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Blood test to detect thoughts of committing suicide? Birds observe speed limit on roads Prof Yash
Pal  If the Earth revolves around the Sun due to its gravitational
Pull, what causes it to spin around its own axis? Why does the boiling point of liquid remain the same?
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Blood test to detect thoughts of committing suicide?
US research has raised the controversial prospect of using a blood test to detect thoughts of committing suicide. For the first time, suicide risk has been linked to biomarkers in the blood by researchers looking into predictors. Scientists found increased amounts of specific proteins in the blood stream of people who were contemplating suicide. The study, conducted by researchers at Indiana University, found that an enzyme called SAT1 was linked to suicidal tendencies. The study involved taking samples from participants over an extended period of time, whilst interviewing them at three to six month intervals. At least 75 males with conditions such as bipolar were used as participants, as they are at a higher risk of committing suicide than others. Researchers then tested the samples to look for differences in protein activity. The increased presence of this specific blood marker was apparent in a subgroup of nine patients who displayed a sudden dramatic shift to powerful suicidal thoughts. A similar pattern was seen in blood samples taken from nine suicide victims who had succeeded in taking their own lives. Raised levels of the biomarkers correlated with admissions to hospital after suicide attempts. The link was stronger for bipolar disorder than for schizophrenia. Researchers in the US now argue their results are “proof of principle” for a suicide test. Study leader Dr Alexander Niculescu, from Indiana University, said: “Suicide is a big problem in psychiatry. It’s a big problem in the civilian realm, it’s a big problem in the military realm and there are no objective markers. “There are people who will not reveal they are having suicidal thoughts when you ask them, who then commit it and there’s nothing you can do about it. We need better ways to identify, intearvene and prevent these tragic cases. “These seem to be good markers for suicidal behaviour in males who have bipolar mood disorders or males in the general population who commit impulsive violent suicide. In the future we want to study and assemble clinical and socio-demographic risk factors, along with our blood tests, to increase our ability to predict risk.” However, because the number of participants used in the study was relatively low at 75 and all male, Dr Niculescu said he plans to conduct further research focusing on more deliberate and planned suicides with a bigger and more varied sample. “There could be gender differences,” he said. “We would also like to conduct more extensive, normative studies in the population at large.” “Over a million people each year worldwide die from suicide and this is a preventable tragedy,” he added. In their paper, the scientists point to a link between SAT1 and polyamine, a chemical involved in apoptosis, or “cell suicide” — the programmed self-destruction of damaged or harmful cells. They wrote: “It could be that... mechanisms related to cellular survival have been recruited by evolution for higher mental functions, such as feelings, thoughts, actions and behaviours, leading to suicidality. “In that sense, suicidality could be viewed as a whole-organism apoptosis.” Lithium, a treatment for bipolar disorder shown to prevent suicide, suppresses apoptosis at the cellular level, they pointed out. But British scientists warn the research should be treated with caution. Professor Keith Hawton, director of the Centre for Suicide Research at Oxford University, said: “There is a big difference between finding differences between groups (as in this study) compared with risk in actual individuals, the latter being the real test of predictors. “I would say that the findings are of interest and may point the way to some future research based on large samples, but no more than that.” Professor Matthew Hotopf, from the Institute of Psychiatry at King’s College London, stressed the need to have the results replicated by other studies. He added: “It’s one thing to find a biomarker which might be associated at a statistical level with suicide/ suicidal behaviour. It’s quite another to use it to make any kind of prediction which has clinical utility. “These findings may attract media attention, but they are very much preliminary and my money would be on failed replication and even if replication was successful, lack of predictive power to be a useful clinical tool.” — The Independent
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Birds observe speed limit on roads BIRDS observe speed limits on the roads even if motorists choose to ignore them, a study has found. On roads with higher speed limits, birds are quicker to take to the air to avoid on-coming traffic, but where limits are lower, they wait longer. The behaviour is related to speed restrictions and not the result of birds assessing the speed of approaching vehicles, researchers found. Scientists admitted breaking speed limits to carry out the study in western France. Motoring through the French countryside in a white Peugeot hatchback, they recorded the activity of birds standing on or at the edges of roads with speed limits of 20, 50, 90 and 110 kph. The car was driven at, under or over the speed limit and a timer used to calculate “flight initiation distance” (FID) — the closest distance the car came before the birds flew out of danger. A total of 134 FIDs were measured for 21 species. The researchers, led by Pierre Legagneux, from Laval University in Canada, wrote in the Royal Society journal Biology Letters: “Birds had significantly higher FID on road sections with higher speed limits. “By contrast, car speed had no significant effect on FID, both when considering absolute car speed or the difference between car speed and speed limit.” Reacting to speed limits on roads is the result of birds adapting to what they consider a “habitat characteristic”, the scientists suggest. “As road traffic directly causes mortality in birds, we expect birds to respond to road traffic in a similar way as they would respond to predation,” said the researchers. “As road mortality probably increases with speed limits we would expect individuals to adjust their anti-predator behaviour to vehicle speed and/or to the speed limit. Species with longer FID are known to have smaller risk of getting killed by cars, suggesting that adjusting FID might be an adaptive way to respond to road traffic.” They added: “Our results show that birds change their FID according to speed limit rather than car speed. This strongly suggests that birds are able to associate road sections withspeed limits as a way to assess collision risk.” Three species, the carrion crow Corvus corone, the house sparrow Passer domesticus, and the blackbird Turdus merula, accounted for more than half the study data. FID increased with body mass, with smaller, more agile species waiting longer before taking flight. Birds standing in the middle of the road were more cautious than those at the edges and had greater
FIDs.
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THIS UNIVERSE Planets are not finished objects sitting around to be picked up by a star and taken unto the fold of a family. Planets are probably big blobs of dust and other material around a forming star. These blobs are also going through the effort of getting together in slow chaotic collisions and collection. Random falling towards their centres of mass, it is normal for them to acquire angular momenta. Conservation of angular momentum leads to varied levels of rotation and perhaps that is what we call a spin of a planet, which ultimately gives the planet its days and nights and, often its magnetic field. Sometime this once blob of material can form into a planet like Earth. To summarise for an answer to your question, the rotation of planets is connected with their chaotic formation. Zero angular momentum can occur, but it will be very improbable. Why does the boiling point of liquid remain the same? We could think of the boiling point of liquid as the temperature at which the kinetic energy of most of the molecules becomes greater than the attraction of the molecules with each other. That is the temperature beyond which molecules cannot stay confined within the liquid state. The boiling point depends on the strength of the inter-molecular forces of the liquid concerned; it is one of its intrinsic properties. Readers can e-mail questions to Prof Yash Pal at palyash.pal@gmail.com
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CAPE CANAVERAL, Florida: NASA’s long-lived Voyager probe crossed into interstellar space last year, becoming the first man-made object to leave the solar system, new research shows. Scientists have been waiting for Voyager to detect a magnetic field that flows in a different direction than the solar system's magnetic field. But the new research shows that scenario is not accurate. Sliced and diced, digitally: Autopsy as a service SINGAPORE: Malaysian entrepreneur Matt Chandran wants to revive the moribund post-mortem by replacing the scalpel with a scanner and the autopsy slab with a touchscreen computer. He believes his so-called digital autopsy could largely displace the centuries-old traditional knife-bound one, speeding up investigations, reducing the stress on grieving families and placating religious sensibilities. New mammal species discovered WASHINGTON: The long-tailed, orange-furred, big-eyed olinguito — said to resemble a cross between a house cat and a teddy bear — is the newest mammal and the first carnivore discovered in the Americas in 35 years, the Smithsonian Institution announced recently. Native to the high, misty cloud forests of Colombia and Ecuador, the olinguito is the smallest member of the raccoon family, according to Kristofer Helgen, a Smithsonian scientist who recognised it as a distinct species 10 years ago. — Reuters
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