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Mars Base

Why Teenagers Are So Impulsive | Science/AAAS | News - 0 views

news.sciencemag.org/...why-teenagers-are-so-impulsive

scibyte110

shared by Mars Base on 16 Nov 13 - No Cached
  • When teenagers successfully resist an urge in a common test of impulsivity, they show increased activation in a brain region associated with restraint
  • suggesting that their brains have to work harder to avoid acting on the impulse
  • Why do teens—especially adolescent males—commit crimes more frequently than adults
  • ...20 more annotations...
  • One explanation may be that as a group, teenagers react more impulsively to threatening situations than do children or adults
  • likely because their brains have to work harder to rein in their behavior
  • teenagers have a reputation for courting danger that is often attributed to immaturity or poor decision-making
  • If immaturity or lack of judgment were the only problem, however, one would expect that children, whose brains are at an even earlier stage of development
  • younger children tend to be more cautious than teenagers, suggesting that there is something unique about adolescent brain development that lures them to danger
  • It's hard to generalize about teenage impulsivity
  • some adolescents clearly have more self-control than many adults
  • a growing body of evidence suggests that, in general, teens specifically struggle to keep their cool in social situations
  • many crimes committed during adolescence involve emotionally fraught social situations
  • to test whether teens perform badly on a common impulsivity task when faced with social cues of threat
  • recruited 83 people, ranging in age from 6 to 29, to perform a simple "Go/No-Go" task
  • they watched a series of faces making neutral or threatening facial expressions flicker past on a computer screen
  • Each time the participants saw a neutral face, they were instructed to hit a button
  • They were also told to hold back from pressing the button when they saw a threatening face
  • As the participants performed the task, the researchers monitored their brain activity with functional magnetic resonance imaging.
  • teenagers made about 15% more errors than adults and children when attempting to stop themselves from pressing the button when they saw the threatening facial expression
  • Males performed worse than females, suggesting a sex difference that fits with the disproportionate number of crimes that male teens commit,
  • adolescents who did manage to restrain themselves showed significantly higher activity in a brain region called the ventromedial prefrontal cortex (vmPFC), which is involved in top-down control of behavior
  • think of it as the break
  • the teenage brain might need to work a little harder to hold that response back
Mars Base

Knee Ligament Described in 19th Century Rediscovered: Scientific American Gallery - 0 views

www.scientificamerican.com/gallery_directory.cfm

scibyte110

shared by Mars Base on 16 Nov 13 - No Cached
  • ACL tear takes about eight to 12 months to heal, and they’ve always been difficult to treat
  • Until recently, doctors were at a loss as to why patients kept complaining about instability in their knees after recovering from successful ACL-repair surgeries
  • knees would consistently fail the so-called pivot-shift test, used by physicians to evaluate sprains in the anterior and lateral parts of the knee
  • ...13 more annotations...
  • Flemish researchers has finally uncovered the problem: a previously unknown ligament in the knee
  • scientists were prompted to find the ligament after reading an article published in 1879
  • The French surgeon described a “pearly, fibrous band” and hypothesized it was an additional ligament located on the anterior part of the human knee
  • Over a century later knee surgeons and an anatomist
  • set out to determine whether the flexible connective tissue
  • exists
  • After investigating 41 unpaired knees from human cadavers the doctors found that all but one knee displayed the described ligament, now named the anterolateral ligament (ALL).
  • The discovery
  • has given basic anatomy a fresh jolt
  • hopes the study will encourage students to look to anatomy as an exciting science, where new features of the human body may be discovered
  • Other researchers, such as orthopedic surgeon
  • are currently trying to find a technique to repair that ligament
  • In the meantime they hope clinicians will take the ALL into consideration when making a diagnosis or planning reconstructive surgery.
Mars Base

Missing Piece of Long-Neck Dinosaur Finally Discovered: Scientific American - 0 views

www.scientificamerican.com/article.cfm

scibyte110 dinosaur

shared by Mars Base on 14 Nov 13 - No Cached
  • The enamel is too thin and th
  • are way too long and skinny
  • The fossil teeth were embedded in a loose boulder that had eroded out of the hillside
  • ...22 more annotations...
  • evidence that passersby were chipping away at the exposed dinosaur bones in the rock, taking souvenirs.
  • Morrison sandstone surrounding the fragile fossils was so hard that Mossbrucker and his colleagues were afraid that trying to remove the rock would irreparably damage the bone.
  • in 2011, the museum acquired some state-of-the-art pneumatic tools that can remove hard rock without transmitting damaging vibrations to fossils embedded insid
  • cheeckbone nestles against the Apatosaurus maxilla and premaxillae, the bones of the snout, and tiny specks of fish bone surround the larger assemblage
  • snout is highlighting unknown anatomical features
  • including a large
  • hollow space in the skull, which would have influenced the tone of the Apatosaur's calls
  • Other long-necks had this space
  • but A. ajax's was particularly large
  • The discovery also reveals that Lakes' long-ago excavations were close to discovering yet another Apatosaur
  • Teeth found
  • were declared by Marsh in 1884 to belong to Diplodocus lacustris, another long-neck species
  • But those teeth, now held in Yale's collections, look just like Kevin's
  • , Diplodocus lacustris didn't exist — instead, Lakes found part of Kevin and missed the rest.
  • a slew of museum volunteers are still working to coax more of Kevin from its boulder
  • The specimen got its name simply because museum staff and guests found it amusing
  • The current plan is to cleave the block in half so that the pieces can be scanned with micro-CT (computed tomography
  • s technology would allow paleontologists to see inside the block and even to 3D-print a perfect copy of the bones inside without having to remove them physically
  • don't have to put the specimen at any more risk
  • and we still get the data we need
  • The process is slow going, however, in part because the team keeps finding bones in what they expected to be just rock
  • expects to publish his findings in about a year
Mars Base

Missing Piece of Long-Neck Dinosaur Finally Discovered: Scientific American - 0 views

www.scientificamerican.com/article.cfm

scibyte110 dinosaur

shared by Mars Base on 14 Nov 13 - No Cached
  • A small roadside quarry west of Denver
  • , has revealed a new treasure: the snout of the long-necked dinosaur Apatosaurus ajax
  • The specimen, nicknamed Kevin, is the first Apatosaurus ajax muzzle ever found
  • ...6 more annotations...
  • the discovery is likely to help paleontologists understand how A. ajax is related to other Apatosaurus
  • volunteers have been painstakingly carving Kevin's bones out of sandstone for two years
  • Apatosaurus is perhaps most notorious for its complicated naming history
  • Another paleontologist, Elmer Riggs, killed the Brontosaurus genus in 1903 after noting that the skeletons didn't vary enough to justify two genuses
  • A. ajax was as long as three school busses and weighed as much as eight Asian elephants
  • Apatosaurus had lightweight vertebrae that would have allowed it to move its head rapidly: Imagine a neck the length of a school bus, flitting up and down and side to side like an ostrich neck
Mars Base

Soyuz Lands Safely with Space Station Crew and Olympic Torch - 0 views

www.universetoday.com/...station-crew-and-olympic-torch

scibyte109 Olympics

shared by Mars Base on 11 Nov 13 - No Cached
  • Expedition 37 crew members Karen Nyberg of NASA, Fyodor Yurchikhin of the Russian Federal Space Agency and Luca Parmitano of the European Space Agency have returned to Earth from the International Space Station
  • after spending 166 days in space.
Mars Base

Just a few years of early musical training benefits the brain later in life - 0 views

medicalxpress.com/...ly-musical-benefits-brain.html

scibyte109

shared by Mars Base on 07 Nov 13 - No Cached
  • Older adults who took music lessons as children but haven't actively played an instrument in decades have a faster brain response to a speech sound than individuals who never played an instrument,
  • As people grow older, they often experience changes in the brain that compromise hearing
  • the brains of older adults show a slower response to fast-changing sounds, which is important for interpreting speec
  • ...10 more annotations...
  • recent studies of musicians suggest lifelong musical training may offset these and other cognitive declines
  • previous studies show such age-related declines are not inevitable
  • the current study,
  • explored whether limited musical training early in life is associated with changes in the way the brain responds to sound decades later
  • t the more years study participants spent playing instruments as youth, the faster their brains responded to a speech sound.
  • For the study, 44 healthy adults, ages 55-76, listened to a synthesized speech syllable ("da") while researchers measured electrical activity in the auditory brainstem
  • This region of the brain processes sound and is a hub for cognitive, sensory, and reward information
  • researchers discovered that, despite none of the study participants having played an instrument in nearly 40 years
  • participants who completed 4-14 years of music training early in life had the fastest response to the speech sound (on the order of a millisecond faster than those without music training).
  • a millisecond faster may not seem like much, but the brain is very sensitive to timing and a millisecond compounded over millions of neurons can make a real difference
Mars Base

Mars Science Laboratory: Curiosity Performs Warm Reset - 0 views

mars.jpl.nasa.gov/...index.cfm

scibyte109 Curiosity

shared by Mars Base on 11 Nov 13 - No Cached
  • NASA's Mars rover Curiosity experienced an unexpected software reboot (also known as a warm reset)
  • (11/7/13
  • during a communications pass as it was sending engineering and science data to the Mars Reconnaissance Orbiter, for later downlinking to Earth
  • ...5 more annotations...
  • occurred about four-and-half hours after new flight software had been temporarily loaded into the rover's memory
  • At the time the event occurred, Curiosity was in the middle of a scheduled, week-long flight software update and checkout activity
  • A warm reset is executed by flight software when it identifies a problem with one of its operations
  • The reset restarts the flight software into its initial state. Since the reset, the rover has been performing operations and communications as expected
  • This is the first time that Curiosity has executed a fault-related warm reset during its 16-plus months of Mars surface operations.
Mars Base

Astronomers answer key question: How common are habitable planets? - 0 views

phys.org/...-common-habitable-planets.html

scibyte109

shared by Mars Base on 07 Nov 13 - No Cached
  • astronomers analyzed all four years of Kepler data in search of Earth-size planets in the habitable zones of sun-like stars
  • Based on this analysis, they estimate that 22 percent of stars like the sun have potentially habitable Earth-size planets, though not all may be rocky or have liquid water
  • NASA's Kepler spacecraft
  • ...22 more annotations...
  • provided enough data to complete its mission objective: to determine how many of the 100 billion stars in our galaxy have potentially habitable planets
  • Based on a statistical analysis
  • astronomers now estimate that one in five stars like the sun have planets about the size of Earth and a surface temperature conducive to life.
  • nearly 20 years since the discovery of the first extrasolar planet around a normal star
  • Since then we have learned that most stars have planets of some size and that Earth-size planets are relatively common in close-in orbits that are too hot for life
  • Earth-size planets in Earth-size orbits are not necessarily hospitable to life, even if they orbit in the habitable zone of a star where the temperature is not too hot and not too cold
  • thick atmospheres, making it so hot at the surface that DNA-like molecules would not survive
  • rocky surfaces that could harbor liquid water suitable for living organisms
  • Last week,
  • provided hope that many such planets actually are rocky
  • NASA launched the Kepler space telescope in 2009 to look for planets that cross in front of, or transit, their stars, which causes a slight diminution – about one hundredth of one percent – in the star's brightness
  • 150,000 stars photographed every 30 minutes for four years
  • reported more than 3,000 planet candidates
  • the Keck Telescopes in Hawaii
  • help them determine each star's true brightness and calculate the diameter of each transiting planet, with an emphasis on Earth-diameter planets.
  • The team's definition of habitable is that a planet receives between four times and one-quarter the amount of light that Earth receives from the sun
  • Independently
  • focused on the 42,000 stars that are like the sun or slightly cooler and smaller, and found 603 candidate planets orbiting them
  • Only 10 of these were Earth-size, that is, one to two times the diameter of Earth and orbiting their star at a distance where they are heated to lukewarm temperatures suitable for life
  • Accounting for missed planets, as well as the fact that only a small fraction of planets are oriented so that they cross in front of their host star as seen from Earth, allowed them to estimate that 22 percent of all sun-like stars in the galaxy have Earth-size planets in their habitable zones.
  • All of the potentially habitable planets found in their survey are around K stars, which are cooler and slightly smaller than the sun
  • analysis shows that the result for K stars can be extrapolated to G stars like the sun
Mars Base

An artificial blood substitute from Transylvania - 0 views

medicalxpress.com/...d-substitute-transylvania.html

scibyte109

shared by Mars Base on 07 Nov 13 - No Cached
  • Researchers in
  • Romania, have recently made some significant advances in developing artificial blood substitutes
  • formulation is based not on synthetic hemoglobins, but rather on hemerythrin protein extracted from marine worms
  • ...12 more annotations...
  • the team has been testing their blood substitute in both mice and in cultured cells
  • initial results suggest that many of the adverse effects normally associated with either perfluorocarbon (PFC) or hemoglobin-based oxygen carrier (HBOC) substitutes can be eliminated, or at least minimized
  • Human blood only has a shelf life of a few weeks
  • It also needs to be matched to the recipient's blood type,
  • the risks of disease transmission can be minimized by testing, dangers still present if the donor has been recently infected
  • What makes hemoglobin such a success, is a phenomenon known as cooperative binding
  • as more oxygen binds to hemoglobin in the lungs, it becomes even easier for additional oxygen to bind
  • The problem
  • is that one way or another, the hemoglobin they contain ends up escaping and causing serious damage to organs like the kidneys
  • While their small size allows them to penetrate and oxygenate the nooks and crannies of the body much better than RBCs, that same feature also leads to undesireable extravasation into tissue
  • The goal is not to develop a permanent replacement solution, but rather something that could be used to bridge a critical situation for the few hours or days
  • Researchers have found when these modified hemoglobins do get into tissues, they bind nitric oxide, which appears to have the result that the patient's blood pressure rises precipitously
Mars Base

Rare New Species of Carolina Hammerhead Shark Discovered - 0 views

www.scienceworldreport.com/...ammerhead-shark-discovered.htm

scibyte109 ViewerFeedback sharks

shared by Mars Base on 10 Nov 13 - No Cached
  • The Carolina hammerhead has long eluded discovery due to the fact that it is outwardly indistinguishable from the common scalloped hammerhead
  • The new species, named Sphyrna gilberti, was actually discovered as scientists were looking for more common hammerheads.
  • Scientists have now announced that they've discovered a new species of rare shark, the Carolina hammerhead
  • ...5 more annotations...
  • South Carolina is a well-known pupping ground for several species of sharks, which means that researchers were collecting samples there for study
  • The scalloped hammerheads that they were collecting had two different genetic signatures in both the mitochondrial and nuclear genomes
  • the scientists found that the anomalous scalloped hammerhead had been described in 1967 and had 10 fewer vertebrae than the normal scalloped hammerhead. Intrigued
  • In the end, the scientists found that there was genetic evidence to show that this hammerhead was, in fact, a new species.
  • scientists aren't sure exactly how many individuals still exist in the wild
Mars Base

New 'Walking' Shark Species Caught on Video | LiveScience - 0 views

www.livescience.com/new-walking-shark-species.html

scibyte109 ViewerFeedback sharks

shared by Mars Base on 10 Nov 13 - No Cached
  • A new species of "walking" shark has been discovered in a reef off a remote Indonesian island
  • These sharks don't always rely on "walking" to move about — often, they only appear to touch the seafloor as they swim using their pectoral and pelvic fins in a walklike gait
  • The shark grows up to 27 inches (70 centimeters) long and is harmless to humans
  • ...5 more annotations...
  • Hemiscyllium halmahera, named after the eastern Indonesian island of Halmahera where it was found
  • Of all known
  • walking sharks, six of nine species hail from Indonesia
  • The animals lay eggs under coral ledges, after which the young sharks lead relatively sedentary lives until adulthood
  • These sharks do not cross areas of deep water and are found in isolated reefs
Mars Base

Russia launches Sochi Olympic torch into space - 0 views

phys.org/...sochi-olympic-torch-space.html

scibyte109 Olympics

shared by Mars Base on 07 Nov 13 - No Cached
  • Russian officials have made it clear that the torch will remain unlit at all times for safety reasons.
  • the Olympic torch was carried into space ahead of the 1996 and 2000 Olympics in Atlanta and Sydney but has never before been taken on a spacewalk
Mars Base

Crew Launches to Space Station with Olympic Torch - 0 views

www.universetoday.com/...ace-station-with-olympic-torch

scibyte109 Olympics

shared by Mars Base on 07 Nov 13 - No Cached
  • In an usual situation, when the new crew arrives, there will be nine crew members and three Soyuz vehicles at the ISS
  • The new crew is bringing the unlit torch along, then
  • the space station’s current crew, will take the torch out on a spacewalk,
  • ...6 more annotations...
  • The real reason for the spacewalk is to do some routine Russian maintenance outside the station
  • Then,
  • three crew members will return
  • and they will bring the torch back home
  • The torch then will be given back to Olympic officials and it will be used in the opening ceremonies of the February games
  • There have not been nine crew members on the ISS since 2009.
Mars Base

Indian Mars mission on track, makes first engine burns - 0 views

phys.org/...indian-mars-mission-track.html

scibyte109 SpacecraftUpdate India-MarsOrbiterMission

shared by Mars Base on 08 Nov 13 - No Cached
  • The main aim of the mission is to detect methane in the Martian atmosphere, which could provide evidence of some sort of life form
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