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221.
Previous research has shown that dispositional negative affect (NA) is associated with lower levels of job satisfaction. Little research has been conducted, however, on other organizational implications of negative affect or on the potential effects of dispositional positive affect (PA). The present studies examined the relationship of both positive and negative affectivity to organizational commitment, turnover intentions, global job satisfaction and performance. In the first study both NA and PA were associated with organizational commitment and turnover intentions. Additionally, commitment mediated the relationship between dispositional affectivity and turnover. Finally, PA and tenure interacted to predict job performance, such that PA and job performance were positively related, but only for high tenure employees. In Study 2 the findings were generally similar, but not identical. Both NA and PA were related to global job satisfaction and turnover intentions. However, only PA was related to affective organizational commitment. Moreover, both job satisfaction and affective commitment mediated the relationship between dispositional affectivity and turnover intentions. Finally, unlike Study 1, PA was not related to job performance. Rather, NA and tenure interacted such that when individuals were lower in tenure, NA was negatively related to performance. 相似文献
222.
This article presents an analysis of the prospective costs of RCRA corrective action for private, nonfederal facilities. Two data bases developed by Research Triangle Institute and a remedial action cost model developed by CH2M Hill provide the foundation for this work. The methodology has two components, a remedial action knowledge base and a discrete-state Monte Carlo analysis. Under base case assumptions, it is estimated that the total costs of RCRA corrective action will be $240 billion, with a 5 percent chance the costs will be less than $170 billion and a 5 percent chance the costs will be more than $377 billion. 相似文献
223.
Recent years have seen the environment emerge as one of the most pressing issues facing American business. Eventually, environmental costs will affect the bottom line of every American company. A recent study in the National Law Journal estimates that cleanup of the nation's known hazardous wastes sites will cost $752 billion over thirty years under current environmental policies. Environmental legislation and regulations impose annual compliance costs estimated by the Environmental Protection Agency at more than $30 billion. In the near future, environmental expenses for cleanup, regulatory compliance, and management are anticipated to grow to between 2.5 and 3 percent of GNP. Corporations that wish to be competitive must successfully manage these costs while maintaining or improving their role as responsible corporate citizens. Implementing a comprehensive system for identifying and managing environmental costs requires a multidisciplinary team effort. Environmental costs impact product selection, design and pricing, capital budgeting, and future strategic direction. In order to make informed and meaningful managerial decisions on environmental programs, real cost data are vital. An environmental management systems (EMS) requires information to set goals and then monitor progress towards those goals over time. This article will discuss the current cost accounting systems (CASs) available to support the myriad goals of environmental management systems. In addition, the article will outline a framework for plotting the location of your current EMS on a matrix of regulatory and information requirements and evaluating whether your corporation's CAS is adequate to support the goals and objectives set by your environmental management program. By anticipating future regulatory and information requirements, flexible systems can be developed to adapt to new and more stringent regulations and more complex information requirements. 相似文献
224.
Thomas R. Wentworth George P. Johnson Russell L. Kologiski 《Journal of the American Water Resources Association》1988,24(2):389-396
ABSTRACT: Weighted averages (WA) was investigated as a vegetation-based method for wetland designation, to be used in conjunction with the wetland indicator status of plants from Wetland Plants of the United States of America 1986 (Reed, 1986). Ecological indices were assigned to indicator groups and were used to compute weighted averages for quantitative data obtained from four studies of wetland vegetation conducted in various regions of the United States. Weighted averages of vegetation data proved to be a useful tool for assessing wetland status of the vegetation types included in our study: (1) rankings of vegetation stands or types by WA correlated well with their positions on environmental moisture gradients; and (2) the results of WA could be used, together with a wetland/upland break-point, to designate vegetation types as wetland or upland in a way that agreed well, in three of the four studies, with an alternative classification of wetland habitats. The variation of weighted averages among the sampling units representing a vegetation type was generally small relative to the range of ecological indices assigned. However, designations based on weighted average scores close to the break-point should be considered provisional and must be verified with supplementary data on soils and hydrology. 相似文献
225.
Russell Schoof 《Journal of the American Water Resources Association》1983,19(1):15-21
ABSTRACT: West Bitter Creek floodwater retarding structure site 3 in South Central Oklahoma was instrumented and records obtained and analyzed to obtain information concerning an impoundment water budget that is useful to landowners and designers of these impoundments. On-site loss of water from the impoundment was only 17 percent of the inflow during three years when the annual precipitation averaged 26 inches and the annual inflow averaged 1.4 inches. Runoff from an eroded area with no farm ponds was about 70 percent greater per unit area than from a portion of the watershed where 71 percent of the drainage area was controlled by farm ponds. A previous study indicated, however, that the ponds were reducing runoff only 13 percent. Loss of top soil increases runoff considerably. Only 24 percent of the total runoff into the impoundment was base flow. The flow rate into the impoundment was less than 0.05 cfs 70 percent of the time, and the inflow rate exceeded 10 cfs only 1 percent of the time. SCS runoff curve numbers varied between 57 and 96 for the impoundment watershed with an inverse relation between precipitation amount and curve number apprently caused by partial area runoff from impervious and semi-impervious areas. A comparison of measured event runoff versus event runoff computed by the SCS curve numbers gave an r2 of only 0.44. However, the total computed surface runoff for eight years of record was less than 1 percent below the measured runoff which indicated the curve number method was a good tool for predicting long term runoff for the watershed. 相似文献
226.
Water scarcity is increasing internationally and now is also affecting the natural water resources of New Zealand. This paper explores two solutions at a local level—water-storage and water-sharing regimes—that address the problems of water scarcity and competition for water, towards more sustainable development. Both systems show positive effects on the local economy and for the local community, providing additional jobs to the region and increasing the value added. Environmental benefits mostly relate to a lessening of the impacts of water abstraction by keeping flow volumes above minimum requirements. Locally operated water-storage and water-sharing schemes thus can provide excellent governance strategies for water management, ensuring that local interest and issues are addressed adequately. 相似文献
227.
Michael D. Lebowitz Mary Kaye O'Rourke Russell Dodge Catharine J. Holberg Gregory Corman Robert W. Hoshaw Jack L. Pinnas Robert A. Barbee Mark R. Sneller 《Environment international》1982,8(1-6)
Asthmatic and nonasthmatic families in a representative community population sample have been monitored over a 2-year period using daily diaries. Simultaneous micro-indoor and outdoor monitoring has been conducted in a representative sample of houses for air pollutants, pollen, fungi, algae, and climate. Macromonitoring of air pollutants and pollen was conducted simultaneously. The relationship of indoor to outdoor and micro to macro factors can be demonstrated. Acute symptoms were strongly related to age, weakly related to sex, and not related to smoking habits. The qualitative relationship of these micro and macro factors to symptoms in asthmatic and nonasthmatic families have been explored. Suspended particulate matter and pollen were related to symptoms in asthmatics and nonasthmatics. Fungi might be related to symptoms as well. The use of gas stoves is qualitatively related to symptoms. Algae and other contaminants of evaporative coolers do not appear to be important in producing symptoms. More complex statistical analyses are required to determine interactions of these factors. Distinction has to be drawn between infectious episodes, allergic episodes, nonallergic but similar episodes, and asthmatic attacks. This study demonstrates the need for further investigations in this area. 相似文献
228.
Very little is known of the factors controlling soil-to-plant transfer of radionuclides in tropical environments. As part of an IAEA/FAO coordinated research project (CRP) designed to elucidate some of those factors, near-surface samples of two agricultural red-earth soils (Blain and Tippera) were collected from a study site in the Northern Territory. The climate is tropical monsoonal with crops being grown over the wet season from December to March/April. It is important to understand soil variables that may be related to this dramatic seasonality. In this investigation, soil redox state and microbial populations were assessed before and after the growing season with a view to generating hypotheses for future evaluation. The X-ray absorption near edge structure (XANES) technique was used to determine overall changes in the solid-state redox speciation of Fe and Mn in soils across the growing period. Fe speciation did not change but approximately 10% of the total Mn was oxidised from Mn(II) to Mn(III) and Mn(IV) in both soils between October 1999 and April 2000. An apparent disconnect between Fe and Mn was not unexpected given the >10 times higher concentration of Fe in the soils compared with Mn. These results have implications for the bioavailability of redox sensitive radionuclides such as Tc and Pu. Similarly, microbial population estimates were derived before and after the growing period. Total bacterial populations did not vary from 10(6) to 10(7) colonies per gram. Fungal populations increased over the growing season from 3-6 x 10(5) to 1-4 x 10(6) colonies per gram of soil. Fungi have the potential to decrease soil pH and hence increase the bioavailability of radionuclides such as Cs. In addition, fungi act to facilitate plant nutrition. This could lead to enhanced accumulation of nutrient analogues (e.g. Sr and Ra for Ca; Tc for Mn), but this effect may be masked by improved biomass production. 相似文献
229.
Cerumen, or propolis, is a mixture of plant resins enriched with bee secretions. In Australia, stingless bees are important
pollinators that use cerumen for nest construction and possibly for colony’s health. While extensive research attests to the
therapeutic properties of honeybee (Apis mellifera) propolis, the biological and medicinal properties of Australian stingless bee cerumen are largely unknown. In this study,
the chemical and biological properties of polar extracts of cerumen from Tetragonula carbonaria in South East Queensland, Australia were investigated using gas chromatography-mass spectrometry (GC-MS) analyses and in
vitro 5-lipoxygenase (5-LOX) cell-free assays. Extracts were tested against comparative (commercial tincture of A. mellifera propolis) and positive controls (Trolox and gallic acid). Distinct GC-MS fingerprints of a mixed diterpenic profile typical
of native bee cerumen were obtained with pimaric acid (6.31 ± 0.97%, w/w), isopimaric acid (12.23 ± 3.03%, w/w), and gallic
acid (5.79 ± 0.81%, w/w) tentatively identified as useful chemical markers. Characteristic flavonoids and prenylated phenolics
found in honeybee propolis were absent. Cerumen extracts from T. carbonaria inhibited activity of 5-LOX, an enzyme known to catalyse production of proinflammatory mediators (IC50 19.97 ± 2.67 μg/ml, mean ± SEM, n = 4). Extracts had similar potency to Trolox (IC50 12.78 ± 1.82 μg/ml), but were less potent than honeybee propolis (IC50 5.90 ± 0.62 μg/ml) or gallic acid (IC50 5.62 ± 0.35 μg/ml, P < 0.001). These findings warrant further investigation of the ecological and medicinal properties of this stingless bee cerumen,
which may herald a commercial potential for the Australian beekeeping industry. 相似文献
230.
INTRODUCTION: Attention-Deficit/Hyperactivity Disorder (ADHD) may interfere with driving competence, predisposing those with the disorder to impaired driving performance and greater risk for adverse driving outcomes. Effective treatment may minimize the risk in those with ADHD. METHOD: We reviewed the scientific literature on driving risks and impairments associated with ADHD and the effects of stimulants on driving performance. Several lines of evidence were considered, including longitudinal studies and community-derived sample studies. The present review is based on a weekly review (by the first author) of all journals in the behavioral and social sciences indexed in the publication Current Contents spanning the past 15 years, as well as a search of the reference section of all studies found that pertained to driving risks associated with ADHD or to the treatment of ADHD as it relates to driving difficulties. RESULTS: The review of the scientific literature demonstrated well-documented driving risks and impairments associated with ADHD and the positive effects of stimulant medications on driving performance. CONCLUSIONS: Clinicians should educate patients/caregivers about the increased risk of adverse outcomes among untreated individuals with ADHD and the role of medication in potentially improving driving performance. IMPACT ON INDUSTRY: Owing to the significantly higher risk of adverse driving outcomes, the use of stimulant medications to treat people with ADHD who drive may reduce such safety risks. 相似文献