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Updated: 1 hour 33 min ago

Temporary cooling of Earth’s climate may be due to volcano

6 August 2014

Ars Technica: Despite global warming, global temperatures continue to exhibit sporadic dips. To better understand the year-to-year variability in global surface temperature, a group of researchers developed a series of climate model experiments that looked at the complex relationship between the Atlantic and Pacific Oceans, the trade winds that blow between them, and their impact on the atmosphere. Despite the model's complexity, the experiments failed to completely explain the most recent bout of lower-than-average global surface temperatures. According to the researchers, some other factor must be contributing. They point to a volcanic eruption in the Philippines that occurred more than two decades ago: Not only did it lower temperatures for several years immediately following the event, it may have caused widespread climate perturbations that are still being felt today.

Database of open-access journals tightens its quality control

6 August 2014

Nature: Set up in 2003 to provide a definitive database of open-access scholarly publications, the Directory of Open Access Journals (DOAJ) has grown to comprise some 10 000 listings. However, because of complaints that some of the journals exercise questionable practices, such as providing minimal peer review, the DOAJ has decided to introduce stricter standards. To weed out the substandard journals, all publishers have been asked to reapply for listing on the DOAJ website. The new application form requests more detailed information about each journal, including specifics concerning the quality and transparency of its editorial process, its digital archiving policy, and its content licensing. DOAJ founder Lars Bjørnshauge hopes that the reapplication process will create one of the largest “whitelists” of acceptable open-access journals.

<em>Rosetta</em> spacecraft arrives at comet

6 August 2014

New York Times: Earlier today the European Space Agency’s Rosetta probe became the first ever to enter into orbit around a comet. Its arrival marked the end of a 10-year, 6-billion-kilometer odyssey to connect with comet 67P/Churyumov–Gerasimenko. The trip included three flybys of Earth and one of Mars, which served as gravitational slingshots to get Rosetta up to speed and put it on the same orbital path as the comet. Now the probe can begin a yearlong observation period, during which time the comet is expected to make its nearest approach to the Sun. During that time, 67P/C–G should heat up and grow the long tail of water vapor and dust that is characteristic of comets. In November, to get an even closer look at that transition, Rosetta will launch a small lander that will attach itself to the comet’s surface.

The alternative career is no longer alternative

6 August 2014
It’s time to rethink STEM graduate education and align it with the real job market.

Damaged robot can adapt and keep going

5 August 2014

BBC: A new robot design uses a trial-and-error algorithm to diagnose problems and find a way for the robot to keep operating. The algorithm was modeled on the behavior of injured animals, which have been known to adapt to a wide variety of injuries. Unlike current robot designs, which rely on a limited number of fixes preprogrammed into their system, the new design can handle unforeseen problems by allowing robots "to creatively discover compensatory behaviors,” say the researchers in their paper published on the arXiv website. Their prototype robot was successful in learning to adjust after having one of its six legs broken, and it did so in just two minutes. Such a self-learning robot could be useful in situations where humans can’t go, such as certain space missions, search and rescue operations, and disaster response.

Beware zombies, haters, pigs, and jerks

5 August 2014
How to recognize, cope with, and escape from various types of toxic coworkers.

Binaries bend planetary disks

5 August 2014
Ars Technica: As giant molecular clouds collapse and shrink, they form stars. In the process, the clouds have to shed angular momentum. More often than not, they do so by breaking up to form two stars that orbit their mutual center of mass. And if either of those stars goes on to form a planetary system, the planets' orbital planes will tend to align with that of the two stars. Rachel Akeson of Caltech and Eric Jensen of Swarthmore College have found that one binary system, HK Tauri, does not fit the alignment paradigm. Both stars in the system have protoplanetary disks. Using the Atacama Large Millimeter/Submillimeter Array to observe the stars in the far-IR, Akeson and Jensen have determined that the two disks are tilted by 60° to 68° with respect to each other. Although their measurement is relative, not absolute, the astronomers can nevertheless conclude that at least one of the protoplanetary disks is misaligned with respect to the binary system's orbital plane. The discovery suggests that planetary orbits can be modified while the planetary system is forming.

Navier–Stokes equations remain elusive

5 August 2014

Nature: A set of equations devised to explain the motion of fluids continue to confound mathematicians. First proposed in the 19th century by a French engineer and an Irish mathematician–physicist, the Navier–Stokes equations have been used to model the weather, ocean currents, and air flow around airplane wings. Despite the equations' evident success in describing turbulent systems, no one has proven that solutions in three dimensions can always be found and are always finite. Because of their importance, the Navier–Stokes equations were established as one of the seven Millennium Prize Problems in 2000 by the Clay Mathematics Institute of Cambridge, Massachusetts. Although two mathematicians—Penny Smith of Lehigh University in Pennsylvania and Mukhtarbay Otelbaev of the Eurasian National University in Kazakhstan—have each claimed to have cracked the problem, both proofs have been found to contain errors. Only one of the Millennium Prize problems has been solved so far: the Poincaré conjecture by Grigory Perelman in 2002.

Recovering speech from vibrations of a potato-chip bag

5 August 2014

Washington Post: Video footage of a potato-chip bag, the surface of a liquid in a glass, or the leaves of a potted plant can reveal what is being said by people speaking nearby. As people talk, the sound waves strike objects in the vicinity and cause them to vibrate. Researchers at MIT have been working to capture those tiny vibrations on film and, through the use of an algorithm, convert them to an audio signal. Interestingly, an ordinary digital camera can be used because of a design quirk called rolling shutter, which captures scenes by recording visual information one row of photodetectors at a time and assembling the rows into a single image, rather than taking a snapshot of the entire scene at once. “It kind of turns a two-dimensional low-speed camera into a one-dimensional high-speed camera,” says Abe Davis, coauthor of the group’s paper, which will be presented at this year’s Siggraph computer graphics conference.

Walking a silicon atom through a graphene landscape

4 August 2014
An atom-scale imaging technique finds another role as an atom-scale manipulator.

Mathematical model explores evolution through correlated novelties

4 August 2014

Washington Post: The evolution of any system, whether it is biological, physical, or conceptual, involves a series of discoveries or innovations, each building on the ones that preceded it. To explain the phenomenon, Steven Strogatz of Cornell University and colleagues cite Pólya’s urn, in which a certain number of white and black balls are placed. When one ball is drawn out, its color is noted; then it is replaced and another ball of the same color is added to the urn. Thus as one color is selected, the odds increase that it will be picked again. That self-reinforcing property, called “the adjacent possible,” can be seen in everything from the evolution of feathers and flight in birds to the selection of songs in online music catalogs. The researchers discuss the “dynamics of correlated novelties” in greater depth in their recent study published in Scientific Reports.

Watson supercomputer may soon participate in business meetings

4 August 2014

MIT Technology Review: Researchers at IBM are fine-tuning the Watson supercomputer to be able to listen in on business meetings and weigh in on decisions. According to IBM, Watson is a next-generation artificially intelligent machine that can understand human speech, make decisions based on available data, and learn as it goes. Watson has already demonstrated its cognitive technology when it successfully competed in 2012 against two human players on the TV show Jeopardy! In a recent demonstration, IBM researchers tested Watson’s business acumen by enlisting its help in creating a short list of companies to acquire. Watson helped winnow down the list through its analysis of both written information and the researchers’ verbal discussion. Watson could also serve a number of other functions, including monitoring people’s contributions to the discussion and fact-checking assertions.

Some PR companies refuse to work for climate deniers

4 August 2014

Guardian: In April both the Guardian and the Washington-based Climate Investigations Center independently surveyed the world’s top 25 public relations firms regarding their views on global warming. Ten of them said they would not represent clients who deny anthropogenic climate change. Among those companies are WPP, Waggener Edstrom Worldwide, Weber Shandwick, Text100, and Finn Partners. Because PR firms are responsible for spreading information and trying to influence public opinion, they have played a key role in the climate change debate. However, many of the firms appear to prefer to remain neutral on such issues, as evidenced by the fact that a majority did not respond to the surveys, regardless of whether or not they had taken on clients promoting action on climate change.

Mars spacecraft take cover from comet dust

4 August 2014

Los Angeles Times: As Comet Siding Spring, or C/2013 A1, goes hurtling past Mars in October, scientists are worried about the safety of spacecraft flying in its vicinity. The comet itself poses no threat; rather, the danger lies in the comet’s tail, which is made up of a stream of tiny dust particles zipping along at more than 55 km/s, like tiny cannonballs or bullets. To protect the three spacecraft orbiting Mars—the Mars Reconnaissance Orbiter, Odyssey, and MAVEN—engineers are adjusting the crafts’ speed so that they will end up on the opposite side of Mars as the comet passes. By using Mars as a shield, the spacecraft should be able to avoid contact with the bulk of the comet’s dust particles.

Algorithm developed to predict Supreme Court decisions

1 August 2014

Ars Technica: A new algorithm can predict the voting behavior of the US Supreme Court with roughly 70% accuracy, according to a study published on the Social Science Research Network. “Our model has proven consistently accurate at predicting six decades of behavior of thirty Justices appointed by thirteen Presidents,” says one of the developers, Josh Blackman, on his blog. The algorithm uses the extremely randomized trees method to weight some 90 variables, including decisions in individual cases and background information on the justices and the court. The algorithm will be tested against humans in an upcoming tournament, in which it will be pitted against the players of Blackman’s FantasySCOTUS.

Tesla and Panasonic to build battery factory in US

1 August 2014

New York Times: Tesla Motors and Panasonic are collaborating on a factory to be built in the US to produce lithium ion batteries for Tesla’s all-electric vehicles. The battery is what makes an all-electric vehicle so much more expensive than a gas-powered one, so the collaboration is designed to cut costs by streamlining the manufacturing process and through economies of scale. "Not only does the Gigafactory enable capacity needed for the Model 3 [car] but it sets the path for a dramatic reduction in the cost of energy storage across a broad range of applications,” said J. B. Straubel, Tesla’s chief technical officer, in a press release. The site of the Gigafactory has not yet been decided.

Release of methane gas could explain mysterious Siberian crater

1 August 2014
Nature: Last month a helicopter pilot spotted a wide, deep, circular crater as he flew over the Yamal Peninsula on Siberia's north coast. The crater's unusual size and shape prompted speculations that it might have formed as the result of a meteorite or missile hit. After visiting the crater, archeologist Andrei Plekhanov of Russia's Scientific Center of Arctic Studies has concluded that the release of methane from thawing permafrost was the culprit. Plekhanov found that the concentration of methane at the bottom of the crater was five orders of magnitude higher than the typical ambient value. At the crater's latitude, subsurface methane is usually frozen in the form of methane clathrate, which consists of methane molecules locked inside cages of water ice. According to Plekhanov, rising temperatures melted the clathrate and freed the methane, which turned to gas and exerted enough pressure to blow open the crater.

NASA picks the scientific payload of its next Mars rover

1 August 2014
BBC: At a press conference held yesterday in Washington, DC, NASA official and former astronaut John Grunsfeld announced the seven scientific instruments that would be carried on the agency's next Mars rover. Provisionally named Mars 2020 for its scheduled launch date, the rover will be based on the Curiosity rover, which is currently exploring the red planet's Gale Crater. Like its forebear, Mars 2020 will carry cameras, spectrometers, and meteorological sensors. But its payload will also include the Mars Oxygen ISRU Experiment, which will produce oxygen from carbon dioxide in the Martian atmosphere. In future missions, locally produced oxygen could help power a return trip to Earth and sustain human explorers.

Physics at San Diego Comic-Con International IV

1 August 2014
The annual celebration of popular culture features superheroes, anime characters, zombies—and physics.

A deep earthquake goes supershear

31 July 2014
Seismic analysis of an earthquake off Russia's Kamchatka Peninsula last year offers evidence that deep earthquakes are more complicated than geoscientists realized.

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