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Updated: 1 hour 23 min ago

Computer software verifies mathematical fruit-stacking proof

12 August 2014

New Scientist: Finding the best way to stack oranges or other spherical fruit has perplexed grocers for centuries. Four hundred years ago Johannes Kepler proposed a pyramid shape, but couldn’t prove it mathematically. In 1998 mathematician Thomas Hales devised a proof so complex it took 12 reviewers four years to check. Even then they were not 100% certain. So Hales initiated the Flyspeck project—a method of using a computer to check a mathematical proof. With the use of two so-called formal proof software assistants—Isabelle and HOL Light—Hales’s team verified the proof by translating the mathematics into computerized form and letting the computer do the bulk of the calculations. Hales hopes that such formal proofs will not only speed up the process but also provide a much higher degree of certification than is possible with human peer review.

Keystone XL oil pipeline could increase pollution more than thought

11 August 2014

Nature: According to a recent study, the proposed Keystone XL oil pipeline could result in four times the carbon emissions estimated by the US State Department. The researchers say the government study did not take into account the fact that the pipeline would lead to an increase in oil production, which would cause global prices to drop and global use to rise. As a result, global greenhouse gas emissions could increase by as much as 110 million tons per year, compared with the 27 million tons estimated by the US State Department. At least one critic of the proposed pipeline says that economics aside, the project should be canceled to discourage the building of other similarly polluting projects.

Chile earthquake fractured ice in Antarctica

11 August 2014

Science: A magnitude 8.8 earthquake that struck off the coast of Chile in 2010 also produced “icequakes” in Antarctica. According to a study published by Zhigang Peng of Georgia Tech and colleagues, their investigation of surface waves generated by the large quake turned up evidence of tiny seismic signals, associated with ice cracking, in Antarctica. Of the two types of surface waves generated by earthquakes, only the Rayleigh waves appeared to have any effect in Antarctica. “That makes us suspect that the mechanisms of icequakes might be different from regular earthquakes,” said Peng. Next they plan to look at data collected at all the Antarctic stations over the past four to five years for the effects of other large geologic events.

Tornado season becoming more intense

11 August 2014

New Scientist: Although the number of tornadoes per year in the US has not increased over the past several decades, more tornadoes are occurring on a given day than ever before. James Elsner of Florida State University and colleagues report that since 2001 there has been at least one day per year when 32 or more tornadoes struck, and in 2011 there were six such days. Before 1980 it was rare to have as many as 16 in a day. The reason may be due to global warming, which is causing both Earth’s surface and upper atmosphere to heat up. Tornadoes form when cold air in the upper atmosphere allows warm air near the surface to quickly rise. With fewer periods of cold air high up, there are fewer opportunities for warm surface air to escape. But when it does, it “goes crazy,” says Elsner. Such shifts in atmospheric temperature may also be influencing other weather systems, such as hurricanes and rainstorms.

An elementary particle collision never before observed

11 August 2014
The scattering of vector bosons offers a new way to test the reigning paradigm of particle physics.

IBM's new chip works like a brain

8 August 2014
New York Times: In a paper published yesterday in Science, a team from IBM and Cornell University describes a new computer chip whose architecture is modeled on the human brain. The chip contains 5.4 billion transistors organized into 4096 cores. The cores in turn are connected to each other in a network that integrates 1 million neuron analogues and 256 million synapse analogues. Both the neurons and synapses are reconfigurable. When it comes to number crunching, the brain chip is no match for conventional chips. However, its parallel architecture requires less power and is suited to tasks, such as pattern recognition, that artificial neural networks perform.

Beijing coal ban could spell end of global boom

8 August 2014

New Scientist: The city of Beijing has decided to ban coal burning by 2020, and China plans to prohibit the construction of new coal-fired power plants there and in several other cities. Air pollution has become increasingly severe in Beijing, due not only to coal burning but also to vehicle emissions and dust storms. To compensate for the loss of coal as an energy source, the Chinese government is investing instead in renewables and nuclear power and is promoting energy efficiency measures. Because China accounts for half the world’s coal consumption, the proposed ban could signal the end of the global boom in coal production.

Microbial life discovered in water droplets in oil

8 August 2014

Nature: Microorganisms and bacteria have been found living in tiny water droplets suspended in the largest natural asphalt lake in the world—Pitch Lake on the island of Trinidad. In a study published today in Science, researchers used nuclear magnetic resonance and mass spectrometry to examine the complex microbial communities, which were seen to be eating and processing the oil. Their findings indicate a possible strategy for oil companies to reduce biodegradation of oil reservoirs by eliminating the formation of such microdroplets. But companies might also be able to use the droplets to clean up oil spills underground where pipelines have burst. In addition, the microorganisms’ ability to thrive in such inhospitable environments has led the researchers to propose that similar life forms could exist on other worlds, such as beneath the hydrocarbon lakes of Saturn’s moon Titan.

A quiet revolution

8 August 2014
The 1970s were a time of economic woe, political turmoil, and flourishing particle physics.

UK research station in Antarctica loses power

8 August 2014

BBC: On 30 July the Halley VI Research Station, run by the British Antarctic Survey (BAS), lost power for 19 hours. The station is located on the Brunt Ice Shelf, which floats on the Weddell Sea and where outdoor temperatures during Antarctic winter can go as low as –32 °C. Although power and some heating are back on line, the station has not yet returned to normal operation. The BAS reports that all staff are currently safe and in good health. The cause of the power loss has not yet been determined.

Funding cuts threaten Australia’s leadership in Antarctic science

7 August 2014

Sydney Morning Herald: A group of Australian scientists has warned that recent cuts to budgets and science programs could adversely affect the country’s leadership in Antarctic research. The cuts are particularly ill-timed because of Antarctica’s growing importance in the study of climate change. The continent comprises one-tenth of Earth’s land surface, nearly 90% of Earth’s ice, and 70% of its fresh water, according to a Nature article in which leading scientists outline the six most pressing priorities for Antarctic science. One of the scientists, Steven Chown of Monash University, has emphasized the need for increasing international collaboration and funding to ensure against gaps in long-running research and loss of key researchers in the field. He also points out that “science leadership in the region is the key to political influence” and, hence, to determining whether Antarctica's future will focus on environmental stewardship or resource exploitation.

Bipartisan support for US science more likely in Senate than House

7 August 2014

Science: The US House of Representatives has been criticized for its recent science bill, but the one introduced in the Senate looks more promising to science advocates. The House’s Frontiers in Innovation, Research, Science, and Technology Act of 2014 passed in May after a year-long battle, during which House Republicans rejected all 13 of the Democrats’ proposed amendments. The bill, which sets policy for NSF and NIST, would severely cut NSF’s funding of research in the social, behavioral, and economic sciences. In contrast, the Senate’s America COMPETES Reauthorization Act of 2014, introduced by John “Jay” Rockefeller (D-WV), calls for “robust” funding increases for both NSF and NIST. In addition, Senate Republicans, led by John Thune (R-SD), appear more willing to compromise. The Senate science panel is expected to address the bill next month.

Comparisons with language could help simplify chemical analyses

7 August 2014

New Scientist: A recent study applies the concept of pattern recognition used in computational linguistics to research on key molecular structures in organic chemistry. Bartosz Grzybowski of Northwestern University in Evanston, Illinois, and his colleagues treated molecules as sentences and molecular fragments as words. They then developed an algorithm to find fragments that are common among different molecules and rank their frequency. They also looked for the fragments with the highest information content. What they found was that the bonds connecting the most informative molecular fragments were often key bonds that connect simpler compounds and serve as building blocks for more complex molecules. Although the parallels between chemistry and language are not clear-cut, the tools the researchers have developed could prove useful in picking out unique chemical fragments that might be missed by human researchers and that could be used in the development of new compounds and pharmaceuticals.

Mercury pollution threatens world’s oceans

7 August 2014

Nature: Mercury levels in the upper ocean have tripled since the beginning of the Industrial Revolution, according to a study published in Nature. Because of mercury’s unique properties, it has come to be used in applications from fossil-fuel electrical power plants to laboratory equipment to cosmetics. However, mercury is highly toxic, and as it leaks into the air and onto the land, it eventually ends up in the oceans, where it can make its way into the food chain. To try to determine how marine mercury pollution levels have changed over time, the researchers collected thousands of water samples from the Atlantic and Pacific Oceans. Because surface water has been more recently exposed to mercury pollution than water deeper down, samples of different depths were compared. However, the researchers found that despite the disturbing rise in mercury pollution, the oceans are not uniformly contaminated. That leads them to believe that efforts to reduce mercury pollution could be effective.

Open-access advocates find Energy Department plan "vague and disappointing"

7 August 2014
Nature, Science, and the Washington Post report reactions to the first major development under a 2013 White House directive.

How a river transports sediment

7 August 2014
Mercury that leaked from a textile mill into a river decades ago served as a serendipitous tracer.

Construction to begin on unique ground-based telescope

6 August 2014

Science: Now that NSF has released the first installment of construction funding, work on building the Large Synoptic Survey Telescope in Chile is about to begin. The telescope is notable for its unusual design: It will have three mirrors instead of the usual two. The result will be a very wide field of view, which will allow the telescope to photograph the entire sky every few nights. Among the project's goals are the detection of faint astronomical objects, transient optical events such as supernovae, and evidence of possible dark matter and dark energy. One of the biggest challenges will be how to manage the large volume of data the telescope will produce once it begins operating around the year 2020.

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.