Thursday 27 August 2009
The Britsih Science Festival
The week long, jam-packed programme has loads of events for everyone. Each year thousands of people join us for talks, plays, debates, hands-on activities and more. This year the Festival is hosted by the University of Surrey in Guildford from 5-10 September with events taking place across Surrey.
The Science: [so what? so everything] team will doing science demonstrations and handing out goodies on 5th and 6th September, at the family weekend.
Please visit The Britsih Science Association for more.
Friday 21 August 2009
Study: Monkeys share human preference for imitation
A new study shows capuchin monkeys prefer humans whose behavior mimics theirs, a trait they share with humans, scientists say.
This capuchin monkey lives in the Amazon rain forest of northern Brazil.
Research conducted by the National Institutes of Health in cooperation with two Italian institutions examined how monkeys reacted to two types of humans -- ones who copied their actions and ones who didn't.
"If one person imitates what a monkey does, and the other person does not imitate, the monkey prefers to spend more time in front of the person that imitated them," said Dr. Annika Paukner at the National Institutes of Health offices in Poolesville, Maryland.
Research has shown for some time that humans prefer to interact with others who act like them, and people have a subconscious tendency to imitate others. Paukner told CNN the new study shows it is more than just a human trait.
"It's something that's quite old and something very, very basic. It's not just for us sophisticated humans," she said.
In the study, a capuchin monkey was given a wiffle ball and was allowed to interact with a pair of researchers -- one who, using another ball, attempted to mimic the action of the monkey, and one who deliberately acted in a different way.
Monkeys in the study consistently spent more time interacting with the imitators. They also more readily accepted food and trinkets from the mimicking humans, even when the non-imitators offered the same rewards.
According to the report, the new findings indicate an evolutionary link to the way humans form friendships and create social connections. It also eventually may help people who struggle in social situations, including those suffering from autism.
"Observing how imitation promotes bonding in primates may lead to insights in disorders in which imitation and bonding are impaired," Dr. Duane Alexander of the National Institute of Child Health and Human Development said in a written statement.
Autism spectrum disorders are often marked by an inability to recognize and process social cues that are clear to others.
The National Research Council in Rome and the University of Parma conducted the research along with the National Institutes of Health.
The full report appears in this week's edition of the journal Science.Visit CNN for more.
Thursday 20 August 2009
Fabricated genetic fingerprints and the limits of forensic science
In CSI, the phenomenally successful television show about forensic science, DNA evidence is usually presented as something of a clincher. It's often said that a crime-scene sample that matches a suspect's genetic fingerprint leaves only a one in a million chance that he or she is innocent, and this sort of evidence is often among the most likely to convince judges and juries.
The police and the Home Office see it as so valuable and reliable that they want the Police National DNA Database to retain samples from people who are arrested but never convicted, even though the European Court of Human Rights has ruled this unlawful.
Since it was developed by Sir Alec Jeffreys in 1984, DNA fingerprinting has indeed helped to solve thousands of crimes, both convicting the guilty and exonerating the innocent. But valuable as it is, it is no more infallible than any other investigational tool. A fresh reason why has been highlighted this week by the New York Times, with a story suggesting that genetic evidence can easily be faked.
A team from an Israeli company called Nucleix, led by Dan Frumkin, has fabricated samples of blood and saliva that were provided by one person, but which carry the DNA of another. The scientists, whose work is published in the journal Forensic Science International: Genetics, also showed they can build DNA samples to match anybody whose genetic code is recorded in a database, without even obtaining any tissue.
The implications sound pretty worrying. An enterprising criminal could cover his tracks, and frame someone else, by collecting cells from a glass they had used and turning it into a saliva or blood sample carrying the innocent person's DNA. An unscrupulous policeman with access to the DNA database might even be able to use its contents to create evidence that would implicate a suspect. The techniques involved, Frumkin claimed, are not particularly complicated. "You can just engineer a crime scene," he told the NYT. "Any biology undergraduate could perform this."
It's quite true that DNA evidence is potentially open to manipulation in this manner. I'm not entirely convinced, though, that this paper undermines its value in criminal investigations quite as extensively as it might seem.
For a start, as The Register notes, it's already perfectly plausible for a criminal to plant hair from another person at a crime scene, without recourse to a laboratory. Frumkin's claims about the simplicity of making DNA evidence notwithstanding, few criminals will have the resources or know-how to do it. And in many cases, their own DNA will be more abundant than the evidence they plant -- a rapist, for example, will still be vulnerable from the semen he leaves behind him.
Frumkin's company, incidentally, is trying to sell police forces a system it has designed for telling manufactured DNA apart from the real thing, by analysing methylation patterns (which are involved in switching genes on and off). It clearly has an interest in promoting the idea that this is going to be a major problem.
What this research does highlight, however, is the danger of treating DNA evidence as something special. Important as it can be, it can only ever be one element of the evidence that builds a case beyond reasonable doubt -- and that applies whether or not it is easy to fake.
The one-in-a-million probability of a chance match is a good place to start. The basic maths are correct enough, but that doesn't mean that the chances that a suspect who matches that sample is innocent are also one in a million. All that a match does is to place that person at the crime scene -- and most crime scenes will be littered with DNA from perfectly innocent people. Absent further evidence pointing to guilt, that should never be sufficient to convict.
What matters is the context in which DNA is found, and the supporting evidence. DNA from semen found on a rape victim, or skin cells under the fingernails of a murder victim, is one thing. A few hairs on the floor of a corner shop that has been robbed are quite another.
However simple it is to fabricate DNA evidence, it should never be trivial to plant it in a properly convincing way. So long as we see genetic fingerprints as one tool among many for solving crimes, and do not exaggerate what they can tell us, we should be reasonably safe from miscarriages of justice.
Visit Times online for more informationWednesday 19 August 2009
Coordination Needed to Support Green Fingered Youths
Young people working on conservation projects are often coerced into "grunt" activities like digging holes or picking up litter and gain little from environmental volunteering, according to research at the University of Exeter.
The project, which was funded by the Economic and Social Research Council (ESRC), found that many young volunteers travelled long distances from cities to short-term projects in rural areas and felt they were being punished for being disruptive or naughty at school. They saw the conservation work as having no relevance to their future employment, or educating them on green issues.
'The problem lies in the mismatch between youth services and environmental education,' says Dr Michael Leyshon, who led the project. 'Environmental conservation is largely organised by people with a background in environmental science, but no training in youth work and youth workers have no training in conservation. The result is that young people and the environment both lose out. We need more coordination in the voluntary sector and an effective interface with youth services.'
Dr Leyshon acknowledges that many young people do volunteer because they enthusiastic about conservation, but he says that environmental skills should not be seen in isolation. 'There is a need for more certificated courses, in a variety of 'rural' skills, such as those run by the National Trust. But we also need to think more holistically, and try to connect skills-building with supporting local transport, training and business support as part of an overall regeneration policy.'
The report says that properly managed volunteer work in conservation could offer young people the opportunity to live and work locally. Latest figures suggest that each year 100,000 young people are leaving rural areas of England.
'Managing the countryside for the purposes of environmental sustainability is one of the few sectors of the rural economy that can offer the soft skills, like the ability to work in a team as well as the practical skills that could be useful in many other kinds of jobs,' Dr Leyshon explains. 'Environmental projects should be part of mainstream education, not somewhere for excluded kids and youth offenders to take a bit of exercise in a "green gym".'
Tuesday 18 August 2009
World's smallest laser unveiled
The world's smallest laser, contained in a silica sphere just 44 nanometres across, has been unveiled. At about 10 times smaller than the wavelength of light, however, this is no ordinary laser, it is the first ever 'spaser'.
Whereas a laser amplifies light, using a mirrored cavity to intensify it, a spaser amplifies surface plasmons — tiny oscillations in the density of free electrons on the surface of metals, which, in turn, produce light waves.
The spaser could be used as a light source for scanning near-field optical microscopes, which can resolve details beyond the reach of standard light microscopy, and in nanolithography, to etch patterns much smaller than the width of a human hair. The device also opens the door to nanoscale circuits that could process information thousands of times faster than the microelectronic chips inside today's computers.
"This work has utmost significance," says Mark Stockman of Georgia State University in Atlanta, who with David Bergman of Tel Aviv University in Israel proposed the spaser concept in 20031. "The spaser is the smallest possible quantum amplifier and generator of optical fields on the nanoscale — without it, nanoplasmonics is like microelectronics would have been without a transistor."
Go to Nature.com for the full article
Friday 14 August 2009
Mars, Methane And Mysteries: Red Planet May Not Be As Dormant As Once Thought
“Methane was a surprise, we were not expecting that,” says Agustin Chicarro, ESA Mars Lead Scientist. The reason is that on Earth much of the methane in our atmosphere is released by evolved life forms, such as cattle digesting food. While there are ways to produce methane without life, such as by volcanic activity, it is the possible biological route that has focused attention on the discovery.
Thursday 13 August 2009
So why do flamingos stand on one leg?
The question is asked by zoo visitors and biologists alike, but while numerous theories abound, no-one has yet provided a definitive explanation.
Now after conducting an exhaustive study of captive Caribbean flamingos, two scientists believe they finally have the answer.
Flamingos stand on one leg to regulate their body temperature, they say.
Matthew Anderson and Sarah Williams are comparative psychologists based at Saint Joseph's University in Philadelphia, US who are interested in the studying the evolution of behaviour.
"Flamingos captured my attention for a variety of reasons," says Anderson.
"Scientifically speaking, their highly gregarious nature makes them an ideal species for investigating social influences on behaviour."
"Aesthetically speaking, they are large, beautiful, and iconic."
"Perhaps most importantly, I was very surprised to discover how little systematic, hypothesis-driven empirical research had been conducted on flamingos."