Whether it’s a curled lip or a keen cheekbone, we all make quick social judgements based on strangers’ faces.

Now scientists have modelled the specific physical attributes that underpin our first impressions.

Small changes in the dimensions of a face can make it appear more trustworthy, dominant or attractive.

The results, published in the journal PNAS, could help film animators or anyone looking to create an instant impression on a social network.

Dr Tom Hartley, a neuroscientist at the University of York and the study’s senior author, said the work added mathematical detail to a well-known phenomenon.

“If people are forming these first impressions, just based on looking at somebody’s face, what is it about the image of the face that’s giving that impression – can we measure it exactly?”

Positive first impressions are especially important in a world dominated by social media, from LinkedIn to Tinder.

Dr Hartley sees the commercial potential in applying his numerical model to the photos people use to present themselves online. “It’s obviously potentially very useful,” he told the BBC.

To make the calculations, each of 1,000 face photos from the internet was shown to at least six different people, who gave it a score for 16 different social traits, like trustworthiness or intelligence.

Overall, these scores boil down to three main characteristics: whether a face is (a) approachable, (b) dominant, and (c) attractive.

By measuring the physical attributes of all 1,000 faces and putting them together with those scores, Dr Hartley and his team built a mathematical model of how the dimensions of a face produce those three impressions.

The next step was to get the computer to extrapolate. Using their new model, the team produced cartoon versions of the most (and least) approachable, dominant and attractive faces – as well as all the possibilities in between.

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Skin cells from humans can be revamped into pro-clotting cells called platelets, according to a study published on November 22 in theJournal of Experimental Medicine. Patients with diseases causing thrombocytopenia — platelet deficiency — often require repeated transfusions with platelets obtained from healthy donors.

Doctors have taken an important step toward a long-sought goal: harnessing a person’s own immune system to fight cancer.

An article published Thursday in the journal Science describes the treatment of a 43-year-old woman with an advanced and deadly type of cancer that had spread from her bile duct to her liver and lungs, despite chemotherapy.

Researchers at the National Cancer Institute sequenced the genome of her cancer and identified cells from her immune system that attacked a specific mutation in the malignant cells. Then they grew those immune cells in the laboratory and infused billions of them back into her bloodstream.

The tumors began “melting away,” said Dr. Steven A. Rosenberg, the senior author of the article and chief of the surgery branch at the cancer institute.

The woman is not cured: Her tumors are shrinking, but not gone. And an experiment on one patient cannot determine whether a new treatment works. But the report is noteworthy because it describes an approach that may also be applied to common tumors — like those in the digestive tract, ovaries, pancreas, lungs and breasts — that cause more than 80 percent of the 580,000 cancer deaths in the United States every year.

Dr. Rosenberg’s patient, Melinda Bachini, now 45, a paramedic in Billings, Mont., who is the mother of six children, said that without the cell treatment, “honest, I don’t know that I would be here.”

Dr. Rosenberg agreed, saying that in April 2012, when Ms. Bachini received the first immune treatment, her life expectancy was probably a matter of months.

Related techniques involving immune cells have brought lasting remissionsfor people with leukemia, a blood cancer, and the aggressive skin cancermelanoma. But until now researchers had not found a way to use the cells against the so-called solid tumors that cause so many deaths.

Other researchers said the treatment used by Dr. Rosenberg’s team, known as adoptive cell therapy, had promise for these common cancers. But they also cautioned that the report was early and based on just one patient.

Dr. Carl June, who directs similar research at the University of Pennsylvania, said the research addressed an important issue by showing that adoptive cell therapy could have an effect on commonly lethal solid tumors.

Another expert, Dr. Michel Sadelain of the Memorial Sloan-Kettering Cancer Center in New York, said the report showed that carefully selected immune cells could be a powerful tool against bile-duct cancer. But he also said it was too soon to tell if the same approach would work for other patients or could be scaled up to treat all those who might need it.

Dr. Rosenberg acknowledged that there were limitations: The technique required highly sophisticated techniques in immunology, and produced a treatment tailored to only one patient. He said his team was working around the clock to streamline the process, and added, “Potentially, if we could reduce the complexity, it’s something that could get out into common usage eventually.”

Researchers have hoped for decades to find some unique marker on cancer cells, something not present on healthy cells, that could be used as a target so that cells of the immune system could home in on it and leave the good ones alone.

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Engineers have developed a prototype tablet display that compensates for an individuals’ vision problems.

The system uses software to alter the light from each individual pixel on the screen, based on the person’s glasses prescription.

The researchers also added a thin plastic pin hole filter to enhance the sharpness of the image.

The team say the technology could help millions who need corrective lenses to use their digital devices.

Around one person in three in the UK suffers from short-sightedness or myopia. In the US, around 40% while in Asia it is more than half the population.

The authors of this latest study say their prototype offers “significantly higher contrast and resolution compared to previous solutions”.

Follow the light

The team from the University of California, Berkeley, working with colleagues at Massachusetts Institute of Technology (MIT), developed an algorithm that adjusts the intensity of each direction of light that emanates from a single pixel in an image, based on the user’s specific visual impairment.

Their prototype used an iPod, with a printed pinhole mask attached to the screen. To check the images, the researchers used a digital single-lens reflex (DSLR) camera which was set up to simulate a person who was farsighted.

The altered images from the iPod appeared sharp and clear to the camera, showing that the prototype was effective in correcting this sight issue.

“The significance of this project is that, instead of relying on optics to correct your vision, we use computation,” said lead author Fu-Chung Huang. “This is a very different class of correction, and it is non-intrusive.”

The research team believe that their idea, when refined further, could be of benefit to people who suffer from more difficult-to-treat vision issues.

“We now live in a world where displays are ubiquitous, and being able to interact with displays is taken for granted,” said Prof Brian Barsky, from UC Berkeley, the project leader.

“People with higher order aberrations often have irregularities in the shape of the cornea, and this irregular shape makes it very difficult to have a contact lens that will fit.

“In some cases, this can be a barrier to holding certain jobs because many workers need to look at a screen as part of their work. This research could transform their lives.”

Battery question

It should be stressed that while the research is at a very early stage, the engineers behind it the approach believe it has great potential, in the field of visual correction and beyond.

They envisage displays that users with different visual problems can view at the same time and see a sharp image.

“In the long run we believe that flexible display architectures will allow for multiple different modes, such as glass free 3D image display, vision corrected 2D image display and combinations of vision corrected and 3D image displays,” the authors write.

No consideration has been given, at this stage, to the impact such a system might have on the battery life of digital devices. This could also be an important factor going forward.

The research will be presented at an international conference on computer graphics called SIGGRAPH, in Vancouver in August.

A new study shows that schizophrenia is caused, at least in part, by large, rare structural changes in DNA referred to as copy number variants (CNVs) – not the tiny, single letter alterations (single nucleotide polymorphisms (SNPs) that scientists have pursued for years.

HIV has resurfaced in a child who was presumed cured of the virus. The discovery spotlights limits in detecting the clandestine germ and raises questions about whether HIV can ever truly be cured, experts say.

The child was born HIV-positive in 2010 and received treatment with standard antiretroviral drugs. The patient’s therapy was unexpectedly interrupted 18 months later. But the virus didn’t return to detectable levels, leading scientists to declare last year that the child was “functionally cured” (SN: 4/6/13, p. 14).

On July 10, researchers at the U.S. National Institute of Allergy and Infectious Diseases announced that the virus had resurfaced in the child’s blood after nearly four years of dormancy.

“What we’ve learned is that you can never be fully certain of HIV eradication,” says Daniel Kuritzkes, a Harvard virologist, who wasn’t involved in the case.

He explains that surveillance tools lack the sensitivity needed to find HIV in its many hideouts (SN: 7/26/14, p.12). The virus lives in immune cells called memory T cells that circulate in the blood. Doctors can easily collect and scan these cells for HIV. But
memory T cells also filter into lymph nodes or deep into organs, where the cells become inactive and HIV becomes invisible to standard detection. The virus waits until the T cell reawakens, at which point HIV once again replicates using the cell’s machinery.

Memory T cells live as long as eight years, so the potential for viral reemergence always existed for this child, says Marc Foca, an HIV specialist at the Morgan Stanley Children’s Hospital in New York City. “Most experts weren’t fully convinced that this baby was actually cured,” he says.

The child has gone back on antiretroviral treatment, and her viral levels have dropped.

The family seemed to defy the rules of genetics.

When Meriel M. McEntagart, a geneticist at St. George’s University of London, met the family in May 2012, she suspected that three of the children had a rare genetic disorder called Smith-Magenis syndrome. They had many of the symptoms of the disease, such as trouble sleeping through the night. Dr. McEntagart confirmed that diagnosis with a genetic test. The children were all missing an identical chunk of a gene known as RAI1.

One of the children had a different father from the other two, and so the mother could be the only source of their altered gene. But when Dr. McEntagart ran a standard blood test on the mother, the results were not nearly so straightforward: The woman had a normal version of RAI1.

Dr. McEntagart and her colleagues suspected that the answer to this puzzle was that the mother was a genetic mosaic.

Dr. McEntagart said that she suspected that the mother she encountered had a normal version of RAI1 in some cells but an altered version in other cells, including her eggs.

“We wanted to understand if there was a way to demonstrate that she was a mosaic,” Dr. McEntagart said.

Dr. McEntagart got wind that researchers at Baylor College of Medicine in Houston were developing new methods for pinpointing mosaics, and they confirmed that the mother was indeed a mosaic. Some of her cells carried the Smith-Magenis syndrome mutation.

Scientists have known about mosaicism for decades, but they’ve studied it mostly on a case-by-case basis. As a result, it has been hard to tell if the kind of mosaicism Dr. McEntagart encountered was a fluke, or if it was common enough to be medically important.

In a study released Thursday in the American Journal of Human Genetics, the Baylor team and its colleagues describe the biggest search for cases in which mosaic parents passed down disease-causing mutations to their children. It turns out to be far from a fluke.

“This happens a surprising amount of the time,” said Chad A. Shaw, a co-author of the new study.

Michael Snyder, a geneticist at Stanford University who was not involved in the study, said it showed that mosaicism could have a significant effect on not just people’s own health, but on their children as well.

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