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Training programs and warning labels have been advocated as a means of convincing consumers to follow safety precautions when using all-terrain vehicles (ATVs), and are emphasized in the recent consent decree signed between the Consumer Product Safety Commission and ATV manufacturers. An alternative approach is to mandate safe behavior through regulations and law. This field study of ATV operator behavior conducted in six states in 1988 and 1989 provides initial insight into the effectiveness of these approaches. Logit analysis revealed that helmet use was significantly higher when required by law or when riders had 3 or more years of riding experience. Helmet use was significantly lower when riders rode frequently, when helmets were perceived as uncomfortable or not used on motorcycles, and when subjects had been moderately or seriously injured in ATV accidents. The presence of warning labels, reading of a manual, and participation in a training course were not significantly related to helmet use.  相似文献   
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The ability of mussels (Perna viridis) and semi-permeable membrane devices (SPMDs) to accumulate polycyclic aromatic hydrocarbons (PAHs) and petroleum hydrocarbons (PHCs) from five sites in Hong Kong's coastal waters was compared. Mussels consistently had higher levels of contaminants, but their utility was limited at one highly polluted site due to mortality. Mussels and SPMDs ranked sites differently in terms of individual contaminant levels. Although SPMDs overcome many of the disadvantages of using living organisms to measure contaminants in marine waters, they cannot be used as "mimics" due to different PAH and PHC accumulation patterns.  相似文献   
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There are few empirical tests of the acoustic mate-guarding hypothesis for the function of duetting in birds. This hypothesis states that when females are fertile, males initiate many songs or answer most of their mates solo songs to form duets and repel rival males seeking extra-pair copulations. We tested the hypothesis by comparing song initiation and answer rates of males and females in socially monogamous buff-breasted wrens (Throthorus leucotis) during pre-fertile and fertile periods. During pre-fertile periods, males often sang for short periods before being answered by their mates, yet first duets were formed earlier relative to dawn and more duets were given during the dawn chorus on pre-fertile than fertile mornings. Males initiated more songs during pre-fertile than fertile periods, whereas there was no difference between stages in female song initiation rates. The proportion of songs answered by individuals of both sexes did not differ between breeding stages. Other mate-guarding behaviours, such as frequent copulation and maintaining close proximity to mates when fertile, did not appear to be important in this species, as no copulations were observed and there was no difference in the time pairs spent in close proximity when females were fertile or not. Parentage analysis revealed that only 3% of 31 broods had young that were likely the result of extra-pair paternity. These findings do not support the acoustic mate-guarding hypothesis, and suggest that the low rate of extra-pair paternity in buff-breasted wrens was maintained without the use of acoustic or traditional paternity guards.Communicated by R. Gibson  相似文献   
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The Use of Corridors by Mammals in Fragmented Australian Eucalypt Forests   总被引:4,自引:0,他引:4  
We used a replicated sampling program to examine the use of roadside corridors as habitat by native mammals. Our procedure compared the abundance and diversity of mammals in remnant forest, pasture, and two types of roadside corridor. Fixed transects were established in these four habitat types at six replicate sites. Spotlight, live-trap, and daytime observation surveys were used as census techniques. Few mammals were detected in pasture, and spotlighting revealed a higher total density of mammals in corridors than in forests, indicating corridors provide important habitat. Nevertheless, the number of species using corridors distant to forest was less than that in the corridors close to forest and the forest patches. Different species did not utilize corridors in the same way. We also found intraspecific differences in habitat use by one species of small mammal (Antechinus stuartii), which may have implications for the value of corridors to this species. Specifically, there was a higher proportion of males, and individuals of both sexes had lower body weight in corridors than in forests. Our study demonstrates that corridors can provide useful habitat for mammalian assemblages, but may not provide a complete solution to the problem of landscape fragmentation.  相似文献   
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Two dominant perspectives of job crafting—the original theory from Wrzesniewski and Dutton ( 2001 ) and the job demands resources perspective from Tims, Bakker, and Derks ( 2012 )—remain separate in research. To synthesize these perspectives, we propose a three‐level hierarchical structure of job crafting, and we identify the aggregate/superordinate nature of each major job crafting construct. The first level of the structure is job crafting orientation, or approach versus avoidance crafting, which we argue is an essential yet often neglected distinction in the literature. We address the debate surrounding cognitive crafting and identify crafting form (behavioral versus cognitive crafting) as the next hierarchical level of constructs. Finally, we concur that job resources and job demands, or crafting content, capture different ways that individuals craft their jobs. Using this integrated hierarchical structure, we were able to review antecedents and outcomes from both perspectives. We show, for example, that approach crafting in its behavioral form is very similar to other proactive behaviors in the way it functions, suggesting a need for closer synthesis with the broader proactive literature, whereas avoidance crafting appears to be less proactive and often dysfunctional. On the basis of our review, we develop a road map for future research.  相似文献   
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The role of social context (e.g., leadership, team climate, and organizational support) in shaping employee proactive behavior has received considerable attention and has been investigated across multiple forms of proactive behavior. However, the research has not been well integrated. In this review, we adopt a multilevel approach to synthesize what is known about how social context factors influence employees' proactive behavior, as well as what mechanisms underpin these effects. Our analyses show that leader‐, team‐, and organization‐related social context factors mainly influence employee proactivity through shaping “reason to,” “can do,” and “energized to” states (i.e., proactive motivational states) via individual‐, team‐, and cross‐level processes. That has been most frequently investigated is the effect of the discretionary social context, particularly leadership, on proactive behavior. We also review the interaction effects between social context factors and other factors on employee proactive behavior and found inconsistent support for the motivational‐fit perspective that stimuli with the same directions enhance each other's effect. We offer a research agenda to advance theoretical insights on this important topic.  相似文献   
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Paul Foley 《环境政策》2017,26(5):915-937
To contribute to the literature on transnational sustainability governance hybrids, a new fisheries certification program in Iceland that was originally developed as an alternative to the non-governmental Marine Stewardship Council is examined. While this new program appears on the surface to constitute a purely nationalistic reaction against external non-state authority, the new governance institution is also non-governmental and incorporates international norms and institutions. To explain this new governance hybrid, Robert Cox’s International Political Economy approach to production and power is engaged. This approach theorizes the co-constitution of the social forces of production, state–society complexes and global governance. It is argued that the Icelandic case is not entirely localized or unique; it is part of a broader movement in which social forces of production respond to new market-oriented transnational sustainability governance institutions by developing territorially embedded but transnationally legitimate alternatives.  相似文献   
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