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Updated: 4 days 3 hours ago

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.

Single-atom-thick sheets of silicon make for ultrafast transistors

3 February 2015

MIT Technology Review: Silicene is a single-layer molecule made from silicon. Like its carbon-based cousin graphene, silicene has unusual properties that make it potentially very useful in electronics. Unlike graphene, silicene does not occur naturally and is much less chemically and structurally stable in a two-dimensional form. Now, Deji Akinwande of the University of Texas at Austin and his colleagues have developed a method of growing the material that helps strengthen the molecule. They used the silicene as the base for contacts for a transistor, and the setup was stable in a vacuum. Although far from being commercially practical, the demonstration represents a significant proof of concept for the development of silicene-based electronics.

Marvin D. Girardeau

3 February 2015

Ibises in flight take turns to reduce drag

3 February 2015
New Scientist: Birds fly in a V formation to boost the efficiency and range of the entire flock. But how the birds decide which one will take the leading position has been unclear. Now Bernhard Voelkl of Oxford University and colleagues, who have been studying the flight patterns of northern bald ibises, say the birds pair off and take turns. The researchers tagged a flock of 14 with GPS data loggers to track the flying positions of each individual. They found that the lead bird and the one flying immediately behind it switch places frequently, taking equal turns at leading and following. Such reciprocal altruism allows the birds to help each other, and the direct reciprocation of working in pairs lessens the opportunity for cheating. The cooperation the birds exhibit in flight has not been observed when they are on the ground.

Search for primordial gravitational waves moves forward

3 February 2015

Nature: Last week it was confirmed that the apparent ripples in the cosmic microwave background (CMB) radiation detected by BICEP2 were almost entirely due to intergalactic dust. Nevertheless, researchers have been continuing to develop more sensitive experiments to look even more closely at the CMB. A set of five telescopes, each individually as sensitive as BICEP2, called the Keck Array, is undergoing upgrades that will allow it to measure both the dust and the CMB in the same patch of sky. BICEP3, the successor to BICEP2, will match the Keck Array's sensitivity in a single telescope. The biggest difference from its predecessor is that BICEP3 will be examining the sky at the lower 95 GHz frequency, where it is believed dust will cause less interference on potential signals. Both BICEP3 and the Keck Array will be looking at the same area of sky as BICEP2 did, but two other projects are already looking at wider areas of the sky and could potentially find a signal before either BICEP3 or the Keck Array is operational.

Efforts to rebuild early computer turn up original part

3 February 2015
BBC: The National Museum of Computing (TNMOC) in the UK is attempting to reconstruct one of the world’s first computers. Built in the late 1940s, the Electronic Delay Storage Automatic Calculator, or EDSAC, comprised some 3000 vacuum tubes arranged on 140 chassis that were mounted on 12 racks. The computer operated from 1949 to 1958, when it was decommissioned and dismantled. Now one of the original parts of EDSAC, the chassis 1A, has turned up in the US. Robert Little of Allentown, Pennsylvania, contacted TNMOC after hearing about the rebuild effort. Not only did he donate the part but he also provided information about what happened to the rest of the machine: When EDSAC was dismantled, an auction was held and the parts sold off. Andrew Herbert, who is leading the reconstruction project, says other parts of the original machine may still exist and could turn up as people are made aware of the rebuild effort.

New AAAS chief’s appointment stirs debate about the boundary between science and politics

3 February 2015
The American Association for the Advancement of Science’s Rush Holt inspires disagreement at Nature.

Biomechanical measurements in the fast lane

3 February 2015
A dozen microscopes in one allow high throughput characterization of biofluids.

Polarization of light used to make Möbius strips

2 February 2015

New Scientist: If you take a strip of paper and give it a half twist and tape the ends together, the result is the one-sided loop known as a Möbius strip. Now, Peter Banzer of the Max Planck Institute for the Science of Light in Erlangen, Germany, and his colleagues have demonstrated a similar effect using light. In 2005 it was predicted that light's polarization could become twisted like a Möbius strip. Banzer and his team achieved the effect by scattering two polarized beams off gold nanoparticles in such a way that the beams interfered with each other. The resulting light had polarizations with either three or five twists. The ability to twist polarized light could reveal details about light's 3D structure, which could lead to uses in biomedical imaging and particle manipulation.

Yucca Mountain proposal deemed safe but is not recommended

2 February 2015

Nature: On 29 January, the Nuclear Regulatory Commission (NRC) released the final two volumes of its technical analysis of the Department of Energy's proposal to use Yucca Mountain in Nevada as a nuclear waste repository. Although the report indicates that DOE's plan is sound, the NRC does not recommend going ahead with the construction. President Obama abandoned the project five years ago. Yet a federal court ruled that the NRC had to continue the study while it still had funds to do so. Even if Congress were to provide more funding for the next step (a further analysis of ecological impacts), the local governments in Nevada are openly resistant to selling the land to the federal government. Without that land, construction cannot begin.

Poll finds growing Republican support for action on climate change

2 February 2015
New York Times: According to a recent telephone poll, a growing number of Americans believe that climate change is occurring and is caused by human activity. In addition, a majority of Americans support government action to fight global warming, and two-thirds prefer political candidates who say they will take on that challenge. The poll was conducted by the New York Times, Stanford University, and Resources for the Future, a nonpartisan environmental research group. Although by party, Democrats are much more likely than Republicans to feel that global warming is an important issue, the poll found that 61% of Republicans admit that reducing emissions is essential to curbing global warming and 51% say the government needs to take action. Many Republican politicians, however, continue to resist efforts to curb global warming on the basis that they will hurt the economy.

Cold plasma shown to fight norovirus

2 February 2015
BBC: Human norovirus is the most common cause of acute gastroenteritis, which is characterized by severe nausea, diarrhea, and vomiting. The virus spreads particularly well in crowded areas, such as cruise ships, and has been difficult to study because it is almost impossible to grow in a laboratory. Now Birte Ahlfeld and Günter Klein of the University of Veterinary Medicine in Hannover, Germany, and their colleagues propose fighting the virus using nonthermal atmospheric pressure plasma, or cold plasma. The room-temperature, ionized gas molecules, created by applying an electric field to ambient air, were shown to be successful at inactivating the virus. Cold plasmas also are being developed for other medical applications, including the treatment of dental caries.

ESA must wait for comet probe Philae to wake up

30 January 2015
BBC: Launched more than 10 years ago, the European Space Agency’s Rosetta spacecraft reached comet 67P/Churyumov–Gerasimenko last August. On 12 November, Rosetta’s robotic lander Philae touched down on the comet’s surface after having bounced twice. Thanks to its primary battery, it was able to transmit about 60 hours’ worth of data before it exhausted its power supply. However, Philae’s exact location has not yet been determined, and it has not received enough sunlight to recharge its secondary battery. ESA controllers hope that as the comet moves closer to the Sun over the next few months, Philae will be able to reboot itself and resume its communications with Rosetta.

Credit card transactions are enough to identify card holders

30 January 2015
Nature: Metadata collected from credit card transactions has provided much useful information to researchers, businesses, and others interested in consumer spending, economic trends, and so forth. To protect the card holders’ identities, their name, address, credit card number, and other information directly linked to them are deleted. However, according to a study published in Science, even without that information, card holders can still be identified. The researchers looked at three months of credit card records for some 1 million people and were able to identify 90% of them just by knowing the date and location of four of their transactions. Although complete anonymity may be impossible in this modern age, progress is being made in creating legislation to protect consumers.

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