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The 1989 Mw 6.9 Loma Prieta earthquake is the first major event to occur along the San Andreas fault (SAF) zone in central California since the 1906 M 7.9 San Francisco earthquake. Given the complexity of this event, uncertainty has persisted as to whether this earthquake ruptured the SAF itself or a secondary fault. Recent work on the SAF in the Coachella Valley in southern California has revealed similar complexity, arising from a nonplanar, nonvertical fault geometry, and has led us to reexamine the Loma Prieta event. We have compiled data sets and data analyses in the vicinity of the Loma Prieta earthquake, including the 3D seismic velocity model and aftershock relocations of Lin and Thurber (2012), potential field data collected by the U.S. Geological Survey following the earthquake, and seismic refraction and reflection data from the 1991 profile of Catchings et al. (2004). The velocity model and aftershock relocations of Lin and Thurber (2012) reveal a geometry for the SAF that appears similar to that in the Coachella Valley (although rotated 180°): at Loma Prieta the fault dips steeply near the surface and curves with depth to join the moderately southwest-dipping main rupture below 6 km depth, itself also nonplanar. The SAF is a clear velocity boundary, with higher velocities on the northeast, attributable to Mesozoic accretionary and other rocks, and lower velocities on the southwest, attributable to Cenozoic sedimentary and volcanic rocks of the La Honda block. Rocks of the La Honda block have been offset right-laterally hundreds of kilometers from similar rocks in the southern San Joaquin Valley and vicinity, providing evidence that the curved northeast fault boundary of this block is the plate boundary. Thus, we interpret that the Loma Prieta earthquake occurred on the SAF and not on a secondary fault. [ABSTRACT FROM AUTHOR]

The Clear Lake Volcanic Field in northern California is the youngest and northern-most part of a long-lived volcanic system that has produced recent (~10 ka) eruptions. Adjacent to the Clear Lake Volcanic Field is the world's largest energy producing geothermal field, The Geysers. The hottest part of The Geyser's geothermal field is in the northwest where temperatures reach ~400 °C at 3 km depth. Low permeability, high thermal gradients, and low steam saturation prescribed development of an enhanced geothermal system (EGS) in the Northwest Geysers to increase energy producing capacity. Though the Northwest Geysers is known to be the hottest part of the field, geophysical methods have failed to adequately image any inferred heat source. This project aims to image the heat source of the Northwest Geysers using newly collected gravity and magnetotelluric (MT) measurements. Gravity data were jointly modeled with existing magnetic data along a two-dimensional profile aligned with an existing geologic cross-section. The key feature of the potential field model is a low-density, low-susceptibility body at 5 km depth (bmsl) under the EGS. MT data were modeled in three-dimensions to characterize subsurface resistivity structure, where the upper 3 km of the resistivity model agrees well with existing data. Lithologic and steam saturation are estimated from modeled resistivity values using existing geophysical data. Below 3 km depth (bmsl), the resistivity model images a possible young intrusion under the EGS. A possible zone of partial melt (<5%) below 7 km depth (bmsl) in the northwestern part of the field is also imaged which extends northeast towards the main part of the Clear Lake Volcanic Field. • Magnetotellurics successfully images the Northwest Geysers geothermal field. • Steam saturation is directly related to electrical resistivity. • The heat source is 7 km below the northwest part of the geothermal field. • A boundary between the west and east parts of the geothermal field is imaged. • The Geysers Plutonic Complex is imaged as extending northwards below 3 km. [ABSTRACT FROM AUTHOR]

This study assessed the potential for a high-temperature blind geothermal system in southeastern Gabbs Valley, an area with no previous geothermal exploration, by utilizing geothermal play fairway analysis. Gabbs Valley is a structurally complex, tectonically active basin occupying a transtensional displacement transfer zone. Multiple lines of evidence suggest the presence of a blind geothermal system, including collocated intersecting gravity gradients, magnetic-low, low-resistivity, 2-m temperature anomaly, and 130–140 °C geothermometers obtained from nearby agricultural wells. Six 150 m-deep temperature-gradient holes were drilled to target the geophysical and thermal anomalies. Two holes produced bottom-hole temperatures of 114.5 °C and 124.9 °C. Drilling results establish the discovery of a blind geothermal system. Power estimates based on resource conceptual models of the geothermal system suggest a median (P50) capacity of ∼16 MWe. [ABSTRACT FROM AUTHOR]

Against a backdrop of accelerating digital innovation in nature conservation and environmental management, a real-world experiment was conducted with the research aims of assessing: 1) the effects of introducing a digital data-entry platform on volunteer data submission; and 2) the extent to which coordinators influence digital platform use by their volunteers. We focussed on a large-scale volunteer-based initiative aimed at eradicating the non-native American mink (Neovison vison) from northern Scotland. This geographically dispersed conservation initiative adopted a digital platform that allowed volunteers to submit records to a central database. We found that the platform had a direct and positive effect on volunteer data submission behaviour, increasing both the number and frequency of submissions. However, our analysis revealed striking differences in coordinator engagement with the platform, which in turn influenced the engagement of volunteers with this centrally introduced digital innovation. As a consequence, the intended organisation-wide rolling out of a digital platform translated into a diversely-implemented innovation, limiting the efficacy of the tool and revealing key challenges for digital innovation in geographically-dispersed conservation initiatives., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Randomised controlled trials (RCT) can struggle to recruit to target on time. This is especially the case with hard to reach populations such as those with severe mental ill health. The SCIMITAR+ trial, a trial of a bespoke smoking cessation intervention for people with severe mental ill health achieved their recruitment ahead of time and target. This article reports strategies that helped us to achieve this with the aim of aiding others recruiting from similar populations., Methods: SCIMITAR+ is a multi-centre pragmatic two-arm parallel-group RCT, which aimed to recruit 400 participants with severe mental ill health who smoke and would like to cut down or quit. The study recruited primarily in secondary care through community mental health teams and psychiatrists with a smaller number of participants recruited through primary care. Recruitment opened in October 2015 and closed in December 2016, by which point 526 participants had been recruited. We gathered information from recruiting sites on strategies which led to the successful recruitment in SCIMITAR+ and in this article present our approach to trial management along with the strategies employed by the recruiting sites., Results: Alongside having a dedicated trial manager and trial management team, we identified three main themes that led to successful recruitment. These were: clinicians with a positive attitude to research; researchers and clinicians working together; and the use of NHS targets. The overriding theme was the importance of relationships between both the researchers and the recruiting clinicians and the recruiting clinicians and the participants., Conclusions: This study makes a significant contribution to the limited evidence base of real-world cases of successful recruitment to RCTs and offers practical guidance to those planning and conducting trials. Building positive relationships between clinicians, researchers and participants is crucial to successful recruitment.

Context: In 2014, laughter yoga (LY) achieved the intermediate level, tier 2, under the Title III-D Evidence-based Disease Prevention and Health Promotion Program through the Administration on Aging (AOA). Further research is needed to qualify LY under the criteria for the highest tier, tier 3, to assure continued funding for LY classes at senior centers., Objectives: The study intended to demonstrate further the benefits of LY and to qualify LY as tier 3 under Title III-D., Design: Using a quasi-experimental design, the research team conducted a preintervention/postintervention study in 3 phases., Setting: The study was done in a variety of community centers. Phase 1, a pilot phase, was limited to North Carolina, and phase 2 was conducted in multiple states. Phase 3 was held at the North Carolina Area Agency on Aging's annual Volunteer Appreciation meeting., Participants: Participants in phases 1 (n = 109) and 2 (n = 247) enrolled in LY classes. Classes were advertised by fliers posted in community and in retirement centers. The ability of participants to participate in a class was based solely on their desire to participate, regardless of age, ability, health status, or physical impairment. Phase 3 (n = 23) was a convenience sample only. All phases were voluntary., Outcome Measure: The pre- and posttests for all 3 phases were Likert-scale surveys, 10 questions on the Psychological Outcomes of Well-being (POWB) survey. Pulse and other physiological measurements were also assessed pre- and postintervention. Analysis included a t test on each of the 10 POWB and physiological measures for all phases., Results: All 10 POWB measures for phases 1 and 2 showed significant improvements between the pre- and postintervention testing (P < .001). Phase 3, the control, showed no significant improvement., Conclusions: The initial study demonstrated that LY meets the criteria to qualify for tier 3 under the Title III-D Evidence-based Disease Prevention and Health Promotion Program and that a large number of Americans, regardless of age and physical ability, could benefit from LY.

Experimental techniques for electron energy loss spectroscopy (EELS) combine high energy resolution with high spatial resolution. They are therefore powerful tools for investigating the local electronic structure of complex systems such as nanostructures, interfaces and even individual defects. Interpretation of experimental electron energy loss spectra is often challenging and can require theoretical modelling of candidate structures, which themselves may be large and complex, beyond the capabilities of traditional cubic-scaling density functional theory. In this work, we present functionality to compute electron energy loss spectra within the onetep linear-scaling density functional theory code. We first demonstrate that simulated spectra agree with those computed using conventional plane wave pseudopotential methods to a high degree of precision. The ability of onetep to tackle large problems is then exploited to investigate convergence of spectra with respect to supercell size. Finally, we apply the novel functionality to a study of the electron energy loss spectra of defects on the (1 0 1) surface of an anatase slab and determine concentrations of defects which might be experimentally detectable.

The rapid detection of Listeria monocytogenes contamination in food is essential to prevent food-borne illness in humans. The aim of this study was to differentiate non-contaminated milk from milk contaminated with L. monocytogenes using enzyme substrates coupled with the analysis of volatile organic compounds (VOCs). The method is based on the activity of β-glucosidase and hippuricase enzymes and the detection of a specific VOC i.e. 2-nitrophenol and 3-fluoroaniline, respectively. VOCs were extracted, separated and detected by headspace-solid phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME GC-MS). This approach required the inclusion of the selective agent's cycloheximide, nalidixic acid and acriflavine HCl in the growth medium to inhibit interfering bacteria. The VOCs were liberated by L. monocytogenes provided that samples contained at least 1-1.5×10(2) CFU ml(-1) of milk prior to overnight incubation. This approach shows potential for future development as a rapid method for the detection of L. monocytogenes contaminated milk., (Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.)