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41.
This paper focuses on policy change under scientific uncertainty. This is done by exploring two case studies of Canadian pesticide policy evolution applied to Sabatier's ‘Advocacy Coalition Framework’. ‘Stakeholder’ and ‘narrative policy’ analyses are emphasised to understand pesticide policy changes in Calgary (public education without a restrictive by-law) and Halifax (restrictive by-law). The parallel case studies consist of qualitative interviews with members of pesticide policy advisory committees in each city and a content analysis of local newspaper articles. Key resources mobilised by coalitions to achieve their policy goals include skillful leadership, and the use by those leaders of the media to disseminate coalition narratives. Further, the context of policy change contributed to the scenarios whereby pro-by-law grassroots activists were particularly successful in Halifax and anti-by-law city employees were most influential in Calgary.  相似文献   
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Nest protection through egg relocation from natural nests into protected hatcheries is a common practice used at rookeries around the world to increase hatchling recruitment into sea turtle populations. However, rarely have the impacts of this practice on hatchling recruitment and quality been assessed. This study investigated the influences of the thermal nest environment of olive ridley turtles Lepidochelys olivacea on emergence success and quality of hatchlings of hatchery nests in Alas Purwo National Park, East Java, Indonesia (2009 and 2010 nesting seasons). Nest temperatures above 34?°C for at least 3 consecutive days during incubation in the hatchery resulted in decreases in emergence success and locomotor performance of hatchlings. The use of the hatchery is recommended due to extremely high predation rate of nests left on the beach; however, altering hatchery management practice by spacing nests one meter apart and providing shade should improve hatchery outcomes now and into the future.  相似文献   
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Incidents in Great Britain reported to the Health and Safety Executive during 1996/97 and 1997/98 involving fires, explosions, runaway chemical reactions and unignited releases of flammable materials are reviewed. Statistical comparisons are made against previous years based on the materials involved, and a number of common themes and causes are identified.  相似文献   
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Phosphorus-based land application limits for manure have increased the importance of optimizing diet P management and accurately characterizing the bioavailability of manure P. We examined the effects of pig (Sus scrofa) diets formulated with high-available-P corn and phytase on P levels in excreta and slurry stored for 30, 60, 90, 120, and 150 d. Twenty-four pigs (approximately 14 kg each) were fed one of four low-P diets: (i) normal corn, no phytase (control); (ii) normal corn with 600 phytase units kg(-1) (PHY); (iii) high-available-P corn, no phytase (HAP); and (iv) high-available-P corn with 600 phytase units kg(-1) (HAP + PHY). Fresh fecal and stored slurry dry matter (DM) was analyzed for total phosphorus (TP), dissolved molybdate-reactive phosphorus (DRP), dissolved organic phosphorus (DOP), acid-soluble reactive phosphorus (ASRP), acid-soluble organic phosphorus (ASOP), and phytate phosphorus (PAP). The PHY, HAP, and HAP + PHY diets significantly (alpha = 0.05) decreased fecal TP 19, 17, and 40%, respectively, compared with the control. Dissolved reactive P was 36% lower in the HAP + PHY diet compared with the other diets. Relative fractions (percent of TP) of DRP, DOP, ASOP, and PAP in slurry generally decreased with storage time up to 150 d, with the largest decreases occurring within 60 to 90 d. Diet-induced differences in relative fractions of DRP, DOP, ASRP, and PAP were significant when averaged across storage times, simulating a mixed-age slurry. Relative fractions of DRP in simulated mixed-age slurries were higher in HAP and HAP + PHY diets, indicating that diet may affect P losses under certain P-based application scenarios.  相似文献   
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The temporal and spatial variability in infestation rate of the chiton Lepidochitona cinereus (L.) by the sporozoan Minchinia chitonis (Lankester, 1885) is described and discussed for twelve sites in Scotland and Northern Ireland sampled in 1987. Sites where the population of L. cinereus were heavily infected displayed greater modal lengths than those with only a small proportion of infected individuals. Temporal observations at Easthaven and Watersound revealed different changes in population structure and infestation rates. The Watersound population showed both reduced size range and infestation rate compared with Easthaven, where the infection rate increased between 1978 and 1987. The degree of infection of an individual L. cinereus is divided into three categories; light, medium and heavy. These categories have been defined by both gross and microscopic histological observations.Please address all correspondence to Dr. Baxter at his second address in Northern Ireland  相似文献   
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Growth and population structure of Lepidochitona cinereus was studied at Easthaven in Scotland. Length was isometrically related to height and breadth, while tissue dry weight was negatively allometric. Length-shell weight relationships were variable with the time of year. Periods of differential growth were associated with the onset of growth in spring and gonad development in July. The use of growth-check lines to age individuals is described. Population structure and growth was investigated using a combination of winter growth-check line and length-frequency analyses. Infection with the protozoan Minchinia chitonis is shown to cause enhanced growth and deviation from the normal growth curve. Individuals survived for a maximum of 5 winters and length-frequency data could be interpreted only after growth-check line analysis due to extensive overlap of year-class size ranges. Year-class success was variable, and the present population was dominated by older year-classes.  相似文献   
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