Estimates can be funny things because usually they're brought up by people with agendas rather than people interested in objective analysis.  Some estimates in competitive sports put athletic doping usage at 95%, for example, which sounds ridiculously high unless your slippery slope meter works overtime.

What about academia?   The non-medical use of methylphenidate and amphetamine is as high as 25% on some US college campuses, particularly in colleges with more competitive admission criteria, says Vince Cakic of the Department of Psychology at the University of Sydney.  And the use of smart drugs - "nootropics" - to boost academic performance is increasing.

A research team led by Dr Howard Falcon-Lang from Royal Holloway, University of London, analyzed spectacular discoveries of 300-million-year-old rainforests in Illinois coal mines and came to a conclusion that won't surprise most - Mother Nature is resilient.

Climate change wreaked havoc on these early rainforests but they quickly bounced back, they write in Geology.  The ancient rainforests date from the Carboniferous period, 300 million years ago, when most of the world's coal resources were formed.

Researchers writing in BMC Cancer say that post-menopausal women who engage in moderate or vigorous exercise have reduced risk of breast cancer.

Over 110,000 post menopausal women were asked to rate their level of physical activity at ages 15-18, 19-29, 35-39, and in the past 10 years. It was found, over 6.6 years of follow up, that women who engaged in more than 7 hours per week of moderate-to-vigorous exercise for the last ten years were 16% less likely to develop breast cancer than those who were inactive. However, no link was observed between breast cancer risk and physical activity in women who were active at a younger age.

There's drama in two galaxies in the Virgo Cluster, NGC 4522 and NGC 4402.    An extremely hot X-ray emitting gas known as the intra-cluster medium lurks between galaxies within clusters and, as galaxies move through this intra-cluster medium, strong winds rip through galaxies distorting their shape and even halting star formation - a process known as "ram pressure stripping".

Result: Peculiar looking galaxies.

Ram pressure is the drag force that results when something moves through a fluid — much like the wind you feel in your face when bicycling, even on a still day — and occurs in this context as galaxies orbiting about the centre of the cluster move through the intra-cluster medium, which then sweeps out gas from within the galaxies.

Women who considered themselves sexually satisfied had a higher overall psychological well-being score and scores for "positive well-being" and "vitality," compared with sexually dissatisfied women in a study of 295 women sexually active more than twice a month. The study was published today in The Journal of Sexual Medicine, also uncovered a positive association between age and well-being, but a negative association for general health.  The results applied to pre- and post-menopausal women.

In scoliosis treatment for babies, doctors often try bracing first and if that fails, they escalate to surgery; placing metal rods in their backs with spinal fusion.

These children face the risk of complications from the surgery and their backs and chests may be stiff for life.    New research from the University of Rochester Medical Center (URMC) may lead doctors to choose to optimize an old technology – casting – instead of using high-tech implantable devices. Casting has fewer, and less serious potential complications and it requires no surgery. In fact, with the right training and equipment, the specialized series of casts can be done as outpatient procedures.