A quasiparticle called the exciton is responsible for the transfer of energy within devices, such as solar cells, LEDs, and semiconductor circuits, and has been understood for decades, but exciton movement within materials has never been directly observed.

Last winter's curvy jet stream pattern brought mild temperatures to western North America and harsh cold to the East and it may have seemed exceptional in the era of 24-hour news, but it's been happening that way for about 4,000 years, according to a new study. 

Since the discovery of the Antarctic ozone hole, scientists, policymakers, and the public have wondered whether we might someday see a similarly extreme depletion of ozone over the Arctic.

A new MIT study finds it isn't a big worry. In the 30 years of international efforts to limit ozone-depleting chemicals, ozone levels in the Arctic haven't yet sunk to Antarctica levels. Picking one solution and declaring it the savior may not be valid; in Canada, ozone-depleting chemicals dropped but ozone still went up, forcing policymakers to scramble and claim it must be coming from Asia.

When it comes to charitable giving, some countries open their collective wallets more than others. According to a new study in the Journal of Consumer Research, people who live in countries that promote equality in power and wealth are more likely to donate money than those who live in societies that expect and accept inequality.

"Our research examines whether cultural values can explain the different levels of charitable giving between different countries," write authors Karen Page Winterich (Pennsylvania State University) and Yinlong Zhang (University of Texas, San Antonio).

New Zealand's pastoral landscapes are some of the loveliest in the world, but they also contain a hidden threat. Many of the country's pasture soils have become enriched in cadmium. Grasses take up this toxic heavy metal, which is then eaten by the cattle and sheep that graze them. The problem is not unique to New Zealand; cadmium-enriched soils being reported worldwide.

The concern is that if cadmium concentrations rise to unsafe levels in meat and dairy products, human health and New Zealand's agricultural economy could be jeopardized. That so far hasn't happened.

WINSTON-SALEM – April 15, 2014 – Vitamin D deficiency and cognitive impairment are common in older adults, but there isn't a lot of conclusive research into whether there's a relationship between the two.

A new study from Wake Forest Baptist Medical Center published online ahead of print this month in the Journal of the American Geriatrics Society enhances the existing literature on the subject.

Food-poisoning outbreaks linked to Escherichia coli are often associated with tainted meat products but up to 30% of these are caused by people eating contaminated vegetables, and that has risen with the popularity of the organic process, as was seen in the 2011 outbreak in Europe that caused 53 deaths.

A new presentation at the Society for General Microbiology's Annual Meeting in Liverpool showed that disease-causing E. coli O157:H7 interacts directly with plant cells, allowing it to anchor to the surface of a plant, where it can multiply.

Antibiotics improve growth in children at risk of undernourishment in low and middle income countries, according to a literature review in the British Medical Journal.

Malnutrition in early childhood, reflected in poor growth, is the cause of nearly half of all mortality worldwide in children less than five years old. Antibiotics are currently recommended by the World Health Organization (WHO) for severely malnourished children, and those infected or exposed to HIV, to reduce mortality. But while antibiotics have been linked to significant height and weight gains among children from undernourished populations in countries such as Guatemala, Malawi, Zambia, and Brazil, some studies have found no significant effect of antibiotics. 

Women going through menopause most likely think of it as the time for an end to monthly periods - and it will be, but not without some false alarms. Researchers at the University of Michigan say it's normal for the majority of women to experience an increase in the amount and duration of bleeding episodes, which may occur at various times throughout the menopausal transition.

The scholars offer the first long-term study of bleeding patterns in women of multiple race/ethnicities who were going through menopause. They say the results could impact patient care and alleviate undue concern about what to expect during this life stage that can last anywhere from 2-to-10 years.

In 1993, five people died in a clinical trial of fialuridine, a nucleoside analogue to treat hepatitis B virus infection.

An analysis by the US National Academy of Sciences of all preclinical fialuridine toxicity tests, which included studies in mice, rats, dogs, and monkeys, concluded that the available animal data provided no indication that the drug would cause liver failure in humans. So it's been a 21 year search to try and find ways to make trials safer.