seeing what’s hidden.”
knudsenlu

A Tantalizing Signal From the Early Universe - The Atlantic - 0 views

  • Near the beginning, not long after the Big Bang, the universe was a cold and dark place swirling with invisible gas, mostly hydrogen and helium. Over millions of years, gravity pulled some of this primordial gas into pockets. The pockets eventually became so dense they collapsed under their own weight and ignited, flooding the darkness with ultraviolet radiation. These were the very first stars in the universe, flashing into existence like popcorn kernels unfurling in the hot oil of an empty pan.
  • Everything flowed from this cosmic dawn. The first stars illuminated the universe, collapsed into the black holes that keep galaxies together, and produced the heavy elements that would make planets and moons and the human beings that evolved to gaze upon it all.
  • Astronomers said Wednesday they have found, for the first time, evidence of the earliest stars.
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  • This epoch in our cosmic history has long fascinated scientists. They hoped that someday, using technology that was calibrated just right, they could detect faint signals from that moment. Now, they think they’ve done it.
  • The nature of this signal suggests a new estimate for when the first stars emerged: about 180 million years after the Big Bang, slightly earlier than many scientists expected, but still within the expectations of theoretical models.
  • The nature of the radio waves Bowman and his colleagues detected mostly matches theoretical predictions, but not everything lines up. When they tuned their instrument to listen to the frequency for hydrogen gas that models predicted, they didn’t hear anything. When they decided to search in a lower range, they got it. But the signal they found was stronger than expected. That meant that the hydrogen gas in the early universe was much much colder—perhaps nearly twice as cold—than previously estimated.
  • Bowman says other teams around the world have been working to build and design instruments to detect this signal from the early universe, and he expects they should be able to confirm the results in the coming months.
karenmcgregor

Unraveling the Mysteries of Wireshark: A Beginner's Guide - 2 views

In the vast realm of computer networking, understanding the flow of data packets is crucial. Whether you're a seasoned network administrator or a curious enthusiast, the tool known as Wireshark hol...

education student university assignment help packet tracer

started by karenmcgregor on 14 Mar 24 no follow-up yet
Javier E

Which Is Bigger: A Human Brain Or The Universe? : Krulwich Wonders... : NPR - 0 views

  • If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.
  • If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.
  • "The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.
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  • If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.
  • "The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.
  • If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.
  • "The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.
  • "It's beyond our intellectual limits as a species. Put yourself into the position
  • "The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.
  • "The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.
  • "The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.
  • If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.
  • "The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.
  • There are philosophers and scientists who say we will never understand the universe, we can't fathom the endless details or make good sense of the whole. We can try, but the universe is too big. The writer John Updike once explained the argument this way to reporter Jim Holt: "It's beyond our intellectual limits as a species. Put yourself into the position of a dog. A dog is responsive, shows intuition, looks at us with eyes behind which there is intelligence of a sort, and yet a dog must not understand most of the things it sees people doing. It must have no idea how they invented, say, the internal combustion engine. So maybe what we need to do is imagine that we're dogs and that there are realms that go beyond our understanding."
  • So does the universe get the crown?
  • Carl Sagan thought that we humans are good at finding patterns in nature, and if we know the rules, we can skip the details and understand the outline, the essence. It's not necessary for us to know everything. The problem is we don't know how many rules the cosmos has.
  • et the brain has its champions. "Consider the human brain," says physicist Sir Roger Penrose. "If you look at the entire physical cosmos, our brains are a tiny, tiny part of it. But they're the most perfectly organized part. Compared to the complexity of a brain, a galaxy is just an inert lump
  • my hunch is the universe will still outwit us, will still be "too wonderful" to be decoded, because we are, in the end, so much smaller than it is. And that's not a bad thing. To my mind, it's the search that matters, that sharpens us, gives us something noble to do.
  • Steven Weinberg famously said, "The effort to understand the universe is one of the very few things that lifts human life a little above the level of farce, and gives it some of the grace of tragedy."
anonymous

Errol Morris: The Thinking Man's Detective | Arts & Culture | Smithsonian Magazine - 0 views

  • To illustrate the near-impossibility of establishing veracity in photography he engaged in what might seem like a mad, hopeless enterprise: to see whether the cannonballs were initially on the road or placed there—posed for ideological impact. An investigation that involved him going halfway around the world to the Crimea to find the road and subsequently interviewing “shadow experts” on the time of day each photograph might have been shot. As one commenter wrote: “Don’t miss the excursus on the use of albatross eggs to provide the albumen for photo emulsions in early film developing. Or the meditation on Descartes’ Meditations. Or the succinct and devastating deconstruction of deconstructionists’ dim witted view of truth (just because we can’t necessarily know it, they rashly conclude it doesn’t exist). This leads to his critique of the correlative misreading of the film Rashomon [it’s not an ‘all points of view are equally valid’ manifesto] and his desire, expressed in a footnote, for a Rashomon about Rashomon.”
Javier E

Lies, Damned Lies, and Medical Science - Magazine - The Atlantic - 0 views

  • How should we choose among these dueling, high-profile nutritional findings? Ioannidis suggests a simple approach: ignore them all.
  • even if a study managed to highlight a genuine health connection to some nutrient, you’re unlikely to benefit much from taking more of it, because we consume thousands of nutrients that act together as a sort of network, and changing intake of just one of them is bound to cause ripples throughout the network that are far too complex for these studies to detect, and that may be as likely to harm you as help you
  • studies report average results that typically represent a vast range of individual outcomes.
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  • studies usually detect only modest effects that merely tend to whittle your chances of succumbing to a particular disease from small to somewhat smaller
  • The odds that anything useful will survive from any of these studies are poor,” says Ioannidis—dismissing in a breath a good chunk of the research into which we sink about $100 billion a year in the United States alone.
  • nutritional studies aren’t the worst. Drug studies have the added corruptive force of financial conflict of interest.
  • Even when the evidence shows that a particular research idea is wrong, if you have thousands of scientists who have invested their careers in it, they’ll continue to publish papers on it,” he says. “It’s like an epidemic, in the sense that they’re infected with these wrong ideas, and they’re spreading it to other researchers through journals.
  • Nature, the grande dame of science journals, stated in a 2006 editorial, “Scientists understand that peer review per se provides only a minimal assurance of quality, and that the public conception of peer review as a stamp of authentication is far from the truth.
  • The ultimate protection against research error and bias is supposed to come from the way scientists constantly retest each other’s results—except they don’t. Only the most prominent findings are likely to be put to the test, because there’s likely to be publication payoff in firming up the proof, or contradicting it.
  • even for medicine’s most influential studies, the evidence sometimes remains surprisingly narrow. Of those 45 super-cited studies that Ioannidis focused on, 11 had never been retested
  • even when a research error is outed, it typically persists for years or even decades.
  • much, perhaps even most, of what doctors do has never been formally put to the test in credible studies, given that the need to do so became obvious to the field only in the 1990s
  • Other meta-research experts have confirmed that similar issues distort research in all fields of science, from physics to economics (where the highly regarded economists J. Bradford DeLong and Kevin Lang once showed how a remarkably consistent paucity of strong evidence in published economics studies made it unlikely that any of them were right
  • His PLoS Medicine paper is the most downloaded in the journal’s history, and it’s not even Ioannidis’s most-cited work
  • while his fellow researchers seem to be getting the message, he hasn’t necessarily forced anyone to do a better job. He fears he won’t in the end have done much to improve anyone’s health. “There may not be fierce objections to what I’m saying,” he explains. “But it’s difficult to change the way that everyday doctors, patients, and healthy people think and behave.”
  • “Usually what happens is that the doctor will ask for a suite of biochemical tests—liver fat, pancreas function, and so on,” she tells me. “The tests could turn up something, but they’re probably irrelevant. Just having a good talk with the patient and getting a close history is much more likely to tell me what’s wrong.” Of course, the doctors have all been trained to order these tests, she notes, and doing so is a lot quicker than a long bedside chat. They’re also trained to ply the patient with whatever drugs might help whack any errant test numbers back into line.
  • What they’re not trained to do is to go back and look at the research papers that helped make these drugs the standard of care. “When you look the papers up, you often find the drugs didn’t even work better than a placebo. And no one tested how they worked in combination with the other drugs,” she says. “Just taking the patient off everything can improve their health right away.” But not only is checking out the research another time-consuming task, patients often don’t even like it when they’re taken off their drugs, she explains; they find their prescriptions reassuring.
  • Already feeling that they’re fighting to keep patients from turning to alternative medical treatments such as homeopathy, or misdiagnosing themselves on the Internet, or simply neglecting medical treatment altogether, many researchers and physicians aren’t eager to provide even more reason to be skeptical of what doctors do—not to mention how public disenchantment with medicine could affect research funding.
  • We could solve much of the wrongness problem, Ioannidis says, if the world simply stopped expecting scientists to be right. That’s because being wrong in science is fine, and even necessary—as long as scientists recognize that they blew it, report their mistake openly instead of disguising it as a success, and then move on to the next thing, until they come up with the very occasional genuine breakthrough
  • Science is a noble endeavor, but it’s also a low-yield endeavor,” he says. “I’m not sure that more than a very small percentage of medical research is ever likely to lead to major improvements in clinical outcomes and quality of life. We should be very comfortable with that fact.”
paisleyd

The Origins of Religion: How Supernatural Beliefs Evolved - 0 views

  • specifically, why such beliefs even exist in the first place.
  • how early humans interacted with their natural environment
  • All of a sudden, you see the grasses in front of you rustling. What do you do? Do you stop and think about what might be causing the rustling (the wind or a lion, for example), or do you immediately take some kind of action?
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  • People who took their time got selected out,
  • hypersensitive agency-detecting device, or HADD,
  • facilitated the rapid decision-making process that humans had to go through when they heard a rustling in the grass. (Lions act of their own accord. Better run.)
  • HADD may have planted the seeds for religious thought.
  • humans started attributing agency to things that really didn't have agency at all.
  • tendency to explain the natural world through the existence of beings with supernatural powers — things like gods, ancestral spirits, goblins and fairies — formed the basis for religious beliefs, according to many cognitive scientists.
  • They started attributing meaning to the actions of things that weren't really acting of their own accord.
  • they started anticipating what other beings' actions might be and planning their own actions accordingly.
  • "You might think that raindrops aren't agents," Clark said. "They can't act of their own accord. They just fall.
  • enabled them to discern other people's positive and negative intentions
  • thereby increasing their own chances of survival.
  • attributing purpose to the actions of nonactors, like raindrops, ToM took a turn toward the supernatural.
  • Theory of Mind
  • refer to HADD and ToM as the "god faculty,"
  • human beings haven't evolved past this way of thinking and making decisions,
    • paisleyd
       
      We are still in the same evolutionary mind set of daily survival so it makes sense that attributing emotion and reasoning onto things around us has not changed either.
  • "You can be educated out of some of these beliefs, but you can't be educated out of these cognitive faculties. We all have a hyperactive agency-detecting device. We all have a theory of mind."
  • a trait that stuck around because the people who possessed it were better able to survive and pass on their genes.
  • Religion may have naturally sprung up from this need to keep everybody on the same page,
  • Humans' predisposition to attribute intention to just about everything (e.g., volcanic eruptions, lunar eclipses, thunderstorms) isn't necessarily the reason religion came about,
cvanderloo

Sewage-testing robots process wastewater faster to predict COVID-19 outbreaks sooner - 0 views

  • By using a sewage-handling robot, our laboratory has been able to detect coronavirus in wastewater 30 times faster than nonautomated large-scale systems.
  • When clinical studies emerged showing that people who test positive for SARS-CoV-2 shed the virus in their stool, the sewer seemed like an obvious place to look for it.
  • Surveillance depends on concentrating the viral particles from the wastewater to detect these low levels.
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  • Wastewater surveillance is especially useful as an early-alert system for high-risk areas, such as communities where undocumented residents may be cautious about individual testing.
  • Our new protocol concentrates 24 samples in a single 40-minute run.
  • The sewage-handling robot is equipped with a specialized magnetic head that snags the magnetic beads, with viruses attached.
  • Overall, our system can process 96 samples in 4.5 hours, dramatically reducing the time from specimen to result.
  • We’re now using the viral genome sequencing part of our system to track the emergence of new SARS-CoV-2 variants.
aprossi

US Coronavirus: Now that new Covid-19 variants are circulating everyday activities are ... - 0 views

  • Everyday activities are more dangerous now that new Covid-19 variants are circulating
  • (CNN)Health officials are "extremely" worried about the new Covid-19 variants that have been detected in the US and what they could mean over the coming months, one expert said Monday night.
  • CDC officials have also said another variant -- called B.1.1.7 and first spotted in the UK -- has been detected in more than 20 states.
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  • with 42 states reporting downward trends
  • Moderna says its vaccine protects against some variants
  • The good news, Fauci told CNN in a separate interview Monday, is that current Covid-19 vaccines are likely to be effective against the new variants.
  • Moderna said Monday its vaccine created antibodies that neutralized Covid-19 variants first found in the UK and South Africa
  • So far, about 19 million people -- nearly 6% of the US population -- have received at least the first dose of the Covid-19 vaccine, according to CDC data. More than 3.3 million are fully vaccinated.
  • 100 million shots administered in the President's first 100 days in office.
  • Kentucky has used about 88% of their first doses
anonymous

Can you trust your earliest childhood memories? - BBC Future - 1 views

  • The moments we remember from the first years of our lives are often our most treasured because we have carried them longest. The chances are, they are also completely made up.
  • Around four out of every 10 of us have fabricated our first memory, according to researchers. This is thought to be because our brains do not develop the ability to store autobiographical memories at least until we reach two years old.
  • Yet a surprising number of us have some flicker of memory from before that age
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  • Experts have managed to turn people off all sorts of foods by convincing them it had made them ill when they were a child
  • “People have a life story, particularly as they get older and for some people it needs to stretch back to the very early stage of life,”
  • The prevailing account of how we come to believe and remember things is based around the concept of source monitoring. “Every time a thought comes to mind we have to make a decision – have we experienced it [an event], imagined it or have we talked about it with other people,” says Kimberley Wade
  • Most of the time we make that decision correctly and can identify where these mental experiences come from, but sometimes we get it wrong.
  • Wade admits she has spent a lot of time recalling an event that was actually something her brother experienced rather than herself, but despite this, it is rich in detail and provokes emotion
  • Memory researchers have shown it is possible to induce fictional autobiographical memories in volunteers, including accounts of getting lost in a shopping mall and even having tea with a member of the Royal Family
  • Based on my research, everybody is capable of forming complex false memories, given the right circumstances – Julia Shaw
  • In some situations, such as after looking at pictures or a video, children are more susceptible to forming false memories than adults. People with certain personality types are also thought to be more prone.
  • But carrying around false memories from your childhood could be having a far greater impact on you than you may realise too. The events, emotions and experiences we remember from our early years can help to shape who we are as adults, determining our likes, dislikes, fears and even our behaviour.
  • Memories before the age of three are more than likely to be false. Any that appear very fluid and detailed, as if you were playing back a home video and experiencing a chronological account of a memory, could well also be made up. It is more likely that fuzzy fragments, or snapshots of moments are real, as long as they are not from too early in your life.
  • We crave a cohesive narrative of our own existence and will even invent stories to give us a more complete picture
  • Interestingly, scientists have also found positive suggestions, such as “you loved asparagus the first time you ate it” tend to be more effective than negative suggestions like “you got sick drinking vodka”
  • “Miscarriage of justice, incarceration, loss of reputation, job and status, and family breakdown occur,
  • One of the major problems with legal cases involving false memories, is that it is currently impossible to distinguish between true and fictional recollections
  • Efforts have been made to analyse minor false memories in a brain scanner (fMRI) and detect different neurological patterns, but there is nothing as yet to indicate that this technology can be used to detect whether recollections have become distorted.
  • the most extreme case of memory implantation involves a controversial technique called “regression therapy”, where patients confront childhood traumas, supposedly buried in their subconscious
  • “Memories are malleable and tend to change slightly each time we revisit them, in the same way that spoken stories do,”
  • “Therefore at each recollection, new elements can easily be integrated while existing elements can be altered or lost.”
  • This is not to say that all evidence that relies on memory should be discarded or regarded as unreliable – they often provide the most compelling testimony in criminal cases. But it has led to rules and guidelines about how witnesses and victims should be questioned to ensure their recollections of an event or perpetrator are not contaminated by investigators or prosecutors.
  • Any memories that appear very fluid and detailed, as if you were playing back a home video, could well also be made up
  • While this may seem like a bit of fun, many scientists believe the “false memory diet” could be used to tackle obesity and encourage people to reach for healthier options like asparagus, or even help cut people’s alcohol consumption.
  • Children are more susceptible to forming false memories than adults, especially after looking at photographs or films
  • And we may not want to rid ourselves of these memories. Our memories, whether fictional or not, can help to bring us closer together.
  •  
    This is a great and very detailed article about memory and how we change our own memories and are impacted by this change.
knudsenlu

Will the Quantum Nature of Gravity Finally Be Measured? - The Atlantic - 0 views

  • In 1935, when both quantum mechanics and Albert Einstein’s general theory of relativity were young, a little-known Soviet physicist named Matvei Bronstein, just 28 himself, made the first detailed study of the problem of reconciling the two in a quantum theory of gravity. This “possible theory of the world as a whole,” as Bronstein called it, would supplant Einstein’s classical description of gravity, which casts it as curves in the space-time continuum, and rewrite it in the same quantum language as the rest of physics.
  • His words were prophetic. Eighty-three years later, physicists are still trying to understand how space-time curvature emerges on macroscopic scales from a more fundamental, presumably quantum picture of gravity; it’s arguably the deepest question in physics.
  • The search for the full theory of quantum gravity has been stymied by the fact that gravity’s quantum properties never seem to manifest in actual experience. Physicists never get to see how Einstein’s description of the smooth space-time continuum, or Bronstein’s quantum approximation of it when it’s weakly curved, goes wrong.
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  • Not only that, but the universe appears to be governed by a kind of cosmic censorship: Regions of extreme gravity—where space-time curves so sharply that Einstein’s equations malfunction and the true, quantum nature of gravity and space-time must be revealed—always hide behind the horizons of black holes.
  • Dyson, who helped develop quantum electrodynamics (the theory of interactions between matter and light) and is professor emeritus at the Institute for Advanced Study in Princeton, New Jersey, where he overlapped with Einstein, disagrees with the argument that quantum gravity is needed to describe the unreachable interiors of black holes. And he wonders whether detecting the hypothetical graviton might be impossible, even in principle. In that case, he argues, quantum gravity is metaphysical, rather than physics.
  • The ability to detect the “grin” of quantum gravity would seem to refute Dyson’s argument. It would also kill the gravitational decoherence theory, by showing that gravity and space-time do maintain quantum superpositions.
  • If gravity is a quantum interaction, then the answer is: It depends. Each component of the blue diamond’s superposition will experience a stronger or weaker gravitational attraction to the red diamond, depending on whether the latter is in the branch of its superposition that’s closer or farther away. And the gravity felt by each component of the red diamond’s superposition similarly depends on where the blue diamond is.
manhefnawi

Are Smart People More Likely to Believe Stereotypes? | Mental Floss - 0 views

  • There are many different kinds of intelligence, each reliant on its own set of skills and abilities. One such ability is pattern recognition, without which we’d have trouble recognizing faces, learning languages, or reading other people’s emotions. Because it’s so central to our cognitive and social functioning, pattern recognition is sometimes used by researchers as a shorthand for overall intelligence.
  • Finding that higher pattern detection ability puts people at greater risk to detect and apply stereotypes, but also to reverse them, implicates this ability as a cognitive mechanism underlying stereotyping,” co-author Jonathan Freeman said in the statement.
katherineharron

How to be a human lie detector of fake news - CNN - 0 views

  • Fake news existed long before the internet. In an essay on political lying in the early 18th century, the writer Jonathan Swift noted that "Falsehood flies and the truth comes limping after it." You have to hire a train to pull the truth, explained English pastor Charles Spurgeon in the 19th century, while a lie is "light as a feather ... a breath will carry it."
  • MIT researchers recently studied more than 10 years' worth of data on the most shared stories on Facebook. Their study covered conspiracy theories about the Boston bombings, misleading reports on natural disasters, unfounded business rumors and incorrect scientific claims. There is an inundation of false medical advice online, for example, that encourages people to avoid life-saving treatments such as vaccines and promotes unproven therapies. (Gwyneth Paltrow's Goop is just one example.)
  • The psychological research does, however, offer us a silver lining to this storm cloud, with various experiments demonstrating that people can learn to be better lie detectors with a little training in critical thinking.
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  • If you would like to improve your own lie detection, a good first step is to learn the common logical fallacies -- red herrings, appeals to ignorance, straw men and "ad populum" appeals to the bandwagon -- that purveyors of misinformation may use to create the illusion of truth.
  • These efforts are often called "inoculations," since they use a real-life example in one domain to teach people about the strategies used to spread lies and therefore equipping people to spot them more easily. Educating people about the tobacco industry's attempts to question the medical consensus on smoking, for example, led people to be more skeptical of articles denying climate change, according to one study.
  • Another project aimed to inoculate students at North Carolina State University in Raleigh, involved a course on misinformation throughout history. The class was taught about everything from the myth that aliens somehow built the Egyptian pyramids to the theories that NASA's moon landings were faked. Along the way, the students had to identify the erroneous logic that helped create the arguments, and the motivations that may lead some people to spread those ideas.
  • You could also try basic strategies such as cross-checking different outlets and finding the original source of a claim. You might also look at independent fact-checking websites used in the MIT study such as Snopes, PolitiFact and TruthOrFiction.com.
  • The psychological literature offers us one good strategy against bias, called the "consider the opposite" method. This involves asking yourself whether you would have been so credulous of a claim if its opinions had differed from your own. And if not, what kind of additional scrutiny might you have applied? This should help you to identify the weaknesses in your own thinking.
  • Falsehoods may fly, but with this lie detection kit, you can better ensure your actions and beliefs remain grounded in the truth.
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