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2025 Nevada High School Youth Risk Behavior Survey
No full textNevada Center for Surveys, Evaluation, and Statistics (CSES) survey about health behavior. It has been developed for Nevada high school students to tell us what they do that may affect their health. The information they give will be used to improve health education for young people. If you have any questions or comments please contact https://www.unr.edu/public-health/research-activities/nevada-youth-risk-behavior-surve
2023 Nevada Middle School Youth Risk Behavior Survey (YRBS): Adverse Childhood Experiences (ACEs) Special Report
No full textThis surveillance project was partially supported by a grant from the Centers for Disease Control and Prevention (CDC-PS18-1807). Supplemental funding was also provided by the Nevada Division of Public and Behavioral Health
Verification and Validation of Magnetohydrodynamics Simulations of Electrically Exploded Conductors
No full textDense Z-pinches, magnetically-driven flyer plates, and electrically exploded wires and foils all take advantage of the extreme Lorentz forces and/or Ohmic heating generated by intense electrical current pulses through an initially solid conductor. Magnetohydrodynamics (MHD) simulations are used to interpret results of these pulsed power systems and design targets for future experiments. Formal testing of the numerical codes is necessary and broken into two categories: verification and validation. Verification tests how precisely a code solves the physics model implemented in it while validation describes how accurate the physics model is at capturing the system being modeled.MHD simulations of electrically exploded aluminum and copper rods demonstrate a novel technique to validate equations of state (EOS) for rapidly Ohmic-heated conductors. The single-fluid, resistive MHD code FLAG was used to simulate the phase transitions and bulk hydrodynamic motion of these conductors. The balance of internal and magnetic forces at the conductor-insulator interface drives the metal along the vaporization phase boundary. Variations between critical points and vaporization curves in existing models predict differing densities/temperatures in MHD simulations for these models. The inclusion of Maxwell constructs in the liquid/vapor biphase region of the EOS caused the rod surface to vaporize earlier in time than unmodified tables with Van der Waals (VdW) loops. Fully resolved 1D calculations did not heat up enough for the surface to exit the liquid/vapor biphase--suggesting 2D/3D effects are significant for plasma formation. Experimental velocimetry measurements were used to validate the location of the vaporization curve in existing EOS models and differentiate between the vapor dome treatments. Dielectric coatings applied to the metal surface restricted the conductor's expansion and diverted the metal into the warm dense matter regime
Complicating Visibility: Celebrating Disabled and Transgender Identity Through Visual Art
No full textI live in a body with bones that ache, a heart that beats twice as fast as everyone else's, and fingertips that go numb. Most of the time my body does not feel like mine. Gender dysphoria, coupled with conditions that impact my vision leave me looking down at my body as if it is someone else's. This is not a tragedy; it is simply a fact of my existence. Queer and disabled people are often viewed as unnatural. I respond to this in my work through using natural materials and imagery of the outdoors. My sculptures, photography, and installations reposition the queer and disabled body as being synonymous with nature. Outdoor spaces can be inaccessible, and it is important for me to reclaim my body's relationship to the environment. I introduce an alternate trans-disabled reality by utilizing transgender and disability-specific medical objects that are commonly disposed of or hidden away. Through the overlaying of photographs on top of hospital fluorescent lights, weaving flowers in between bandages, and suspending images of the sky within IV bags, I propose a world in which bodies like mine are cared for and celebrated
Evaluation of PFAS in Environmental Solids: Retention Devices and a Screening Method
No full textPer- and polyfluoroalkyl substances (PFAS) present a threat to global ecosystems and human health due to their ubiquitous use and unique physicochemical properties. Through direct and indirect emissions, PFAS can end up in soil which serves as both a reservoir and a source of further contamination. Thus, there is a need to find ways to limit PFAS spread and quickly identify contaminated sites.To address this first need, environmental and bench-scale tests were conducted to investigate PFAS sorption to sediment retention devices and to evaluate their potential to limit PFAS spread. Devices such as straw wattle and SiltSoxx are commonly used to filter stormwater and may already be environmentally exposed to PFAS. Urban fires like the 2018 Camp Fire in Paradise, CA, are potential sources of PFAS contamination as PFAS-containing household objects burn and release PFAS; sediment retention devices deployed after these disasters are likely exposed to PFAS in stormwater runoff. To determine if PFAS sorption occurs on these devices, samples of SiltSoxx and straw wattle deployed after the Camp Fire were analyzed with combustion ion chromatography for total fluorine (TF) and extracted organic fluorine (EOF). While no correlation between TF and EOF was found, EOF concentrations of both SiltSoxx and straw wattle were higher than typical background concentrations found by others, indicating that PFAS sorption is likely to have occurred. Kinetics tests were used to establish the sorption equilibrium time and partition coefficients were calculated to compare sorption capacity for each material across a range of spiked DOC and PFOA concentrations. DOC was found to facilitate fluorine sorption to both materials. SiltSoxx in the presence of high and low DOC had higher partition coefficients than straw wattle. SiltSoxx also had higher average sorbed concentrations than straw wattle. It was thus concluded that SiltSoxx is the better choice for deployment and limiting PFAS spread after urban fires. In addition to limiting PFAS spread, there is also a need to identify contaminated sites. Current analytical methods, due to tradeoffs between inclusivity and selectivity and limitations from sample characteristics, are an obstacle to easy identification of contaminated sites. Agencies that send out samples to analytical laboratories using these methods are further subject to long delays and high costs. To facilitate identification of contaminated sites, a screening method involving optimized extraction, combustion, and Fourier Transform Infrared (FTIR) analysis was developed. As PFAS combustion breakdown products form SiF4, FTIR analysis provides a novel way to assess PFAS concentration from SiF4 maximum peak area. Calibration curves relating concentrations of GenX, PFOA, and PFOS to SiF4 maximum peak area were created, and method detection limits and limits of quantitation were determined. The final method detection limits�"13.82, 13.18, and 15.31 µg F/g for GenX, PFOA, and PFOS respectively�"are environmentally relevant since contaminated sites regularly have concentrations that exceed these limits. Therefore, this screening method is applicable to environmental testing and can be used to quickly identify samples that are contaminated and in need of further analysis
Factors Controlling the Extent and Location of Cumulus Convection over the Sierras de Córdoba
Get PDFWe examine the factors controlling the location and extent of cumuli over the Sierras de Córdoba (SDC) of Argentina during the Cloud, Aerosol, and Complex Terrain Interactions (CACTI) field campaign. While it is well understood that mountains are effective at producing cloud cover via thermal and mechanical lifting of the air to saturation, it is less well understood what factors create nuanced differences in the location of cloud initiation and subsequent development. For example, satellite observations reveal that some days produce clouds directly over the SDC ridge crest, whereas others produce clouds displaced east (and sometimes west) from the SDC ridge. We hypothesize that these variations in cloud location can be explained by variations in the interactions amongst, (1) thermally generated upslope flow layers, (2) background westerly winds near the ridge crest, and (3) mountain wave processes. To investigate these interactions we combine satellite, radar velocity, radar reflectivity, and stereographic/photogrammetric analyses of mountain flows and their resulting cloud cover. We also use thermodynamic analyses to understand what air is being lifted to produce the observed clouds and to what extent the SDC crest is immersed in boundary layer air
Exteroceptive and Interoceptive Stimuli in the Contextual Control of Behavior by Circadian Rhythm in Mice
Get PDFBehavior analysis is the study of how the behavior of individual organisms is related to their contexts. Context is the field/configuration of all stimulus objects/events that are interrelated with/affect an individual organism's behavior at any given moment. The stimulus objects/events that are interrelated with organisms' behavior may include both exteroceptive stimuli (stimulation arising from objects/events occurring outside of the organism's body) and interoceptive stimuli (stimulation from organisms' own bodies). Circadian rhythm (patterns of physiological activity and behavior organized around approximately 24-h cycles) is an important factor in determining behavior, and it is comprised of both exteroceptive and interoceptive stimulus factors. This study used renewal/reinstatement preparations to 1) determine if circadian rhythm could serve as a context for learning and 2) characterize the relative contributions of exteroceptive and interoceptive stimuli in the contextual control of behavior by circadian rhythm. An operant response was acquired through reinforcement at one point in the circadian cycle and then extinguished at a different point in the cycle. Following extinction sessions, the colony room light/dark cycle was manipulated for one group (i.e., "Shift" group) and not for the other group (i.e., "No Shift" group). Both groups exhibited renewal relative to the last extinction session when returned to their clock time acquisition contexts. As the amount of renewal observed was approximately equivalent between groups, the interoceptive stimuli presumed to be associated with circadian rhythm can be an important part of context for associative learning
Intelligent Transportation Systems and Virtual Reality as Technology Accelerators for Smart Infrastructure Monitoring
No full textThis work extends the application of intelligent transportation systems (ITS) to the field of structural health monitoring (SHM) for bridge infrastructures and develops a virtual reality (VR) platform as a technology accelerator. In the proposed SHM method, video recordings of traffic are captured using traffic cameras and processed using a combination of YOLO and Deep SORT models, along with projective mapping, to extract the time history of vehicle tire locations. This step, referred to as traffic tracking, predicts the points at which traffic loads excite the bridge. This information is integrated with the bridge's vibration response and the finite element (FE) model to develop a digital twin of the bridge. The necessary models for the traffic tracking component are trained using Google Open Images and tested in a VR environment that simulates traffic on a roadway with installed cameras. Utilizing VR instead of real-world tests significantly accelerates technology development. After achieving promising results in the VR environment, the prototype of the proposed technology has been developed and deployed on a real-world bridge
Model-based Exploration of Chemical Absorption and Metabolism Kinetics in the Human Gastrointestinal Tract
No full textEvaluating the oral bioavailability (Fbio) of ingested chemicals in the human gastrointestinal tract is pivotal for assessing chemical concentrations in the human systemic circulation and informing potential toxicological impacts, especially in the era of �"new approach methods" targeting chemical screening and prioritization. This dissertation advances the understanding and predictions of chemicals' Fbio from the perspectives of chemical properties and mass-balance modeling. First, the rate at which a chemical can transport across membranes is an important indicator of how fast it can be absorbed by humans. Therefore, the possibility and challenge of adapting one of the popular transmembrane permeability models in the pharmaceutical industry, parallel artificial membrane permeability assay (PAMPA), for use with chemicals of environmental concern (CEC) is explored. The results underscore the importance of considering chemical properties when applying the current design of PAMPA to chemicals of environmental concern due to the differences in the physiochemical properties between CECs and pharmaceuticals. In addition, pre-absorption metabolism can potentially play an important role in the Fbio of CECs. Therefore, a physiological-based toxicokinetic (PBTK) model is built to understand the potential of chemicals to undergo pre-systemic metabolism, especially in the human gut lumen. The results show that gut lumen metabolism can significantly reduce the Fbio of CECs, for instance, by more than 80% for di(2-ethylhexyl)phthalate. Therefore, when assessing the Fbio of CECs, it is crucial to consider gut lumen metabolism. Additionally, the results show that the gut absorption rate (kabs) or fraction absorbed in the gut (Fabs) can be an important factor not only affecting Fbio by controlling the rate of absorption but also affecting gut lumen metabolism. Therefore, I built a model to understand Fabs from the perspectives of both transmembrane permeability and partition coefficients. The results show that permeability and partition coefficients interactively control Fabs. Consequently, when assessing the Fabs of CECs, both chemical properties must be considered