A. New Insight into the Human Circadian Rhythm

Narrator: This is Science Today. Whether you're a morning person or a night owl, we all have our own internal body clock, or circadian rhythm. This 24-hour cycle regulates a variety of biological processes, including sleep. Now, a University of California, San Francisco study offers new insight into this cycle. Ying-hui Fu led a study that identified a gene and mutation that causes a rare sleep behavior called Familial Advanced Sleep Phase Syndrome.

Fu: The main problem they have is they like to go to bed really early, like 4PM, 6PM and they like to get up very early, like 2AM, 4AM, 5AM.

Narrator: While this syndrome is rare, Fu says their study reveals that sleep behavior is genetically determined and the effects of the human circadian rhythm are far-reaching.

Fu: If you think of the circadian rhythm as a center, you can connect sleep, connect to depression, connect to learning and memory and then come back to migraine headache and then it connects to asthma, so it's very broad.

Narrator: For Science Today, I'm Larissa Branin.

B. Engineers Developing Assistive Technologies for the Blind

Narrator: This is Science Today. Engineers at the University of California, Santa Cruz are developing high-tech, assistive technologies for the blind. Roberto Manduchi, an assistant professor of computer engineering, developed the ‘virtual white cane – one of several prototype tools.

Manduchi: The virtual white cane is a device that eventually in its ultimate form will have the size of a flashlight that you can hold in your hand and point around a scene and the system will read distances. The idea is to try to have the same features that the real white cane has without having the hassle of a physical thing that bumps into people and objects.

Narrator: The technology is based on advances in computer vision that have emerged from research in robotics.

Manduchi: Technically, the way it works is with laser pointer, which is coupled with the little camera and a computer, which eventually can be manipulated and embedded and through a process called active triangulation, the system can read these distances in real time.

Narrator: For Science Today, I'm Larissa Branin.

C. When it Comes to Cholesterol, It's All in the Genes

Narrator: This is Science Today. Why is it that some people can eat what they want, not exercise and yet still maintain good cholesterol levels? According to a study led by the Lawrence Berkeley National Laboratory, it's all in the genes. Paul Williams, a researcher in the Lab's Life Sciences Division, says they studied 28 pairs of identical twins – one twin was a marathon runner, the other was much less active.

Williams: We were interested in finding out how identical twins would respond to high fat and low fat diets. This is in part motivated because some initial observation of ours suggested that the exercisers might have some protection from eating high fat diets.

Narrator: But their study found this was not the case – if one twin ate a high fat diet without increasing his bad, or LDL cholesterol, then so could his twin.

Williams: I think this starts to suggest that a great deal of the regulation of the bad cholesterol is through genes. We tend to tell everybody to follow a certain diet and there's a pragmatic part about it, but then people have to realize that there's a lot affecting how successful it's going to be in lowering their cholesterol.

Narrator: For Science Today, I'm Larissa Branin.

D. Growing Up in the Same Family Doesn't Mean the Same Experience

Narrator: This is Science Today. The emotional connection between sisters is very important, but it's a relationship that hasn't been explored in a serious way. That is until sociologist Marcia Millman of the University of California, Santa Cruz, interviewed nearly 100 women of diverse backgrounds from around the nation. Millman says the study was a reminder that even though sisters grew up in the same family, it didn't mean they had the same family experience.

Millman: This is one of the things that we forget and it's one of the things that I think gets people into trouble in relationships – that they assume that their sister had the same experience. And that if their sister doesn't see things they way that they do, that the sister is misperceiving events instead of really understanding that being different, coming at a different point in the family history, being treated differently by parents, occupying a different sibling position, all those things make your experience in the family very different.

Narrator: So Millman encourages adult sisters to step back and assess each other independently of how their parents did. For Science Today, I'm Larissa Branin.

E. Study Compares Therapies for High Risk Arthritis Patients

Narrator: This is Science Today. A UCLA study found that for high-risk arthritis patients, it's more cost-effective and safer to use a non-steroidal anti-inflammatory drug combined with what's called a proton pump inhibitor, which is an acid-lowering drug. This differs from the traditional guidelines recommended for this patient group, which was to treat them with Cox-2 inhibitors like Vioxx. Dr. Brennan Spiegel, who led the study, says it was conducted before Vioxx was removed from the market due to an increase in cardiovascular risk.

Spiegel: We actually did this study over a year before the FDA came out with their warning and at that time when we conducted this study, we knew that there were cardiovascular risks and we sought to include that in this sort of analysis.

Narrator: This is the first time a study looked at common, competing therapies and compared them head-to-head using computer analysis.

Spiegel: With this technology, we can use the best evidence that we have and combine all sorts of different information in a scientifically sound way and project what would happen if these two strategies were pitted against each other head-to-head.

Narrator: For Science Today, I'm Larissa Branin.