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Publishers withdraw more than 120 gibberish papers : Nature News & Comment - 0 views

  • The publishers Springer and IEEE are removing more than 120 papers from their subscription services after a French researcher discovered that the works were computer-generated nonsense.
  • Over the past two years
  • catalogued computer-generated papers that made it into more than 30 published conference proceedings between 2008 and 2013
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  • Sixteen appeared in publications by Springer
  • more than 100 were published by the Institute of Electrical and Electronic Engineers (IEEE),
  • One of the named authors replied t
  • said that he first learned of the article when conference organizers notified his university in December 2013;
  • he does not know why he was a listed co-author on the paper.
  • Among the works
  • a paper published as a proceeding from the 2013 International Conference on Quality, Reliability, Risk, Maintenance, and Safety Engineering, held in Chengdu, China.
  • The authors of the paper, entitled ‘TIC: a methodology for the construction of e-commerce’,
  • in the abstract that they “concentrate our efforts on disproving that spreadsheets can be made knowledge-based, empathic, and compact”.
  • a way to automatically detect manuscripts composed by a piece of software called SCIgen, which randomly combines strings of words to produce fake computer-science papers
  • SCIgen was invented in 2005 by researchers
  • to prove that conferences would accept meaningless papers — and, as they put it, “to maximize amusement”
  • A related program generates random physics manuscript titles on the satirical website arXiv vs. snarXiv.
  • SCIgen is free to download and use, and it is unclear how many people have done so, or for what purposes
  • SCIgen’s output has occasionally popped up at conferences, when researchers have submitted nonsense papers and then revealed the trick.
  • Most of the conferences took place in China, and most of the fake papers have authors with Chinese affiliations.
  • The papers are quite easy to spot,” says Labbé, who has built a website where users can test whether papers have been created using SCIgen.
  • involves searching for characteristic vocabulary generated by SCIgen
  • In April 2010, he used SCIgen to generate 102 fake papers by a fictional author called Ike Antkare
  • showed how easy it was to add these fake papers to the Google Scholar database
  • There is a long history of journalists and researchers getting spoof papers accepted in conferences or by journals to reveal weaknesses in academic quality controls
Mars Base

Memories 'geotagged' with spatial information - 0 views

  • Using a video game in which people navigate through a virtual town delivering objects to specific locations, a team of neuroscientists
  • has discovered how brain cells that encode spatial information form "geotags" for specific memories and are activated immediately before those memories are recalled.
  • work shows how spatial information is incorporated into memories and why remembering an experience can quickly bring to mind other events that happened in the same place
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  • findings provide the first direct neural evidence for the idea that the human memory system tags memories with information about where and when they were formed
  • this study involved playing a simple video game on a bedside computer
  • The game in this experiment involved making deliveries to stores in a virtual city
  • The participants were first given a period where they were allowed to freely explore the city and learn the stores' locations
  • When the game began, participants were only instructed where their next stop was, without being told what they were delivering
  • After they reached their destination, the game would reveal the item that had been delivered, and then give the participant their next stop
  • After 13 deliveries, the screen went blank and participants were asked to remember and name as many of the items they had delivered in the order they came to mind
  • This allowed the researchers to correlate the neural activation associated with the formation of spatial memories (the locations of the stores) and the recall of episodic memories: (the list of items that had been delivered).
  • "Having these patients play our games allows us to record every action they take in the game and to measure the responses of neurons both during spatial navigation and then later during verbal recall."
  • By asking participants to recall the items they delivered instead of the stores they visited, the researchers could test whether their spatial memory systems were being activated
  • map-like nature of the neurons associated with spatial memory made this comparison possible
  • During navigation, neurons in the hippocampus and neighboring regions can often represent the patient's virtual location within the town
  • Using the brain recordings generated while the participants navigated the city, the researchers were able to develop a neural map that corresponded to the city's layout
  • As participants passed by a particular store, the researchers correlated their spatial memory of that location with the pattern of place cell activation recorded
  • With maps of place cell activations in hand, the researchers were able to cross- reference each participant's spatial memories as they accessed their episodic memories of the delivered items
  • given just the place cell activations of a participant
  • could predict, with better than chance accuracy, the item he or she was recalling
  • cannot distinguish whether these spatial memories are actually helping the participants access their episodic memories
  • seeing that this place cell activation plays a role in the memory retrieval processes
  • Earlier neuroscience research
  • had suggested the hippocampus has two distinct roles
  • tracking location information for spatial memory, and
  • recording events for episodic memory
  • This experiment provides further evidence that these roles are intertwined
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Scientists Identify Cause of Japan's Devastating 2011 Tsunami - 0 views

  • In March 2011, a devastating tsunami struck Japan's Tohoku region
  • Now, researchers have uncovered the cause of this tsunami, shedding light on what displaced the seafloor off the northeastern coast of Japan
  • Learning more about the 2011 tsunami and its causes is an important step for monitoring future events.
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  • could help researchers provide earlier warnings
  • During their study
  • scientists underwent a 50-day expedition on the Japanese drilling vessel Chikyu
  • They then drilled three holes in the Japan Trench area in order to study the rupture zone of the 2011 earthquake
  • a fault in the ocean floor where two of Earth's major tectonic plates meet deep beneath the surface of the Pacific Ocean.
  • The conventional view among geologists
  • has been that deep beneath the seafloor, where rocks are strong, movements of the plates can generate a lot of elastic rebound
  • Closer to the surface of the seafloor, where rocks are softer and less compressed, this rebound effect was thought to taper off
  • In fact
  • the largest displacement of plates before the 2011 tsunami occurred in 1960 off the coast of Chile
  • That's when a powerful earthquake displaced seafloor plates by an average of 20 meters
  • The Tohoku earthquake, in contrast, displaced its own plates by 30 to 50 meters.
  • So what caused this unexpectedly violent slip
  • the fault itself is very thin--less than five meters thick in the area sampled.
  • makes it the thinnest plate boundary on Earth.
  • In addition, clay deposits that fill the narrow fault are made of extremely fine sediment, which makes it extremely slippery
  • these findings don't just show researchers a bit more about the past; they also have implications for the future
  • Other subduction zones in the northwest Pacific where this type of clay is present--from Russia's Kamchatka peninsula to the Aleutian Islands--may also be capable of generating similar, huge earthquakes
Mars Base

New strategy to treat multiple sclerosis shows promise in mice - 0 views

  • Scientists
  • have identified a set of compounds that may be used to treat multiple sclerosis (MS) in a new way
  • existing MS therapies
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  • ppress the immune system
  • the compounds boost a population of progenitor cells that can in turn repair MS-damaged nerve fibers
  • cautioned that benztropine is a drug with dose-related adverse side effects, and has yet to be proven effective at a safe dose in human MS patients
  • the newly identified compounds, a Parkinson's disease drug called benztropine, was highly effective in treating a standard model of MS in mice, both alone and in combination with existing MS therapies
  • MS currently affects more than half a million people in North America and Europe, and more than two million worldwide
  • precise triggers are unknown, but certain infections and a lack of vitamin D are thought to be risk factors
  • In MS, immune cells known as T cells infiltrate the upper spinal cord and brain
  • causing inflammation and ultimately the loss of an insulating coating called myelin on some nerve fibers
  • As nerve fibers lose this myelin coating, they lose their ability to transmit signals efficiently, and in time may begin to degenerate
  • resulting symptoms, which commonly occur in a stop-start, "relapsing-remitting" pattern, may include limb weakness, numbness and tingling, fatigue, vision problems, slurred speech, memory difficulties and depression, among other problems
  • Current therapies
  • aim to suppress the immune attack that de-myelinates nerve fibers. But they are only partially effective and are apt to have significant adverse side effects
  • the new study
  • aimed at restoring a population of progenitor cells called oligodendrocytes
  • These cells normally keep the myelin sheaths of nerve fibers in good repair and in principle could fix these coatings after MS damages them
  • oligodendrocyte numbers decline sharply in MS, due to a still-mysterious problem with the stem-like precursor cells that produce them
  • team screened a library of about 100,000 diverse compounds for any that could potently induce OPCs to mature or "differentiate."
  • Several compounds scored well
  • benztropine, had been well characterized and indeed was already FDA-approved for treating Parkinson's disease
  • tests, benztropine showed a powerful ability to prevent autoimmune disease and also was effective in treating it after symptoms had arisen
  • virtually eliminating the disease's ability to relapse
  • benztropine on its own worked about as well as existing treatments, it also showed a remarkable ability to complement these existing treatments
  • two first-line immune-suppressant therapies, interferon-beta and fingolimod
  • Adding even a suboptimal level of benztropine
  • allowed
  • to cut the dose of fingolimod by 90%
  • the same disease-modifying effect as a normal dose
  • that dose-lowering could translate into a big reduction in
  • potentially serious side effects
  • researchers confirmed that benztropine works against disease in this mouse model by boosting the population of mature oligodendrocytes
  • in turn restore the myelin sheaths of damaged nerves
  • even as the immune attack continues
  • benztropine-treated mice showed no change in the usual signs of inflammation, yet their myelin was mostly intact, suggesting that it was probably being repaired as rapidly as it was being destroyed
  • Benztropine is known to have multiple specific effects on brain cells, including the blocking of activity at acetylcholine and histamine receptors and a boosting of activity at dopamine receptors
  • hope to learn more about how
  • its molecular structure might be optimized for this purpose
Mars Base

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

  • 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
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  • 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

April 9 - Today in Science History - Scientists born on April 9th, died, and events - 0 views

  • First astronauts selected
  • In 1959, NASA announced the selection of America's first seven astronauts for project Mercury. Scott Carpenter, Gordon Cooper, John Glenn, Gus Grissom, Wally Schirra, Alan Shepard and Donald Slayton were chosen from 110 applicants. Their training program at Langley, which ranged from a graduate-level course in introductory space science to simulator training and scuba-diving. Project Mercury, NASA's first high profile program, was an effort to learn if humans could survive in space. NASA required astronaut candidates to be male, not over 40 years old, not more than 5' 11" height and in excellent physical condition. On 5 May 1961, Shepard became the first American in space
Mars Base

NASA Mars Rover Curiosity Scoping Out Next Study Area - Mars Science Laboratory - 0 views

  • The mission's investigations at the Kimberley are planned as the most extensive since Curiosity spent the first half of 2013 in an area called Yellowknife Bay
  • At the Kimberley
  • researchers plan to use Curiosity's science instruments to learn more about habitable past conditions and environmental changes.
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  • The rover reached a vantage point for its cameras to survey four different types of rock intersecting in an area called "the Kimberley,"
  • This is the spot on the map we've been headed for, on a little rise that gives us a great view for context imaging of the outcrops at the Kimberley
  • science planning lead for what are expected to be several weeks of observations, sample-drilling and onboard laboratory analysis of the area's rocks
Mars Base

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

  •  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.
Mars Base

Drill Here? NASA's Curiosity Mars Rover Inspects Site - Mars Science Laboratory - 0 views

  • The team operating NASA's Curiosity Mars rover is telling the rover to use several tools this weekend to inspect a sandstone slab being evaluated as a possible drilling target
  • If this target meets criteria set by engineers and scientists, it could become the mission's third drilled rock, and the first that is not mudstone
  • The planned inspection, designed to aid a decision on whether to drill
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  • includes observations with the camera and X-ray spectrometer at the end of the rover's arm, use of a brush to remove dust from a patch on the rock, and readings of composition at various points on the rock with an instrument that fires laser shots from the rover's mast.
  • The first two Martian rocks drilled and analyzed this way were mudstone slabs neighboring each other in Yellowknife Bay, about 2.5 miles (4 kilometers) northeast of the rover's current location
  • Those two rocks yielded evidence of an ancient lakebed environment with key chemical elements and a chemical energy source that provided conditions billions of years ago favorable for microbial life.
  • learn more about the wet process that turned sand deposits into sandstone here
  • the composition of the fluids that bound the grains together
  • Understanding why some sandstones in the area are harder than others also could help explain major shapes of the landscape where Curiosity is working inside Gale Crater.
  • Erosion-resistant sandstone forms a capping layer of mesas and buttes. It could even hold hints about why Gale Crater has a large layered mountain, Mount Sharp, at its center.
Mars Base

May 12 - Today in Science History - Scientists born on May 12th, died, and events - 0 views

  • In 2004, the discovery of what was believed to be the world's oldest seat of learning, the Library of Alexandria, was announced by Zahi Hawass, president of Egypt's Supreme Council of Antiquities during a conference at the University of California. A Polish-Egyptian team had uncovered 13 lecture halls featuring an elevated podium for the lecturer. Such a complex of lecture halls had never before been found on any Mediterranean Greco-Roman site. Alexandria may be regarded as the birthplace of western science, where Euclid discovered the rules of geometry, Eratosthenes measured the diameter of the Earth and Ptolemy wrote the Almagest, the most influential scientific book about the nature of the Universe for 1,500 years
  • Oldest university unearthed
  • In 1936, the Dvorak typewriter keyboard was patented in the U.S. by Dvorak and Dealey (Patent No. 2,040,248). The efficiency experts August Dvorak (a cousin of the composer) and William Dealey studied the typewriter to determine that they could arrange the keys in a new way which would speed up the operators of the typewriter. They designed a keyboard to maximize efficiency by placing common letters on the home row, and make the stronger fingers of the hands do most of the work. By contrast, the original QWERTY layout was designed for the earlier, less efficient typewriters. Previously, speed would result in two type bars hitting each other in their travel, so the original keyboard was laid out to reduce collisions
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  • Dvorak keyboard
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Cartilage, made to order: Living human cartilage grown on lab chip -- ScienceDaily - 0 views

  • The first example of living human cartilage grown on a laboratory chip has been created by scientists
  • The researchers ultimately aim to use their innovative 3-D printing approach to create replacement cartilage
  • Osteoarthritis is marked by a gradual disintegration of cartilage, a flexible tissue that provides padding where bones come together in a joint
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  • is one of the leading causes of physical disability in the United States
  • some treatments can help relieve arthritis symptoms, there is no cure. Many patients with severe arthritis ultimately require a joint replacement
  • artificial cartilage built using a patient's own stem cells could offer enormous therapeutic potential
  • replacement cartilage could also be a game-changer for people with debilitating joint injuries, such as soldiers with battlefield injuries
  • Creating artificial cartilage requires three main elements: stem cells, biological factors to make the cells grow into cartilage, and a scaffold to give the tissue its shape
  • Tuan's 3-D printing approach achieves all three by extruding thin layers of stem cells embedded in a solution that retains its shape and provides growth factors
  • The ultimate vision is to give doctors a tool they can thread through a catheter to print new cartilage right where it's needed in the patient's body
  • other researchers have experimented with 3-D printing approaches for cartilage,
  • method represents a significant step forward because it uses visible light, while others have required UV light, which can be harmful to living cells.
  • In another significant step
  • used the 3-D printing method to produce the first "tissue-on-a-chip" replica of the bone-cartilage interface
  • the chip could serve as a test-bed for researchers to learn about how osteoarthritis develops and develop new drugs
  • Housing 96 blocks of living human tissue 4 millimeters across by 8 millimeters deep
  • As a next step, the team is working to combine their 3-D printing method with a nanofiber spinning technique they developed previously
  • They hope combining the two methods will provide a more robust scaffold and allow them to create artificial cartilage that even more closely resembles natural cartilage
Mars Base

Demo of mind-controlled exoskeleton planned for World Cup - 0 views

  • The World Cup opening ceremony
  • June 12
  • a standout for athletes and their fans but yet another eye-opener may make the Sao Paulo stadium opener long remembered globally
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  • a mind-controlled exoskeleton designed to enable a paralyzed person to walk is to make its debut.
  • BBC report provided the latest developments in the robotic suit. "If all goes as planned," wrote Alejandra Martins, "the robotic suit will spring to life in front of almost 70,000 spectators and a global audience of billions of people."
  • The exoskeleton was developed by an international team of scientists, part of the Walk Again Project, and described by the BBC report as a "culmination" of over 10 years of work
  • The goal is to show the brain-controlled exoskeleton during the opening ceremony of the 2014 FIFA World Cup.
  • The (DiVE) website talks about the day when "the first ceremonial kick in the World Cup game may be made "by a paralyzed teenager, who, flanked by the two contending soccer teams, will saunter onto the pitch clad in a robotic body suit."
  • According to the BBC, since November, Nicolelis has been training eight patients at a lab in Sao Paulo, amidst "media speculation that one of them will stand up from his or her wheelchair and deliver the first kick of this year's World Cup.")
  • the exoskeleton is being controlled by brain activity and it is relaying feedback signals to the patient.
  • The patient wears a cap which picks up brain signals and relays them to a computer in the backpack, decoding the signals and sending them to the legs.
  • A battery in the backpack allows for around two hours' use. The robotic suit is powered by hydraulics.
  • Many different companies helped to build the skeleton's components
  • they used a lot of 3-D printing technology for purposes of both speed and achieving strong but light materials, along with using standard aluminum parts
  • "When the foot of the exoskeleton touches the ground there is pressure, so the sensor senses the pressure and before the foot touches the ground we are also doing pre-contact sensing. It's a new way of doing skin sensing for robots," Cheng
  • Dr Gordon Cheng, at the Technical University of Munich
  • Duke University in November announced that in a study led by Duke researchers, monkeys learned to control the movement of both arms on an avatar using just their brain activity.
Mars Base

Direct Image of an Exoplanet 155 Light Years Away - 0 views

  • This week, an international team of researchers
  • announced the discovery of an exoplanet
  • 155 light years
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  • world is estimated to be 11 times the mass of Jupiter — placing it just under the lower mass limit for brown dwarf status
  • orbits its host star 2,000x farther than the distance from Earth to the Sun once every 80,000 (!) years
  • The primary star, GU Psc A, is an M3 red dwarf weighing in at 35% the mass of our Sun and is just 100 million years old
  • researchers targeted GU Psc after it was determined to be a member of the AB Doradus moving group of relatively young stars, which are prime candidates for exoplanet detection
  • The fact that GU Psc B was captured by direct imaging at 155 light years distant is amazing
  • The team was able to discern this curious planet by utilizing observations from the W.M. Keck observatory, the joint Canada-France-Hawaii Telescope, the Gemini Observatory and the Observatoire Mont-Mégantic in Québec.
  • there are not a lot of exoplanets that were detected ‘directly’ so far
  • The few planets for which we have an actual image are interesting because we can analyze their light directly, and thus learn much more about them
  • researcher Marie-Ève Naud and her co-advisor Étienne Artigau
  • also one of the “coolest” planets that have been directly imaged, showing methane absorption
  • it is certainly the most distant exoplanet to a main-sequence star that has been found so far
  • This distance makes GU Psc b very interesting from a theoretical point of view, because it’s hard to imagine how it could have formed in the protoplanetary disk of its star
  • current working definition of an exoplanet is based solely on mass (<13 Jupiter masses), so GU Psc b probably formed in a way that is more similar to how stars formed
  • how are astronomers certain that PU Psc b is related to its host and not a foreground or background object?
  • As the host star, GU Psc is relatively nearby; it displays a significant apparent proper motion
  • relative to distant background stars and galaxies.
  • On images taken one year apart with WIRCam on the Canada-France-Hawaii Telescope, we observed that the companion displays the same big proper motion, i.e. they move together in the plane of the sky, while the rest of the stars in the field don’t
  • most planet hunting techniques using direct imaging involve state-of-the-art adaptive optics systems, but we used ‘standard’ imaging without any exotic techniques
  • To find this planet, we used very sensitive ‘standard’ imaging,
  • we chose carefully the wavelengths where planets display colors that are unlike most other astrophysical objects such as stars and galaxies
Mars Base

'Mississippi Baby' now has detectable HIV, researchers find -- ScienceDaily - 0 views

  • The child known as the 'Mississippi baby' -- an infant seemingly cured of HIV that was reported as a case study of a prolonged remission of HIV infection
  • now has detectable levels of HIV after more than two years of not taking antiretroviral therapy without evidence of virus
  • an infant seemingly cured of HIV that was reported as a case study of a prolonged remission of HIV infection
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  • now has detectable levels of HIV after more than two years of not taking antiretroviral therapy without evidence of virus
  • "Scientifically, this development reminds us that we still have much more to learn about the intricacies of HIV infection and where the virus hides in the body. The NIH remains committed to moving forward with research on a cure for HIV infection."
  • NIAID Director Anthony S. Fauci, M.D.
  • The researchers planning the clinical trial will now need to take this new development into account
  • The child was born prematurely in a Mississippi clinic in 2010 to an HIV-infected mother who did not receive antiretroviral medication during pregnancy and was not diagnosed with HIV infection until the time of delivery
  • Because of the high risk of HIV exposure, the infant was started at 30 hours of age on liquid, triple-drug antiretroviral treatment.
  • Testing confirmed within several days that the baby had been infected with HIV. At two weeks of age, the baby was discharged from the hospital and continued on liquid antiretroviral therapy
  • The baby continued on antiretroviral treatment until 18 months of age, when the child was lost to follow up and no longer received treatment
  • when the child was again seen by medical staff five months later, blood samples revealed undetectable HIV levels (less than 20 copies of HIV per milliliter of blood (copies/mL)) and no HIV-specific antibodies
  • The child continued to do well in the absence of antiretroviral medicines and was free of detectable HIV for more than two years
  • Repeat viral load blood testing performed 72 hours later confirmed this finding
  • Additionally, the child had decreased levels of
  • a key component of a normal immune system, and the presence of HIV antibodies
  • Based on these results, the child was again started on antiretroviral therapy
  • To date, the child is tolerating the medication with no side effects and treatment is decreasing virus levels
  • Genetic sequencing of the virus indicated that the child's HIV infection was the same strain acquired from the mother
  • In light of the new findings, researchers must now work to better understand what enabled the child to remain off treatment for more than two years without detectable virus or measurable immunologic response
  • what might be done to extend the period of sustained HIV remission in the absence of antiretroviral therapy
  • "Typically, when treatment is stopped, HIV levels rebound within weeks, not years."
  • "The prolonged lack of viral rebound, in the absence of HIV-specific immune responses, suggests that the very early therapy not only kept this child clinically well, but also restricted the number of cells harboring HIV infection," said Katherine Luzuriaga, M.D., professor of molecular medicine, pediatrics and medicine at the University of Massachusetts
  • The case
  • indicates that early antiretroviral treatment in this HIV-infected infant did not completely eliminate the reservoir of HIV-infected cells that was established upon infection
  • may have considerably limited its development and averted the need for antiretroviral medication over a considerable period
  • during a routine clinical care visit earlier this month, the child, now nearly 4 years of age, was found to have detectable HIV levels in the blood
Mars Base

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

  • 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
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  • 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
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Researchers identify brain cells responsible for keeping us awake - 0 views

  • Bright light makes it easier to stay awake
  • Very bright light not only arouses us but is known to have antidepressant effects.
  • Bright light makes it easier to stay awake.
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  • dark rooms can make us sleepy.
  • researchers at UCLA have identified the group of neurons that mediates whether light arouses us — or not
  • the cells necessary for a light-induced arousal response are located in the hypothalamus
  • an area at the base of the brain responsible for, among other things, control of the autonomic nervous system, body temperature, hunger, thirst, fatigue — and sleep.
  • the activity of hypocretin neurons in their WT littermates was maximized when working for positive rewards during the light phase, but the cells were not activated when performing the same tasks in the dark phase.
  • These cells release a neurotransmitter called hypocretin
  • This current finding explains prior work in humans that found that narcoleptics lack the arousing response to light, unlike other equally sleepy individuals
  • researchers examined the behavioral capabilities of mice that had their hypocretin genetically "knocked-out" (KO mice) and compared them with the activities of normal, wild-type mice (WT) that still had their hypocretin neurons
  • they found that the KO mice were only deficient at working for positive rewards during the light phase
  • During the dark phase, however, these mice learned at the same rate as their WT littermates and were completely unimpaired in working for the same rewards
  • This same UCLA research group earlier determined that the loss of hypocretin was responsible for narcolepsy and the sleepiness associated with Parkinson's disease
  • findings suggest that administering hypocretin and boosting the function of hypocretin cells will increase the light-induced arousal response
  • Conversely, blocking their function by administering hypocretin receptor blockers will reduce this response and thereby induce sleep
  • implications for treating sleep disorders as well as depression
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New drug raises potential for cancer treatment revolution - 0 views

  • A new study
  • has developed a new drug that can manipulate the body's natural signalling and energy systems, allowing the body to attack and shut down cancerous cells.
  • ZL105,
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  • the drug is a compound based on the precious metal iridium
  • The study has found ZL105 could potentially replace currently used anticancer drugs
  • which become less effective over time, cause a wide-range of side-effects and damage healthy cells as well as cancerous.
  • study co-author
  • said "The energy-producing machinery in cancer cells works to the limit as it attempts to keep up with quick proliferation and invasion
  • This makes cancer cells susceptible to minor changes in the cell 'power-house'.
  • drug pushes cancer cells over the limit causing them to slow and shut down, whilst normal cells can cope with its effects
  • Preliminary data indicate that the novel drug may be ten times more effective in treating ovarian, colon, melanoma, renal, and some breast cancers, according to data obtained by the US National Cancer Institute
  • researchers now aim to expand the study to cancers that are inherently resistant to existing drugs and to those which have developed resistance after a first round of chemotherapy treatments.
  • Existing cancer treatments often become less effective after the first course, as cancer cells learn how they are being attacked
  • The drug we have developed is a catalyst and is active at low doses
  • It can attack cancer cells in multiple ways at the same time, so the cancer is less able to adapt to the treatment
  • means the new drugs could be much more effective than existing treatments
  • Platinum-based drugs are used in nearly 50% of all chemotherapeutic regimens
  • damaging DNA and cannot select between cancerous and non-cancerous cells
  • leading to a wide-range of side-effects from renal failure to neurotoxicity, ototoxicity, nausea and vomiting
  • the new iridium-based drug is specifically designed not to attack DNA,
  • growth
  • novel mechanism of action, meaning that it could not only dramatically slow down and halt cancer growth, but also significantly reduce the side effects
  • This research could also lead to substantial improvements in cancer survival rates
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ISEE-3 Reboot Project Status and Schedule for First Contact - Space College - 0 views

  • Technical Progress The Learning Curve
  • reliminary evaluation of the spacecraft and its systems so as to better understand it.
  • Most of the best information that we have been able to find has been from the people who worked on the project in the 1980's when the spacecraft was fully operational
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  • have also obtained several documents from NASA as part of the development of our Space Act Agreement
  • Since there is no computer on board the ISEE-3 spacecraft our task is actually much easier since we are going to be directly commanding various subsystems
  • This is an ongoing process and we have, as usual, dug some of the pertinent information out of 35 year old IEEE or AIAA papers that are publicly available
  • The ISEE-3/ICE spacecraft was never really designed to be an interplanetary cruiser and thus the thrusters on board are very small
  • estimate that if we wait until mid-June to do the course correction that it will take 17 hours of thrusting to get the course change of about 40 meters/second that we will need at that time
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