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Research on artificial photosynthesis makes progress

10 March 2015

MIT Technology Review: The Joint Center for Artificial Photosynthesis (JCAP) was established by the Department of Energy in 2010 as one of the agency's Innovation Hubs. Now the center's researchers have demonstrated a device that uses solar energy to electrolyze water. Electrolysis produces hydrogen gas, which can be stored and used to generate electricity. With conventional electrolysis, it costs between $10 and $20 to produce the amount of hydrogen fuel equivalent to one gallon of gasoline. Solar electrolysis could reduce that cost to $2–4, according to JCAP director Nathan Lewis. The system that JCAP developed combines electrolysis catalysts with solar cells to produce a less complex system of electrodes that have a lifetime of 1000 hours. Although that is not long enough for commercial devices, it shows significant progress. However, the $122 million originally provided to JCAP will run out later this year unless Congress provides more funding.

Florida DEP employees told not to use terms “climate change” and “global warming”

10 March 2015

Miami Herald: In 2011, Governor Rick Scott took office in Florida and appointed Herschel Vinyard Jr as the director of the state’s Department of Environmental Protection (DEP). According to many DEP employees, shortly thereafter they were instructed to stop using phrases such as “climate change” and “global warming” in official documents and statements. However, both Tiffany Cowie, the DEP’s press secretary, and Jeri Bustamante, Scott’s spokeswoman, have denied that any such policy was ever put in place. Scott has previously said that he was not convinced by the evidence for climate change and also that he is “not a scientist.” Florida is under severe threat from the effects of climate change; up to 30% of its beaches are predicted to be submerged by the end of the century as sea levels rise.

Changes on the horizon for Europe’s Human Brain Project

10 March 2015
Nature: The ambitious €1 billion ($1.1 billion) Human Brain Project (HBP), which is funded by the European Union and involves hundreds of researchers, aims to better understand the human brain and its functions, create an artificial brain, and develop new supercomputing techniques. Despite having just been launched in October 2013, however, the project is already experiencing problems. On 26 February, its board of directors voted to disband its three-person executive committee after receiving complaints from more than 150 leading neuroscientists who were unhappy with the committee’s decision to cut cognitive and systems neuroscience from its initiative. A mediation committee was appointed to analyze the situation. In its final report, which has been sent to the HBP board for approval, the mediation committee not only recommends reinstating cognitive and systems neuroscience but also making changes to the HBP’s governance.

Winds on Mars may have helped shape its canyons

10 March 2015
Science: Water may not have been the dominant force that carved out the numerous canyons on the surface of Mars. From their study of 36 bedrock canyons in northeast Chile, Jonathan Perkins of the University of California, Santa Cruz, and colleagues found that those exposed to strong, sand-bearing winds grew 10 times faster than those shielded from the wind by mountains. Although Mars differs from Earth in atmosphere, gravity, and rock types, its winds could also have sandblasted and scoured its surface long after its water disappeared. If so, the group’s findings could influence estimates of how much water once flowed on Mars.

Val L. Fitch

9 March 2015

Gerry Neugebauer

9 March 2015

A rubbery material that shifts between planar and three-dimensional states

9 March 2015
The dimension change results from topology and stretchy components.

Not just for smart dead guys

9 March 2015
A high-school physics teacher and his students recreate Henry Cavendish’s famous gravity experiment.

Italy and UK vie to provide headquarters for giant telescope

9 March 2015
Nature: The Square Kilometre Array (SKA) is a large radio telescope to be built in Australia and South Africa. Although construction won’t begin until 2018, two countries are currently contending to serve as its headquarters. Until now, the Jodrell Bank Observatory near Manchester, UK, has been serving as the project’s provisional headquarters. However, Padua, Italy, has also put forth a proposal to host it, in a medieval castle, Castello Carrarese. The SKA headquarters will be responsible for allocating observation time on the telescope, making decisions on upgrades, and managing other policy areas. Both sites meet SKA’s needs, but Padua is said to support a larger community of astronomers, whereas Manchester has a stronger radio astronomy tradition. After further discussion of the two proposals, the SKA organization says it should reach a decision in a few weeks.

Why light sensors in human eye are located at the back

9 March 2015
BBC: Scientists have known for some time that the optical structure in the retina of vertebrates is built backward, with the neurons in front of the photoreceptors rather than behind them. Now Erez Ribak of the Technion–Israel Institute of Technology and colleagues propose one possible explanation. Through the use of in vitro experiments in a mouse model, computer simulations, and three-dimensional scans created with confocal microscopy, the researchers show that the neurons function like optical fibers to funnel red and green light into the eye’s cone cells while allowing blue light to spill over to the rod cells. Red and green light allow humans to see color during the daytime, and blue light allows humans to see in black-and-white under low-light conditions. Thus the eye's structure is "optimized for our vision purposes," according to Ribak. The researchers presented their findings at last week’s American Physical Society meeting in San Antonio, Texas.

NASA unveils evidence of ancient Martian ocean

9 March 2015

Guardian: A team of researchers led by Geronimo Villanueva of NASA's Goddard Space Flight Center in Greenbelt, Maryland, reports that Mars used to have an ocean that held more than 20 million km3 of water. The team used several IR telescopes to study the Martian atmosphere for six years; they looked specifically at seasonal and regional changes in water molecules. Normal water molecules in the atmosphere are able to escape Mars's gravitational pull, but heavy water molecules, in which one or both hydrogen atoms have been replaced by deuterium, are not. Consequently, the concentration of deuterium in the planet's atmosphere and in ice can be used to infer historical water levels on the planet's surface. According to the researchers' calculations, if Mars were smooth, it would have been inundated to a depth of 137 m. Given its terrain, however, the researchers suggest that the water pooled into an ocean that covered 20% of the planet's surface. As Mars lost its atmosphere, much of its water vaporized and was then lost to space. The remaining water, which is frozen in the polar ice caps, is only 13% of the volume of the ancient ocean.

Strong correlation found between climate change and California drought

9 March 2015

Ars Technica: A comparison of historical climate data from California with different climate models has shown the influence of human-driven climate change. Noah Diffenbaugh, Daniel Swain, and Danielle Touma of Stanford University examined the state's records of temperature, rainfall, and drought conditions and evaluated the severity of different periods of warming and drought using the Palmer Hydrological Drought Index and the Palmer Drought Severity Index. They then compared those periods with a range of global climate models. The models that included only naturally occurring variations did not accurately depict California's warm periods, but the models that included anthropogenic warming did. The researchers believe that anthropogenic warming has increased the simultaneous occurrence of periods of both warming and decreased rainfall, which has resulted in an increase in the frequency and severity of droughts across the state.

Nanobubbles distinguish themselves from impostors

6 March 2015
Snapshots of the way the tiny bubbles die hint at the origins of their Methuselah-like longevity.

Physicists in novels

6 March 2015
Why did Ian McEwan choose a physicist as the main character of his 2010 novel Solar?

Science has a new fact advocate for media and other public discourse

4 March 2015
SciCheck monitors, researches, and corrects faulty science statements by “major US political players” of any party.

(Basil) John Mason

4 March 2015

Brian Manley

4 March 2015

Australian research facilities face funding threat

4 March 2015

Sydney Morning Herald: A budget fight in Australia's federal government threatens the funding for a number of the nation's research institutes. According to a letter written by the National Research Alliance to Prime Minister Tony Abbott, many of the National Collaborative Research Infrastructure Strategy's 27 agencies will be forced to shut down if their funding is delayed. The facilities require just $150 million in annual operating costs, but that money supports more than $2 billion worth of infrastructure and equipment.

Galaxy formed in early universe is dustier than expected

4 March 2015

Los Angeles Times: Gravitational lensing has revealed a galaxy that, despite being just 700 million years old, has a dust-to-gas ratio similar to that of the Milky Way, which is 13 billion years old. Darach Watson of the University of Copenhagen and his colleagues were able to examine the distant galaxy because its light gets amplified by passing through a massive galaxy cluster called Abell 1689. Galaxies that formed early in the universe's history had not been expected to have collected much dust because most early dust would have been reused to form new stars.

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