Natural gas is burned off next to an oil well being drilled at a site near Tioga, N.D., in August. U.S. oil production started increasing a few years ago and is predicted to continue to rise, reducing the country's dependence on oil imports.
With New York's legalization of same-sex marriage effectively doubling the number of Americans living in states where gays can marry, gay advocates like to say 2011 was a big year.
It's hard to imagine another doubling this year, but proponents are still hoping to build on last year's success. Same-sex marriage is currently legal in six states plus Washington, D.C., and it may come up for a vote in six more. All the while, legal challenges are pushing the issue closer to getting an opinion from the U.S. Supreme Court.
The more exposure children have to chemicals called perfluorinated compounds, the less likely they are to have a good immune response to vaccinations, a study just published in JAMA, the Journal of the American Medical Association shows.
The finding suggests, but doesn't prove, that these chemicals can affect the immune system enough to make some children more vulnerable to infectious diseases.