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Focuses on the concept of satellite settlements in relation to working environment in Steptoe City, Nevada. Characteristics of satellite settlements; Existence of neighborhoods in company towns; Role of marginal neighborhood on socioeconomic system.

The energy equation is an expression of the first law of thermodynamics or the law of conservation of energy. According to the first law of thermodynamics, the externally applied work to a system is equal to the sum of dissipation energy and Helmholtz free energy of the system. However, most of the currently available stress–dilatancy relationships are based on the energy equation of Taylor-Cam Clay type, which hypothesizes that the applied plastic work is equal solely to the frictional dissipation energy. The Helmholtz free energy has been completely neglected. Recently, observed from acoustic experiments, it has been recognized that Helmholtz free energy can be caused by deformation mechanisms other than friction between particles. Thus, it is necessary to include additional terms in the energy equation in order to correctly model the stress-dilatancy behavior. This paper addresses the issue regarding the balance of this energy equation. Analyses of experimental results are presented. Specific forms of the frictional energy and Helmholtz free energy are proposed. The proposed energy equation is verified with the experimental data obtained from Silica sand, Ottawa sand, and Nevada sand. [ABSTRACT FROM AUTHOR]

The article reports that documents relating to the safety of the proposed nuclear-waste repository at Yucca Mountain in Nevada may have been falsified. A hydrologist at the U.S. Geological Survey (USGS), who was studying how water flowed through the mountain, faked documentation on the times and dates at which certain geological samples were taken from the site. The water data are crucial because the repository's safety depends heavily on how wet it is likely to get inside, and on how long it takes for water to escape from the mountain rock into surrounding river systems.

This paper reviews different approaches to the problem of finding the shape of the basement buried under sedimentary basins from gravity data and explores the applicability of a recently proposed method to a well-constrained real case, comparing the results obtained with the models computed using a variety of techniques. Many gravity inversion techniques to estimate the depth to basement based on rather different approaches have been proposed. As is well known, the interpretation of gravity data requires certain assumptions about the source, aimed at constraining the solution of an ambiguous problem. The different approaches imply different kinds of solutions, namely a density contrast distribution at depth, or a grid defining the depth to basement in the entire area of study or several single depth estimates. Each approach has its own advantages and weaknesses. In this context, special attention is given to the ITerative RESCaling method (ITRESC), which has been recently proposed. In this method, there is no need to assume a density function, which is estimated by a data-driven procedure and then used to generate a grid of the depth to basement. This technique is based on the depth–gravity relation plot, illustrating the link between the depth to basement, known at some control points (e.g., boreholes or interpretation of other geophysical data), and the values of the residual gravity anomaly. An important feature of the ITRESC method is that borehole control points are used globally rather than locally, providing constraints for all parts of the model. The main features of this innovative method are illustrated and evaluated by its application to the gravity anomalies of the Yucca Flat basin (Nevada). The results are compared with models obtained by previous gravity interpretations and by the processing of other geological and geophysical data. [ABSTRACT FROM AUTHOR]

Methods for estimating juvenile survival of wildlife populations often rely on intensive data collection efforts to capture and uniquely mark individual juveniles and observe them through time. Capturing juveniles in a time frame sufficient to estimate survival can be challenging due to narrow and stochastic windows of opportunity. For many animals, juvenile survival depends on postnatal parental care (e.g., lactating mammals). When a marked adult gives birth to, and provides care for, juvenile animals, investigators can use the adult mark to locate and count unmarked juveniles. Our objective was to leverage the dependency between juveniles and adults and develop a framework for estimating reproductive rates, juvenile survival, and detection probability using repeated observations of marked adult animals with known fates, but imperfect detection probability, and unmarked juveniles with unknown fates. Our methods assume population closure for adults and that no juvenile births or adoptions take place after monitoring has begun. We conducted simulations to evaluate methods and then developed a field study to examine our methods using real data consisting of a population of mule deer in a remote area in central Nevada. Using simulations, we found that our methods were able to recover the true values used to generate the data well. Estimates of juvenile survival rates from our field study were 0.96, (95% CRI 0.83–0.99) for approximately 32-day periods between late June and late August. The methods we describe show promise for many applications and study systems with similar data types, and our methods can be easily extended to unmanned aerial platforms and cameras that are already commercially available for the types of images we used. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to describe the development, actions, and evaluation of a university-based, transdisciplinary coalition so that the model may be replicated in other university or multidisciplinary systems. The University of Nevada Las Vegas (UNLV) Mental and Behavioral Health Coalition addresses Nevada's workforce shortages through multi-disciplinary faculty collaboration among seven training programs at UNLV that produce mental health professionals. The coalition's collaborative approach to solution-generating work has served as a catalyst for professional integration in the community as a whole. [ABSTRACT FROM AUTHOR]

Underground gold mines in Nevada are exploiting increasingly deeper ore bodies comprised of weak to very weak rock masses. The Rock Mass Rating (RMR) classification system is widely used at underground gold mines in Nevada and is applicable in fair to good-quality rock masses, but is difficult to apply and loses reliability in very weak rock mass to soil-like material. Because very weak rock masses are transition materials that border engineering rock mass and soil classification systems, soil classification may sometimes be easier and more appropriate to provide insight into material behavior and properties. The Unified Soil Classification System (USCS) is the most likely choice for the classification of very weak rock mass to soil-like material because of its accepted use in tunnel engineering projects and its ability to predict soil-like material behavior underground. A correlation between the RMR and USCS systems was developed by comparing underground geotechnical RMR mapping to laboratory testing of bulk samples from the same locations, thereby assigning a numeric RMR value to the USCS classification that can be used in spreadsheet calculations and geostatistical analyses. The geotechnical classification system presented in this paper including a USCS-RMR correlation, RMR rating equations, and the Geo-Pick Strike Index is collectively introduced as the Weak Rock Mass Rating System (W-RMR). It is the authors' hope that this system will aid in the classification of weak rock masses and more usable design tools based on the RMR system. More broadly, the RMR-USCS correlation and the W-RMR system help define the transition between engineering soil and rock mass classification systems and may provide insight for geotechnical design in very weak rock masses. [ABSTRACT FROM AUTHOR]

Wraparound is a widely-implemented team-based care coordination process for youth with serious emotional and behavioral needs. Wraparound has a positive evidence base; however, research has shown inconsistency in the quality of its implementation that can reduce its effectiveness. The current paper presents results of three studies used to examine psychometrics, reliability, and validity of a measure of wraparound fidelity as assessed during team meetings called the Team Observation Measure (TOM). Analysis of TOM results from 1,078 team observations across 59 sites found good overall internal consistency (α = 0.80), but constrained variability, with the average team rated as having 78 % of indicators of model adherent wraparound present, 11 % absent, and 11 % not applicable. A study of N = 23 pairs of raters found a pooled Kappa statistic of 0.733, indicating substantial inter-rater reliability. Higher agreement was found between external evaluators than for pairs of raters that included an external evaluator and an internal rater (e.g., supervisor or coach). A validity study found no correlation between the TOM and an alternate fidelity instrument, the Wraparound Fidelity Index (WFI), at the team level. However, positive correlations between mean program-level TOM and WFI scores provide support for TOM validity as a summative assessment of site- or program-level fidelity. Implications for TOM users, measure refinement, and future research are discussed. [ABSTRACT FROM AUTHOR]

Background: Regular school attendance is foundational to children's success but school absenteeism is a common, serious, and highly vexing problem. Researchers from various disciplines have produced a rich yet diverse literature for conceptualizing problematic absenteeism that has led to considerable confusion and lack of consensus about a pragmatic and coordinated assessment and intervention approach. Objective: To lay the foundation and suggested parameters for a Response to Intervention (RtI) model to promote school attendance and address school absenteeism. Methods: This is a theoretical paper guided by a systematic search of the empirical literature related to school attendance, chronic absenteeism, and the utilization of an RtI framework to address the needs of school-aged children and youth. Results: The RtI and absenteeism literature over the past 25 years have both emphasized the need for early identification and intervention, progress monitoring, functional behavioral assessment, empirically supported procedures and protocols, and a team-based approach. An RtI framework promotes regular attendance for all students at Tier 1, targeted interventions for at-risk students at Tier 2, and intense and individualized interventions for students with chronic absenteeism at Tier 3. Conclusions: An RtI framework such as the one presented here could serve as a blueprint for researchers as well as educational, mental health, and other professionals. To develop this model and further enhance its utility for all youth, researchers and practitioners should strive for consensus in defining key terms related to school attendance and absenteeism and focus more on prevention and early intervention efforts. [ABSTRACT FROM AUTHOR]

Maar volcanoes are generally understood to be the result of highly energetic, explosive interaction between magma and water (groundwater or surface water). Two end-member conceptual models have been proposed to explain the dimensions (diameter, depth) of maar craters: (1) an incremental growth model, where a crater grows due to subsidence and ejection of debris over the course of many explosions, and the final size is an integrated result of multiple explosive events; (2) a model in which the dimensions of a maar crater are the result of the largest single explosion during the lifetime of the maar (major-explosion dominated model). In the latter case, the maar size can be used to estimate the energy and depth of the largest explosion, which in turn allows estimation of the magma mass involved. This paper describes Lunar Crater maar (Nevada, USA) and tests the two models as explanations for the characteristics of the volcano, in particular the major-explosion dominated model. This model implies magma mass and supply rates that are unrealistic, and the tephra at the maar do not contain key features observed in the ejecta at large single-explosion craters. The incremental growth model seems most suitable based upon geological evidence. [ABSTRACT FROM AUTHOR]

At the Nevada Terawatt Facility we investigated the generation of a sheared plasma flow using conical wire arrays with an additional wire located on the axis of the pinch. The additional center wire generates axial current carrying plasma that serves as a target for the plasma accelerated from the outer wires, generating a sheared plasma flow which leads to the growth of the Kelvin-Helmholtz instability. These experiments were conducted on Zebra, a 2 TW pulse power device capable of delivering a 1 MA current in 100 ns. This paper will focus on the implosion dynamics that lead to shear flow and the development of the Kelvin Helmholtz instability. [ABSTRACT FROM AUTHOR]

Samples of rock, soil and seepage were collected from Yucca Mountain, USA, and analyzed for 36Cl/Cl ratios by accelerator mass spectrometry (AMS). Rock excavated from the Drill Hole Wash fault at repository horizon depths produced a ratio suggesting that small amounts of water with “bomb-pulse” 36Cl had percolated to that site over the past 50 years. Rock from four other sites within the exploratory studies facility did not yield bomb-pulse ratios. Ratios in the soil varied depending on depth and location, with some samples producing bomb-pulse signatures. Ratios for seep water were slightly elevated above the present cosmogenic background value. This paper also discusses results from a column study mimicking the passage of 36Cl through volcanic rock and from an experiment using bromide instead of chloride as a carrier in sample preparation for AMS. [ABSTRACT FROM AUTHOR]

The article presents abstracts of papers related to endoscopic surgery to be presented at the 2007 Scientific Session of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) in Las Vegas, Nevada, from April 18-22, 2007. They include "Laparoscopic Sleeve Gastrectomy for Weight Loss in Morbid Obesity," "Laparoscopic Management of Adjustable Gastric Band Slippage," and "Laparoscopic Duodenojejunostomy for Benign Duodenal Obstruction."

The article presents abstracts of papers related to endoscopic surgery to be presented at the 2007 Scientific Session of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) in Las Vegas, Nevada, from April 18-22, 2007. They include "The Use of Epidural Analgesia in Laparoscopic Colorectal Surgery," "Effect of Carbon Dioxide Pneumoperitoneum on Hepatic Tissue Perfusion," and "Laparoscopic Sigmoid Colectomy For Diverticulitis After Percutaneous Drainage."