Substance use among lesbian, gay, and bisexual young people: the role of neighborhood, school, and family

Disparities exist between lesbian, gay, and bisexual (LGB) young people and their non-LGB peers, with LGB young people continuing to use alcohol and other drugs into emerging adulthood at higher rates than non-LGB young persons.1–6 Our analyses were conducted with data from two nationally representative studies in the US, the National Longitudinal Study of Adolescent to Adult Health (Add Health) and the National Longitudinal Survey of Youth 1997 (NLSY|97). Using Add Health data, a marginal structural model and structural equation model were used to examine the effect of neighborhood economic advantage (N = 15,101 non-LGB and 5,031 LGB young persons) and neighborhood cohesion (N = 15,097 non-LGB and 5,004 LGB young persons) on the occurrence of alcohol and cannabis use disorders and alcohol use disorder symptoms. With the NLSY|97, logistic regression models assessed the association between parental support and binge drinking among LGB young persons (N = 302 LGB young persons), and whether living in a state with supportive LGB policies modified this association. We found living in a neighborhood with higher levels of neighborhood economic advantage was associated with a lower risk of alcohol [0.81 (0.72-0.90)] and cannabis use disorders [0.88 (075-1.04)]. Neighborhood advantage had a stronger protective effect for LGB [0.75 (0.58-0.96)] than non-LGB [0.99 (0.81-1.21)] young people when examining cannabis use disorders. Higher levels of neighborhood cohesion were mediated by family and school cohesion and were inversely associated with alcohol use disorder symptoms, with a stronger total effect among LGB [-0.05 (-0.10 - -0.01)] than non-LGB [-0.03 (-0.06 – 0.00)] young persons. Higher parental support was inversely associated with binge drinking among LGB young people [0.85 (0.51-1.43)] with a trend toward a more protective effect among LGB persons living in states with supportive LGB-related policies. Our findings contribute to the published literature by extending the research on neighborhood context and substance use outcomes to an LGB population. Building state-level and neighborhood assets has the potential to reduce substance use and abuse among LGB young persons

Multi-Level Collaborative Management of Colorado's Instream Flow Program

Managing water in a way that maintains human welfare and meets the demands of surrounding ecosystems involves a variety of stakeholders, diverse sets of values and, subsequently, a wide range of competing uses. Since the early 1970s, instream flow uses, or water intentionally kept in a stream for the purpose of preserving or improving the natural environment of that stream, have become an increasing part of the conversation about water allocation in the West. The management of Colorado water involves numerous values and interests, many of which are in direct conflict to each other. As such, it is often difficult to translate those competing interests into a real world management regime in which all values are represented. Collaborative management, a process of identifying and developing general programs, specific projects, and the subsequent institutional structures to implement those projects in the real world (Gerlach, 1995), offers a flexible, holistic, and balanced approach to water management and is particularly useful when considering instream flow protection in Colorado. The goal of the following analysis is to better understand the institutional arrangements that surround the implementation of Colorado’s ISF Program in order to better explain whether the role of collaborative management in Colorado water governance has been and will be a successful approach to protecting ISF in Colorado

The Relationship Between Crystal Structure and Methyl and \u3ci\u3et\u3c/i\u3e-Butyl Group Dynamics in van der Waals Organic Solids

We report x-ray diffractometry in a single crystal of 2-t-butyl-4-methylphenol (TMP) and low-frequency solid state nuclear magnetic resonance (NMR) proton relaxometry in a polycrystalline sample of TMP. The x-ray data show TMP to have a monoclinic, P2(1)/c, structure with eight molecules per unit cell and two crystallographically inequivalent t-butyl group (C(CH3)(3)) sites. The proton spin-lattice relaxation rates were measured between 90 and 310 K at NMR frequencies of 8.50, 22.5, and 53.0 MHz. The relaxometry data is fitted with two models characterizing the dynamics of the t-butyl groups and their constituent methyl groups, both of which are consistent with the determined x-ray structure. In addition to presenting results for TMP, we review previously reported x-ray diffractometry and low-frequency NMR relaxometry in two other van der Waals solids which have a simpler structure. In both cases, a unique model for the reorientational dynamics was found. Finally, we review a similar previously reported analysis in a van der Waals solid with a very complex structure in which case fitting the NMR relaxometry requires very many parameters and serves mainly as a flag for a careful x-ray diffraction study

Similarity Properties and Scaling Laws of Radiation Hydrodynamic Flows in Laboratory Astrophysics

The spectacular recent development of modern high-energy density laboratory facilities which concentrate more and more energy in millimetric volumes allows the astrophysical community to reproduce and to explore, in millimeter-scale targets and during very short times, astrophysical phenomena where radiation and matter are strongly coupled. The astrophysical relevance of these experiments can be checked from the similarity properties and especially scaling laws establishment, which constitutes the keystone of laboratory astrophysics. From the radiating optically thin regime to the so-called optically thick radiative pressure regime, we present in this paper, for the first time, a complete analysis of the main radiating regimes that we encountered in laboratory astrophysics with the same formalism based on the Lie-group theory. The use of the Lie group method appears as systematic which allows to construct easily and orderly the scaling laws of a given problem. This powerful tool permits to unify the recent major advances on scaling laws and to identify new similarity concepts that we discuss in this paper and which opens important applications for the present and the future laboratory astrophysics experiments. All these results enable to demonstrate theoretically that astrophysical phenomena in such radiating regimes can be explored experimentally thanks to powerful facilities. Consequently the results presented here are a fundamental tool for the high-energy density laboratory astrophysics community in order to quantify the astrophysics relevance and justify laser experiments. Moreover, relying on the Lie-group theory, this paper constitutes the starting point of any analysis of the self-similar dynamics of radiating fluids.Comment: Astrophys. J. accepte

Simulating radiative shocks in nozzle shock tubes

We use the recently developed Center for Radiative Shock Hydrodynamics (CRASH) code to numerically simulate laser-driven radiative shock experiments. These shocks are launched by an ablated beryllium disk and are driven down xenon-filled plastic tubes. The simulations are initialized by the two-dimensional version of the Lagrangian Hyades code which is used to evaluate the laser energy deposition during the first 1.1ns. The later times are calculated with the CRASH code. This code solves for the multi-material hydrodynamics with separate electron and ion temperatures on an Eulerian block-adaptive-mesh and includes a multi-group flux-limited radiation diffusion and electron thermal heat conduction. The goal of the present paper is to demonstrate the capability to simulate radiative shocks of essentially three-dimensional experimental configurations, such as circular and elliptical nozzles. We show that the compound shock structure of the primary and wall shock is captured and verify that the shock properties are consistent with order-of-magnitude estimates. The produced synthetic radiographs can be used for comparison with future nozzle experiments at high-energy-density laser facilities.Comment: submitted to High Energy Density Physic