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Mars Base

AIDS vaccine candidate appears to completely clear virus from the body - 0 views

medicalxpress.com/...cine-candidate-virus-body.html

scibyte102 AIDS

shared by Mars Base on 13 Sep 13 - No Cached
  • An HIV/AIDS vaccine candidate developed by researchers at Oregon Health & Science University appears to have the ability to completely clear an AIDS-causing virus from the body
  • The promising vaccine
  • It is being tested through the use of a non-human primate form of HIV
  • ...9 more annotations...
  • simian immunodeficiency virus, or SIV, which causes AIDS in monkeys
  • it is hoped an HIV-form of the vaccine candidate can soon be tested in humans
  • approach involves the use of cytomegalovirus, or CMV, a common virus already carried by a large percentage of the population
  • the researchers discovered that pairing CMV with SIV had a unique effect
  • a modified version of CMV engineered to express SIV proteins generates and indefinitely maintains so-called "effector memory" T-cells that are capable of searching out and destroying SIV-infected cells
  • About 50 percent of monkeys given highly pathogenic SIV after being vaccinated with this vaccine became infected with SIV but over time eliminated all trace of SIV from the body
  • vaccine mobilized a T-cell response that was able to overtake the SIV invaders in 50 percent of the cases treated
  • testing suggests SIV was banished from the host
  • lab is now investigating the possible reasons why only a subset of the animals treated had a positive response in hopes that the effectiveness of the vaccine candidate can be further boosted
Mars Base

Voyager 1 Probe Captures 1st-Ever Sounds of Interstellar Space (Video) | Space.com - 0 views

www.space.com/tellar-space-sounds-video.html

scibyte102 Voyager1

shared by Mars Base on 13 Sep 13 - No Cached
  •  Voyager 1 recording of the sound of interstellar space,
  • The sounds are produced by the vibration of dense plasma, or ionized gas; they were captured by the probe's plasma wave instrument
Mars Base

At last, Voyager 1 slips into interstellar space | Atom & Cosmos | Science News - 0 views

www.sciencenews.org/..._slips_into_interstellar_space

scibyte102 Voyager1

shared by Mars Base on 13 Sep 13 - No Cached
  • the probe is surrounded by a relatively dense fog of galactic particles rather than a thin mist of solar ones
  • from the beginning
  • team hoped the probes would survive long enough to investigate the region of space where our star’s dominance finally wanes
  • ...14 more annotations...
  • more than 60,000 kilometers per hour
  • August 25, when solar particles disappeared for good
  • combined with a surge in higher-energy particles from other stars, suggested that Voyager had exited the heliosphere
  • Several well-publicized studies made that claim
  • colleagues resisted that conclusion
  • lacked evidence of what they thought would be the key signature of interstellar space: a shift in the direction of the magnetic field
  • Solar plasma produces a distinctive magnetic field because it all comes from the same source
  • scientists expected that the field would shift in interstellar space, where particles flit around in all directions
  • Not everyone agrees, including a few holdouts on the Voyager team
  • have written a paper demonstrating how plasma could become dense enough within the heliosphere to produce
  • measurement
  • many other astrophysicists say the evidence is overwhelming that Voyager 1 has crossed the heliopause, but they acknowledge that they have to determine why the magnetic field direction didn’t shift
  • NASA estimates that Voyager 1 has enough plutonium fuel to keep all its instruments powered for another seven years
  • August 25, 2012 — the same date, coincidentally, that the world lost its most famous human space explorer, Neil Armstrong
Mars Base

Voyager 1 spacecraft reaches interstellar space, study confirms - 0 views

phys.org/...ecraft-interstellar-space.html

scibyte102 Voyager1

shared by Mars Base on 13 Sep 13 - No Cached
  • University of Iowa space physicist
  • says there is solid evidence that NASA's Voyager 1 spacecraft has become the first manmade object to reach interstellar space
  • 11 billion miles distant and 36 years after it was launched
  • ...8 more annotations...
  • For several months, the relative position of Voyager 1
  • remains some lingering evidence of the nearby heliosphere beyond the heliopause.
  • April
  • there are variations in some of Voyager's measurements that may be due to the nearby presence of the heliosphere
  • 11.6 billion miles from the sun, or about 125 astronomical units.
  • it takes more than 17 hours for a radio signal to travel from the spacecraft
  • The signal strength is so incredibly weak that it takes both a 230-foot and a 110-foot-diameter antenna to receive our highest resolution data
  • moving outward from the sun at about 3.5 AU per year
Mars Base

Listen to the Sounds of Interstellar Space, Recorded by Voyager 1 - 0 views

www.universetoday.com/...ar-space-recorded-by-voyager-1

scibyte102 Voyager1

shared by Mars Base on 13 Sep 13 - No Cached
  • Voyager 1 was able to record the sounds of interstellar space. This helped the Voyager science team calculate the density of interstellar plasma
Mars Base

It's Official: Voyager 1 Is Now In Interstellar Space - 0 views

www.universetoday.com/...1-is-now-in-interstellar-space

scibyte102 Voyager1

shared by Mars Base on 13 Sep 13 - No Cached
  • NASA says the most distant human made object — the Voyager 1 spacecraft — is in interstellar space
  • It actually made the transition about a year ago
  • there is a bit of an argument on the semantics of whether Voyager 1 is still inside or outside of our Solar System
  • ...44 more annotations...
  • it is not farther out than the Oort Cloud
  • it will take 300 more years reach the Oort cloud and the spacecraft is closer to our Sun than any other star
  • the plasma environment Voyager 1 now travels through has definitely changed from what comes from our Sun to the plasma that is present in the space between stars.
  • debate
  • There’s also been a
  • between the latest various science papers and their authors
  • Scientists thought that when the spacecraft had crossed over into interstellar space, the magnetic field direction would change
  • that didn’t happen
  • scientists determined they needed to look at the properties of the plasma instead
  • The Sun’s heliosphere is filled with ionized plasma from the Sun
  • Outside that bubble, the plasma comes from the explosions of other stars millions of years ago
  • The main tell-tail difference is the interstellar plasma is denser.
  • the real instrument that was designed to make the measurements on the plasma quit working in the 1980’s
  • Instead they used the plasma wave instrument, located on the 10-meter long antennas on Voyager 1 and
  • from the Sun
  • a massive Coronal Mass Ejection
  • The antennas have radio receivers at the ends – “like the rabbit ears on old television sets
  • The CME erupted from the Sun in March 2012, and eventually arrived at Voyager 1′s location 13 months later, in April 2013
  • Because of the CME, the plasma around the spacecraft began to vibrate like a violin string
  • The pitch of the oscillations helped scientists determine the density of the plasma
  • the particular oscillations meant the spacecraft was bathed in plasma more than 40 times denser than what they had encountered in the outer layer of the heliosphere
  • The plasma wave science team reviewed its data and found an earlier, fainter set of oscillations in October and November 2012 from other CMEs
  • extrapolation of measured plasma densities from both events, the team determined Voyager 1 first entered interstellar space in August 2012
  • certainly in a new region at the edge of the solar system where things are changing rapidly
  • not yet able to say that Voyager 1 has entered interstellar space
  • the data are changing in ways that the team didn’t expect
  • after further review, the Voyager team generally accepts the August 2012 date as the date of interstellar arrival
  • The charged particle and plasma changes were what would have been expected during a crossing of the heliopause
  • expect the fields and particles science instruments on Voyager will continue to send back data through at least 2020
  • , it was first questioned in August of 2012, with more speculation in December 2012, then in March of 2013
  • Then about a month ago
  • Voyager 2, launched before Voyager 1, is the longest continuously operated spacecraft
  • emitted signals are currently very dim, at about 23 watts — the power of a refrigerator light bulb
  • Voyager mission controllers still talk to or receive data from Voyager 1 and Voyager 2 every day
  • planetary alignment that only happens every 176 years enabled the two spacecraft to join together to reach all the outer planets in a 12 year time period
  • By the time the signals get to Earth, they are a fraction of a billion-billionth of a watt
  • Data from Voyager 1′s instruments are transmitted to Earth typically at 160 bits per second
  • signal from Voyager 1 takes about 17 hours to travel to Earth.
  • After the data are transmitted to JPL and processed by the science teams, Voyager data are made publicly available
  • Scientists do not know when Voyager 1 will reach the undisturbed part of interstellar space where there is no influence from our Sun
  • They also are not certain when Voyager 2 is expected to cross into interstellar space, but they believe it is not very far behind.
  • While Voyager 1 will keep going, we will not always be able to communicate with it, as we do now
  • In 2025 all instruments will be turned off, and the science team will be able to operate the spacecraft for about 10 years after that to just get engineering data
  • In the year 40,272 AD, Voyager 1 will come within 1.7 light years of an obscure star in the constellation Ursa Minor
Mars Base

Curiosity Rolls into Intriguing 'Darwin' at 'Waypoint 1′ on Long Trek to Moun... - 1 views

www.universetoday.com/...-1-on-long-trek-to-mount-sharp

scibyte102 Curiosity

shared by Mars Base on 15 Sep 13 - No Cached
  • NASA’s Curiosity Mars rover has just rolled into an intriguing site called ‘Darwin’ at ‘Waypoint 1’
  • the long journey to Mount Sharp
  • was certain to last nearly a year
  • ...15 more annotations...
  • science team carefully choose a few stopping points for study along the way to help characterize the local terrain
  • Curiosity has arrived at Waypoint 1
  • has now driven nearly 20% of the way towards the base of the giant layered mountain
  • Altogether, the team selected five ‘Waypoints’ to investigate for a few days each
  • stay just a couple of sols at Waypoint 1 and then we hit the road again
  • Waypoint 1’ is an area of intriguing outcrops that was chosen based on high resolution orbital imagery taken by NASA’s Mars Reconnaissance Orbiter (MRO)
  • Curiosity will only stay a short time at each of the stops, the measurements collected at each ‘Waypoint’ will provide essential clues to the overall geologic and environmental history
  • scientists goal is to compare the floor of Gale Crater to the sedimentary layers of 3 mile high (5 kilometer high) Mount Sharp
  • Waypoint 1 is just over 1 mile along the approximately 5.3-mile (8.6-kilometer) route from ‘Glenelg’ to the entry point at the base of Mount Sharp
  • Curiosity spent over six months investigating the ‘Yellowknife Bay’ area inside Glenelg before departing on July 4, 2013
  • On Sept. 5, Curiosity set a new one-day distance driving record for the longest drive yet by advancing 464 feet (141.5 meters) on her 13th month
  • As Curiosity neared Waypoint 1 she stopped at a rise called ‘Panorama Point’ on Sept. 7
  • will not conduct any drilling here or at the other waypoints
  • unless there is some truly remarkable discovery
  • If all goes well Curiosity could reach the entry point to Mount Sharp sometime during Spring 2014, at her current driving pace
Mars Base

Young insect legs have real meshing gears | Zoology | Science News - 0 views

www.sciencenews.org/...t_legs_have_real_meshing_gears

scibyte102 BiologicalGear ViewerFeedback

shared by Mars Base on 15 Sep 13 - No Cached
  • Adults are bigger and heavier, Burrows says, so perhaps leg-to-leg friction syncs motions without the need for gear teeth.
Mars Base

This Insect Has The Only Mechanical Gears Ever Found in Nature | Surprising Science - 0 views

blogs.smithsonianmag.com/...cal-gears-ever-found-in-nature

scibyte102 BiologicalGear ViewerFeedback

shared by Mars Base on 16 Sep 13 - No Cached
  • To the best of our knowledge, the mechanical gear
  • evenly-sized teeth cut into two different rotating surfaces to lock them together as they turn
  • was invented sometime around 300 B.C.E. by Greek mechanics who lived in Alexandria
  • ...24 more annotations...
  • Issus coleoptratus
  • juveniles
  • have an intricate gearing system that locks their back legs together, allowing both appendages to rotate at the exact same instant, causing the tiny creatures jump forward.
  • , is believed to be the first functional gearing system ever discovered in nature
  • The finding,
  • used electron microscopes and high-speed video capture to discover the existence of the gearing and figure out its exact function.
  • To jump, both of the insect’s hind legs must push forward at the exact same time
  • The reason for the gearing, they say, is coordination
  • The researchers’ high-speed videos showed that the creatures
  • cocked their back legs in a jumping position, then pushed forward, with each moving within 30 microseconds
  • jump at speeds as high as 8.7 miles per hour
  • 30 millionths of a second
  • the skeleton is used to solve a complex problem that the brain and nervous system can’t
  • The gears are located at the top of the insects’ hind legs
  • and include 10 to 12 tapered teeth, each about 80 micrometers wide (or 80 millionths of a meter).
  • In all the Issus hoppers studied, the same number of teeth were present on each hind leg, and the gears locked together neatly
  • adults of the same insect species don’t have any gearing—as the juveniles grow up and their skin molts away
  • the adult legs are synchronized by an alternate mechanism (a series of protrusions extend from both hind legs, and push the other leg into action).
  • hypothesize that this could be explained by the fragility of the gearing
  • if one tooth breaks, it limits the effectiveness of the design
  • isn’t such a big problem for the juveniles, who repeatedly molt and grow new gears before adulthood
  • for the mature Issus, replacing the teeth would be impossible
  • There have been gear-like structures previously found on other animals
  • but they’re purely ornamental
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