Conventional types of genetic analysis may not be as accurate as believed, according to researchers writing in Trends in Genetics.

Their analysis of penguins that died 44,000 years ago in Antarctica have provided extraordinary frozen DNA samples that they say challenges the accuracy of traditional genetic aging measurements, and suggest those approaches have been routinely underestimating the age of many specimens by 200 to 600 percent.  So a biological specimen determined by traditional DNA testing to be 100,000 years old may actually be 200,000 to 600,000 years old.

They say their findings raise doubts about the accuracy of many evolutionary rates based on conventional types of genetic analysis.

Newtonian mechanics has marked the beginning of a new era for physics. Indeed the newtonian formulation of the gravitational force has allowed to prove the heliocentric theory developped by Copernicus and defended by Galileo. It is a very interesting story that deserve a full post (maybe one day, if I have enough time...).

The burgeoning demographics of aging, which is transforming cites and suburbia alike, recently prompted me to attend the UCLA Conference on Technology and Aging, held at the lovely Skirball Center, cultural hub of LA’s older Jewish community. The following are unedited excerpts from my diary:

9:00 am: Arrive, following hour on freeway. Write down number of parking lot space on back of hand. Will be accused of being 13-year-old girl.

I have to delay the Sunday Science Book Club and my discussion of Voyage of the Beagle until next week. In the mean time, I'm initiating the first Post-Apocalyptic Sci-Fi Corner. Over the next few months, I'll share my experiences as I work through my list of post-apocalyptic sci-fi, one of my favorite fiction genres.

Post-Apocalyptic Sci-Fi Corner
Far North, by Marcel Theroux
Farrar, Straus, Giroux, 2009

While it's generally accepted that melting polar ice due to global warming is bad, scientists from the British Antarctic Survey are reporting this week that the loss of ice in the world's southernmost region could actually be slightly slowing the pace of climate change.

Large blooms of tiny marine plants called phytoplankton are flourishing in areas of open water left exposed by the recent and rapid melting of ice shelves and glaciers around the Antarctic Peninsula. This remarkable colonization is having a beneficial impact on climate change. As the blooms die back phytoplankton sinks to the sea-bed where it can store carbon for thousands or millions of years.

With the so called obesity epidemic in full swing, many people have turned to low-carb, high-fat diets as an alternative way to lose weight in recent years. While these diets can help people lose weight, some scientists say that they do very little to improve  mood and cognition.

A study published today in the Archives of Internal Medicine followed two groups of dieters for one year and found that a low-calorie, low-fat diet appears to be more beneficial to dieters' mood than a low-carbohydrate plan with the same number of calories

Boston University Researchers have shown that intermittent access to fatty and sugary foods induces changes in the brain that are comparable to those observed in drug dependence. The findings, reported in the  Proceedings of the National Academy of Sciences, may help explain how abstinence from these foods contributes to relapse eating among dieters as well as related eating disorders.

The researchers used 155 rats to measure the neurobiological responses. The first group, the diet cycled subjects, repeatedly ate standard rat chow for five days, followed by a highly palatable, high-sugar, chocolate-flavored chow for two days.

The first human embryonic stem cell treatment approved by the FDA for human testing has been shown to restore limb function in rats with neck spinal cord injuries – a finding that could expand the clinical trial to include people with cervical damage.

Results of the cervical study currently appear online in the journal Stem Cells. UCI scientist Hans Keirstead hopes the data will prompt the FDA to authorize clinical testing of the treatment in people with both types of spinal cord damage. About 52 percent of spinal cord injuries are cervical and 48 percent thoracic.

Everybody has memories they'd like to forget forever. Now, thanks to research conducted by scientists at the Friedrich Miescher Institute for Biomedical Research, there might be a pill for that.

According to their study recently published in Science, it may soon be possible to control fear memories with extinction-based drug therapies.

The Researchers studied proteins in mice known as extracellular matrix chondroitin sulfate proteoglycans and discovered that they form 'neural nets' in the brain which protect against the erasure of fear memories. By giving the mice a drug called chondroitinase ABC, the researchers say they were able to degrade these perineuronal nets and render subsequently acquired fear memories susceptible to erasure.

In July 1999, Medicare began increasing coverage for people needing a simultaneous kidney/pancreas transplant in hopes of addressing racial and economic disparities that existed. But increased Medicare dollars have not translated into more access for African Americans or Hispanics, and researchers from Georgetown University claim they know why.

The team says that racial bias among physicians may prevent black and Hispanic patients from receiving necessary kidney/pancreas transplants at the same rate as similar patients in other racial groups. Their research is published in the November issue of the American Journal of Transplantation