Self-healing paint helps drivers out of a scrape

THE dread that grips every car owner when they pull into a parking space that is slightly too small could soon be prevented by an invention from Japan — a transparent vehicle body paint that repairs scratches on its own.

The encounter with a thorny rose bush, the swipe from a fingernail and even the ravages of an automatic carwash brush will no longer hold any fear for drivers. Within a few hours of the damage occurring, the paint will start to re-form itself over the scratch, and by morning the mark should have disappeared.

The Scratch Guard Coat comes courtesy of the car group Nissan, and will soon be making its debut on the notoriously narrow and scratch-prone roads of Japan. The Japanese company will be offering the special paint as an option on its X-Trail SUV before deciding whether to use the product on its range of cars.

The paint will be offered to customers prepared to pay an extra 52,500 yen (£251) on top of the standard price of the X-Trail, and its makers claim that it will continue to work for about three years. Because of Nissan’s corporate partnership with Renault of France, the product’s success in Japan could mean that the paint soon starts appearing on cars in Europe.

Even if the car is attacked with a Y10 coin — the Japanese vandal’s weapon of choice — the paint should be able to cope with the damage. Within about a week, a Nissan spokesman said, the paint will repair the scratch. “Of course, you could speed the whole process up by pouring some warm water over the affected area — that would probably repair it in a matter of minutes,” he added.

Carmakers have been trying for years to offer their customers some sort of reliable scratch-proofing: successes have been few and far between, and the conventional wisdom has been to develop harder grades of paint to give the surface a basic resistance. The Nissan approach, which it has undertaken with Nippon Paint, its supplier, will push research in the opposite direction.

The result is a transparent, synthetic resin, the high density of which means that it slowly flows back to fill any cut in its surface. The proposed thickness of the coating is about the same as a normal coat of paint, which means that it will repair scratches made to that depth. The paint has been designed to coat dark cars, but Nissan said that there was no reason why the technology could not be used on lighter hues.

Japan’s obsession with cleanliness has sent other corporations in a similar direction. Asahi Glass has produced a self-cleaning window, and Panasonic has produced an air-conditioner in which a miniature robot patrols, collecting dust.

Stem Cells without Side Effects

Last year, researchers announced one of the most promising methods yet for creating ethically neutral stem cells: reprogramming adult human cells to act like embryonic stem cells. This involved using four transcription factor proteins to turn specific genes on and off. But the resulting cells, called induced pluripotent stem (iPS) cells for their ability to develop into just about any tissue, have one huge flaw. They're made with a virus that embeds itself into the cells' DNA and, over time, can induce cancer. Now, scientists at Harvard University have found a way to effect the same reprogramming without using a harmful virus--a method that paves the way for tissue transplants made from a patient's own cells.

The first generation of iPS cells was created using a retrovirus to insert the four transcription factors into skin cells. Because a retrovirus, by definition, inserts itself permanently into its host's DNA, this ensured that the transcription factors were transferred,, but it also led to the propagation of the virus itself. Furthermore, since the virus confers self-renewal capabilities to its new host cell, many believed that the retrovirus might be required for iPS cells to reproduce.

New research by Konrad Hochedlinger and his colleagues at Harvard University, the Harvard Stem Cell Institute, and the MGH Center for Regenerative Medicine shows that a different type of virus--an adenovirus--can make the transfer in mouse cells without permanently integrating itself. The resulting iPS cells can divide indefinitely but show no trace of the virus--just a temporary infection that disappears within a short time. "That means that the four transcription factors themselves are sufficient to induce pluripotency in adult cells," Hochedlinger says.

Many view the creation of genetically unmodified iPS cells as regenerative medicine's magic bullet. The cells are not derived from embryos, so researchers can circumnavigate the ethical gray areas. And if these cells turn out to be as potent as embryonic stem cells, they could be used to help regrow tissues damaged in conditions ranging from paralysis to Parkinson's disease to diabetes. If they can be grown from a patient's own cells, they could furthermore be transplanted without triggering immune rejection.

Until now, however, creating iPS cells without integrated viruses had been a major hurdle for stem-cell researchers. Although Hochedlinger has overcome that hurdle, he says there is still some distance to travel. While retroviral techniques allow scientists to turn about one in every 1,000 skin cells into an iPS cell, the adenovirus is far less efficient: only one in every 10,000 to 100,000 fetal liver cells can be converted. "It may be that people have tried adenoviruses before but missed the iPS cells because the efficiency is so low," Hochedlinger says. "We ourselves tried to use adenoviruses a year ago, and it didn't work."

The team's first attempt had been with skin cells. Upon hearing that liver cells required less viral integration for effective reprogramming, however, they changed their approach.

The efficiency, as described in latest edition of the journal Science, is still incredibly low. Out of 1 million adenovirus-infected cells, the researchers ultimately produced just one stable line of stem cells. But the line was genetically unaltered, and when the cells were implanted in mice, they formed a cluster of cells that had differentiated into multiple tissue types (a standard test for pluripotency). When the researchers injected the cells into mouse embryos, the resulting mice had integrated the stem cells into a number of different types of tissue, including tissue in the brain, lungs, and heart. And mice as old as 13 weeks remained tumor-free.

Until now, iPS cells couldn't be compared to embryonic stem cells, since the effects of the integrated virus were unknown. "It was like comparing apples and oranges," Hochedlinger says. Now, however, the potency of the two cell types can be evaluated head to head. "You can really think about doing this in a human setting now, and about making genetically unmodified human cells for modeling or even for therapy."

The finding already has other stem-cell experts thinking about the possibilities. "The paper represents a major breakthrough in reprogramming research and proves to the field that we can reprogram cells directly without viral contamination," says George Daley, a Harvard biologist and stem-cell researcher who was not involved with the research. "It is a major step towards making clinical transplantation of patient-specific cells feasible."

Hochedlinger and his colleagues are now working to increase the efficiency of their adenovirus technique and to repeat their methods to create human iPS cells. "Once we do that," Hochedlinger says, "we can figure out whether [embryonic stem] cells and unmodified iPS cells are really identical to each other or not. I don't know the answer yet."

Handshake key to landing a job, scientists claim

Research by the University of Iowa found applicants - especially women - with a firm handshake are far more likely to get the job than candidates with a limp grip.

A solid handshake was found to be more important than dress or physical appearance as it set off the interviewer's impression of that person.

"We found that the first impression begins with a handshake that sets the tone for the rest of the interview," said researcher George Stewart, associate professor of management and organizations in the Tippie College of Business, in a statement.

Mr Stewart said this was the first study to quantify the importance of a good handshake in a job interview.

The study, to be published in the Journal of Applied Psychology, was conducted with 98 students at a business school participating in mock job interviews with local business representatives.

The interviewers graded each student's overall performance and employability while five trained handshake experts also scored students on their handshake. The scores were then compared.

Mr Stewart said the researchers found that those students who scored high with the handshake experts were also considered to be the most employable by the interviewers and seen as having more extroverted personalities and greater social skills.

The students with limp handshakes were judged to have less gregarious personalities and were less impressive.

We probably don't consciously remember a person's handshake or whether it was good or bad," Stewart said. "But the handshake is one of the first nonverbal clues we get about the person's overall personality, and that impression is what we remember."

The key to a good handshake? A complete, firm grip, eye contact and a vigorous up-and-down movement, said Stewart.

It is women who may benefit more than men if they present a "strong and complete grip when they shake hands".

The report built on previous research by the University of Alabama that showed that women who were more liberal, intellectual and open to new experiences were found to have the a firmer handshake.