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Emily Freilich

Rights group's report offers compelling evidence of Syria chemical attack - CBS News - 0 views

  • On Tuesday, the group Human Rights Watch issued a report that said evidence strongly implies that Syrian government troops' firing of rockets containing a nerve agent into a Damascus suburb on August 21 that the U.S. said killed over 1,400 people.
  • While the report doesn't furnish conclusive proof that the Syrian government carried out the attack with chemical weapons, it does present the most coherent circumstantial evidence I've seen so far to support the case.
  • The report does not rely on ambiguous intercepted phone calls. It cites no shadowy intelligence gathering
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  • HRW's experts take a close look at witness statements and photographs and video of the victims and -- above all -- the remains of the weapons that appear to have been used.
  • The report provides another map that shows that there were several military bases around Zamalka and Moadimiyeh on August 21st, that were within the correct firing distanc
lucieperloff

When It Comes to Octopuses, Taste Is for Suckers - The New York Times - 0 views

  • The cells of octopus suckers are decorated with a mixture of tiny detector proteins. Each type of sensor responds to a distinct chemical cue, giving the animals an extraordinarily refined palate that can inform how their agile arms react, jettisoning an object as useless or dangerous, or nabbing it for a snack.
  • Though humans have nothing quite comparable in their anatomy, being an octopus might be roughly akin to exploring the world with eight giant, sucker-studded tongues
  • The internal architecture of an octopus is as labyrinthine as it is bizarre. Nestled inside each body are three hearts, a parrot-like beak and, arguably, nine “brains”
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  • Imbued with their own neurons, octopus arms can act semi-autonomously, gathering and exchanging information without routing it through the main brain.
  • It’s long been unclear, for instance, how the animals, just by probing their surroundings with their limbs, can distinguish something like a crab from a less edible object.
  • exposed to octopus ink, which is sometimes released as a “warning signal,” Dr. van Giesen said. “Maybe there is some kind of filtering of information that is important for the animal in specific situations,” like when danger is afoot, she said.
  • But they found that some of the cells in the animal’s suckers would shut down when
  • Humans, who tend to be very visual creatures, probably can’t fully appreciate the sensory nuances of a taste-sensitive arm
  • “Sometimes we assume in neuroscience or animal behavior, there’s only one way of doing it
  • But then again, most people could probably do without the metallic tang of keys every time they rummage in their pockets — or the funk that would inevitably dissuade every new parent from changing a diaper.
  • (Even after amputation, these adept appendages can still snatch hungrily at morsels of food.)
    • lucieperloff
       
      Octopus tentacles have many abilities - not just movement
  • The cells of octopus suckers are decorated with a mixture of tiny detector proteins. Each type of sensor responds to a distinct chemical cue, giving the animals an extraordinarily refined palate that can inform how their agile arms react, jettisoning an object as useless or dangerous, or nabbing it for a snack.
    • lucieperloff
       
      Octopuses can know what they are touching and know if they can consume it
  • That arm has all the cellular machinery to taste your tongue right back.
  • Each type of sensor responds to a distinct chemical cue, giving the animals an extraordinarily refined palate that can inform how their agile arms react, jettisoning an object as useless or dangerous, or nabbing it for a snack.
  • Octopuses certainly know how to put that processing power to good use.
    • lucieperloff
       
      Octopuses are smart and can behave intentionally
  • By mixing and matching these proteins, cells could develop their own unique tasting profiles, allowing the octopus’s suckers to discern flavors in fine gradations, then shoot the sensation to other parts of the nervous system.
  • Underwater, some chemicals can travel far from their source, making it possible for some creatures to catch a whiff of their prey from afar. But for chemicals that don’t move through the ocean easily, a touch-taste strategy is handy, Dr. Bellono said.
    • lucieperloff
       
      Being able to taste with their tentacles has many real-life benefits for octopi
anonymous

How social isolation transforms the brain: A particular neural chemical is overproduced... - 0 views

  • Chronic social isolation has debilitating effects on mental health in mammals -- for example, it is often associated with depression and post-traumatic stress disorder in humans. Now, a team of Caltech researchers has discovered that social isolation causes the build-up of a particular chemical in the brain, and that blocking this chemical eliminates the negative effects of isolation. The work has potential applications for treating mental health disorders in humans.
  • For example, when encountering a threatening stimulus, mice that have been socially isolated remain frozen in place long after the threat has passed, whereas normal mice stop freezing soon after the threat is removed. These effects are seen when mice are subjected to two weeks of social isolation, but not to short-term social isolation -- 24 hours -- suggesting that the observed changes in aggression and fear responses require chronic isolation.
  • The researchers found that chronic isolation leads to an increase in Tac2 gene expression and the production of NkB throughout the brain. However, administration of a drug that chemically blocks NkB-specific receptors enabled the stressed mice to behave normally, eliminating the negative effects of social isolation. Conversely, artificially increasing Tac2 levels and activating the corresponding neurons in normal, unstressed animals led them to behave like the stressed, isolated animals.
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  • The results imply that Tac2 must increase in different brain regions to produce the various effects of social isolation.
  • Though the work was done in mice, it has potential implications for understanding how chronic stress affects humans.
  • Manipulating these systems broadly can lead to unwanted side effects. So, being able to precisely and locally modify a neuropeptide like Tac2 is a promising approach to mental health treatments.
runlai_jiang

Reactivity Definition in Chemistry - 0 views

  • In chemistry, reactivity is a measure of how readily a substance undergoes a chemical reaction. The reaction can involve the substance on its own or with other atoms or compounds, generally accompanied by a release of energy. The most reactive elements and compounds may ignite spontaneously or explosively. They generally burn in water as well as the oxygen in air. Reactivity is dependent upon temperature.
  • Reactivity Trend in the Periodic TableThe organization of elements on the periodic table allows for predictions concerning reactivity. Both highly electropositive and highly electronegative elements have a strong tendency to react. These elements are located in the upper right and lower left corners of the periodic table and in certain element groups. The halogens, alkali metals, and alkaline earth metals are highly reactive.
  • How Reactivity WorksA substance reacts when the products formed from a chemical reaction have a lower energy (higher stability) than the reactants. The energy difference can be predicted using valence bond theory, atomic orbital theory, and molecular orbital theory. Basically, it boils down to the stability of electrons in their orbitals. Unpaired electrons with no electrons in comparable orbitals are the most likely to interact with orbitals from other atoms, forming chemical bonds. Unpaired electrons with degenerate orbitals that are half-filled are more stable, but still reactive. The least reactive atoms are those with a filled set of orbitals (octet).
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  • Stability Versus ReactivitySometimes a species with low reactivity is called "stable", but care should be taken to make the context clear. Stability can also refer to slow radioactive decay or to the transition of electrons from the excited state to less energetic levels (as in luminescence). A nonreactive species may be called "inert". However, most inert species actually do react under the right conditions to form complexes and compounds (e.g., higher atomic number noble gases).
kortanekev

How Animals Communicate Via Pheromones » American Scientist - 0 views

  • Pheromones are chemical signals that have evolved for communication between members of the same species. A pheromone signal elicits a specific reaction in the receiver, for example, a stereotyped behavior
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    This article depicts an efficient and accurate form of communication that is not dynamic or abstract in any way like the languages we use. This form is pheromones which are chemicals that animals have evolved to secrete, receive, and respond to instinctively. Despite being a process that we can't control, it does serve as an effective communication that does not depend on our subjective deciphering.  (Evie 11/27/16)
Maria Delzi

How Life Began: New Clues | TIME.com - 0 views

  • Astronomers recently announced that there could be an astonishing 20 billion Earthlike planets in the Milky Way
  • How abundant life actually is, however, hinges on one crucial factor: given the right conditions and the right raw materials,
  • what is the mathematical likelihood that life will actually would arise?
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  • biology would have to be popping up all over the place.
  • Andrew Ellington, of the Center for Systems and Synthetic Biology at the University of Texas, Austin, “I can’t tell you what the probability is. It’s a chapter of the story that’s pretty much blank.”
  • Given that rather bleak-sounding assessment, it may be surprising to learn that Ellington is actually pretty upbeat. But that’s how he and two colleagues come across in a paper in the latest Science. The crucial step from nonliving stuff to a live cell is still a mystery, they acknowledge, but the number of pathways a mix of inanimate chemicals could have taken to reach the threshold of the living turns out to be many and varied. “It’s difficult to say exactly how things did occur,” says Ellington. “But there are many ways it could have occurred.
  • The first stab at answering the question came all the way back in the 1950s, when chemists Stanley Miller and Harold Urey passed an electrical spark through a beaker containing methane, ammonia, water vapor and hydrogen, thought at the time to represent Earth’s primordial atmosphere.
  • Scientists have learned so much, in fact, that the number of places life might have begun has grown to include such disparate locations as the hydrothermal vents at the bottom of the ocean; beds of clay; the billowing clouds of gas emerging from volcanoes; and the spaces in between ice crystals.
  • The number of ideas about how the key step from organic chemicals to living organisms might have been taken has multiplied as well: there’s the “RNA world hypothesis” and the “lipid world hypothesis” and the “iron-sulfur world hypothesis” and more, all of them dependent on a particular set of chemical circumstances and a particular set of dynamics and all highly speculative.
  • “Maybe when they do,” says Ellington, “we’ll all do a face-plant because it turns out to be so obvious in retrospect.” But even if they succeed, it will only prove that a manufactured cell could represent the earliest life forms, not that it actually does. “It will be a story about what we think might have happened, but it will still be a story.”
  • The story Ellington and his colleagues have been able to tell already, however, is a reason for optimism. We still don’t know the odds that life will arise under the right conditions. But the underlying biochemistry is abundantly, ubiquitously available—and it would take an awfully perverse universe to take things so far only to shut them down at the last moment.
julia rhodes

The Primate Brain Likes to Win, But Can't Always Have It | Psychology Today - 0 views

  • Winning stimulates dopamine, serotonin and oxytocin. Just watching competition stimulates these happy chemicals through our mirror neurons.
  • Happy chemicals are stimulated by behaviors that promote survival in the state of nature.
  •  Dopamine is the good feeling of getting a reward the meets your needs.
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  • Once he gets the fruit, his dopamine stops. The good feeling will be gone as soon as it's metabolized. To get more, he will have to do more.  Natural selection produced a brain that feels good when it works toward a goal.
  • The monkey's brain weighs the evidence based on past experience. The fruit he scored in the past triggered dopamine that paved neural pathways and trigger his dopamine today. But the pain of past setbacks built cortisol pathways that alert him to the risk of setbacks today.
  • Your brain evolved to stimulate them by takig action to meet your needs. Just taking steps toward skill building gets your happy chemicals flowing once you've built the circuits that kick-start the process.
  • different kind of motivation comes from serotonin. Let's say our monkey's fruit is snatched by a bigger, stronger monkey when he finally gets to the top of the tree. Experience has taught him that bigger monkeys cause pain, and falling from a tree causes pain.
  • A surge of serotonin causes this feeling. Experience teaches a monkey to determine when he is in the superior position and when he is in the inferior position.
  • These words horrify us in today's culture, but a monkey would starve to death if it always saw itself as inferior. It has to feel confident to go for it some of the time. Serotonin creates that confidence.
  • You may say that monkeys should cooperate, share the bananas, or leave the bananas for the needy. By saying these things, you mark yourself as a superior person in today's society. You are just seeking serotonin in the modern way. You stimulate oxytocin when your self-restraint helps you belong
  •  Oxytocin causes the good feeling of social solidarity, and low oxytocin warns your inner mammal that you're in immediate danger. Our brains are constantly aware of potential threats to our social bonds. Competition can threaten your bonds, but it can also strengthen them. Superior skills can bring recognition that reassures you of social acceptance and belonging. Secure social bonds feel good because they stimulate oxytocin.
  • Your inner mammal is always looking for ways to stimulate your dopamine, serotonin and oxytocin.
  • Your mirror neurons stimulate dopamine when you see other people get rewards
Javier E

Big Think Interview With Nicholas Carr | Nicholas Carr | Big Think - 0 views

  • Neurologically, how does our brain adapt itself to new technologies? Nicholas Carr: A couple of types of adaptations take place in your brain. One is a strengthening of the synaptical connections between the neurons involved in using that instrument, in using that tool. And basically these are chemical – neural chemical changes. So you know, cells in our brain communicate by transmitting electrical signals between them and those electrical signals are actually activated by the exchange of chemicals, neurotransmitters in our synapses. And so when you begin to use a tool, for instance, you have much stronger electrochemical signals being processed in those – through those synaptical connections. And then the second, and even more interesting adaptation is in actual physical changes,anatomical changes. Your neurons, you may grow new neurons that are then recruited into these circuits or your existing neurons may grow new synaptical terminals. And again, that also serves to strengthen the activity in those, in those particular pathways that are being used – new pathways. On the other hand, you know, the brain likes to be efficient and so even as its strengthening the pathways you’re exercising, it’s pulling – it’s weakening the connections in other ways between the cells that supported old ways of thinking or working or behaving, or whatever that you’re not exercising so much.
  • And it was only in around the year 800 or 900 that we saw the introduction of word spaces. And suddenly reading became, in a sense, easier and suddenly you had to arrival of silent reading, which changed the act of reading from just transcription of speech to something that every individual did on their own. And suddenly you had this whole deal of the silent solitary reader who was improving their mind, expanding their horizons, and so forth. And when Guttenberg invented the printing press around 1450, what that served to do was take this new very attentive, very deep form of reading, which had been limited to just, you know, monasteries and universities, and by making books much cheaper and much more available, spread that way of reading out to a much larger mass of audience. And so we saw, for the last 500 years or so, one of the central facts of culture was deep solitary reading.
  • What the book does as a technology is shield us from distraction. The only thinggoing on is the, you know, the progression of words and sentences across page after page and so suddenly we see this immersive kind of very attentive thinking, whether you are paying attention to a story or to an argument, or whatever. And what we know about the brain is the brain adapts to these types of tools.
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  • we adapt to the environment of the internet, which is an environment of kind of constant immersion and information and constant distractions, interruptions, juggling lots of messages, lots of bits of information.
  • Because it’s no longer just a matter of personal choice, of personal discipline, though obviously those things are always important, but what we’re seeing and we see this over and over again in the history of technology, is that the technology – the technology of the web, the technology of digital media, gets entwined very, very deeply into social processes, into expectations. So more and more, for instance in our work lives. You know, if our boss and all our colleagues are constantly exchanging messages, constantly checking email on their Blackberry or iPhone or their Droid or whatever, then it becomes very difficult to say, I’m not going to be as connected because you feel like you’re career is going to take a hit.
  • With the arrival – with the transfer now of text more and more onto screens, we see, I think, a new and in some ways more primitive way of reading. In order to take in information off a screen, when you are also being bombarded with all sort of other information and when there links in the text where you have to think even for just a fraction of a second, you know, do I click on this link or not. Suddenly reading again becomes a more cognitively intensive act, the way it was back when there were no spaces between words.
  • If all your friends are planning their social lives through texts and Facebook and Twitter and so forth, then to back away from that means to feel socially isolated. And of course for all people, particularly for young people, there’s kind of nothing worse than feeling socially isolated, that your friends are you know, having these conversations and you’re not involved. So it’s easy to say the solution, which is to, you know, becomes a little bit more disconnected. What’s hard it actually doing that.
  • if you want to change your brain, you change your habits. You change your habits of thinking. And that means, you know, setting aside time to engage in more contemplative, more reflective ways of thinking and that means, you know, setting aside time to engage in more contemplative, more reflective ways of thinking, to be – to screen out distractions. And that means retreating from digital media and from the web and from Smart Phones and texting and Facebook and Tweeting and everything else.
  • The Thinker was, you know, in a contemplative pose and was concentrating deeply, and wasn’t you know, multi-tasking. And because that is something that, until recently anyway, people always thought was the deepest and most distinctly human way of thinking.
  • we may end up finding that those are actually the most valuable ways of thinking that are available to us as human beings.
  • the ability to pay attention also is very important for our ability to build memories, to transfer information from our short-term memory to our long-term memory. And only when we do that do we weave new information into everything else we have stored in our brains. All the other facts we’ve learned, all the other experiences we’ve had, emotions we’ve felt. And that’s how you build, I think, a rich intellect and a rich intellectual life.
  • On the other hand, there is a cost. We lose – we begin to lose the facilities that we don’t exercise. So adaptation has both a very, very positive side, but also a potentially negative side because ultimately our brain is qualitatively neutral. It doesn’t pare what it’s strengthening or what it’s weakening, it just responds to the way we’re exercising our mind.
  • the book in some ways is the most interesting from our own present standpoint, particularly when we want to think about the way the internet is changing us. It’s interesting to think about how the book changed us.
  • So we become, after the arrival of the printing press in general, more attentive more attuned to contemplative ways of thinking. And that’s a very unnatural way of using our mind. You know, paying attention, filtering out distractions.
  • what we lose is the ability to pay deep attention to one thing for a sustained period of time, to filter out distractions.
Javier E

Pesticides Linked to Honeybee Deaths Pose More Risks, European Group Says - NYTimes.com - 0 views

  • An influential European scientific body said on Wednesday that a group of pesticides believed to contribute to mass deaths of honeybees is probably more damaging to ecosystems than previously thought and questioned whether the substances had a place in sustainable agriculture.
  • A growing body of evidence shows that the widespread use of the pesticides “has severe effects on a range of organisms that provide ecosystem services like pollination and natural pest control, as well as on biodiversity,” the report’s authors said.
  • Predatory insects like parasitic wasps and ladybugs provide billions of dollars’ worth of insect control, they noted, and organisms like earthworms contribute billions more through improved soil productivity. All are harmed by the pesticides.
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  • The authors were critical of studies of neonicotinoids on bee health that tested the insects’ ability to survive a single exposure to a given quantity of pesticide dust; they noted that the effect of the chemicals is cumulative and irreversible, meaning that repeated sublethal doses will eventually be deadly if a certain threshold is passed.
  • The restrictive approach used by European regulators contrasts with the more lenient stance of United States regulators. In March, American opponents of neonicotinoid use delivered more than four million signatures to the White House calling for stronger action to protect pollinators.
  • critics say the E.P.A.’s interim policy is rife with loopholes, allowing continued use of existing products for approved applications, for example. They also criticized the agency for not halting the approval of some products that are chemically quite similar to neonicotinoids but classified differently for regulatory purposes.
  • Pollination — the transfer of pollen from one flower to another, typically by wind, bug or bird — is essential to the global food supply. An estimated 75 percent of all traded crops, including apples, soybeans and corn, depend on pollination.
  • Neonicotinoids are absorbed by a plant so that the neurotoxic poison spreads throughout its tissues, including the sap, nectar and pollen. Far more deadly to insects than to mammals, they do not discriminate between harmful pests and beneficial pollinators.
haubertbr

How Syria and Russia Spun a Chemical Strike - 0 views

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    A New York Times investigation shows how Syria and its main partner, Russia, have distorted the facts surrounding the chemical weapons attack on Khan Sheikhoun.
Javier E

How thinking hard makes the brain tired | The Economist - 0 views

  • Mental labour can also be exhausting. Even resisting that last glistening chocolate-chip cookie after a long day at a consuming desk job is difficult. Cognitive control, the umbrella term encompassing mental exertion, self-control and willpower, also fades with effort.
  • unlike the mechanism of physical fatigue, the cause of cognitive fatigue has been poorly understood.
  • It posits that exerting cognitive control uses up energy in the form of glucose. At the end of a day spent intensely cogitating, the brain is metaphorically running on fumes. The problem with this version of events is that the energy cost associated with thinking is minimal.
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  • To induce cognitive fatigue, a group of participants were asked to perform just over six hours of various tasks that involve thinking.
  • In other words, cognitive work results in chemical changes in the brain, which present behaviourally as fatigue. This, therefore, is a signal to stop working in order to restore balance to the brain.
  • a neurometabolic point of view. They hypothesise that cognitive fatigue results from an accumulation of a certain chemical in the region of the brain underpinning control. That substance, glutamate, is an excitatory neurotransmitter
  • Periodically, throughout the experiment, participants were asked to make decisions that could reveal their cognitive fatigue.
  • The time it takes for the pupil to subsequently dilate reflects the amount of mental exerted. The pupil-dilation times of participants assigned hard tasks fell off significantly as the experiment progressed.
  • During the experiment the scientists used a technique called magnetic-resonance spectroscopy to measure biochemical changes in the brain. In particular, they focused on the lateral prefrontal cortex, a region of the brain associated with cognitive control. If their hypothesis was to hold, there would be a measurable chemical difference between the brains of hard- and easy-task participants
  • Their analysis indicated higher concentrations of glutamate in the synapses of a hard-task participant’s lateral prefrontal cortex. Thus showing cognitive fatigue is associated with increased glutamate in the prefrontal cortex
  • There may well be ways to reduce the glutamate levels, and no doubt some researchers will now be looking at potions that might hack the brain in a way to artificially speed up its recovery from fatigue. Meanwhile, the best solution is the natural one: sleep
Dunia Tonob

Our lives are not our own. - 1 views

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    The chemicals in our brain that produce emotions.
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."
  • 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.
  • 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.
  • 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.
  • "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.
Emily Horwitz

New Genetic Twist: 4-Stranded DNA Lurks in Human Cells | LiveScience - 1 views

  • Sixty years after scientists described the chemical code of life — an interweaving double helix called DNA — researchers have found four-stranded DNA is also lurking in human cells.
  • they form in regions of deoxyribonucleic acid (DNA) that are full of guanine, one of the DNA molecule's four building blocks
  • Scientists had shown in the past that such quadruplex DNA could form in test tubes and had even been found in the cells of ciliated protozoa, or single-celled organisms with hairlike appendages. Also there were hints of its existence in human cells, though no direct proof, Lipps said.
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  • In the new study, researchers, including chemist Shankar Balasubramanian, of the University of Cambridge and Cambridge Research Institute, crafted antibody proteins specifically for this type of DNA. The proteins were marked with a fluorescent chemical, so when they hooked up to areas in the human genome packed with G-quadruplexes, they lit up.
  • Next, they incubated the antibodies with human cells in the lab, finding these structures tended to occur in genes of cells that were rapidly dividing, a telltale feature of cancer cells. They also found a spike in quadruplexes during the s-phase of the cell cycle, or the phase when DNA replicates just before the cell divides.
  • the researchers think the four-stranded DNA could be a target for personalized medicine in the future
  • "What makes me personally very happy about this work is that it again demonstrates that mechanisms first described in ciliated protozoa hold also true for other organisms up to human, demonstrating the strength of this model organism," wrote Lipps wrote.
sissij

Depression is as bad for your heart as high cholesterol | Fox News - 0 views

  • When you think of heart attacks, you might assume the most common causes are smoking, high cholesterol, or obesity. Mental health issues probably don't spring to mind.
  • Depression—which for this study, was determined by a checklist of mood symptoms, including anxiety and fatigue
  • “depressed mood and exhaustion holds a solid middle position within the concert of major cardiovascular risk factors.”
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    I think it is really interesting that even mental health issues has a positive relationship with cardiovascular disease. Our mind can affect how our body works. As we learn in the sense and perception unit, we know that brain will give us a shot of certain chemical that makes us feel good when we make certain decision. I think how we feel can reflect how our body feels. We all know that we feel pain because it is a warning that the injured part of our body send to our brain. So I think probably the feeling of depressed can be a warning sent by some part of our body. The scientific method mentioned in this article is a population research which is a typical biology scientific method. --Sissi (1/29/2017)
Adam Clark

Does Your Language Shape How You Think? - NYTimes.com - 0 views

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    "Seventy years ago, in 1940, a popular science magazine published a short article that set in motion one of the trendiest intellectual fads of the 20th century. At first glance, there seemed little about the article to augur its subsequent celebrity. Neither the title, "Science and Linguistics," nor the magazine, M.I.T.'s Technology Review, was most people's idea of glamour. And the author, a chemical engineer who worked for an insurance company and moonlighted as an anthropology lecturer at Yale University, was an unlikely candidate for international superstardom. And yet Benjamin Lee Whorf let loose an alluring idea about language's power over the mind, and his stirring prose seduced a whole generation into believing that our mother tongue restricts what we are able to think."
grayton downing

In Syria, Doctors Risk Life and Juggle Ethics - NYTimes.com - 1 views

  • Majid, who gave only his first name to protect his safety, collected hair and urine samples, clothing, tree leaves, soil and even a dead bird. He shared it with the Syrian American Medical Society, a humanitarian group that had been delivering such samples to American intelligence officials, as proof of possible chemical attacks.
  • United Nations inspectors have taken the first steps to destroy Syria’s chemical stockpile.
  • Many Syrian doctors have fled; those who remain describe dire conditions where even the most basic care is not available.
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  • Mothers are desperate to have their children vaccinated; patients with chronic conditions like heart disease and diabetes struggle to get medicine; and there is “huge anxiety in the population,”
  • On Aug. 21, the group got word from some of its “silent partner” hospitals of a flood of patients with “neurotoxic symptoms” — roughly 3,600 in a period of three hours, including 355 who died.
  • The debate over whether doctors should expose human rights abuses has long been “one of these inside baseball arguments within the humanitarian community,” said Len Rubenstein, an expert on human rights and medical ethics at Johns Hopkins University. While Doctors Without Borders has a culture of “bearing witness,” he said, not all humanitarian organizations do.
  • The International Committee of the Red Cross, for instance, adheres to a strict code of political neutrality;
grayton downing

In Syria, Doctors Risk Life and Juggle Ethics - NYTimes.com - 1 views

  • “Doctors are notoriously poor evaluators of chemical warfare injuries if they have never seen them before,”
  • Those reports, he said, were later “cynically manipulated” by American intelligence officials to assert that Iran — not Iraq — was using cyanide. In fact, he continued, there is no evidence that either side was.
  • It’s not our role to collect samples for any government or investigative agency.
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  • In an interview afterward, he said he was able to take samples from two people; the crush of patients was too overwhelming to do more. He worried about preserving them; with electricity working only sporadically, there was no constant refrigeration.
  • “with some degree of varying confidence,” Mr. Hagel said — that the Syrian government had used chemical weapons.
kushnerha

A Placebo Treatment for Pain - The New York Times - 0 views

  • This phenomenon — in which someone feels better after receiving fake treatment — was once dismissed as an illusion. People who are ill often improve regardless of the treatment they receive. But neuroscientists are discovering that in some conditions, including pain, placebos create biological effects similar to those caused by drugs.
  • a key ingredient is expectation: The greater our belief that a treatment will work, the better we’ll respond.
  • Placebo effects in pain are so large, in fact, that drug manufacturers are finding it hard to beat them. Finding ways to minimize placebo effects in trials, for example by screening out those who are most susceptible, is now a big focus for research. But what if instead we seek to harness these effects? Placebos might ruin drug trials, but they also show us a new approach to treating pain.
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  • It is unethical to deceive patients by prescribing fake treatments, of course. But there is evidence that people with some conditions benefit even if they know they are taking placebos. In a 2014 study that followed 459 migraine attacks in 66 patients, honestly labeled placebos provided significantly more pain relief than no treatment, and were nearly half as effective as the painkiller Maxalt.
  • With placebo responses in pain so high — and the risks of drugs so severe — why not prescribe a course of “honest” placebos for those who wish to try it, before proceeding, if necessary, to an active drug?
  • Another option is to employ alternative therapies, which through placebo responses can benefit patients even when there is no physical mode of action.
  • Taking a placebo painkiller dampens activity in pain-related areas of the brain and spinal cord, and triggers the release of endorphins, the natural pain-relieving chemicals that opioid drugs are designed to mimic. Even when we take a real painkiller, a big chunk of its effect is delivered not by any direct chemical action, but by our expectation that the drug will work. Studies show that widely used painkillers like morphine, buprenorphine and tramadol are markedly less effective if we don’t know we’re taking them.
  • Individual attitudes and experiences are important, as are cultural factors. Placebo effects are getting stronger in the United States, for example, though not elsewhere.
  • Likely explanations include a growing cultural belief in the effectiveness of painkillers — a result of direct-to-consumer advertising (illegal in most other countries) and perhaps the fact that so many Americans have taken these drugs in the past.
  • Trials show, for example, that strengthening patients’ positive expectations and reducing their anxiety during a variety of procedures, including minimally invasive surgery, while still being honest, can reduce the dose of painkillers required and cut complications.
  • Placebo studies also reveal the value of social interaction as a treatment for pain. Harvard researchers studied patients in pain from irritable bowel syndrome and found that 44 percent of those given sham acupuncture had adequate relief from their symptoms. If the person who performed the acupuncture was extra supportive and empathetic, however, that figure jumped to 62 percent.
  • Placebos tell us that pain is a complex mix of biological, psychological and social factors. We need to develop better drugs to treat it, but let’s also take more seriously the idea of relieving pain without them.
Javier E

Opinion | Scott Pruitt's Attack on Science Would Paralyze the E.P.A. - The New York Times - 0 views

  • It is his latest effort to cripple the agency. Mr. Pruitt, who as Oklahoma’s attorney general described himself as “a leading advocate against the E.P.A.’s activist agenda,” said in an interview published in The Daily Caller last week that he would no longer allow the agency to use studies that include nonpublic scientific data to develop rules to safeguard public health and prevent pollution.
  • Opponents of the agency and of mainstream climate science call these studies “secret science.” But that’s simply not true. Peer review ensures that the analytic methodologies underlying studies funded by the agency are sound.
  • Some of those studies, particularly those that determine the effects of exposure to chemicals and pollution on health, rely on medical records that by law are confidential because of patient privacy policies. These studies summarize the analysis of raw data and draw conclusions based on that analysis. Other government agencies also use studies like these to develop policy and regulations, and to buttress and defend rules against legal challenges. They are, in fact, essential to making sound public policy.
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  • The agency also relies on industry data to develop rules on chemical safety that is often kept confidential for business reasons.
  • So why would he want to prohibit his own agency from using these studies? It’s not a mystery. Time and again the Trump administration has put the profits of regulated industries over the health of the American people. Fundamental research on the effects of air pollution on public health has long been a target of those who oppose the E.P.A.’s air quality regulations, like the rule that requires power plants to reduce their mercury emissions.
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