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Updated: 48 min 6 sec ago

Toronto newspaper found guilty of libeling climate scientist

10 February 2015

Ars Technica: In Canadian law, libel is defined as the publication of statements that are factually inaccurate and that damage "the plaintiff's reputation in the eyes of a reasonable person." A Canadian court has held that several pieces published by Toronto's National Post libeled climate scientist Andrew Weaver. The judge found that the paper misrepresented Weaver's statements and activities regarding climate change. As punishment, the Post will have to remove all the offending posts from its website and pay a fine of C$50 000 ($39 500). The paper avoided further penalty by removing the libelous reader comments.

Earth's center may be more complex than thought

10 February 2015
BBC: Earth’s inner core may have its own core, according to a new study published in Nature Geoscience. Xiaodong Song of the University of Illinois at Urbana-Champaign and colleagues used the seismic waves generated by earthquakes to look deep into Earth’s center. They found that the inner core, a Moon-sized sphere located some 5000 km below the surface, appears to have two distinct regions. They made that determination based on the orientation of iron crystals in relation to the polar axis: The crystals in the inner inner core are oriented east–west, while those in the outer inner core are oriented north–south. According to the researchers, that difference in alignment suggests something happened in Earth’s past to cause the inner core to rotate.

Quantum and classical processes combine to solve mazes

9 February 2015

MIT Technology Review: In cells, energy is rapidly transported through large, complex protein matrices with almost no energy loss. Filippo Caruso of the University of Florence in Italy and his colleagues have shown that the mechanism involved in energy transfer across these maze-like proteins likely combines quantum and classical effects. By themselves, both quantum and classical solutions to finding paths through mazes suffer from loss of energy. Caruso's team combined the simultaneous evaluation of multiple paths of the quantum process with the random jumps of the classical. The resulting hybrid process outperformed both individual ones. The researchers created various mazes from waveguides spaced at different distances from each other. When the waveguides were close together, light took full advantage of quantum effects; when further apart, classical noise disrupted the system. Thus the researchers were able to measure for the best mixing of quantum and classical properties. Their system still doesn't compare with the efficiency of the energy transfer in proteins, but it does provide some potential insight into the process.

Forest fires rerelease radiation from Chernobyl disaster

9 February 2015
New Scientist: Smoke from forest fires in Ukraine and Belarus has been spreading radioactive contaminants left over from the Chernobyl nuclear disaster. Following the reactor explosion in 1986, the surrounding area was evacuated and dense forest has since grown up. Radioactive cesium and other elements that settled in the soil are now being released into the air via smoke from the fires. According to a study by Nikolaos Evangeliou of the Norwegian Institute for Air Research and colleagues, global warming is exacerbating the problem. Increasing droughts are causing the number and intensity of the fires to increase. In addition, the radiation appears to be slowing the decomposition of the leaves littering the forest floor, which only serves to further fuel the fires. The lack of forest maintenance—for example, removal of dead trees and the clearing of roads—and the dearth of firefighting equipment and personnel are worsening the situation. The study’s findings could also be important for other areas that have suffered a nuclear disaster, such as Fukushima, Japan.

Brookhaven's new synchrotron is turned on

9 February 2015

Science: Last week US Secretary of Energy Ernest Moniz officially dedicated the $912 million successor to Brookhaven National Laboratory's National Synchrotron Light Source. Known as NSLS-II, the new facility will use a variety of wavelengths of light to study materials at a resolution nearing 10 nm and will reach intensities 10 000 times brighter than its predecessor. Currently only 7 of the 70 planned beamlines are operational; 25 more will be added over the next five years.

Val Logsdon Fitch

9 February 2015

Op-ed sees 2015 as possibly "the year we confirm both the virtues and the limits of general relativity"

6 February 2015
In the International New York Times, Philip Ball tells the world about coming tests of "probably the most beautiful of all existing theories."

Earth's ocean crust thickened during glacial periods

6 February 2015
Nature: During periods of extreme glaciation, so much water is sequestered in ice caps and glaciers that Earth's sea level drops by 100 meters. The corresponding reduction in over-pressure exerted by seawater on the crust below is significant enough that it facilitates the production of ocean crust. That's the conclusion reached by Richard Katz of Oxford University and his colleagues. The researchers investigated two areas of a mid-oceanic ridge, where new crust is created when magma wells up from the mantle below. The areas feature sequences of parallel hills whose separations imply that they formed at the maxima of the glacial cycles known as Milankovitch cycles. How exactly water pressure influences upwelling is unclear.

From planes to trains

6 February 2015
After World War II, Japan's best aeronautical engineers found work designing high-speed trains.

Andrew D. Hibbs

6 February 2015

Dark energy could influence individual galaxies

6 February 2015
New Scientist: To account for the observation that the expansion of the universe is accelerating, cosmologists have evoked a mysterious force called dark energy. Dark energy's influence is evident on cosmological scales, but could it also play out on galactic scales? Stephen Hsu of Michigan State University in East Lansing set out to answer that question—and discovered that the answer could be yes. For a large galaxy like the Milky Way, dark energy starts to outweigh gravity at distances beyond about 1.6 million light-years. At such a distance, dark energy would not be expected to shape the galaxy itself, but it could repel other, smaller galaxies, thereby explaining why the Milky Way has fewer satellite galaxies than theorists expect.

First stars not as old as we thought

6 February 2015
New Scientist: The first stars developed in the early universe about 150 million years later than previously estimated, according to a new analysis of data collected from Planck. The space-based telescope surveyed the cosmic microwave background from 2009 through 2012. Before the first stars formed, normal matter in the universe consisted of opaque clouds. Only when the starlight ionized those atoms did the universe become transparent. This latest analysis also confirmed Planck's previous measurements of the amount of ordinary matter, dark matter, and dark energy in the universe and continued to rule out the possibility of a ghostly particle called a sterile neutrino. The remaining mystery that Planck hasn't confirmed is the existence of primordial gravitational waves.

Smart electric grid could anticipate outages

6 February 2015
New York Times: New smart meters and sensors being installed by utility companies across the US may pinpoint outages almost in real time, even before customers call the electric company to complain. Most disruptions occur not along the main grid supply lines, nor at individual homes, but on the regional networks. A failure in one area will ripple through and can take multiple states out, at a cost of as much as $200 billion a year in lost economic activity, according to Edward H. Kennedy, CEO of Tollgrade, which supplies such equipment to utilities. The new sensors, about the size of a shoe box, send a detailed status message when the power goes down and can even predict when a failure might occur. The advance warning allows power companies to carry out some preemptive work to reduce the risk of an outage.

Obama's 2016 budget favors Mars 2020 rover and Europa mission

5 February 2015
Los Angeles Times: In its latest budget announcement, the White House has proposed to increase funding for NASA, from the $18 billion Congress adopted in 2015 to $18.5 billion in 2016. As a result, certain space science missions will see their budgets increase. Notable among them is the Mars 2020 rover, which is to get $228 million—more than twice what Congress allotted in 2015. However, although President Obama proposes to double his last year’s allocation, from $15 million in 2015 to $30 million in 2016, for a planned Europa mission, that amount pales in comparison with what Congress ultimately granted last year—$100 million. Left out in the cold is the Mars rover Opportunity, which has been roaming the surface of the red planet for more than a decade but would receive no funding under the White House budget.

Electric fields direct drugs to tumors

5 February 2015
Science: Chemotherapy targets cells that rapidly divide. In an adult cancer patient, those cells include the ones that make up tumors, but also ones in hair, bone marrow, the digestive tract, and the immune system. Given that most chemotherapy drugs are delivered intravenously, side effects are unavoidable and can be severe. To ensure that a higher fraction of a drug reaches its intended target, the tumor, Joseph DeSimone of the University of North Carolina, Chapel Hill, and his collaborators have been exploring the use of electric fields. The technique, which relies on the electrical polarity of most drug molecules, has been applied before to drive drugs to the eye and bladder. DeSimone set out to test whether it could also work with solid tumors. He and his team created small reservoirs of drugs, equipped them with an electrode, and then implanted them next to tumors (the team used mice and dogs in their experiments). Oppositely charged electrodes were placed on the other side of the tumors. The results are promising. Compared with delivering the drug intravenously, the use of electric fields not only significantly boosted the concentration of the drug in the tumor, but also shrank the tumor faster. Whether the technique could work with humans remains to be seen.

New steel alloy could lead to lighter-weight cars

5 February 2015
Nature: Steel, an alloy of mostly iron and carbon, has long been the main material for car bodies. With the push to improve fuel efficiency, however, auto manufacturers would like to find a lighter material that would be just as strong and easy to work. Now Sang-Heon Kim and colleagues at Pohang University of Science and Technology in South Korea say they have developed an improved alloy by introducing nickel to a high-aluminum, low-density steel. The nickel causes nanometer-sized particles of B2, a steel structure known for its hardness, to form and disperse throughout a more ductile form of steel called austenite. The combination is ultrastrong, lightweight, and highly pliable. The researchers hope to see their new alloy put to the test at one of the world’s largest steel manufacturers, POSCO, in South Korea.

Longer-lasting lithium-ion battery for cell phones

5 February 2015
MIT Technology Review: To power portable electronic devices to last twice as long between charges, a company called SolidEnergy is developing a new lithium-ion battery. Among its innovations is an ultrathin metal anode composed of lithium-metal foil on copper and a combination solid and liquid electrolyte. The lithium increases the battery’s storage capacity, and the high-efficiency electrolyte inhibits the lithium’s ability to react with it, which improves the flow of electrical current. The battery is nonflammable and nonvolatile, works at room temperature, can be recharged up to 300 times while retaining 80% of its storage capacity, and can be manufactured with existing battery production processes.

Last year’s evidence for primordial gravitational waves negated

5 February 2015
Dust seems to be the cause of the microwave polarizations that generated so much excitement about cosmological inflation.

Russians enter Lake Vostok again

4 February 2015
New Scientist: Lake Vostok, an isolated lake nearly 4 km below the Antarctic ice, has remained relatively undisturbed for 15 million years. In 2012 a Russian team led by Vladimir Lipenkov of the Arctic and Antarctic Research Institute and Nikolay Vasiliev of the  National Mineral Resources University broke into the lake and collected water samples that they later claimed contained DNA from an unknown bacterial species. However, the samples were contaminated when the team withdrew the drill bit too quickly from the borehole and water from the lake and fluid from the drill mixed together. A second attempt, using the same borehole most of the way, reached the lake surface at 5:12pm on 25 January. Now that they know the lake's pressure and depth, the team should be able to withdraw the drill at the right speed without contaminating the sample. 

How gold formed in the Vaal Reef deposit

4 February 2015
Arstechnica: The Vaal Reef deposit, which formed 3 billion years ago in South Africa's Witwatersrand basin, is one of the best gold deposits in the world. How the gold got there is uncertain, and the geological evidence is contradictory. In Nature Geoscience, ETH Zürich geologist Christoph Heinrich suggests a scenario that seems to fit all the observations. His hypothesis centers on the voluminous eruptions of acidic volcanic gases such as sulfur dioxide and the low oxygen environment that prevailed on Earth at the time. When the gases dissolved in rainwater and then entered rivers, the SO2 formed a low oxygenated sulfuric acid and dissolved the gold out of the volcanic rock. Downstream, the gold-laden water encountered mats of living microbes, dead organic matter, or methane, which chemically reacted with the compound and precipitated out the gold.

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