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September 13, 2013

Get touchy feely with plants: Gently rubbing them with your fingers can make them less susceptible to disease

Forget talking to plants to help them grow, gently rubbing them with your fingers can make them less susceptible to disease, a paper in the open access journal BMC Plant Biology reveals.

Gently rubbing the leaves of thale cress plants (Arabidsopsis thaliana) between thumb and forefinger activates an innate defense mechanism, Floriane L'Haridon and colleagues report. Within minutes, biochemical changes occur, causing the plant to become more resistant to Botrytis cinerea, the fungus that causes grey mould.

Rubbing the leaves is a form of mechanical stress. Plants frequently have to deal with mechanical stress, be it caused by rain, wind, animals or even other plants. Trees growing on windy shorelines, for example, sometimes respond by developing shorter, thicker trunks.

But plants also respond to more delicate forms of mechanical stress, such as touch. Some responses are obvious -- the snapping shut of a Venus fly trap, the folding leaflets of a touched touch-me-not plant (Mimosa pudica) -- whilst some are more discrete. Plants also launch an arsenal of 'invisible' responses to mechanical stress, including changes at the molecular and biochemical level.

Youth more likely to be bullied at schools with anti-bullying programs

Anti-bullying initiatives have become standard at schools across the country, but a new UT Arlington study finds that students attending those schools may be more likely to be a victim of bullying than children at schools without such programs.

The findings run counter to the common perception that bullying prevention programs can help protect kids from repeated harassment or physical and emotional attacks.

"One possible reason for this is that the students who are victimizing their peers have learned the language from these anti-bullying campaigns and programs," said Seokjin Jeong, an assistant professor of criminology and criminal justice at UT Arlington and lead author of the study, which was published in the Journal of Criminology.

"The schools with interventions say, 'You shouldn't do this,' or 'you shouldn't do that.' But through the programs, the students become highly exposed to what a bully is and they know what to do or say when questioned by parents or teachers," Jeong said.

September 12, 2013

Everyday sadists take pleasure in others' pain

Most of the time, we try to avoid inflicting pain on others -- when we do hurt someone, we typically experience guilt, remorse, or other feelings of distress. But for some, cruelty can be pleasurable, even exciting. New research suggests that this kind of everyday sadism is real and more common than we might think.

Two studies led by psychological scientist Erin Buckels of the University of British Columbia revealed that people who score high on a measure of sadism seem to derive pleasure from behaviors that hurt others, and are even willing to expend extra effort to make someone else suffer.

The new findings are published in Psychological Science, a journal of the Association for Psychological Science.

"Some find it hard to reconcile sadism with the concept of 'normal' psychological functioning, but our findings show that sadistic tendencies among otherwise well-adjusted people must be acknowledged," says Buckels. "These people aren't necessarily serial killers or sexual deviants but they gain some emotional benefit in causing or simply observing others' suffering."

August 20, 2013

LSD and other psychedelics not linked with mental health problems, analysis suggests

The use of LSD, magic mushrooms, or peyote does not increase a person's risk of developing mental health problems, according to an analysis of information from more than 130,000 randomly chosen people, including 22,000 people who had used psychedelics at least once.

Researcher Teri Krebs and clinical psychologist Pål-Ørjan Johansen, from the Norwegian University of Science and Technology's (NTNU) Department of Neuroscience, used data from a US national health survey to see what association there was, if any, between psychedelic drug use and mental health problems.

The authors found no link between the use of psychedelic drugs and a range of mental health problems. Instead they found some significant associations between the use of psychedelic drugs and fewer mental health problems.

July 31, 2013

Be happy - your genes will thank you for it: Doing good leads to strong immune cells

American scientists have found different types of happiness have surprisingly contrary effects on our genes.

UCLA research found that people who derive their happiness from helping others have strong antibody genes, while people who get their kicks from self-gratification can suffer from low antiviral and anitbody gene expression.

The study, which also involved the University of North Carolina, is the first of its kind to examine how positive psychology impacts human gene expression.

People who are do-gooders have high levels of 'eudaimonic well-being'.

July 24, 2013

Athletes need to be careful to monitor diet, weight to maintain muscle mass

Athletes seeking a healthy performance weight should eat high fiber, low-fat food balanced with their training regimen in order to maintain muscle while still burning fat, according to a report by an Oregon State University researcher.

The United States now has a record number of overweight athletes, a population many think of as untouched by the obesity crisis. Nationally, more than 45 percent of high school linebackers are obese, and the number of overweight students entering college level-sports is increasing.

US physicians put patients' best interests above concerns about health care costs

A new study of attitudes about health care costs reveals that an overwhelming majority of U.S. physicians feel a responsibility to address costs, but prioritize their obligations to patients' best interests over cost concerns. Results of the random survey of 2,500 U.S. physicians are published in this week's Journal of the American Medical Association (JAMA).

"Physicians feel stuck in a difficult position," says lead author Jon Tilburt, M.D., Mayo Clinic's Biomedical Ethics Program and Center for the Science of Health Care Delivery. "Despite their sense of responsibility to address health care costs, physicians consistently express a commitment to the best interests of patients even when it is expensive. Given this finding, we recommend that cost-containment strategies aimed at physician behavior should focus on innovations that not only promote savings but also preserve physicians' commitment to individual patients."

July 23, 2013

'Love hormone' is two-faced: Oxytocin strengthens bad memories and can increase fear and anxiety

It turns out the love hormone oxytocin is two-faced. Oxytocin has long been known as the warm, fuzzy hormone that promotes feelings of love, social bonding and well-being. It's even being tested as an anti-anxiety drug. But new Northwestern Medicine® research shows oxytocin also can cause emotional pain, an entirely new, darker identity for the hormone.

Oxytocin appears to be the reason stressful social situations, perhaps being bullied at school or tormented by a boss, reverberate long past the event and can trigger fear and anxiety in the future.

That's because the hormone actually strengthens social memory in one specific region of the brain, Northwestern scientists discovered.

If a social experience is negative or stressful, the hormone activates a part of the brain that intensifies the memory. Oxytocin also increases the susceptibility to feeling fearful and anxious during stressful events going forward.

Microchips that mimic the brain: Novel microchips imitate the brain's information processing in real time

Novel microchips imitate the brain's information processing in real time. Neuroinformatics researchers from the University of Zurich and ETH Zurich together with colleagues from the EU and US demonstrate how complex cognitive abilities can be incorporated into electronic systems made with so-called neuromorphic chips: They show how to assemble and configure these electronic systems to function in a way similar to an actual brain.

No computer works as efficiently as the human brain -- so much so that building an artificial brain is the goal of many scientists. Neuroinformatics researchers from the University of Zurich and ETH Zurich have now made a breakthrough in this direction by understanding how to configure so-called neuromorphic chips to imitate the brain's information processing abilities in real-time. They demonstrated this by building an artificial sensory processing system that exhibits cognitive abilities.

Most approaches in neuroinformatics are limited to the development of neural network models on conventional computers or aim to simulate complex nerve networks on supercomputers. Few pursue the Zurich researchers' approach to develop electronic circuits that are comparable to a real brain in terms of size, speed, and energy consumption. "Our goal is to emulate the properties of biological neurons and synapses directly on microchips," explains Giacomo Indiveri, a professor at the Institute of Neuroinformatics (INI), of the University of Zurich and ETH Zurich.

Skipping breakfast may increase coronary heart disease risk

A large 16-year study finds men who reported that they skipped breakfast had higher risk of heart attack or death from coronary heart disease. The timing of meals, whether it's missing a meal in the morning or eating a meal very late at night, may cause adverse metabolic effects that lead to coronary heart disease. Even after accounting for modest differences in diet, physical activity, smoking and other lifestyle factors, the association between skipping breakfast (or eating very late at night) and coronary heart disease persisted.

Here's more evidence why breakfast may be the most important meal of the day: Men who reported that they regularly skipped breakfast had a higher risk of a heart attack or fatal coronary heart disease in a study reported in the American Heart Association journal Circulation.

Researchers analyzed food frequency questionnaire data and tracked health outcomes for 16 years (1992-2008) on 26,902 male health professionals ages 45-82. They found:

-Men who reported they skipped breakfast had a 27 percent higher risk of heart attack or death from coronary heart disease than those who reported they didn't.

-The men who reported not eating breakfast were younger than those who did, and were more likely to be smokers, employed full time, unmarried, less physically active and drank more alcohol.

-Men who reported eating late at night (eating after going to bed) had a 55 percent higher coronary heart disease risk than those who didn't. But researchers were less convinced this was a major public health concern because few men in the study reported this behavior.

-During the study, 1,572 of the men had first-time cardiac events.

July 19, 2013

Facebook for molecules

Social media has expanded to reach an unlikely new target: molecules. Scientists at the National Institute of Standards and Technology (NIST) have created networks of molecular data similar to Facebook's recently debuted graph search feature. While graph search would allow Facebook users to find all their New York-living, beer-drinking buddies in one quick search, the NIST-designed networks could help scientists rapidly sift through enormous chemical and biological data sets to find substances with specific properties, for example all 5-ring chemicals with an affinity for enzyme A. The search approach could help speed up the development of new drugs and designer materials.

The NIST team will present their research at the upcoming American Crystallographic Association Meeting, held July 20-24 in Honolulu.

Choosing the Right Words

Molecules don't maintain their own online profiles, so a key challenge for the NIST research team was to develop a standard language for scientists to describe their research subjects. For example, one research group may describe a material's properties as glassy while another team might use the word vitreous, even though the two words have the same meaning, explained Ursula Kattner, a researcher in the Materials Science and Engineering Division at NIST.

July 16, 2013

How cranberries impact infection-causing bacteria

Consuming cranberry products has been anecdotally associated with prevention of urinary tract infections (UTIs) for over 100 years. But is this popular belief a myth, or scientific fact?

In recent years, some studies have suggested that cranberries prevent UTIs by hindering bacteria from sticking to the walls of the urinary tract, thanks to phytochemicals known as proanthocyanidins (PACs). Yet the mechanisms by which cranberry materials may alter bacterial behaviour have not been fully understood.

Now, researchers in McGill University's Department of Chemical Engineering are shedding light on the biological mechanisms by which cranberries may impart protective properties against urinary tract and other infections. Two new studies, spearheaded by Prof. Nathalie Tufenkji, add to evidence of cranberries' effects on UTI-causing bacteria. The findings also point to the potential for cranberry derivatives to be used to prevent bacterial colonization in medical devices such as catheters.

In research results published online last month in the Canadian Journal of Microbiology, Prof. Tufenkji and members of her laboratory report that cranberry powder can inhibit the ability of Proteus mirabilis, a bacterium frequently implicated in complicated UTIs, to swarm on agar plates and swim within the agar. The experiments also show that increasing concentrations of cranberry powder reduce the bacteria's production of urease, an enzyme that contributes to the virulence of infections.

People who eat nuts more than three times a week have reduced risk of dying from cancer or cardiovascular disease

People who eat nuts, particularly walnuts, are more likely to live longer, finds research in BioMed Central's open access journal BMC Medicine. In a longitudinal study, researchers suggest that those who eat nuts more than three times a week have a reduced risk of dying from cancer or cardiovascular disease than non-nut eaters.

The PREDIMED nutrition trial based in Spain looked at the effect on the primary prevention of cardiovascular disease of over 7000 older people (aged 55 to 90) randomized to a Mediterranean Diet supplemented with extra virgin olive oil or nuts, compared to a control group following a low fat diet. In Mediterranean regions, nut consumption is relatively high compared to other countries. People who ate nuts tended to have a lower BMI and smaller waist. They were also less likely to smoke and were more physically active than those who rarely or never ate nuts. Nut eating was associated with a better diet in general as these people ate more vegetables, fruit and fish.

July 12, 2013

Air pollution responsible for more than 2 million deaths worldwide each year, experts estimate

More than two million deaths occur worldwide each year as a direct result of human-caused outdoor air pollution, a new study has found.

In addition, while it has been suggested that a changing climate can exacerbate the effects of air pollution and increase death rates, the study shows that this has a minimal effect and only accounts for a small proportion of current deaths related to air pollution.

The study, which has been published today, 12 July, in IOP Publishing's journal Environmental Research Letters, estimates that around 470,000 people die each year because of human-caused increases in ozone.

It also estimates that around 2.1 million deaths are caused each year by human-caused increases in fine particulate matter (PM2.5) ? tiny particles suspended in the air that can penetrate deep into the lungs, causing cancer and other respiratory disease.

July 10, 2013

5-D optical memory in glass could record the last evidence of civilization

Using nanostructured glass, scientists at the University of Southampton have, for the first time, experimentally demonstrated the recording and retrieval processes of five dimensional digital data by femtosecond laser writing. The storage allows unprecedented parameters including 360 TB/disc data capacity, thermal stability up to 1000°C and practically unlimited lifetime.

Coined as the 'Superman' memory crystal, as the glass memory has been compared to the "memory crystals" used in the Superman films, the data is recorded via self-assembled nanostructures created in fused quartz, which is able to store vast quantities of data for over a million years. The information encoding is realised in five dimensions: the size and orientation in addition to the three dimensional position of these nanostructures.

A 300 kb digital copy of a text file was successfully recorded in 5D using ultrafast laser, producing extremely short and intense pulses of light. The file is written in three layers of nanostructured dots separated by five micrometres (one millionth of a metre).

June 28, 2013

New system uses low-power Wi-Fi signal to track moving humans -- even behind walls

The comic-book hero Superman uses his X-ray vision to spot bad guys lurking behind walls and other objects. Now we could all have X-ray vision, thanks to researchers at MIT's Computer Science and Artificial Intelligence Laboratory.

Researchers have long attempted to build a device capable of seeing people through walls. However, previous efforts to develop such a system have involved the use of expensive and bulky radar technology that uses a part of the electromagnetic spectrum only available to the military.

Now a system being developed by Dina Katabi, a professor in MIT's Department of Electrical Engineering and Computer Science, and her graduate student Fadel Adib, could give all of us the ability to spot people in different rooms using low-cost Wi-Fi technology. "We wanted to create a device that is low-power, portable and simple enough for anyone to use, to give people the ability to see through walls and closed doors," Katabi says.

The system, called "Wi-Vi," is based on a concept similar to radar and sonar imaging. But in contrast to radar and sonar, it transmits a low-power Wi-Fi signal and uses its reflections to track moving humans. It can do so even if the humans are in closed rooms or hiding behind a wall.

June 27, 2013

Solar power heads in a new direction: Thinner

Most efforts at improving solar cells have focused on increasing the efficiency of their energy conversion, or on lowering the cost of manufacturing. But now MIT researchers are opening another avenue for improvement, aiming to produce the thinnest and most lightweight solar panels possible.

Such panels, which have the potential to surpass any substance other than reactor-grade uranium in terms of energy produced per pound of material, could be made from stacked sheets of one-molecule-thick materials such as graphene or molybdenum disulfide.

Pound for pound, he says, the new solar cells produce up to 1,000 times more power than conventional photovoltaics. At about one nanometer (billionth of a meter) in thickness, "It's 20 to 50 times thinner than the thinnest solar cell that can be made today," Grossman adds. "You couldn't make a solar cell any thinner."

June 25, 2013

Quantum interaction: 10,000 times faster than light

How fast do quantum interactions happen? Faster than light, 10,000 times faster.

That's what a team of physicists led by Juan Yin at the University of Science and Technology of China in Shanghai found in an experiment involving entangled photons, or photons that remain intimately connected, even when separated by vast distances.They wanted to see what would happen if you tried assigning a speed to what Einstein called "spooky action at a distance."

They didn't find anything unexpected, but that wasn't the point: in physics, sometimes it's good to be sure. The group published their work on the ArXiv.org, a preprint server for physics papers.

Breastfeeding boosts ability to climb social ladder

Breastfeeding not only boosts children's chances of climbing the social ladder, but it also reduces the chances of downwards mobility, suggests a large study published online in the Archives of Disease in Childhood.

The findings are based on changes in the social class of two groups of individuals born in 1958 (17,419 people) and in 1970 (16,771 people).

The researchers asked each of the children's mums, when their child was five or seven years old, whether they had breastfed him/her.

They then compared people's social class as children -- based on the social class of their father when they were 10 or 11 -- with their social class as adults, measured when they were 33 or 34.
Social class was categorised on a four-point scale ranging from unskilled/semi-skilled manual to professional/managerial.

June 21, 2013

Plants 'seen doing quantum physics'

The idea that plants make use of quantum physics to harvest light more efficiently has received a boost.

Plants gather packets of light called photons, shuttling them deep into their cells where their energy is converted with extraordinary efficiency.

A report in Science journal adds weight to the idea that an effect called a "coherence" helps determine the most efficient path for the photons.

Experts have called the work "a nice proof" of some contentious ideas.