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Mars Base

First evidence that fear memories can be reduced during sleep - 0 views

medicalxpress.com/...2013-09-evidence-memories.html

scibyte104 brain

shared by Mars Base on 23 Sep 13 - No Cached
  • A fear memory was reduced in people by exposing them to the memory over and over again while they slept
  • It's the first time that emotional memory has been manipulated in humans during sleep
  • potentially offers a new way to enhance the typical daytime treatment of phobias through exposure therapy by adding a nighttime component
  • ...21 more annotations...
  • showed a small but significant decrease in fear
  • If it can be extended to pre-existing fear, the bigger picture is that, perhaps, the treatment of phobias can be enhanced during sleep."
  • Previous projects have shown that spatial learning and motor sequence learning can be enhanced during sleep
  • wasn't previously known that emotions could be manipulated during sleep
  • 15 healthy human subjects received mild electric shocks while seeing two different faces
  • also smelled a specific odorant while viewing each face and being shocked
  • the face and the odorant both were associated with fear
  • Subjects received different odorants to smell with each face such as woody, clove, new sneaker, lemon or mint
  • when a subject was asleep, one of the two odorants was re-presented, but in the absence of the associated faces and shocks.
  • occurred during slow wave sleep when memory consolidation is thought to occur
  • Sleep is very important for strengthening new memories
  • particular odorant was being presented during sleep, it was reactivating the memory of that face over and over again
  • similar to the process of fear extinction during exposure therapy
  • When the subjects woke up, they were exposed to both faces
  • When they saw the face linked to the smell they had been exposed to during sleep, their fear reactions were lower than their fear reactions to the other face
  • Fear was measured in two ways
  • through small amounts of sweat in the skin, similar to a lie detector test
  • through neuroimaging with fMRI (functional magnetic resonance imaging).
  • fMRI results showed changes in regions associated with memory
  • and changes in patterns of brain activity in regions associated with emotion
  • These brain changes reflected a decrease in reactivity that was specific to the targeted face image associated with the odorant presented during sleep
Mars Base

New research aims to teach computers common sense - 0 views

phys.org/...2013-11-aims-common.html

scibyte110 ArtificiaIntelligence

shared by Mars Base on 25 Nov 13 - No Cached
  • Researchers are trying to plant a digital seed for artificial intelligence by letting a massive computer system browse millions of pictures and decide for itself what they all mean
  • The system at Carnegie Mellon University is called NEIL, short for Never Ending Image Learning
  • In mid-July, it began searching the Internet for images 24/7 and, in tiny steps, is deciding for itself how those images relate to each other
  • ...13 more annotations...
  • The goal is to recreate what we call common sense—the ability to learn things without being specifically taught
  • NEIL uses advances in computer vision to analyze and identify the shapes and colors in pictures, but it is also slowly discovering connections between objects on its own
  • the computers have figured out that zebras tend to be found in savannahs and that tigers look somewhat like zebras
  • In just over four months, the network of 200 processors has identified 1,500 objects and 1,200 scenes and has connected the dots to make 2,500 associations
  • Some of NEIL's computer-generated associations are wrong
  • "rhino can be a kind of antelope,"
  • "actor can be found in jail cell"
  • "news anchor can look similar to Barack Obama."
  • having a computer make its own associations is an entirely different type of challenge than programming a supercomputer to do one thing very well, or fast
  • humans constantly make decisions using "this huge body of unspoken assumptions," while computers don
  • humans can also quickly respond to some questions that would take a computer longer to figure out
  • "Could a giraffe fit in your car?" she asked. "We'd have an answer, even though we haven't thought about it" in the sense of calculating the giraffe's body mass
  • In the future, NEIL will analyze vast numbers of YouTube videos to look for connections between objects
Mars Base

Breakthrough therapy allows four paraplegic men to voluntarily move their legs - 0 views

medicalxpress.com/...araplegic-men-voluntarily.html

scibyte126

shared by Mars Base on 08 Apr 14 - No Cached
  • Four young men who have been paralyzed for years achieved
  • moving their legs—as a result of epidural electrical stimulation of the spinal cord
  • All four participants were classified as suffering from chronic, motor complete spinal cord injuries and were unable to move their lower extremities prior to the implantation of an epidural stimulator
  • ...42 more annotations...
  • The stimulator delivers a continuous electrical current to the participants' lower spinal cords, mimicking signals the brain normally transmits to initiate movement
  • an initial study, published in May 2011
  • evaluated the effects of epidural stimulation in the first participant
  • who recovered a number of motor functions as a result of the intervention
  • three years later, the key findings documented
  • detail the impact of epidural stimulation in a total four participants, including new tests
  • What is revolutionary
  • is that the second, third and fourth participants
  • were able to execute voluntary movements immediately following the implantation and activation of the stimulator.
  • The participants' results and recovery time were unexpected, which led researchers to speculate that some pathways may be intact post-injury and therefore able to facilitate voluntary movements.
  • Two of the four subjects were diagnosed as motor and sensory complete injured with no chance of recovery at al
  • Because of epidural stimulation, they can now voluntarily move their hips, ankles and toes
  • groundbreaking for the entire field and offers a new outlook that the spinal cord, even after a severe injury, has great potential for functional recovery.
  • In epidural stimulation, the electrical current is applied at varying frequencies and intensities to specific locations on the lumbosacral spinal cord
  • corresponding to the dense neural bundles that largely control the movement of the hips, knees, ankles and toes
  • With the participants, once the signal was triggered, the spinal cord reengaged its neural network to control and direct muscle movements.
  • When coupling the intervention with rehabilitative therapy, the impact of epidural stimulation intensified
  • Over the course of the study, the researchers noted that the participants were able to activate movements with less stimulation, demonstrating the ability of the spinal network to learn and improve nerve functions
  • uncovered a fundamentally new intervention strategy that can dramatically affect recovery of voluntary movement in individuals with complete paralysis, even years after injury
  • The belief that no recovery is possible and complete paralysis is permanent has been challenged
  • Beyond regaining voluntary movement, the research participants have displayed a myriad of improvements in their overall health
  • increases in muscle mass and regulation of their blood pressure, as well as reduced fatigue and dramatic improvements to their sense of well-being.
  • all four men were able to bear weight independently, as reported by the team
  • The study offers hope that clinical therapies can be developed to advance treatment for the nearly 6 million Americans living with paralysis, including nearly 1.3 million with spinal cord injuries.
  • The four paralyzed participants ranged in neurological level from C7–T5 and were at least two years post-injury at the time of the intervention
  • Two of them had been rated "A" on the American Spinal Injury Association's classification system, meaning they had absolutely no sensation or cognition below the site of their injury
  • surprising the scientists, who believed at least some of the sensory pathway must be intact for epidural stimulation to be successful.
  • With this study, the investigators show that their findings about a motor complete patient regaining movement, as published three years ago in The Lancet, were not an anomaly
  • At the present time,
  • there are no effective evidence-based treatments for chronic spinal cord injury
  • , the implications of this study for the entire field are quite profound, and we can now envision a day when epidural stimulation might be part of a cocktail of therapies used to treat paralysis
  • first learned that a patient had regained voluntary control as a result of the therapy, we were cautiously optimistic
  • The research was funded by the Reeve Foundation and the National Institutes of Health
  • the Leona M. and Harry B. Helmsley Charitable Trust, the Kessler Foundation, the University of Louisville, the Jewish Hospital and St. Mary's Foundation, the Frazier Rehab Institute and University Hospital.
  • Investing in epidural stimulation
  • Now that spinal stimulation has been successful in four out of four patients, there is evidence to suggest a large cohort of individuals,
  • previously with little realistic hope of any meaningful recovery from spinal cord injury, may benefit from this intervention
  • how we see motor complete spinal cord injury
  • don't have to necessarily rely on regrowth of nerves in order to regain function
  • observed this in four out of four people suggests that this is actually a common phenomenon in those diagnosed with complete paralysis
  • The scientists are optimistic that the therapy intervention will continue to result in improved motor functions
  • based on observations from the research, there is strong evidence that with continued advancements of the epidural stimulator, individuals with complete spinal cord injuries will be able to bear weight independently, maintain balance and work towards stepping
Mars Base

Astronomers find tantalizing hints of a potentially habitable exoplanet - 0 views

phys.org/...nts-potentially-habitable.html

scibyte71 exoplanet

shared by Mars Base on 14 Nov 12 - No Cached
  • previously been found to hold three "super-Earth" exoplanets in close orbit
  • researchers poring over data from ESO's HARPS planet-hunting instrument are suggesting that there are likely at least six super-Earth exoplanets
  • one of them appearing
  • ...10 more annotations...
  • into the star's water-friendly "Goldilocks" zone
  • HARPS (High Accuracy Radial velocity Planet Searcher) on ESO's La Silla 3.6m telescope is a dedicated exoplanet hunter
  • detect the
  • slight wobble of a star caused by the gravitational tug of orbiting planets
  • HD 40307 g is located far enough away from its star to likely not be tidally locked
  • it wouldn't have one side subject to constant heat and radiation while its other "far side" remains cold and dark
  • the estimated 7-Earth-mass exoplanet receives around 62% of the radiation that Earth gets from the Sun
  • HD 40307 g is still a candidate—more observations are needed to not only confirm its existence but also to find out exactly what kind of planet it may be.
  • more detailed characterization of this candidate is very unlikely using ground based studies because it is very unlikely [sic] to transit the star, and a direct imaging mission seems the most promising way of learning more
  • just finding potential Earth-sized worlds in a system like HD 40307′s is a big deal for planetary scientists
Mars Base

Love Of Spicy Food Is Built Into Your Personality | Popular Science - 0 views

www.popsci.com/...cy-food-built-your-personality

scibyte74 Personality

shared by Mars Base on 06 Dec 12 - No Cached
  • But the science of spicy food liking and intake
  • shows there’s more to it than just increased tolerance with repeated exposure
  • research dating back at least to the 1980s
  • ...18 more annotations...
  • Personality, researchers say, is also a factor in whether a person enjoys spicy meals and how often he or she eats them
  • desensitization to capsaicin, the plant chemical that gives peppers their burn, is well documented, there’s also evidence that the effect is surprisingly small
  • researchers have previously linked chili liking to thrill seeking, specifically an affinity for amusement park rides and gambling
  • investigators found a relationship between chili liking and sensation seeking when using a more formal measure of personality called Zuckerman’s Sensation Seeking Scale
  • In both cases, however, the associations were fairly weak, and neither study looked at intake -- how often a person eats spicy foods, versus how much a person likes spice.
  • used an updated measure of sensation seeking that avoided gender- and age-biased questions
  • Sensation seeking emerged as a much stronger predictor of spicy food liking than in the previous studies
  • it also predicted how often a person ate chili-laden meals
  • personality trait, however, was not associated with high liking of non-spicy foods, which reduced the possibility that thrill seekers are just crazy about food in general
  • frequent chili eaters didn’t feel the burn from the capsaicin sample any less than people who ate peppers less often
  • The study group may not have been large enough to show a desensitization effect
  • lack of evidence for desensitization in the study boosts the argument for personality as an important factor
  • combination of factors influences who goes for the mild wings on Super Bowl Sunday and who reaches for hot
  • childhood exposure and learning all play a critical role in liking for spicy foods
  • also individuals who acquired an entirely [new] set of food preferences as adults once they moved away from home
  • may have been a disconnect between reported frequency of intake and actual dose
  • Ninety-seven male and female participants ranging in age from 18 to 45 filled out a food-liking questionnaire
  • rated the intensity of sensations after sampling six stimuli, including capsaicin mixed in water
Mars Base

Physicists use Kinect to control holographic tweezers (w/ Video) - 0 views

phys.org/...olographic-tweezers-video.html

scibyte70 Kinect

shared by Mars Base on 05 Nov 12 - No Cached
  • Researchers
  • in Scotland have devised a means of using a Microsoft Kinect sensing system to allow for hand control of holographic optical tweezers
  • Laser tweezers are laser based devices that allow for manipulation of very small objects; typically at the cellular level
  • ...12 more annotations...
  • A laser beam is projected towards a target, but before reaching it, is split into three separate beams
  • three beams are broadcast onto the edges of the object to be manipulated
  • as the beams are moved the object is caused to move in lockstep
  • , fine tuning control of the laser to cause the movement of an object has been less than ideal
  • researchers to continue looking for alternative means
  • In this new research, the team connected a Microsoft Kinect device to the tweezers and then demonstrated an ability to move microscopic sized objects by moving their hands around in the air.
  • connecting a Kinect device to their virtual tweezers, the researchers found that they were able to define the space in which they wished to work by using simple hand movements and then to connect, virtually to a particular tiny object
  • The Kinect
  • is not precise enough to capture subtle movements however
  • doesn't allow for force-feedback, or the ability to feel the resistance of an object as its being moved
  • HoloHands, is not sophisticated enough to allow for serious research work
  • being used as a tool for educational purposes, either as a tool, or implemented as a learning game.
Mars Base

Numbers Games Devised to Aid People with "Dyscalculia": Scientific American - 0 views

www.scientificamerican.com/article.cfm

scibyte78 Dyscalculia

shared by Mars Base on 19 Jan 13 - No Cached
  • By developing treatments for dyscalculia
  • to test competing theories about the cognitive basis of numeracy. If,
  • dyscalculia is at heart a deficiency of basic number sense and not of memory, attention or language, as others have proposed, then nurturing the roots of number sense should help dyscalculics
  • ...12 more annotations...
  • It may be the case that what these kids need is just much more practice than the rest of us
  • starts with a game involving a number line
  • “What is the number that is right in the middle between 200 and 800? Do you know it?
  • A classic sign of dyscalculia is difficulty in grasping the place-value system,
  • A soft computer voice tells Christopher to “find the number and click it
  • The game involves zooming in and zooming out to rescale the number line
  • talks through each move — a strategy that Babtie encourages
  • but it takes him more than a minute to locate 210. His classmates, meanwhile, are learning to multiply two-digit numbers.
  • Butterworth
  • made his name probing obscure speech and language disorders
  • tested 31 eight- and nine-year-old children who were near the bottom of their class in mathematics but did well enough in other subjects.
  • Compared with normal children and those with dyslexia, the dyscalculic children struggled on almost every numerical task, yet were average on tests of reading comprehension, memory and IQ.
Mars Base

NASA - Curiosity Rover Hits Paydirt - 0 views

www.nasa.gov/...curiosity20130315.html

scibyte86 Curiosity

shared by Mars Base on 17 Mar 13 - No Cached
  • This week the Curiosity science team released its initial findings from its first ever drilled sample on Mars
  • Curiosity obtained her first drill sample and passed that sample on to her onboard analytical lab instruments, called CheMin and SAM
  • These powerful instruments tell us about what minerals are present in these rocks and whether they contain the ingredients necessary to sustain life as we know it.
  • ...9 more annotations...
  • When we combine what we have learned from our remote sensing and contact science instruments with the data that's coming in from CheMin and SAM, we get a picture of an ancient watery environment, which would have been habitable had life been present in it.
  • the information that we're getting from the CheMin instrument, tells us that the minerals that are present in this lakebed sedimentary rock at John Klein are very different from just about anything we've ever analyzed before on Mars
  • they tell us that the John Klein rock was deposited in a fresh water environment
  • This is an important contrast with other sedimentary environments that we've visited on Mars, like the Meridiani Planum landing site where the Mars Exploration Rover, Opportunity, has been operating since 2004.
  • At that site, the sedimentary rocks record evidence of an environment that was only wet on a very intermittent basis, and when it was, the waters that were there were highly acidic, very salty, and not favorable for the survival of organic compounds.
  • direct contrast to the fresh water environment we're seeing here at the John Klein Site
  • The SAM instrument is telling us that these rocks contained all of the ingredients necessary for a habitable environment
  • We found carbon, sulfur and oxygen, all present and a number of other elements in states that life could have taken advantage of.
  • these few tablespoons of powder from a Martian rock have provided the Curiosity science team with an exciting new dataset
Mars Base

Dog sniffs out grammar | Psychology | Science News - 0 views

www.sciencenews.org/...Dog_sniffs_out_grammar

scibyte95

shared by Mars Base on 22 May 13 - No Cached
  • Chaser isn’t just a 9-year-old border collie
  • She’s a grammar hound.
  • In experiments directed by her owner
  • ...21 more annotations...
  • Chaser demonstrated her grasp of the basic elements of grammar by responding correctly to commands such as “to ball take Frisbee” and its reverse, “to Frisbee take ball.”
  • The dog had previous, extensive training to recognize classes of words including nouns, verbs and prepositions
  • Throughout the first three years of Chaser’s life, Pilley and a colleague trained the dog to recognize and fetch more than 1,000 objects by name
  • researchers also taught Chaser the meaning of different types of words, such as verbs and prepositions
  • Chaser learned that phrases such as “to Frisbee” meant that she should take whatever was in her mouth to the named object.
  • Exactly how the dog gained her command of grammar is unclear
  • suspects that
  • first mentally linked each of two nouns she heard in a sentence to objects in her memory. Then
  • held that information in mind while deciding which of two objects to bring to which of two other objects.
  • Chaser started sentence training at age 7. She stood facing a pair of objects she knew by name
  • An experimenter would say, for instance, “to ball take Frisbee.” In initial trials, the experimenter pointed at each item while saying its name.
  • After several weeks of training, two experiments conducted
  • had to choose an object from one pair to carry to an object from the other pair
  • read commands that included words for those objects. Only some of those words had been used during sentence training
  • To see whether Chaser grasped that grammar could be used flexibly
  • student also read sentences in the reversed form of “take sugar to decoy.”
  • In 28 of 40 attempts, Chaser grabbed the correct item in her mouth and dropped it next to the correct target.
  • Another experiment tested Chaser’s ability to understand commands when she couldn’t see the objects at first
  • with two objects behind her at the other end of the bed
  • After hearing a command, Chaser turned around and nabbed one of the objects.
  • then ran to the living room and delivered the item to one of another pair of objects. She succeeded on all 12 trials
Mars Base

Video Transcript: Curiosity's Cameras - NASA Jet Propulsion Laboratory - 0 views

www.jpl.nasa.gov/...video-transcript.php

scibyte98 Curiosity

shared by Mars Base on 18 Jun 13 - No Cached
  • received a lot of questions about the cameras on the rovers and we're here to answer some of those questions
  • The Curiosity rover actually has 17 cameras on it, which is the most of any NASA planetary mission ever.
  • took pictures as the rover was landing on Mars
  • ...13 more annotations...
  • MARDI, or the Mars Descent Imager,
  • is the camera mounted on the end of the arm, and that takes close-up, high-resolution color photos
  • MAHLI
  • hazard avoidance cameras, or the HazCams. There are four of these in the front and four in the back, and they're used to take pictures of the terrain near the wheels and nearby the rover
  • Navigation Cameras, which take pictures that are used to drive the rover
  • Mast Cameras, which are color imagers, which are used to do geology investigations
  • the remote microscopic imager, which is part of the ChemCam laser instrument. And that's used to document the laser spots, that the rover makes on the surface
  • Many of the black and white images that come back from the rover are
  • black and white, or gray scale as we call it, is because that's all the rover really needs in order to detect rocks and other obstacles
  • Other cameras are color, such as the Mastcam imager, and the reason that they're color is because the scientists use the color information to learn about the soil and the rocks
  • There are 1-megapixel black and white imagers for the engineering cameras and 2-megapixel color imagers for the science cameras
  • In addition to the video that we took when the rover descending on to the surface, we've taken movies of the soil being shaken in the scoop.
  • files are pretty large and because we have a limited downlink each day, the scientists prefer to take still images of new targets
Mars Base

New drug reverses loss of brain connections in Alzheimer's disease - 0 views

medicalxpress.com/...rses-loss-brain-alzheimer.html

scibyte99 Alzheimer

shared by Mars Base on 18 Jun 13 - No Cached
  • The first experimental drug to boost brain synapses lost in Alzheimer's disease
  • combines two FDA-approved medicines to stop the destructive cascade of changes in the brain that destroys the connections between neurons, leading to memory loss and cognitive decline.
  • The decade-long study
  • ...21 more annotations...
  • shows that NitroMemantine can restore synapses, representing the connections between nerve cells (neurons) that have been lost during the progression of Alzheimer's in the brain
  • These findings actually mean that you might be able to intercede not only early but also a bit later
  • Alzheimer's patient may be able to have synaptic connections restored even with plaques and tangles already in his or her brain.
  • study, conducted in animal models as well as brain cells derived from human stem cells,
  • team mapped the pathway that leads to synaptic damage in Alzheimer
  • found that amyloid beta peptides, which were once thought to injure synapses directly
  • actually induce the release of excessive amounts of the neurotransmitter glutamate from brain cells called astrocytes that are located adjacent to the nerve cells.
  • Normal levels of glutamate promote memory and learning, but excessive levels are harmful
  • Alzheimer's disease, excessive glutamate activates extrasynaptic receptors, designated eNMDA receptors
  • which get hyperactivated and in turn lead to synaptic loss
  • lab had previously discovered how a drug called memantine can be targeted to eNMDA receptors to slow the hyperactivity seen in Alzheimer's.
  • memantine's effectiveness has been limited.
  • memantine—a positively charged molecule—is repelled by a similar charge inside diseased neurons
  • memantine gets repelled from its intended eNMDA receptor target on the neuronal surface.
  • FDA approval of memantine in 2003
  • a fragment of the molecule nitroglycerin—a second FDA-approved drug commonly used to treat episodes of chest pain or angina in people with coronary heart disease—could bind to another site that the Lipton group discovered on NMDA receptors.
  • memantine rather selectively binds to eNMDA receptors, it also functions to target nitroglycerin to the receptor
  • by combining the two, Lipton's lab created a new, dual-function drug
  • researchers developed 37 derivatives of the combined drug before they found one that worked
  • By shutting down hyperactive eNMDA receptors on diseased neurons, NitroMemantine restores synapses between those neurons
  • NitroMemantine brings the number of synapses all the way back to normal within a few months of treatment in mouse models of Alzheimer's disease. In fact, the new drug really starts to work within hours
Mars Base

Specialized nerve fibers send touchy-feely messages to brain | Body & Brain | Scien... - 0 views

www.sciencenews.org/...touchy-feely_messages_to_brain

scibyte80 TouchMessages

shared by Mars Base on 31 Jan 13 - No Cached
  • Some nerve fibers seem to love a good rubdown. These tendrils, which spread across skin like upside-down tree roots, detect smooth, steady stroking and send a feel-good message to the brain
  • The results are the latest to emphasize the strong and often underappreciated connection between emotions and the sensation of touch
  • “It may seem frivolous to be studying massage neurons in mice, but it raises a profound issue — why do certain stimuli feel a certain way?”
  • ...16 more annotations...
  • . Earlier studies in people suggested that a particular breed of nerve fibers detects a caress and carries that signal to the brain
  • scientists hadn’t been able to directly link this type of neuron to good feelings, either in people or in animals.
  • Directly linking these neurons with pleasure clarifies the importance of touch
  • The new study relied on mice genetically engineered so that a select population of nerve cells would glow when they sensed a caress
  • These neurons,
  • possessed the attributes of massage sensors, but they stubbornly refused to respond to touch in experiments in lab dishes
  • by touching the genetically engineered animals’ skin, the researchers were able to study these cells in live mice.
  • A harsher poke, with a more focused point of pressure, didn’t elicit a reaction from the cells
  • These neurons, which all carry a protein called MRGPRB4, seem tuned to detect a steady stroke
  • the researchers tested whether this stroke felt good to mice
  • the scientists used a different kind of genetically engineered mouse, one with caress-sensitive neurons that a drug could activate
  • When the researchers dispensed the drug in a particular room, the mice soon learned to prefer that room over others
  • associating it with the presumably enjoyable sensation of being stroked
  • not yet clear whether the nerve fibers in the mice have exact analogs in humans,
  • new view of caress detection
  • offers a deeper understanding of touch.
Mars Base

First Evidence of Life in Antarctic Subglacial Lake : The Crux - 0 views

blogs.discovermagazine.com/...e-in-antarctic-subglacial-lake

scibyte80 AntarcticLake

shared by Mars Base on 01 Feb 13 - No Cached
  • The search continues for life in subglacial Lake Whillans, 2,600 feet below the surface of the West Antarctic Ice Sheet—but a thrilling preliminary result has detected signs of life
  • At 6:20am on January 28, four people in sterile white Tyvek suits tended to a winch winding cable onto the drill platform
  • One person knocked frost off the cable as it emerged from the ice borehole a few feet below
  • ...24 more annotations...
  • a gray plastic vessel, as long as a baseball bat, filled with water from Lake Whillans, half a mile below.
  • The bottle was hurried into a 40-foot cargo container outfitted as a laboratory on skis
  • Some of the lake water was squirted into bottles of media in order to grow whatever microbes might inhabit the lake
  • cultures could require weeks to produce results
  • When lake water was viewed under a microscope, cells were seen: their tiny bodies glowed green in response to DNA-sensitive dye. It was the first evidence of life in an Antarctic subglacial lake.
  • (A Russian team has reported that two types of bacteria were found in water from subglacial Lake Vostok, but DNA sequences matched those of bacteria that are known to live inside kerosene—causing the scientists to conclude that those bacteria came from kerosene drilling fluid used to bore the hole, and not from Lake Vostok itself
  • In order to conclusively demonstrate that Lake Whillans harbors life, the researchers will need to complete more time-consuming experiments showing that the cells actually grow
  • dead cells can sometimes show up under a microscope with DNA-sensitive
  • weeks or months will pass before it is known whether these cells represent known types of microbes, or something never seen before
  • t a couple of things seem likely. Most of those microbes probably subsist by chewing on rocks. And despite being sealed beneath 2,600 feet of ice, they probably have a steady supply of oxygen.
  • oxygen comes from water melting off the base of the ice sheet—maybe a few penny thicknesses of ice per year
  • When you melt ice, you’re liberating the air bubbles [trapped in that ice
  • That’s 20 percent oxygen
  • , lake bacteria could live on commonly occurring pyrite minerals that contain iron and sulfur
  • would obtain energy by using oxygen to essentially “burn” that iron and sulfur (analogous to the way that animals use oxygen to slowly burn sugars and fats).
  • The half mile of glacial ice sitting atop Lake Whillans is quite pure—derived from snow that fell onto Antarctica thousands of years ago.
  • contains only one-hundredth the level of dissolved minerals that are seen in a clear mountain creek, or in tap water from a typical city
  • a sensor lowered down the borehole this week showed that dissolved minerals were far more abundant in the lake itself
  • The fact that we see high concentrations is suggestive that there’s some interesting water-rock-microbe interaction that’s going on
  • Microbes, in other words, might well be munching on minerals under the ice sheet
  • will take months or years to unravel this picture
  • will perform experiments to see whether microbes taken from the lake metabolize iron, sulfur, or other components of minerals
  • will analyze the DNA of those microbes to see whether they’re related to rock-chewing bacteria that are already known to science.
  • Antarctica isn’t the only place in the solar system where water sits concealed in the dark beneath thick ice. Europa and Enceladus (moons of Jupiter and Saturn, respectively) are also thought to harbor oceans of liquid water. What is learned at Lake Whillans could shed light on how best to look for life in these other places
Mars Base

Researchers find clues to how the brain decides when to rest - 0 views

medicalxpress.com/...2013-01-clues-brain-rest.html

scibyte80 Learning

shared by Mars Base on 22 Jan 13 - No Cached
  • A team of researchers
  • has found what they call a "signal" that tells a person when to rest while engaging in work, and then when to resume once rested
  • used fMRI scans on a group of volunteers to study a part of the brain normally associated with pain perception and found what amounts to a signal calling for the conscious mind to take a break
  • ...10 more annotations...
  • Scientists studying how people make decisions regarding work have over time devised theories of cost versus benefit scenarios to describe what causes people to engage in work activities, or to not
  • Not so well studied is how people come to decide when it's time to take a break
  • researchers enlisted the aid of 39 participants who were asked to squeeze a spring-loaded handgrip over and over as they underwent fMRI scans
  • Each was promised a monetary reward for doing so based on a sliding scale. The longer they squeezed, the better the reward would be
  • In analyzing the fMRI images, the researchers discovered that activity in a part of the brain called the posterior insula (normally associated with pain perception), built over time as the volunteers continued squeezing – a signal of sorts
  • grew during effort, and then faded during rest times – peaking just before resting
  • researchers suggest that when a certain peak is reached, the rest of the brain is alerted to the need to take a break
  • The team also found that increasing the difficulty of the squeezing led to the signal increasing at a faster rate, but slowed when a bigger reward was offered despite the increased workload
  • They also found that bumping up the reward during a rest period caused the lowest signal point to come more quickly, indicating that rest time was up sooner than it would have been otherwise
  • suggest that their observations indicate that they brain is constantly engaged in a struggle to maximize reward, while simultaneously minimizing the amount of work needed to get that reward, and uses rests stops to help it get there in a manner best suited to the work at hand.
Mars Base

Study shows red pen use by instructors leads to more negative response - 0 views

phys.org/...ructors-negative-response.html

scibyte79 RedPen

shared by Mars Base on 23 Jan 13 - No Cached
  • Sociologists
  • claim in a paper they've had published
  • that when teachers use a red pen to add comments to student papers, students perceive them more negatively than if they use another color pen
  • ...12 more annotations...
  • the two researchers enlisted the assistance of 199 undergraduate students – each was given four versions of an already graded essay by an unknown instructor
  • graded remarks were deemed as high or low in quality with some written in red, others in blue
  • students were asked to read the essay and the remarks given by the instructor and then to rate how they felt about what the instructor had written and to suggest what grade they would have given the essay
  • also asked how they felt about the instructor that had written the original remarks
  • After they'd finished with their opinions, each was also given a questionnaire designed to provide the researchers with more concrete data.
  • the researchers found that the student volunteers didn't seem to be impacted one way or another by pen color when they agreed with the instructor's comments and grade
  • But when they disagreed, there were definitely some differences – mainly negative
  • When the instructors' comments were written in red versus blue the volunteers judged them more harshly and as a result, rated them lower in "bedside manner."
  • the volunteers didn't seem to judge the quality of the comments any differently – their negative feelings were aimed at the person that had written the remarks when they wrote in red ink
  • theorize that red ink is akin to using all caps when writing e-mail or text messages – it's like shouting at a person
  • those on the other end quite naturally feel a little bit abused and respond by growing angry or sad, which, they note, doesn't really promote the learning process
  • suggest instructors stop using red pens and go with a shade of blue instead
Mars Base

InteraXon looking for crowdfunding for Muse, a brainwave-sensor headband (w/ Video) - 0 views

phys.org/...brainwave-sensor-headband.html

scibyte69

shared by Mars Base on 24 Oct 12 - No Cached
  • crowd source funding site
  • Muse is a headband device based on electroencephalography (EEG) sensor technology combined with a sophisticated smartphone app that allows the wearer's brainwaves to be monitored.
  • sensors
  • ...4 more annotations...
  • monitor alpha (resting state) and beta (active state) brainwaves
  • converted to a signal that is broadcast, via Bluetooth technology, to the user's smartphone
  • claims that Muse can be used to learn new ways to relax, recognize lapses in concentration, build self-confidence, and gain more control of one's thoughts, overall
  • app includes a series of lessons and exercises designed to teach the user how to manipulate brain waves using visual feedback
Mars Base

Zoom Through 84 Million Stars in Gigantic New 9-Gigapixel Image - 0 views

www.universetoday.com/...gigantic-new-9-gigapixel-image

scibyte69 media

shared by Mars Base on 24 Oct 12 - No Cached
  • new gigantic nine-gigapixel image from the VISTA infrared survey telescope at ESO’s Paranal Observatory of the central portion of the Milky Way Galaxy
  • resolution of this image is so great, that if it was printed out in the resolution of a typical book, it would be 9 meters long and 7 meters tall
  • The huge dataset contains more than ten times more stars than previous studies
  • ...4 more annotations...
  • By observing
  • we can learn a lot more about the formation and evolution of not only our galaxy, but also spiral galaxies in general
  • To help analyze this huge catalogue, the brightness of each star is plotted against its color for about 84 million stars to create a color–magnitude diagram
  • plot contains more than ten times more stars than any previous study
Mars Base

Auroras Seen on Uranus For First Time - 0 views

news.nationalgeographic.com/...s-auroras-science-space-hubble

AprMedia scibyte43 hubble uranus

shared by Mars Base on 20 Apr 12 - No Cached
  • Two fleeting, Earth-size auroral storms were imaged by the Hubble Space Telescope as they flared up on the dayside of the gas giant in November 2011. (
  • Auroras tend to surround a planet's poles, where magnetic field lines converge and funnel incoming charged solar particles into the planet's atmosphere. There, the particles collide with air molecules, making the molecules glow
  • Scientists tried unsuccessfully to detect auroras on Uranus in 1998 and 2005
  • ...5 more annotations...
  • team learned of an impending solar storm directed toward Uranus, which sits about 2.5 billion miles (4 billion kilometers) from Earth.
  • timed their Hubble observations specifically to coincide with the solar storm, and about six weeks later, Hubble spotted the auroras flaring up in Uranus's upper atmosphere
  • the other seven planets, Uranus's magnetic axis is 60 degrees off from its spin axis
  • spin axis itself has a bizarre 98-degree tilt relative to the solar system's orbital plane
  • , the planet seems to roll around on its side as it orbits the sun.
Mars Base

Light From a 'SuperEarth' Detected for the First Time - 0 views

www.universetoday.com/...th-detected-for-the-first-time

scibyte46 Spitzer exoplanet

shared by Mars Base on 09 May 12 - No Cached
  • 55 Cancri
  • one of the first known stars to host an extrasolar planet
  • discovered via radial velocity measurements in 2004
  • ...13 more annotations...
  • astronomers were able to determine its mass and radius
  • Spitzer became the first telescope to detect light from a planet beyond our solar system, when it saw the infrared light of a “hot Jupiter
  • NASA’s Hubble and Kepler space telescopes
  • using the same method
  • In this method, a telescope gazes at a star as a planet circles behind it. When the planet disappears from view, the light from the star system dips ever so slightly, but enough that astronomers can determine how much light came from the planet itself
  • information reveals the temperature of a planet, and, in some cases, its atmospheric components
  • other current planet-hunting methods obtain indirect measurements of a planet by observing its effects on the star.
  • about 8.57 Earth masses
  • radius is 1.63 times that of Earth
  • density is 10.9 ± 3.1 g cm-3 (the average density of Earth is 5.515 g cm-3),
  • Cancri e is tidally locked, so one side always faces the star
  • James Webb Space Telescope, scheduled to launch in 2018, likely will be able to learn even more about the planet’s composition
  • might be able to use a similar infrared method to Spitzer to search other potentially habitable planets for signs of molecules possibly related to life.
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