Earth

Whether a quantum object behaves like a wave or like a particle depends (according to the Copenhagen interpretation) on the choice of measurement apparatus used for observing the system, and therefore on the type of measurement performed.

SAN DIEGO – New research suggests that drinking sweetened beverages, especially diet drinks, is associated with an increased risk of depression in adults while drinking coffee was tied to a slightly lower risk. The study was released today and will be presented at the American Academy of Neurology's 65th Annual Meeting in San Diego, March 16 to 23, 2013.

With the first explosions of atomic bombs, the world became witness to one of the most important and consequential principles in physics: Energy and mass, fundamentally speaking, are the same thing and can, in fact, be converted into each other.

This was first demonstrated by Albert Einstein's Theory of Special Relativity and famously expressed in his iconic equation, E=mc2, where E stands for energy, m for mass and c for the speed of light (squared).

ROSEMONT, Ill.—Female athletes are three times more likely to suffer from anterior cruciate ligament (ACL) ruptures, one of the most common knee injuries, compared to male athletes. The ACL is one of the four main ligaments within the knee that connect the femur (upper leg bone) to the tibia (lower leg bone).

Foreign invaders such as pythons and lionfish are not the only threats to Florida's natural habitat. The native Carolina Willow is also starting to strangle portions of the St. Johns River.

Typically researchers count the number of animal species discovered in a region to determine how many different types of animals once lived there. Scientists call that a measure of faunal richness.

Myers took a different approach. Using a traditional method typically used to estimate carbon dioxide in the ancient atmosphere, Myers instead applied it to estimate the amount of CO2 in ancient soils.

Cambridge, Mass. - January 8, 2013 - At a time when communication networks are scrambling for ways to transmit more data over limited bandwidth, a type of twisted light wave is gaining new attention. Called an optical vortex or vortex beam, this complex beam resembles a corkscrew, with waves that rotate as they travel.

Now, applied physicists at the Harvard School of Engineering and Applied Sciences (SEAS) have created a new device that enables a conventional optical detector (which would normally only measure the light's intensity) to pick up on that rotation.

Alexandria, VA – The size and type of earthquakes a given fault system may produce remain poorly understood for most major fault systems. Recent superquakes, such as the March 2011 magnitude-9 off Japan and the December 2004 magnitude-9-plus off Sumatra, have been far larger than what most scientists expected those faults to produce. The problem is that current models rely on short historical records, and even shorter instrumental records.

Graphene oxide has a remarkable ability to quickly remove radioactive material from contaminated water, researchers at Rice University and Lomonosov Moscow State University have found.

A collaborative effort by the Rice lab of chemist James Tour and the Moscow lab of chemist Stepan Kalmykov determined that microscopic, atom-thick flakes of graphene oxide bind quickly to natural and human-made radionuclides and condense them into solids. The flakes are soluble in liquids and easily produced in bulk.

The American Chemical Society (ACS), the world's largest scientific society, today launched a new video series that will feature noted scientists discussing the status of knowledge in their fields, their own research, and its impacts and potential impacts on society.

Chemists at the University of California, Davis, have engineered blue-green algae to grow chemical precursors for fuels and plastics -- the first step in replacing fossil fuels as raw materials for the chemical industry.

"Most chemical feedstocks come from petroleum and natural gas, and we need other sources," said Shota Atsumi, assistant professor of chemistry at UC Davis and lead author on the study published Jan. 7 in the Proceedings of the National Academy of Sciences.

An international team of scientists has described a fossil marine predator measuring 8.6 meters in length (about 28 feet) recovered from the Nevada desert in 2010 as representing the first top predator in marine food chains feeding on prey similar to its own size. A paper with their description will appear the week of January 7, 2013 in the EE (early electronic) issue of Proceedings of the National Academy of Sciences.

Writing in PNAS, a University of Manchester physicist has discovered that some games are simply impossible to fully learn, or too complex for the human mind to understand.

Dr Tobias Galla from The University of Manchester and Professor Doyne Farmer from Oxford University and the Santa Fe Institute, ran thousands of simulations of two-player games to see how human behaviour affects their decision-making.

In simple games with a small number of moves, such as Noughts and Crosses the optimal strategy is easy to guess, and the game quickly becomes uninteresting.

PHILADELPHIA — Directed assembly is a growing field of research in nanotechnology in which scientists and engineers aim to manufacture structures on the smallest scales without having to individually manipulate each component. Rather, they set out precisely defined starting conditions and let the physics and chemistry that govern those components do the rest.

PHILADELPHIA — Though churning smokestacks, cud-chewing cows and gasoline-burning vehicles are contributing constantly to greenhouse gas emissions, there are also many processes that do the reverse, pulling molecules like carbon dioxide out of the atmosphere. One of these is chemical weathering, which occurs when rock turns into soil. Carbon dioxide molecules and rain combine to dissolve rock, and the weathering products, including sediment, eventually make their way through waterways to the ocean where some become trapped on the ocean bottom and in coral reefs and seashells.