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1.
Large, complex energy models present considerable challenges to develop and test. Uncertainty assessments of such models provide only partial guidance on the quality of the results. We have developed a model quality assistance checklist to aid in this purpose. The model checklist provides diagnostic output in the form of a set of pitfalls for the model application. The checklist is applied here to an energy model for the problem of assessing energy use and greenhouse gas emissions. Use of the checklist suggests that results on this issue are contingent on a number of assumptions that are highly value-laden. When these assumptions are held fixed, the model is deemed capable of producing moderately robust results of relevance to climate policy over the longer term. Checklist responses also indicate that a number of details critical to policy choices or outcomes on this issue are not captured in the model, and model results should therefore be supplemented with alternative analyses.  相似文献   
2.
The cognitive‐perceptual conceptualisation of the psychological contract has dominated research in this field. In this paper, it is argued that locating the psychological contract at the level of the individual‐organisational relationship can offer rich insights into psychological contract dynamics. Using qualitative interview data from a research study exploring how managers and part‐timers deal with the transition from full to part‐time police work in the UK, it is argued that a multi‐perspective conceptualisation of the sources of the psychological contract is critical for understanding processes that lead to non‐mutuality of understandings. Specifically, it is argued that the institutional and organisational context, embedded in the actions of third parties and in management practices, can undermine the extent to which the manager and the employee can reach agreement about mutual obligations. The theoretical and policy implications of this position are developed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
3.
This study investigates the potential for perchlorate biodegradation in the sediments of the Las Vegas Wash area in Henderson, Nevada. The continuous transport of perchlorate from a contaminated seepage to the Las Vegas Wash, Lake Mead, and the Colorado River has resulted in considerable deposition of perchlorate along the sediments of the Las Vegas Wash. The contaminated sediments act as a distributed source of perchlorate, making efforts to stop the flow of perchlorate to the Colorado River very challenging. In this study, perchlorate‐ reducing bacteria were enumerated and microcosm tests were performed to investigate the role of indigenous microorganisms and the limitations to natural perchlorate biodegradation in the contaminated sediments. The results of microcosm tests revealed that, despite the high number of perchloratereducing bacteria present, natural perchlorate in the area appears to be limited by (1) high salinity levels, the presence of nitrate, and the low perchlorate concentrations present in the sediments and (2) an insufficient carbon source. However, the potential for in situ bioremediation of the sediments along the Wash area is considered to be high due to the presence of significant numbers of perchlorate‐ reducing bacteria and to the ease in which an additional carbon source could be provided to sustain nitrate and perchlorate biodegradation. The economics of this process are expected to be very favorable; however, detailed cost estimates, pilot‐scale testing, and permit applications are required before this concept can be applied. © 2005 Wiley Periodicals, Inc.  相似文献   
4.
High volume air sampling in Bermuda, Sable Island (Nova Scotia) and along a cruise track from the Gulf of Mexico to northeast coast of the USA, was carried out to assess air concentrations, particle-gas partitioning and transport of polyfluorinated chemicals (PFCs) in this region. Samples were collected in the summer of 2007. Targeted compounds included the neutral PFCs: fluorotelomer alcohols (FTOHs), perfluoroalkyl sulfonamides (FOSAs) and perfluoroalkyl sulfonamido ethanols (FOSEs).Among the FTOHs, 8:2 FTOH was dominant in all samples. Sum of the concentration of FTOHs (gas+particle phase) were higher in Bermuda (mean, 34 pg m?3) compared to Sable Island (mean, 16 pg m?3). In cruise samples, sum of FTOHs were highly variable (mean, 81 pg m?3) reflecting contributions from land-based sources in the northeast USA with concentrations reaching as high as 156 pg m?3.Among the FOSAs and FOSEs, MeFOSE was dominant in all samples. In Bermuda, levels of MeFOSE were exceptionally high (mean, 62 pg m?3), exceeding the FTOHs. Sable Island samples also exhibited the dominance of MeFOSE but at a lower concentration (mean, 15 pg m?3). MeFOSE air concentrations (pg m?3) in cruise samples ranged from 1.6 to 73 and were not linked to land-based sources. In fact high concentrations of MeFOSE observed in Bermuda were associated with air masses that originated over the Atlantic Ocean.The partitioning to particles for 8:2 FTOH, 10:2 FTOH, MeFOSE and EtFOSE ranged from as high as 15 to 42% for cruise samples to 0.9 to 14% in Bermuda. This study provides key information for validating and developing partitioning and transport models for the PFCs.  相似文献   
5.
Photochemical oxidant injury to ponderosa pine (Pinus ponderosa Laws) is a severe problem in the southern California mountains. Three-year-old ponderosa pines fumigated in controlled environment chambers with ozone at 0.15, 0.30, or 0.45 ppm had apparent photosynthesis rates reduced by 10, 70, and 85%, respectively, after 30 days exposure. A fumigation with 0.30 ppm ozone for 33 days depressed the cold perchloric acid extracted polysaccharides of both current and one-year-old needles by 40%. The 80% ethanol soluble sugar concentration of current year, ozone-injured needles increased 16% and that of the one-year-old needles decreased slightly. Both carbohydrate fractions of control trees in carbon-filtered air increased moderately. Higher, endogenous concentrations of ascorbic acid in needles did not protect the tissue from ozone injury. Apparent photosynthesis rate was a sensitive index for ozone dosage response. Needle carbohydrate depletion probably induces premature abscission.  相似文献   
6.
The climate simulations from atmospheric general circulation models (GCMs) are often used to analyze the potential effects of climate change on environmental resources. It has been demonstrated that there are differences among the simulations from various GCMs, on spatial scales ranging from global to regional. This paper quantifies the differences in temperature and precipitation simulated by three major GCMs for four specific regions: an agricultural region (the North American winter wheat belt), a hydrologic region (the Great Basin), a demographic region (the high-density population corridor of the northeast United States), and a political region (the state of Texas). Both the current (control) climate and the climatic response to a doubling of atmospheric carbon dioxide (CO2) are consideredIn each region, even when the data are averaged on a seasonal basis, marked differences occurred in the areal average climate simulated by the different GCMs for both the control climate and the doubled-CO2 climate. Thus, climate impact studies based on the simulations of more than one GCM could easily yield a range of possible results  相似文献   
7.
8.
This paper evaluates the adoption of standards as proof of and an incentive for sound environmental practice in business and industry. The paper outlines the origins of environmental management and the development of the first environmental management standard BS 7750. The background to quality management is outlined to provide a context for these developments. The paper then goes on to examine the likely success of BS 7750 in actually improving the environmental performance of organizations in the light of experience in the field of quality. Finally, alternative approaches are looked at as ways of achieving environmental improvement.  相似文献   
9.
This paper examined the effects of work and family stressors and conflicts on Air Force women's mental health and functioning. We analyzed data from a 1993 survey of representative stratified samples of 525 Air Force women from the active duty reserve and guard forces. The analyses of the data are guided by the comprehensive model of work–family conflict that has been tested by Frone, Russell, and Cooper (1992) using a large representative community sample. Structural equation modeling analyses provided support for the work–family conflict model. The analyses also provided support for an extension of the model, which included the separate effects of marital and parental roles on mental health. The extended model demonstrated that job and parental stresses had direct effects on work–family conflicts and that job and marital distress and family–work conflict had an independent adverse effect on mental health. Whereas job and parental involvement had a beneficial effect on distress, they had an adverse effect on work–family conflicts. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
10.
The Mytilus species complex consists of three closely related mussel species: Mytilus trossulus, Mytilus edulis, and Mytilus galloprovincialis, which are found globally in temperate intertidal waters. Introduction of one or more of these species have occurred world-wide via shipping and aquaculture. Stable hybrid zones have developed in areas where these species have come into contact, making the invasion process complex. On the east coast of Vancouver Island (VI), British Columbia (BC), Canada, the native (M. trossulus) and introduced species (M. edulis and M. galloprovincialis), as well as their hybrid offspring, occur sympatrically. This study used a common environment experiment to quantify growth and survival differences among native, introduced, and introgressed mussels on VI. Mussels were collected from an area of known hybridization and reared in cages from May to August 2006. The cages were deployed at a local site as well as a remote site (approximately 150 km apart), and the mussels were genotyped at two species-specific loci. Growth and survival, as fitness measures, were monitored: native, introduced, and introgressed individuals were compared between and within sites to determine whether growth and survival were independent of site and genotype. Overall, mussels reared at Quadra Island performed better than locally-reared mussels at Ladysmith. Specifically, introgressed mussels reared at Quadra Island performed better than all genotypes reared at Ladysmith, as well as better than native mussels reared at Quadra Island. Differences in survival and growth among the native, introduced and introgressed mussels may serve to explain the complex hybridization patterns and dynamics characteristic of the VI introgression zone.  相似文献   
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