We present live coverage from NPR of President Obama's news conference announcing his nomination of Massachusetts Senator John Kerry for secretary of state. First, journalist Mark Sandalow joins us from Washington to discuss the pick.

The entire nation has been shaken by the brutal killings of 20 children and six adults from Sandy Hook Elementary School in Newtown, Connecticut. Less discussed has been the pervasive gun violence in some urban communities. Last year in Oakland, nearly 150 kids under the age of 18 were victims of shootings. Six were killed. We discuss the effects of gun violence on a community. How does it impact children and their families, and what can be done to help?

On Monday, futurist and visionary inventor Ray Kurzweil joined Google as its new director of engineering, to work on projects related to machine learning and language processing. We'll talk to Kurzweil about his new position and his latest book, "How to Create a Mind: The Secret of Human Thought Revealed."

This Friday, December 21, is when the Mayan calendar appears to wrap up its most recent long-count cycle of 5,125 years. It's also a day some believe will bring the end of the world. They predict a rogue planet will collide with Earth, or that other planets will align and cause a giant blackout. But NASA experts say there's nothing on the horizon, and that the doomsday theory is a misreading of the Mayan calendar. Still others believe the world will undergo a spiritual, not physical, transformation. Why is the idea of an apocalypse so popular?

From Sean Penn in "Fast Times at Ridgemont High" to Alicia Silverstone in "Clueless," Hollywood loves to celebrate the California accent. But besides the Valley girls and surfer dudes, do Californians really have an accent? One Stanford team is testing that idea and studying dialects across the state. What are they finding? Do certain words or tonalities make us classic Californians? Do you think you have an accent?

On Tuesday, state regulators released draft rules for hydraulic fracturing, a controversial drilling technique known as fracking. Energy companies hope the new rules will give them the green light to tap into previously inaccessible oil reserves. But environmental groups say fracking contaminates groundwater, pollutes the air and even induces earthquakes. We'll discuss the benefits and risks of fracking, as well as the proposed regulations.

The history of Afghanistan is often understood in terms of invasions. The area has been occupied by the likes of Alexander the Great and Genghis Khan, and, more recently, the Soviet Union and the U.S.-led NATO coalition. But the country has its own compelling story independent of the interventions, writes San Francisco-based author Tamim Ansary. The Kabul native joins us to discuss his new book, "Games Without Rules: The Often Interrupted History of Afghanistan."

As the country grapples for answers in the aftermath of the Newtown massacre, some are pointing to violence in the media as a potential culprit. Do violent movies, TV shows and video games promote aggressive behavior in youth? We look at the latest research.

On Sunday, Connecticut Senator Joe Lieberman called for "a national commission on violence" in the wake of the Newtown massacre. The commission would look at the country's mental health system, as well as gun laws and other factors. Could better access to mental health services help prevent future tragedies? We discuss mental illness, public policy and the psychology of mass murderers.

In a speech at a memorial in Newtown, Connecticut on Sunday, President Obama vowed to use the power of his office to prevent future mass killings. But he stopped short of mentioning any specific proposals. Gun control advocates, including California Senator Dianne Feinstein -- who has said she will push for a new assault weapons ban -- are calling on the president to act. But supporters of gun rights say that new laws are not the answer, pointing out that Connecticut already had tough firearm regulations.