Building on a 30-year, three-generation study of depressed individuals, their children and offspring, a study published in the journal Psychiatry Research: Neuroimaging provides a better understanding of the familial risk for depression and the role neuroplasticity might have in increasing the risk of developing depression.

The research by scientists at Children's Hospital Los Angeles and Columbia University shows a link between a particular allele for serotonin found at a higher frequency in those at risk of depression because of family history, and those who go on to develop major depressive disorder.

Caltech researchers have found evidence of a giant planet tracing a bizarre, highly elongated orbit in the outer solar system. The object, which the researchers have nicknamed Planet Nine, has a mass about 10 times that of Earth and orbits about 20 times farther from the sun on average than does Neptune (which orbits the sun at an average distance of 2.8 billion miles). In fact, it would take this new planet between 10,000 and 20,000 years to make just one full orbit around the sun.

The researchers, Konstantin Batygin and Mike Brown, discovered the planet's existence through mathematical modeling and computer simulations but have not yet observed the object directly.

COLUMBIA, Mo. - Approximately half of the companies listed with Standard & Poor have adopted policies mandating retirement based on age. A new study from the University of Missouri has found that although these mandatory retirement polices represent an effective way to address underperforming CEOs, accumulated job experience improves performance and counters age-related declines.

While research has already established that B vitamin supplements can help slow mental decline in older people with memory problems, an international team have now found that having higher levels of Omega-3 fatty acids in your body could boost the B vitamins' effect.

The team, from the Universities of Cape Town, Oslo, Oxford and the UAE, studied more than 250 people with mild cognitive impairment (MCI) in Oxford. MCI is when brain function is below what is normally expected for a person's age but is not significant enough to interfere with daily life. While it is not as serious as dementia, if untreated it often progresses to become dementia.

DURHAM, N.C. -- When the cancer-causing Epstein-Barr virus moves into a B-cell of the human immune system, it tricks the cell into rapidly making more copies of itself, each of which will carry the virus.

To satisfy a sudden increase in demand for more building parts, rapidly dividing host cells will chew up their insides to free up more amino acids, fats and nucleotides.

But if supplies of these materials run low, the cell will enter a suspended state called senescence and cell division will stop, freezing the advance of the virus, according to new findings from a Duke University research team that appear in Proceedings of the National Academy of Sciences.

Children whose GPs are easy to access are less likely to visit A&E than those whose GPs are less able to provide appointments. During weekdays, children's visits to A&E peak after school hours.

Heartbeats can now be measured without placing sensors on the body, thanks to a new way to measure heartbeats remotely, in real time, and under controlled conditions with as much accuracy as electrocardiographs.

The researchers say this will allow for the development of "casual sensing" -- taking measurements as people go about their daily activities, for instance, when they are going to bed or getting ready to start the day. Kind of like a Fitbit, except accurate

"Taking measurements with sensors on the body can be stressful and troublesome, because you have to stop what you're doing," says Hiroyuki Sakai, a researcher at Panasonic. "What we tried to make was something that would offer people a way to monitor their body in a casual and relaxed environment."

New research from the University of Southampton indicates that the public are being exposed, without their knowledge, to airborne ultrasound.

The study found increasing exposure to ultrasound in locations such as railway stations, museums, libraries, schools and sports stadiums, in which there have been complaints of nausea, dizziness, migraine, fatigue and tinnitus.

Ultrasound in public places can be generated from a number of sources including loudspeakers, door sensors and public address systems.

NAIROBI, KENYA (20 January 2016)--Small, family farmers in Africa purchase more than half of their seeds every year through local markets and other informal sources--neglected outlets that present a major opportunity for improving access to better crop varieties crucial to dealing with climate, nutrition, and other production challenges in a region where food security remains a major concern. That's a key finding from comprehensive new research released today in the Journal Food Security that examined some 10,000 seed transactions across five African countries and Haiti.

Social media may seem to be a way to make and maintain hundreds of friendships. But University of Oxford research, supported by Dorset bakers Thomas J. Fudge's, suggests that the constraints that limit the number of friends we have offline also apply online. The study is published in the journal Royal Society Open Science.

Offline, research has given rise to what's called the Social Brain Hypothesis. This says that our brain's ability to process multiple relationships creates a natural group size for humans of 100 - 200 people. This size is also constrained by the time required to maintain relationships - we only have so much time to devote to meeting or talking to people.