Science Sunday #9
Posted by Don McLenaghen on August 14, 2011
– and on the seventh day we learn.
Each week I hope to give a synopsis of the interesting science stories I have heard on my plethora of science podcasts I listen to each week plus anything I pick up scanning the inter-web. This week’s top stories:
Darkest Known Exoplanet: Alien World Is Blacker Than Coal –
TrES-2b orbits the star GSC 03549-02811 at a distance of only 5 million kilometers (the earth is 150 m km from the Sun); they are located about 750 light years away in the direction of the constellation of Draco the Dragon. Measurements show that TrES-2b reflects less than one percent of the sunlight falling on it, making it blacker than coal or any planet or moon in our solar system.
Research Reveals Genetic Link to Human Intelligence –
Previous studies on twins and adopted people suggested that there is a substantial genetic contribution to thinking skills, but a new study — published in the journal Molecular Psychiatry — is the first to find a genetic contribution by testing people’s DNA for genetic variations.
Dr Pendleton, who led the Manchester team in the Centre for Integrated Genomic Research, said: “This is the first reported research to examine the intelligence of healthy older adults and, using a comprehensive genetic survey, we were able to show a substantial genetic contribution in our ability to think.
“The study confirms the earlier findings of the research in twins. However, that research could not show which genes were or were not contributing to cognitive ability. Our work demonstrates that the number of individual genes involved in intelligence is large, which is similar to other human traits, such as height.
How we see moving object one at a time –
Although our eyes record the word as millions of pixels, “the visual system is fantastic at giving us a world that looks like objects, not pixels,” It does this by grouping areas of the world with similar characteristics, such as color, shape, or motion says Northwestern University psychologist Steven L. Franconeri.
The process is so seamless that we feel we’re taking it all in simultaneously. But this, says a new study by Franconeri and his colleague Brian R. Levinthal, is “an illusion.” Instead, they say, that for some types of grouping, the visual system is limited by its ability to perceive only one group at a time. The findings were just published in Psychological Science, a journal of the Association for Psychological Science.
How does this grouping work? Say you’re looking at a crowded street, with cars going every which way. Your view of each individual car is partially blocked, so that you actually see multiple “pieces” of each. Yet because those pieces move with the same direction of motion, grouping by “common fate” helps you perceive whole cars. You might feel that this grouping is happening for all the cars at once — but Levinthal and Franconeri suggest otherwise.
“People were surprisingly slow,” says Franconeri. As participants were asked to make decisions involving more groups, they took more and more time. They were limited by their one-at-a-time visual systems, which, he says, “needed to flip through the groups, at a rate of about 10 per second.”.
Were the London Riots a Spontaneous Mass Reaction or a Rational Response? –
A key misunderstanding, however, seems to pervade popular thinking: that mobs are irrational and are driven to violence by a few bad apples. In fact, the scientific evidence shows that individuals in mobs do behave rationally, although not always wisely.
Many official and media accounts place the blame on “a violent few” who swept thousands of others into a destructive frenzy. These analyses echo the 1896 work of Gustave Le Bon, who published The Crowd: A Study of the Popular Mind. “Crowds, after a period of excitement, enter upon a purely automatic and unconscious state, in which they are guided by suggestion,”
That idea, however, is a myth; social psychologists debunked it in the 1980s. “When people form a psychological group, what happens isn’t that they lose a sense of identity but that they think of themselves in terms of group membership,” explains social psychologist Stephen Reicher of the University of Saint Andrews in Scotland. “Riots are the endpoint of a very long and entrenched process of social sense-making,” Reicher says. “When an event comes along that clicks in perfectly to this broader social understanding, then suddenly it’s much more likely to make you see yourself as a group member.”
“One thing science does tell us is that we can’t understand it if we treat it as irrational [or] if we think of these people as a gathering of people with individual predispositions to violence,” says Clifford Stott, a social psychologist at the University of Liverpool. Stott’s previous research has demonstrated that the unilateral force that is sometimes used against a mostly nonviolent crowd can backfire, cementing the unity of the group against the now-violent authorities. This newly combative dynamic can change what’s considered acceptable group behavior for everyone and leave group members with an intoxicating feeling of empowerment
Is This How Simple Life Got Complicated? –
A new study has created an analog of what researchers think the first multicellular cooperation might have looked like, showing that yeast cells — in an environment that requires them to work for their food — grow and reproduce better in multicellular clumps than singly.
The study, published August 9 in the online, open access journal PLoS Biology, used the yeast Saccharomyces cerevisiae, which is commonly used in brewing and bread-making and has long been used by scientists as a model organism for understanding single-celled life..
A team of researchers, led by Harvard professor Andrew Murray, found that cells of brewer’s yeast that clumped together were able more effectively to manipulate and absorb sugars in their environment than were similar cells that lived singly. The experiments showed that in environments where the yeast’s sugar food source is dilute and the number of cells is small, the ability to clump together allowed cells that otherwise would have remained hungry and static to grow and divide.
Artificial anal sphincter could limit bowel incontinence –
Another milestone for custom-crafted transplants: the world’s first lab-built sphincters. The breakthrough offers hope to countless people who have become incontinent through damage to their own anal sphincters.
“Successful development of a bioengineered physiologic internal sphincter would represent a distinct advantage over currently available mechanical artificial sphincters,” says Robert Madoff, who researches colon and rectal surgery at the University of Minnesota Medical School in Minneapolis.
Those most likely to benefit from the new research are women who have been injured during childbirth and the elderly. Bitar says that the same technique could be adapted to make other important sphincters, such as those that hold in urine.
Monkeys did not gain big brains by shrinking guts –
DID shrinking guts and high-energy food help us evolve enormous, powerful brains? The latest round in the row over what’s known as the ‘expensive tissue hypothesis’ says no.
The hypothesis has it that in order to grow large brains relative to body size, our ancestors had to free up energy from elsewhere. In the Proceedings of the Royal Society B, Kari Allen and Richard Kay of Duke University in Durham, North Carolina, turned to New World monkeys to explore the hypothesis. Previous studies offer a wealth of data on the monkeys’ diets and show that their brain size varies greatly from species to species. But when the pair controlled for similarities between related species, they found no correlation between large brains and small guts.
In the scientific record books, Tegon joins a red fluorescent puppy named Ruppy and Mr. Green Genes the cat as all being human-modified animals that can glow.
Electronic ‘Skin’ Monitors –
Rogers and his colleagues at Urbana-Champaign and other institutions in the United States, Singapore, and China have come up with a form of electronics that almost precisely matches skin’s mechanical properties. Known as epidermal electronics, they can be applied in a similar way to a temporary tattoo: you simply place it on your skin and rub it on with water. The devices can even be hidden under actual temporary tattoos to keep the electronics concealed.
Applications for monitoring premature babies and neonatal care are interesting. Babies don’t do well when they’re wired up to bulky patches so non-invasive monitoring devices have a lot of value. This technology could also be useful for human-machine interfaces through the throat for people with problems in their larynx, and more generally, prosthetic control for disabled people.
One major downside is that the continual shedding of skin cells means that the patch falls off after a few days. The researchers are looking for ways around this, so they can be worn for months at a time.
Uniquely Canadian –
A new report in the journal BMC Medical Informatics and Decision Making by Dr. Khaled El Emam, the Canada Research Chair in Electronic Health Information at the University of Ottawa and the Children’s Hospital of Eastern Ontario Research Institute, suggests that Canadians can be uniquely identified from their date of birth, postal code, and gender. This means if this triad of data exists in any database, even if it has no names or other identifying information, it would be possible to determine the identity of those individuals.
“The findings are important because they offer yet another onion skin to peel back in the overarching dialogue about individual privacy rights. We need to continuously evaluate these risks to privacy, and put in place measures to protect anonymity, whether technological or policy-based. Failure to do so will result in a public unwilling for their health data to be used for secondary purposes, such as health research,” said Dr. El Emam. “Take for example, if only a three character postal code is combined with the full date of birth, close to 80% of the population is unique — or easily identifiable. I suspect this will surprise most people.”