Discovered: Researchers investigate service members' sleep habits; brain-imaging for zebrafish; why pigeons get lost in the "Bermuda Triangle"; cancer death rates are down.
Sleep deprivation in the U.S. military. Readers of last year's best-selling Navy SEAL memoir No Easy Day got some insight into the sleeping habits of soldiers stationed abroad. The book made many references to Ambien, the sleep-aid that SEAL Team 6 took whenever they had time for some precious shut-eye. Now, thanks to a new study conducted at Madigan Army Medical Center and published in Sleep, we have hard numbers on the military's sleep deprivation problem. By reviewing charts from all the Center's admissions for sleep-related complaints, researchers were able to determine that two-thirds of soldiers with sleep problems get less than six hours of sleep per night. Forty-two percent got less than five. "It's really the first study to take a good epidemiological look at sleep in military personnel," comments University of Texas Health Science Center psychologist Alan Peterson. [Science News]
Look at this video of a zebrafish's brain. Have you ever wondered what the thoughts of a zebrafish look like? Probably not, unless you're a neuroscientist, in which case you know that studying this species can reveal much about how neural pathways work. Now, scientists have developed a new method of using green fluorescent proteins (GFPs) to reveal real-time activation of zebrafish neurons. Koichi Kawakami of Japan's National Institute of Genetics and his colleagues have demonstrated the usefulness of GFPs in young zebrafish, which remain transparent before maturing into adults. "The sensitivity resolution of this new green fluorescent protein is amazing," comments Martha Constantine-Paton of MIT. Take a look at the method in action below. [New Scientist]
Why homing pigeons get lost in this region of New York state. Homing pigeons are famous for being able to find their way home from far-flung place they've never visited before. But there's one spot in upstate New York where homing pigeons lose all sense of direction, and for years scientists struggled to understand why the birds' sharp navigation skills crumbled in this "Bermuda Triangle" area. But now, U.S. Geological Survey researchers have may cracked the mystery. Jonathan Hagstrum and his colleagues theorize that homing pigeons use low frequency sounds to orient themselves. They also found that the specific geological features of this site prevent them from hearing such frequencies. "The temperature structure and the wind structure of the atmosphere were such in upstate New York that the sound was bent up and over Jersey Hill," says Hagstrum. [BBC News]
Cancer death rates are declining. In the last 20 years, death rates from cancer have gone down by about 20 percent. CA: A Cancer Journal for Clinicians has issued its annual cancer mortality study, finding that while prostate and breast cancer are more common than ever before, cancer on the whole is getting more manageable due to early detection and new advances in treatment. John R. Seffrin, CEO of the American Cancer Society says, "We must also recognize that not all demographic groups have benefitted equally from these gains, particularly those diagnosed with colorectal or breast cancer, where earlier detection and better treatments are credited for the improving trends." Even though cancer death rates are falling, this report doesn't mean that rates of cancer development are declining, and it doesn't mean that the sheer number of people dying from cancer has gone down. [io9]