A Cochrane Systematic Review of the use of electronic mosquito repellents (EMRs) failed to find any evidence that they work. The researchers therefore say that there is no reason for recommending their use, and that there is no reason for even trying to do more research with the devices.

Women who have unprotected sexual intercourse or experience contraceptive failure can seek emergency contraception to reduce their chance of unintended pregnancy. Emergency contraception is a safe medication, and to be effective, must be taken within five days of unprotected intercourse. Several barriers can discourage use of emergency contraception, including an inability to obtain the medication fast enough. One proposed solution is to let women have a set of the tablets that they can keep for immediate use should it be needed.

Trials lasting 4 to 8 weeks indicate that including wholegrain oats in your diet may lower total and low-density lipoprotein cholesterol.

Coronary heart disease (CHD) is a major cause of death and ill health. One of the risk factors for CHD is elevated blood levels of total cholesterol and of low density lipoprotein cholesterol. Existing observational studies indicate that wholegrain cereals may reduce the risk of CHD, possibly by reducing cholesterol levels.

Temporal sequence represents the main principle underlying episodic memory. The storage of temporal sequence information is thought to involve hippocampus-dependent memory systems, preserving temporal structure possibly via chaining of sequence elements in heteroassociative networks.

Converging evidence indicates that sleep enhances the consolidation of recently acquired representations in the hippocampus-dependent declarative memory system. Yet, it is unknown if this consolidation process comprises strengthening of the temporal sequence structure of the representation as well, or is restricted to sequence elements independent of their temporal order.

Put a human and a chimpanzee side by side, and it seems obvious which lineage has changed the most since the two diverged from a common ancestor millions of years ago. Such apparent physical differences, along with human speech, language and brainpower, have led many people to believe that natural selection has acted in a positive manner on more genes in humans than in chimps.

But new research at the University of Michigan challenges that human-centered view.

Researchers from the Woods Hole Oceanographic Institution (WHOI) are venturing this month to the North Pole to deploy instruments that will make year-round observations of the water beneath the Arctic ice cap. Scientists will investigate how the waters in the upper layers of the Arctic Ocean—which insulate surface ice from warmer, deeper waters—are changing from season to season and year to year as global climate fluctuates.

The Arctic expedition is part of a multi-year, multi-institutional program to establish a real-time, autonomous Arctic Observing Network.

Giovanna Tinetti is an expert on detecting signs of life across interstellar space. She has worked at JPL, Caltech and the Institut d’Astrophysique de Paris, and has just won an Aurora Fellowship to pursue her research on biosignatures at University College, London. We caught up with her as she made an exploratory visit to the city that will be her home for the next three years.

How do you describe yourself?

Climate change could trigger "boom and bust" population cycles that make animal species more vulnerable to extinction, according to Christopher C. Wilmers, an assistant professor of environmental studies at the University of California, Santa Cruz.

For the past three years a satellite has circled the Earth, collecting data to determine whether two predictions of Albert Einstein's general theory of relativity are correct.

Are you ready for "X-ray glasses" that see through fog - and even clothing? With their new world record in high-frequency submillimeter waves, researchers at the UCLA Henry Samueli School of Engineering and Applied Science are bringing that kind of imaging technology closer to reality.

The record-setting 324-gigahertz frequency was accomplished using a voltage-controlled oscillator in a 90-nanometer complementary metal-oxide semiconductor (CMOS) integrated circuit, a technology used in chips such as microprocessors.