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Updated: 7 hours 50 min ago

Transistors may stop shrinking in five years

26 July 2016

IEEE Spectrum: Moore's law describes a historical trend concerning the density of transistors on computer chips, which has been doubling roughly every two years since the 1970s. The primary driver has been the continuing reduction in transistor size. However, a new analysis of transistor technologies suggests that by 2021 manufacturers will no longer find it economically viable to decrease the dimensions of transistors any further. The analysis, included in the 2015 International Technology Roadmap for Semiconductors, suggests that manufacturers will probably continue to be able to increase transistor density by layering transistors vertically.

Analysis shows droughts shut down Amazon carbon sink

26 July 2016

BBC: The Amazon basin is one of the world's largest carbon reservoirs, with the plants there holding roughly 17% of Earth's vegetation-stored carbon. A new study has revealed, however, that two recent droughts have adversely affected the basin's ability to absorb carbon. According to coauthor Ted Feldpausch of the University of Exeter, UK, during one of the droughts, in 2010, the rate of vegetation mortality increased and the growth rate slowed, which resulted in the region releasing more carbon than it was taking in. In nondrought years, the region absorbs hundreds of millions more tons of carbon than it loses.

Last universal common ancestor of all living things may have sprung from deep-sea vents

26 July 2016
New York Times: Three principal domains of life have been identified on Earth: bacteria, archaea, and eukaryotes. Of those, bacteria and archaea are thought to have originated first. By looking at the protein-coding genes of bacteria and archaea, William Martin of Heinrich Heine University in Germany and his colleagues now say they have identified the ancient organism from which both are descended. Called Luca, the last universal common ancestor may have lived about 4 billion years ago and appears to have developed in the intensely hot deep-sea vents where magma erupts through the ocean floor. Martin’s further claim that Luca may have been very close to the origin of life itself, however, has provoked controversy because of the organism's apparent ability to synthesize proteins, generally considered to be a fairly complex task.

<em>Solar Impulse</em> completes first solar-powered round-the-world flight

26 July 2016
BBC: After traveling for more than a year and making some 17 stops along the way, Solar Impulse 2 has successfully completed the first-ever circumnavigation of Earth by a solar-powered aircraft. The plane touched down earlier today in Abu Dhabi, United Arab Emirates, where it had begun its historic journey on 9 March 2015. The project was the brainchild of André Borschberg and Bertrand Piccard of Switzerland, who took turns piloting the craft on its 42 000 km journey across four continents, three seas, and two oceans. Over the course of the trip, the two set 19 official aviation records, including longest uninterrupted solo flight when Borschberg flew 8924 km from Nagoya, Japan, to Kalaeloa, Hawaii.

The formation of the Martian moons

25 July 2016
A new simulation strengthens the case that Mars’s two satellites condensed out of a long-gone debris disk that surrounded the planet.

China ramps up space missions

22 July 2016

Science: China's space program has set an ambitious schedule as it tries to be seen as an equal partner to NASA and the European Space Agency (ESA). The schedule includes launching more than four missions over the next 13 months. Moreover, the country's lunar exploration program hopes to launch a sample return mission next year, and its first-ever landing on the far side of the moon is planned for 2018.  Beginning in 2020 China will launch four science missions and the nation's first Mars probe. Unlike NASA or ESA, the Chinese space program doesn't receive annual funding but instead gets one lump sum every five years. That arrangement doesn't adjust for inflation or allow for last-minute plan changes. In addition, the country's different space agencies are competing for scarce resources and missions. The solution, say Chinese space administrators is to merge agencies into one.

Most comprehensive map of human brain reveals 97 new regions

21 July 2016
New York Times: After more than a century of study, the most detailed map of the human brain to date has been created, revealing almost 100 previously unknown regions. To create the map, Matthew Glasser of the Washington University School of Medicine and colleagues spent the past three years analyzing data collected by the Human Connectome Project. They combined high-resolution images of multiple aspects of the brain, including structure, function, and connectivity, which were captured as the subjects participated in various activities or simply rested. With the use of artificial-intelligence software, the researchers were able to identify not only 83 known regions in the brain but another 97 that were previously unknown or forgotten. The new, state-of-the-art map is expected to help not only brain surgeons in the operating room but also researchers to better understand brain development, aging, and brain-related disorders, such as Alzheimer’s.

Dark matter remains to be seen

21 July 2016 Despite its recent 20-month run, the Large Underground Xenon (LUX) experiment has yet to detect a dark-matter signal. LUX is just one of several experiments currently seeking signs of the weakly interacting massive particles (WIMPs) that make up some 85% of the mass of the universe. Located at the Sanford Underground Laboratory in South Dakota, LUX features a large tank of liquid xenon, whose high density makes it more likely to interact with WIMPs. Although LUX has so far failed to detect the elusive particles, the data it gathered can still be used to improve the design of future, more sensitive experiments. LUX itself is soon to be replaced with the LUX-Zeplin detector, which will be 70 times as sensitive.

Underwater microscope brings marine life into focus

21 July 2016
Some of the ocean’s smallest organisms can now be observed in their natural habitat.

High-energy lab has high-energy director

21 July 2016
CERN director general Fabiola Gianotti looks at what lies ahead for particle physics.

Facebook developing high-speed laser-based Wi-Fi

20 July 2016
PC World: Although wireless networks provide internet connectivity without the need to run physical cables, the systems can be slow, and they rely on available radio spectra. To overcome those problems, researchers at Facebook have been working on a system that uses lasers to transmit data. Because laser beams dissipate as they travel, however, a very large detector is required to collect the signal. Facebook has developed a cheap, large detector through the use of plastic optical fibers doped with organic dye molecules. Its 126 cm2 detector is thousands of times larger than earlier designs. Facebook’s prototype device has achieved 2.1 Gbps, and the company hopes to speed it up even more by switching to UV light. Such a system could be used to transmit high-definition video to mobile devices and provide low-cost communications in remote areas.

The physics of the bicycle

20 July 2016
Nature: Although bicycle design has remained relatively unchanged since the early 20th century, cycling’s recent resurgence in popularity has prompted several innovations in materials and technology. One example is the inflatable frame developed by the Ford Motor Co so the bike can be easily transported in a car or bus. Another is the redesign of a recumbent bike—the rider lies chest down—to improve its aerodynamics. Also being considered is rear-wheel steering, which would improve efficiency by allowing the chain to be shorter. To better understand the physics involved in bike design, Nature’s Brendan Borrell looks at a brief history of bicycles and the physical and mathematical forces that keep them upright and propel them forward. Borrell also mentions the “father of modern bicycle theory,” David Jones, whose article exploring bicycle stability appeared in the April 1970 issue of Physics Today.

Joint US–Russian space base near the Moon proposed to replace ISS

20 July 2016
Popular Mechanics: With the International Space Station slated to cease operations in 2024, engineers in the US and Russia have been discussing a cooperative venture to build a new space base near the Moon. Not only would the base allow for deeper exploration of Earth’s nearest satellite, it could also serve as a jumping-off point for venturing further into space. And such a project would be mutually beneficial: Russia has proven its proficiency in building space modules to house astronauts, and the US could provide the transportation as it is already developing the Space Launch System to replace the space shuttle. The project was one of many topics discussed at the recent ISS R&D Conference held in San Diego, California.

The <em>New York Times</em> and other media question clean coal’s prospects

20 July 2016
After detailing a major project’s failings, the Times launched a debate on its opinion pages with this headline: “Clean coal, or a dirty shame?”

Storing data in atoms

19 July 2016
Nature: Chlorine atoms have been used to create a tiny 1-kilobyte rewritable storage device. Sander Otte of Delft University of Technology in the Netherlands and his colleagues arranged the chlorine atoms into square grids on a copper surface. By including vacant spaces in between the Cl atoms, the researchers show how the atoms can be moved around using a scanning tunneling microscope and a sharp needle. The resulting patterns of atoms and vacancies can then be used to encode information in binary form. Such a system, if scaled up, could store hundreds of terabytes of data in a device the size of a grain of salt. Besides data storage, the technology could have other applications, such as the design of new materials.

Rebooted <em>Kepler</em> spacecraft finds more than 100 exoplanets

19 July 2016
Christian Science Monitor: Despite the failure of two of its reaction wheels in 2013, the Kepler spacecraft has managed to continue its hunt for exoplanets as part of a new, modified mission, called K2. Using Kepler’s remaining capability, researchers have already discovered 197 new planet candidates, of which 104 have been validated, 30 have been determined to be false positives, and the other 63 require further research. Four of the newly validated exoplanets could be similar to Earth. Based on the spacecraft's success so far, the researchers predict that over the course of K2's planned four-year mission, some 500 to 1000 new exoplanets may be discovered.

Brexit prompts UK science academies to urge government to prioritize research

19 July 2016
BBC: The 23 June vote by the UK to leave the European Union (EU) has prompted the presidents of seven science academies to ask the UK government to ensure that the country retains its position as a world leader in science and technology. In a joint statement, they say that “the UK’s outstanding research and innovation base is central to our economic, social and cultural well-being.” They focus on several priorities in four areas: people, collaboration, resources, and regulation. Among their requests are that researchers continue to be allowed to travel freely between the UK and EU countries, that international research collaborations continue to be encouraged and supported, that research funding issues be addressed to avoid any potential shortages during and after the transition, and that the UK remain compliant with EU rules and regulations.

Young B. Kim

19 July 2016

Tropical cyclones in a warming environment

19 July 2016
Scientists are still hammering out the potential effects of climate change on the frequency and intensity of strong storms in the tropics.

Fighting cancer by starving it

18 July 2016
Economist: Because cancer cells need nutrients to grow, Valter Longo of the University of Southern California in Los Angeles and colleagues have been trying to see whether they can fight cancer by starving it. Working with mice injected with breast-cancer cells, the researchers developed a special diet that is low in calories, proteins, and sugars. To avoid starving the animals completely and to encourage the action of tumor-infiltrating lymphocytes, the researchers added vitamin D, zinc, and fatty acids. They found that tumor growth was greatly reduced in the group of mice that were periodically forced to fast on the special diet, compared with those that were consistently fed standard rodent chow. In addition, tumor development was reduced even further among the fasting mice when a dose of the anticancer drug doxorubicin was added.