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Updated: 22 hours 58 min ago

Ants contribute to carbon sequestration

4 September 2014

Ars Technica: The weathering of minerals on Earth’s surface helps regulate its climate over geological time scales. As the minerals break down, they react with carbon dioxide. In warmer regions, the minerals break down more quickly, resulting in more CO2 being sequestered, which has a cooling effect. In cooler regions, the minerals break down more slowly and less CO2 is sequestered, which has a warming effect. Other factors are known to contribute to such physical weathering, including the breaking up of rocks and soil by tree roots, lichens and fungi, and burrowing organisms. To try and determine to what degree biology influences the process, Ronald Dorn of Arizona State University conducted a 25-year-long study of the weathering of basalt sand samples placed in a variety of environments, from Arizona to Texas. He put the samples in holes augured into the ground, tree roots, ant nests, and other locations. When he compared the samples, the material in the ant nests showed the most weathering, with 50–175 times that of the baseline sand. How the ants cause such accelerated weathering is unknown, but understanding the chemistry involved might one day help humans in their efforts to reduce atmospheric carbon levels.

Smart chopsticks can assess food safety

4 September 2014

Guardian: China has suffered a number of food scandals in recent years—from toxic milk to glow-in-the-dark pork to recycled cooking oil. To determine whether food is safe to eat, a set of “smart” chopsticks has been developed. When linked with a smartphone app, they can indicate the levels of freshness, contamination, and nutrition of the food they touch. The product is the brainchild of Baidu, the Chinese version of the search-engine giant Google. Although the chopsticks were demonstrated at the company’s recent technology innovation conference in Beijing, they are not yet ready for mass production.

Latest climate models predict weak-to-moderate El Niño this year

3 September 2014

Nature: Because of the hint of an impending El Niño in January, researchers are watching the Pacific Ocean closely for any changes in temperature and atmospheric conditions. Extreme El Niño events, such as those that occurred in 1982–83 and 1997–98, can severely disrupt global weather patterns. The 1997 event, one of the strongest on record, “caused extreme rainfall along the western coasts of North and South America and drought in Australia and southeast Asia, resulting in thousands of deaths and tens of billions of dollars’ worth of damage,” writes Mark Zastrow for Nature. For that reason, scientists are using satellites, buoys, and autonomous underwater vehicles to gather as much information as possible on the impending event. Not only do they hope to be able to improve their forecasting of future El Niño events, but they also want to better understand El Niño’s history going back thousands of years.

JAXA reveals asteroid sample collector <em>Hayabusa 2</em>

3 September 2014

Japan Times: Last weekend the Japanese Aerospace Exploration Agency (JAXA) revealed its Hayabusa 2 spacecraft. As the name suggests, it is a follow-up to JAXA's Hayabusa, which returned to Earth in 2010 after completing a seven-year mission to collect samples from the asteroid Itokawa. Hayabusa 2 will target asteroid 1999 JU3, which contains both carbon and water. JAXA hopes that the samples it collects will provide clues to the origin of life and the formation of the solar system. The agency plans to launch the spacecraft later this year.

Phase-change material used to create single bits that act as multiple logic gates

3 September 2014

Ars Technica: Phase-change materials take on different physical structures depending on the speed at which they are cooled. They are amorphous with a high electrical resistance when quickly cooled, and regular with low resistance when slowly cooled. The materials have been used to create computer memory bits, and last year they were combined with resistors to form logic gates. Now a group of researchers has created a single phase-change memory bit that can act as multiple logic gates. To do that, they provide a low level of heating to the hardware, which makes flipping the bit easier. Then they use pulses of low heat and high heat, representing 0 and 1 respectively, to affect how the bit functions. A single pulse causes the bit to behave as an OR gate, and combinations of pulses can cause it to behave as a NOR or NAND. The low-level heating increased the speed at which the bit switches states to nearly the same speed as modern processors. It is not yet clear whether having a single bit perform multiple gate functions will be useful, but the development is an important proof-of-concept step for phase-change materials in computing.

Learning to teach inquiry-based science

3 September 2014
How China's National Teacher Training Project is boosting the skills and effectiveness of the country's science educators.

Booming economy threatens language diversity

3 September 2014

BBC: Many of the world’s languages are disappearing, particularly in regions with high economic growth, according to a recent paper published in the Proceedings of the Royal Society B. Environmental factors have long played a role in shaping language diversity. However, now it seems that because of accelerating economic development in certain parts of the world, minority languages are giving way and a single, national language is taking over. Tatsuya Amano of the University of Cambridge and colleagues say most at risk are minority languages in North America, Europe, and Australia. The tropics and the Himalayas, home to many small-population languages, may also face similar problems as rapid economic growth commences in those areas. The researchers hope to call attention to the phenomenon in order to better promote and direct efforts to prevent this cultural loss.

World Anti-Doping Agency bans gases but can't test for them

2 September 2014
BBC: Some reports suggest that regimens of inhaling xenon or argon mixed with oxygen can increase the body's production of the protein hypoxia inducible factor 1 (HIF1). An increase in HIF1 creates more erythropoietin (EPO), which increases the number of red blood cells in the body and, hence, its oxygen efficiency. As a result, some athletes have adopted use of the gases in an effort to improve their performances. Now, the World Anti-Doping Agency (WADA), which governs many sports, has added both xenon and argon to its list of prohibited substances. However, there are no effective tests for whether an athlete has been using the gases. Why the gases have been banned when similar regimens, such as hypoxic chambers and oxygen tents, are still allowed has been questioned by some sports medicine experts.

A passion for asteroids

2 September 2014
Atmospheric nuclear tests can reveal a lot about exploding asteroids.

Opportunity rover and <em>Lunar Reconnaissance Orbiter</em> get two more years of life

2 September 2014
Nature: A review and prioritization of NASA's planetary science missions is expected to be released tomorrow. Two of the missions that were thought to be under threat of cancellation appear to have been granted two more years of operation: the Martian rover Opportunity and the Lunar Reconnaissance Orbiter (LRO). Opportunity, which has been suffering from a variety of mechanical problems, has been operating for 10 years and has traveled more than 40 km on the surface of Mars. LRO completed its primary task of mapping potential landing spots for astronauts in 2010 and has been imaging recent meteorite impacts. Also under review, but not considered likely to have their funding cut, are the Martian rover Curiosity and the Saturn-orbiting Cassini. Still unknown are the fates of the Mars Reconnaissance Orbiter, the Mars Odyssey orbiter, and an instrument onboard the European Space Agency's Mars Express.

EPA seeks to lower US ozone limit

2 September 2014

Los Angeles Times: The US Environmental Protection Agency is proposing to reduce the federal standard for ground-level ozone. The EPA is required by the Clean Air Act to review the standard every five years. California, which has 16 areas that don’t meet the current ozone limit, will be particularly hard pressed if it is lowered. "We're going to need to have zero or near-zero emissions across the entire economy,” said Sam Atwood, a spokesman for the South Coast Air Quality Management District. Although industry representatives and Republican members of Congress insist that lowering the environmental limit will damage the economy, Janice Nolen, assistant vice president of national policy at the American Lung Association, claims just the opposite: “Since the 1970s, we've reduced major air pollutants by 70% and the economy has more than doubled."

Earth's plate tectonics speeding up, says study

2 September 2014

New Scientist: According to a recent paper published in Precambrian Research, both the average rate of continental collisions and the average speed with which the continents change latitude have doubled over the past 2 billion years. Kent Condie of the New Mexico Institute of Mining and Technology and colleagues based their findings on two sets of data: the timing and locations of mountain-range formation and average plate velocities based on magnetic data from volcanic rocks. The researchers think the acceleration may be due to the amount of water in Earth’s mantle, which has recently been found to be much vaster than previously thought. As a result, the mantle may becoming runnier, which could speed up the rock flow. However, the work is considered controversial because it contradicts a previous study that says plate motion has been slowing for the past 1.2 billion years due to the cooling of Earth’s core and mantle.

Thomas Fields

2 September 2014

<em>Washington Post</em> calls for aggressive, US-led international climate action

2 September 2014
A series of editorials endorses emissions caps with permit sales and citizen rebates.

TNT-covered carbon nanotube fibers generate electricity when burned

29 August 2014
MIT Technology Review: Four years ago, Michael Strano of MIT and his colleagues created yarn out of carbon nanotubes that were covered in TNT. When ignited with a laser, the fibers burned like fuses, but with the curious effect of generating an electrical current. Strano's team has now discovered that the combustion creates a wave of electrons that travels down the fiber. Thanks to the discovery, they could increase the yarn's electricity-generating efficiency by a factor of 10 000, with the potential for further increases. The actual efficiency is still very low compared with that of traditional combustion generators, but Strano believes the material could find use in applications that need short bursts of electricity. With further advances, large versions of the generators could be used to power electric motors with liquid fuels.

Theory of origin for Type Ia supernovae gains direct evidence

29 August 2014

BBCType Ia supernovae have long been thought to be caused when a white dwarf gains enough mass to push it over the Chandrasekhar limit. White dwarfs are the remains of stars that have burned through most of their light elements and have a core of carbon and oxygen that is no longer undergoing fusion. If they steal enough material from a companion star, or merge with another white dwarf, the extra mass compresses the core and causes the heavier elements there to fuse. The sudden release of energy causes the star to explode into a supernova. Although the theory has been widely accepted for decades, a supernova detected on 21 January 2014 has provided the first confirmation that a white dwarf is the source of type Ia supernovae. When a white dwarf’s carbon and oxygen fuse, they create a radioactive isotope of nickel that decays into radioactive cobalt that then decays to stable iron. Observations of the supernova using the European Space Agency’s INTEGRAL spacecraft revealed the signature gamma-ray emissions associated with the cobalt isotope’s decay. The emissions also closely matched the model of a white dwarf explosion. However, there is still not enough information to determine whether it was a white dwarf drawing material from a companion or a collision of two white dwarfs that caused the supernova.

Fermilab builds holometer to look for jitter in spacetime

29 August 2014

New Scientist: To probe space and time at the very smallest scales, researchers at Fermilab have built a holographic interferometer, or holometer. At the quantum level, matter and energy behave more like waves than particles. The researchers propose that a similar concept may apply to space and time. Their device consists of two 40-meter-long tubes fitted with mirrors through which they shine powerful lasers. If both sets of mirrors are seen to change position as much as a billionth of a billionth of a meter, it could indicate the existence of fluctuations in the fabric of space. If such a spacetime jitter exists, it would present another explanation of why the universe is accelerating besides the current one involving dark energy.

US House passes NIST and DOE laboratory legislation

18 August 2014
A new speedy process for passing noncontroversial legislation has worked in favor of NIST and DOE.

Musical pitch perception starts early

18 August 2014
Tasked with extracting the fundamental frequency from a complex of high harmonics, three-month-old infants outperformed many adults.

Could an "electric Armageddon" bring civilization "to a cold, dark halt"?

15 August 2014
Observers in the media consider huge electromagnetic disruptions, both solar and human-caused.