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1.

The main objective of this study was to determine how stream salamander assemblages and species respond to varying levels of impervious surface cover within Maryland’s Piedmont physiographic province. We sampled stream salamanders in 21 first-order streams located in watersheds representing a range of impervious surface cover (0–24 %) across the northeastern part of Maryland’s Piedmont region. Habitat data, including stream substrate and riparian characteristics, were measured at each site. Eurycea bislineata was the predominant species of stream salamander encountered during this study (> 99 % of individuals) and most of these individuals were larvae (> 92 %). Consequently, statistical analysis was limited to E. bislineata larvae. We were unable to detect a difference in E. bislineata abundances or body mass index’s among varying levels of impervious surface cover % or any individual site habitat variables alone. These results suggest that in smaller watersheds within the Piedmont of Maryland, local habitat variables, in conjunction with land use variables, are necessary in determining the abundance and body mass index of E. bislineata larvae populations. This study makes a strong case for halting the over-simplification of the relationship between urbanization and the presence/abundance of stream salamanders.

  相似文献   
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The most extensively studied influence on adolescent conduct problem behaviors is peers, and the literature points to genetics as one source of individual differences in peer influence. The purpose of this study was to test the hypothesis that an environmental sensitivity genetic index comprised of DRD4, 5‐HTTLPR, and GABRA2 variation would moderate the association between peer and adolescent conduct problems. Latent growth modeling was applied to PROSPER project longitudinal data from adolescents and their peers. Results showed the hypothesis was supported; adolescents with more copies of putative sensitivity alleles were more strongly influenced by their peers. The interaction form was consistent with differential susceptibility in follow‐up analyses. Strengths and weaknesses of genetic aggregates for sensitivity research are discussed.  相似文献   
3.
The amount of radon in natural gas varies with its source. Little has been published about the radon from shale gas to date, making estimates of its impact on radon‐induced lung cancer speculative. We measured radon in natural gas pipelines carrying gas from the Marcellus Shale in Pennsylvania and West Virginia. Radon concentrations ranged from 1,520 to 2,750 Bq/m3 (41–74 pCi/L), and the throughput‐weighted average was 1,983 Bq/m3 (54 pCi/L). Potential radon exposure due to the use of Marcellus Shale gas for cooking and space heating using vent‐free heaters or gas ranges in northeastern U.S. homes and apartments was assessed. Though the measured radon concentrations are higher than what has been previously reported, it is unlikely that exposure from natural gas cooking would exceed 1.2 Bq/m3 (<1% of the U.S. Environmental Protection Agency's action level). Using worst‐case assumptions, we estimate the excess lifetime (70 years) lung cancer risk associated with cooking to be 1.8×10?4 (interval spanning 95% of simulation results: 8.5×10?5, 3.4×10?4). The risk profile for supplemental heating with unvented gas appliances is similar. Individuals using unvented gas appliances to provide primary heating may face lifetime risks as high as 3.9×10?3. Under current housing stock and gas consumption assumptions, expected levels of residential radon exposure due to unvented combustion of Marcellus Shale natural gas in the Northeast United States do not result in a detectable change in the lung cancer death rates.  相似文献   
4.
Public Organization Review - Budget cuts in public sector organizations create additional strain for employees, often contributing to uncertainty, rumors, and low morale. This study examines the...  相似文献   
5.
The opportunity to live authentically is critical for the well-being of transgender individuals. For many this requires accessing transition-related services. Current knowledge of transition-related care is limited. This study aims to elucidate experiences and needs of transgender individuals (N = 65) related to (a) therapeutic support, (b) medical care, and (c) aspects of living authentically in order to inform the development and delivery of trans-affirmative services. Findings reveal challenges accessing health care providers with trans-specific competency; gaps between critical aspects of transition-related care and receipt of services; and heterogeneity of experiences and needs. Recommendations for improving transgender-affirmative services are provided.  相似文献   
6.
The purpose of the present study was to determine the effectiveness of an ergonomic and behavioral safety intervention for improving participants' safe typing postures in a library office setting. A single-subject multiple baseline design across five participants was employed to evaluate the effects of the four independent variables (workstation adjustment, equipment trial (rollermouse mouse alternative), peer observations, and graphic feedback). Six participant postures were observed repeatedly while participants worked at their workstations throughout the study. Each of the interventions resulted in improvements in safety for more than one posture compared to the previous phase. Results of the study indicate that a comprehensive ergonomic program that includes a workstation adjustment and a behavioral safety approach may be helpful to produce maximum improvements in employees' safe ergonomic postures.  相似文献   
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This article uses ethnographic methods to explore how peer support and community involvement influence the mental health and well-being of transgender (or, trans) people in the southeastern United States. The study builds on existing research that suggests that trans community involvement and peer support among trans people enhance mental health experiences and moderate the effects of stigma and discrimination on health outcomes. Through qualitative analysis of 158 hours of participant observation and 33 in-depth interviews with members of a trans community organization in the U.S. Southeast, this paper identifies three key processes through which peer support and community involvement enhance the mental health and well-being of trans people: (1) the normalization of trans identities and experiences; (2) the creation of a social support network; and (3) the empowerment of trans people.  相似文献   
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Because all career choices are about future actions, time is an important contextual variable in social cognitive career choice ( Hesketh, 2000 ). However, there is a dearth of research examining the effect of time. The authors examined how temporal distance to career entry influences the perceived importance of self‐efficacy and outcome expectations concerning a career pursuit. They also examined the moderating effects of perceived support and barriers, as well as country. The participants were college students in the United States (n= 180) and in South Korea (n= 215). The results of hierarchical regression analyses did not show main effects of time, but a 3‐way interaction indicated the complex interplay of time and other contextual variables. Implications for career counseling and future research are discussed.  相似文献   
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