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821.
822.
Canada's Action Plan is the federal response to its international obligation under the UN Framework Convention of 1992 whereby Canada must reduce its greenhouse gas emissions to the 1990 level by the year 2000. The Plan is failing completely, because of its essentially voluntary nature. Overall, greenhouse gas emissions will have increased 13 per cent in Canada between 1990 and 2000, four per cent more than the population increase for that period. Five other plans studied by government agencies are projected to fail to achieve the called-for reductions in emission. An analogous plan, the Rational Energy Plan, developed by a network of nongovernment organizations, is projected to enable the federal government to achieve its obligations under the Framework Convention and also its further obligations under the 1995 Berlin Mandate. This Plan has been analyzed using the government's own analytical tools which project that it will offer Canada substantial annual increases in employment for at least ten years, more prosperous households for more than ten years, and a smaller federal deficit for at least eight years. The federal government has no viable alternative to adopting this plan as soon as practicable. This paper explains some of the needed preliminaries to introducing the Plan, together with examples of tax-shifting and of easily implemented stick-and-carrot inducements to making the Plan work in a sea of partly hostile provinces (Alberta, Saskatchewan, Ontario and Newfoundland). The Plan will not be easy to implement because of necessary changes in human habits of thinking and attitudes. A new and simple strategy for reducing fuel wastage on highways is introduced in this paper; and also the concept of extended cogeneration, the Rational Energy Plan itself being a particularly fine example.  相似文献   
823.
Emerging infectious diseases are characterized by complex interactions among disease agents, vectors, wildlife, humans, and the environment. Since the appearance of West Nile virus (WNV) in New York City in 1999, it has infected over 8,000 people in the United States, resulting in several hundred deaths in 46 contiguous states. The virus is transmitted by mosquitoes and maintained in various bird reservoir hosts. Its unexpected introduction, high morbidity, and rapid spread have left public health agencies facing severe time constraints in a theory-poor environment, dependent largely on observational data collected by independent survey efforts and much uncertainty. Current knowledge may be expressed as a priori constraints on models learned from data. Accordingly, we applied a Bayesian probabilistic relational approach to generate spatially and temporally linked models from heterogeneous data sources. Using data collected from multiple independent sources in Maryland, we discovered the integrated context in which infected birds are plausible indicators for positive mosquito pools and human cases for 2001 and 2002.  相似文献   
824.
SHORT REVIEWS     
Books reviewed in this article: Paul Demeny and Geoffrey Mcnicoll (eds.), Encyclopedia of Population Barbara Ehrenreich and Arlie Russell Hochschild (eds.), Global Woman: Nannies, Maids, and Sex Workers in the New Economy Food and Agriculture Organization of the United Nations, World Agriculture: Towards 2015/2030: An FAO Perspective and Summary Report Jeanne X. Kasperson and Roger E. Kasperson, Global Environmental Risk Richard Lynn, Eugenics: A Reassessment Douglas W. Maynard, Hanneke Houtkoop‐Steenstra, Nora Gate Schaeffer, and Johannes van der Zouwen (eds.), Standardization and Tacit Knowledge: Interaction and Practice in the Survey Anthony M. Messina (ed.), West European Immigration and Immigrant Policy in the New Century  相似文献   
825.
826.
The operations of the dispatch department of a manufacturing organization have been analysed in terms of matching the labour supply to the labour demand (as determined by customer orders). The problem differed somewhat from those traditionally associated with dispatch departments since set-up costs and company policy resulted in high stocks being carried. In this context, service level did not refer to the ability to supply a customer from stock, but to the proportion of orders processed within a specified time interval. The operations of the department were simulated using FINSIM—a computer simulation package developed for the BBC microcomputer. FINSIM offers the capability of seeing the simulation proceed graphically on a visual display. The final outcome of the study was an aid to decision-making consisting of a family of curves of service level against the maximum acceptable time allowed to process an order. This set of curves allowed prediction of the quantifiable consequences of any proposed changes in the department. Of particular significance was the use of the curves to help demonstrate that the seemingly important delays to order documentation within the computer department were in fact inconsequential.  相似文献   
827.
This paper advances knowledge regarding how fathers and mothers perceive and experience flexible working opportunities. It does this through applying the theoretical concept ‘belonging’ to ‘Parsonian’ classifications of parenting and work. In so doing it makes transparent the misconceptions and inequities which exist among parents and their organizational environments. Focusing initially on a qualitative study of fathers’ experience of working flexibly, the paper shows how fathers felt marginalized from the possibilities of flexible work due to line managers’ assumptions that men belonged to an ‘instrumental’ economic provider group. The paper contributes a new angle to debate by articulating how fathers perceived employed mothers as belonging to an ‘expressive’ child‐oriented group, with privileged access to flexibility. However, drawing upon a study of maternity and flexible work we query fathers’ assumptions that flexibility was easily available to mothers, suggesting that fathers’ perceptions of maternal privilege were misconceived. While mothers were categorized as belonging within an ‘expressive’ group associated with childcare, they were nevertheless discouraged from accessing flexibility. Inequities between women and men (with regard to flexibility) thus appeared to be less significant than fathers supposed.  相似文献   
828.
Balkan endemic nephropathy (BEN) is a chronic, progressive wasting disease of the kidneys, endemic in certain rural regions of the Balkan nations Croatia, Serbia, Bulgaria, and Romania. It is irreversible and ultimately fatal. Though this disease was first described in the 1950s, its causes have been a mystery and a source of much academic and clinical contention. Possible etiologic agents that have been explored include exposure to metals and metalloids, viruses and bacteria, and the dietary toxins aristolochic acid (AA) and ochratoxin A (OTA). AA is a toxin produced by weeds of the genus Aristolochia, common in Balkan wheat fields. Aristolochia seeds may intermingle with harvested grains and thus inadvertently enter human diets. OTA is a mycotoxin (fungal toxin) common in many foods, including cereal grains. In this study, we analyzed the weight of evidence for each of the suspected causes of BEN using the Bradford Hill criteria (BHC): nine conditions that determine weight of evidence for a causal relationship between an agent and a disease. Each agent postulated to cause BEN was evaluated using the nine criteria, and for each criterion was given a rating based on the strength of the association between exposure to the substance and BEN. From the overall available scientific evidence for each of these suspected risk factors, AA is the agent with the greatest weight of evidence in causing BEN. We describe other methods for testing causality from epidemiological studies, which support this conclusion of AA causing BEN.  相似文献   
829.
Microbiological food safety is an important economic and health issue in the context of globalization and presents food business operators with new challenges in providing safe foods. The hazard analysis and critical control point approach involve identifying the main steps in food processing and the physical and chemical parameters that have an impact on the safety of foods. In the risk‐based approach, as defined in the Codex Alimentarius, controlling these parameters in such a way that the final products meet a food safety objective (FSO), fixed by the competent authorities, is a big challenge and of great interest to the food business operators. Process risk models, issued from the quantitative microbiological risk assessment framework, provide useful tools in this respect. We propose a methodology, called multivariate factor mapping (MFM), for establishing a link between process parameters and compliance with a FSO. For a stochastic and dynamic process risk model of in soft cheese made from pasteurized milk with many uncertain inputs, multivariate sensitivity analysis and MFM are combined to (i) identify the critical control points (CCPs) for throughout the food chain and (ii) compute the critical limits of the most influential process parameters, located at the CCPs, with regard to the specific process implemented in the model. Due to certain forms of interaction among parameters, the results show some new possibilities for the management of microbiological hazards when a FSO is specified.  相似文献   
830.
When policymakers and private agents use models, the economists who design the model have an incentive to alter it in order to influence outcomes in a fashion consistent with their own preferences. I discuss some consequences of the existence of such ideological bias. In particular, I analyze the role of measurement infrastructures such as national statistical institutes, the extent to which intellectual competition between different schools of thought may lead to polarization of views over some parameters and at the same time to consensus over other parameters, and finally how the attempt to preserve influence can lead to degenerative research programs.  相似文献   
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