SSRL Science Highlights Archive

Approximately 1,700 scientists visit SSRL annually to conduct experiments in broad disciplines including life sciences, materials, environmental science, and accelerator physics. Science highlights featured here and in our monthly newsletter, Headlines, increase the visibility of user science as well as the important contribution of SSRL in facilitating basic and applied scientific research. Many of these scientific highlights have been included in reports to funding agencies and have been picked up by other media. Users are strongly encouraged to contact us when exciting results are about to be published. We can work with users and the SLAC Office of Communication to develop the story and to communicate user research findings to a much broader audience. Visit SSRL Publications for a list of the hundreds of SSRL-related scientific papers published annually. Contact us to add your most recent publications to this collection.

SCIENCE HIGHLIGHT BANNER IMAGES

October 2004
Wayne W. Lukens, David K. Shuh, Norman C. Schroeder, Kenneth R. Ashley
Figure 1.

The Hanford nuclear waste site in southeastern Washington State is one of the most contaminated sites in the DOE complex. It stores millions of gallons of radioactive waste from the nation's nuclear weapons programs. High-level radioactive waste is leaking from about a third of Hanford's underground tanks.

BL4-1, BL11-2
October 2004
Eugenio Santelli, Laurie A. Bankston, Stephen H. Leppla, Robert C. Liddington
Figure 1.

X-ray images have revealed how anthrax hijacks important cell machinery to enter and destroy human cells. Researchers from The Burnham Institute and the National Institute of Allergy and Infectious Diseases discovered the structure of an anthrax toxin bound with a cell receptor using data taken at SSRL. The clearer picture of how anthrax works brings researchers closer to the development of a therapy against anthrax infection as well as a new cancer therapeutic.

Macromolecular Crystallography
BL9-2
September 2004
Elitza I. Tocheva, Michael E. P. Murphy
Figure 1.

Nitric oxide (NO) is a small but powerful biologically active molecule that can protect or destroy cells. The bacterial enzyme that creates NO can, however, also turn nitrogen fertilizers into ozone-depleting NO and nitrous oxide, a greenhouse gas. Researchers at the University of British Columbia now have a better understanding of how that enzyme, nitrite reductase (NiR), works. Elitza Tocheva and Michael Murphy used SSRL's macromolecular crystallography facilities to study difficult-to-prepare crystal complexes of NiR bound to NO or to nitrite (which NiR turns into NO).

Macromolecular Crystallography
BL7-1
September 2004
Douglas S. Daniels, Tammy T. Woo, Kieu X. Luu, David M. Noll, Neil D. Clarke, Anthony E. Pegg, John A. Tainer
Figure 1.

Error-free DNA replication depends on the maintenance of the correct chemical structure of each component base. Bases with altered structures may mispair during the replication process, causing mutations. One common chemical alteration is the addition of an alkyl group to guanine, causing mispairing to thiamine during replication.

Macromolecular Crystallography
BL9-1
August 2004
Michael T. Green, John H. Dawson, Harry B. Gray
Figure 1. The rebound mechanism of cytochrome P450.

Chloroperoxidase is one of a large class of heme proteins that play important roles in a number of physiological processes, including xenobiotic metabolism, neurological development, blood pressure control, and immune defense. These heme protein systems all have the ability to oxygenate saturated hydrocarbons under ambient conditions, a process which is chemically quite challenging, and hence is also of industrial importance.

BL7-3
August 2004
James Stevens, Ian A. Wilson
Figure 1. Ribbon representation of the hemagglutinin HA0 trimer from the 1918 influenza virus.

Researchers have literally unearthed clues as to why the 1918 influenza pandemic was so deadly. The 1918 influenza pandemic ranks as the largest and most destructive outbreak of an infectious disease, killing 20 to 40 million people worldwide. Using fragments of the flu genome from Alaskan victims preserved by permafrost and army autopsy tissues, James Stevens and Ian Wilson of the Scripps Research Institute in La Jolla, California and their collaborators have assembled genes from the 1918 flu virus.

Macromolecular Crystallography
BL9-2
July 2004
Anneli Munkholm (Lumileds Lighting), Sean Brennan (SSRL)
Figure 1.

New evidence is overturning the assumption that the thermal oxide grown on single crystal silicon is completely amorphous. SSRL researchers Anneli Munkholm (now at Lumileds Lighting) and Sean Brennan recently published work in Physical Review Letters showing that there is residual order within the oxide. The thermal oxide film on silicon has been studied extensively for decades because these oxides form the basis of most of the integrated circuits used in modern electronics. The new results have implications for theoretical models of the oxidation process.

X-ray scattering
July 2004
Benjamin Gilbert, Feng Huang, Hengzhong Zhang, Glenn A. Waychunas, Jillian F. Banfield
Figure 1.

Extremely small pieces of a material aren't always a chip off a bigger block. How nanomaterials behave is tremendously important to know when trying to understand the roles of mineral nanoparticles in the environment, or design devices for nanotechnology. Researchers taking data at SSRL and the Advanced Photon Source (APS) in Illinois recently found that zinc sulfide at 3.5 nanometers (nm) in size (3.5 billionths of a meter) behaves quite differently than "bulk" zinc sulfide (several hundred nm and up). The method they developed should also prove useful for studying other kinds of nanomaterials.

Materials Small-angle X-ray Scattering (SAXS)
BL1-4
June 2004
Thiang Yian Wong, Robert Schwarzenbacher, Robert C. Liddington
Figure 1.

Anthrax makes a deadly cocktail of three toxin proteins that flood the bloodstream, leading to rapid death if the infection is not diagnosed and treated in its early stages. Even antibiotic treatments can fail when the Anthrax bacterium, Bacillus anthracis, has already produced lethal levels of toxins. The poisonous protein called Lethal Factor (LF) rapidly blocks signals to recruit immune cells to fight the infection. Another enzyme Edema Factor (EF) causes the release of fluid into the lungs and is deadly on its own. 

Macromolecular Crystallography
BL7-1, BL9-1
May 2004
I. Tudosa, H. C. Siegmann, J. Stöhr
Figure 1.

Two important goals of technology are: smaller and faster. In line with this goal the 50 billion dollar per year magnetic recording industry has long wondered where it would run into obstacles set by fundamental physical principles. The basic questions concern the lateral sizes at which the magnetic domains that define the "1" and "0" bits become unstable and whether there is a speed limit for the writing process of the bits.

Pages

Subscribe to SSRL Science Highlights
Find Stanford Synchrotron Radiation Lightsource on FlickrFind Stanford Synchrotron Radiation Lightsource on YouTubeFind Stanford Synchrotron Radiation Lightsource on Twitter