Scientists claim to have discovered a new type of stem cells responsible for creative thinking and memories in humans.

Researchers at The Scripps Research Institute identified a stem cell population that may give birth to neurons which play a key role in abstract thought and creativity.

The finding also paves the way for production of these neurons in culture, a first step towards developing better treatments for cognitive disorders like schizophrenia and autism.

The cells were found in embryonic mice, where they formed the upper layers of the brain's cerebral cortex. In humans, the same brain region allows abstract thinking, planning for the future and solving problems. Previously it was thought that all cortical neurons - upper and lower layers - arose from the same stem cells, called radial glial cells (RGCs).

The new research shows that the upper layer neurons develop from a distinct population of diverse stem cells. "Advanced functions like consciousness, thought and creativity require quite a lot of different neuronal cell types and a central question has been how all this diversity is produced in the cortex," Dr Santos Franco, member of the US team from the Scripps Research Institute said.

"Our study shows this diversity already exists in the progenitor cells." said Franco. In mammals, the cerebral cortex is built in onion-like layers of varying thickness.

The thinner inside layers host neurons that connect to the brain stem and spinal cord to regulate essential functions such as breathing and movement.

The larger upper layers, close to the brain's outer surface, contain neurons that integrate information from the senses and connect across the two halves of the brain.

Higher thinking functions are seated in the upper layers, which in evolutionary terms are the "newest" parts of the brain.

"The cerebral cortex is the seat of higher brain function, where information gets integrated and where we form memories and consciousness," said the study's senior author Ulrich Mueller. The new research is published in the journal 'Science'.

That the law is an ass is almost a truism. But few understand that the law is often turned into an ass by its literal interpretation. This is exactly what is preventing the country's first international kidney swap transplant from taking place in Mumbai's Hinduja hospital and BSES MG hospital.

The matter is simple. Two women, one from Rajasthan and the other from Kenya, are in a position to save the life of a member of the other's family by donating a kidney. Both families are keen on the swap and doctors are ready to perform the operation. The hitch: the stubborn Rajasthan government, whose transplantation committee, which needs to give the go-ahead for the operation, is refusing to do so citing the Transplantation of Human Organs Act, 1994. The act prohibits the transplantation of a vital organ from an Indian national in a foreign patient.

The act was passed to prevent the then rampant sale of kidneys by poor Indians to wealthy foreigners for money. It obviously does not matter to Rajasthan government officials that in the case in question, there is no exchange of money involved and no exploitation of a poor Indian by a wealthy foreigner. If anything, there is a happy ending in store for both families.

The Universal Declaration of Human Rights, which has been accepted by all countries, including India, clearly says the law cannot supersede life. Laws are made by human beings for the betterment of society and cannot become impediments to someone's right to life. The sooner the obstinate government officials understand this basic concept and clear the operation, the better it is for everyone, including the families involved.

The raw images sent back by Mars rover Curiosity has revealed that the crater where it landed looks remarkably Earth-like, scientists said.

"The first impression that you get is how Earth-like this seems looking at that landscape," said chief scientist John Grotzinger of the California Institute of Technology.

It provided the best view so far of its destination since touching down Sunday night after nailing an intricate choreography. During the last few seconds, a rocket-powered spacecraft hovered as cables lowered Curiosity to the ground.

In the latest photos, Curiosity looked out toward the northern horizon. Nearby were scour marks in the surface blasted by thrusters, which kicked up a swirl of dust. There were concerns that Curiosity got dusty, but scientists said that was not the case.

"We do see a thin coating of dust, but nothing too bad," said Justin Maki, imaging scientist at NASA's Jet Propulsion Laboratory, which manages the USD 2.5 billion mission.

Scientists were giddy about the scour marks because they exposed bedrock below information that should help scientists better understand the landing site.

Since landing, Curiosity has zipped home a stream of low-resolution pictures taken by tiny cameras under the chassis and a camera at the end of its robotic arm, which remained stowed. It also sent back a low-quality video glimpsing the last 2 1/2 minutes of its descent.

The rover successfully raised its mast packed with high-resolution and navigation cameras. With the mast up, it can begin its shutterbug days in force including taking a 360-degree color view of its surroundings as early as today.

Grotzinger said he was struck by the Martian landscape, which appeared diverse. There seemed to be harder material underneath the gravelly surface, he said.

"It kind of makes you feel at home," he said. "We're looking at a place that feels really comfortable."

Mars, of course, is very different from Earth. It's a frigid desert constantly bombarded by radiation. There are geological signs that it was a warmer and wetter place once upon a time. One of the mission's goals is to figure out how Mars transformed.

Weight training helps to prevent type 2 diabetes in men, research suggests.

Researchers found regular weights reduced the risk by up to a third, in the study of more than 32,000 men published in the Archives of Internal Medicine journal.

It is already well known that regular exercise can prevent the disease.

But the report is considered important as weights provides an alternative to aerobic exercises such as running for people who are not so mobile.

Researchers from Harvard School of Public Health in the US and the University of Southern Denmark followed the men over an 18-year period, during which time nearly 2,300 developed the condition.
'Difficulty'

They found 30 minutes of weights a day, five times a week could reduce the risk of diabetes by 34%.

But they also reported that even less regular exercise - up to an hour a week - had an impact, cutting the risk by 12%.

Nonetheless, aerobic exercise was still found to be slightly better with regular activity halving the risk.

The two combined had the greatest effect, reducing it by up to 59%, the study found.

Lead author Anders Grontved said: "Many people have difficulty engaging in or adhering to aerobic exericse.

"These new results suggest that weight training, to a large extent, can serve as an alternative."

It is not clear if the same results would be found with women.

Scientists might be a bit sniffy about this latest research, but a nasal spray containing a hormone can help bring happiness to warring couples living together.

A study has shown that breathing in a compound containing oxytocin makes women calmer and friendlier and men more sensitive and positive during arguments.

Dubbed the 'cuddle drug', oxytocin is naturally made in the body and is involved in sex, sexual attraction, trust and confidence.

It is released into the blood during labour - triggering the production of breast milk - and floods the brain during breastfeeding, helping mother and baby bond.

The research, reported in the journal Social Cognitive and Affective Neuroscience, looked at how the hormone affects stress and the autonomic nervous system during disagreements between couples.

When there is an argument, there is an increased heart rate and higher blood pressure.

Forty-seven couples, aged 20 to 50, were involved in the experiment at Zurich University. They were either married or had cohabited for at least a year.

They chose a topic which caused conflict in their relationship before having five puffs of oxytocin or a placebo spray. After 45 minutes they were left alone in a room and filmed discussing the contentious issue.

Researchers monitored the participants, taking saliva swabs to check for compounds showing how the nervous system was working.

The findings revealed that compared to those who took the placebo, women who sniffed oxytocin were more friendly, less demanding while men were more positive and more likely to engage.

There was a drop in nervous system activity for women while in men it went up.

According to the researchers, women tend to show demanding behaviour more frequently and men tend to withdraw. 'In out study, oxytocin might have driven quiescence in women and social salience and approach behaviour in men,' the journal reported.

Nottingham University professor Kavita Vedhara believes the study has shown that oxytocin reduces women's 'emotional and physiological arousal following verbal conflict' while the opposite happens to men.

Scientists have previously found that a man's libido was improved when he sniffed a spray containing oxytocin.

Research at the University of California reported that a married man who sniffed the spray twice a day saw a considerable improvement in his sexual performance.

His libido went from 'weak to strong' while arousal levels went from 'difficult to easy.'

In an unusual scientific experiment, couples who sprayed themselves with a compound containing the hormone oxytocin before they discussed contentious issues then behaved more positively.

Women were less emotionally aroused and men more aroused after using the spray. According to researchers, the women who took part in the tests were more friendly, less demanding and less anxious, while men were more aware of social cues, more positive, and more likely to engage.

Oxytocin is produced mainly in the hypothalamus region of the brain. It had been studied in women because it is released during labour to dilate the cervix, boost contractions and to trigger the release of milk in the breasts.

In the new study, reported in the journal Social Cognitive and Affective Neuroscience, researchers looked at its effects on stress and the activity of the autonomic nervous system during disagreements between couples.

This part of the nervous system automatically regulates organs of the body, and research has shown it is more active during conflict between couples, leading to increased heart rate and blood pressure.

Forty-seven couples, aged 20 to 50, who were married or had been cohabiting for at least a year, took part in the study at the University of Zurich. Couples chose a topic to discuss about which they continually disagreed, and then self-administered five puffs of either the oxytocin or a placebo spray.

Forty-five minutes later, each couple was left alone in a room and filmed while they talked about the subject that usually rubbed them up the wrong way.

At various times during the experiments, the researchers took saliva swabs to check for compounds that show how the nervous system is working.

The results showed that, compared to those who had sniffed the placebo, women who had the oxytocin spray experienced a drop in nervous system activity, whereas in the men it went up. The men displayed increased positive behaviour; the women became more friendly.

In general, the researchers say, women tend to show demanding behaviour more frequently, while men tend to withdraw: 'In our study, oxytocin might have driven quiescence in women and social salience and approach behaviour in men.''

Kavita Vedhara, professor of health psychology at Nottingham University, said the findings were very interesting: 'We are much clearer about the biological role of oxytocin in women, but these data suggest it could have significant effects in men.

What they have shown is that oxytocin appears to reduce women's emotional and physiological arousal following verbal conflict, but that the drug has the opposite effect on men, increasing both their emotional and physiological arousal.

It is not clear if the increased emotion in men was always positive, but it was certainly associated with more positive behaviours during the conflict situation.'

The researchers now want to look further into the possible benefits of oxytocin on warring couples.

'It is possible that the effect simply produced short-term changes in how couples interact with each other,' said Professor Vedhara.

'This might help to take the heat out of an argument. But whether it helps to resolve the issues that lead to the arguments is not clear.'