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971.
ABSTRACTWe assess the impact of corporate social responsibility (CSR) of multinational oil companies (MOCs) on HIV/AIDS prevalence in Nigeria’s oil-producing communities. One thousand, two hundred households were sampled across the rural communities of Niger Delta. Using logit model, the main result indicates that General Memorandum of Understandings (GMoUs) have not significantly impacted on factors behind the spread of HIV/AIDs in rural communities. This implies that the impact of the disease on MOCs business, employees and their families, contractors, business partners and the oil communities have not inclined downward. The findings suggest that CSR offers an opportunity for MOCs to help address HIV/AID prevalence through a business case for stakeholders’ health in the region. It calls for MOCs to improve GMoUs health intervention on sensitisation campaigns, funding testing and counselling centres, subsidising anti-retroviral drugs, prevention of mother-to-child transmission, rehabilitation of orphaned and vulnerable children and other cares for people living with AIDS. 相似文献
972.
Joseph A. Veech 《Conservation biology》2000,14(1):140-147
Abstract: I tested the reliability of species-area curves for use in identifying hotspots, political or geographical regions of high species richness. On a species-area plot, hotspots are points (regions) that appear above the curve to a greater extent than other points. Because several different curves can be fit to species-area data, identification of hotspots may differ depending on the curve-fitting function used. I tested this hypothesis by comparing hotspots identified by the power function, the extreme value function, a linear function, and the exponential function. I examined several species-area data sets varying in size and in the presence of endemics. I defined hotspots as the highest 25% for small data sets and highest 10% and 25% for large data sets of standardized residuals from each function fitted to each data set. For some data sets, the functions agreed in identification of hotspots in that they identified 75% or more of the same hotspots. The extreme value function tended to identify hotspots not identified by the other three functions. For most data sets, the functions did not agree completely in identifying hotspots. Therefore, species-area curves should not be used as the sole means of identifying hotspots of species richness, although they can be used to examine the effect hotspot area has on richness for hotspots identified by other methods. 相似文献
973.
Because polyandry often confers substantial direct and indirect benefits, females might be advantaged if they limit their reproductive investment in a single male when additional partners are available. We tested whether females of the externally fertilizing zebrafish Danio rerio would withhold more of their clutch when immediate further matings were likely. We tested females in three treatments: overnight visual and olfactory exposure to either a single male, two males, or three males. Females were then allowed to mate with one of the males; in the two-male and three-male treatments, the additional males remained in visual and olfactory contact to simulate a high likelihood of additional mating. Available clutch was measured by leaving females to spawn with two novel males for an additional 60?min. In contrast to our expectations, females did not release a greater proportion of their clutch when only a single male was present. Instead, females in the single male treatment released significantly fewer eggs per spawning event and significantly fewer eggs over the full 70?min of the trial. The hypothesis that females adjust current reproductive investment support in relation to the likely availability of mating partners is not supported. Instead, females appear to lay fewer eggs when only one male is available, most likely as a result of physiological stimulation of oocyte maturation, or in response to the likely fertilization capacity of a single individual. 相似文献
974.
975.
In today’s context of waste management, landfilling of Municipal Solid Waste (MSW) is considered to be one of the standard practices worldwide. Leachate generated from municipal landfills has become a great threat to the surroundings as it contains high concentration of organics, ammonia and other toxic pollutants. Emphasis has to be placed on the removal of ammonia nitrogen in particular, derived from the nitrogen content of the MSW and it is a long term pollution problem in landfills which determines when the landfill can be considered stable. Several biological processes are available for the removal of ammonia but novel processes such as the Single Reactor System for High Activity Ammonia Removal over Nitrite (SHARON) and Anaerobic Ammonium Oxidation (ANAMMOX) process have great potential and several advantages over conventional processes. The combined SHARON–ANAMMOX process for municipal landfill leachate treatment is a new, innovative and significant approach that requires more research to identify and solve critical issues. This review addresses the operational parameters, microbiology, biochemistry and application of both the processes to remove ammonia from leachate. 相似文献
976.
Although most researchers now espouse a person‐by‐situation interactionist approach, there remains much work to be carried out to fully understand how different features of the environment interact with personality to influence behavior. Thus, this study sought to examine the moderating effects of three group‐level constructs on the relationships between two personality traits (conscientiousness and extraversion) and individual performance and counterproductive behaviors. Specifically, using trait activation theory as an organizing framework, we considered the moderating effects of the following: (i) a previously unexamined construct called core group evaluations (CGEs); (ii) group conscientiousness composition; and (iii) group extraversion composition. Data were obtained from a sample of university football players (N = 225–252 from 40 groups). The results indicated that CGEs moderated the relationships between individual conscientiousness and both performance (subjective) and counterproductive behaviors. Group conscientiousness composition also moderated the relationships between individual conscientiousness and both performance (objective and subjective) and counterproductive behaviors. Lastly, group extraversion composition moderated the relationship between individual extraversion and counterproductive behaviors. These findings highlight the importance of considering a team's CGEs, as well as the personality composition of team members when investigating the effects of conscientiousness and extraversion on individual performance and counterproductive behaviors. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
977.
This paper investigates the challenges and opportunities of how firms and organizations can and will be able to strike a better balance between economic growth and environmental stewardship in the context of China’s emerging ‘circular economy’ policy paradigm and based on ecological modernization theoretic approaches.Based on three company case studies in the information technology and electronic industries in China, we identify and demonstrate how a blended business and environmental value can be created from adopting a sustainable supply chain management approach. The adoption of a sustainable supply chain management approach is rapidly becoming a key business challenge and opportunity in China and other large emerging economies around the world, where our greatest environmental management challenges currently reside and will continue to exist for many years to come. The value creation framework proposed in research focuses on evaluating three case study companies who appear in various stages of an electronic industry supply chain. Value creation within a supply chain can provide the impetus for organizations to adopt circular economy, sustainable supply chain practices, for competitive reasons.In addition, we describe how a value proposition can be evaluated at two levels of analysis, a more specific micro-level and a more general meso-level of analysis. The four major business value dimensions include cost reduction, revenue generation, resiliency, and legitimacy and image.The initial findings are that a variety of opportunities exist for electronic firms in emerging and developing countries, while results from this study provide an important scholarly foundation to develop and refine sustainable supply chain management practices in emerging and developing economies. 相似文献
978.
Regional Environmental Change - Small Island Developing States (SIDS) are widely recognised as being very vulnerable to the impacts of climate change. In some manner, climate change will impact on... 相似文献
979.
J Thad Scott Robert D Doyle Shane J Prochnow Joseph D White 《Ecological applications》2008,18(3):805-819
N2 fixation can be an important source of N to limnetic ecosystems and can influence the structure of phytoplankton communities. However, watershed-scale conditions that favor N2 fixation in lakes and reservoirs have not been well studied. We measured N2 fixation and lacustrine variables monthly over a 19-month period in Waco Reservoir, Texas, USA, and linked these data with nutrient-loading estimates from a physically based watershed model. Readily available topographic, soil, land cover, effluent discharge, and climate data were used in the Soil and Water Assessment Tool (SWAT) to derive watershed nutrient-loading estimates. Categorical and regression tree (CART) analysis revealed that lacustrine and watershed correlates of N2 fixation were hierarchically structured. Lacustrine conditions showed greater predictive capability temporally. For instance, low NO3(-) concentration (<25 microg N/L) and high water temperatures (>27 degrees C) in the reservoir were correlated with the initiation of N2 fixation seasonally. When lacustrine conditions were favorable for N2 fixation, watershed conditions appeared to influence spatial patterns of N2 fixation within the reservoir. For example, spatially explicit patterns of N2 fixation were correlated with the ratio of N:P in nutrient loadings and the N loading rate, which were driven by anthropogenic activity in the watershed and periods of low stream flow, respectively. Although N2 fixation contributed <5% of the annual N load to the reservoir, 37% of the N load was derived from atmospheric N2 fixation during summertime when stream flow in the watershed was low. This study provides evidence that watershed anthropogenic activity can exert control on planktonic N2 fixation, but that temporality is controlled by lacustrine conditions. Furthermore, this study also supports suggestions that reduced inflows may increase the propensity of N2-fixing cyanobacterial blooms in receiving waters of anthropogenically modified landscapes. 相似文献
980.
Adam B. Munson Joseph J. Delfino Douglas A. Leeper 《Journal of the American Water Resources Association》2005,41(1):1-10
ABSTRACT: Florida water resources are among the most abundant in the United States, with Florida receiving the second‐highest mean annual rainfall of all states. However, water supply issues have troubled the state due to the highly variable spatial and temporal distributions of water supply and demand, and they are aggravated by the population's preference for settling in coastal regions where freshwater resources are scarce. Historically, the competing issues of water resource development and natural systems protection have placed water management agencies and local governments at odds. In 1997, the Florida Legislature enacted several major changes to Florida water law in an attempt to improve water resource planning and protection. This paper briefly reviews the history of water management in Florida with an emphasis on decisions culminating in the 1997 legislation, which requires the development of minimum flows and levels. Also examined is the impact of the 1997 law on water management. Efforts made to comply with legislative mandates are summarized; these include, to date, establishment of minimum flows and levels on 209 water bodies and budgeting in excess of $1.4 billion for water resource development projects. 相似文献