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Mars Base

Cholesterol-lowering eye drops could treat macular degeneration - 0 views

medicalxpress.com/...s-atherosclerosis-macular.html

scibyte89

shared by Mars Base on 03 Apr 13 - No Cached
  • A new study raises the intriguing possibility that drugs prescribed to lower cholesterol may be effective against macular degeneration, a blinding eye disease.
  • Researchers
  • have found that age-related macular degeneration, the leading cause of vision loss in Americans over 50, shares a common link with atherosclerosis
  • ...25 more annotations...
  • Both problems have the same underlying defect: the inability to remove a buildup of fat and cholesterol
  • researchers shed new light on how deposits of cholesterol contribute to macular degeneration and atherosclerosis and even blood vessel growth in some types of cancer
  • Patients who have atherosclerosis often are prescribed medications to lower cholesterol and keep arteries clear
  • This study suggests that some of those same drugs could be evaluated in patients with macular degeneration
  • we need to investigate whether vision loss caused by macular degeneration could be prevented with cholesterol-lowering eye drops or other medications that might prevent the buildup of lipids beneath the retina
  • The new research centers on macrophages, key immune cells that remove cholesterol and fats from tissues
  • In macular degeneration, the excessive buildup of cholesterol begins to occur as we age, and our macrophages begin to malfunction
  • In the "dry" form of age-related macular degeneration, doctors examining the eye can see lipid deposits beneath the retina
  • As those deposits become larger and more numerous, they slowly begin to destroy the central part of the eye, interfering with the vision needed to read a book or drive a car
  • As aging macrophages clear fewer fat deposits beneath the retina, the macrophage cells themselves can become bloated with cholesterol, creating an inflammatory process that leads to the formation of new blood vessels that can cause further damage
  • Those vessels characterize the later "wet" form of the disease
  • that inflammation creates a toxic mix of things that leads to new blood vessel growth
  • Most of the vision loss
  • is the result of bleeding and scar-tissue formation related to abnormal vessel growth
  • the scientists identified a protein that macrophages need to clear fats and cholesterol
  • As mice and humans age, they make less of the protein, and macrophages become less effective at engulfing and removing fat and cholesterol
  • team found that macrophages, from old mice and in patients with macular degeneration, have inadequate levels of the protein, called ABCA1, which transports cholesterol out of cells
  • As a result, the old macrophages accumulated high levels of cholesterol and couldn't inhibit the growth of the damaging blood vessels
  • when the researchers treated the macrophages with a substance that helped restore levels of ABCA1, the cells could remove cholesterol more effectively, and the development of new blood vessels was slowed
  • able to deliver the drug, called an LXR agonist, in eye drops
  • found that we could reverse the macular degeneration in the eye of an old mouse
  • could focus therapy only on the eyes, and we likely could limit the side effects of drugs taken orally
  • since macrophages are important in atherosclerosis and in the formation of new blood vessels around certain types of cancerous tumors, the same pathway also might provide a target for more effective therapies for those diseases
  • can reverse the disease cascade in mice by improving macrophage function, either with eye drops or with systemic treatments,
  • Some of the therapies already being used to treat atherosclerosis target this same pathway, so we may be able to modify drugs that already are available and use them to deliver treatment to the eye
Mars Base

Astronomers Watch as a Black Hole Eats a Rogue Planet - 0 views

www.universetoday.com/...black-hole-eats-a-rogue-planet

scibyte89 BlackHole

shared by Mars Base on 03 Apr 13 - No Cached
  • Astronomers using the Integral space observatory were able to watch as the planet was eaten by a black hole that had been inactive for decades
  • The observation was
  • from a galaxy that has been quiet for at least 20–30 years
  • ...14 more annotations...
  • the event is a preview of a similar feeding event that is expected to take place with the black hole at the center of our own Milky Way Galaxy
  • galaxy NGC 4845, 47 million light-years away
  • Astronomers were using Integral to study a different galaxy when they noticed a bright X-ray flare coming from another location in the same wide field-of-view
  • the origin was confirmed as NGC 4845, a galaxy never before detected at high energies
  • the emission was traced from its maximum in January 2011, when the galaxy brightened by a factor of a thousand, and then as it subsided over the course of the year
  • By analyzing the characteristics of the flare, the astronomers could determine that the emission came from a halo of material around the galaxy’s central black hole as it tore apart and fed on an object of 14–30 Jupiter masses, and so the astronomers say the object was either a super-Jupiter or a brown dwarf
  • This object appears to have been ‘wandering,’ which would fit the description of recent studies
  • The black hole in the center of NGC 4845 is estimated to have a mass of around 300,000 times that of our own Sun
  • This is the first time where we have seen the disruption of a substellar object by a black hole
  • estimate that only its external layers were eaten by the black hole, amounting to about 10% of the object’s total mass, and that a denser core has been left orbiting the black hole
  • The flaring event in NGC 4845 might be similar to what is expected to happen with the supermassive black hole at the center of our own Milky Way Galaxy
  • these events will tell astronomers more about what happens to the demise of different types of objects as they encounter black holes of varying sizes
  • Estimates are that events like these may be detectable every few years in galaxies around us
  • the emission brightened and decayed shows there was a delay of 2–3 months between the object being disrupted and the heating of the debris in the vicinity of the black hole.
Mars Base

Could scientists peek into your dreams? (w/ video) - 0 views

medicalxpress.com/...2013-04-scientists-peek.html

scibyte89 Dreams

shared by Mars Base on 05 Apr 13 - No Cached
  • small new study suggests
  • Visual experiences you have when dreaming are detectable by the same type of brain activity that occurs when looking at actual images when you're awake
  • The scientists created decoding computer programs based on brain activity measured while wide-awake study participants looked at certain images
  • ...16 more annotations...
  • right after being awakened from the early stages of sleep, the researchers asked the subjects to describe the dream they were having
  • used functional MRI to monitor brain activity of the participants and polysomnography to record the physical changes that occur during sleep
  • compared evidence of brain activity when participants were awake and looking at real images to the brain activity they saw when participants were dreaming
  • the study shows it may be possible to use brain activity patterns to understand something about what a person is dreaming about
  • current approach requires the data of image viewing and sleep within the same [person
  • methods being developed for aligning brain patterns across people
  • there are practical applications to the research
  • evidence suggesting that the pattern of spontaneous brain activity is relevant to health issues
  • researchers chose to awaken the subjects in light sleep rather than in deeper "rapid eye movement" (REM) sleep solely to make the research easier to do
  • it takes at least an hour to reach first REM stage, it would be difficult to get sleep and dream data from multiple participants
  • why it is so hard to remember a dream minutes after waking up
  • thinks it is because particular neurotransmitters or brain regions involved in memory are not active during sleep
  • During sleep and dreaming, part of the brain—the higher visual cortex—is working as if seeing images
  • one expert said the results are intriguing, he was cautious
  • previous disappointments relating brain activity to complex visual experience
  • like to see this replicated
Mars Base

Dream contents deciphered by computer | Body & Brain | Science News - 0 views

www.sciencenews.org/...ontents_deciphered_by_computer

scibyte89 Dreams

shared by Mars Base on 05 Apr 13 - No Cached
  • Experiments with mice have revealed aspects of sleep and dreaming, such as how the experiences contribute to forming memories
  • researchers recorded brain activity in three adult male volunteers during the early stages of sleep
  • After the subjects had dozed off, they were repeatedly awakened and asked for detailed reports on what they had seen while sleeping
  • ...6 more annotations...
  • After gathering at least 200 such reports from the three men, the researchers used a lexical database to group the dreamed objects in coarse categories, such as street, furniture and girl
  • On average, the computer could pick which of two objects had appeared in a dream 70 percent of the time
  • Computer algorithms sorted through
  • patterns of brain activity, linking particular patterns with objects
  • The study bolsters the notion that the vivid imagery of dreams, no matter how fantastic, is as real as waking life,
  • from the brain’s perspective
Mars Base

Hydrogen Peroxide Could Feed Life on Europa - 0 views

www.universetoday.com/...xide-could-feed-life-on-europa

scibyte89 Europa

shared by Mars Base on 06 Apr 13 - No Cached
  • According to research
  • Jupiter’s ice-encrusted moon Europa has hydrogen peroxide across much of the surface of its leading hemisphere
  • compound
  • ...11 more annotations...
  • could potentially provide energy for life if it has found its way into the moon’s subsurface ocean.
  • The availability of oxidants like peroxide on Earth was a critical part of the rise of complex, multicellular life
  • The highest concentration of peroxide found was on the side of Europa that always leads in its orbit around Jupiter,
  • roughly 20 times more diluted than the hydrogen peroxide mixture available at drug stores
  • The concentration
  • then drops off to nearly zero on the hemisphere of Europa that faces backward in its orbit.
  • Hydrogen peroxide was first detected on Europa by NASA’s Galileo mission, which explored the Jupiter system from 1995 to 2003
  • Galileo observations were of a limited region. The new Keck data show that peroxide is widespread across much of the surface of Europa, and the highest concentrations are reached in regions where Europa’s ice is nearly pure water with very little sulfur contamination
  • scientists think hydrogen peroxide is an important factor for the habitability of the global liquid water ocean under Europa’s icy crust
  • hydrogen peroxide decays to oxygen when mixed into liquid water
  • abundant compounds like peroxide could help to satisfy the chemical energy requirement needed for life within the ocean, if the peroxide is mixed into the ocean
Mars Base

Will the Europa Clipper Cruise to Jupiter's Moon? : Discovery News - 0 views

news.discovery.com/...-to-the-jovian-moon-130401.htm

scibyte89 Europa

shared by Mars Base on 09 Apr 13 - No Cached
  • a resolution
  • was recently passed by the House and Senate outlining the extent of government funding
  • “$75,000,000 shall be for pre-formulation and/or formulation activities for a mission that meets the science goals outlined for the Jupiter Europa mission
  • ...7 more annotations...
  • Europa recently hit the headlines after planetary scientists
  • uncovered the presence of magnesium sulfate salt — a.k.a. Epsom salt — on Europa’s surface
  • the presence of magnesium sulfate is suggestive of a cycling of Europa’s salty ocean with the surface.
  • Although this is good news, it’s also a reminder that potentially habitable moons don’t only orbit Jupiter
  • Enceladus
  • the Saturnian moon
  • is known to possess salty liquid water beneath its surface, plus an internal heat source, that generates Enceladus’ famous geysers
Mars Base

Breakthrough cancer-killing treatment has no side-effects, study finds - 0 views

medicalxpress.com/...ng-treatment-side-effects.html

scibyte89 scibyte90 Cancer

shared by Mars Base on 07 Apr 13 - No Cached
  • Cancer cells grow faster than normal cells and in the process absorb more materials than normal cells
  • took advantage of that fact by getting cancer cells to take in and store a boron chemical
  • When those boron-infused cancer cells were exposed to neutrons, a subatomic particle, the boron atom shattered and selectively tore apart the cancer cells, sparing neighboring healthy cells
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  • The technique worked excellently in mice
  • ready to move on to trials in larger animals, then people
  • This innovative treatment produced none of the harmful side-effects of conventional chemo and radiation cancer therapies.
  • A particular form of boron will split when it captures a neutron and release lithium, helium and energy
  • the helium and lithium atoms penetrate the cancer cell and destroy it from the inside without harming the surrounding tissues.
Mars Base

Regaining proper hearing at last - 0 views

medicalxpress.com/...2013-04-regaining-proper.html

scibyte89 Hearing

shared by Mars Base on 08 Apr 13 - No Cached
  • In the case of patients with severe hearing impairments, however, conventional behind-the-ear hearing aids reach the limits of their usefulness
  • These patients' hearing can only be helped by an implant, which amplifies sounds more effectively than conventional systems and boasts better sound quality
  • these middle ear implants require complex operations that last several hours. The high risk and expense of the surgery mean that it is rarely performed
  • ...13 more annotations...
  • The new solution is composed of three parts: a case with a microphone and battery; wireless, optical signal and energy transmission between the outer and middle ear; and an electro-acoustic transducer – the centerpiece and loudspeaker of the implant.
  • Researchers
  • are developing the electro-acoustic transducer, which will be round in shape and measure approximately 1.2 millimeters
  • To implant our system, all surgeons have to do is make a small incision at the side of the eardrum and then fold it forward. This can be done in outpatient surgery."
  • takes the form of a piezoelectric micro-actuator, is then placed directly at the connection between the middle and inner ear known as the "round window"
  • there it transmits acoustic signals to the inner ear in the form of amplified mechanical vibrations, thereby enhancing the hearing capacity of patients
  • it can output volumes of up to 120 decibels, which is roughly the noise a jackhammer makes.
  • This high performance is necessary for very good speech comprehension, particularly for high-pitched sounds, which people who are severely hard of hearing find especially difficult to pick up
  • currently testing a first working prototype in the laboratory. Results have been positive to date
  • The individual components of the hearing aid have all been developed. The next step is to optimize and assemble them
  • The implant must measure up to high requirements: the material must be encased so the body tolerates it and it has to remain stable over long periods
  • hearing aid implants should last at least ten years
  • optimized individual components should be ready by June of this year; testing of the overall system is planned for 2014
Mars Base

Mars Science Laboratory: Remaining Martian Atmosphere Still Dynamic - 0 views

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

scibyte89 Curiosity

shared by Mars Base on 09 Apr 13 - No Cached
  • Evidence has strengthened this month that Mars lost much of its original atmosphere by a process of gas escaping from the top of the atmosphere
  • Curiosity's Sample Analysis at Mars (SAM) instrument analyzed an atmosphere sample
  • using a process that concentrates selected gases
  • ...17 more annotations...
  • The results provided the most precise measurements ever made of isotopes of argon in the Martian atmosphere
  • found
  • the clearest and most robust signature of atmospheric loss on Mars
  • Isotopes are variants of the same element with different atomic weights
  • SAM found that the Martian atmosphere has about four times as much of a lighter stable isotope (argon-36) compared to a heavier one (argon-38)
  • This removes previous uncertainty about the ratio in the Martian atmosphere from 1976 measurements from NASA's Viking project and from small volumes of argon extracted from Martian meteorites
  • The ratio is much lower than the solar system's original ratio, as estimated from argon-isotope measurements of the sun and Jupiter
  • This points to a process at Mars that favored preferential loss of the lighter isotope over the heavier one
  • Curiosity measures several variables
  • with the Rover Environmental Monitoring Station (REMS),
  • daily air temperature has climbed steadily since the measurements began eight months ago and is not strongly tied to the rover's location
  • humidity has differed significantly at different places along the rover's route
  • Trails of dust devils have not been seen inside Gale Crater
  • REMS sensors detected many whirlwind patterns during the first hundred Martian days of the mission, though not as many as detected in the same length of time by earlier missions
  • Curiosity will be drilling into another rock where the rover is now, but that target has not yet been selected. The science team will discuss this over the conjunction period
  • For the rest of April, Curiosity will carry out daily activities for which commands were sent in March, using DAN, REMS and the Radiation Assessment Detector (RAD).
  • ChemCam reveals a complex chemical composition of the dust that includes hydrogen, which could be in the form of hydroxyl groups or water molecules
Mars Base

Watch Curiosity's Parachute Flap in the Martian Breeze - 0 views

www.universetoday.com/...ute-flap-in-the-martian-breeze

scibyte89 Curiosity

shared by Mars Base on 04 Apr 13 - No Cached
  • The images were acquired by HiRISE between August 12, 2012 and January 13, 2013
  • The different images show distinct changes in the parachute, which is attached to the backshell that encompassed the rover during launch, flight and descent
  • This type of motion may kick off dust and keep parachutes on the surface bright, to help explain why the parachute from Viking 1 (landed in 1976) remains detectable
  • ...1 more annotation...
  • An animation of seven images from the HiRISE camera on the Mars Reconnaissance Orbiter show a “flapping” of the parachute that allowed the Curiosity rover to descend safely through Mars atmosphere images
Mars Base

How the Air Force and SpaceX Saved Dragon from Doom - 0 views

www.universetoday.com/...-spacex-saved-dragon-from-doom

scibyte89 dragon

shared by Mars Base on 04 Apr 13 - No Cached
  • Barely 11 minutes after I witnessed the spectacular March 1 blastoff of the Dragon atop the SpaceX Falcon 9 rocket from Cape Canaveral, Florida
  • contact had been lost
  • Right after spacecraft separation in low Earth orbit , a sudden and unexpected failure of the Dragon’s critical thrust pods had prevented three out of four from initializing and firing
  • ...12 more annotations...
  • The oxidizer pressure was low in three tanks. And the propulsion system is required to orient the craft for two way communication and to propel the Dragon to the orbiting lab complex
  • The problem was a very tiny change to the check valves that serve the oxidizer tanks
  • Three of the check valves were actually different from the prior check valves that had flown – in a very tiny way. Because of the tiny change they got stuck
  • able to write some new software in real time and upload that to Dragon to build pressure upstream of the check valves and then released that pressure- to give it a kind of a kick
  • that got the valves unstuck and then they worked well
  • difficulty communicating with the spacecraft because it was in free drift in orbit
  • worked closely with the Air Force to get higher intensity, more powerful dishes to communicate with the spacecraft and upload the software
  • there had been a small design change to the check valves by the supplier
  • supplier had made mistakes that we didn’t catch
  • You would need a magnifying glass to see the difference
  • SpaceX had run the new check valves through a series of low pressurization systems tests and they worked well and didn’t get stuck. But SpaceX had failed to run the functional tests at higher pressures
  • SpaceX will revert to the old check valves and run tests to make sure this failure doesn’t happen again
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