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971.
Two experimental studies were conducted to examine whether the stress‐buffering effects of behavioral control on work task responses varied as a function of procedural information. Study 1 manipulated low and high levels of task demands, behavioral control, and procedural information for 128 introductory psychology students completing an in‐basket activity. ANOVA procedures revealed a significant three‐way interaction among these variables in the prediction of subjective task performance and task satisfaction. It was found that procedural information buffered the negative effects of task demands on ratings of performance and satisfaction only under conditions of low behavioral control. This pattern of results suggests that procedural information may have a compensatory effect when the work environment is characterized by a combination of high task demands and low behavioral control. Study 2 (N=256) utilized simple and complex versions of the in‐basket activity to examine the extent to which the interactive relationship among task demands, behavioral control, and procedural information varied as a function of task complexity. There was further support for the stress‐buffering role of procedural information on work task responses under conditions of low behavioral control. This effect was, however, only present when the in‐basket activity was characterized by high task complexity, suggesting that the interactive relationship among these variables may depend on the type of tasks performed at work. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
972.
Bhopal Gas Tragedy was the worst industrial accident in the world where several thousand persons lost their lives. It occurred at the Union Carbide plant located inside the city of Bhopal and close to the railway station, at midnight of December 2-3, 1984 due to the leakage of MIC gas which took the local sleeping and floating population unawares.

This paper describes the experience of a transit passenger who reached the Bhopal Railway Station by train at about the same time when the deadly gas leakage occurred.  相似文献   

973.
The current study used Mintzberg's (1983) conceptualization of political will and political skill to evaluate the predictors and consequences of political behavior at work. As elements of political will, we hypothesized that need for achievement and intrinsic motivation would predict the use of political behavior at work. Furthermore, we argued that political skill would moderate the relationship between political behavior and emotional labor. Data gathered from employees (N = 193) representing a wide array of organizations substantiated the proposed relationships. Specifically, need for achievement and intrinsic motivation were positively associated with political behavior. In turn, those opting to employ political behavior at work experienced a higher degree of emotional labor, but this relationship was found to operate differently at low and high levels of political skill. Specifically, emotional labor was a consequence of political behavior for those low in political skill, but emotional labor reactions from political behavior were neutralized for individuals high in political skill. Implications of these results, strengths and limitations, and directions for future research are discussed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
974.
The concept of time perspective balance has attracted increased attention from scholars in the past decade, reflected in published evidence suggesting positive outcomes ranging from enhanced mood to life satisfaction for those individuals possessing balance among their past, present, and future time perspectives, and assumedly able to shift their time perspective to match situational demands. In this paper, we consider the notion of time perspective balance in an organizational setting within which much consequential adaptation often occurs—the team environment—and explore different configurations of time perspective balance in teams facing dynamic task contexts. Drawing from work on situational awareness, we first consider the mechanism by which time perspective balance likely influences individual adaptation in dynamic task-focused situations. Next, we postulate what types of team configurations—ones with more balanced time perspective uniformity or ones with more time perspective variety—might be more appropriate in dynamic contexts given key team conditions. We illustrate our analysis with examples from healthcare team settings and offer ideas for future research.  相似文献   
975.
Russian Journal of Ecology - Technogenic pollution can accelerate microevolutionary processes in natural populations. We estimated the nuclear DNA content of 10 Bromus inermis Leyss. samples from...  相似文献   
976.
Allergic respiratory disease due to common allergens of organic origin is wwell known. Less familiar, but of increasing importance, are chemicals of organic and inorganic nature, met as dusts, vapours, and fumes. Their relevance is shown in occupational respiratory allergic disorders. Confirmation is given by “real life,” simulated, occupational-type provocation tests. Controlled exposure with minute amounts for brief periods, thus closely simulating allergic sensitivity, can precisely identify etiological causes in often complex exposures. The capacity of these widely different agents in different forms to elicit the different patterns of asthmatic reactions, is a pointed example of their potential role, as well as the role of chemical agents in general. The introduction into indoor environments of such materials demands consideration of their possible allergenic ffects and of the need to recognise the various forms of allergic respiratory reaction they may cause.  相似文献   
977.
A major diesel emissions research program has been initiated by the U.S. Environmental Protection Agency to assess the human health risk associated with increased use of diesel automobiles. This program is intended to establish the mutagenic and carcinogenic potency of complex organics associated with diesel particles as well as comparative particle-bound organics from other environmental emissions for which human epidemiological data are available. The mobile source samples selected for this study were collected from a heavy-duty diesel engine, a series of light-duty diesel passenger cars, and a gasoline catalyst automobile. The comparative source samples incorporated into the study were cigarette smoke condensate, coke oven emissions, roofing tar emissions, and benzo(a)pyrene. The samples were tested using three mutagenic assays and four carcinogenic assays as prescribed by a test matrix. This report describes the study design, particle generation, and sample collection and preparation. A brief summary of the bioassays is also included.  相似文献   
978.
The temporal pattern and dose-rate dependence of liver cancer in rats fed 2-fluorenylacetamide (2-FAA) was compared to analytical formulas derived from a specific model. The model was based on the idea that carcinogens have two distinct actions on cells: (1) transformation and (2) acceleration of progression. Transformed cells are by definition progressing toward cancer, but their rate of progression may depend on several factors, specifically, the amount of carcinogen. In the experiments the carcinogen was removed from the diet after various times and the rate of tumor progression was estimated from the time of tumor occurrence. The results were consistent with the idea that 2-FAA accelerated the progression of the cancers. The model provides a simple explanation of Druckrey's law in that the temporal occurrence of tumors induced by a carcinogen represents the acceleration of a naturally occurring disease progression.  相似文献   
979.
In order to study the deposition on vegetation of plutonium arising from the testing of nuclear weapons and discharges from nuclear facilities, sheep faeces were collected from the South-west and North of England. The plutonium content of faeces has been shown to be a reproducible and sensitive indicator of deposition on herbage and, with this technique, plutonium discharged from the Sellafield Works of British Nuclear Fuels LImited can be detected 60 km from the site. On moorland pastures the concentration of 239+240Pu in faeces, expressed as activity per gram of ash, is roughly equal numerically to the deposit of plutonium on 1 m2 of vegetation.Some of the plutonium ingested by a grazing sheep is absorbed and the highest concentrations are found in liver. The liver of a sheep grazing on pasture where the 239+240Pu concentration in faeces was about 2 pCi (74 mBq) g−1 of ash, was found to contain <1% of the Generalised Derived Limit for mutton and offal, and the meat <0·001%.  相似文献   
980.
The “filter model” has been developed to explain the biologic effects of radiation and chemicals. We have examined nearly 300 sets of dose response data, of which 50 are presented here. Responses (induced by radiation and chemicals) which have been examined include in vitro survival studies on animal and plant tissues, induction of cellular aberrations and time to tumor or death. Similar data from in vivo studies has also been examined. All of the data appear to fit the model R = a lnD + b(lnD)2 + c, where R is the response, a and b are parameters fitted by regression to a particular set of data, and c is the response at zero (or lowest) dose. By writing this model in exponential form, it can be seen that the response R results from multistage filtering (by net amounts a and b) of the initial dose, D. The threshold is obtained from this model as the point, D?T, at which the second derivative becomes zero. This is given by D?T = exp(1 ? a2b) when a and b are oppositelt signed.  相似文献   
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