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Scientists have discovered four species of Brazilian insects in which the females possess a penis and the males possess a vagina. This announcement, made today in the journal Current Biology, represents the first documented instance of a "female penis" in the animal kingdom.
Contrary to popular belief, the presence or absence of certain sex organs isn't the determining factor when deciding which animal of a species is female and which is male. In fact, biologists don't use sex chromosomes either. They actually rely on the size of an animal's gametes — sperm in males and oocytes in females. As the rule goes, females are the sex that contribute the largest gametes, whereas males are the sex that contribute the smallest gametes and therefore expend the least amount of energy on producing these cells. So, in this particular instance of sex-role reversal, the convention still applies: the female in these species of insect produces the largest gametes — egg cells. She simply also happens to sport a penis that she introduces into the male's vagina during copulation.
"The female penis is a completely novel structure," said Yoshizawa Kazunori, an entomologist at Japan's Hokkaido University and co-author of the study, in an email toThe Verge. Except for producing the larger gametes and having an egg-laying apparatus, the females in these four species of winged insects, called Neotrogla, seem to have become "very masculine" over evolutionary time, Kazunori added. The appearance of such a novel structure is exceptionally rare, he said, and "may be comparable with the origin of insect wings."
After finally getting their hands on full clinical study reports, independent reviewers say the antiviral drug is ineffective.
Governments have spent billions of dollars stockpiling the antiviral medication Tamiflu. Earlier reviews of the drug called into question just how effective it was, and the latest analysis, published today (April 10) in the British Medical Journal (BMJ), concludes that the money has been going “down the drain.”
An international team found that while Tamiflu might reduce the duration of flu symptoms by half a day, there’s no evidence that it reduces hospital admissions or complications of an infection. On top of that, the antiviral’s side effects include nausea and vomiting. “There is no credible way these drugs could prevent a pandemic,” Carl Heneghan, one of authors of the review and a professor at Oxford University,told reporters.
The data for this most recent review came from full study reports—data generated by clinical trials that are usually not open for scrutiny by independent researchers. Efforts by the BMJ and the research team convinced drugmaker Roche, which markets Tamiflu, to release the reports.
Fiona Godlee, an editor at BMJ, said that the picture of Tamiflu was previously much more positive than after the full study reports were disclosed. “Why did no one else demand this level of scrutiny before spending such huge sums on one drug?” she said at a press briefing. “The whole story gives an extraordinary picture of the entrenched flaws in the current system of drug regulation and drug evaluation.”
Roche stands by the utility of Tamiflu. “We fundamentally disagree with the overall conclusions” of the review, the company told MedPage Today. And others have said that the results don’t necessitate an end to stockpiling the drug. Sabrina Spinosa of the European Medicines Agency (EMA), which approved the use of Tamiflu in 2002, told Nature that the agency had reviewed the same clinical trial reports. “The review does not raise any new concerns,” she said, adding that the EMA maintains its position on the risks and benefits of Tamiflu.
Google engineers working on software to automatically read home and business addresses off photographs taken by Street View vehicles, have created a product so good that not only can it be used for address reading, it can solve CAPTCHAs, as well.
CAPTCHAs are, of course, words that have been intentionally distorted presented to live humans who wish to enter a web site—to gain access, they must correctly type the word into a box. CAPTCHAs are believed to be difficult if not impossible for spam bots to decipher, thus they serve to protect the site—at least for now.
It's sort of ironic actually, that software has inadvertently been created that thwarts the efforts of other software engineers attempting to keep spam bots from accessing web sites. The finding was posted by Google Product Manager Vinay Shet on the Google blog.
To make Google Street View (part of Google Maps) ever smarter, engineers have been hard at work developing a sophisticated neural network based on both prior research and new image recognition techniques. The aim is to make Google's products more accurate. To display an image of a house or building given an address by a user takes a lot of computer smarts—Google connects new addresses to older known addresses, constantly updating its databases.
Presumably, the goal is to map every building in the known world to an address. But the work has produced an unexpected by-product, the very same software developed for Street View can also be used to decipher CAPTCHAs with 96 percent accuracy (98.8 percent when working on Google's own reCAPTCHA).
Scientists in Canada have made DNA cubes that are programmed to unzip and reveal molecules locked inside them in response to a carefully chosen trigger. Hanadi Sleiman and colleagues at McGill University and the Jewish General Hospital in Montreal, designed the cubes to release the drug cargo they might be carrying only in diseased cells and not normal cells.
‘In the future, we would like to use our DNA cubes in the treatment of cancer and other diseases with a genetic component,’ says Sleiman. The cube opens into a flat assembly when a specific RNA sequence, in this case a gene product that is unique to prostate cancer cells, binds to two single-stranded DNA overhangs on the corners of the cube, disrupting the hydrogen-bonds that maintain the cube’s shape. Sleiman says it would be easy to change the sequence to which the cube responds and since the cube has two overhangs, ‘it would also be possible to make a cube that responds to two different triggers.’
The DNA cube was also modified with hydrophobic and hydrophilic chains to modulate its cellular uptake and prevent enzymatic degradation.
‘Compared with previous DNA origami-based designs the present system does not rely on the use of M13 [bacteriophage] DNA and can therefore be applied to many targets,’ comments Hiroshi Sugiyama, a DNA nanotechnology expert at Kyoto University in Japan.
Most proteins, including immunoglobulins, human virus receptors, and viral-coded proteins, are post-translationally modified with sugars or sugar chains that are generically referred to as glycans. Glycans are primarily classified as N-linked or O-linked oligosaccharides, depending on whether they are bound to the amide group of asparagine (N-linked) or the hydroxyl group of serine or threonine (O-linked). Glycans are associated with protein conformation, folding, solubility, stability, half-life, and antigenicity and are the moieties recognized by glycan-binding proteins. The congenital disorders of glycosylation (CDGs) are genetic disorders affecting the N-glycosylation process. CDGs are divided into defects in the synthesis of N-glycans (CDG-I) and defects in the processing of N-glycans (CDG-II). CDG-IIb (Online Mendelian Inheritance in Man database number, 606056) is caused by mutations in the gene encoding MOGS (also known as glucosidase 1). MOGS is an enzyme that is expressed in the endoplasmic reticulum and is involved in the trimming of N-glycans.1 A single case of CDG-IIb has been reported; the patient died at the age of 74 days from severe neurologic complications.2 In this study, scientists evaluated the immune system and susceptibility to viral diseases in two siblings with CDG-IIb who presented with severe hypogammaglobulinemia but not many infections.
Tasmanian Devil Facial Tumor Disease (DFTD) has ravaged the world's largest carnivorous marsupial since it emerged in 1996, resulting in a population decline of over 90%. Conservation work to defeat the disease has including removing infected individuals from the population and new research explains how this gives us a unique opportunity to understand how human selection alters the evolution of cancerous cells. DFTD is an asexually reproducing clonal cell line, which during the last 16 years has been exposed to negative effects as infected devils, approximately 33% of the population, have been removed from one site, the Forestier Peninsula, in Tasmania between 2006 and 2010.
However, this parasitical disease has been able survive and counteract the effect of deleterious mutation, genomic instability as well as being able to infect more than 100,000 devils.
"In this study, we focus on the evolutionary response of DFTD to a disease suppression trial," said Beata Ujvari, from the, The University of Sydney. "Tumors collected from devils subjected to the removal programme showed accelerated temporal evolution of tetraploidy compared with tumors from other populations where no increase of tetraploid tumors were observed."
The disease eradication trial provides a unique opportunity to discover the long-term effects of human selection on DFTD evolution and to explore this, the team collected tumour tissue samples between 2006 and 2011 at 11 sites within the DFTD affected areas of Tasmania.
"Our study clearly demonstrates that DFTD tumors are able to rapidly respond to increased selection and adapt to a selective regime," said Ujvari. "The results suggest that ploidization may offer yet another pathway to which DFTD is able to adapt to the ever-changing evolutionary landscape sculptured by the devils' immune system. Our study is the first to show that anthropogenic selection may enhance cancer evolution in the wild, and it therefore cautions about what measures we employ to try to halt the spread of this devastating disease."
Beata Ujvari, Anne-Maree Pearse, Kate Swift, Pamela Hodson, Bobby Hua, Stephen Pyecroft, Robyn Taylor, Rodrigo Hamede, Menna Jones, Katherine Belov, Thomas Madsen. Anthropogenic selection enhances cancer evolution in Tasmanian devil tumours. Evolutionary Applications, 2014; 7 (2): 260 DOI: 10.1111/eva.12117
NASA is preparing for an April 14 launch to the International Space Station aboard the SpaceX-3 mission to test NASA’s first space-to-Earth optical communication system.
The Optical Payload for Lasercomm Science (OPALS) system will demonstrate up to 50 megabits per second transmission, compared to 200 to 400 kilobits per second for many deep-space missions. Future deep space optical communication systems will provide more than one gigabit per second from Mars, NASA says.
Fast laser communications between Earth and spacecraft like the space station or NASA’s Mars Curiosity rover would enhance their connection to engineers and scientists on the ground as well as to the public, NASA says.
However, this mission is only intended for testing. As the space station orbits Earth, a ground telescope tracks it and transmits a laser beacon to OPALS. While maintaining lock on the uplink beacon, the orbiting instrument’s flight system will downlink a modulated laser beam with a formatted video.
Each demonstration, or test, will last approximately 100 seconds as the station instrument and ground telescope maintain line of sight. It will be used to study pointing, acquisition and tracking of the very tightly focused laser beams, taking into account the movement of the space station, and to study the characteristics of optical links through Earth’s atmosphere. NASA will also use OPALS to educate and train personnel in the operation of optical communication systems.
NASA says the success of OPALS will provide increased impetus for operational optical communications in NASA missions, noting that “the space station is a prime target for multi-gigabit-per-second optical links.”
Drilling operations at several natural gas wells in southwestern Pennsylvania released methane into the atmosphere at rates that were 100 to 1,000 times greater than federal regulators had estimated, new research shows.
Using a plane that was specially equipped to measure greenhouse gas emissions in the air, scientists found that drilling activities at seven well pads in the booming Marcellus shale formation emitted 34 grams of methane per second, on average. The EPA has estimated that such drilling releases between 0.04 grams and 0.30 grams of methane per second.
The study, published Monday in the Proceedings of the National Academy of Sciences, adds to a growing body of research that suggests the EPA is gravely underestimating methane emissions from oil and gas operations. The agency is expected to issue its own analysis of methane emissions from the oil and gas sector as early as Tuesday, which will give outside experts a chance to assess how well regulators understand the problem.
Carbon dioxide released by the combustion of fossil fuels is the biggest contributor to climate change, but methane — the chief component of natural gas — is about 20 to 30 times more potent when it comes to trapping heat in the atmosphere. Methane emissions make up 9% of the country's greenhouse gas emissions and are on track to increase, according to the White House.
The Pennsylvania study was launched in an effort to understand whether the measurements of airborne methane matched up with emissions estimates based on readings taken at ground level, the approach the EPA and state regulators have historically used.
Researchers flew their plane about a kilometer above a 2,800 square kilometer area in southwestern Pennsylvania that included several active natural gas wells. Over a two-day period in June 2012, they detected 2 grams to 14 grams of methane per second per square kilometer over the entire area. The EPA’s estimate for the area is 2.3 grams to 4.6 grams of methane per second per square kilometer.
A new jet-lag mobile app called Entrain released by University of Michigan mathematicians reveals previously unknown shortcuts that can help travelers entrain (synchronize) their circadian rhythms to new time zones as efficiently as possible.
Entrain is built around the premise that light, particularly from the sun and in wavelengths that appear to our eyes as the color blue, is the strongest signal to regulate circadian rhythms. These fluctuations in behaviors and bodily functions, tied to the planet’s 24-hour day, do more than guide us to eat and sleep. They govern processes in each one of our cells.
The study, published April 10, 2014, in Public Library of Science Computational Biology (open access journal), relies on two leading mathematical models that have been shown to accurately describe human circadian rhythms. The researchers used these equations and a technique called optimal control theory to calculate ideal adjustment schedules for more than 1,000 possible trips.
The app gives users access to these schedules. Start by entering your typical hours of light and darkness in your current time zone, then choose the time zone you’re traveling to and when, as well as the brightest light you expect to spend the most time in during your trip (indoor or outdoor.) The app offers a specialized plan and predicts how long it will you take to adjust.
The shortcuts the app offers are custom schedules of light and darkness depending on the itinerary. The schedules boil down to one block of time each day when you should seek the brightest light possible and another when you should put yourself in the dark, or at least in dim light. You don’t even have to be asleep.
If you must go outside, you can wear pink-tinted glasses to block blue wavelength light, the researchers say. And if the app prescribes “bright outdoor light” in the middle of the night, a therapeutic lightbox can do the job — yes, its shortcuts sometimes require odd hours.
The Entrain app is available now as a free app in the Apple store.
A below-ground experiment at the South Pole has now discovered three of the highest-energy neutrinos ever found, particles that may be created in the most violent explosions of the universe. These neutrinos all have energies at the absurdly high scale of petaelectronvolts — roughly the energy equivalent of one million times a proton’s mass. (As Albert Einstein showed in his famous E = mc2 equation, energy and mass are equivalent, and such a large amount of mass converts to an extreme level of energy.) The experiment, called IceCube, reported the discovery of the first two — nicknamed Ernie and Bert — last year, and announced the third Monday here at the American Physical Society meeting. “Internally, it’s known as Big Bird,” said IceCube physicist Chris Weaver of the University of Wisconsin–Madison.
These neutrinos are valuable because they are extremely standoffish, rarely ever interacting with other particles, and are uncharged, so their direction is never swayed by magnetic fields in the universe. Thus, their trajectories should point straight back to their source, which astronomers think could be a variety of intense events such as humongous black holes accreting matter, explosions called gamma-ray bursts or galaxies forming stars at furious rates.
This penchant for noninteraction also makes neutrinos extremely difficult to detect. The IceCube experiment looks for the very rare occasions when neutrinos collide with atoms in a cubic kilometer of ice buried underneath the South Pole. Such shielding is necessary to filter out collisions from other particles, but does not inhibit neutrinos. The experiment capitalizes on the naturally pure ice there, using a region that extends twice the depth of the Grand Canyon underground.
Thousands of light detectors are imbedded in the ice to catch the little blips of light created when neutrinos are caught. Such interactions are so infrequent that IceCube researchers had to search for two years to find these three high-energy neutrinos. During that time span the instrument also detected 34 neutrinos of somewhat lower energies. Some of these neutrinos are thought to be contamination created when charged particles called cosmic rays hit Earth’s atmosphere, but some portion of IceCube’s haul likely came directly from violent processes in the cosmos. Those particles are called astrophysical neutrinos. “It looks like we have reached compelling evidence for astrophysical neutrinos,” said U.W.–Madison physicist Albrecht Karle, a member of the IceCube team.
Researchers are programming robots to communicate with people using human-like body language and cues, an important step toward bringing robots into homes.
Researchers at the University of British Columbia enlisted the help of a human-friendly robot named Charlie to study the simple task of handing an object to a person. Past research has shown that people have difficulty figuring out when to reach out and take an object from a robot because robots fail to provide appropriate nonverbal cues.
“We hand things to other people multiple times a day and we do it seamlessly,” says AJung Moon, a PhD student in the Department of Mechanical Engineering. “Getting this to work between a robot and a person is really important if we want robots to be helpful in fetching us things in our homes or at work.”
Moon and her colleagues studied what people do with their heads, necks and eyes when they hand water bottles to one another. They then tested three variations of this interaction with Charlie and the 102 study participants.
Programming the robot to use eye gaze as a nonverbal cue made the handover more fluid. Researchers found that people reached out to take the water bottle sooner in scenarios where the robot moved its head to look at the area where it would hand over the water bottle or looked to the handover location and then up at the person to make eye contact.
“We want the robot to communicate using the cues that people already recognize,” says Moon. “This is key to interacting with a robot in a safe and friendly manner.”
For the past 50 years, our efforts to detect extraterrestrial civilizations have largely focused on the search for radio emissions. But this is hardly the only strategy at our disposal. Here are 14 intriguing ways we could prove that aliens really exist:
After years of failed attempts, researchers have successfully generated stem cells from adults. The process could provide a new way for scientists to generate healthy replacements for diseased or damaged cells in patients
After years of failed attempts, researchers have finally generated stem cells from adults using the same cloning technique that produced Dolly the sheep in 1996.
The process, known as nuclear transfer, involves taking the DNA from a donor and inserting it into an egg that has been stripped of its DNA. The resulting hybrid is stimulated to fuse and start dividing; after a few days the “embryo” creates a lining of stem cells that are destined to develop into all of the cells and tissues in the human body. Researchers extract these cells and grow them in the lab, where they are treated with the appropriate growth factors and other agents to develop into specific types of cells, like neurons, muscle, or insulin-producing cells.
Reporting in the journal Cell Stem Cell, Dr. Robert Lanza, chief scientific officer at biotechnology company Advanced Cell Technology, and his colleagues found that tweaking the Oregon team’s process was the key to success with reprogramming the older cells. Like the earlier team, Lanza’s group used caffeine to prevent the fused egg from dividing prematurely. Rather than leaving the egg with its newly introduced DNA for 30 minutes before activating the dividing stage, they let the eggs rest for about two hours. This gave the DNA enough time to acclimate to its new environment and interact with the egg’s development factors, which erased each of the donor cell’s existing history and reprogrammed it to act like a brand new cell in an embryo.
The team, which included an international group of stem cell scientists, used 77 eggs from four different donors. They tested their new method by waiting for 30 minutes before activating 38 of the resulting embryos, and waiting two hours before triggering 39 of them. None of the 38 developed into the next stage, while two of the embryos getting extended time did. “There is a massive molecular change occurring. You are taking a fully differentiated cell, and you need to have the egg do its magic,” says Lanza. “You need to extend the reprogramming time before you can force the cell to divide.”
While a 5% efficiency may not seem laudable, Lanza says that it’s not so bad given that the stem cells appear to have had their genetic history completely erased and returned to that of a blank slate. “This procedure works well, and works with adult cells,” says Lanza.
The results also teach stem cell scientists some important lessons. First, that the nuclear transfer method that the Oregon team used is valid, and that with some changes it can be replicated using older adult cells. “It looks like the protocols we described are real, they are universal, they work in different hands, in different labs and with different cells,” says Shoukhrat Mitalopov, director of the center for embryonic cell and gene therapy at Oregon Health & Science University, and lead investigator of that study.
A new visualization of data from a nuclear weapons warning network, to be unveiled by B612 Foundation CEO Ed Lu during the evening event at Seattle's Museum of Flight, shows that "the only thing preventing a catastrophe from a 'city-killer' sized asteroid is blind luck."
Since 2001, 26 atomic-bomb-scale explosions have occurred in remote locations around the world, far from populated areas, made evident by a nuclear weapons test warning network. In a recent press release B612 Foundation CEO Ed Lu states:
"This network has detected 26 multi-kiloton explosions since 2001, all of which are due to asteroid impacts. It shows that asteroid impacts are NOT rare—but actually 3-10 times more common than we previously thought. The fact that none of these asteroid impacts shown in the video was detected in advance is proof that the only thing preventing a catastrophe from a 'city-killer' sized asteroid is blind luck. The goal of the B612 Sentinel mission is to find and track asteroids decades before they hit Earth, allowing us to easily deflect them."
The B612 Foundation is partnered with Ball Aerospace to build the Sentinel Infrared Space Telescope Mission. Once positioned in solar orbit closer to the Sun from Earth, Sentinel will look outwards in infrared to detect hundreds of thousands of as-yet unknown near-Earth objects over 140 meters in size. The privately-funded spacecraft is slated to launch in 2017-18 aboard a SpaceX Falcon 9 rocket.
In addition to Lu, Space Shuttle astronaut Tom Jones and Apollo 8 astronaut Bill Anders will be speaking at the event, titled "Saving the Earth by Keeping Big Asteroids Away."
Five hundred light years from Earth, Kepler-186f orbits in the habitable zone of its red dwarf star.
A team of astrophysicists at the SETI Institute and NASA's Ames Research Center has just reached a major milestone in the search for life-supporting planets outside our solar system. For the first time, they have discovered an Earth-sized planet nestled in the temperate, liquid-water supporting distance from its star—the so-called habitable zone.
"This is a historic discovery," says Geoff Marcy, an astronomer at the University of California, Berkeley who was not involved in the research, "it's the best case for a habitable planet yet found."
The planet, called Kepler-186f, lies 500 light years from Earth. Scientists discovered it using the now-defunct, Kepler telescope. Between 2009 and 2013 (before a mechanical failure crippled the $600 million planet-hunter) the Kepler telescope tracked roughly 150,000 stars in a small patch of sky, searching for stars that dim at regular intervals as planets pass in front of them. And despite the telescope's premature demise, astronomers still comb through the massive trove of publicly available data, which is how planets such as the one announced today continue to tumble out of the sky.
The research team estimates that Kepler-186f is only about 10 percent larger than Earth. It orbits its star every 130 days, and inhabits the chillier end of its star's habitable zone. "The temperature on the planet is likely cool, similar to dawn or dusk on a spring day," Marcy says.
Unlike Earth, Kepler-186f orbits a red dwarf star, one roughly half the size of our sun. Red dwarfs are the most abundant type of stars in the sky—cooler than our sun but more volatile during their early life. Because of Kepler-186f's vast distance from Earth, and the fact that the Kepler telescope's can reveal only the size and orbit of the planet, most of the other details about the planet remain murky at best.
"We can say it's probably rocky," says Tom Barclay, an astrophysicist with the NASA Ames Research Center team. "And because the planet is closer to its star, its days are likely much longer than those on Earth." As for the planet's atmosphere, composition, and whether it harbors liquid water, nobody can say. "And it's important to note that just because this planet is in the habitable zone—that it could support water—that doesn't mean that it is habitable," he says.
Nonetheless, the fact that the planet's size and distance from its star are right for life (as we know it) has many researchers excited.
"For literally thousands of years people have wondered: Are there planets like Earth out there?" says Jeff Coughlin, a SETI astronomer with the research team. "And although we've started to find over the years that yes, planets are out there and are quite common, most of them have been rather large gas giants, much like Jupiter. We still haven't found a definitive Earth analogue—a planet with the right size and right temperature. But we are now getting close."
British scientists' identification of Juno molecule opens door to new developments in fertility treatment and contraception.
A fundamental key to fertility has been uncovered by British scientists with the discovery of an elusive protein that allows eggs and sperm to join together. The molecule – named Juno after the Roman goddess of fertility – sits on the egg surface and binds with a male partner on a fertilising sperm cell.
Japanese researchers identified the sperm protein in 2005, sparking a decade-long hunt for its "mate". Understanding the process by which the molecules interact opens the door to new developments in fertility treatment and contraception.
"We have solved a long-standing mystery in biology by identifying the molecules displayed on all sperm and egg that must bind each other at the moment we were conceived," said lead researcher Dr Gavin Wright, from the Wellcome Trust Sanger Institute in Hinxton, Cambridgeshire.
"Without this essential interaction, fertilisation just cannot happen. We may be able to use this discovery to improve fertility treatments and develop new contraceptives."
The Sanger Institute team first created an artificial version of the sperm protein, called Izumo1 after a Japanese marriage shrine.
This was then used to search for binding partners on the surface of the egg. A single protein, Juno, was identified as Izumo1's "other half".
Juno's importance to fertility was revealed by female laboratory mice engineered to produce eggs lacking the molecule.
All the animals were infertile, their eggs incapable of fusing with normal sperm. Male mice missing Izumo1 were also unable to conceive, highlighting this protein's role in male fertility.
The research, reported in the journal Nature, also suggests that Juno plays a role in preventing additional sperm fusing with an already fertilized egg.
After the initial binding of sperm and egg, Juno bows out, becoming virtually undetectable after 40 minutes, the scientists found.
This may help explain why as soon as an egg is fertilised by one sperm cell it puts up a barrier against others.
Fertilisation involving more than one sperm would lead to the formation of abnormal doomed embryos with too many chromosomes.
Juno belongs to a family of "folate receptor" proteins, but unlike its brethren is unable to bind to folic acid. The researchers looked at three folate receptors, and found that only Juno interacted with Izumo1.
The fate of classical information incident on a quantum black hole has been the subject of an ongoing controversy in theoretical physics, because a calculation within the framework of semi-classical curved-space quantum field theory appears to show that the incident information is irretrievably lost, in contradiction to time-honored principles such as time-reversibility and unitarity. Within this framework embedded in quantum communication theory that signaling from past to future infinity in the presence of a Schwarzschild black hole can occur with arbitrary accuracy, and thus that classical information is not lost in black hole dynamics. The calculation relies on a treatment that is manifestly unitary from the outset, where probability conservation is guaranteed because black holes stimulate the emission of radiation in response to infalling matter. This stimulated radiation is non-thermal, and contains all of the information about the infalling matter, while Hawking radiation contains none of it.
Lenny Susskind writes in his book "The Black Hole War" that he proposed (in front of Sid Coleman and Stephen Hawking) that the problem would be solved if "the region just outside the horizon is occupied by a lot of tiny invisible Xerox machines" [6, p. 227]. But he then immediately retreated from this idea, because he thought it would violate the no-cloning theorem (Which we now know it does not). Susskind later revived the idea in his "black hole complementarity" proposal, claiming that somehow information would both fall into the black hole and be reflected at the horizon, but that the no-cloning theorem would not be violated because nobody would ever know (as you can't make an experiment both inside and outside of the black hole). This idea is based on a profound misunderstanding of quantum cloning, and in particular its relation to stimulated emission of radiation.
It’s a flu virus so deadly that scientists once halted research on the disease because governments feared it might be used by terrorists to stage a biological attack.
Yet despite the fact that the H5N1 avian influenza has killed 60% of the 650 humans known to be infected since it was identified in Hong Kong 17 years ago, the “bird flu” virus has yet to evolve a means of spreading easily among people.
Now Dutch researchers have found that the virus needs only five favorable gene mutations to become transmissible through coughing or sneezing, like regular flu viruses.
World health officials have long feared that the H5N1 virus will someday evolve a knack for airborne transmission, setting off a devastating pandemic. While the new study suggests the mutations needed are relatively few, it remains unclear whether they’re likely to happen outside the laboratory.
Scientists at Karlsruhe Institute of Technology (KIT) andEvonik Industries have developed a self-healing chemistry that allows for rapid healing of a plastic material using mild heating, restoring its initial molecular structure. It is based on a reversible chemical crosslinking reaction.
The reaction happens at temperatures from 50°C (122°F) to 120°C (248°F).
The material can be restored completely in less than 5 minutes, and is bound even more strongly than before.
Flowability is enhanced at higher temperatures, so the material can also be molded.
The self-healing properties can be transferred to a variety of plastics, including fiber-reinforced plastics components for automotive vehicles and aircraft.
Healing is also possible for material with scratches.
The research results were published in the journal Advanced Materials. Research partners were the Leibniz Institute of Polymer Research, Dresden, and the Australian National University, Canberra.
* The material uses a new low-temperature reversible system based on covalent chemistry, using “hetero Diels–Alder (HDA)” reactions via a new cyanodithioester compound with cyclopentadiene.
Bennu (the asteroid formerly known as “1999 RQ36”) is a time capsule from 4.5 billion years ago. A pristine, carbonaceous asteroid containing the original material from the solar nebula, from which our Solar System formed.
This is the first U.S. mission to return samples from an asteroid to Earth, addressing multiple NASA Solar System Exploration objectives to understand not just the origin of the Solar System, but the origin of water and organic material on Earth.
Key OSIRIS-REx science objectives include:
Return and analyze a sample
Create maps of the asteroid
Document the sample site
Measure the orbit deviation caused by non-gravitational forces
Compare observations at the asteroid to ground-based observations
The Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) will launch from Earth and travel for nearly two years to the asteroid Bennu. Upon arrival, OSIRIS-REx will map the total surface, creating a detailed shape model of the asteroid. OSIRIS-REx will also measure the magnitude of the Yarkovsky effect, a factor in the orbits of asteroids that may pose a threat to Earth. The craft will then approach — not land upon — Bennu, and extend a robotic arm to obtain a sample of pristine surface material (at least 60 grams or 2.1 ounces).
Returning to Earth in a Sample Return Capsule, a proven model originally used during the NASA Stardust mission, the material will then be studied by scientists at the NASA Johnson Space Center and from around the world for clues about the composition of the very early Solar System, the source of what may have made life possible on Earth. The data collected at the asteroid will aid our understanding of asteroids that pose an impact hazard to Earth, and the OSIRIS-REx spacecraft will be a pathfinder for future spacecraft that perform reconnaissance on any newly-discovered threatening objects.
Consider a pair of brothers, identical twins. One gets a job as an astronaut and rockets into space. The other gets a job as an astronaut, too, but on this occasion he decides to stay home. After a year in space, the traveling twin returns home and they reunite.
In March of 2015, NASA astronaut Scott Kelly will join cosmonaut Mikhail Kornienko on a one-year mission to the International Space Station. Their lengthy stay aims to explore the effects of long-term space flight on the human body.
The interesting thing about Scott is, he's a twin. His brother Mark is also an astronaut, now retired. While Scott, the test subject, spends one year circling Earth at 17,000 mph, Mark will remain behind as a control.
"We will be taking samples and making measurements of the twins before, during, and after the one-year mission," says Craig Kundrot of NASA's Human Research Program at the Johnson Space Center. "For the first time, we'll be able two individuals who are genetically identical."
NASA's study won't test the flow of time. The ISS would have to approach the speed of light for relativistic effects to kick in. Just about everything else is covered, though. NASA's Human Research Program recently announced the selection of 10 research proposals to study the twins' genetics, biochemistry, vision, cognition and much more.
A few examples to give the flavor of the research: "We already know that the human immune system changes in space. It's not as strong as it is on the ground," explains Kundrot. "In one of the experiments, Mark and Scott will be given identical flu vaccines, and we will study how their immune systems react."
Another experiment will look at telomeres—little molecular "caps" on the ends of human DNA. Here on Earth, the loss of telomeres has been linked to aging. In space, telomere loss could be accelerated by the action of cosmic rays. Comparing the twins' telomeres could tell researchers if space radiation is prematurely aging space travelers.
Meanwhile in the gut, says Kundrot, "there is a whole microbiome essential to human digestion. One of the experiments will study what space travel does to the inner bacteria which, by the way, outnumber human cells by 10-to-1."
Other proposals are equally fascinating. One seeks to discover why astronaut vision changes in space. "Sometimes, their old glasses from Earth don't work," notes Kundrot. Another will probe a phenomenon called "space fog"—a lack of alertness and slowing of mental gears reported by some astronauts in orbit.
"These will not be 10 individual studies," says Kundrot. "The real power comes in combining them to form an integrated picture of all levels from biomolecular to psychological. We'll be studying the entire astronaut."
Rescue bid launched to save Hainan gibbon from becoming first ape driven to extinction by humans.
China’s wildlife conservation efforts are under scrutiny as scientists battle to save a species found only in a tiny corner of an island in the South China Sea. The Hainan gibbon is the world’s rarest primate and its long-term survival is in jeopardy, according to an analysis.
Only 23 to 25 of the animals are thought to remain, clustered in less than 20 square kilometers of forest in China’s Hainan Island. The species (Nomascus hainanus), which numbered more than 2,000 in the late 1950s, has been devastated through the destruction of habitat from logging, and by poaching. Extinction would give the gibbon the unwelcome distinction of being the first ape to be wiped out because of human actions. To hammer out a plan to save it, international primate researchers convened an emergency summit in Hainan last month.
“With the right conservation management, it is still possible to conserve and recover the Hainan gibbon population,” says meeting co-chair Samuel Turvey, who studies animal extinctions at the Zoological Society of London (ZSL). “But given the current highly perilous state of the species, we cannot afford to wait any longer before initiating a more proactive and coordinated recovery programme.” He adds that the meeting was a successful first step towards saving the animal and that a plan of action is being finalized.
The plan will be based in part on a ‘population viability analysis’ that models the potential size of the gibbon population in coming decades for a range of different scenarios. It is being drawn up by Kathy Traylor Holzer, a conservation planner at the Conservation Breeding Specialist Group in Apple Valley, Minnesota. “It’s one of the smallest populations I’ve ever worked with,” says Traylor Holzer. “That number — in one place — is extremely scary.”
The lunar eclipses of 2014 are the first of four consecutive total lunar eclipses - a series known as a tetrad. During the 5000-year period from -1999 to +3000, there are 4378 penumbral eclipses (36.3%), 4207 partial lunar eclipses (34.9%) and 3479 total lunar eclipses (28.8%). Approximately 16.3% (568) of all total eclipses belong to one of the 142 tetrads occurring over this period (Espenak and Meeus, 2009). The mechanism causing tetrads involves the eccentricity of Earth's orbit in conjunction with the timing of eclipse seasons (Meeus, 2004).
During the present millennium, the first eclipse of every tetrad occurs sometime from February to July. In later millennia, the first eclipse date gradually falls later in the year because of precession.
Italian astronomer Giovanni Schiaparelli first pointed out that the frequency of tetrads is variable over time. He noticed that tetrads were relatively plentiful during one 300-year interval, while none occurred during the next 300 years. For example, there are no tetrads from 1582 to 1908, but 17 tetrads occur during the following 2 and 1/2 centuries from 1909 to 2156. The ~565-year period of the tetrad "seasons" is tied to the slowly decreasing eccentricity of Earth's orbit. Consequently, the tetrad period is gradually decreasing (Meeus, 2004). In the distant future when Earth's eccentricity is 0, tetrads will no longer be possible.
The umbral magnitudes of the total eclipses making up a tetrad are all relatively small. For the 300-year period 1901 to 2200, the largest umbral magnitude of a tetrad eclipse is 1.4251 on 1949 Apr 13. For comparison, some other total eclipses during this period are much deeper. Two examples are the total eclipses of 2000 Jul 16 and 2029 Jun 26 with umbral magnitudes of 1.7684 and 1.8436, respectively.
David Newman, a physicist at the University of Alaska, believes that smaller grids would reduce the likelihood of severe outages, such as the 2003 Northeast blackout that cut power to 50 million people in the United States and Canada for up to two days.
Newman and co-authors make their case in the journal Chaos. North America has three power grids that transmit electricity from hundreds of power plants to millions of consumers. Each grid is huge, because the more power plants and power lines in a grid, the better it can even out local variations in the supply and demand or respond if some part of the grid goes down.
But large grids are vulnerable to the rare but significant possibility of a grid-wide blackout like the one in 2003, when overloaded transmission lines hit unpruned foliage in Ohio, combined with a software bug a power-plant alarm system.
“The problem is that grids run close to the edge of their capacity because of economic pressures. Electric companies want to maximize profits, so they don’t invest in more equipment than they need,” Newman said.
In their new paper, the researchers ask whether the grid has an optimal size, one large enough to share power efficiently but small enough to prevent enormous blackouts.
The team based its analysis on the Western United States grid, which has more than 16,000 nodes. Nodes include generators, substations, and transformers, which convert high-voltage electricity into low-voltage power for homes and business.
The model started by comparing one 1,000-bus grid with ten 100-bus networks. It then assessed how well the grids shared electricity in response to virtual outages.
“We found that for the best tradeoff between providing backup power and blackout risk, the optimal size was 500 to 700 nodes,” Newman said.
The University of California, Berkeley, and UC San Francisco are launching the Innovative Genomics Initiative (IGI) to lead a revolution in genetic engineering based on a new technology already generating novel strategies for gene therapy and the genetic study of disease.
The Li Ka Shing Foundation has provided a $10 million gift to support the initiative, establishing the Li Ka Shing Center for Genomic Engineering and an affiliated faculty chair at UC Berkeley. The two universities also will provide $2 million in start-up funds.
At the core of the initiative is a revolutionary technology discovered two years ago at UC Berkeley by Jennifer A. Doudna, executive director of the initiative and the new faculty chair. The technology, precision "DNA scissors" referred to as CRISPR/Cas9, has exploded in popularity since it was first published in June 2012 and is at the heart of at least three start-ups and several heavily-attended international meetings. Scientists have referred to it as the "holy grail" of genetic engineering and a "jaw-dropping" breakthrough in the fight against genetic disease. In honor of her discovery and earlier work on RNA, Doudna received last month the Lurie Prize of the Foundation for the National Institutes of Health.
"Professor Doudna's breakthrough discovery in genomic editing is leading us into a new era of possibilities that we could have never before imagined," said Li Ka-shing, chairman of the Li Ka Shing Foundation. "It is a great privilege for my foundation to engage with two world-class public institutions to launch the Innovative Genomics Initiative in this quest for the holy grail to fight genetic diseases."
In the 18 months since the discovery of this technology was announced, more than 125 papers have been published based on the technique. Worldwide, researchers are using Cas9 to investigate the genetic roots of problems as diverse as sickle cell anemia, diabetes, cystic fibrosis, AIDS and depression in hopes of finding new drug targets. Others are adapting the technology to reengineer yeast to produce biofuels and wheat to resist pests and drought.
The new genomic engineering technology significantly cuts down the time it takes researchers to test new therapies. CRISPR/Cas 9 allows the creation in weeks rather than years of animal strains that mimic a human disease, allowing researchers to test new therapies. The technique also makes it quick and easy to knock out genes in human cells or in animals to determine their function, which will speed the identification of new drug targets for diseases.
"We now have a very easy, very fast and very efficient technique for rewriting the genome, which allows us to do experiments that have been impossible before," said Doudna, a professor of molecular and cell biology in the California Institute for Quantitative Biosciences (QB3) and an investigator in the Howard Hughes Medical Institute at UC Berkeley. "We are grateful to Mr. Li Ka-shing for his support of our initiative, which will propel ground-breaking advances in genomic engineering."