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Updated: 1 week 11 min ago

Molecular self-assembly may allow for advancements in microchips

23 January 2015

MIT Technology Review: As microchips become smaller, photolithography, the current technique for producing them, is reaching its limits in terms of complexity and expense. A group of researchers at IBM has demonstrated a process of molecular directed self-assembly that may provide a method for making significantly smaller microchips. By carefully preparing a set of block copolymers, and guiding the molecules' positioning using existing photolithography methods, the team was able to create circuit features that were separated by just 29 nm. Current methods are limited to separations of 80 nm. The potential increase in density of microchip circuitry could lead to much smaller chips and significant advances in processing power.

Doomsday Clock moves 2 minutes closer to midnight

23 January 2015

Science: The Doomsday Clock is maintained by the board of the Bulletin of the Atomic Scientists (BAS) as a representation of how close the world is to a global disaster. On 22 January, BAS executive director Kennette Benedict announced that the organization would be moving the clock hands 2 minutes closer to midnight, setting the symbolic time as 11:57pm. Benedict said that the reasons for the change include the recent stalling in nuclear disarmament talks and the growing threat of climate change. The time change is just the 18th since the clock's creation in 1947. It has ranged from just two minutes to midnight in 1953 to 17 minutes to midnight in 1991.

Donald Edwin Hudson

23 January 2015

Two planets may exist far beyond Pluto

23 January 2015
Ars Technica: Two new planets may have been discovered—in our solar system. Their presence has been detected through their apparent gravitational influence on a group of space rocks known as extreme trans-Neptunian objects, which orbit the Sun far beyond Neptune. One of the two possible planets, 2012 VP113, was first detected last year and appears to be about 250 astronomical units away; the second orbits at about 200 AU. If the two do indeed exist and turn out to be much more massive than Earth, their existence would contradict current models of the solar system. Further study will be required before the two objects’ status as planets can be confirmed.

Norman Rostoker

23 January 2015

Hans Kahlmann

23 January 2015

To maintain swarm, jellyfish can swim against current

23 January 2015
BBC: Jellyfish tend to congregate in large swarms called blooms, comprising hundreds to millions of organisms. Until recently no one knew exactly how they were able to form and maintain those blooms. Now researchers show that jellyfish can sense ocean currents, actively orient themselves, and swim against the current when necessary. Graeme Hays of Deakin University in Australia and colleagues tagged jellyfish with data loggers to measure their acceleration and orientation; the researchers also used floating sensors to monitor ocean currents. Because jellyfish blooms are proliferating and can disrupt human activities such as swimming and fishing, the researchers hope their findings will allow better predictions of bloom magnitude and movements. However, how the jellyfish know what direction to travel is still unknown.

Lawrence Ernest Williams

23 January 2015

How to obtain and write references

23 January 2015
What to do when Voldemort writes you a letter of recommendation (and other scenarios).

Vernon E. Leininger

23 January 2015

Trivial implausibility

23 January 2015
Despite a manifestly unscientific plot element, the comic series The Wake is a compelling read and a visual feast.

Astrophysicist Adam Frank frames Earth's sustainability transgalactically

23 January 2015
The science popularizer says exoplanets across the Milky Way likely tell a lot about human-caused climate disruption’s ultimate effects.

Laser etching renders metals extremely water-repellent

22 January 2015
BBC: Metal surfaces etched by femtosecond laser pulses are more slippery than Teflon and have been shown to be very effective at repelling water. They are so hydrophobic that water drops actually bounce off them, says Chunlei Guo of the University of Rochester in New York, one of the authors of a paper published in the Journal of Applied Physics. Because the water droplets also remove dust particles from the surface, the materials are self-cleaning. Guo and his research team think the technique would be useful in developing countries to create hygienic surfaces for medical or sanitary uses.

Israel's arrest of Palestinian physicist spurs international protest

22 January 2015

Nature: Imad Ahmad Barghouthi, a theorist who studies space-plasma physics at Al-Quds University in Jerusalem, was detained without charges on 6 December 2014 as he crossed the border from the West Bank into Jordan. In response to Barghouthi's detainment, several international science organizations have sent letters of protest to the Israeli government and to European organizations that provide research funds to Israel. Barghouthi was on his way to Amman to catch a flight to the United Arab Emirates so that he could attend a meeting of the Arab Union of Astronomy and Space Sciences in Sharjah. Since his arrest, he has been held in an Israeli military prison without being charged under a policy that allows Israel to hold a potential security risk for three months. Jawad Boulos, Barghouthi's lawyer, believes that Barghouthi was detained because of statements he made in support of Palestinian activists during Israel's 2014 invasion of the Gaza Strip. Barghouthi is now scheduled to be released on 2 February, but could be held longer.

Senate amends Keystone XL bill to say that climate change is real

22 January 2015

Science: The US Senate voted 98 to 1 to approve an amendment to the Keystone XL Pipeline bill that says climate change is real and not a hoax . Proposed by Sheldon Whitehouse (D-RI), the amendment was one of several put forward by opponents of the pipeline, which would bring oil from Canada to the US. However, it was the only one to be approved. Other amendments that further stated that climate change was directly influenced by human activity and pollution had also been proposed. The Keystone XL bill is heavily supported by Republicans, many of whom have dodged the issue of climate change by saying they aren't scientists. Some, such as James Inhofe (R-OK), had called climate change a "hoax" in the past. Before the vote, Inhofe clarified that statement by saying the hoax is that people think that humanity can change the climate.

How did dwarf galaxies form?

22 January 2015
Confounding expectations, dwarf galaxies that lie on the plane of their galactic host resemble ones that lie in the host's halo.

Strong emotion aids memory

22 January 2015
New York Times: In humans, seemingly trivial memories, when associated with a strong emotional response, can be filed away and recalled much later. To study that phenomenon, Joseph Dunsmoor of New York University and coworkers conducted an experiment in which they showed participants a random series of photographs and asked them to categorize each image as either a tool or an animal. They were then shown another series of photos to categorize, but in this second round, half the participants received a mild shock when they saw tools, and half received the shock when they saw animals. In a series of tests to measure how well the participants remembered the photos, the results varied depending on when the test was given. Those who took it immediately remembered as many animal photos as they did tool photos. But those who took the test hours later remembered more items in the category for which they had received a shock.

Science-related excerpts from President Obama's State of the Union address

21 January 2015
It includes strong words on combating human-caused climate disruption.

Senators hope to amend Keystone XL bill with statement on climate change

21 January 2015
Science: The first bill under discussion by the Senate in the 114th Congress concerns the construction of the Keystone XL pipeline, which would bring oil from Canada to the US. The controversial bill is supported by the new Republican majority. Those senators who oppose it say the pipeline will exacerbate global warming and are pushing for amendments affirming that climate change is happening, that human activity is driving it, and that Congress should take action to address the issue. The goal of the amendments, says Charles Schumer (D-NY), is to put climate-change-denying senators in an awkward position. If they block the amendments, they could be accused of dodging the issue. If they let the amendments go to a vote, they will be forced to take an actual position on climate change, which could damage their standing with their constituencies.

Micromotors deliver therapeutic materials to mouse’s stomach

21 January 2015
BBC: For the first time, powerful microscale motors have been tested in a living organism. Researchers at the University of California, San Diego, report in the journal ACS Nano that they successfully inserted artificial micromotors, consisting of zinc-coated polymer tubes just 20 μm long, into the stomach of a mouse. The zinc reacted with the stomach acid and produced hydrogen bubbles that propelled the tiny machines into the stomach lining. As the machines dissolved, they released their cargo. The researchers believe that such artificial micromotors, which convert energy into movement, could deliver drugs much more effectively than conventional medicines, which rely on passive diffusion. The method could one day be used to treat peptic ulcers and other illnesses.

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