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In this paper we report chemically resolved measurements of organic aerosol (OA) and related tracers during the Biosphere Effects on Aerosols and Photochemistry Experiment (BEARPEX) at the Blodgett Forest Research Station, California from 15 August-10 October 2007. OA contributed the majority of the mass to the fine atmospheric particles and was predominately oxygenated (OOA). The highest concentrations of OA were during sporadic wild- fire influence when aged plumes were impacting the site. In situ measurements of particle phase molecular markers were dominated by secondary compounds and along with gas phase compounds could be categorized into six factors or sources: (1) aged biomass burning emissions and oxidized urban emissions, (2) oxidized urban emissions (3) oxidation products of monoterpene emissions, (4) monoterpene emissions, (5) anthropogenic emissions and (6) local methyl chavicol emissions and oxidation products. There were multiple biogenic components that contributed to OA at this site whose contributions varied diurnally, seasonally and in response to changing meteorological conditions, e.g. temperature and precipitation events. Concentrations of isoprene oxidation products were larger when temperatures were higher during the first half of the campaign (15 August-12 September) due to more substantial emissions of isoprene and enhanced photochemistry. The oxidation of methyl chavicol, an oxygenated terpene emitted by ponderosa pine trees, contributed similarly to OA throughout the campaign. In contrast, the abundances of monoterpene oxidation products in the particle phase were greater during the cooler conditions in the latter half of the campaign (13 September-10 October), even though emissions of the precursors were lower, although the mechanism is not known. OA was correlated with the anthropogenic tracers 2-propyl nitrate and carbon monoxide (CO), consistent with previous observations, while being comprised of mostly non-fossil carbon (>75 %). The correlation between OA and an anthropogenic tracer does not necessarily identify the source of the carbon as being anthropogenic but instead suggests a coupling between the anthropogenic and biogenic components in the air mass that might be related to the source of the oxidant and/or the aerosol sulfate. Observations of organosulfates of isoprene and α-pinene provided evidence for the likely importance of aerosol sulfate in spite of neutralized aerosol although acidic plumes might have played a role upwind of the site. This is in contrast to laboratory studies where strongly acidic seed aerosols were needed in order to form these compounds. These compounds together represented only a minor fraction (<1 %) of the total OA mass, which may be the result of the neutralized aerosol at the site or because only a small number of organosulfates were quantified. The low contribution of organosulfates to total OA suggests that other mechanisms, e.g. NOx enhancement of oxidant levels, are likely responsible for the majority of the anthropogenic enhancement of biogenic secondary organic aerosol observed at this site. [ABSTRACT FROM AUTHOR]

The purpose of the study was to examine training professionals' insights and beliefs about the challenges they face in training and the corresponding coping mechanisms by analyzing the opinions of training experts. A qualitative implicit method, the Zaltman Metaphor Elicitation Technique, which performs interviews using pictures, was conducted with ten training professionals. Metaphors were widely used, and links between concepts were identified. The training challenges that resulted from the current study included measurement, deadlines, frustration, and keeping current. The study took place in Las Vegas, Nevada, and the interviewees were employed by large hotel-casino corporations. Future studies need to research different sized hospitality institutions and different tourist destinations. Current and future training professionals can use the outcome of the study as a guide to better understanding training challenges and to acquiring the corresponding competencies to be more effective in training. Moreover, the outcome of the paper can be beneficial to industry employees and educators, since training and teaching are in many ways similar. [ABSTRACT FROM AUTHOR]

This paper asks whether speculative house-price pressure in an economic center can spill into related housing markets. In other words, are bubbles contagious? I develop a theoretical model that allows for speculative price appreciation to spread from one market to another. I estimate an error-correction model using quarterly housing data for Las Vegas and Los Angeles and fundamental market variables from 1978 Quarter 2 through 2008 Quarter 1. Las Vegas prices show significant persistence and adjust slowly to disequilibrium. Contagious price and income growth from the Los Angeles market sustained by naive expectations contributed to the bubble that formed in Las Vegas [ABSTRACT FROM AUTHOR]

Hall's (this issue) comment to my paper published in American Antiquity five years ago (Hockett 2005) makes the following statements: (1) I calculated "depositional rates" for a series of Great Basin faunal assemblages; (2) my analysis did not account for atmospheric radiocarbon fluctuations; and (3) my paper argued "against an increase in hunting artiodactyls from the Middle to Late Holocene." He further argues that recalculation of the data I presented demonstrates that both large- and small-game hunting increased from the Middle to the Late Holocene. Hall is wrong on all accounts. I agree, however, that calibrated dates should now be used instead of the raw radiocarbon dates I used in my original paper. Using calibrated dates, however, does nothing to change the initial patterns I outlined five years ago. Three more recent papers (Hockett 2007, 2009; Hockett and Murphy 2009) on large game hunting in the Great Basin also corroborate my 2005 interpretations. [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]

Abstract: This paper presents a study of solute transport through ground water in the saturated zone and the resulting breakthrough curves (BTCs), using a field-scale numerical model that incorporates the processes of advection, dispersion, matrix diffusion in fractured volcanic formations, sorption, and colloid-facilitated transport. Such BTCs at compliance boundaries are often used as performance measures for a site. The example considered here is that of the saturated zone study prepared for the Yucca Mountain license application. The saturated zone at this site occurs partly in volcanic, fractured rock formations and partly in alluvial formations. This paper presents a description of the site and the ground water flow model, the development of the conceptual model of transport, model uncertainties, model validation, and the influence of uncertainty in input parameters on the downstream BTCs at the Yucca Mountain site. [ABSTRACT FROM AUTHOR]

A series of experiments to study the behavior of thick wires (0.5–2 mm in diameter) driven by currents of about 1 MA has recently been conducted on the Zebra facility at the University of Nevada, Reno. The objective of these experiments was to study plasma formation on the surface of conductors under the influence of megagauss magnetic fields. Laser shadowgraphy, filtered optical and extreme ultraviolet photodiodes, and extreme ultraviolet spectroscopy used in the experiments provided data on radial expansion of wires and on plasma radiation. This paper focuses on numerical simulations of these experiments. Simulations with wires having diameters up to 1.6 mm demonstrated plasma formation with temperatures above 3 eV, which is in preliminary agreement with the experiment. For 2-mm-diameter wires, although plasma can be observed in the simulations, it has substantially smaller optical thickness than in the simulations of the smaller diameter wires, and the radiation fluxes prove to be much lower. This can shed light on the experimental results where the radiation of the 2-mm wires was very weak. The simulated time dependences of the wire radii agree rather well with the experimental results obtained using laser diagnostics and visible-light imaging. The experimental data of the photodiodes also agree well with the simulated time dependence of the detected radiation. [ABSTRACT FROM PUBLISHER]

Small area population projections are useful in a range of business applications. This paper uses a case study to show how this type of task can be accomplished by using the Hamilton–Perry method, which is a variant of the cohort-component projection technique. We provide the documentation on the methods, data, and assumptions used to develop two sets of population projections for census tracts in Clark County, Nevada, and discuss specific factors needed to accomplish this task, including the need to bring expert judgment to bear on the task. Our experience suggests that the Hamilton–Perry Method is an important tool and we advise considering it for small forecasting needs in the private sector. [ABSTRACT FROM AUTHOR]

Hyperspectral imaging is a new emerging technology in remote sensing which generates hundreds of images, at different wavelength channels, for the same area on the surface of the Earth. Over the last years, many algorithms have been developed with the purpose of finding endmembers, assumed to be pure spectral signatures in remotely sensed hyperspectral data sets. One of the most popular techniques has been the pixel purity index (PPI). This algorithm is very time-consuming. The reconfigurability, compact size, and high computational power of Field programmable gate arrays (FPGAs) make them particularly attractive for exploitation in remote sensing applications with (near) real-time requirements. In this paper, we present an FPGA design for implementation of the PPI algorithm. Our systolic array design includes a DMA and implements a prefetching technique to reduce the penalties due to the I/O communications. We have also included a hardware module for random number generation. The proposed method has been tested using real hyperspectral data collected by NASA's Airborne Visible Infrared Imaging Spectrometer over the Cuprite mining district in Nevada. Experimental results reveal that the proposed hardware system is easily scalable and able to provide accurate results with compact size in (near) real-time, whichmake our reconfigurable system appealing for on-board hyperspectral data processing. [ABSTRACT FROM AUTHOR]

Geothermal power plants typically show decreasing heat and power production rates over time. Mitigation strategies include optimizing the management of existing wells—increasing or decreasing the fluid flow rates across the wells—and drilling new wells at appropriate locations. The latter is expensive, time-consuming, and subject to many engineering constraints, but the former is a viable mechanism for periodic adjustment of the available fluid allocations. In this study, we describe a new approach combining reservoir modeling and machine learning to produce models that enable such a strategy. Our computational approach allows us, first, to translate sets of potential flow rates for the active wells into reservoir-wide estimates of produced energy, and second, to find optimal flow allocations among the studied sets. In our computational experiments, we utilize collections of simulations for a specific reservoir (which capture subsurface characterization and realize history matching) along with machine learning models that predict temperature and pressure timeseries for production wells. We evaluate this approach using an "open-source" reservoir we have constructed that captures many of the characteristics of Brady Hot Springs, a commercially operational geothermal field in Nevada, USA. Selected results from a reservoir model of Brady Hot Springs itself are presented to show successful application to an existing system. In both cases, energy predictions prove to be highly accurate: all observed prediction errors do not exceed 3.68% for temperatures and 4.75% for pressures. In a cumulative energy estimation, we observe prediction errors that are less than 4.04%. A typical reservoir simulation for Brady Hot Springs completes in approximately 4 h, whereas our machine learning models yield accurate 20-year predictions for temperatures, pressures, and produced energy in 0.9 s. This paper aims to demonstrate how the models and techniques from our study can be applied to achieve rapid exploration of controlled parameters and optimization of other geothermal reservoirs. [ABSTRACT FROM AUTHOR]

Desert springs, often the sole sources of water for wildlife and cattle, support wetland and wetland/upland transition ecosystems including rare and endemic species. In the basin and range province in Nevada, USA, springs in the Great Basin and Mojave deserts are sustained by interconnected deep carbonate and shallow basin-fill aquifers which are threatened by proposed groundwater withdrawal to sustain rapidly expanding urban areas, a common problem in arid regions worldwide. This paper draws on historic groundwater data, groundwater modeling, and studies of environmental controls of spring ecosystems to speculate on the potential effects of groundwater withdrawal and water table decline on spring-supported vegetation. The focus is on springs in the Great Basin and Mojave deserts representative of those that may be affected by future, planned groundwater withdrawal. Groundwater withdrawal is expected to reduce spring discharge directly through reduced flows from the shallow basin-fill aquifer or through reduction of the hydraulic head of the deep carbonate aquifer. This flow reduction will truncate the outflow stream, reducing the areal cover of wetland and wetland/upland transition vegetation. Lowering the local water table may also reduce the amount of upland phreatophytic vegetation by causing water levels to drop below plant rooting depths. Percolation of salts to surface soils may be reduced, eventually altering desert shrub cover from halophytes to nonhalophytes. The extent of these effects will vary among springs, based on their distance from extraction sites and location relative to regional groundwater flow paths. On-site monitoring of biotic variables (including cover of selected hygrophytes and phreatophytes) should be a necessary complement to the planned monitoring of local hydrologic conditions. [ABSTRACT FROM AUTHOR]

This paper investigates the formation mechanisms for a local wind phenomenon known as Washoe Zephyr that occurs frequently in the lee of the Sierra Nevada. Unlike the typical thermally driven slope flows with upslope wind during daytime and downslope at night, the Washoe Zephyr winds blow down the lee slopes of the Sierra Nevada in the afternoon against the local pressure gradient. Long-term hourly surface wind data from several stations on the eastern slope of the Sierra Nevada and rawinsonde sounding data in the region are analyzed and numerical simulations are performed to test the suggested hypotheses on the formation mechanisms for this interesting phenomenon. The results from surface and upper-air climate data analyses and numerical modeling indicate that the Washoe Zephyr is primarily a result of a regional-scale pressure gradient that develops because of asymmetric heating of the atmosphere between the western side of the Sierra Nevada and the elevated, semiarid central Nevada and Great Basin on the eastern side of the Sierra Nevada. The frequent influence of the Pacific high on California in the summer season helps to enhance this pressure gradient and therefore strengthen the flow. Westerly synoptic-scale winds over the Sierra Nevada and the associated downward momentum transfer are not necessary for its development, but strong westerly winds aloft work in concert with the regional-scale pressure gradient to produce the strongest Washoe Zephyr events. [ABSTRACT FROM AUTHOR]

For more than two decades, an extensive scientific effort has been underway to determine whether Yucca Mountain, Nevada, is a suitable site for a deep underground repository for spent nuclear fuel and high-level radioactive waste. Even though the geologic site is stable, additional engineered barriers are planned, including waste packages, drip shields, and tunnel inverts that will be within the emplacement tunnels. Research is under way into the best materials for corrosion prevention in those engineered barriers to ensure their long-term mechanical integrity. [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]

Las Vegas, Nevada, is typically recognised as a place via a single urban gesture, that gesture being Las Vegas Boulevard, which is more commonly referred to as "The Strip". In constructing a thesis around the theme, "Here or There? Interconnections between the Global and the Local", one cannot ignore the invitation to discuss globalisation and its effects on a particular local fabric. For the purpose of this text, globalisation can be thought of as what Carmona et al describe as an intricate series of events leading to the world "becoming increasingly interconnected, with centralised decision making exploiting economies of scale and standardisation" (2003: 101). The centralised decision-making process for The Strip is evident in the strategy to develop individually themed casino resorts along Las Vegas Boulevard that respond to a competitive economy, thus creating a newly standardised landscape. If we also understand that globalisation can be thought of as the development of an interconnected world where economic, political and cultural boundaries can be easily crossed, this work can begin to define how the Las Vegas Strip is a genuinely invented global landscape. This paper addresses the "here-ness" as well as the "there-ness" of The Strip, while offering a dialectical framework for establishing a meaning of place by having `there' placed `here'. By employing semiological interpretations of real landscapes from around the globe (for example, Venturi et at, 1972), The Strip becomes a newly invented landscape of "simulations" (Baudrillard, 1988). As such, The Strip acts as a narrative that forms a unique place, opening the door to questions of authenticity and identity. This paper concludes by focusing on the question of "Here or There?" as an appropriate deviation from the assumed role that the post-modern landscape of the Las Vegas Strip plays. This work is intended to be a point of departure from the frequent criticism of the Las Vegas Strip as simply an `invented' space and focuses on the potential of this constructed landscape for providing a genuinely positive, place- based experience that focuses on the interconnections between `here' and `there'. [ABSTRACT FROM AUTHOR]

This paper measures the effect of health risk on housing values by exploiting a natural experiment that mitigates both econometric problems. The analysis focuses on Churchill, an isolated county in Nevada where residents have recently experienced a severe increase in pediatric leukemia. Housing prices are compared before and after the increase with a nearby county acting as a control group. The variation in health risk over time makes it possible to control for unobserved differences across locations. In addition, because the leukemia cases were unanticipated there is no reason to expect sorting of households according to preferences prior to the increase. Finally, because many houses were sold repeatedly during the sample period it is possible to control for unobserved property-specific heterogeneity. Housing prices in the affected county closely followed trends in housing prices for the control county and the rest of the state of Nevada during the period leading up to the leukemia increase. Then, beginning when eight children were diagnosed in 2000, housing prices in the affected county decline significantly. Least-squares estimates indicate that houses sold during the period of maximum risk sold for 15.6 percent less than equivalent houses not affected by the leukemia increase.

This paper describes the development and use of a particle-tracking model to perform radionuclide-transport simulations in the unsaturated zone at Yucca Mountain, Nevada. The goal of the effort was to produce a computational model that can be coupled to the project''s calibrated 3D site-scale flow model so that the results of that effort could be incorporated directly into the Total System Performance Assessment (TSPA) analyses. The transport model simulates multiple species (typically 20 or more) with complex time-varying and spatially varying releases from the potential repository. Water-table rise, climate-change scenarios, and decay chains are additional features of the model. A cell-based particle-tracking method was employed that includes a dual-permeability formulation, advection, longitudinal dispersion, matrix diffusion, and colloid-facilitated transport. This paper examines the transport behavior of several key radionuclides through the unsaturated zone using the calibrated 3D unsaturated flow fields. Computational results illustrate the relative importance of fracture flow, matrix diffusion, and lateral diversion on the distribution of travel times from the simulated repository to the water table for various climatic conditions. Results also indicate rapid transport through fractures for a portion of the released mass. Further refinement of the model will address several issues, including conservatism in the transport model, the assignment of parameters in the flow and transport models, and the underlying assumptions used to support the conceptual models of flow and transport in the unsaturated zone at Yucca Mountain. [Copyright &y& Elsevier]

Background: Globally, the most important human rights and public health issue that sex workers face is their experience of high levels of violence (Kinnell, 2006, Kinnell, 2008, Alexander, 1999). Deering's systematic review estimated levels of sexual violence in sex working populations as being between 14% and 54% (Deering et al, 2014). Aims: This international, robust mixed methods study will explore the frequency of sexual violence against sex workers, barriers in criminal justice and the legal consciousness of sex workers regarding their rights and consent. The hypothesis to be tested is that the safety of sex workers from sexual violence is mediated by the differing legal contexts of sex work environments. We will compare experiences across research sites in the context of legalisation (Nevada USA), client criminalisation (Northern Ireland), decriminalisation (New Zealand) and partial criminalisation (England, Scotland and Wales) [henceforth ESW]. Methods: An international survey (n = 1,000) will be translated into several languages, to disaggregate experiences by demographic categories (gender, ethnicity, sexual orientation) and sex work sector (including online, street-based and brothels). Interviews (n = 100) with sex workers, police, prosecutors and service providers will be thematically analysed to explore legal consciousness, why the patterns occur and contextualise the statistical findings. These data will be supplemented with comparative legislative, policy and case analysis. Research study data will be used to compare the social factors and legal norms shaping sex workers experiences of sexual violence, justice and support interventions. Recommendations for a 'best practice' review of legal improvements and support interventions will be produced following completion of the study. Given the sensitive nature of the research, robust ethical and data protection mechanisms are in place. The research has ethical approval from each research site, an Advisory Board and trained, paid peer researchers to assist with data gathering, analysis and dissemination. The study will report findings in 2023/2024. [ABSTRACT FROM AUTHOR]

Seismicity induced by fluid injection including wastewater injection, hydrofracking and enhanced geothermal system (EGS) site production draws public attention. Dense arrays have been deployed to improve monitoring capability. In 2016 March, the PoroTomo experiment deployed an 8.6-km-long fibre-optic cable for distributed acoustic sensing (DAS) in the geothermal field at Brady Hot Springs, Nevada, covering an area of 1.5 by 0.5 km. The goal was to assess an integrated technology for characterizing and monitoring temporal changes in the rock mechanical properties of an EGS reservoir in three dimensions. We applied a neural network designed for earthquake detection called ADE-Net2 to the DAS data set to detect seismic events in continuous records. We were able to detect a total of 90 earthquakes, which included 21 events that had not been reported by a previous template-matching study. Additionally, we were able to successfully detect almost all of the active source signals, with only seven events being missed. We used the STA/LTA (short-/long-term average) method to pick arrivals and a clustering method to remove outliers. We initially tried a standard event location algorithm, but the low signal-to-noise ratio resulted in significant picking uncertainty that is up to ∼0.5 s, leading to large location uncertainty. Therefore, we developed a new location method based on the similarity between the theoretical traveltime curve and picked moveout. A grid search scheme was adopted to find the optimal point at which the traveltime curve is most similar to the picked one. Most newly detected earthquakes locate southwest of the DAS array, where five earthquakes were reported by a local seismic network. The plant began shutting down at 19:15 UTC on the March 13, and most earthquakes occurred on the March 14, indicating a relationship between the seismicity and the pressure changes caused by the shutdown of the plant. The pressure changes at epicentres obtained from a simplified model range from 71 to 157 kPa, exceeding a typical earthquake trigger threshold of 10 kPa. [ABSTRACT FROM AUTHOR]

The short-wave infrared (SWIR) module of the Tropospheric Monitoring Instrument (TROPOMI) on board the ESA's Sentinel-5 precursor (S5p) satellite has been very stable during its 5 years in orbit. Calibration was performed on the ground, complemented by measurements during in-flight instrument commissioning. The radiometric response and general performance of the SWIR module are monitored by on-board calibration sources. We show that after 5 years in orbit, TROPOMI-SWIR has continued to show excellent performance with degradation of at most 0.1 % in transmission and having lost less than 0.3 % of the detector pixels. Independent validation of the instrument calibration, via vicarious calibration, can be done through comparisons with ground-based reflectance data. In this work, ground measurements at the Railroad Valley Playa, a valley in central Nevada that is often used as a reference for satellite measurements, are used to perform vicarious calibration of the TROPOMI-SWIR measurements. This is done using dedicated measurement campaigns as well as automated reflectance measurements within the RADCALNET programme. As such, TROPOMI-SWIR is an excellent test case to explore the methodology of vicarious calibration applied to infrared spectroscopy. Using methodology developed for the vicarious calibration of the OCO-2 and GOSAT missions, the absolute radiometry of TROPOMI-SWIR performance is independently verified to be stable down to ∼ 6 %–10 % using the Railroad Valley when both the absolute and relative radiometric calibrations are applied. Differences with the on-board calibration originate from the bidirectional reflection distribution function (BRDF) effects of the desert surface, the large variety in viewing angles, and the different sizes of footprints of the TROPOMI pixels. Vicarious calibration is shown to be an additional valuable tool in validating radiance-level performances of infrared instruments such as TROPOMI-SWIR in the field of atmospheric composition. It remains clear that for instruments of similar design and resolution to TROPOMI-SWIR, on-board calibration sources will continue to provide superior results due to the limitations of the vicarious calibration method. [ABSTRACT FROM AUTHOR]

This article explores the challenges Nevada faces in managing its water resources, particularly groundwater, due to climate change and overpopulation. It discusses the state's water management policies, including the designation of Critical Management Areas (CMAs) and the implementation of sustainable water use practices. The case study of the Diamond Valley basin highlights the state's user-oriented approach to water law and the potential for future changes in Nevada's water management policies. The article also discusses the controversial Diamond Valley decision, which deviates from the doctrine of prior appropriation and raises concerns about the devaluation of priority and vested rights. It examines the impact of the Diamond Valley Groundwater Management Plan (GMP) on water rights and the practice of water banking, and discusses the implementation of GMPs in Nevada and their potential impact on water management policies. The future of Nevada's water law is uncertain, with a complete overhaul of the system being a possibility. [Extracted from the article]

Several similar indicators in Nevada (USA) and South Yakutia (Russia) gold-bearing provinces have been identified based on modern tectonic, geophysical and seismic tomography observations, followed by the analysis of the main geodynamic factors of the formation and distribution of large gold-bearing provinces in the North Pacific. One of the significant metallogenic peculiarities is a wide variety of formational and mineral deposits concentrated in the areas. Both provinces are situated at active margins surrounded by fold-thrust belts. In South Yakutia, a combination of sublatitudinal Baikal-Elkon-Ulkan and submeridional Seligdar-Verkhnetimpon gravity field gradient zones is recorded. In contrast, significant positive gravity anomalies of the Northern Nevada Rift and higher-order gradient zones are presented in Nevada. Large pluton and transform fault zones in both provinces support a conclusion about the fundamental role of geodynamic factors in developing ore-magmatic systems in the regions. Significant differences in the scale of the gold mineralization in the considered provinces are explained by the existence under the North American continent not only of the Mendocino transform fault zone but also of the Juan de Fuca paleo-spreading center. In contrast, the Inagli-Konder-Feklistov magmatic-metallogenic belt alone controls mineralization under the Asian continent. [ABSTRACT FROM AUTHOR]

Pollen identification is necessary for several subfields of geology, ecology, and evolutionary biology. However, the existing methods for pollen identification are laborious, time-consuming, and require highly skilled scientists. Therefore, there is a pressing need for an automated and accurate system for pollen identification, which can be beneficial for both basic research and applied issues such as identifying airborne allergens. In this study, we propose a deep learning (DL) approach to classify pollen grains in the Great Basin Desert, Nevada, USA. Our dataset consisted of 10,000 images of 40 pollen species. To mitigate the limitations imposed by the small volume of our training dataset, we conducted an in-depth comparative analysis of numerous pre-trained Convolutional Neural Network (CNN) architectures utilizing transfer learning methodologies. Simultaneously, we developed and incorporated an innovative CNN model, serving to augment our exploration and optimization of data modeling strategies. We applied different architectures of well-known pre-trained deep CNN models, including AlexNet, VGG-16, MobileNet-V2, ResNet (18, 34, and 50, 101), ResNeSt (50, 101), SE-ResNeXt, and Vision Transformer (ViT), to uncover the most promising modeling approach for the classification of pollen grains in the Great Basin. To evaluate the performance of the pre-trained deep CNN models, we measured accuracy, precision, F1-Score, and recall. Our results showed that the ResNeSt-110 model achieved the best performance, with an accuracy of 97.24%, precision of 97.89%, F1-Score of 96.86%, and recall of 97.13%. Our results also revealed that transfer learning models can deliver better and faster image classification results compared to traditional CNN models built from scratch. The proposed method can potentially benefit various fields that rely on efficient pollen identification. This study demonstrates that DL approaches can improve the accuracy and efficiency of pollen identification, and it provides a foundation for further research in the field. [ABSTRACT FROM AUTHOR]

Lake Mead located in the Arizona–Nevada region of the Mohave Dessert is a unique and complex water system whose flow follows that of a warm monomictic lake. Although monomictic lakes experience thermal stratification for almost the entire year with a period of complete mixing, the lake on occasion deviates from this phenomenon, undergoing incomplete turnovers categorized with light stratifications every other year. The prolonged drought and growing anthropogenic activities have the potential to considerably impact the quality of the lake. Lake Mead and by extension the Boulder Basin receive cooler flow from the Colorado River and flow with varying temperatures from the Las Vegas Wash (LVW), which impacts its stratification and complete turnovers. This study analyzes four key water quality parameters (WQPs), namely, total dissolved solids (TDS), total suspended solids (TSS), temperature, and dissolved oxygen (DO), using statistical and spatial analyses to understand their variations in light of the lake stratifications and turnovers to further maintain its overall quality and sustainability. The study also evaluates the impacts of hydrological variables including in and out flows, storage, evaporation, and water surface elevation on the WQPs. The results produced from the analysis show significant levels of TDS, TSS, and temperature from the LVW and Las Vegas Bay regions compared with the Boulder Basin. LVW is the main channel for conveying effluents from several wastewater treatment facilities into the lake. We observed an increase in the levels of TDS, TSS, and temperature water quality in the epilimnion compared with the other layers of the lake. The metalimnion and the hypolimnion layer, however, showed reduced DO due to depletion by algal blooms. We observed statistically significant differences in the WQPs throughout various months, but not in the case for season and year, an indication of relatively consistent variability throughout each season and year. We also observed a no clear trend of influence of outflows and inflows on TDS, temperature, and DO. TSS concentrations in the lake, however, remained constant, irrespective of the inflows and outflows, possibly due to the settling of the sediments and the reservoir capacity. [ABSTRACT FROM AUTHOR]

This paper presents a program for counseling students enrolled in an online charter school located in Las Vegas, Nevada. The author presents a review of the process to establish an online school in Nevada and a unique model for delivery of services that combines face-to-face instruction and online education. The author describes the development of a counseling program that includes strategies for encouraging college attendance. Students and parents are given an orientation to online education, online test-taking strategies, and online resources for admission to college. A sample of a web page for counseling and guidance is provided. In addition, this paper summarizes an intervention and research study conducted by the author while serving as Director of Counseling and Director of Testing. This paper describes a counselor-led intervention to improve mathematics proficiency, help parents and students access learning and test-taking strategies available online, and help parents and students transition to a distance-learning school. The author explores the connection between failure on the test and failure to attend college. The counseling program was developed to expose parents and students to resources that promote college attendance. This action research study was designed to improve achievement in mathematics and prepare students for the mathematics proficiency test. The scores on the Nevada Proficiency Test in Mathematics were used to measure improvement. As a result of the implementation of test-taking strategies, there was an improvement in the number of senior students passing the test. Before the implementation of the strategies, the percentage of students passing the test ranged from 0% in February 2003 to 7% in April 2003. The Clark County School District has an average passing rate of 20%. After the implementation of the strategies, 30% of the students tested passed the test (November 2003). The results of the parent survey were positive with a majority of parents participating in the orientation and stating that the orientation provided excellent information.

In the American West, wildfires and earthquakes are increasingly threatening the archaeological, historical, and tribal resources that define the collective identity and connection with the past for millions of Americans. The loss of said resources diminishes societal understanding of the role cultural heritage plays in shaping our present and future. This paper examines the viability of employing stationary and SLAM-based terrestrial laser scanning, close-range photogrammetry, automated surface change detection, GIS, and WebGL visualization techniques to enhance the preservation of cultural resources in California. Our datafication approach combines multi-temporal remote sensing monitoring of historic features with legacy data and collaborative visualization to document and evaluate how environmental threats affect built heritage. We tested our methodology in response to recent environmental threats from wildfire and earthquakes at Bodie, an iconic Gold Rush-era boom town located on the California and Nevada border. Our multi-scale results show that the proposed approach effectively integrates highly accurate 3D snapshots of Bodie's historic buildings before/after disturbance, or post-restoration, with surface change detection and online collaborative visualization of 3D geospatial data to monitor and preserve important cultural resources at the site. This study concludes that the proposed workflow enhances the monitoring of at-risk California's cultural heritage and makes a call to action to employ remote sensing as a pathway to advanced planning. [ABSTRACT FROM AUTHOR]

Studying the temporal and spatial evolution trends in earthquakes in an area is beneficial for determining the earthquake risk of the area so that local governments can make the correct decisions for disaster prevention and reduction. In this paper, we propose a new method for analyzing the temporal and spatial evolution trends in earthquakes based on earthquakes of magnitude 3.0 or above from 1980 to 2019 in California and Nevada. The experiment's results show that (1) the frequency of earthquake events of magnitude 4.5 or above present a relatively regular change trend of decreasing–rising in this area; (2) by using the weighted average center method to analyze the spatial concentration of earthquake events of magnitude 3.0 or above in this region, we find that the weighted average center of the earthquake events in this area shows a conch-type movement law, where it moves closer to the center from all sides; (3) the direction of the spatial distribution of earthquake events in this area shows a NW–SE pattern when the standard deviational ellipse (SDE) method is used, which is basically consistent with the direction of the San Andreas Fault Zone across the north and south of California; and (4) the spatial distribution pattern of the earthquake events in this region is found to be clustered using the global spatial autocorrelation analysis method. This study provides a new perspective for the exploration of the temporal and spatial evolution trends in earthquakes and understanding the earthquake risk in an area. [ABSTRACT FROM AUTHOR]

This paper describes a recent effort to pass some "anti-cult" legislation in Nevada. The effort exemplified a new consumer-oriented approach to such matters that seeks to treat religious groups similarly to charitable organizations, and implicitly defines religion as a consumer good to be regulated by government. The bill would have authorized a number of civil and state actions against religions, it evoked considerable controversy before being defeated, with Mormon legislators playing a key role in the bill's defeat. A number of more liberal and moderate members of the legislature supported the legislation, however Implications of this approach are discussed. [ABSTRACT FROM AUTHOR]

This paper relates events surrounding the establishment of the Pyramid Lake Indian Reservation in vestem Nevada and its subsequent nineteenth century history. Discussion will focus on natural resources associated with the reserved lands. Federal Indian policy, national popular attitudes, and the development of Nevada itself, are all important to understanding the pressures placed on those resources during the early reservation period. The type of interethnic relations established during this time stabilized and strongly influenced the later history of Northern Paiutes in this area. [ABSTRACT FROM AUTHOR]

The 1870 Ghost Dance has posed at least two problems for students of Americen Indian history: (1) Whether it should be viewed as an episode of Basin-Plateau recurrent religious ceremonialism, i.e., Spler's Prophet Dance. or as a religious movement whose genesis lies in socio-eonomic deprivation; (2) How to explain its enigmatic central doctrine of resurrection when ritual avoidance of the dead is a marked feature of Northern Paiute culture? This paper will show that in its Walker River Reservation place of origin the 1870 Ghost Dance was a transformative movement which arose from loss of lands, frustration and misery occasioned by Euro-American expansionism. At a time of epidemics and starvation the prophet Wodziwob preached the return of the dead and restoration of the ecology at Round Dances. Deprivation was keenly felt by the Palute because curing and the food quest were two cultural foci; they perceived Wodziwob to be a "crisisbroker," a shaman capable of resurrecting the large numbers of recently deceased, and a Round Dance leader possessed with powers of weathercontrol to improve the food situation. Two functions of the 1870 Ghost Dance, then, were as a curing rite (writ large) and an "Increase ceremony." A third function is suggested. Originating from Fish Lake Valley, Wodziwob, or Flah Lake Joe as he was also known, may have attempted to introduce the annual mourning ceremony of the Fish Lake Valley Palute to his northern conjurers upon emigrating to the Walker River Reservation. [ABSTRACT FROM AUTHOR]

Subsurface characterization is crucial for geothermal energy exploration and production. Yet hydrothermal reservoirs usually reside in highly fractured and faulted zones where accurate characterization is very challenging because of low signal-to-noise ratios of land seismic data and lack of coherent reflection signals. We perform an active-source seismic characterization for the Blue Mountain geothermal field in Nevada using active seismic data to reveal the elastic medium property complexity and fault distribution at this field. We first employ an unsupervised machine learning method to attenuate groundroll and near-surface guided-wave noise and enhance coherent reflection and scattering signals from noisy seismic data. We then build a smooth initial P-wave velocity model based on an existing magnetotellurics survey result, and use 3D first-arrival traveltime tomography to refine the initial velocity model. We then derive a set of elastic wave velocities and anisotropic parameters using elastic full-waveform inversion, and obtain PP and PS images using elastic reverse-time migration. We identify major faults by analyzing the variations of seismic velocities and anisotropy parameters, and reveal mid- to small-scale faults by applying a supervised machine learning method to the seismic migration images. Our characterization reveals complex velocity heterogeneities and anisotropies, as well as faults, with a high spatial resolution. These results can provide valuable information for optimal placement of future injection and production wells to increase geothermal energy production at the Blue Mountain geothermal power plant. [ABSTRACT FROM AUTHOR]

The geologically rapid appearance of fossils of modern animal phyla within Cambrian strata is a defining characteristic of the history of life on Earth. However, temporal calibration of the base of the Cambrian Period remains uncertain within millions of years, which has resulted in mounting challenges to the concept of a discrete Cambrian explosion. We present precise zircon U–Pb dates for the lower Wood Canyon Formation, Nevada. These data demonstrate the base of the Cambrian Period, as defined by both ichnofossil biostratigraphy and carbon isotope chemostratigraphy, was younger than 533 Mya, at least 6 My later than currently recognized. This new geochronology condenses previous age models for the Nemakit–Daldynian (early Cambrian) and, integrated with global records, demonstrates an explosive tempo to the early radiation of modern animal phyla. [ABSTRACT FROM AUTHOR]

Wildfire events are becoming more frequent and severe on a global scale. Rising temperatures, prolonged drought, and the presence of pyrophytic invasive grasses are contributing to the degradation of native vegetation communities. Within the Great Basin region of the western U.S., increasing wildfire frequency is transforming the ecosystem toward a higher degree of homogeneity, one dominated by invasive annual grasses and declining landscape productivity. Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) are a species of conservation concern that rely on large tracts of structurally and functionally diverse sagebrush (Artemisia spp.) communities. Using a 12-year (2008–2019) telemetry dataset, we documented immediate impacts of wildfire on demographic rates of a population of sage-grouse that were exposed to two large wildfire events (Virginia Mountains Fire Complex—2016; Long Valley Fire—2017) near the border of California and Nevada. Spatiotemporal heterogeneity in demographic rates were accounted for using a Before-After Control-Impact Paired Series (BACIPS) study design. Results revealed a 40% reduction in adult survival and a 79% reduction in nest survival within areas impacted by wildfires. Our results indicate that wildfire has strong and immediate impacts to two key life stages of a sagebrush indicator species and underscores the importance of fire suppression and immediate restoration following wildfire events. [ABSTRACT FROM AUTHOR]