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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

Faraway moon or faint star? Possible exomoon found - 0 views

phys.org/...y-moon-faint-star-exomoon.html

scibyte126 exoplanets

shared by Mars Base on 11 Apr 14 - No Cached
  • NASA-funded researchers have spotted the first signs of an "exomoon," and though they say it's impossible to confirm its presence
  • The discovery was made by watching a chance encounter of objects in our galaxy, which can be witnessed only once
  • won't have a chance to observe the exomoon candidate again
  • ...29 more annotations...
  • can expect more unexpected finds like this.
  • international study
  • using telescopes
  • technique, called gravitational microlensing, takes advantage of chance alignments between stars
  • When a foreground star passes between us and a more distant star, the closer star can act like a magnifying glass to focus and brighten the light of the more distant one
  • These brightening events usually last about a month
  • If the foreground star—or what astronomers refer to as the lens—has a planet circling around it, the planet will act as a second lens to brighten or dim the light even more
  • carefully scrutinizing these brightening events, astronomers can figure out the mass of the foreground star relative to its planet.
  • the foreground object could be a free-floating planet, not a star
  • astronomers are actively looking for exomoons—for example, using data from NASA's Kepler mission - so far, they have not found any.
  • In the new study, the nature of the foreground, lensing object is not clear. The ratio of the larger body to its smaller companion is 2,000 to 1.
  • That means the pair could be either a small, faint star circled by a planet about 18 times the mass of Earth—or a planet more massive than Jupiter coupled with a moon weighing less than Earth.
  • astronomers have no way of telling which of these two scenarios is correct
  • One possibility is for the lensing system to be a planet and its moon
  • The answer to the mystery lies in learning the distance to the circling duo
  • A lower-mass pair closer to Earth will produce the same kind of brightening event as a more massive pair located farther away
  • once a brightening event is over, it's very difficult to take additional measurements of the lensing system and determine the distance
  • The true identity of the exomoon candidate and its companion, a system dubbed MOA-2011-BLG-262, will remain unknown
  • In the future, however, it may be possible to obtain these distance measurements during lensing events
  • NASA's Spitzer and Kepler space telescopes, both of which revolve around the sun in Earth-trailing orbits, are far enough away from Earth to be great tools for the parallax-distance technique.
  • The basic principle of parallax can be explained by holding your finger out, closing one eye after the other, and watching your finger jump back and forth
  • A distant star, when viewed from two telescopes spaced really far apart, will also appear to move
  • When combined with a lensing event, the parallax effect alters how a telescope will view the resulting magnification of starlight
  • Though the technique works best using one telescope on Earth and one in space, such as Spitzer or Kepler, two ground-based telescopes on different sides of our planet can also be used
  • Meanwhile, surveys
  • are turning up more and more planets
  • These microlensing surveys have discovered dozens of exoplanets so far, in orbit around stars and free-floating
  • A previous NASA-funded study, also led by the MOA team, was the first to find strong evidence for planets the size of Jupiter roaming alone in space, presumably after they were kicked out of forming planetary systems
  • The new exomoon candidate, if real, would orbit one such free-floating planet.
Mars Base

Failed Space Station Computer Spurs Contingency Spacewalk Plans - 0 views

www.universetoday.com/...rs-contingency-spacewalk-plans

scibyte126 iss

shared by Mars Base on 13 Apr 14 - No Cached
  • April 12
  • NASA is preparing a contingency spacewalk to deal with a broken backup computer component
  • in an update Saturday (April 12)
  • ...2 more annotations...
  • there’s no timeline yet for the spacewalk, the agency must consider carefully when to do it given a cargo ship is supposed to arrive at station on Wednesday.
  • The failure was uncovered Friday “during a routine health check” of a box called EXT-2, which backs up a primary component that sits outside on the S0 truss (near the station’s center)
Mars Base

Contingency Spacewalk Planned Next Week, But Dragon Must Arrive At Space Station First - 0 views

www.universetoday.com/...-arrive-at-space-station-first

scibyte126 iss

shared by Mars Base on 14 Apr 14 - No Cached
  • : a quick 2.5-hour run to swap out a failed backup computer that controls several systems
  • including robotics
  • t NASA doesn’t want to go ahead with it until spare spacesuit parts arrive, in the aftermath of a life-threatening suit leak that took place last summer.
  • ...14 more annotations...
  • Those parts are on board the
  • SpaceX Dragon spacecraft
  • The spacewalk would take place April 22 — if Dragon gets there as planned on Wednesday
  • e Dragon is carrying a new spacesuit, components to fix an existing spacesuit, critical research experiments and food for the six crew members of Expedition 39.
  • The challenge, however, is making sure the station could be ready even if the primary multiplexer demultiplexer (MDM) fails before spacewalkers can make the backup replacement.
  • There are more than a dozen MDMs on station, but each one controls different functions
  • This primary MDM not only controls a robotics mobile transporter, but also radiators and a joint to move the station’s solar arrays, among other things.
  • . NASA needs to reposition the arrays when a vehicle approaches because plumes from the thrusters can put extra “loads” or electrical power on the system.
  • Luckily, the angle of the sun is such these days that the array can sit in the same spot for a while, at least two to three weeks
  •  NASA configured the station so that even if the primary computer fails, the array will automatically position correctly
  • NASA also will move a mobile transporter on station today so that the station’s robotic arm is ready to grasp the Dragon when it arrives, meaning that even if the primary computer fails the transporter will be in the right spot
  • If Dragon is delayed again, the next launch opportunity is April 18 and the spacewalk would be pushed back
  • There are at least two or three spare MDMs on station
  • the one needed for this particular spacewalk is inside the U.S. Destiny laboratory, which is handily right next to the S0 truss and spacesuit worksite.
Mars Base

A Tetrad of Lunar Eclipses - NASA Science - 0 views

science.nasa.gov/...27mar_tetrad

scibyte126 moon ViewerFeedback

shared by Mars Base on 12 Apr 14 - No Cached
  • For people in the United States, an extraordinary series of lunar eclipses is about to begin.
  • a lunar eclipse tetrad—a series of 4 consecutive total eclipses occurring at approximately six month intervals
  • The total eclipse of April 15, 2014, will be followed by another on Oct. 8, 2014, and another on April 4, 2015, and another on Sept. 28 2015.
  • ...16 more annotations...
  • The most unique thing about the 2014-2015 tetrad is that all of them are visible for all or parts of the USA
  • On average, lunar eclipses occur about twice a year, but not all of them are total.  There are three types
  • A penumbral eclipse is when the Moon passes through the pale outskirts of Earth’s shadow.  It’s so subtle, sky watchers often don’t notice an eclipse is underway
  • A partial eclipse is more dramatic.  The Moon dips into the core of Earth’s shadow, but not all the way, so only a fraction of Moon is darkened.
  • A total eclipse, when the entire Moon is shadowed, is best of all.  The face of the Moon turns sunset-red for up to an hour or more as the eclipse slowly unfolds.
  • Usually, lunar eclipses come in no particular order
  • Occasionally, though, the sequence is more orderly. When four consecutive lunar eclipses are all total, the series is called a tetrad.
  • During the 21st century, there are 9 sets of tetrads
  • a frequent occurrence in the current pattern of lunar eclipses
  • During the three hundred year interval from 1600 to 1900, for instance, there were no tetrads at all
  • Why red?
  • Imagine yourself standing on a dusty lunar plain looking up at the sky. Overhead hangs Earth
  • nightside down, completely hiding the sun behind it. The eclipse is underway
  • As you scan your eye around Earth's circumference, you're seeing every sunrise and every sunset in the world, all of them, all at once
  • This incredible light beams into the heart of Earth's shadow, filling it with a coppery glow and transforming the Moon into a great red orb.
  • More information about the lunar eclipse may be found on NASA's eclipse home page
Mars Base

Large Hadron Collider team announces beginning of restart - 0 views

phys.org/...ron-collider-team-restart.html

scibyte126 LargeHadronCollider

shared by Mars Base on 09 Apr 14 - No Cached
  • scientists working at CERN's Large Hadron Collider (LHC) facility has reported
  • that the process of restarting the massive experimental mechanism has begun
  • though it won't finish until sometime next year
  • ...12 more annotations...
  • will have to be restarted in pieces to ensure that each is operating properly before the next can be brought online
  • the facility is in the process of an upgrade, which has been in the planning stages for several years and will include upgrades to several pieces and parts of the facility that support the LHC as well as the main accelerator itself
  • The team recognized that the facility had begun to suffer from diminishing returns
  • many parts could be improved due to the development of new technology and improvements on old ways of doing things.
  • the team has successfully restarted the part they call the source—the piece of equipment responsible for stripping electrons off of hydrogen atoms for use in producing protons.
  • Next up the team plans to fire up Linac2, an accelerator whose job it is to give protons their initial push
  • After that a booster will be started that will be used to push the protons even faster
  • For the LHC to be used in its proper context, it must receive protons that are already moving exceedingly fast.
  • Team members have made much of the complete upgrade to the control system
  • that integrates all of the systems and which of course will be central to a successful reboot.
  • In addition to swapping out parts for new and improved technology, technicians will also be replacing worn cables or other minor but necessary components
  • If all goes well, the LHC should be ready and back in business sometime early next year.
Mars Base

April 22 - Today in Science History - Scientists born on April 22nd, died, and events - 0 views

www.todayinsci.com/...4_22.htm

scibyte126 LookingBackApr

shared by Mars Base on 12 Apr 14 - No Cached
  • Surgery book
  • In 1575, printing of Ambroise Paré's book Oeuvres Complètes (Complete Works) was finished, but its publication was opposed by establishment physicians. His previous texts on surgery had popularized a new way to treat gunshot wounds without cauterisation, reintroduced the ligature in amputation, and improved midwifery techniques. These many writings were gathered together in this one new volume, which spread his teachings throughout the world. It remained in print for a century and ran to thirteen editions. He wrote in French instead of Latin with practical, common sense so that many barber-surgeons, who (like Paré) were unable to interpret Latin, had access to medical knowledge otherwise unavailable from Latin texts
Mars Base

April 19 - Today in Science History - Scientists born on April 19th, died, and events - 0 views

www.todayinsci.com/...4_19.htm

scibyte126 LookingBackApr

shared by Mars Base on 12 Apr 14 - No Cached
  •  Indian satellite
  • In 1975, the first satellite built in India was launched from Volgograd Launch Station, Russia, on a Soviet Intercosmos C-1 rocket. It was named Aryabhata, after a noted 5th-century Indian mathematician. The 360-kg satellite had been built during 20 months by the Indian Space Research Organization (ISRO) in Peenya, Bangalore, by a team led by Prof. U. R. Rao. Its shape was a 26-sided polygon, 1.4-m diam., with all faces covered in solar cells, except the top and bottom. It was designed to carry out experiments in X-ray astronomy, aeronomics, and solar physics, communicating with a 46-watt VHF transmitter. However, after only 4 days in orbit, a power failure ended any further experiments. It remained in orbit nearly 17 years, until it reentered the Earth's atmosphere on 11 Feb 1992
Mars Base

April 16 - Today in Science History - Scientists born on April 16th, died, and events - 0 views

www.todayinsci.com/...4_16.htm

scibyte126 LookingBackApr

shared by Mars Base on 12 Apr 14 - No Cached
  •  First woman to fly across English Channel
  • In 1912, American aviator Harriet Quimby became the first female pilot to fly across the English Channel. She left England in a 50-hp monoplane lent to her by Louis Blériot. She headed for France in a plane she had never flown before and a compass she had just learned how to use. Despite poor visibility and fog, Quimby landed 59 minutes later near Hardelot, France. Upon landing, she was greeted by the local residents, but the Titanic sinking just days earlier, limited reporting of Quimby's achievement in the world press. She died the same year, on 1 Jul 1912, when she lost control of her plane at a flying exhibition near Quincy, Mass. She was the first American woman to become a licensed pilot, but her career as a pilot lasted a mere 11 months.
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