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31.
The present paper examines the role of several demographic indicators on stated hurricane evacuation thresholds, or the lowest category storm for which participants indicated they would evacuate, for mandatory and voluntary orders. Quantitative analyses reveal that race was significantly associated with a lower stated evacuation threshold in both the bivariate and multivariate models and that previous refusal to comply with evacuation orders was associated with higher stated evacuation thresholds. Qualitative analyses reveal two key findings: (1) wind is perceived as more dangerous than water (rain and storm surge) associated with hurricanes; (2) traffic concerns were the most frequently cited reason listed for possible refusal to comply with evacuation orders. Implications of the findings include the value of future evaluations of race and trust, storm characteristics and threat perception, and other practical considerations for improving evacuation compliance such as the amelioration of traffic concerns. Findings also lead to the discussion of the social complexities of race and hurricane vulnerability as a key finding.  相似文献   
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The field of engineering is changing rapidly as the growing global population puts added demands on the earth's resources: engineering decisions must now account for limitations in materials and energy as well as the need to reduce discharges of wastes. This means educators must revise courses and curricula so engineering graduates are prepared for the new challenges as practicing engineers. The Center for Sustainable Engineering has been established to help faculty members accommodate such changes through workshops and new educational materials, including a free access website with peer-reviewed materials.  相似文献   
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Summary In the current push for wildland preservation it is imperative to consider the inherent value of wilderness as a medium for improving psychological health. As Fritz Perls and other Gestalt psychologists have pointed out, we are living in an increasingly complex social structure which is causing us to lose touch with our ‘inner voice’—the voice that Perls claimed could tell us how to maintain organismic health and balance, if only we paid attention to it. He emphasized the need for an individual to become self-aware and self-responsible in order to reach psychological maturity (internal versus external support). However learning and developing self-awareness need not occur in a therapeutic setting alone. The process of personal growth may be greatly expedited by spending time in a wilderness setting. Environmentalists have long known about the healing powers of nature. From Thoreau to Abbey, they have pointed out the unique qualities of wilderness—simplicity and impartiality—which, in contrast to a complex, value-governed society, make it an ideal setting for self-exploration and understanding. People who experience the wilderness can return empowered to act as responsible, aware human beings, in a currently unhealthy, dehumanizing society. Ms. Suttie is a native of Northern California where the natural beauty of rugged coastline and wooded hills impressed upon her the importance of preserving the environment. Ms. Suttie completed her undergraduate degree in Biochemistry-Molecular Biology at the University of California, Santa Barbara (1981) and is presently involved in the master of Arts programme in Confluent Education, also at UCSB. She is studying under the direction of Dr George Brow, a noted Gestalt therapist. She hopes to combine the insights of the Gestalt approach with her particular interest—environmental education. Ms. Suttie has traveled extensively in Europe and the US and spent a year at St. Andrew's University, Scotland while an undergraduate. An avid backpacker, she has hiked the major mountain ranges of the Pacific northwest. Currently a resident of Santa Barbara, California, she finds the nearby San Rafael Wilderness and the coastal ranges ideal as settings for testing out her theories regarding the relationship between health and wilderness experience. Little is to be expected of that day... to which we are not awakened by our Genius, but by the mechanical nudgings of some servitor, are not awakened by our own newly acquired force and aspirations from within, accompanied by the undulations of celestial music, instead of factory bells...  相似文献   
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The desert tortoise (Gopherus agassizii) is federally listed as "threatened" and is afforded protection in several U.S. states including California, Nevada, Utah, and Arizona. Numerous factors ranging from habitat destruction to disease are thought to contribute to the species' decline throughout its range. Data collection on desert tortoises in the wild is challenging because tortoises are secretive, and many age and size classes are virtually undetectable in the wild. Detection dogs have been used for decades to assist humans, and the use of dogs for wildlife surveys is of increasing interest to scientists and wildlife managers. To address the basic question of whether dogs could be used to survey for the desert tortoise, we quantified the reliability and efficacy of dogs trained for this purpose. Efficacy is the number of tortoises that dogs find out of a known population. Reliability is a measure of how many times a dog performs its trained alert when it has found a tortoise. A series of experimental trials were designed to statistically quantify these metrics in the field setting where dogs trained to locate live desert tortoises were tested on their ability to find them on the surface, in burrows, and in mark-recapture surveys. Results indicated that dogs are effective at and can safely locate desert tortoises with reliability on the surface and are capable of detecting tortoises in burrows under a range of environmental conditions. Dogs found tortoises at the same statistical rate at temperatures between 12 degrees and 27 degrees C, relative humidity from 16% to 87%, and wind speeds up to 8 m/s. In both surface and burrow trials, dogs found >90% of the experimental animals. In comparative studies with humans, dogs found tortoises as small as 30 mm, whereas the smallest tortoise located by human survey teams was 110 mm. Although not all dogs or dog teams meet the requirements to conduct wildlife surveys, results from this study show the promise in using dogs to increase our knowledge of rare, threatened, and endangered species through improved data collection methods.  相似文献   
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Polyurethane foam (PUF) disks were deployed at global background sites, to test logistical issues associated with a global monitoring network for persistent organic pollutants (POPs). alpha-HCH, exhibited relatively high and uniform concentrations (17-150 pg/m3) at temperate and arctic sites with elevated concentrations associated with trans-Pacific inflow. Concentrations were much lower (<5 pg/m3) in Bermuda, Chile and Cape Grim. Concentrations for gamma-HCH, the main component of lindane, were spatially similar to the alpha-HCH pattern but lower in magnitude (typically, <10 pg/m3). Chlordane concentrations (sum of cis-chlordane, trans-chlordane and trans-nonachlor) were also low (<10 pg/m3). Dieldrin concentrations were in the range 2-25 pg/m3 at most sites but elevated in Bermuda. Back trajectories suggest that advection from Africa and the US may contribute. Endosulfan, a popular current-use pesticide, exhibited highest concentrations ranging from tens to hundreds of pg/m3. There was good agreement between duplicate samplers at each site and PUF disk-derived air concentrations agreed with high volume data. Few logistical/analytical problems were encountered in this pilot study.  相似文献   
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Maintenance of biodiversity through seed banks and botanical gardens, where the wealth of species’ genetic variation may be preserved ex situ, is a major goal of conservation. However, challenges can persist in optimizing ex situ collections if trade-offs exist among cost, effort, and conserving species evolutionary potential, particularly when genetic data are not available. We evaluated the genetic consequences of population preservation informed by geographic (isolation by distance [IBD]) and environmental (isolation by environment [IBE]) distance for ex situ collections for which population provenance is available. We used 19 genetic and genomic data sets from 15 plant species to assess the proportion of population genetic differentiation explained by geographic and environmental factors and to simulate ex situ collections prioritizing source populations based on pairwise geographic distance, environmental distance, or both. Specifically, we tested the impact prioritizing sampling based on these distances may have on the capture of neutral, functional, or putatively adaptive genetic diversity and differentiation. Individually, IBD and IBE explained limited population genetic differences across all 3 genetic marker classes (IBD, 10–16%; IBE, 1–5.5%). Together, they explained a substantial proportion of population genetic differences for functional (45%) and adaptive (71%) variation. Simulated ex situ collections revealed that inclusion of IBD, IBE, or both increased allelic diversity and genetic differentiation captured among populations, particularly for loci that may be important for adaptation. Thus, prioritizing population collections based on environmental and geographic distance data can optimize genetic variation captured ex situ. For the vast majority of plant species for which there is no genetic information, these data are invaluable to conservation because they can guide preservation of genetic variation needed to maintain evolutionary potential within collections.  相似文献   
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