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41.
This research tested a multilevel model examining the influence of work‐family culture and supportive workplace relationships on work interference with family. Web‐based survey data were provided by 792 information technology employees from 10 organizations. Random coefficient modeling was used to test a path model examining the relationships between work‐family culture, leader‐member exchange (LMX), coworker support, and work interference with family. The direct effects of LMX and coworker support on work interference with family were significant. The indirect effect of work‐family culture on work interference with family was also significant. Results demonstrate the value of work‐family culture in understanding supportive supervisory and coworker relationships and work interference with family and highlight the need to employ multilevel models to understand these relationships. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
42.
During early development in fish, phospholipase A2 (EC 3.1.1.4) regulates membrane lipid modifications, which relates to changes in environmental conditions and provision of fatty acids required for metabolic energy substrates and prostaglandin biosynthesis. A method to analyze phospholipase A2 in rat tissues has been modified to measure its activity in embryonic Atlantic halibut (Hippoglossus hippoglossus L.). Egg and embryo samples were collected during the 1994 spawning season. Enzyme activity was undetectable at fertilization but in 10-d embryos was 230 pmol mg−1 h−1 (at 20 °C) and increased by ∼120% at hatch (17-d). Significant alterations in the fatty acid composition of important phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), were also observed. The content of some critical polyunsaturated fatty acids, and the ratio of unsaturated/saturated fatty acids, declined significantly over development. Acyl-chain restructuring mediated through the activity of phospholipase A2, coupled with other observed lipid changes (significant increases in the PC/PE ratio and cholesterol content), would produce a decreased fluidity of membranes during embryonic development, coinciding with the predicted upward movement of larvae in the water column. Arachidonic acid (20:4n-6) removed from PE could serve as a precursor for biosynthesis of 2-series prostaglandins, and eicosapentaenoic acid (20:5n-3) from PC is a likely source for other prostaglandin types. Despite removal of polyunsaturated fatty acids, there was an overall increase in lipid and fatty acid concentration, which can be attributed to amino acid catabolism during early developmental stages. Received: 9 September 1996 / Accepted: 8 September 1997  相似文献   
43.
An intrinsic biodegradation study involving the design and implementation of innovative environmental diagnostic tools was conducted to evaluate whether monitored natural attenuation (MNA) could be considered as part of the remedial strategy to treat an aerobic aquifer contaminated with 1,4-dioxane and trichloroethene (TCE). In this study, advanced molecular biological and stable isotopic tools were applied to confirm in situ intrinsic biodegradation of 1,4-dioxane and TCE. Analyses of Bio-Trap? samplers and groundwater samples collected from monitoring wells verified the abundance of bacteria and enzymes capable of aerobically degrading TCE and 1,4-dioxane. Furthermore, phospholipid fatty acid analysis with stable isotope probes (PLFA-SIP) of the microbial community validated the ability for microbial degradation of TCE and 1,4-dioxane. Compound specific isotope analysis (CSIA) of groundwater samples for TCE resulted in δ(13)C values that indicated likely biodegradation of TCE in three of the four monitoring wells sampled. Results of the MNA evaluation showed that enzymes capable of aerobically degrading TCE and 1,4-dioxane were present, abundant, and active in the aquifer. Taken together, these results provide direct evidence of the occurrence of TCE and 1,4-dioxane biodegradation at the study site, supporting the selection of MNA as part of the final remedy at some point in the future.  相似文献   
44.
Caribbean pine, an economically important tree of tropical lowlands, is at risk of SO2 exposure in certain locales. Twenty-week old seedlings of Caribbean, Scots, and Virginia pine were exposed to 0.5, 1.0, and 2.0 ppm SO2 (1300, 2600, and 5200 μm?3, respectively) for 1, 2, 4, and 8 h in modified controlled-environment chambers. Severity of SO2-induced leaf necrosis for each species was related to SO2 concentration and exposure duration using a regression model. The three dose-response relationships differed in detail, but Caribbean pine seedlings were generally as sensitive to SO2 as seedlings of the two highly sensitive temperate species. In addition, 173 4-wk-old Caribbean pine seedlings were exposed to 0.5 ppm SO2 for 4 h. Over one-half of these seedlings exhibited some necrosis and over one-sixth had more than 5 percent of leaf surface necrotic. It is concluded that Caribbean pine seedlings are highly sensitive to acute doses of SO2.  相似文献   
45.
The cost effectiveness of catchment-wide funding for the environmental remediation of urban waterways on the scale of a major metropolitan catchment is examined considering the typical land-use and pollutant-export characteristics of urban catchments. The evaluation is performed by comparing the effectiveness of the major stormwater treatment modes for the pollutants of concern with the proportion of pollutant export to which the measure applies. The heavy metals copper, lead, and zinc in the aqueous phase or bound to fine particulates are identified as representative of the pollutants of concern in drainage from urban catchments. The analysis suggests that these priority pollutants are predominantly (79–87%) derived from runoff from residential property and roads as disseminated urban surfaces. Analysis of a specific case of catchment-wide funding of stormwater remediation in the Sydney Harbour catchment, Australia reveals that the funding allocation cannot be expected to have achieved reductions in the loads of priority pollutants due to the types of treatment measures implemented and the sources addressed. The apportionment of funding in better accordance with the maximum potential effectiveness of stormwater treatment modes and the pollutant-export characteristics of urban catchments could thus be expected to achieve a more cost-effective result from such funding initiatives.  相似文献   
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48.
Environmental planning legislation in New South Wales now requires local government authorities to draw up statutory plans that take into account, among other concerns, both the biophysical and the social environmental issues within their jurisdictions. The SIRO-PLAN method of plan production provides a systematic mechanism for fulfilling this requirement. This article describes the application of the method by planning researchers over 18 months to the production of a Local Environmental Plan for a rural local government in New South Wales. The policy formulation, the purposive data collection, and the deliberate adjustment of plans in order to recognize interest group requirements were all found to be valuable features of the method, while the translation of the ultimately chosen land-use plan into the explicit regulatory controls available to the local government authority was found to require further refinement. The capacity of SIRO-PLAN to quantify the resolution of competing environmental concerns in the final plan, although of value to planning researchers, proved too arcane for traditionally trained planners.  相似文献   
49.
Summary The author presents a personal view of the role and functions of both the Australian Heritage Commission and the Australian Register of the National Estate. Operational problems are highlighted, and a critique of the Commission and difficulties encountered in working within both national and federal political confines, are outlined. In a decade, the Commission has achieved much towards the preservation of the Australian environment: important in the Commission's current activity is the task of explaining to the lay public precisely what heritage conservation entails and why it is an essential activity.Professor Bruce Davis has been, in the past, Chairman of the Australian Heritage Commission and the contents of this paper are based upon his delivery of an address at the inaugural conference of the Environment Institute of Australia, in Sydney, during November 1987. The views expressed are the personal opinion of the author and should not be construed as necessarily representing the policy of views of any institution with which the author may be connected.  相似文献   
50.
The objective of this research was to analyze the retention of acid precipitation as a viable policy issue on the Congressional agenda during the 1980s. Issue maintenance (a term borrowed from Barbara Nelson's discussion of the four stages associated with agenda decision making) was examined in relation to a set of issue characteristics originally developed by Roger Cobb and Charles Elder, i.e., concreteness, social significance, temporal relevance, complexity, and categorical precedence. Each issue attribute was found to be somewhat useful in explaining the longevity of acid rain as an agenda item although the direction of influence for two factors, complexity and temporal relevance, was contrary to expectations. It was suggested that a conceptual merger of this sort could contribute to the comparative analysis of agenda policy decisions by providing a clearer and more restricted set of decision points to be explained.  相似文献   
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