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Updated: 16 hours 40 min ago

Star birth appears to drive galactic gas cloud formation

15 December 2014

Ars Technica: The visible matter that makes up galaxies is primarily in the form of stars, but many galaxies have large clouds of molecular gas around them. How that gas got there is unclear because most theories about galaxy formation predict that the gas should have stayed in the galaxies and coalesced into stars. Now observations of a distant galaxy may provide some clues into the process. The observed galaxy, J0905, is extremely compact, with half of its star formation coming from a region just 100 parsecs in diameter. It is spewing gas outwards into space at a flow rate of 2 500 km/s, 10 times more than the average for other galaxies. Curiously, the mass of the gas lost each year is roughly equal to the mass of new stars that J0905 produces each year. Because of the galaxy's compactness, the combined radiation from the new stars appears to be the source of the "wind" driving the gas out of the galaxy.

Cytoskeleton rheology

15 December 2014
Mechanical properties of single cells can be difficult and time-consuming to unravel. A new instrument allows such properties to be deduced from experiments on a large group.

Physicist’s <em>Wall Street Journal</em> op-ed engages movies

15 December 2014
“Perils of romanticizing physics: Bravo for Interstellar and The Theory of Everything, but let’s not get carried away.”

Cutting carbon emissions could have more immediate benefits, says study

12 December 2014
Ars Technica: Previous studies have proposed that because of the heat capacity of Earth's oceans, the benefits of cutting fossil fuel emissions could take almost a half century to be realized. However, new research shows that the median time between a given carbon dioxide emission and maximum warming may be much less than that. The researchers gauged Earth’s temperature response by simulating the effect of a pulse of 100 gigatons of CO2 that abruptly ceases. The researchers focused on three variables: climate sensitivity, the ocean’s thermal inertia, and carbon cycle activity. For 90% of their simulations, surface temperature stopped rising in as little as 10 years. The point of the study was to demonstrate the early benefits of cutting greenhouse gas emissions.

The science of whiskey-residue art

26 November 2014

New York Times: Ernie Button, a photographer in Phoenix, Arizona, saw the fine lines in the filmy residue of a glass of Scotch and turned it into art by shining colored lights through the films and taking pictures. Over time, he began detecting patterns and similarities between different types of whiskeys and other alcohols. So he reached out to Peter J. Yunker, who had published a paper explaining the uneven formation of coffee rings, but Yunker was unable to help him. Button then found Howard Stone of Princeton University by doing a Google search of "fluid mechanics" and "art." Stone and his colleagues began testing different liquors and their own alcohol mixes. They found that the patterns formed because of the different evaporation rates of ethyl alcohol and water. As the alcohol evaporates, the surface tension of the water left behind changes, which in turn affects the way the water flows and the particulate residue gets distributed. They also believe that whiskey contains a surfactant and polymers that their artificial water and alcohol mixes did not. The surfactant changes the surface tension of the water, and the polymers adhere to the glass, all of which affects the resulting patterns. Stone thinks that the work has practical applications, such as improved printer inks.

Makers of neuroprostheses navigate regulatory process

26 November 2014

Nature: Rapid advances are being made in the field of brain–computer interface devices that connect with the central nervous system to restore motor control in patients with paralysis or amputation. Devices range from implants in the brain to electrodes and sensors placed on the scalp. The implants are the riskiest because they require surgery and it’s not known how long the electrodes can safely remain in the brain. As such devices will soon reach the point of being commercially viable, manufacturers are also working to ensure that they meet the safety regulations of the US Food and Drug Administration and to persuade health insurers to pay for them. The FDA recently held a workshop in Silver Spring, Maryland, to discuss and obtain public feedback on just such issues.

Quasars' orientations may be determined by universe's structure

26 November 2014

Ars Technica: Quasars, which are black holes at the center of galaxies, produce more light from their accretion disks than is produced by the rest of the stars in their parent galaxies combined. A survey of 93 extremely distant quasars by Damien Hutsemékers of the University of Liège in Belgium and his colleagues has revealed a possible connection between quasars and the universe's large-scale structure. The light from the quasars they looked at was produced when the universe was only one-third as old as it is now. The researchers noticed that some of the quasars' axes of rotation appeared to be aligned with each other despite being separated by billions of light-years. To determine just how closely aligned they were, Hutsemékers's team measured the polarization of the light from the quasars, which has previously been shown to correlate to the orientation of a quasar's accretion disk. Of the 93 quasars, 19 were highly polarized and had broad radiation spectra, a sign that the quasar is highly inclined with respect to Earth. By comparing those quasars with a map of the filamentary structure of the universe, the researchers show that the quasars are all aligned parallel to the filaments in which they are located. The researchers believe there is a less than 1% chance that this is a random distribution. 

Link found between brain development and dementia vulnerability

26 November 2014

BBC: A recent study published in the Proceedings of the National Academy of Sciences confirms the hypothesis that the parts of the brain that develop last tend to be the first to show signs of age-related decline. Moreover, two common forms of dementia, Alzheimer’s disease and schizophrenia, appear to affect the same regions of the brain. The findings highlight the possible lifelong consequences of genetic and environmental factors that occur early in life. The information is encouraging, according to medical researchers, because a better understanding of the diseases' pathology could one day allow doctors to identify those most at risk and provide a means of treating them or possibly even preventing the diseases from ever developing.

Reason the need!

26 November 2014
Spinoffs from applied research can result in unexpected and highly profitable sidelines.

From physics research to human rights advocacy

26 November 2014
Hadi Ghaemi is the cofounder and executive director of the International Campaign for Human Rights in Iran.

Turkey proposes building green city fueled by pistachio shells

25 November 2014

NPR: As the world’s third largest producer of pistachios, Turkey has had to find ways to get rid of thousands of tons of leftover shells. Now the country proposes using its green waste to its advantage by turning the shells into biogas to power a new eco-city. Other green cities have been springing up around the world, each fueled by various renewable materials, including macadamia nuts in Australia and decaying garbage in Mexico. If the project is deemed feasible, construction on the new city would begin in the next two years.

New insights on ancient astronomical computing machine

25 November 2014

New York Times: Raised from a shipwreck in 1901, the Antikythera mechanism has long puzzled scientists regarding its origins and maker. The clocklike device, with its numerous bronze gears and dials, appears to have been used to predict astronomical positions and eclipses. Hence it has sometimes been called the world’s first analog computer. Now Christián Carman of the National University of Quilmes in Argentina and James Evans of the University of Puget Sound in Washington have used the device’s eclipse predictor to more accurately date when the device was built. Based on the new information, they say the device was probably constructed around 205 BC, some 50–100 years earlier than previously believed. Although scientists have speculated that the Antikythera mechanism may be linked to the famed ancient Greek mathematician Archimedes, Evans said too little is known about ancient Greek astronomy to ascertain who could have come up with such a device.

Deadline extended for nuclear deal with Iran

25 November 2014

New York Times: Despite yesterday’s deadline, no final agreement has been reached concerning Iran’s nuclear program. Leaders from the P5 + 1 nations (China, France, Russia, the UK, and the US, plus Germany) met with Iranian officials in Vienna to try to resolve the yearlong effort to get Iran to dismantle parts of its nuclear infrastructure and cut the number of centrifuges. Although the meeting ended with no breakthrough compromise, the US and its allies have decided to extend the deadline by seven months. US secretary of state John Kerry and Iranian foreign minister Mohammad Javad Zarif, who have met several times and developed a strong working relationship, both expressed optimism that the talks had made “real and substantial progress” and that a solution may well be found in the next few months.

NASA to use twin astronauts to study effects of long-duration spaceflight

25 November 2014

Smithsonian: Mark Kelly and Scott Kelly, who have both worked as astronauts with NASA, are the only set of twins to have traveled in space. Although Mark retired three years ago, he is about to become part of a NASA study when identical twin Scott returns to space in 2015 to spend a year on board the International Space Station. No US astronaut has spent that long in space, so NASA will use the opportunity to study how the long-duration spaceflight affects Scott. The agency will look at such things as the effects of weightlessness, radiation, isolation, and confinement. Scott's results will be compared with those from tests conducted on Mark, who will remain on Earth. The results will be used to help prepare astronauts for longer space trips such as to Mars.

Brewing scientific knowledge at Carlsberg

25 November 2014
The Danish brewery’s researchers continue to improve the way beer is made, stored, and served.

So far… so far: My first four months with an electric car

25 November 2014
A fully electric car is environmentally friendly and cheap to run, but what is it like to drive?

Journalists examine the “solution aversion” response to climate science

24 November 2014
To what extent does hostility toward climate-policy proposals corrupt public climate-science understanding?

Global warming threatens US Southwest

24 November 2014

New York Times: As the average global temperature rises, mountainous areas across western North America are experiencing significantly less ice and snow. A hundred years ago, Glacier National Park included some 150 ice sheets, but today it has only 25. The implications are vast for the surrounding areas. Rising air and water temperatures are affecting local ecosystems, fish, and wildlife. And because at least 80% of the water supply in the US West comes from its mountains, the loss of the natural reservoir that glaciers provide is also being felt by cities, farms, and industry all across the region. Although manmade global warming has a significant impact on the ice retreat, it is not the only cause. And the shrinking glaciers are only the first symptom of larger changes to come, says Daniel Fagre at the US Geological Survey.

Obama's new immigration policy includes STEM provisions

24 November 2014

Science: In his speech last week, President Obama proposed several new immigration policies, some of which would directly affect the US research community, particularly those in science, technology, engineering, and mathematics (STEM) fields. Among them is a proposal to allow more foreign STEM students at US universities to work full-time and make it easier for foreign STEM researchers to seek green cards and begin work on projects that already have substantial US investor financing. Also, multinational companies would have more latitude in moving skilled workers from foreign facilities to US operations and shifting those already in the US to “same or similar” jobs. Although high-tech industries had hoped for more, some labor unions, scholars, and professional groups point out that the new policies could threaten job possibilities and wages for native-born scientists and engineers.

Exoplanet becomes center of epic astronomical controversy

24 November 2014

Wired: In astronomy, as in so many endeavors, there is a race to be first. Case in point: Gliese 667Cc, an extrasolar planet, or exoplanet, orbiting the star Gliese 667C. Although fairly universally recognized as one of the first, if not the first, Earth-like exoplanets to be discovered, Gliese 667Cc is at the center of a scientific controversy over who discovered it. A European team, using the High Accuracy Radial Velocity Planet Searcher (HARPS), published the first paper in November 2011. However, researcher Guillem Anglada-Escudé, who used archived HARPS data, claims he saw it first in August 2011 but was scooped after applying to HARPS to use its spectrograph to verify his findings. Anglada-Escudé also had been working with a group of American researchers who were trying to be the first to discover such an exoplanet. In this article for Wired, author Lee Billings, who wrote Five Billion Years of Solitude (Current, 2013), which covers the topic of the hunt for exoplanets in greater detail, provides an informative discussion of the complex thread of events leading up to the discovery of possibly the first Earth-like planet in outer space.