A. Scientists Solve a Puzzling Aspect about Prions

Narrator: This is Science Today. A prion is an infectious protein that causes disease not by the DNA or RNA of a virus or bacteria, but on the basis of their shape. One of the most puzzling aspects about prions has been if they have no genetic material, how can a single prion exist in different strains that can cause different diseases? Now, scientist Jonathan Weissman of the University of California, San Francisco has solved that puzzle by working with baker’s yeast as a model organism.

Weissman: We took precisely the same protein and misfolded it into two different shapes. And we actually did this by just changing the temperature. We misfolded it at four degrees or at thirty-seven degrees, and it misfolded into two different shapes.

Narrator: The scientists then infected the baker’s yeast with these two different shapes of the same protein – the result was strikingly different prion strains.

Weissman: And I think the next step is, more broadly, how often you see proteins misfolding into different conformations in much more common diseases of misfolding like Alzheimer’s disease.

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

B. Worried About Not Getting Enough Sleep?

Narrator: This is Science Today. As a society, we tend to operate in overdrive – working long hours and juggling family or leisure activities. In the process, many of us are sleep deprived – or at least, that’s what we think. According to sleep expert, Daniel Kripke of the University of California, San Diego, it turns out that people who sleep eight hours or more have a higher risk of death from heart disease, stroke and cancer, than those who sleep seven hours or less.

Kripke: I wish we knew what the reason is, we really don’t. It might be that something that causes long sleep also causes deaths, but it’s independent of the long sleep. So it’s important to understand that we don’t know that a long sleeper will live longer if they shorten their sleep or set the alarm clock earlier. What we can say is that there doesn’t seem to be any risk of their shortening their time in bed.

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

C. Veterinary Schools Address the Care of Animals in Shelters

Narrator: This is Science Today. Behavior is a very significant reason for the breakdown of the human-animal bond and one of the primary reasons animals end up in shelters. Kate Hurley, director of Maddie’s Shelter Medicine Program at the University of California, Davis, says animals with behavior problems – whether it’s urination in the house or aggression with other people – are the hardest animals to place.

Hurley: If the original owner didn’t want to work with that behavior problem, now that animal is subjected to the stressful shelter environment and then you try and place it in a new home with that behavioral problem and someone who wants to take that on and that can be very challenging to find those homes.

Narrator: UC Davis, along with other schools around the country, is starting to address shelter medicine by dealing with behavioral problems and treating sick animals while still in the shelter environment.

Hurley: We have to figure out how to have a cat not catch a cold in an animal shelter and in figuring that out, that could literally save hundreds of thousands of lives every year and these are young, healthy animals with their whole lives ahead of them.

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

D. The History and Evolution of Peening Metal

Narrator: This is Science Today. Peening is an ancient process used to harden metals. Historically, hand peening was used to make tools and armor.

Hackel: Peening goes way back to mankind sort of empirically figured out that if you pounded certain metals, they actually lasted longer for him. And he invented the ball peen hammer, this little round-ended hammer that he would pound the metal with and if he appropriately pounded it, he found it wouldn’t crack as much and so people would use this process.

Narrator: Lloyd Hackel, program leader of the Laser Science and Technology division at the Lawrence Livermore National Laboratory, says peening has come a long way since then. Shot peening was introduced in the 1940s and in the 1970s, laser peening began. More recently, Hackel and his group developed a highly advanced laser peening technology that’s proven to be very beneficial for commercial and military aircraft parts.

Hackel: We’ve been developing this process since 1996 – perfecting it, making it work, understanding what it would have to be for an industrial application.

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

E. How Buildings May Some Day be Self-Tagging

Narrator: This is Science Today. Engineers at the University of California, Berkeley, are collaborating on technology to make buildings, bridges and other structures ‘smarter’. As part of the Center for Information Technology Research in the Interest of Society, or CITRIS, program, engineer Steve Glaser is working with smart dust motes – or tiny sensor devices – to monitor a building’s structural integrity.

Glaser: It allows us to analyze the expected ground motions more accurately than the techniques being used today. This would allow us to predict the motions that our structures will see, which is very important for proper design.

Narrator: In the future, Glaser says thousands of smart dust motes could be placed in a building to render them ‘self-tagging’ in the case of damage.

Glaser: Because the big economic cost of an earthquake isn’t necessarily the immediate damage, you would have to clear out all public buildings until engineers can come an inspect. That might be six to eight months, a year, which is a tremendous loss not only to the company, but to the people who aren’t getting paid.

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