High‐rate (1‐Hz) Global Positioning System (GPS) data are beginning to be used for a variety of geophysical monitoring purposes, including seismology. Improving the precision of high‐rate GPS position estimates will increase the value of these 1‐Hz GPS monitoring systems. One technique that has been used to improve high‐rate GPS positioning takes advantage of the ground track repeat period of the satellites. This study investigates the GPS orbital repeat period and determines that it varies for each satellite and differs significantly from the generally assumed sidereal period. Orbit repeat periods are calculated and used to filter 1‐Hz GPS position estimates. Using the calculated orbit repeat period significantly reduces low frequency (0.001–0.04 Hz) errors in 1‐Hz GPS position estimates.

The most common CT finding in patients with SLE and acute abdominal pain is ischemic bowel disease. CT is useful for detecting the primary cause of gastrointestinal symptoms, planning treatment, and monitoring for infarction or perforation.

The 68% fulfillment of criteria for authorship was closely related to the large number of researchers contributing to one category or to categories belonging to the same ICMJE criterion.

Radiographically evident PEs are uncommonly observed following EIS and appear to be more common in patients receiving a higher volume of liquid acrylate. Affected patients were either mildly symptomatic or asymptomatic, and there were no direct fatalities of this complication.

[1] High-rate GPS has the potential to recover both dynamic and static displacements accurately. We analyze 1-Hz GPS data recorded during the 2003 Tokachi-Oki earthquake. The 1-Hz GPS displacement waveforms show good agreement with integrated accelerometer records except for low frequency noise that are inherently present in integrated seismic records. The GPS waveforms were inverted to model the spatio-temporal evolution of the fault slip during the rupture. The slip is found to propagate downdip in the subduction zone with largest moment release $50 km northwest of the hypocenter. The region of largest slip agrees in general with traditional seismic studies, indicating that 1-Hz GPS can be used for finite fault studies. The 1-Hz GPS slip model shows clearer contrast with afterslip distributions than those inferred from strong motion data, possibly because 1-Hz GPS is more sensitive to cumulative slip distribution.

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[1] The slip history of the 2003 San Simeon earthquake is constrained by combining strong motion and teleseismic data, along with GPS static offsets and 1-Hz GPS observations. Comparisons of a 1-Hz GPS time series and a co-located strong motion data are in very good agreement, demonstrating a new application of GPS. The inversion results for this event indicate that the rupture initiated at a depth of 8.5 km and propagated southeastwards with a speed $3.0 km/sec, with rake vectors forming a fan structure around the hypocenter. We obtained a peak slip of 2.8 m and total seismic moment of 6.2 Â 10 18 Nm. We interpret the slip distribution as indicating that the hanging wall rotates relative to the footwall around the hypocenter, in a sense that appears consistent with the shape of the mapped fault trace.

Retrieving displacement from seismic acceleration records is often difficult because unknown small baseline offsets in the acceleration time series will contaminate the doubly integrated record with large quadratic errors. One-hertz Global Positioning System (GPS) position estimates and collocated seismic data are available from the 2003 M w 8 Tokachi-Oki (Hokkaido) earthquake. After a process of correcting for possible misorientation of the seismic sensors, an inversion method is used to simultaneously solve for ground displacement with both data sets as input constraints. This inversion method takes into account the presence of unknown offsets in the acceleration record, and the relatively large uncertainties in the estimated 1-Hz GPS positions.In this study, 117 channels of seismic data were analyzed. Only 5% of the time does the static displacement retrieved from traditional baseline correction processing without GPS information agree with the absolute displacement measured with 1-Hz GPS to within the errors of the GPS data. In solving simultaneously for constrained displacements that agree with both the seismic and GPS data sets, an optimal solution was found that included only one-or two-step functions in the acceleration records. Potential explanations for the offsets are analyzed in terms of tilt of the sensor or electronic noise. For nine stations, clear misorientations of the seismic sensors of more than 20 deg from the reported orientation were found. For this size event, the 30-sec sampled GPS solutions were also a sufficient constraint for establishing the offset errors and recovering reliable displacements. The results significantly extend the frequency band over which accelerometer data are reliable for source inversion studies.Online material: Plots of constrained seismograms with metadata.