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The 2014 Working Group on California Earthquake Probabilities (WGCEP14) present the time-independent component of the Uniform California Earthquake Rupture Forecast, Version 3 (UCERF3), which provides authoritative estimates of the magnitude, location, and time-averaged frequency of potentially damaging earthquakes in California. The primary achievements have been to relax fault segmentation and include multifault ruptures, both limitations of UCERF2. The rates of all earthquakes are solved for simultaneously and from a broader range of data, using a system-level inversion that is both conceptually simple and extensible. The inverse problem is large and underdetermined, so a range of models is sampled using an efficient simulated annealing algorithm. The approach is more derivative than prescriptive (e.g., magnitude-frequency distributions are no longer assumed), so new analysis tools were developed for exploring solutions. Epistemic uncertainties were also accounted for using 1440 alternative logic-tree branches, necessitating access to supercomputers. The most influential uncertainties include alternative deformation models (fault slip rates), a new smoothed seismicity algo-rithm, alternative values for the total rate of Mw >5 events, and different scaling relationships, virtually all of which are new. As a notable first, three deformation models are based on kinematically consistent inversions of geodetic and geologic data, also providing slip-rate constraints on faults previously excluded due to lack of geologic data. The grand inversion constitutes a system-level framework for testing hypotheses and balancing the influence of different experts. For example, we demonstrate serious challenges with the Gutenberg-Richter hypothesis for individual faults. UCERF3 is still an approximation of the system, however, and the range of models is limited (e.g., constrained to stay close to UCERF2). Never-theless, UCERF3 removes the apparent UCERF2 overprediction of M 6.5-7 earth-quake rates and also includes types of multifault ruptures seen in nature. Although UCERF3 fits the data better than UCERF2 overall, there may be areas that warrant further site-specific investigation. Supporting products may be of general interest, and we list key assumptions and avenues for future model improvements. [ABSTRACT FROM AUTHOR]

Background Grape phylloxera (Daktulosphaira vitifoliae) is one of the world's most important viticultural pests. However, the reproductive mode, genetic structure and host adaptation of phylloxera in various viticultural environments remains unclear. We examined reproductive mode and genetic structure of phylloxera by analyzing microsatellite makers across the samples from four vineyard-sites in California. Result The phylloxera populations in California are believed to have predominantly parthenogenetic reproduction. Therefore, genetic diversity of phylloxera is expected to be limited. However, this study showed high levels of diversity in Napa and Yolo county populations with a large number of unique genotypes, average number of alleles (2.1 to 2.9) and observed heterozygosities (0.330 to 0.388) per vineyard-sites. Reproduction diversity index (G: N- unique genotypes versus number of samples) ranged from 0.500 to 0.656 among vineyardsites. Both significant and non-significant Psex (probability of sexual reproduction) were observed among different repeated genotypes within each vineyard. Moreover, high variation of FIS was observed among different loci in each vineyard-site. Genetic structure analysis (UPGMA) and various measures of population differentiations (FST, PCA, and gene flow estimates) consistently separated AXR#1 (Vitis vinifera x V. rupestris-widely planted in California during the 1960s and 1970s) associated populations from the populations associated with other different rootstocks. Conclusion Genetic diversity, G: N ratio, Psex and FIS consistently suggested the occurrence of both parthenogenetic and sexual reproduction in California populations. This study clearly identified two major groups of phylloxera obtained from various rootstocks, with one group exclusively associated with only AXR#1 rootstock, defined as "biotype B", and another group associated with vinifera-based rootstocks, known as "biotype A". [ABSTRACT FROM AUTHOR]

We present a new three-dimensional (3D) compressional wavespeed (Vp) model for the Parkfield region, taking advantage of the recent seismicity associated with the 2003 San Simeon and 2004 Parkfield earthquake sequences to provide increased model resolution compared to the work of Eberhart-Phillips and Michael (1993) (EPM93). Taking the EPM93 3D model as our starting model, we invert the arrival-time data from about 2100 earthquakes and 250 shots recorded on both permanent network and temporary stations in a region 130 km northeast--southwest by 120 km northwest--southeast. We include catalog picks and cross-correlation and catalog differential times in the inversion, using the double-difference tomography method of Zhang and Thurber (2003). The principal Vp features reported by EPM93 and Michelini and McEvilly (1991) are recovered, but with locally improved resolution along the San Andreas Fault (SAF) and near the active-source profiles. We image the previously identified strong wavespeed contrast (faster on the southwest side) across most of the length of the SAF, and we also improve the image of a high Vp body on the northeast side of the fault reported by EPM93. This narrow body is at about 5- to 12-km depth and extends approximately from the locked section of the SAF to the town of Parkfield. The footwall of the thrust fault responsible for the 1983 Coalinga earthquake is imaged as a northeast-dipping high wavespeed body. In between, relatively low wavespeeds (<5 km/sec) extend to as much as 10-km depth. We use this model to derive absolute locations for about 16,000 earthquakes from 1966 to 2005 and high-precision double-difference locations for 9,000 earthquakes from 1984 to 2005, and also to determine focal mechanisms for 446 earthquakes. These earthquake locations and mechanisms show that the seismogenic fault is a simple planar structure. The aftershock sequence of the 2004 mainshock concentrates into the same structures defined by the pre-2004 seismicity, confirming earlier observations (Waldhauser et al., 2004) that the seismicity pattern at Parkfield is long lived and persists through multiple cycles of mainshocks. [ABSTRACT FROM AUTHOR]

The Calaveras and Hayward faults are major components of the San Andreas fault system in the San Francisco Bay region. Dextral slip is presumed to transfer from the Calaveras fault to the Hayward fault in the Mission Hills region, an area of uplift in the contractional stepover between the two faults. Here the estimated deep slip rates drop from 15 to 6 mm/yr on the Calaveras fault, and slip begins on the Hayward fault at an estimated 9 mm/yr. A lineament of microseismicity near the Mission fault links the seismicity on the Calaveras and Hayward faults and is presumed to be related directly to this slip transfer. However, geologic and seismologic evidence suggest that the Mission fault may not be the source of the seismicity and that the Mission fault is not playing a major role in the slip transfer. We perform a joint inversion for hypocenters and the 3D P-wave velocity structure of the stepover region using 477 earthquakes. We find strong velocity contrasts across the Calaveras and Hayward faults, corroborated by geologic, gravity, and aeromagnetic data. Detailed examination of two seismic lineaments in conjunction with the velocity model and independent geologic and geophysical evidence suggests that they represent the southern extension of a northeasterly dipping Hayward fault that splays off the Calaveras fault, directly accounting for the deep slip transfer. The Mission fault appears to be accommodating deformation within the block between the Hayward and Calaveras faults. Thus, the Calaveras and Hayward faults need to be considered as a single system for developing rupture scenarios for seismic hazard assessments. [ABSTRACT FROM AUTHOR]

Studies the band of seismicity located between two earthquakes that occurred at Kern County and Walker Pass in California. Interpretation of the seismic lineament as a strike-slip fault; Relocation and calculation of focal mechanisms of the earthquakes.

Emergency department thoracotomy (EDT) is a dramatic lifesaving procedure demanding timely surgical intervention, technical expertise, and coordinated resuscitation efforts. Inappropriate use is costly and futile. All patients admitted to a Level II trauma center who underwent EDT from January 2003 to July 2012 were studied. The primary end point was appropriateness of EDT. Secondary end points were staff exposure, survival, and return to normal function. Eighty-seven patients including 59 patients with penetrating wounds had a mean loss of vital signs (LOV) 11.6 ±10.6 minutes and Injury Severity Score (ISS) of 45.8 ± 16.1, whereas 28 blunt injury patients had a mean LOV of 10.4 ± 11.5 minutes and ISS of 50.4 ± 19.4. Mortality was 81 per cent (48 of 59) in penetrating injury and 93 per cent (26 of 28) in blunt injury patients, respectively (odds ratio [OR] 2.99; P 0.21). Fifty-five EDTs were indicated with 10 survivors (18.2%) and 32 not indicated with three survivors (9.4%). Surgeons adhered to guidelines more compared with ED physicians (OR, 4.9; P = 0.03) whose patients were more likely to die (OR, 3.52; P = 0.124). Survivors (11 of 13 [84.6%]) were discharged home without significant long-term neurologic disability. EDT is lifesaving when performed for penetrating injury by experienced surgeons following established guidelines but futile in blunt injury or when performed by nonsurgeons regardless of mechanism.