Electronic cigarettes fail to deliver nicotine to the consumer and be should be regulated and packaged in a manner consistent with the product's effect – even if that effect is a total failure to deliver nicotine as demonstrated, according to a study published in Tobacco Control.

Electronic cigarettes consist of a battery, heater and cartridge containing a solution of nicotine, propylene glycol and other chemicals and have been marketed to deliver nicotine without tobacco toxicants. Despite no published data concerning safety or efficacy, these products are sold in shopping malls and online. Further, "electronic cigarettes" currently are unregulated in the U.S., unlike other products intended to deliver nicotine to smokers such as lozenges, gum and patches.

Researchers from the University of California, San Diego have discovered the origin of strains of the human immunodeficiency virus (HIV) among men who have sex with men. The team says the results are important because knowing the mechanisms by which HIV uses human sex to spread is essential to stopping the HIV epidemic.

It is known that most HIV infections worldwide result from exposure to the HIV virus in semen, made up of seminal cells and the fluid around these calls, called seminal plasma. HIV virus particles contain RNA and exist in the plasma, while infected seminal cells contain HIV DNA.

Writing in the journal Radiocarbon, researchers report the development of a new calibration curve that could answer key questions about human evolution and climate change. The new calibration curve, which extends back 50,000 years, is a major landmark in radiocarbon dating-- the method used by archaeologists and geoscientists to establish the age of carbon-based materials.

The curve, called INTCAL09, not only extends radiocarbon calibration but also considerably improves earlier parts of the curve.

It takes Saturn almost thirty years to orbit the Sun, with the opportunity to image both of its poles occurring only twice in that period. 2009 brought a unique chance for Hubble to image Saturn with the rings edge-on and both poles in view. At the same time Saturn was approaching its equinox so both poles were equally illuminated by the Sun's rays.

A series of experiments on honey bees foraging for food has revealed that the bees warn their nest mates about dangers they encounter while feeding with a special signal that is akin to a 'stop sign' for bees.

The bees were attacked by nearby colonies while fighting for food at an experimental feeder and produced a specific signal to stop nest mates who were recruiting others for this dangerous location. Honey bees use a waggle dance to communicate the location of food and other resources. Attacked bees directed "stop" signals at nest mates waggle dancing for the dangerous location.

A new study in Clinical Pediatrics claims that the obesity 'tipping point', the point at which children begin their progression towards obesity in adulthood, begins at the age of two and sometimes as early as three months.  The authors warn that while many adults consider a chubby baby healthy, too many plump infants grow up to be obese teens, saddling them with Type-2 diabetes, elevated cholesterol and high blood pressure

A team of scientists from Princeton University and The Cancer Institute of New Jersey are attempting to unravel the secret lives of cancer cells that go dormant and self-cannibalize to survive periods of stress, a process called autophagy. The work may help produce new cancer therapies to stem changes that render cancer cells dangerous and resistant to treatment.

When administered in lethal levels, antibiotics trigger a fatal chain reaction within  bacteria that shreds the cell's DNA. But, when the level of antibiotic is less than lethal the same reaction causes DNA mutations that are not only survivable, but actually protect the bacteria from numerous antibiotics beyond the one it was exposed to, says a new study recently published in Molecular Cell. The findings underscore the potentially serious consequences to public health of administering antibiotics in low or incomplete doses.

An analysis of available research on the topic (three studies) suggests that eating choclate may reduce your risk of stroke. Chocolate is rich in antioxidants called flavonoids, which may have a protective effect against stroke, but more research is needed, concluded the analysis that will be presented at the American Academy of Neurology's 62nd Annual Meeting in Toronto April 10 to April 17, 2010.

 The first study found that 44,489 people who ate one serving of chocolate per week were 22 percent less likely to have a stroke than people who ate no chocolate. The second study found that 1,169 people who ate 50 grams of chocolate once a week were 46 percent less likely to die following a stroke than people who did not eat chocolate.

Data collected on speleothem encrustations, a type of mineral deposit, in coastal caves on the Mediterranean island of Mallorca indicate that sea level was about one meter above present-day levels around 81,000 years ago. The finding challenges other data that indicate sea level was as low as 30 meters below present-day levels. Theories about the rates of ice accumulation and melting during the Quaternary Period may need to be revised as a result of the findings, which appear this week in Science.

The sea level high stand of 81,000 years ago was preceded by rapid ice melting, on the order of 20 meters of sea level change per thousand years and the sea level drop following the high water mark, accompanied by ice formation, was equally rapid.