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Consumer demand for environmentally and socially responsible products is the driving force behind the expansion of competing certification systems. Paradoxically, this has led to an increasingly crowded marketplace for labels and confusion among stakeholders such as producers, retailers and buyers, rather than providing clear and reliable product information as intended. The situation has sparked a debate about the future of certification schemes and the need for a more streamlined system. This article explores some of the innovative ideas coming from the current discussion regarding biofuel certification and standardisation and outlines how those ideas can be applied to create a global generic standard-setting scheme for natural resources.  相似文献   
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Stephanie Matti 《Disasters》2015,39(4):626-647
Since 2001, there has been a growing consensus that sexual exploitation and abuse of intended beneficiaries by humanitarian workers is a real and widespread problem that requires governance. Codes of conduct have been promoted as a key mechanism for governing the sexual behaviour of humanitarian workers and, ultimately, preventing sexual exploitation and abuse (PSEA). This article presents a systematic study of PSEA codes of conduct adopted by humanitarian non‐governmental organisations (NGOs) and how they govern the sexual behaviour of humanitarian workers. It draws on Foucault's analytics of governance and speech act theory to examine the findings of a survey of references to codes of conduct made on the websites of 100 humanitarian NGOs, and to analyse some features of the organisation‐specific PSEA codes identified.  相似文献   
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The pH on the frustule of individual cells of the marine centric diatoms Coscinodiscus granii and Coscinodiscus wailesii (Bacillariophyceae) was measured with pH microsensors in culture media with increasing pH values of 8.04, 8.14, and 8.22, respectively. In 85–96% of the C. granii cells the pH on the frustule was up to 0.4 units higher than that of the medium, reaching a maximum pH 8.95. Only in 2–3% the surface pH exceeded that of the medium by up to 0.7 pH units. These results strongly suggest that diatoms in batch cultures differ, at least temporarily, in their individual photosynthetic activities. Infection experiments with the parasitoid nanoflagellate Pirsonia diadema (Stramenopile) showed that flagellates failed to infect when the culture pH was 8.8 and above. pH measurements on freshly infected C. granii showed that the prevalence of infection was higher in tendency on diatoms with low surface pH. Application of these results to parasitoid-diatom interactions in natural waters suggests that within phytoplankton populations a strong photosynthetic activity might prevent diatom cells temporarily from infection by pH-sensitive parasitoids.  相似文献   
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Kamel SJ  Mrosovsky N 《Ecology》2006,87(11):2947-2952
Within a single population of hawksbill sea turtles (Eretmochelys imbricata), we found a behavioral polymorphism for maternal nest site choice with respect to beach microhabitat characteristics. Some females preferred to nest in littoral forest and in places with overstory vegetation cover, and others preferred to nest in more open, deforested areas. Nest site choice was consistent within and between nesting seasons two years apart. This was not a result of females simply returning to the same location along the shoreline; beach sections used by individual turtles varied between seasons. Nest site choice was not influenced by changes in beach environment (e.g., beach width and foliage cover) or by changes in females' reproductive output (e.g., clutch size), suggesting that fidelity to particular microhabitats is a major determinant of the observed nesting patterns. Because hawksbills exhibit temperature-dependent sex determination, if the behavioral polymorphism in nest site choice has a genetic basis, as is plausible, then this would have implications for sex ratio evolution and offspring survival. By taking an individual-based approach to the study of maternal behavior we reveal previously overlooked individual variation and hope to provide some impetus for more detailed studies of nest site choice.  相似文献   
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Objectives: Nationally, animal–motor vehicle crashes (AVCs) account for 4.4% of all types of motor vehicle crashes (MVCs). AVCs are a safety risk for drivers and animals and many National Park Service (NPS) units (e.g., national park, national monument, or national parkway) have known AVC risk factors, including rural locations and substantial animal densities. We sought to describe conditions and circumstances involving AVCs to guide traffic and wildlife management for prevention of AVCs in select NPS units.

Methods: We conducted an analysis using NPS law enforcement MVC data. An MVC is a collision involving an in-transit motor vehicle that occurred or began on a public roadway. An AVC is characterized as a collision between a motor vehicle and an animal. A non-AVC is a crash between a motor vehicle and any object other than an animal or noncollision event (e.g., rollover crash). The final data for analysis included 54,068 records from 51 NPS units during 1990–2013. Counts and proportions were calculated for categorical variables and medians and ranges were calculated for continuous variables. We used Pearson’s chi-square to compare circumstances of AVCs and non-AVCs. Data were compiled at the park regional level; NPS parks are assigned to 1 of 7 regions based on the park’s location.

Results: AVCs accounted for 10.4% (5,643 of 54,068) of all MVCs from 51 NPS units. The Northeast (2,021 of 5,643; 35.8%) and Intermountain (1,180 of 5,643; 20.9%) regions had the largest percentage of the total AVC burden. November was the peak month for AVCs across all regions (881 of 5,643; 15.6%); however, seasonality varied by park geographic regions. The highest counts of AVCs were reported during fall for the National Capital, Northeast/Southeast, and Northeast regions; winter for the Southeast region; and summer for Intermountain and Pacific West regions.

Conclusions: AVCs represent a public health and wildlife safety concern for NPS units. AVCs in select NPS units were approximately 2-fold higher than the national percentage for AVCs. The peak season for AVCs varied by NPS region. Knowledge of region-specific seasonality patterns for AVCs can help NPS staff develop mitigation strategies for use primarily during peak AVC months. Improving AVC data collection might provide NPS with a more complete understanding of risk factors and seasonal trends for specific NPS units. By collecting information concerning the animal species hit, park managers can better understand the impacts of AVC to wildlife population health.  相似文献   

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