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Dynamics of heavy metals such as Fe, Mn, Zn, Cr, Cu, Co, Ni, Pb, and Cd in surface water of Mahanadi River estuarine systems were studied taking 31 different stations and three different seasons. This study demonstrates that the elemental concentrations are extremely variable and most of them are higher than the World river average. Among the heavy metals, iron is present at highest concentration while cadmium is at the least. The spatial pattern of heavy metals suggests that their anthropogenic sources are possibly from two major fertilizer plants and municipal sewage from three major towns as well as agricultural runoff. The temporal variations for metals like Fe, Cu, and Pb exhibit higher values during the monsoon season, which are related to agricultural runoff. Concentrations of Ni, Pb, and Cd exceed the maximum permissible limits of surface water quality in some polluted stations and pose health risks. Dissolved heavy metals like Fe, Mn, Cr, Ni, and Pb exhibit a non-conservative behavior during estuarine mixing, while Zn, Cu, and Co distribution is conservative. Distribution of cadmium in the estuarine region indicates some mobilization which may be due to desorption. The enrichment ratio data suggest that various industrial wastes and municipal wastes contribute most of the dissolved metals in the Mahanadi River. The Mahanadi River transports 18.216 × 103 t of total heavy metals into the Bay of Bengal and the calculated rate of erosion in the basin is 128.645 kg km − 2 year − 1.  相似文献   
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Recent interest in the charismatic leadership role of managers in organizations calls for the identification and measurement of perceived behavior characteristics of such leadership. This article reports on the development of a questionnaire measure of the perceived behavioral dimensions of charismatic leadership proposed by the Conger and Kanungo (1987, 1988) model. Data were collected from 488 managers belonging to four organizations located in the U.S.A. and Canada. Analysis of the results revealed sound psychometric properties of the measure with adequate reliability, convergent and discriminant validity coefficients, and a stable factor structure. Implications of the measure for future research and practice are discussed.  相似文献   
3.
Sewage-sullage mixture from Raipur city is spread over a vast area surrounding the city. This mixture has a pH always above neutrality with high turbidity. Transparency was nil with the absence of phenolphthalein alkalinity and dissolved oxygen. Hardness was high with low nitrogen and phosphorus concentration. Human consumable. acquatic macrophytes are cultivated in such waste water. Net primary productivity of three macrophytes: Ipomoea aquatica, Marsilea quadrifolia and Nelumbo nucifera were evaluated while being cultivated in such sewage-sullage mixture. Productivity was determined either with periodic biomass removal (I. aquatica and M. quadrifolia) or through removing the biomass only once at the time of growing season (N. nucifera). Growing season productivity of up to 27.48. 19.81 and 9.49 g m(-2) and day(-1) and extrapolated productivity of up to 100.30, 72.31 and 34.64 mt. ha(-1) yr(-1) was recorded for I. aquatica. M. quadrifolia and N. nucifera respectively. Thus, these macrophytes are yielding a high amount of human consumable biomass from an area which neither be a useless wetland.  相似文献   
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On the basis of the current theories of charismatic leadership, several possible follower effects were identified. It is hypothesized that followers of charismatic leaders could be distinguished by their greater reverence, trust, and satisfaction with their leader and by a heightened sense of collective identity, perceived group task performance, and feelings of empowerment. Using the Conger–Kanungo charismatic leadership scale and measures of the hypothesized follower effects, an empirical study was conducted on a sample of 252 managers using structural equation modelling. The results show a strong relationship between follower reverence and charismatic leadership. Follower trust and satisfaction, however, are mediated through leader reverence. Followers' sense of collective identity and perceived group task performance are affected by charismatic leadership. Feelings of empowerment are mediated through the followers' sense of collective identity and perceived group task performance. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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