Skip to main content

Home/ SciByte/ Group items tagged scibyte45

Rss Feed Group items tagged

Filter: All | Bookmarks | Topics Simple Middle
Mars Base

Neuro researchers sharpen our understanding of memories - 0 views

medicalxpress.com/...05-neuro-sharpen-memories.html

scibyte45 brain memories

shared by Mars Base on 01 May 12 - No Cached
  • Scientists now have a better understanding of how precise memories are formed
  • these findings could help us to better understand memory impairments in neurodegenerative disorders like Alzheimer's disease
  • study looks at the cells in our brains, or neurons, and how they work together as a group to form memories
  • ...11 more annotations...
  • neurons are classified into two groups according to the type of chemical they produce: excitatory, who produce chemicals that increase communication between neurons, and inhibitory, who have the opposite effect, decreasing communication
  • Scientists knew that inhibitory cells enable us to refine our memories, to make them specific to a precise set of information
  • findings explain for the first time how this happens at the molecular and cell levels
  • very little research has been done on inhibitory neurons, partly because they are very difficult to study
  • In the laboratory, we simulated the formation of a new memory by using chemicals
  • measured the electrical activity within the network of cells
  • cells where we had removed CREB, we saw that the strength of the electrical connections was much weaker
  • scientists found that a factor called "CREB" plays a key role in adjusting gene expression and the strength of synapses in inhibitory neurons
  • when we increased the presence of CREB, the connections were stronger
  • This new understanding of the chemical functioning of the brain may one day lead to new treatments
  • we are unfortunately many years away from developing new treatments from this information."
Mars Base

ScienceShot: There's Cow in Your Smog - ScienceNOW - 0 views

news.sciencemag.org/...ceshot-theres-cow-in-your.html

scibyte45 smog

shared by Mars Base on 03 May 12 - No Cached
  • people typically blame Southern California's smog on automobiles, a new study suggests that cows may be just as responsible, if not more so
  • large fraction of the region's smog, especially the particles smaller than 2.5 micrometers in diameter, is ammonium nitrate
  • particles form in the atmosphere when ammonia, which is generated by cars with certain types of catalytic converters and by bacteria that consume cattle waste, reacts with nitrogen oxides that are produced in large quantities in automobile emissions
  • ...3 more annotations...
  • Data gathered during low-altitude flights in and around the Los Angeles basin in May 2010 suggest that the region's 9.9 million autos generate about 62 metric tons of ammonia each day
  • ammonia emissions from dairy farms in the eastern portion of the basin—home to about 298,000 cattle—range between 33 and 176 metric tons per day
  • Ammonia emissions from the dairy farms are concentrated, boosting atmospheric levels of the gas to more than 100 times background levels, so efforts to curb the farms' emissions (perhaps by feeding the animals different diets) might reduce smog more than those targeting cars.
Mars Base

Delay Likely for SpaceX's Private Launch to Space Station | Space.com - 0 views

www.space.com/pace-capsule-launch-delay.html

scibyte45 SpaceX iss PrivateSpaceTravel

shared by Mars Base on 03 May 12 - No Cached
  • : 02 May 2012
  • SpaceX was targeting the launch for Monday, May 7, but now will likely shift to a later date, possibly May 10
  • "At this time, a May 7th launch appears unlikely," SpaceX spokeswoman Kirstin Brost Grantham wrote in a statement. "SpaceX is continuing to work through the software assurance process with NASA. We will issue a statement as soon as a new launch target is set.
  • ...1 more annotation...
  • The flight was previously delayed from an April 30 launch date to allow more time for tests of Dragon's flight software. The new delay is also meant to allow for further checkouts.
Mars Base

Supermassive Black Hole Swallows Star | Hungry Black Holes | Space.com - 0 views

www.space.com/-black-hole-swallows-star.html

scibyte45 black holes star

shared by Mars Base on 03 May 12 - No Cached
  • star whose death may ultimately provide more clues on the inner workings of the enigmatic gravitational monster that devoured it.
  • In June 2010, the researchers spotted a bright flare from the previously dormant black hole at the center of a galaxy approximately 2.7 billion light-years away.
  • The flare of light reached peak brightness a month after it was detected, then slowly faded over the next 12 months
  • ...12 more annotations...
  • By measuring the rise of the flare's brightness, the scientists calculated the rate at which the star's gas was getting sucked into the black hole
  • helped reveal at what point and time the black hole had begun disrupting the star, revealing how powerful its gravitational field was and thus its mass.
  • estimate the black hole's mass to be 3 million suns
  • like we are gathering evidence from a crime scene
  • analyzed the spectrum of the ejected gas — that is, the specific colors making up its light
  • using data from the Multiple Mirror Telescope Observatory on Mount Hopkins in Arizona
  • and the spectrum of the gas revealed it was mostly helium.
  • unique spectral fingerprint
  • fact there was mostly helium and very little hydrogen in the gas suggests "the slaughtered star had to have been the helium-rich core of a stripped star
  • This likely happened when the star went through the red giant phase, where it expanded to 100 times its original radius
  • it puffed up like that, it became vulnerable to the gravitational tidal forces of the black hole, and it would have been very easy to strip off the tenuous hydrogen envelope
  • the star then had to approach much closer, 100 times closer in, before it was completely disrupted by the black hole
Mars Base

A Star Is Torn - Science News - 0 views

www.sciencenews.org/...A_star_is_torn

scibyte45 black holes star

shared by Mars Base on 03 May 12 - No Cached
  • In spring 2010, NASA’s orbiting Galaxy Evolution Explorer and the ground-based Pan-STARRS telescope observed a suspicious brightening around a supermassive black hole parked more than 2 billion light-years from Earth
  • Over the next few months, the flare continued increasing in brightness — then it dimmed
  • Scientists now suggest that the light show was evidence of the black hole PS1-10jh shredding a star that wandered too close
  • ...7 more annotations...
  • analysis presented online May 2 in Nature indicates that at the time of engulfment, the star was just a helium-rich core, the remainder of a former red giant
  • The black hole
  • weighing about 3 million solar masses, had probably already snacked on the star’s outer layers during a previous close encounter.
  • the black hole spat some of the stellar material into space
  • followed elongated orbits that eventually dumped them back into the black hole, producing the observed, months-long flare.
  • Such disruption events are rare, thought to occur only once every 10,000 years per galaxy
  • can help astronomers spot otherwise hidden black holes.
Mars Base

Game on! Researchers use online crowd-sourcing to diagnose malaria - 0 views

medicalxpress.com/...ne-crowd-sourcing-malaria.html

scibyte45 crowdsourcing medical

shared by Mars Base on 03 May 12 - No Cached
  • Online crowd-sourcing — in which a task is presented to the public, who respond, for free, with various solutions and suggestions — has been used to evaluate potential consumer products, develop software algorithms and solve vexing research-and-development challenges. But diagnosing infectious diseases
  • crowd-sourced online gaming system in which players distinguish malaria-infected red blood cells from healthy ones by viewing digital images obtained from microscopes.
  • recognize infectious diseases with the accuracy of trained pathologists
  • ...16 more annotations...
  • UCLA Henry Samueli School of Engineering and Applied Science
  • Working on the assumption that large groups of public non-experts can be trained to recognize infectious diseases with the accuracy of trained pathologists
  • School of Medicine at UCLA
  • found that a small group of non-experts playing the game (mostly undergraduate student volunteers) was collectively able to diagnosis malaria-infected red blood cells with an accuracy that was within 1.25 percent of the diagnostic decisions made by a trained medical professional.
  • The game, which can be accessed on cell phones and personal computers, can be played by anyone around the world, including children
  • if you carefully combine the decisions of people — even non-experts — they become very competitive
  • if you just look at one person's response, it may be OK, but that one person will inevitably make some mistakes. But if you combine 10 to 20, maybe 50 non-expert gamers together, you improve your accuracy greatly in terms of analysis
  • could potentially help overcome limitations in the diagnosis of malaria
  • current gold standard for malaria diagnosis involves a trained pathologist using a conventional light microscope to view images of cells and count the number of malaria-causing parasites
  • process is very time-consuming, and given the large number of cases in resource-poor countries, the sheer volume presents a big challenge
  • significant portion of cases reported in sub-Sahara Africa are actually false positives, leading to unnecessary and costly treatments and hospitalizations
  • t the same platform could be applied to combine the decisions of minimally trained health care workers to significantly boost the accuracy of diagnosis, which is especially promising for telepathology, among other telemedicine field
  • By training hundreds, and perhaps thousands, of members of the public to identify malaria through UCLA's crowd-sourced game, a much greater number of diagnoses could be made more quickly — at no cost and with a high degree of collective accurac
  • research group created an automated algorithm for diagnosing the same images using computer vision, as well as a novel hybrid platform for combining human and machine resources toward efficient, accurate and remote diagnosis of malaria.
  • Before playing the game, each player is given a brief online tutorial and an explanation of what malaria-infected red blood cells typically look like using sample images
  • one of the major challenges will be the skepticism of traditional microscopists, pathologists and clinical laboratory personnel, not to mention malaria experts, who will initially view with suspicion a gaming approach in malaria diagnostics
Mars Base

Four white dwarf stars caught in the act of consuming 'earth-like' exoplanets - 0 views

phys.org/...rf-stars-caught-consuming.html

scibyte45 exoplanet

shared by Mars Base on 04 May 12 - No Cached
  • astrophysicists have pinpointed four white dwarf stars surrounded by dust from shattered planetary bodies which once bore striking similarities to the composition of the Earth
  • White dwarfs are the final stage of life of stars like our Sun, the residual cores of material left behind after their available fuel for nuclear reactions has been exhausted
  • researchers found that the most frequently occurring elements in the dust around these four white dwarfs were oxygen, magnesium, iron and silicon – the four elements that make up roughly 93 per cent of the Earth.
  • ...8 more annotations...
  • even more significant observation was that this material also contained an extremely low proportion of carbon, which matched very closely that of the Earth and the other rocky planets orbiting closest to our own Sun
  • first time that such low proportions of carbon have been measured in the atmospheres of white dwarf stars
  • clear evidence that these stars once had at least one rocky exoplanet which they have now destroyed
  • must also pinpoint the last phase of the death of these worlds.
  • atmosphere of a white dwarf is made up of hydrogen and/or helium
  • heavy elements that come into their atmosphere are dragged downwards to their core and out of sight within a matter of days
  • astronomers must literally be observing the final phase of the death of these worlds as the material rains down on the stars at rates of up to 1 million kilograms every second.
  • clear evidence that these stars once had rocky exoplanetary bodies which have now been destroyed
Mars Base

2012 Venus Transit - The Countdown Is On! - 0 views

www.universetoday.com/...us-transit-the-countdown-is-on

scibyte45 venus transit scibyte49 scibyte48

shared by Mars Base on 04 May 12 - No Cached
  • On June 5 (June 6 in Australia and Asia), it will pass between the Earth and Sun… an event which only happens about twice and century and won’t happen again until the year 2117!
  • now is the time to begin your preparations to view the transit of Venus.
  • Because the transit of Venus is such a rare event, many retailers are carrying special eclipse/transit viewing glasses
  • ...9 more annotations...
  • appear much like the cardboard 3D glasses you get at the movie theatre, but instead of red and blue lenses, they will have either black mylar or Baader filter film.
  • inspect the edges carefully to make sure they are sealed and no sunlight can enter
  • do not use them in conjunction with binoculars or a telescope
  • meant strictly for use with your eyes
  • Concentrating sunlight with an optical aid and hoping the glasses will be enough to block the Sun’s harmful rays is taking a chance at blinding yourself
  • . If you plan on filming
  • now is the time to practice
  • Make sure well in advance of exactly what time the transit starts in your area
  • times are given on an astronomical standard – Universal Time. If you are unsure of how to convert, try the Time Zone Converter to assist you.
Mars Base

Alien Super-Earth Light Seen for 1st Time | Exoplanet Search | Space.com - 0 views

www.space.com/light-detected-55-cancrie.html

scibyte45 exoplanet Spitzer

shared by Mars Base on 09 May 12 - No Cached
  • Light from an alien "super-Earth" twice the size of our own Earth has been detected by a NASA space telescope for the first time
  • spotted light from the alien planet 55 Cancri e, which orbits a star 41 light-years from Earth
  • A year on the extrasolar planet lasts just 18 hours
  • ...27 more annotations...
  • 55 Cancri e was first discovered in 2004 and is not a habitable world
  • The world is about twice the width of Earth and is super-dense, with about eight times the mass of Earth.
  • until now, scientists have never managed to detect the infrared light from the super-Earth world.
  • pioneering the study of atmospheres of distant planets and paving the way for NASA's upcoming James Webb Space Telescope
  • Spitzer first detected infrared light from an alien planet in 2005
  • that world was "hot Jupiter," a gas giant planet much larger than 55 Cancri e that orbited extremely close to its parent star
  • other telescopes have performed similar feats
  • Spitzer's view of the 55 Cancri e is the first time the light from a rocky super-Earth type planet has been seen
  • Since the discovery of 55 Cancri e, astronomers have pinned down increasingly strange features about the planet
  • already knew it was part of an alien solar system containing five exoplanets centered on the star 55 Cancri in the constellation Cancer
  • But 55 Cancri e stood out because it is ultra-dense and orbits extremely close to its parent star
  • 26 times closer than the distance between Mercury and our own sun
  • observations revealed that the star-facing side of 55 Cancri e
  • temperatures reaching up to 3,140 degrees Fahrenheit (1,726 degrees Celsius).
  • likely a dark world that lacks the substantial atmosphere needed to warm its nighttime side
  • the planet is oozing
  • Past observations of the planet by the Spitzer Space Telescope have suggested that one-fifth of 55 Cancri e is made up of lighter elements, including water
  • the extreme temperatures and pressures on 55 Cancri e would create what scientists call a "supercritical fluid" state
  • Supercritical fluids can be imagined as a gas in a liquid state, which can occur under extreme pressures and temperatures
  • On Earth, water can become a supercritical fluid inside some steam engines.
  • This graphic illuminates the process by which astronomers using NASA's Spitzer Space Telescope have for the first time detected the light from a super-Earth planet, the alien world of 55 Cancri e 41 light-years from Earth.
  • planet is likely a rocky world covered with water in a supercritical fluid state and topped off with a steam blanket
  • could be very similar to Neptune, if you pulled Neptune in toward our sun and watched its atmosphere boil away
  • detailed in the Astrophysical Journal
  • Spitzer Space Telescope launched in 2003
  • telescope engineers modified several settings on the observatory to optimize its alien planet vision
  • conceived of Spitzer more than 40 years ago
1 - 20 of 23 Next ›
Showing 20▼ items per page