Horizontal and vertical rotational components of teleseismic surface and body waves are detected by large ring laser gyroscopes. This is illustrated with records from magnitudes 7.0 and 7.3 events at distances of 31 deg. and 42.6 deg. respectively. Phase comparisons with synchronous linear seismometer records confirm the gyroscopic coupling.
Coupling mechanisms and detection thresholds are discussed for ring laser gyroscope measurement of seismic rotation, and simultaneous records from a ring laser and a standard EARSS seismograph 230 km from an ML 5.3 seismic event are compared. Rotation dominates tilt and strain in modulating the Sagnac frequency, and microseisms are not significant. Power… (More)
BACKGROUND Postdiarrheal hemolytic uremic syndrome (HUS) is the most common cause of acute kidney failure among US children. The Foodborne Diseases Active Surveillance Network (FoodNet) conducts population-based surveillance of pediatric HUS to measure the incidence of disease and to validate surveillance trends in associated Shiga toxin-producing… (More)
Project Officers from the Prevention Program Branch, and the state, territorial, and local health departments that provided HIV testing data to the Centers for Disease Control and Prevention.
On the cover: A two fault, finite difference, numerical thermal model of the Dixie Valley Geothermal Field from Blackwell et al. solicitations are intended to generate research proposals in the areas of fracture permeability location and characterization, reservoir management and geochemistry. The work funded through these solicitations should stimulate the… (More)