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101.
Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.  相似文献   
102.
Biotic pressure in and around protected areas (PA) is the primary cause of biodiversity loss in many developing countries across the globe. The pressure comes partly from biomass energy dependency in the form of heavy extraction of fuelwood from the forests. Although biomass fuels provide easily accessible and affordable sources of domestic energy to the rural masses, their combustion results in environmental and health‐related hazards. The objectives of this paper are to assess the patterns of household energy use in a subsistence forest economy and analyze the factors that influence their energy use choice for cooking and lighting. The paper uses primary data collected randomly from 244 households located in and around the Similipal Tiger Reserve (STR), situated in the eastern Indian state of Odisha. Age of the household head, number of days in wage employment, number of adult males and females in a household, education of the household head and landholding size are found to be the major variables that determine household fuelwood collection sources inside the reserve. Considering household structure as an income indicator, the analysis clearly shows that non‐poor households prefer to use clean energy (i.e. solar) for lighting, while poor households tend to use solid fuel. Energy policies for development should be based on the realistic proposition that fuelwood will remain the major source of energy for cooking for substantial proportions of the world’s population. Promotion of public education, social forestry schemes and fuel‐efficient improved chulhas should be encouraged in order to reduce household dependence on fuelwood. Moreover, devolving sufficient property rights over forest resources to local communities may help secure their broad‐based and active participation in the decision‐making process, which may result in a positive change in the attitude of the local people towards biodiversity conservation.  相似文献   
103.
Understanding what shape values (which ultimately shape human behavior) will help improve the effectiveness of conservation solutions that depend on public support. To contribute to this understanding, we investigated the influence of societal‐level changes, such as modernization, on values in a multilevel framework. We collected survey responses (n = 4183) to questionnaires mailed to a random selection of households within each county in Washington (U.S.A.) (response rate 32%). We used multilevel modeling to determine the relationship between modernization (e.g., county‐level urbanization, wealth, and education) and wildlife value orientations (values that shape thought about wildlife) while controlling for individual‐level sociodemographics. We then explored how values influence conservation support at different levels (e.g., individual and county) and how values explain conservation support in a case study of public responses to wolf (Canis lupis) recovery. We found positive associations between county‐level examples of modernization and mutualism (a wildlife value orientation that prioritizes the perceived needs of wildlife) independent of a respondent's sociodemographics, and negative associations between modernization and domination (a wildlife value orientation that prioritizes human needs). Our results suggest that context has an additive impact on one's values; certain locations exhibited domination values, whereas others exhibited a mix of value types. This finding is important because actions that restrict human interests to promote biodiversity were negatively associated with domination and positively associated with mutualism. In the wolf case study, mutualism was strongly correlated with less social conflict over wolf recovery in many, but not all, counties (e.g., Pearson's r correlation = 0.59 in one county and a nonsignificant correlation in another). Our findings suggest that modernization operates on values within a state with implications for biodiversity, but other factors in addition to values must be investigated to fully understand what leads to proconservation behavior.  相似文献   
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有机磷农药对乙酰胆碱酯酶的抑制作用及QSAR研究   总被引:2,自引:0,他引:2       下载免费PDF全文
以碘化硫代乙酰胆碱为底物,二硫代二硝基苯甲酸为显色剂,采用分光光度法测定了21种有机磷农药对乙酰胆碱酯酶(AChE)的半抑制浓度(IC50).运用多元线性回归分析以及参数间的自相关分析建立有机磷农药对AChE抑制作用的QSAR模型.模型分析表明,有机磷农药对AChE的抑制作用主要受特定方向上的原子极化率及原子的电拓扑状态的影响,是多因素综合作用的结果.模型可解释高达78%的数据变异和显著的预测能力(q2=0.653),表明有机磷农药对AChE的抑制作用可借助结构活性关系模型进行预测与评价.  相似文献   
106.
Field and laboratory investigations were performed to study the distribution and functional significance of antilysozyme activity (ALA) in algal cultures. According to the results obtained, ALA as a trait is widespread among green and blue-green algae but is expressed to different extents. Experiments on the algae–zooplankters model showed that ALA is a factor facilitating the survival of algae in freshwater communities by promoting the establishment of their trophic and symbiotic relationships with other aquatic organisms. Analyzing the intrapopulation structure of algal cultures associated with zooplankters, it was shown that changes in the ALA of algal clones have adaptive significance, providing for a greater stability of algal populations in biocenoses.  相似文献   
107.
公众参与环保行为影响因素的实证研究   总被引:7,自引:0,他引:7  
依据环境意识和社会背景对环保行为的交互作用机理,采用2006年横截面数据对陕西公众环保行为的现状和影响因素分别进行了实证检验.回归分析发现公众陈述的环保行为整体得分尚不及格,但较1998年的全国平均得分有大幅提高;环保重要性、环保知识、受教育程度对个人环保习惯和公共环保行为的影响呈显著正相关;性别差异在个人环保习惯中表现突出,在公共环保行为中并不显著;收入、年龄、环保意义变量的影响都不显著.从个人环保习惯路径分析模型发现环保重要性是最显著的中介变量.最后,文章建议政府应该通过提高公众的环保重要性意识,并进一步提高他们的受教育程度和环保知识水平,且以女性为突破口来带动更广泛意义上的公众参与环保行为  相似文献   
108.
109.
A random sample of 1 000 subjects (20–65 years old) from the national population of Sweden received a questionnaire; 70% (n = 695) replied, of whom 532 were occupationally active. Female gender, working with neck and/or body bent forward, arms above shoulders, and precision work tasks were predictors of musculoskeletal symptoms. Neck, shoulder, and upper back symptoms were more common in a strained situation at work (high demands, low control) (adjusted odds ratios [adjOR] 2.76, 2.80, and 2.26, respectively). Among females, neck and shoulder symptoms were more common in an iso-strain situation (high demands, low control and low social support) (adjOR 4.43 and 3.69, respectively), and low back symptoms were more common at low social support combined with a passive work situation (adjOR 3.35). No associations were found between iso-strain model and symptoms among males. In conclusion, iso-strain work situation was associated with neck symptoms among females, even when controlling for ergonomic factors.  相似文献   
110.
This study sought to determine if spatiotemporal skills, represented by success in high level sport, transfer to driving and, if so, whether such transfer is mediated by the gender of the driver. Using an emergency-braking test, we compared the driving ability of male and female athletes and non-athletes and showed that athletes achieved significantly longer and therefore superior durations for time-to-contact. The advantage of athletic participation thus did not appear in movement time but rather in the ability to produce desirable performance in context. We found that males and females did not differ significantly with respect to driving, however, involvement in sport apparently transfers to aspects of driving and so provides benefits beyond the intrinsic reward of the sports activities themselves.  相似文献   
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