A. A New Discovery about Probiotics, The ‘Good’ Bacteria

Narrator: This is Science Today. Probiotics, which are often consumed as live microorganisms in products such as yogurt, are ‘good bacteria’ that have been found to aid disorders such as Inflammatory Bowel Disease, or IBD. Now, Dr. Eyal Raz of the University of California, San Diego has discovered the bacteria is just as effective when it’s inactivated through the process of gamma radiation.

Raz: Irradiation, what it does is it reduces the metabolic activity to almost zero and it doesn’t modify the cell surface as heat kill does to the bacteria. So when we use this irradiated bacteria, we found it works as good as viable bacteria.

Narrator: Currently, probiotics cannot be used in most food products because the bacteria are metabolically active and will induce fermentation.

Raz: But when you irradiate them, you can actually add them as a food supplement to anything you want because they are not going to affect the taste and the consistency and the structure of this food.

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

B. Insight into the Institution of Marriage

Narrator: This is Science Today. The stereotypical, old-fashioned view of marriage is that a man wants a woman who can provide children and a woman wants a man who can provide enough money for the family. But Monique Borgerhoff-Mulder, an anthropology professor at the University of California, Davis says recent studies indicate that men and women are choosing mates who share similar values.

Borgerhoff-Mulder: We have this view of marriage as a division of labor. So when you find that men and women like the same kinds of characteristics in that partner as they view they have in themselves as well, it kind of puzzles this whole notion of the division of labor, but actually if you think about the way that marriage is going in this culture, we think of marriage more as a relationship of companionship rather than necessary division of labor. And so in some respects, it makes sense.

Narrator: Borgerhoff-Mulder adds that the institution of marriage adapts to the changing economic roles and opportunities of men and women. For Science Today, I’m Larissa Branin.

C. A New Realm of Magnetic Resonance Imaging

Narrator: This is Science Today. Nuclear magnetic resonance is the physical phenomenon that underlies its more modern incarnation, magnetic resonance imaging or MRI. Scientist Alexander Pines of the Lawrence Livermore National Laboratory describes what nuclear magnetic resonance means.

Pines: Nuclear, because it has to do with the nucleus, not radioactive properties; magnetic because it has to do with magnetism and applied magnetic fields; and resonance because of the characteristic resonance frequencies that constitute the spectrum of that molecule in the field.

Narrator: Pines, a pioneering nuclear magnetic resonance researcher, has discovered a new technique called remote detection, which would improve the sensitivity and versatility of MRIs.

Pines: What one is doing in remote – one is doing a freeze frame of the different instance and each different instant is encoded, taken out, then the whole thing is assembled into the reconstructive, time dependent signal or sound.

Narrator: Pines adds that such unrestrained technology opens up a new realm of imaging possibilities. For Science Today, I’m Larissa Branin.

D. An Observatory for Detecting Gravitational Waves

Narrator: This is Science Today. Gravitational waves are ripples in space and time, which were predicted by Einstein in his Theory of General Relativity. Physicist Lars Bildsten of the University of California, Santa Barbara says these gravitational waves are produced by violent events in the distant universe – such as the collision of two black holes or by the cores of supernova explosions.

Bildsten: These are waves in the gravitational field – they are not electromagnetic waves like what the radio listener is using to get the signal right now.

Narrator: These cosmic gravitational waves carry with them insightful information about their origins and the nature of gravity, so physicists look forward to the findings of a detection facility called the Laser Interferometer Gravitational-Wave Observatory.

Bildsten: The acronym for that is LIGO – it’s two large interferometers. And those two interferometers were constructed by the National Science Foundation under the work of both Cal Tech and MIT. And they are presently operating and searching for gravitational waves in the universe from many different types of sources.

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

E. Using Computer Models to Better Understand Ozone Concentrations

Narrator: This is Science Today. Limiting ozone concentrations is an important goal because ozone is a highly reactive, toxic gas that damages our lungs, materials and crops. Scientists at the Lawrence Livermore National Laboratory’s Atmospheric Science Division have created a computer model to better understand the sources of ozone. Physicist Cyndi Atherton says this is important to know because how we regulate and control emissions will depend on that.

Atherton: So what we’re trying to do is look realistically at how much ozone are we forming from hydrocarbons and nitrogen oxides reacting. How much of that can we control versus how much of that is coming from high above?

Narrator: Atherton makes sure the emissions that are entered into the computer model are realistic and accurate.

Atherton: I do a lot of looking at our results and understanding how those compare to actual observations and if they do compare well, why and if they don’t, what are we missing, either physically or chemically? So that we think that we have a robust model that you can believe if we were in situations other than those we can extrapolate.

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