NASA's Mars Reconnaissance Orbiter has observed a new category of minerals spread across large regions of Mars. This discovery suggests that liquid water remained on the planet's surface a billion years later than scientists believed, and it played an important role in shaping the planet's surface and possibly hosting life.
Researchers examining data from the orbiter's Compact Reconnaissance Imaging Spectrometer for Mars have found evidence of hydrated silica, commonly known as opal. The hydrated, or water-containing, mineral deposits are telltale signs of where and when water was present on ancient Mars.
Last winter, the thickness of sea ice in large parts of the Arctic fell by nearly half a metre (19 per cent) compared with the average thickness of the previous five winters. This followed the dramatic 2007 summer low when Arctic ice extent dropped to its lowest level since records began.
Up until last winter, the thickness of Arctic sea ice showed a slow downward trend during the previous five winters, but after the summer 2007 record low extent, the thickness of the ice also nose-dived. What is concerning is that sea ice is not just receding but it is also thinning.
Children and adolescents who abuse alcohol or are sexually active are more likely to take methamphetamines (MA), also known as ‘meth’ or ‘speed’. Research published today in the open access journal BMC Pediatrics reveals the risk factors associated with MA use, in both low-risk children (those who don’t take drugs) and high-risk children (those who have taken other drugs or who have ever attended juvenile detention centres).
Applying electrical stimulation to the scalp and the underlying motor regions of the brain could make you more skilled at delicate tasks. Research published today in the open access journal BMC Neuroscience shows that a non-invasive brain-stimulation technique, transcranial direct current stimulation (tDCS), is able to improve the use of a person’s non-dominant hand.
Did the Bible's King David and his son Solomon control the copper industry in present-day southern Jordan? The possibility is raised once again by research reported in the Proceedings of the National Academy of Sciences.
Off-label prescription of a drug is generally legal, but promotion of off-label uses by a drug manufacturer is illegal. In an article in this week's PLoS Medicine, two physician researchers describe the techniques that they say drug companies use to covertly promote off-label use, even when such promotion is illegal.
Adriane Fugh-Berman (Georgetown University Medical Center) and Douglas Melnick (a preventive medicine physician working in North Hollywood, California) argue that while off-label drug use is "sometimes unavoidable" and sometimes "demonstrably beneficial," it has also been linked with serious side effects. Off-label drug use, they say, "should be undertaken with care and caution due to the uncontrolled experiment to which a patient is being subjected."