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The article focuses on review papers regarding the development of a national strategy for suicide prevention. It states that the Suicide Prevention Advocacy Network (SPAN) commissioned the papers for a national conference about suicide prevention that was held in Reno, Nevada in October 1998. It mentions that the strategy aims to determine, support, and coordinate integrated programs against suicidal behaviors in Americans at the community and national perspective.

Focuses on producer and director Donn Arden who's considered responsible for shaping the image of the Las Vegas show girl in the public's imagination and on Donn Arden paper collections. Biographical sketch of Arden; Details of photographs in the collection; Information on productions done by Arden; Documents of rehearsal schedules and costume lists; Efforts made to preserve the documents.

This note focuses on super‐priority liens (SPLs), which allow homeowner associations to foreclose a property over its mortgage. Twenty‐two states have so far implemented such liens, hoping to balance the interests of mortgage creditors and homeowner associations. The state of Nevada has been facing more challenges from both mortgage creditors and homeowner associations regarding the constitutionality of non‐judicial foreclosure than other states. This paper summaries the cases since 2000 and discusses the three major decisions that the Supreme Court of Nevada made involving SPLs' non‐judicial constitutionality, tender‐extinguishing SPLs, and federal creditors' role in SPLs. [ABSTRACT FROM AUTHOR]

This article presents information about research papers published in this issue of "The Journal of Social Issues." The research paper called "The Impact of Legalization on Illegal Gambling Participation," examines the effects of legalization on illegal gambling participation using a multivariate analysis to adjust for the influence of demographic variables. In addition, the incidence of illegal gambling in a nationwide sample was compared with the incidence reported by Nevada residents. Another research called "State Conducted Lotteries: History, Problems, and Promises," report that lotteries have played an important role in American finance through much of this Nation's history. This paper begins with an account of the abuses that led to the prohibition of the privately run lottery during the nineteenth century. It then goes on to analyze the promise and performance of the state run lotteries that have been created during the last decade. "The Changing Structure of American Gambling in the Twentieth Century," examines some of the factors that altered the economics and control of policy and numbers gambling, bookmaking, and casino gambling from 1900 to 1950.

Effects of climate change are likely to be detected in nearly all sectors and regions of the economy, with both winners and losers. One of the consequences of climatic changes could be altered regional water supplies. This paper presents an investigation of regional agricultural implications of changes in water availability. Specifically, using a profit maximization approach, the economic consequences of altered water availability in the Great Basin of Nevada are analyzed in terms of the effects on net returns of agricultural producers. Under the scenarios analyzed in this paper, it is found that with adequate water systems, increase in streamflow and consequent increase in water availability could significantly benefit agricultural producers of this region. Net returns to irrigators could increase by 8 to 13 percent, not taking into account the possibility of changes in crop yields and prices. It is also shown that the benefits from increased water availability are sensitive to likely crop yield and price changes. The potential for adverse effects of climatic changes on water supply is also considered by analyzing the effects of decreased water availability. Under decreased water availability scenarios, farmer net returns decrease substantially. [ABSTRACT FROM AUTHOR]

Presents an abstract of the study `Molecular Archaeology: An Analysis of Ancient Native American DNA from Western Nevada' by F.A. Kaestle.

The article offers information on several conventions related to systems research and behavioral science, including the 51st Annual Meeting of the International Society for the Systems Sciences to be held at Tokyo Institute of Technology in Japan from August 5 to 10, 2007, the 5th IIGSS Workshop to be held at Huazhong University of Science and Technology in China from June 14 to 17, and the ISOneWorld2007 Conference to be held in Las Vegas, Nevada from April 11 to 13.

As part of the site characterization efforts at Yucca Mountain, Nevada, a series of unsaturated zone tracer tests has been performed at nearby Busted Butte. The phase 2 tracer test was conducted within an instrumented 10 m by 10 m by 7 m in situ block of vitric tuff. A complex tracer solution containing both reactive and nonreactive tracers was pumped into the block during a period of 27 months. Throughout the test, thousands of unsaturated zone pore water samples were collected on sorptive pads attached to inverting membranes and then analyzed for tracer concentration. Partway through the experiment, three new boreholes were drilled into the block, and two intercepted the tracer plume. The rock core was removed for pore water extraction and analysis, and the boreholes were then instrumented with inverting membranes and sorptive pads. The initial set of pore water-soaked pads was removed from the boreholes a week after they were emplaced, and the pore water was extracted and analyzed. This paper compares the tracer concentration data from the rock cores and the pads to evaluate the effectiveness of the inverting membrane collection technique for a variety of tracers. While the sorptive pads sample only dissolved tracers, rock cores contain both dissolved and sorbed tracer. For nonreactive tracers, such as halides (bromide and iodide) and fluorinated benzoic acids (FBAs), this distinction is immaterial, and the rock and pad data agree quantitatively for the halide tracers, and qualitatively for the FBAs. For reactive tracers, such as lithium, the dissolved tracer concentrations can be estimated from rock analyses by dividing by the tracer's retardation factor; when this correction is applied, the rock and pad lithium data are also in reasonable agreement. [ABSTRACT FROM AUTHOR]

The Electric Power Research Institute (EPRI) has sponsored the development of a model to assess the long-term, overall 'performance' of the candidate spent fuel and high-level radioactive waste (HLW) disposal facility at Yucca Mountain, Nevada. The model simulates the processes that lead to HLW container corrosion, HLW mobilization from the spent fuel, and transport by groundwater, and contaminated groundwaterusage by future hypothetical individuals leading to radiation doses to those individuals. The model must incorporate a multitude of complex, coupled processes across a variety of technical disciplines. Furthermore, because of the very long time frames involved in the modeling effort (≫10^4 years), the relative lack of directly applicable data, and many uncertainties and variabilities in those data, a probabilistic approach to model development was necessary. The developers of the model chose a logic tree approach to represent uncertainties inboth conceptual models and model parameter values. The developers felt the logic tree approach was the most appropriate. This paper discusses the value and use of logic trees applied to assessing the uncertainties in HLW disposal, the components of the model, and a few of the results of that model. The paper concludes with a comparison of logic trees and Monte Carlo approaches. [ABSTRACT FROM AUTHOR]

This paper reports the results of a consensus conference of the Council of Emergency Medicine Residency Directors (CORD) to discuss the experiential training component of residency education in the emergency department (ED) and to make recommendations on structuring clinical training. Self-selected emergency medicine (EM) educators discussed experiential training focusing on three topic areas: 1) methods to optimize training in the clinical setting, 2) identification of goals and objectives by training year, and 3) determination of measurable behaviors demonstrating achievement of goals and objectives by residents. Topic areas were organized into the following questions: 1) what is the optimal number and evolution of ED shifts for EM residents during their residency training, 2) what clinical skills are expected of a resident at each level of training, and 3) what objective measures should be used to provide evidence of resident competency? Participants attended a lecture on the goals of the conference, the questions to be answered, and the role and implementation of deliberate practice into experiential training. Attendees were divided into three groups, each discussing one question. Each group had two discussion leaders. All discussions were digitally recorded for accuracy. After discussion all groups reconvened and reported summaries of discussions and recommendations to ensure group agreement. There were 59 participants representing 42 training programs. Educators agree that essential features of designing the ED clinical experience include the need to: 1) structure and tailor the clinical experience to optimize learning, 2) establish expectations for clinical performance based on year of training, and 3) provide feedback that is explicit to year-specific performance expectations. ACADEMIC EMERGENCY MEDICINE 2010; 17:S78-S86 © 2010 by the Society for Academic Emergency Medicine [ABSTRACT FROM AUTHOR]

Context: The challenge of providing meaningful health care services to veterans living in rural communities is a major public health concern that involves redefining the traditional facility-based model of care delivery employed in urban areas. Purpose: This paper describes the steps of a demonstration project, the Elko Telehealth Outreach Clinic. The clinic, located in Elko, Nevada, was created to meet the health care needs of veterans who expressed a desire for greater access to VA services. Methods: The Elko Telehealth Outreach Clinic is a specific example of the real-life implementation of the community-as-partner model as an operational framework for coordinating local, regional, and VA resources. The Elko Clinic provides a limited set of health care services including medication management, health education, prescription refills, routine lab tests, and specialty services through telehealth. Findings: From December 2006 to December 2007, a total of 84 unique veterans received health care services through the Elko Clinic. Conclusions: Our findings support the usefulness of an expanded community-as-partner model to guide a process for addressing the health care needs of veterans in Elko, Nevada, and they have implications for the development and maintenance of outreach clinics in other rural settings. [ABSTRACT FROM AUTHOR]

We used habitat-selection data from a reintroduced population of elk (Cervus elaphus) in northeastern Nevada, USA, to develop a resource- selection function to adjust nutritional carrying capacity estimates. Constrained estimates provide population levels that minimize overuse of key foraging communities. We estimated economic nutritional carrying capacity (INCC) for 236-kg lactating cow elk in autumn 1999 and 2000 to reflect expected animal performance under maintenance (2,550 kcal/kg DM) and good (2,750 kcal/kg DM) levels of standing digestible energy. We used our resource-selection function to redistribute INCC densities (RSFD) for aspen (Populus tremuloides), conifer, cud-leaf mountain mahogany (Cercocarpus Iedifolius), sagebrush (Artemisia spp.)-herb, and snowbrush ceanothus (Ceanothus velutinus) cover types across the summer range and then adjusted original `INCC estimates according to these RSFD when expected densities exceeded original INCC estimates. Maintenance performance INCC estimates were 2,533 cow elk (95% Cl: 1,327–3,739) in 1999 and 1,655 (95% Cl: 886–2,424) in 2000. Good performance INCC estimates were 2,264 cow elk (95% Cl: 1,150–3,378) in 1999 and 1,100 (95% Cl: 384–1,816) in 2000. The best habitat model provided evidence that forage availability and distance to water influenced habitat selection. Adjustments in INCC for 1999 and 2000 and at both performance levels corresponded to decreases of 18–35% in original INCC estimates. Decreases were attributed to more cow elk predicted by RSFD to be in aspen, conifer, and sagebrush-herb cover types than predicted by INCC. Each year, RSFD predicted that fewer elk would use mahogany and snowbrush cover types than original INCC models. The adjusted carrying capacity estimates provided population levels that should avoid appreciable alteration of aspen, conifer, and sagebrush-herb communities while ensuring nutritious resources during lean periods. Our paper provides a critical refinement for nutritional carrying capacity models through incorporating prediction of animal selection of nutritional resources. [ABSTRACT FROM AUTHOR]

A special capstone course for senior electrical and mechanical engineering students has been developed at the University of Nevada, Reno. The class also includes MBA students from the College of Business Administration. All phases of new product development including innovation, patent law, product liability, business, sales, marketing and venture capital are covered. This paper presents a brief description of the course and the assessment results. The assessment results indicate that the learning objectives are being met and that students strongly feel that invention and entrepreneurship should be part of the engineering curriculum. [ABSTRACT FROM AUTHOR]

We use the unique nature of the director and officer liability protection law applicable to Nevada incorporated firms to study how liability protection is related to corporate tax avoidance. We find that firms incorporated in Nevada avoid 32% more federal corporate tax as a fraction of total assets than firms incorporated in Delaware, and 40% more than firms incorporated in other states. Nevada‐incorporated firms have a 15% lower cash effective tax rate and an 8% lower GAAP ETR. The results are robust to various specifications including instrumental variable and matching approaches. Greater tax avoidance is also associated with lower payouts to shareholders for Nevada‐incorporated firms. The findings are consistent with theories about the complementarity of managerial diversion and tax avoidance for firms with poor monitoring, and they demonstrate how increases in liability protection lead to the unintended consequence of greater firm tax avoidance. [ABSTRACT FROM AUTHOR]

One of the major reasons for the reluctance to legalize many of the popular forms of gambling is the belief that these forms are particularly difficult to control honestly. It is generally believed that organized crime has been able to undermine regulatory mechanisms. This paper reports on the difficulties and successes of the Nevada Gambling Control Board's efforts to deal with a sophisticated and complex form of gambling organization and compares and contrasts that regulation with the regulation of casino gambling in England. [ABSTRACT FROM AUTHOR]

This paper examines the effects of legalization on illegal gambling participation using a multivariate analysis to adjust for the influence of demographic variables. In addition, the incidence of illegal gambling m a nationwide sample was compared with the incidence reported by Nevada residents. Games with similar structures and psychological characteristics appear to be complementary. That is, people who participate in one tend to participate in the other as well, regardless of their legal status. Dissimilar games operate as substitutes for each other. [ABSTRACT FROM AUTHOR]

Drought can affect both the quantity and quality of water in lakes and reservoirs, yet larger, highly managed waterbodies, such as Lake Mead, may be somewhat buffered from drought effects. From 2000 to present, Lake Mead has experienced a 71% decline in volume; however, influent water quality has remained high and consistent outflow volumes through Hoover Dam have been maintained. Furthermore, management activities, such as increased removal of phosphorus by wastewater dischargers and legacy contamination cleanup efforts, have been initiated since the drought began. These efforts have led to small improvements in values of water quality parameters, such as phosphorus, nitrogen, and perchlorate, despite loss of volume for dilution of constituents, and consequently, decreased residence time. As the drought continues, Lake Mead is projected to continue declining in volume, inflows are projected to become warmer, and the population of Las Vegas is projected to grow, potentially adding additional stress to the hydrologic system. Maintenance of outflow may mitigate some potentially negative consequences, and understanding the drivers behind continued high water quality despite prolonged drought is important to continue to maintain the health and vitality of the entire Lower Colorado River Basin. [ABSTRACT FROM AUTHOR]

This study investigates whether flipping activities impose an externality on the transaction prices of the neighboring nonflipped properties. Using a data set of residential property transactions in Clark County, Nevada for the period 2003–2013, we find that flippers impose a significant positive impact on the price of neighboring nonflipped properties in an up market, but a significant negative effect in a down market. This procyclical impact of flipping activity contributes to the volatility of housing prices, hence magnifying boom and bust cycles and increasing the likelihood of a mortgage crisis. [ABSTRACT FROM AUTHOR]

Mars' wet‐to‐dry transition is a major environmental catastrophe, yet the spatial pattern, tempo, and cause of drying are poorly constrained. We built a globally distributed database of constraints on Mars late‐stage paleolake size relative to catchment area (aridity index (AI)), and found evidence for climate zonation as Mars was drying out. Aridity increased over time in southern midlatitude highlands, where lakes became proportionally as small as in modern Nevada. Meanwhile, intermittently wetter climates persisted in equatorial and northern‐midlatitude lowlands. This is consistent with a change in Mars' greenhouse effect that left highlands too cold for liquid water except during a brief melt season, or alternatively with a fall in Mars' groundwater table. The data are consistent with a switch of unknown cause in the dependence of AI on elevation, from high‐and‐wet early on, to high‐and‐dry later. These results sharpen our view of Mars' climate as surface conditions became increasingly stressing for life. Plain Language Summary: Mars' surface was habitable in the past but is sterile today. Mars had multiple lake‐forming eras as the planet dried out, but so far, there has been no globally distributed survey of the size of late‐stage lakes, and the evaporation/precipitation ratio (aridity index (AI)) of the climates that formed them. This is key input/test data for models of Mars' past climate and climate evolution. We built a globally distributed database of AI constraints for late‐stage river‐forming climates on Mars. On average, late‐stage lake‐forming climates had a higher aridity than early‐stage river‐forming climates. Drying‐out was spatially heterogenous, with a "high‐and‐dry" pattern. This apparently contrasts with a "high‐and‐wet" pattern seen for early‐stage river‐forming climates. The reasons for this apparent switch are unknown. Key Points: Aridity on Mars increased over time, but intermittently wetter climates persisted in lowlandsConsistent with a change in Mars' greenhouse effect that left highlands too cold for liquid water except during a brief melt seasonData are consistent with switch, of unknown cause, in dependence of aridity index on elevation: high‐and‐wet early on, high‐and‐dry later [ABSTRACT FROM AUTHOR]

The North American Newark Canyon Formation (NCF; ∼113–98 Ma) presents an opportunity to examine how terrestrial carbonate facies reflect different aspects of paleoclimate during one of the hottest periods of Earth's history. The lower NCF type section preserves heterogeneous palustrine facies and the upper NCF preserves lacustrine deposits. We combined carbonate facies analysis with δ13C, δ18O, and Δ47 data sets to assess which carbonate facies preserve stable isotope signals that are most representative of climatic conditions. Palustrine facies record the heterogeneity of the original wetland environment in which they formed. Using the pelmicrite facies that formed in deeper wetlands, we interpret a lower temperature zone (35–40°C) to reflect warm season water temperatures. In contrast, a mottled micrite facies which formed in shallower wetlands records hotter temperatures (36–68°C). These hotter temperatures reflect radiatively heated "bare‐skin" temperatures that occurred in a shallow depositional setting. The lower lacustrine unit has been secondarily altered by hydrothermal fluids while the upper lacustrine unit likely preserves primary temperatures and δ18Owater of catchment‐integrated precipitation. Resultantly, the palustrine pelmicrite and lacustrine micrite are the facies most likely to reflect ambient climate conditions, and therefore, are the best facies to use for paleoclimate interpretations. Average warm season water temperatures of 41.1 ± 3.6°C and 37.8 ± 2.5°C are preserved by the palustrine pelmicrite (∼113–112 Ma) and lacustrine micrite (∼112–103 Ma), respectively. These data support previous interpretations of the mid‐Cretaceous as a hothouse climate and demonstrate the importance of characterizing facies for identifying the data most representative of past climates. Plain Language Summary: Considered a "supergreenhouse" world, the Cretaceous (145–65 Mya) was one of the hottest periods in geologic history. Understanding how environments respond to extreme global warmth provides insights that will help to mitigate the harmful effects of modern climate change. Geochemical signals, like stable isotopes, preserved in rocks allow us to reconstruct past climate conditions. We use stable isotope geochemistry on limestones (rocks made of carbonate minerals) to estimate average mid‐Cretaceous (∼110 Mya) summer temperatures in Nevada, USA. We examine limestones that formed in wetlands and lakes to assess which types record signals representative of the original landscape and which have values that were altered after the rock formed. We find that carbonates deposited in the shallowest parts of wetland environments record temperatures much hotter than air or deeper water temperatures due to extreme land surface heating, while deeper wetland limestones preserve temperatures more representative of ambient conditions. Average warm season water temperatures for wetland and lake carbonates are approximately 41 and 38°C, respectively, revealing hot conditions that support our understanding of the Cretaceous as a greenhouse world. This research provides an example of how to interpret useful climate information from complex carbonate data sets. Key Points: Deeper palustrine and unaltered lacustrine carbonates record warm season water temperatures of approximately 41 and 38°C, respectivelyHigh temperatures from well‐preserved shallower palustrine carbonates likely reflect radiative heatingCareful facies analysis is imperative for robust paleoclimate interpretation of heterogeneous terrestrial carbonate archives [ABSTRACT FROM AUTHOR]

We investigate postseismic deformation following the 15 May 2020, Mw 6.5 Monte Cristo Range, Nevada earthquake using geodetic and aftershock data. Seven months of Sentinel 1‐A/B SAR images were used to model deformation as afterslip on two subparallel fault planes outlined by aftershocks. Postseismic deformation fits exponential and logarithmic decay models equally well. For exponential decay, the average decay time is ∼38 days. On the western plane, where most coseismic slip was observed, afterslip was minor, occurred at shallower depths than coseismic slip, and is anticorrelated with aftershock distribution. On the eastern plane, afterslip is significant, exceeds coseismic moment release, occurred at and below coseismic slip, and is correlated with aftershock distribution. On both segments, geodetic moment exceeds seismic moment, suggesting most afterslip occurred aseismically. Aseismic creep does not make up for observed coseismic shallow slip deficit, perhaps related to fault immaturity. Plain Language Summary: Monitoring surface deformation and slip at depth after an earthquake can be used to investigate changes in the local stress field caused by earthquakes and infer frictional and other conditions on earthquake‐causing faults. We used InSAR satellite data and ground‐based seismic data to study afterslip associated with a moderate magnitude earthquake in Nevada that occurred on 15 May 2020. Most energy after the mainshock was released aseismically rather than as aftershocks. The large (∼1.4 m) coseismic slip that occurred at a depth of about 8–10 km never propagated to the surface, either during or after the earthquake. Geologic estimates of motion on this fault would therefore underestimate the motion at depth, perhaps leading to underestimation of the fault's long‐term slip rate. Key Points: InSAR time series reveal that the average characteristic relaxation time for postseismic motion is ∼38 days for the Monte Cristo Range earthquakeWhile aseismic afterslip exceeded seismic afterslip, combined afterslip did not compensate for the shallow coseismic slip deficitFault immaturity might explain the shallow slip deficit and the relatively low amount of afterslip compared to coseismic slip [ABSTRACT FROM AUTHOR]

Non‐native ungulate grazing has negatively impacted native species across the globe, leading to massive loss of biodiversity and ecosystem services. Despite their pervasiveness, interactions between non‐native grazers and native species are not fully understood. We often observe declines in demography or survival of these native species, but lack understanding about the mechanisms underlying these declines. Physiological stress represents one mechanism of (mal)adaptation, but data are sparse. We investigated glucocorticoid levels in a native avian herbivore exposed to different intensities of non‐native grazing in the cold desert Great Basin ecosystem, USA. We measured corticosterone, a glucocorticoid in feathers for a large sample (n = 280) of female greater sage‐grouse (Centrocercus urophasianus) from three study areas in Northern Nevada and Southern Oregon with different grazing regimes of livestock and feral horses. We found that greater feral horse density was associated with higher corticosterone levels, and this effect was exacerbated by drought conditions. Livestock grazing produced similar results; however, there was more model uncertainty about the livestock effect. Subsequent nesting success was lower with increased feather corticosterone, but corticosterone levels were not predictive of other vital rates. Our results indicate a physiological response by sage‐grouse to grazing pressure from non‐native grazers. We found substantial among‐individual variation in the strength of the response. These adverse effects were intensified during unfavorable weather events, highlighting the need to reevaluate management strategies in the face of climate change. [ABSTRACT FROM AUTHOR]

We present a shallow, isothermal, Newtonian model for the transient interaction of lava flows with topography. Numerical integrations and simple mathematical approximations are deployed to quantify how topography controls lava thicknesses and flow speeds. Considering idealized topographic features, we show that modest depressions thicken and accelerate the flow—even far downstream—whilst mounds have the opposite effect. However, deep ponds of lava form in depressions of sufficient amplitude, which introduces a long timescale for lava to fill the depression and hence the accelerated downstream flow may never be attained. Relatively large mounds completely divert the lava, providing protected lava‐free regions for homes and infrastructure. There can, however, be hazardous, deep, fast flow around the edges of the mound, owing to diversion. Additionally, we show that our model accurately predicts the lava‐free region that has been observed in the eruption 35 kyr ago at Marcath Volcano, Nevada. Plain Language Summary: Lava flows in volcanic regions cause huge amounts of economic damage. We develop a model to predict the depth and speed of lava flows over uneven surfaces, aiming to locate safe regions in which homes and infrastructure are protected from the flow. We show that mounds both thin and slow the flow of lava over them, with lava‐free safe regions forming downslope of larger mounds. Depressions have the opposite effect, thickening and accelerating the lava flow. Lava ponds within deep depressions, which can delay the progress of the flow, giving occupants of the area longer to evacuate, and potentially protecting them for the entire duration of an eruption. Additionally, we apply our model to a real scenario, showing that it reproduces the lava‐free region that has been observed at Marcath Volcano, Nevada. Key Points: Safe regions, into which lava does not flow, form downslope of sufficiently elevated features. Fast, deep flow is diverted to their marginsLava ponds in deep depressions. Flow is delayed by the time taken to fill the depression. The region downstream stays lava‐free for longerOur model is compared to the lava field at Marcath Volcano and replicates an observed lava‐free region downslope of a topographic high [ABSTRACT FROM AUTHOR]

Quartz‐in‐garnet elastic geobarometry (QuiG) pressures in rocks from two Barrovian metamorphic terranes in the western US Cordilleran hinterland exceed pressures determined using chemical thermodynamics by 3–4 kbar. For this study, 135 quartz inclusions from the Funeral Mountains, California, were analysed using QuiG in five garnets from three locations representing metamorphic grades of upper greenschist, lower amphibolite, and middle amphibolite facies. From a second Barrovian terrane, the Wood Hills in northeastern Nevada, 125 quartz inclusions were analysed using QuiG in 14 garnets from a single rock sample metamorphosed to middle amphibolite facies. Pressures determined for rocks in the Funeral Mountains using QuiG and methods rooted in equilibrium thermodynamics yielded consistent pressure differences between locations, but QuiG pressures are higher. Similarly, QuiG pressures determined for rocks in the Wood Hills are higher than pressures determined by equilibrium thermodynamic approaches. Possible explanations for the pressure differences include garnet compositions not reflecting equilibrium, sources of error in thermodynamic calculations such as thermodynamic data or a‐X models, or an unknown source of systematic error that causes QuiG to overestimate pressures of entrapment. To test Raman spectroscopy's ability to reproduce inclusion pressures, pressures were calculated using Raman spectroscopy and synchrotron X‐ray diffraction, which yielded consistent pressures and support the use of the single mode‐shift of the 464 cm−1 band of quartz for geobarometry, which simplifies the method by assuming hydrostatic compression of quartz. These results are compared with pressures obtained using Grüneisen tensors and show consistency between these different approaches. [ABSTRACT FROM AUTHOR]

In North America, Mexican free‐tailed bats (Tadarida brasiliensis mexicana) consume vast numbers of insects contributing to the economic well‐being of society. Mexican free‐tailed bats have declined due to historic guano mining, roost destruction, and bioaccumulation of organochlorine pesticides. Long‐distance migrations and dense congregations at roosts exacerbate these declines. Wind energy development further threatens bat communities worldwide and presents emerging challenges to bat conservation. Effective mitigation of bat mortality at wind energy facilities requires baseline data on the biology of affected populations. We collected data on age, sex, and reproductive condition of Mexican free‐tailed bats at a cave roost in eastern Nevada located 6 km from a 152‐MW industrial wind energy facility. Over 5 years, we captured 46,353 Mexican free‐tailed bats. Although just over half of the caught individuals were nonreproductive adult males (53.6%), 826 pregnant, 892 lactating, 10,101 post‐lactating, and 4327 nonreproductive adult females were captured. Juveniles comprised 11.5% of captures. Female reproductive phenology was delayed relative to conspecific roosts at lower latitudes, likely due to cooler temperatures. Roost use by reproductive females and juvenile bats demonstrates this site is a maternity roost, with significant ecological and conservation value. To our knowledge, no other industrial scale wind energy facilities exist in such proximity to a heavily used bat roost in North America. Given the susceptibility of Mexican free‐tailed bats to wind turbine mortality and the proximity of this roost to a wind energy facility, these data provide a foundation from which differential impacts on demographic groups can be assessed. [ABSTRACT FROM AUTHOR]

The Colorado River Basin is a hydrologic river network that directs runoff from rain and snow falling on mountains, primarily in Colorado and Wyoming, to the Colorado River Delta in Mexico. Over the last century, in response to basin‐wide water shortages, legal agreements between stakeholders in seven U.S. states and Mexico, hydrologic flows from users on the main stem of the river have been reallocated to junior water rights holders. Municipalities, businesses, farmers, and households utilize the Colorado River water to produce and trade valuable, water‐derived goods and services, which effectively reallocates water through a continually adapting, boundary‐free economic river network providing indirect access to "virtual" Colorado River water. We conceptualize the Colorado River Basin as a multiplex network comprised of interdependent natural flow networks, direct (infrastructural) flow networks, and indirect (virtual) flow networks. Using this reframing, we quantify the total hydrosocial impact of the Drought Contingency Plan (DCP) on Lower Basin states. For each Mm3 of water reduced through the DCP, Arizona, Nevada, and California lose an additional 0.42–0.43 Mm3, 0.33–0.51 Mm3, and 1.06–1.10 Mm3 of virtual water flow, respectively. Hence, the DCP will require Arizona, Nevada, and Southern California to restructure how they use water, relying less on direct and indirect consumption of the Colorado River water and finding more indirect water sources outside that basin. [ABSTRACT FROM AUTHOR]

We compare various methods for resolving steady flow within three‐dimensional discrete fracture networks, including direct methods, Krylov subspace methods with and without preconditioning, and multi‐grid methods. We compared the performance of the methods based on compute times and scaling of the solution as a function of the number of grid nodes and log‐variance of the hydraulic aperture. The methods are applied to three test cases: (a) variable density of networks with a truncated power‐law distribution of fracture lengths, (b) a fixed network composed of monodisperse fracture sizes but varied permeability/aperture heterogeneity, (c) and a network based on field site in Nevada, US. We chose these cases to allow us to study the impact of the mesh size and flow properties, as well as to demonstrate our conclusions on a large‐scale, realistic problem (more than 40 million mesh nodes). A direct solution using Cholesky factorization outperformed other methods for every example but was closely followed in performance by some algebraic multigrid (AMG) preconditioned Krylov subspace methods. Among the Krylov methods, conjugate gradients (CG) with an AMG preconditioner performs the best. Generally, Cholesky factorization is recommended, but CG with an AMG preconditioner may be suitable for very large problems beyond 40 million nodes where the entire linear system cannot reside in memory. Key Points: Cholesky factorization generally outperforms alternative methods for solving flow equations in discrete fracture networksThe conjugate gradient method combined with an algebraic multigrid (AMG) preconditioner performs the best among iterative methodsThe conjugate gradient method with an AMG preconditioner competes with Cholesky factorization for huge fracture networks [ABSTRACT FROM AUTHOR]

As an evaluation method, standardized patients have a long history in medical education and research yet are less established in nursing. This paper explores the reliability of using standardized patients as the evaluative method in a communication competence pilot study with international nurses. Standardized patients and second raters scored the same encounters. We examined the scores by intraclass correlation coefficients. Anecdotal comments by the two types of raters were assessed qualitatively to highlight similarities and areas of difference between them. The results of reliability analysis for standardized patients scores for the composite variables of Establishing Communicative Rapport, Therapeutic Communication, Non-Verbal Communication, and Overall Satisfaction ranged from 0.755 ( P < 0.01) to 0.42 ( P = 0.09). In this study, the results showed standardized patient evaluation has moderate to substantial reliability when compared to second raters of the same set of clinical encounters. This is similar to the reliability established over many decades of medical research. Greater use of this dynamic and interactive technique may be beneficial to nursing education and research. [ABSTRACT FROM AUTHOR]

Devils Hole is a collapse depression connected to the regional carbonate aquifer of the Death Valley ground water flow system. Devils Hole pool is home to an endangered pup-fish that was threatened when irrigation pumping in nearby Ash Meadows lowered the pool stage in the 1960s. Pumping at Ash Meadows ultimately ceased, and the stage recovered until 1988, when it began to decline, a trend that continued until at least 2004. Regional ground water pumping and changes in recharge are considered the principal potential stresses causing long term stage changes. A regression was found between pumpage and Devils Hole water levels. Though precipitation in distant mountain ranges is the source of recharge to the flow system, the stage of Devils Hole shows small change in stage from 1937 to1963, a period during which ground water withdrawals were small and the major stress on stage would have been recharge. Multiple regression analyses, made by including the cumulative departure from normal precipitation with pumpage as independent variables, did not improve the regression. Drawdown at Devils Hole was calculated by the Theis Equation for nearby pumping centers to incorporate time delay and drawdown attenuation. The Theis drawdowns were used as surrogates for pumpage in multiple regression analyses. The model coefficient for the regression, R² = 0.982, indicated that changes in Devils Hole were largely due to effects of pumping at Ash Meadows, Amargosa Desert, and Army 1. [ABSTRACT FROM AUTHOR]

We present new P and S teleseismic tomography models of the upper mantle beneath California and Nevada. Improved tomographic methods and the incorporation of new data increase image resolution and seismic structure definition. Technical advancements include the use of 3‐D ray tracing, ray weighting and finite‐frequency sensitivity kernels. Together with the incorporation of modern crustal velocity models to account for crustal delay time, these tomographic advancements reveal slightly higher amplitudes and narrower structures beneath prominent tectonic features in California and Nevada. The addition of new data from the southern California Borderland and northwestern California are particularly useful. Based on our imaging results, we discuss the effects of temperature and partial melt on upper mantle seismic velocity beneath California and Nevada. We interpret the major seismically fast structures in our study area to be Juan de Fuca slab and its downward continuation beneath central Nevada and foundered Farallon lithosphere beneath the southern Sierra Nevada and Transverse Ranges. The seismically slow structures beneath the slab‐free window of northern California Coast Range, the Salton Trough extensional basin, and the Cascadia back arc, are all consistent with the presence of partial melting of decompressing mantle. The imaged seismically fast and slow anomalies imply buoyancy variations and melt productivity that ultimately act on the overlying crust. Plain Language Summary: We present new images of the structure of the upper mantle beneath California and Nevada based on the travel times of seismic waves from around the world. Modern methods and new data increase image resolution and seismic structure definition, and these advancements reveal stronger and narrower structures beneath prominent geologic features in California and Nevada. Based on our results we discuss the effects of temperature and partial melt on upper mantle seismic velocity beneath this region. We interpret structures in the upper mantle beneath central Nevada, the southern Sierra Nevada, the Transverse Ranges, and the Salton Trough. The imaged regions of faster seismic wave speeds are associated primarily with the Juan de Fuca‐Farallon slab. Structures imaged with slower seismic wave speeds indicate the presence of partial melt in the upper mantle. These seismic anomalies imply variations in the upper mantle that ultimately impact the overlying crust in California and Nevada. Key Points: We image upper mantle structures beneath California and Nevada with improved seismic techniques and an expanded data setThe major seismically fast anomalies likely represent fragments of Farallon oceanic lithosphereSlow anomalies are consistent with elevated temperatures and partial melt of decompressing mantle [ABSTRACT FROM AUTHOR]

We present a data‐driven approach to clustering or grouping Global Navigation Satellite System (GNSS) stations according to observed velocities, displacements or other selected characteristics. Clustering GNSS stations provides useful scientific information, and is a necessary initial step in other analysis, such as detecting aseismic transient signals (Granat et al., 2013, https://doi.org/10.1785/0220130039). Desired features of the data can be selected for clustering, including some subset of displacement or velocity components, uncertainty estimates, station location, and other relevant information. Based on those selections, the clustering procedure autonomously groups the GNSS stations according to a selected clustering method. We have implemented this approach as a Python application, allowing us to draw upon the full range of open source clustering methods available in Python's scikit‐learn package (Pedregosa et al., 2011, https://doi.org/10.5555/1953048.2078195). The application returns the stations labeled by group as a table and color coded KML file and is designed to work with the GNSS information available from GeoGateway (Donnellan et al., 2021, https://doi.org/10.1007/s12145-020-00561-7; Heflin et al., 2020, https://doi.org/10.1029/2019ea000644) but is easily extensible. We demonstrate the methodology on California and western Nevada. The results show partitions that follow faults or geologic boundaries, including for recent large earthquakes and post‐seismic motion. The San Andreas fault system is most prominent, reflecting Pacific‐North American plate boundary motion. Deformation reflected as class boundaries is distributed north and south of the central California creeping section. For most models a cluster boundary connects the southernmost San Andreas fault with the Eastern California Shear Zone (ECSZ) rather than continuing through the San Gorgonio Pass. Key Points: Unsupervised clustering methods provide a data‐driven way of analyzing and partitioning Global Navigation Satellite System observations of crustal deformationDeformation is distributed across the San Andreas fault system but is localized at the creeping section in central CaliforniaThe Southern San Andreas fault connects with the Eastern California Shear Zone rather than the rest of the San Andreas fault system [ABSTRACT FROM AUTHOR]

Uncertainty quantification of groundwater (GW) aquifer parameters is critical for efficient management and sustainable extraction of GW resources. These uncertainties are introduced by the data, model, and prior information on the parameters. Here, we develop a Bayesian inversion framework that uses Interferometric Synthetic Aperture Radar (InSAR) surface deformation data to infer the laterally heterogeneous permeability of a transient linear poroelastic model of a confined GW aquifer. The Bayesian solution of this inverse problem takes the form of a posterior probability density of the permeability. Exploring this posterior using classical Markov chain Monte Carlo (MCMC) methods is computationally prohibitive due to the large dimension of the discretized permeability field and the expense of solving the poroelastic forward problem. However, in many partial differential equation (PDE)‐based Bayesian inversion problems, the data are only informative in a few directions in parameter space. For the poroelasticity problem, we prove this property theoretically for a one‐dimensional problem and demonstrate it numerically for a three‐dimensional aquifer model. We design a generalized preconditioned Crank‐Nicolson (gpCN) MCMC method that exploits this intrinsic low dimensionality by using a low‐rank‐based Laplace approximation of the posterior as a proposal, which we build scalably. The feasibility of our approach is demonstrated through a real GW aquifer test in Nevada. The inherently two‐dimensional nature of InSAR surface deformation data informs a sufficient number of modes of the permeability field to allow detection of major structures within the aquifer, significantly reducing the uncertainty in the pressure and the displacement quantities of interest. Key Points: Using Interferometric Synthetic Aperture Radar data reduces the uncertainty in selected quantities of interest compared to using prior knowledge onlyThe preconditioned Crank‐Nicolson (pCN) Markov chain Monte Carlo (MCMC) method is extended to exploit posterior curvature and allow better chain mixingWe demonstrate the intrinsic low dimensionality of the poroelastic inverse problem that is, critical for the success of the MCMC method [ABSTRACT FROM AUTHOR]

Eocene strata of the Elko Formation record lacustrine deposition within the Nevada hinterland of the North American Cordillera. We present a detailed geochemical stratigraphy enabled by high‐sampling‐resolution geochronology from lacus trine limestone and interbedded volcanic rocks of the Elko Formation. Two intervals of lacustrine deposition, an early Eocene "Lake Adobe" of limited aerial extent and a laterally extensive middle Eocene "Lake Elko," are separated by ∼5 m.y. of apparent unconformity. Sediments deposited in the apparently short‐lived (49.5–48.5 Ma) early Eocene Lake Adobe exhibit high‐amplitude covariation of δ18O, δ13C and 87Sr/86Sr, which suggests a dynamically changing catchment and precipitation regime. Lake Elko formed during the middle Eocene, and its strata record three geochemically distinct phases, indicating it was a single interconnected water body that became increasingly evaporative over time. The lower Elko Formation (44.0–42.5 Ma) was deposited in a freshwater lake. Middle Elko Formation (42.5–41.2 Ma) lithofacies and geochemistry suggest that an increasingly saline and alkaline Lake Elko experienced salinity stratification‐induced hypolimnion disoxia and burial of 12C‐rich organic matter. The upper Elko Formation (41.2–40.5 Ma) records a shallow final phase of Lake Elko that experienced short residence times and a breakdown in stratification. A sharp decline of 87Sr/86Sr in the upper Elko Formation reflects an increasing aerial extent of low‐87Sr/86Sr volcanic deposits from nearby calderas. Middle Eocene strata record ponding of paleodrainage, increasing hydrologic isolation and volcanism, consistent with progressive north to south removal of the Farallon flat slab and/or delamination of the lower lithospheric mantle of the North American plate. Plain Language Summary: Large lakes formed in the region that is now northeast Nevada between 50 and 40 million years ago. This region was at high elevation and undergoing a transition from compressional to extensional plate tectonic forces at that time. The geologic record shows that lakes formation started locally at 49.5 million years ago with a short‐lived freshwater Lake Adobe. Later, approximately 43.5 million years ago, a broad Lake Elko formed and then became increasingly evaporative over the next 3 million years, likely due to removal of the shallowly subducting Farallon slab from beneath the region. Key Points: Lakes formed in the hinterland of the North American Cordillera during the Eocene during a transition from contraction to extensionLake Elko expanded and became increasingly evaporative across 3.5 Ma from 43.5–40.5 Ma, coincident with an episode of explosive siliceous magmatismLake formation and drainage isolation likely records the progressive removal of the flattened Farallon slab from beneath the Cordillera [ABSTRACT FROM AUTHOR]

Presents a study which reevaluated the natural ground water discharge from Las Vegas Valley (LVV) in Nevada prior to urbanization. Hydrologic history of LVV; Plant response to water availability; Water use estimates for plant communities in LVV in 1905.

Forensic pathologists' decisions are critical in police investigations and court proceedings as they determine whether an unnatural death of a young child was an accident or homicide. Does cognitive bias affect forensic pathologists' decision‐making? To address this question, we examined all death certificates issued during a 10‐year period in the State of Nevada in the United States for children under the age of six. We also conducted an experiment with 133 forensic pathologists in which we tested whether knowledge of irrelevant non‐medical information that should have no bearing on forensic pathologists' decisions influenced their manner of death determinations. The dataset of death certificates indicated that forensic pathologists were more likely to rule "homicide" rather than "accident" for deaths of Black children relative to White children. This may arise because the base‐rate expectation creates an a priori cognitive bias to rule that Black children died as a result of homicide, which then perpetuates itself. Corroborating this explanation, the experimental data with the 133 forensic pathologists exhibited biased decisions when given identical medical information but different irrelevant non‐medical information about the race of the child and who was the caregiver who brought them to the hospital. These findings together demonstrate how extraneous information can result in cognitive bias in forensic pathology decision‐making. [ABSTRACT FROM AUTHOR]

Aftershock cascades play an important role in forecasting seismicity in natural and human‐made situations. While their behavior including the spatial aftershock zone has been the focus of many studies in tectonic settings, this is not the case when fluid flows are involved. Using high‐quality seismic catalogs, we probe aftershocks dynamics in five settings influenced by fluids: (a) induced seismicity in Oklahoma and Kansas, (b) natural swarms in California and Nevada, and (c) suspected swarms in the Yuha Desert (California). All settings exhibit significant aftershock behavior highlighting the importance of event‐event triggering processes. The spatial aftershock zones scale with mainshock magnitude as expected based on the rupture length. While (a) and (b) show a rapid decay beyond their rupture length, (c) exhibits long‐range behavior suggesting that fluid migration might not be the dominant mechanism. We also find that the scaling of aftershock productivity with mainshock magnitude together with the Gutenberg‐Richter b‐value might allow to distinguish between natural swarms and induced seismicity. Plain Language Summary: While it is known that fluid injection operations can induce seismic activity, it has remained unclear how this activity compares to their natural counterpart, seismic swarms driven by natural fluid flows. The latter are typically characterized by the absence of a dominant event within the seismic sequence, while exhibiting other characteristics consistent with tectonic sequences including aftershock triggering. Our analysis of high‐quality seismic catalogs for both types of fluid‐driven seismicity shows that both exhibit a significant amount of aftershocks arising from "secondary" processes (i.e. stress‐based event‐event triggering as an indirect consequence of fluid injections) leading to spatially localized aftershocks zones. Yet, the trade‐off between the seismic productivity relation, which refers to the average increase in the number of aftershocks with the magnitude of their trigger, and the distribution of earthquake magnitudes controls the relative role of small compared to large triggers and we find that aftershock triggering is much more dominated by smaller events in the induced setting. Both findings are of direct importance for earthquake forecasting and seismic hazard assessment. Key Points: Significant event‐event triggering is present in both natural swarms and induced seismicityBoth fluid‐driven settings are characterized by narrow aftershock zonesAftershock triggering is dominated by smaller triggers in induced seismicity but much less so for natural swarms [ABSTRACT FROM AUTHOR]

Background: Remission of diabetes can be rewarding for patients and physicians, but there is limited study of how patients perceive the timeline of a disease along the continuum of glycaemic control. Objective: To explore how patients perceive the timeline of diabetes along the continuum of glycaemic control and their goals of care and to identify whether family physicians communicate the principles of regression and remission of diabetes. Design: Mixed methods approach of qualitative semi‐structured interviews with purposive sampling followed by cross‐sectional survey of physicians. Participants: Thirty‐three patients living with prediabetes (preDM) or type 2 diabetes mellitus (T2DM) at medical centres in Georgia and Nevada; and 387 family physicians providing primary care within the same health system. Results: Patients described two timelines of diabetes: as a lifelong condition or as a condition that can be cured. Patients who perceived a lifelong condition described five treatment goals: reducing glucose‐related laboratory values, losing weight, reducing medication, preventing treatment intensification and avoiding complications. For patients who perceived diabetes as a disease with an end, the goal of care was to achieve normoglycaemia. In response to patient vignettes that described potential cases of remission and regression, 38.2% of physician respondents would still communicate that a patient has preDM and 94.6% would tell the patient that he still had diabetes. Conclusions: Most physicians here exhibited reluctance to communicate remission or regression in patient care. Yet, patients describe two different potential timelines, including a subset who expect their diabetes can be 'cured'. Physicians should incorporate shared decision making to create a shared mental model of diabetes and its potential outcomes with patients. Patient or Public Contribution: In this mixed methods study, as patients participated in the qualitative phase of this study, we asked patients to tell us what additional questions we should ask in subsequent interviews. Data from this qualitative phase informed the design and interpretation of the quantitative phase with physician participants. [ABSTRACT FROM AUTHOR]

Perennially and intermittently available water in lentic, spring‐fed herbaceous meadows supports wetland plants that build and maintain absorbent soil organic matter, capture sediment, prevent erosion, and thereby sustain riparian ecosystems. Enhanced forage and available water attract a diversity of wildlife and grazing animals that can degrade riparian vegetation through prolonged overuse. We tested novel monitoring methods and adapted existing methods to obtain quantified vegetation data that have been consistently linked to riparian functionality and compared these data to ungulate species use. We quantified ungulate use with time‐lapse cameras at 10 Nevada spring‐fed herbaceous meadows where core greater sage‐grouse (Centrocercus urophasianus) habitat, public land grazing allotments, and free‐roaming horse (Equus caballus) herd management areas (Bureau of Land Management) or territories (U.S. Department of Agriculture Forest Service) overlapped. Free‐roaming horses used most study sites over longer periods and grazed more intensely than cattle or domestic sheep. Native ungulate grazing intensity was comparatively negligible. Free‐roaming horses selected spring‐fed meadow sites on average 51 (±33 [SE]) times more than the surrounding rangelands, and cattle selected them 30 ± 23 times more. Within the wettest area of a site, study sites with longer duration of use and higher intensity of use had more soil alteration and bare ground. Riparian ecosystem degradation occurred where meadows had limited rest or recovery time from grazing during the growing season. At all sites we noted loss of riparian function, especially within the hydric areas with the highest potential to grow abundant cover of stabilizing wetland plant species. Transects for monitoring soil alteration and vegetation cover in this hydric location can provide a leading indicator of riparian recovery or degradation and help in adjusting free‐roaming horse population levels or livestock management strategies. © 2021 The Wildlife Society. : Horse and cattle grazing throughout the grazing season impaired functioning of spring‐fed herbaceous meadows across Nevada, USA. The wettest portion of the meadow provided a clear signal we could relate to animal use and wetland function. [ABSTRACT FROM AUTHOR]

Applying models to developed agricultural regions remains a difficult problem because there are no existing modeling codes that represent both the complex physics of the hydrology and anthropogenic manipulations to water distribution and consumption. We apply an integrated groundwater – surface water and hydrologic river operations model to an irrigated river valley in northwestern Nevada/northern California, United States to evaluate the impacts of climate change on snow‐fed agricultural systems that use surface water and groundwater conjunctively. We explicitly represent individual surface water rights within the hydrologic model and allow the integrated code to change river diversions in response to earlier snowmelt runoff and water availability. Historically under‐used supplemental groundwater rights are dynamically activated within the model to offset diminished surface water deliveries. The model accounts for feedbacks between the natural hydrology and anthropogenic stresses, which is a first‐of‐its‐kind assessment of the impacts of climate change on individual water rights, and more broadly on river basin operations. Earlier snowmelt decreases annual surface water deliveries to all water rights, not just the junior water rights, owing to a lack of surface water storage in the upper river basin capable of capturing earlier runoff. Conversely, downstream irrigators with access to reservoir storage benefit from earlier runoff flowing past upstream points of diversion prior to the start of the irrigation season. Despite regional shifts toward greater reliance on groundwater for irrigation, crop consumption (a common surrogate for crop yield) decreases due to spatiotemporal changes in water supply that preferentially impact a subset of growers in the region. Plain Language Summary: Warming temperatures associated with climate change will result in earlier snowmelt. This will impact agricultural systems that depend on snowmelt‐derived surface water for irrigation. We present a model that dynamically links water use as dictated by prior appropriations water law (i.e., priority based on first date of beneficial use) with groundwater use to augment surface water shortfalls (i.e., "conjunctive groundwater use"). Simulations of water availability and water use patterns in a complex conjunctive‐use agricultural basin fed by snowmelt are evaluated for a 35‐year simulation period subjected to incremental atmospheric warming of 1°–5°C. Key Points: Fully integrated river operations and hydrology model that explicitly represents individual water rights within the modeled basin and increases groundwater pumping for irrigation during shortfalls in surface water is applied to an agricultural basinLate‐century climate change associated with earlier snowmelt reduces surface water supply during the irrigation season leading to increased groundwater pumping for agriculture to offset surface water irrigation shortfalls and hence impacts groundwater resourcesEarlier snowmelt/runoff associated with predicted climate warming reduces surface water availability to all prior appropriation water rights (not just "senior" rights) during the irrigation season in upstream sub‐basins and boosts surface water flows to downstream sub‐basins during the non‐irrigation season [ABSTRACT FROM AUTHOR]

The recovery of freshly fallen meteorites from tracked and triangulated meteors is critical to determining their source asteroid families. Even though our ability to locate meteorite falls continues to improve, the recovery of meteorites remains a challenge due to large search areas with terrain and vegetation obscuration. To improve the efficiency of meteorite recovery, we have tested the hypothesis that meteorites can be located using machine learning techniques and an autonomous drone. To locate meteorites autonomously, a quadcopter drone first conducts a grid survey acquiring top‐down images of the strewn field from a low altitude. The drone‐acquired images are then analyzed using a machine learning classifier to identify meteorite candidates for follow‐up examination. Here, we describe a proof‐of‐concept meteorite classifier that deploys off‐line a combination of different convolution neural networks to recognize meteorites from images taken by drones in the field. The system was implemented in a conceptual drone setup and tested in the suspected strewn field of a recent meteorite fall near Walker Lake, Nevada. [ABSTRACT FROM AUTHOR]

This paper examines several dimensions of public opposition to the proposed siting of the high-level nuclear waste repository at Yucca Mountain. In order to provide a context for the public's view of the repository in metropolitan Clark County, both governmental studies of the repository siting process are analyzed, as well as elements of the Nuclear Waste Policy Act. This analysis suggests that one potentially key component of the public's opposition to the siting, as well as their perceptions of risk of the facility, may be the result of a lack of trust in the Department of Energy. Empirical analysis of survey data collected in Nevada in 1988 confirms the strong relationship between political trust and repository risk perceptions. [ABSTRACT FROM AUTHOR]

This paper examines the possibility of criticality in a nuclear waste repository. The estimated probabilities are rough bounds and do notentirely dismiss the possibility of a critical condition; however, they do point to the difficulty of creating conditions under which a critical mass could be assembled (i.e., corrosion of containers, separation of neutron absorbers from the fissile material and collapse or precipitation of the fissile material). In addition, should a criticality occur in or near a container, the bounding consequence calculations showed that fissions from one critical event are quite small (< ~1020 fissions, if similar to aqueous and metal accidents and experiments). Furthermore, a reasonable upper bound of total critical events of 1028 fissions corresponds to only 0.1% of the number of fissions represented by the spent nuclear fuel inventory in a repository containing 70,000 metric tons of heavy metal (MTHM) (the expected size for the proposed repository at Yucca Mountain, Nevada. [ABSTRACT FROM AUTHOR]

No public policy issue has been as difficult as high-level nuclear waste. Debates continue regarding Yucca Mountain as a disposal site, and -- more generally -- the appropriateness of geologic disposal and the need to act quickly. Previous research has focused on possible social, political, and economic consequences of a facility in Nevada. Impacts have been predicted to be potentially large and to emanate mainly from stigmatization of the region due to increased perceptions of risk. Analogous impacts from leaving waste at power plants have been either ignored or assumed to be negligible. This paper presents survey results on attitudes of residents in three counties where nuclear waste is currently stored. Topics include perceived risk, knowledge of nuclear waste and radiation, and impacts on jobs, tourism, and housing values from leaving waste on site. Results are similar to what has been reported for Nevada; the public is concerned about possible adverse effects from on-site storage of waste. [ABSTRACT FROM AUTHOR]

In an effort to determine contaminant presence, concentrations, and movement from a low‐level radioactive waste (LLRW) burial disposal site to ecosystems in the surrounding area, a study was developed to assess concentrations of per‐ and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), and tritium. To complete this assessment small mammals, vegetation, soil, and insect samples were collected from areas within and adjacent to the Beatty, Nevada, LLRW site and from a reference area located approximately 3 km south of the LLRW site. Samples underwent analysis via liquid chromatography tandem mass spectrometry, gas chromatography mass spectrometry, or scintillation spectroscopy depending on the analyte of interest. Small mammal tissues showed maximum concentrations of over 1700 ng/g for PFAS, 1600 ng/g for PCBs, and 10 000 Bq/kg for tritium. The primary contaminants found in soil samples were PCBs, with maximum concentrations exceeding 25 ng/g. Trace amounts of PFAS were also detected in soils and insects. Only qualitative data were obtained from vegetation samples because of the complex matrix of the dominant plant species (creosote bush; Larrea tridentata [Sessé & Moc. ex DC.] Coville). Overall, these data indicate the presence of various anthropogenic contaminants in the ecosystem surrounding the LLRW area, but additional analyses are necessary to confirm the sources and migration pathways of PFAS and PCBs in this hyperarid environment. Environ Toxicol Chem 2021;40:727–734. © 2020 SETAC [ABSTRACT FROM AUTHOR]

Chancelloriids are a poorly understood group of phylogenetically problematic Cambrian metazoans; complete specimens show they were sessile, radially symmetrical, club‐shaped organisms covered with sclerites in the form of rosettes of spines. While isolated sclerites are common components of Cambrian shelly assemblages, they have been relatively little studied. We describe chancelloriid sclerites from a series of nine sections spanning the upper Dyeran to lower Delamaran stages (latest Stage 4 to perhaps basal Wuliuan) from the Pioche–Caliente region of east‐central Nevada, USA. Acid maceration of samples from the Combined Metals, Comet Shale and Susan Duster Limestone members of the Pioche Formation yielded more than 2000 sclerites. Based on careful examination of these sclerites and statistical analyses of co‐occurring sclerite types, we distinguish six species, each with a restricted stratigraphic range. Chancelloria impar Moore sp. nov. is the dominant species in most upper Dyeran samples. Archiasterella cometensis Moore sp. nov. and A. auriculata Moore sp. nov. are rare in the upper Dyeran but abundant in the lowest Delamaran; A. uncinata Moore sp. nov. and C. lilioides Moore sp. nov. replace these in younger samples. A. auriculata is noteworthy for sharing features with species of both Archiasterella and Chancelloria. These results provide further support for the taxonomic tractability and biostratigraphical utility of chancelloriid sclerites; large collections from single horizons allow intraspecific variability to be assessed and species to be distinguished. Our results document a taxonomic turnover in chancelloriids at the Dyeran–Delamaran boundary, showing that not only trilobites were affected at this time. [ABSTRACT FROM AUTHOR]

PREMISE: Understanding edaphic specialization is crucial for conserving rare plants that may need relocation due to habitat loss. Focusing on Eriogonum crosbyae, a rare soil specialist in the Great Basin of the United States, we asked how site‐level variation among volcanic soil outcrops affected plant growth and population distribution. METHODS: We measured emergence, survival, size, and biomass allocation of E. crosbyae seedlings planted in soils collected from 42 outcrops of actual and potential habitat. We also measured phenotypic variation in the wild, documented abiotic and biotic components of E. crosbyae habitat, re‐surveyed Nevada populations, and evaluated occupancy changes over time. RESULTS: Plants responded plastically to edaphic variation, growing larger and allocating relatively more to aboveground tissues in soils with greater nutrient availability and growing smaller in soils higher in copper in the field and the greenhouse. However, the chemical and physical soil properties we measured did not predict site occupancy, nor was plant phenotype in the greenhouse different when plants were grown in soils from sites with different occupation status. We observed occupation status reversals at five locations. CONCLUSIONS: Eriogonum crosbyae performed well in soils formed on hydrothermally altered rocks that are inhospitable to many other plants. Extirpation/colonization events observed were consistent with metapopulation dynamics, which may partially explain the patchy distribution of E. crosbyae among outcrops of potential habitat. While soil properties did not predict site occupancy, early life stages showed sensitivity to soil variation, indicating that seedling dynamics may be important to consider for the conservation of this soil specialist. [ABSTRACT FROM AUTHOR]

Recent high impact wildfires and droughts in California and Nevada have been linked to extremes in the Evaporative Demand Drought Index (EDDI) and Standardized Precipitation Evapotranspiration Index (SPEI), respectively. Both indices are dependent on reference evapotranspiration (ET0). Future changes in ET0 for California and Nevada are examined, calculated from global climate model simulations downscaled by Localized Constructed Analogs (LOCA). ET0 increases of 13–18% at seasonal timescales are projected by late century (2070–2099), with greatest relative increases in winter and spring. Seasonal ET0 increases are most strongly driven by warmer temperatures, with increasing specific humidity having a smaller, but noteworthy, counter tendency. Extreme (95th percentile) EDDI values on the 2‐week timescale have coincided with recent large wildfires in the area. Two‐week EDDI extremes are projected to increase by 6–10 times during summer and 4–6 times during autumn by the end of the century. On multiyear timescales, the occurrence of extreme droughts based on 3‐year SPEI below the historical fifth percentile, similar to that experienced during the 2012–2016 drought across the region, is projected to increase 3–15 times by late century. Positive trends in extreme multiyear droughts will further increase seasonal fire potential through degraded forests and increased fuel loads and flammability. Understanding how these drought metrics change on various climate timescales at the local level can provide fundamental information to support the development of long‐term adaptation strategies for wildland fire and water resource management. Plain Language Summary: Since the start of the 21st century, California and Nevada have observed extreme wildland fires and droughts that have caused devastating impacts to ecosystems and society. A common feature of these events has been very high atmospheric evaporative demand—the "thirst" of the atmosphere—which has largely been driven by increased air temperatures caused by anthropogenic climate change. This study examines projected changes in evaporative demand, which of the input variables are causing those changes and how the frequency of extreme wildfire potential and multiyear droughts will change. Evaporative demand is found to increase during all seasons, and increased temperatures drive most of that change. The likelihood of extreme wildfire potential based on 2‐week periods of elevated evaporative demand during summer and autumn increases substantially. A climatic water balance based on precipitation and evaporative demand indicates extreme 3‐year droughts that hold potential to deplete regional‐scale water supply also become much more likely. Future adaptation planning efforts for wildfire management agencies, forest management, and water resource managers should account for a greater likelihood of more extreme events. Key Points: All climate models show increasing reference evapotranspiration (ET0) through the end of the centuryIncreased air temperature has the greatest contribution to projected ET0 increasesExtreme ET0‐based wildfire potential and 3‐year droughts based on precipitation minus ET0 become much more frequent in the future [ABSTRACT FROM AUTHOR]

As eco‐social work practice and scholarship continues to grow, multiple frameworks are emerging to help guide the work. In this study, we interviewed 59 people affected by environmental injustice. Participants identified components within both environmental injustice and sustainability, as well as gaps that these models individually do not support. Therefore, we suggest that merging environmental justice with sustainability through centering justice (a component within environmental justice), and also finding solutions through technological advances (a component within sustainability), may best support these communities. In addition, the participants discussed the need for support, which social workers can provide. [ABSTRACT FROM AUTHOR]

Increasing salinization is a threat to viticultural production as the quantity and quality of irrigation water decreases. Grapevines are particularly sensitive to chloride ions, but some wild species of Vitis L. have been found to restrict chloride uptake. Therefore, it is possible to breed rootstocks that prevent chloride from reaching the leaves or fruit, where buildup of the ion can reduce photosynthetic capacity and affect fruit and wine quality. A previously developed greenhouse screen for chloride exclusion, which mimics field results, was applied to 325 accessions of 14 Vitis species collected from the southwestern United States and Mexico. While the trait was not clearly associated with any particular species or geographic region, promising chloride‐excluding accessions were identified. Vitis girdiana Munson from southern Nevada and V. X doaniana Munson ex Viala from the border of Texas and Oklahoma both consistently restricted chloride uptake in comparison to 140 Ruggeri (140 Ru), a known salt excluder. In addition, many accessions of V. girdiana from southern Nevada took up less than half the concentration of chloride in the roots as compared with 140 Ru. The prevalence of the chloride exclusion trait across multiple genetic backgrounds indicates that this collection may contain multiple sources for chloride exclusion in grape. This screen is an important first step in the characterization of Vitis rootstock breeding material from the southwestern United States and Mexico. [ABSTRACT FROM AUTHOR]