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151.
This study investigates the complexities involved in the relationships between perceptions of politics and work outcomes by examining the effects of political behavior on that relationship. More specifically, we suggest that political behavior may serve as a form of control or as a mechanism for coping with highly political organizational environments perceived by individuals to be aversive. As such, we propose moderating roles of self‐promotion and ingratiation on the relationships between perceptions of politics and the work outcomes of satisfaction with job in general, satisfaction with supervision, and intent to leave. It was hypothesized that increased exercise of self‐promotion and ingratiation behaviors would mitigate the negative effects of perceptions of organizational politics on those specific outcomes. Hypotheses were supported for the proposed relationships between self‐promotion and two of the work outcomes: satisfaction with supervision and intent to leave. Significant effects were also found for ingratiation; however, they were opposite to those proposed for the perceptions of organizational politics–intent to leave relationship. Implications of results and areas for future research are discussed. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
152.
The selection of new settlement areas and the construction of safe buildings, as well as rendering built‐up areas safe, are of great importance in mitigating the damage caused by natural disasters. Most cities in Turkey are unprepared for natural hazards. In this paper, Çanakkale, located in a first‐degree seismic zone and sprawled around the Sartçay Delta, is examined in terms of its physical vulnerability to natural hazards. Residential areas are analysed using GIS (geographic information system) and remote‐sensing technologies in relation to selected indicators. Residential areas of the city are divided into zones according to an evaluation of geological characteristics, the built‐up area's features, and urban infrastructure, and four risk zones are determined. The results of the analysis show that the areas of the city suitable for housing are very limited. In addition, the historical centre and the housing areas near Sartçay stream are shown to be most problematic in terms of natural disasters and sustainability.  相似文献   
153.
People frequently have to work in high repetitive jobs. Previous research has focused exclusively on the effects of task repetitiveness on well‐being, while neglecting effects on work performance. In the present study, we aimed to fill this void by conducting two workplace simulations with experimental manipulations of task repetitiveness. Participants worked for about 5 hours at either a computer workstation, compiling computer hardware packages according to customer requests (Experiment 1, N = 160), or at an assembly line, piecing together equipment sets for furniture (Experiment 2, N = 213). Both experiments provide consistent evidence that high repetitiveness has a detrimental effect on well‐being, whereas work performance increases under conditions of high repetitiveness. On a practical level, our study hence shows that high task repetitiveness is a double‐edged sword for both employees and organizations. On a conceptual level, our findings emphasize the necessity to account for both mental strain and work performance when examining the effects of task repetitiveness. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
154.
Drawing on self‐determination and self‐concept‐based theories, this study investigated the mediating effects of psychological empowerment and organization‐based self‐esteem on the relationship between supervisory mentoring and employee performance and the moderating effect of supervisor political skill on the direct and first stage of the indirect effects. Data were obtained from a sample of 330 subordinate–supervisor dyads from the People's Republic of China. Using PROCESS of conditional indirect effect, we found support for the moderated direct and indirect effects of supervisory mentoring. First, supervisor political skill moderates the direct effect of supervisory mentoring on employee promotability. Second, supervisor political skill moderates the indirect effect of supervisory mentoring on the following: (i) employee promotability via both psychological empowerment and organization‐based self‐esteem and (ii) contextual performance only via psychological empowerment. These direct and indirect effects of supervisory mentoring are stronger when supervisors demonstrate a higher level of political skill. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
155.
This study describes a multilevel examination of person–group (PG) fit perceptions in a sample of 1023 individuals working in 92 teams at a private sector R&D firm. Using confirmatory factor analysis and multilevel random coefficient modeling, we provide evidence that perceptions of team‐level collective fit are unique from aggregated individual‐level PG fit perceptions at the individual and team levels. We demonstrate that collective values‐based and abilities‐based fit perceptions showed unique and positive relationships with team cohesion, team efficacy, and team performance, after accounting for aggregated individual perceptions of PG fit. Results also demonstrate that cohesion partially mediates the relationship between collective fit and team performance. Cross‐level effects were also supported, indicating that collective fit explains additional variance in individual‐level outcomes, beyond individual‐level PG fit perceptions. The usefulness of employing a multilevel approach to studying PG fit is discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
156.
Voltammetry provides new insights into the effects exerted in vitro by methylation of native DNA. Applying single sweep voltammetry at a stationary mercury electrode the successive steps of the destabilization of alkylated DNA are investigated. The methylation of the nucleic acids is manifested by a specific electrochemical response, due to the 7‐methylguanine, a major product of the methylation of DNA. Short time effects of the methylation include the labilization of 4 to 5 base pairs per methylated guanine base. Furthermore, uncommon protonation properties of the base 7‐methylguanine‐cytosine have been detected. Long term effects of the methylation are ultimately spontaneous hydrolytic strand breaks induced by the prior depurination connected with the release of the 7‐methylguanine from the methylated DNA. A half time t1/2 of 102 h for the depurination at 37°C has been determined. The depurination and the subsequent strand breaks alter the hydrodynamic properties of the damaged DNA, an effect which can be sensitively followed with voltammetry via the resulting changes in the diffusion coefficient of the damaged biopolymer.  相似文献   
157.
Die Kenntnis biochemischer Veränderungen von lipophilen körperfremden Stoffen ist hinsichtlich deren Elimination aus dem Organismus, sowie bei Überlegungen zur Voraussage toxischer, insbesondere carcinogener Wirkungen von vorrangiger Bedeutung  相似文献   
158.
This study concerns the polycyclic aromatic hydrocarbons (PAH's) emission from gasoline and diesel automobile engines.

The sampling procedure, the extraction and the analytical method are presented. Using the gas chromatography‐mass spectrometry technique it is possible to detect and quantify easily about 15 PAH's. Data obtained on exhaust particles collected from gasoline and diesel automobile engines are presented and discussed.  相似文献   
159.
Although several polydimethylsiloxane oligomers are taken up by fish after dietary and aqueous exposure, they do not significantly accumulate, despite their high hydrophobicity compared to polychlorinated biphenyls. For both cyclic and linear oligomers with less than fourteen silicon units, this is probably due to short half life times. For all oligomers these were less than 4.5 days. Linear oligomers with more than fourteen silicon units were not detectable in fish, probably due to a lack of uptake.

After dietary exposure the body burden of PDMS oligomers usually never exceeded the daily exposure dose. The biomagnification factors were less than 0.06, whereas for 2, 2’, 5, 5'‐tetrachlorobiphenyl 1.4 was found.

After aqueous exposure, bioconcentration factors were all less than 1200 for PDMS oligomers, and 27,000 for the biphenyl. In addition it was found that the uptake rate constants of the silicon compounds from water by fish were comparable to those of other hydrophobic chemicals such as PCB's. Hence it was concluded that the relatively low bioconcentration and biomagnification factors of PDMS oligomers with less than fourteen silicon units must be explained by rapid elimination, rather than by slow uptake.  相似文献   
160.
A sensitive, accurate and reproducible method for the analysis of metoclopramide, a gastrointestinal drug, has been described. An isocratic HPLC elution method was employed which requires about 10 minutes to be performed. The concentration of metoclopramide hydrochloride preparations was found to be 95.1 ±0.3% and 94.21 ±0.25% in tablet and injection formulations, respectively.  相似文献   
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