B. Functional MRIs May Benefit from Vision Science Research

Narrator: This is Science Today. New findings by vision scientists at the University of California, Berkeley, may significantly improve the resolution of brain scans from functional magnetic resonance imaging, or fMRI. Jeffrey Thompson, a vision science graduate student who led the study, says fMRI's generally focus on an increase in blood flow in various parts of the brain on a relatively large scale.

Thompson: So what we did was we measured oxygen levels in the tissue in a very localized spot in the brain and also the same time, we were able to measure the actual neural activity that's going on in that area.

Narrator: The researchers found that an initial dip in oxygen levels at a micrometer scale is an earlier, more precise signal of nerve cell activity than the current measure of blood flow on a millimeter scale.

Thompson: What we hope it implies is that if we zero in on this initial dip in oxygen with the fMRI, that we could basically increase the spatial resolution of fMRI, which would have implications for examining neural circuits at a much finer scale than what we are currently able to do.

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

C. Advances in Brain Tumor Surgery

Narrator: This is Science Today. There are two crucial elements to successful brain tumor surgery - the removal of the tumor and causing no harm to critical areas of the brain. Dr. Neil Martin, chief of the UCLA Neurosurgery Division, says in the past, it was difficult for surgeons to visually see the margin of the tumor.

Martin: We now have an operating room with an MRI scanner in it. So we remove the tumor, simply pivot the patient, get a scan and if there's anything left we take it out immediately. It's really made a major difference in the success of removing tumors of this sort.

Narrator: To ensure no damage is done, patients can even be operating on while awake.

Martin: Surprisingly, you can numb the pain sensitive structures in the scalp and the head and operate on the brain without the patient experiencing any discomfort and that allows us to test them, to ask them to speak, to read, identify objects while we're actually working to make sure that those critical language functions are preserved and that none of those are injured as the tumor's removed.

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

D. How Microsensors May Change Farm Life

Narrator: This is Science Today. Researchers at the University of California, Berkeley, are developing the cutting-edge of agri-business-a technology of networked microchip sensors that can closely monitors farms. David Culler, a professor of computer science and an expert in this technology, explains how wireless microsensors may dramatically change life on the farm.

Culler: That same notion of monitoring, or dense monitoring of space, if you take it out to the farm, that's what agri-business-you can imagine precision agriculture, where you really would like to control how you're watering, how you're fertilizing in response to the actual soil moisture, how it drains, the sun, the wind, that kind of thing.

Narrator: Culler says that by strategically placing microsensors on their farm, growers can get an enhanced picture of the physical changes and activities that occur across space and time.

Culler: If you think about agri-business, there's this whole flow of different kind of input: seeds, fertilizer, soils, water, so forth. You want to know where they are all coming from. How do they then get distributed to the places they are needed? Are the crates where the berries are being picked? How do all the pieces come together at the right time?

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

E. A New Test Targets Various Sources of Lead Exposure in Children

Narrator: This is Science Today. A new technique that detects the chemical "fingerprints" of different sources of lead exposure may help researchers zero in on the causes of childhood lead poisoning, which is typically hard to do. Donald Smith, a professor of environmental toxicology at the University of California, Santa Cruz, tested the technique and says even though the United States has greatly reduced the major sources of lead, a large number of children still suffer from lead poisoning.

Smith: Because we've used lead for so long in a number of different industrial materials, including as an additive in gasoline. As a result of all those industrial activities and the use of lead as combustion in cars, there's enormous amounts of lead, essentially stockpiled in the dust and soil of urban areas.

Narrator: Another major source of lead exposure in children is lead-based paints in old, deteriorating housing.

Smith: The most prudent thing that parents can do to help reduce that potential exposure is just to be aware of how the children may be exposed and how they can, by keeping their environment clean - whether it be the household or the outside environment - how they can actually reduce the intake of lead to the child.

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