Clinicians from the USC School of Dentistry have made the first epidemiological study of oral cancer in California and detailed a connection between the incidence of oral cancer and race and ethnicity.

Dr. Satish Kumar and Dr.Parish Sedghizadeh, clinical professors in the school’s Division of Diagnostic Sciences, went through 20 years of records from the California Cancer Registry (CCR)— the state’s cancer surveillance database — for the incidence rates of invasive squamous cell carcinoma, the most common form of oral cancer.

Up to two-thirds of oral cancers are caused by tobacco or alcohol use, according to the Oral Cancer Foundation.

When ancient retroviruses slipped bits of their DNA into the primate genome millions of years ago, they successfully preserved their own genetic legacy. Today an estimated 8 percent of the human genetic code consists of endogenous retroviruses (ERVs)--the DNA remnants from these so-called "selfish parasites."

Surprisingly, the infected hosts and their primate descendants also appear to have benefited from this genetic invasion, new evidence suggests. The ancient retroviruses--distant relatives of the human immunodeficiency virus (HIV)--helped a gene called p53 become an important "master gene regulator" in primates, according to a study published this week in the Proceedings of the National Academy of Sciences.

The first “State of the Carbon Cycle Report” for North America, released online this week by the U.S. Climate Change Science Program, finds the continent’s carbon budget increasingly overwhelmed by human-caused emissions.

North American sources release nearly 2 billion tons of carbon into the atmosphere each year, mostly as carbon dioxide. Carbon “sinks” such as growing forests may remove up to half this amount, but these current sinks may turn into new sources as climate changes.

“By burning fossil fuel and clearing forests human beings have significantly altered the global carbon cycle,” says Chris Field of the Carnegie Institution’s Department of Global Ecology, one of the report’s lead authors.

A comparison of illness and death rates for 13 vaccine-preventable diseases in the U.S., before and after use of the vaccine, indicates there have been significant decreases in the number of cases, hospitalizations and deaths for each of the diseases examined, according to a study in the Journal of the American Medical Assocation.

In the United States, vaccination programs have made a major contribution to the elimination of many vaccine-preventable diseases and significantly reduced the incidence of others.

“Vaccine-preventable diseases have societal and economic costs in addition to the morbidity and premature deaths resulting from these diseases—the costs include missed time from school and work, physician office visits, and hospitalizations,” the authors write.

Whereas most birds are sole proprietors of their nests, some tropical species “time share” together – a discovery that helps clear up a 150-year-old evolutionary mystery, says Queen’s University Biology professor Vicki Friesen.

The Queen’s-led international study confirms one of Charles Darwin’s more controversial theories – first put forward in 1859 and since disputed by many experts – that different species can arise, unhindered, in the same place. Others believe that a geographic barrier such as a mountain or a river is required to produce two separate species.

Although focused on how species change over time through natural selection, Darwin’s landmark book, The Origin of Species, also speculates that it is possible for different species to develop in the same place.

The CO2 emissions of 50,000 power plants worldwide, the globe’s most concentrated source of greenhouse gases, have been compiled into a massive new database, called CARMA — Carbon Monitoring for Action.

The on-line database, compiled by the Center for Global Development (CGD), an independent policy and research organization that focuses on how the actions of the rich world shape the lives of poor people in developing countries, lays out exactly where the CO2 emitters are and how much of the greenhouse gas they are casting into the atmosphere.

There is little substantive evidence that binge drinking while pregnant seriously harms the developing fetus, finds a study in the Journal of Epidemiology and Community Health.

Consistently heavy drinking throughout pregnancy has been associated with birth defects and subsequent neurological problems. But it is not known what impact binge drinking, in the absence of regular heavy drinking, might have. And this drinking pattern is becoming increasingly common, particularly among women, say the authors.

Their findings are based on a comprehensive review of published research on binge drinking and women who were either pregnant or trying to conceive.

In our first exciting episode of 'Who’s Smarter: Chimps, Baboons or Bacteria? The Power of Group IQ' ( Part I ) we showed how small-brained baboons can outsmart big-brained chimpanzees and how bacteria can out-innovate chimps, baboons, and you and me. We also visited an evolutionary mystery in the world of a bacterial buddy that's with you every day, the E. coli found in your gut.

In a lab dish, E. coli can do something neo-Darwinian theory says just can not be.

Agroforestry is the integration of trees and shrubs in agricultural areas, like farmland, to help protect the soil and in some cases to provide additional income.

Reduced soil erosion, biodiversity conservation and carbon sequestration are some of the major effects agroforestry systems have on the environment.

Yet many of the areas crucial to world ecology are in developing countries where it is a difficult sell to discourage maximum utilization of available land for crops.

A new study from the Karolinska Institutet states that consumers of Swedish moist snuff – a smokeless tobacco called 'snus' – run a higher risk of dying from cardiac arrest and stroke. Snus also increases the risk of high blood pressure, a known factor of cardiovascular disease.

The use of snus has increased markedly in Sweden in the past few decades, so much so that it now accounts for half of all tobacco consumption in the country. Over 20 per cent of men between the ages of 18 and 79 are daily users.