Characterization and extent of expansive soils in the Las Vegas Valley

Expansive soils have been documented in the Las Vegas Valley for many years; however, the extent of these soils horizontally and vertically was relatively unknown. This study investigates the extent and expansivity of soils in the Las Vegas Valley. It is an attempt to present an empirical model predicting areas where expansive soils may be encountered. A correlation between swell test results and plasticity index was evaluated for two datasets, and results compare favorably with relationships established for other areas. Analyses were conducted to evaluate correlations between expansion potential and topographic slope, soil classification, and locations of subsidence-related faults and earth fissures. Results show that expansion potential generally increases with decreasing slope, finer grain-size and increasing plasticity. Over ninety-four percent by length of mapped subsidence-related faults are located within areas having some expansion potential. Eighty-eight percent of earth fissures are found in areas exhibiting moderate to critical expansion

Fault Slip and Exhumation History of the Willard Thrust Sheet, Sevier Fold‐Thrust Belt, Utah: Relations to Wedge Propagation, Hinterland Uplift, and Foreland Basin Sedimentation

Zircon (U‐Th)/He (ZHe) and zircon fission track thermochronometric data for 47 samples spanning the areally extensive Willard thrust sheet within the western part of the Sevier fold‐thrust belt record enhanced cooling and exhumation during major thrust slip spanning approximately 125–90 Ma. ZHe and zircon fission track age‐paleodepth patterns along structural transects and age‐distance relations along stratigraphic‐parallel traverses, combined with thermo‐kinematic modeling, constrain the fault slip history, with estimated slip rates of ~1 km/Myr from 125 to 105 Ma, increasing to ~3 km/Myr from 105 to 92 Ma, and then decreasing as major slip was transferred onto eastern thrusts. Exhumation was concentrated during motion up thrust ramps with estimated erosion rates of ~0.1 to 0.3 km/Myr. Local cooling ages of approximately 160–150 Ma may record a period of regional erosion, or alternatively an early phase of limited... (see full abstract in article)

Runner Identity and Sponsorship: Evaluating the Rock ‘n’ Roll Marathon

The economic value of participation sport has been reported to eclipse spectator sport significantly. However, scholars have acknowledged the relative lack of research on this important segment of the sport market. The purpose of this study was to analyze the relationship between runner identity and race sponsor effectiveness. Surveys were sent to participants in the Las Vegas Rock ‘n’ Roll Marathon. The survey was constructed to measure runner identity, and sponsor effectiveness as interpreted through rates of recognition, recall and purchase intention. Runners were divided into three groups based on their runner identity score. Of the predictive variables, only runner identity was a significant predictor of sponsor recognition and recall and one of two significant variables for purchase intention. The current study established runner identity as a unique construct and shows how runner identity is tied to measures that can be used by race organizers to attract or retain sponsors

Semi-active control techniques for shock isolation

In this thesis the problem of control of semi-active devices (MR damper, MR elastomer) for shock isolation systems are considered. Semi-active control systems combine the best features of both the passive and active control systems, offering the reliability of passive devices, yet maintaining the versatility and adaptability of fully active devices. First the question of stability and control of a two degree-of-freedom magnetorheological (MR) fluid damper shock isolation system is considered. It is shown that for any arbitrarily time varying input current, the system is absolutely stable. This explains the shock isolation capability of the MR damper system even with control laws clamped in an ad hock way to limit the control magnitude. Then a nonlinear inverse (feedback linearizing) control law and a nonlinear suboptimal control law based on the state-dependent Riccati equation (SDRE) method are designed for the shock isolation of the payload mass. For the inverse control law derivation, the inertial position of the payload is chosen as the controlled output variable. For the design via the SDRE method, constraint on the input current is introduced and a quadratic performance index is chosen for minimization. It is shown that in the closed-loop system the inverse and suboptimal control laws are effective in shock isolation of the payload mass; Secondly, the mathematical modeling and predictive control of a magnetorheological fluid damper system is considered. (Abstract shortened by UMI.)

Development of a safety analysis and an intersection infrastructure system

GIS and GPS technologies have found immense applications in the field of transportation engineering. Different features related to transportation safety are inventoried using these technologies. The databases so created serve as main source for safety analyses, decision making and reporting. Many different analyses tools are available to assist engineers, planners and policy makers in the process of improving transportation safety. GIS-based analyses tools provide tabular and graphic display, thereby expediting the analyses process and improving the spatial understanDing The advantages of such tools increase if they can be provided on the World Wide Web. One such software system that offers online analyses tool is the ArcIMS; This research is aimed at developing a GIS-based tool to inventory signalized intersection attributes. In addition, an internet based analyses system that utilizes the signalized intersection database and the crash database is developed. The tools provide number of choices to perform user-defined queries to generate specific results. The system is developed using Visual Basic .Net programming language. The applications developed here are demonstrated with the data available for the Las Vegas metropolitan area

The Persistent Southern Disadvantage in Us Early Life Mortality, 1965‒2014

Background: Recent studies of US adult mortality demonstrate a growing disadvantage among southern states. Few studies have examined long-term trends and geographic patterns in US early life (ages 1 to 24) mortality, ages at which key risk factors and causes of death are quite different than among adults. Objective: This article examines trends and variations in early life mortality rates across US states and census divisions. We assess whether those variations have changed over a 50-year time period and which causes of death contribute to contemporary geographic disparities. Methods: We calculate all-cause and cause-specific death rates using death certificate data from the Multiple Cause of Death files, combining public-use files from 1965‒2004 and restricted data with state geographic identifiers from 2005‒2014. State population (denominator) data come from US decennial censuses or intercensal estimates. Results: Results demonstrate a persistent mortality disadvantage for young people (ages 1 to 24) living in southern states over the last 50 years, particularly those located in the East South Central and West South Central divisions. Motor vehicle accidents and homicide by firearm account for most of the contemporary southern disadvantage in US early life mortality. Contribution: Our results illustrate that US children and youth living in the southern United States have long suffered from higher levels of mortality than children and youth living in other parts of the country. Our findings also suggest the contemporary southern disadvantage in US early life mortality could potentially be reduced with state-level policies designed to prevent deaths involving motor vehicles and firearms

A small step closer to the Holy Grail of DNA vaccines: undisputed clinical benefit in humans

A report of the DNA Vaccines 2008 meeting, Las Vegas, Nevada, USA, 9-11 December 2008

Characterization of stage VI petrocalcic horizons: S Nevada and NW Arizona

Highly indurated petrocalcic soil horizons are records of paleoclimate, and past geomorphic and pedogenic processes that have occurred in arid and semi-arid regions. This research used geomorphic mapping, profile descriptions and sampling, and micromorphological and chemical analyses to identify the geomorphic and pedogenic processes that contributed to the development of stage II-VI petrocalcic horizons at Mormon Mesa, Nevada. Soil pisoliths are described as stage II soil pendants and nodules incorporated into the indurated horizons as rotated soil pendants with pendant lamina on their undersides and as fragments of petrocalcic materials with pendant lamina on their undersides. These soil features record pedogenic responses to oscillations in climate from the early Pliocene to Holocene. The events that created pisolith features at Mormon Mesa include the exposure of the upper portions of the horizons, erosion, fragmentation, and incorporation of these fragments into eolian deposits at the surface. Chemical and mineralogical processes that occur within these highly indurated horizons include the dissolution of grains and formation of pedogenic minerals such as sepiolite, palygorskite, and barite. Pedogenic barite precipitated in areas of increased microporosity that include root pores, cracks, and amid fibers of fibrous silicate clays. Barium from dust leached into the profile during precipitation events and combined with sulfate to precipitate barite in the areas of microporosity. The chemical and mineralogical processes that have occurred in the Mormon Mesa soil are evidence that it is not a closed system. In western Arizona, strong stage V-VI petrocalcic horizons cap Neogene sediments of the Colorado River. Geomorphic mapping was used to examine the sediments that record the pre- and post-inception of the river system. Interpretation of these sediments and the soils that cap them is important for our understanding of the timing of river incision in the region. The work detailed in this dissertation is important for the overall understanding of geomorphic and climatic factors that affect the development of late-stage petrocalcic horizons. This research provides the necessary groundwork for future dating applications and contributes to our knowledge of the physical and chemical processes taking place within these unique soils

Mapping Nevada\u27s Dental Workforce

Access to care is a concern at the forefront of public health. Due to socioeconomic and geopolitical pressures, the distribution of healthcare providers across a population often does not coincide with the demand for healthcare in a specific geographic area. Rural areas typically do not have enough providers and urban areas typically have too many. This stark reality underscores an inherent inefficiency in the allocation of healthcare resources and is a discrepancy that must be addressed by state-sponsored institutions and programs. From a public health perspective, the problem of insufficient or lack of access to care is the greater of the two problems. Rural residents that require care face additional challenges that the urban counterpart does not readily encounter. They include the sheer lack of qualified providers that can address their specific concerns, lack of interdisciplinary care that is required for more complex medical and dental conditions, and higher costs associated with receiving this care, which may come from high transportation costs, long waiting time and long commutes. These barriers place unneeded pressures on the care seeker and can ultimately lead to aggravation of the medical or dental condition itself and poorer patient outcomes. Geographic information system (GIS) mapping of the state’s general dentists and clinical specialists revealed an uneven per capita distribution of dental providers between the 17 counties in the state of Nevada as well as between the 55 zip codes of the Las Vegas Valley. The study found that 0.6% of Nevadan residents in the state lived beyond a 30-mile radius of a dental office and 1.7% of Nevada residents in the state lived beyond a 30-mile radius of a Medicaid-accepting dental office, with virtually all such residents living in a rural county. Moreover, the study found zip codes with a larger ratio of Medicaid-accepting dental offices in the Las Vegas Valley were associated with a greater percentage of children, minorities, and Hispanics in the population, as well as a lower median household income