the-BA : Science News Digest

Blue Fruit (Image copyright: iStockPhoto.com)

In the news this week: a virtual dinosaur race, noise pollution increases the risk of heart attacks and Google looks to the Sky. Plus, the evolutionary origins of the pink/ blue gender divide...

In recent years it has been fashionable among the health conscious to consume vast quantities of so called super-foods. The health benefits of foods such as blueberries, oily fish, brazil nuts and the exotic acai berry have been much touted but often without any hard evidence. The case for the blueberry is looking much stronger this week after a team of US researchers announced that it contains a pigment that may slow the growth of cancer cells, reported the Guardian.

The chemicals involved are known as anthocyanins and are the group of antioxidants that give red, purple and blue fruits their vibrant pigments. The scientists extracted the compound from a range of fruit and added it to a flask containing colon cancer cells. They found that those fruits with the highest proportion of the compound, such as purple corn, could actually kill the cancerous cells, with no damage to the healthy ones. Even foods that were less highly coloured like radishes slowed the growth of the cells by 50 to 80 per cent. The team also fed rats bred to develop colon cancer a diet containing extracts from bilberries and chokeberries, substances usually found in jams and fruit drinks. They found that the rat’s colon tumours decreased by 60 to 70 per cent compared with those on a normal diet.

Anthocyanins are not easily absorbed into the bloodstream and are not picked up by local tissues until they reach the gastrointestinal tract. The scientists believe that it is this slow absorption that makes them effective against colon cancer. They are looking into ways of altering the structure to make them even more potent. Henry Scawcroft from Cancer Research UK said: ‘In the future, it could lead to the development of drugs that help prevent bowel cancer in people at high risk.’

Is their anything that the long arm of Google cannot reach? Not satisfied with providing the public the means to check out their neighbour’s garden or view the Grand Canyon at a click of the mouse, the mammoth search engine has added another strand to the Google package and turned its attention to the heavens. In a project that brings together Nasa, the United Kingdom Astronomy Technology Centre and the Anglo-Australian Observatory, Sky in Google Earth will bring together images from a number of telescopes that are already available on the web in an accessible, user friendly form enabling everyone access to ‘the wonders of our Universe’.
The facility promises to show users 100 million stars and 200 million galaxies, reported the Times. They can take a virtual tour through the Ursa Major galaxy, zoom in on particular cosmic features and watch a star’s evolution from its birth to the eventual catastrophic supernova. The programme has been designed to show the sky from any point on the Earth’s surface on a clear night. It is aimed at both amateurs and professionals and allows users to submit their own content.

Carol Christian, of the Space Telescope Science Institute in the United States, who was part of the team that created the site said: ‘Never before has a road-map of the entire sky been made so readily available. Sky in Google Earth will foster and initiate new understanding of the Universe by bringing it to everyone’s home computer.’

It can be frustrating being an epidemiologist; trying to understand how disease spreads and how a population will react when all you have to rely on is mathematical based models or evidence from historical studies. The deliberate release of an infectious disease is, of course, out of the question. So how do you get data on actual human behaviour without provoking a pandemic? Computer programmers at Blizzard Entertainment may have unintentionally bridged the gap between real life and computer models, says a report in the medical journal, the Lancet.

In September 2005 the programmers of the popular World of Warcraft game released a virtual disease, known as ‘corrupted blood’ into their virtual world inhabited by 6.5 million players across the globe. The players control their characters or avatars and interact with each other in role-play scenarios. The disease was initially designed to challenge only the strongest characters in an isolated area but it soon spread across the virtual world ‘Black Death’ style because the programmers had not realised that their malicious code could also infect pets and non-player characters.

In the business, World of Warcraft is known as a ‘massive multiplayer online role-playing game’ with players spending many hours transported to this realm of monsters and epic adventures, thus often becoming emotionally attached to their avatar. This means that their reaction to the virtual disease was a good representation of how people might respond in real life. Some players acted altruistically, putting themselves at risk in order to save others, some tried to avoid infection by abandoning cities, and some who were already ill, tried to infect others.

Even though people may have reacted more extremely than they would in real life, scientists say this could be corrected for and that this virtual plague may offer a valuable insight into human behaviour during times of crisis. Researcher Professor Nina Fefferman, one of the authors of the report from Tufts University School of Medicine, explained to the Times: ‘If, God forbid, a disease broke out in London, you could see what would happen if people were told immediately of the risk. Would there be panic and chaos, or would it allow them to psychologically accept the danger and act accordingly? …They are also things we just don’t know, so [virtual games] could be of great value in helping us understand what their true emotional responses would be.

A dripping tap, a rowdy party, the sound of planes taking off; these are all sources of noise pollution that will have irritated most of us at some point. But are these disturbances any more serious than an inevitable annoyance, unavoidable in our frenetic lives? A report published by the World Health Organisation (WHO) this week concludes that we need to consider noise as a serious threat to human health with thousands of people dying prematurely as a result of prolonged exposure.

101,000 people died of coronary heart disease last year in the UK and as many as 3030 of those deaths could be linked to chronic noise exposure, reported the Guardian.
There is mounting pressure on European governments to take the threat seriously with a new law coming into effect by the end of the year that states that all cities of over 250,000 inhabitants must produce digitised sound maps that highlight noise pollution hotspots. Measures such as using low-noise tyres and road surfaces, erecting anti-noise barriers and rerouting traffic to avoid schools and hospitals could be implented in these areas.

Scientists think that it is the stress response that noise provokes that is detrimental to our health. Even while we are sleeping, our body is absorbing sounds, alert for any sign that we might need to wake up and escape a disturbance. If we are in a noisy environment, the stress hormones such as adrenaline and cortisol are constantly circulating in our bloodstream and will eventually take their toll on our health, affecting the immune system, causing high blood pressure and in extreme cases, heart failure and strokes.

The researchers from the WHO's Noise Environmental Burden on Disease group used methods similar to those used to measure the affect of cigarette smoke and air pollution on health. They compared the incidence of death and disease in areas of high noise pollution with those in quieter neighbourhoods. They also studied people suffering from coronary heart disease and tried to determine whether exposure to noise may have contributed to them developing the disease. This data was then superimposed on the sound maps and calculations made to estimate how many people may die or develop disease as a result of the noise.

One in ten people report having an out-of-body experience (OBE) at one time in their lives. The phenomenon has long fascinated philosophers and scientists alike as it has implications for how we perceive our conscious ‘self’. This week scientists reported that they were able to recreate the out-of-body experience in a lab and have studied the neurology behind these events.

The teams asked volunteers to wear video display goggles and using camera techniques showed them a 3D image of their own back, standing a few metres in front of themselves. A team member would then stroke their real body with a plastic rod. This image was relayed to the goggles either simultaneously or with a time delay. The volunteers reported sensing the contact as though the plastic rod on the virtual body had provoked the sensation. In other words, they felt that the virtual body was their own. The feeling remained even when their virtual body was replaced by that of a mannequin.

When the volunteers had removed the goggles, they were moved back a few places and then asked to return to their original position. The volunteers seemed disorientated and always over-estimated the distance, as though they were going to stand where their hologram self had been. They also showed a stressed physiological response when they saw their virtual self under threat.

Dr Henrik Ehrsson from UCL said: ‘This experiment suggests that the first-person visual perspective is critically important for the in-body experience. In other words, we feel that our self is located where the eyes are.’ They think some OBEs can be explained by a disconnection between the area of the brain that receives visual information and that receiving touch information from our sense organs. This insight could help computer programmers reach the next level of virtuality in computer games or enable surgeons to perform remote surgery by convincing the brain the body is somewhere else, reported BBC News.

Since Jurassic Park saw Tyranosaurus-rex struggle to catch a speeding Jeep, numerous theories have surfaced on just how agile this giant hunter was, with some even questioning its ability to run at all. New research published this week suggests that T-rex could have hunted today’s fastest sportspeople, managing an impressive 18mph. The speediest specimen was the Compsognathus, a small two-legged dinosaur that could reach 40mph, 5mph faster than the fastest modern equivalent, the ostrich.

Co-author David Manning told the Daily Telegraph: ‘Our research, which used the minimum leg muscle mass T-Rex required for movement, suggests that while not incredibly fast, this carnivore was certainly capable of running and would have little difficulty in chasing down footballer David Beckham, for instance.’
A team of biomechanics and palaeontologists from the University of Manchester developed a computer programme that simulates the most efficient posture and gait for a range of bipedal dinosaurs and allows the calculation of their top running speed. They fed a powerful supercomputer information on various dinosaurs’ skeleton and muscle structures and left it to run through the all the possible ways the beasts could have moved. It took the computer a week to learn how to run like each dinosaur.

The results are described as the most accurate ever. Previous studies have relied on the assumption that dinosaurs could be modelled as scaled up versions of living animals but even inflating a chicken to six tonnes will not make it an accurate representation of a dinosaur.

Other news in brief:

The oldest diamonds found in the Earth’s crust hint that plate techtonics may have begun much earlier than previously thought. The tiny diamonds found in western Australia are thought to be 4.25 billion years old. Their structure suggests that the planet had cooled sufficiently by then for the crust to have formed on the Earth’s surface.

‘We have compared these diamonds with known diamonds and so far it seems like the most similar diamonds are ultra-high pressure diamonds which form in a subduction process,’ explained Martina Menneken from Westfalische-Wilhelms University, Germany. ‘Today these form in plate tectonics surroundings. The implication is: did we have plate tectonics at this early stage of the Earth? I still think this is controversial; we cannot prove it and we need to do further research,’ reported BBC News.

Mathematics has proved what wine sommeliers have known all along – it is more efficient to open a bottle of wine using a combination of twisting and pulling the cork than just pulling alone. Sixteen pages of mechanics and strain analyses were required to reach the conclusion, in which the cork was modelled as ‘an incompressible rubber-like material’. The work has implications for which type of corkscrew is best to impress the wine connoisseur at your next dinner party. Read more at the Daily Telegraph.

And finally…

Rather than just another stereotype, convenient for greetings card manufacturers and baby clothes designers, it seems that the saying ‘pink for girls, blue for boys’ does have some evolutionary basis.

Neuroscientists from the University of Newcastle showed 208 men and women aged 20 to 26 a series of pairs of coloured rectangles and asked them to pick out their favourite as fast as possible. The results show that overall both genders prefer blue but women also show a preference towards the red end of the spectrum, meaning that on average, females prefer pink or lilac hues, reported the Independent.

A significant minority of the volunteers were Chinese. The women from this group also showed the same preference, suggesting that colour choice has genetic basis rather than being a product of social conditioning.

As with most hardwired human traits, it can be explained by going back to our evolutionary roots in Africa. Dr Anya Hurlbert who led the study said: ‘Evolution may have driven females to prefer reddish colours - reddish fruits, healthy, reddish faces.’ She explained the universal taste for blue by saying: ‘Going back to our 'savannah' days, we would have a natural preference for a blue sky, because it signalled good weather.’