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31.
Abstract: The Undergraduate Interagency Resource Teams at the White Mountain Research Station of the University of California were created in 1994 to support resource-agency mandates and academic research objectives by providing qualified students who can learn, apply, and improve research and agency monitoring protocols. Drawing from documented elements of other successful internship programs, we identified four basic components that we believe may enhance the potential success of the interns: (1) self-directed learning methodologies, (2) multidisciplinary approaches to science, (3) reflection on and documentation of intern learning, and (4) principles of a positive work environment, including teamwork, conflict resolution, and effective communication. During a 10-week summer session, the Interagency Resource Teams expose approximately 17 students to the professional worlds of natural resource agencies and research scientists. In this environment, we have also observed that the internship program not only exposes students to resource management careers but may also help bridge the gap between resource agency specialists and academic researchers.  相似文献   
32.
We examined the relationship between perceived workload and performance by evaluating the responses of police officers to 4 different draw-and-shoot tasks in a night field training exercise which was part of their regular training regimen. Sixty-two police officers volunteered to participate. Results demonstrated an associative trend among 3 tasks where shooting performance decreased and workload increased as the tasks became more complex. However, performance on 1 specific shooting task did not correlate with any of the other 3 tasks, and in this 1 exceptional case, insensitivities were observed in which workload increased but performance remained constant.  相似文献   
33.
Environmental effects on behavior have long been a focus of behavioral ecologists. Among the important drivers of behavior is predation environment, which can include the presence/absence of predators, differences in resource availability, and variation in individual density. Environments with predators are often more ecologically complex and “risky” than those without predators. Populations from these environments are sometimes more active and explorative than populations from low-risk, less complex environments. To date, most comparative studies of behavior are limited to within-species comparisons of populations from divergent environments, but neglect comparisons between species following speciation, thus limiting our understanding of post-speciation behavioral evolution. Brachyrhaphis fishes provide an ideal system for studying correlations between divergent environments and behavior within and between species. Here, we test for differences in two behavioral traits—activity and exploration —between sister species Brachyrhaphis roseni and Brachyrhaphis terrabensis that occur in divergent predation environments. Species differed in activity and exploration, with higher activity and exploration levels in populations that co-occur with predators. Furthermore, we found drainage-by-species interactions, indicating that the nature of divergence varied geographically. Using the recently developed phenotypic trajectory analysis (PTA), we quantified this difference and found that, while the geographically isolated populations of sister species tended to evolve in parallel, the magnitude of divergence between species differed between drainages. Our results highlight the utility of PTA for multivariate behavioral data and corroborate past predictions that complex and risky environments are correlated with increased activity and exploration levels and that divergence continues post-speciation.  相似文献   
34.
On separate days, 6 highly trained participants performed psychomotor tests while breathing for 60 min 3 carbon dioxide (CO(2)) mixtures (room air, 3% CO(2), or 4% CO(2)) prior to, between, and following two 15-min treadmill exercise bouts (70% VO(2)(max)). Each individual was extensively practiced (at least 4 days) before testing began, and both gas conditions and order of tasks were counterbalanced. Results showed physiological reactions and work-related psychomotor effects, but no effects of gas concentration on addition, multiplication, grammatical reasoning, or dynamic postural balance. These findings help define behavioral toxicity levels and support a re-evaluation of existing standards for the maximum allowable concentrations (also emergency and continuous exposure guidance levels) of CO(2). This research explored the selection of psychometric instruments of sufficient sensitivity and reliability to detect subtle changes in performance caused by exposure to low levels of environmental stress, in this case differential levels of CO(2) in the inspired air.  相似文献   
35.
ABSTRACT: Studies on the responses of zooplankton to dredging are summarized and discussed. Design criteria for studies intended for impact assessment require careful consideration of sampling due to the highly variable spatial and temporal distributions of zooplankton. It is suggested that ocean dominated systems present different research requirements than those estuarine regions which have endemic zooplankton populations.  相似文献   
36.
将时间-活动模式与微环境空气污染物监测相结合估计儿童个体NOx暴露水平. 分别在北京和青岛两市各选择3所学校监测校园环境污染物,并在每个学校选择10名儿童监测其家庭居室空气中ρ(NOx)及个体24 h NOx暴露水平,同时收集其时间-活动信息,采用时间-活动模式估计儿童的个体暴露水平. 交通工具中的NOx暴露水平可通过校门口空气中ρ(NOx)和交通工具的污染水平系数(λ)估计.结果表明:利用时间-活动模式模拟的儿童个体24 h NOx暴露水平为0.041 mg/m3,与调整后的个体暴露实测水平相关性较好(R0.785,P<0.01),差值为(-0.002 6±0.013 0) mg/m3,二者的差异无统计学意义 (t0.139,P>0.05).表明采用时间-活动模式与微环境空气质量监测结果相结合方法估计的儿童NOx暴露水平与个体实际暴露水平一致.   相似文献   
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