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211.
The application of anaerobically processed animal manure to maintain adequate levels of organic matter in arid soils is becoming a common practice. The purpose of this study was to characterize two farm manure products as compared with municipal waste compost (MWC). The anaerobic processing to obtain a biogas manure (BM) product was much faster (25 d) than the aerobic composting of farmyard manure (FYM) (90 d). Drying by three different methods (solar-drying, vacuum-drying at 45 degrees C, and freeze-drying) did not affect the quality of BM. Based on the chemical characteristics, FYM and BM products were comparable, and, containing less ash (30%) and heavy metals (50 mg Pb kg(-1)), seemed superior to MWC that contained 65% ash and 108 mg Pb kg(-1). On the other hand, MWC had higher C content (69.9%), lower acidity (15.04 mol kg(-1)), and higher exothermic peaks (300-460 degrees C) than BM and FYM (50% C, 20 mol kg(-1), and 275-450 degrees C, respectively), thus showing a greater extent of humification. Also, when the organic materials were incubated with arid soils and monitored for mean residence times (MRT), MWC was slightly more resistant to decomposition (MRT 175-180 d) than BM or FYM (MRT 161-166 d). The observed differences, however, were too small to dismiss any of the products as a valuable material for land applications to improve soil quality. In view of the results obtained, MWC may be considered an adequate substitute for BM or FYM, whenever the latter are in short supply.  相似文献   
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213.
This study applied the theoretical framework based on expectancy and discrepancy theories to examine how the elements of total compensation might influence work motivation and job satisfaction. The principal dimensions of total compensation that give rise to distinct reactions among employees were examined. Two samples of employees, 269 exempt employees and 297 nonexempt employees, were studied separately in order to identify the differences of reaction between these two groups. The relationships between the elements of total compensation, work motivation and job satisfaction were analysed by a structural equations model with LISREL VII. Proposals were developed to predict the conditions of compensation efficiency on work motivation and job satisfaction in the cultural context of employment in France. The three principal conclusions of the study were: (1) under certain conditions, individualized compensation of exempt employees can be a factor of work motivation; (2) flexible pay of nonexempt employees neither motivates nor increases job satisfaction; (3) benefits of exempt and nonexempt employees neither motivate nor increase job satisfaction. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
214.
Prior organizational shift work research has focused on studying either nurses or blue collar manufacturing employees, and been somewhat limited by shift size limitations. Using a unique sample of 705 full‐time medical technologists (MTs), across distinct fixed day, evening, night and rotating shifts, this study found that day shift MTs had lower job content routinization (more task enrichment) than evening, night and rotating shift MTs. Contrary to previous research, rotating shift MTs did not have lower work attitudes than fixed shift MTs. Results are further discussed. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
215.
Humble leadership is attracting increased scholarly attention, but little is known about its effects when used in conjunction with less humble leadership behaviors that rely on a perception of the leader as confident and charismatic. This study contrasts the effects on top management team (TMT) potency and organizational performance of a more humble (feedback seeking) and a less humble (vision) CEO leader behavior. We hypothesize that CEO feedback seeking increases TMT potency and firm performance by communicating to TMT members that the organization values their input and encouraging their own feedback seeking, whereas CEO vision articulation influences these outcomes by fostering greater clarity about the firm's direction, and an enhanced ability to coordinate efforts within the TMT. CEOs who have not developed a vision can achieve a similar positive impact on TMT potency and firm performance by seeking feedback. In a sample of CEOs and TMT members from 65 firms, both CEO feedback seeking and vision articulation exhibit positive direct relationships with firm performance. However, only feedback seeking displays an indirect effect on performance via TMT potency. Finally, CEO feedback seeking has its strongest effects on firm performance and TMT potency for CEOs who are not seen as having a vision.  相似文献   
216.
Environmental Science and Pollution Research - Wastewater treatment plant effluents from urban area are a well-known source of chronic multiple micropollution to the downstream living organisms. In...  相似文献   
217.
自20世纪中叶以来,五大湖区的水生食物网就已受到多氯联苯化合物(PCBs)的污染。对于长寿命鱼类,如湖鲟(Acipenser fulvescens),由于缺乏该物种的相对敏感性信息,一直无法确定其PCB暴露的风险。本文的研究目标就是评估湖鲟早期生命阶段对3,3''4,4''5-五氯联苯(PCB-126)或2,3,7,8-四氯二苯并-p-二恶英(TCDD)暴露的敏感性。死亡率、生长、形态和组织病理学、游泳能力和活动水平都被用作评估终点。心包和卵黄囊水肿、管状心脏、卵黄囊出血和体长较小是TCDD和PCB-126暴露中最常见的病理症状,早在受精4 d后就开始出现,其中许多的病理都以一种剂量依赖的方式发生。湖鲟体内PCB-126和TCDD的半致死剂量分别为5.4 ng/g egg(95%置信区间,3.9-7.4 ng/g egg)和0.61 ng/g egg (0.47-0.82 ng/g egg)。由此产生的PCB-126的相对强度因子(0.11)远大于世界卫生组织对鱼的估计值(毒性当量因子=0.005),这表明目前的风险评估可能低估了PCB对湖鲟的毒性。在受精60 d后,从半致死剂量中幸存的湖鲟的游泳活性和耐力均有所下降。阈值和半数效应毒性值表明,与在北美发现的另一种鲟鱼属Scaphirhynchu相比,湖鲟对PCB和TCDD更为敏感。事实上,在大湖区和其他地方的湖鲟种群都容易受到PCB/ TCDD诱导,使胚胎发育受到影响,游泳能力下降。
精选自Tillitt, D. E., Buckler, J. A., Nicks, D. K., Candrl, J. S., Claunch, R. A., Gale, R. W., Puglis, H. J., Little, E. E., Linbo, T. L. and Baker, M. (2017), Sensitivity of lake sturgeon (Acipenser fulvescens) early life stages to 2,3,7,8-tetrachlorodibenzo-P-dioxin and 3,3′,4,4′,5-pentachlorobiphenyl. Environmental Toxicology and Chemistry, 36: 988–998. doi: 10.1002/etc.3614
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3614/full
  相似文献   
218.
Multiple criteria evaluation (MCE) is often used with GIS to identify suitable sites for multi-purpose development such as ecotourism. Typically, expert or stakeholder consultation is used to identify weights reflecting the relative importance of map layers representing different criteria. The objective of this study was to evaluate a new consultative approach to GIS-based MCE, using ecotourism development in Kurdistan, Iraq, as a case study. In an initial and follow-up consultation, stakeholders were asked not only to assess the relative importance of different map layers for ecotourism development, but also to identify specific sites suitable for ecotourism. Seventy-eight ecotourism destinations nominated by participants had significantly higher MCE scores than a set of 58 locations chosen without reference to stakeholders (t-test = 21.16; p < 0.001). The approach thus provides a straightforward means of assessing the consistency of stakeholder input into MCE and could be adapted for use in other site suitability assessments.  相似文献   
219.
Environmental Science and Pollution Research - Risks of heavy metal exposure from contaminated indoor dust constitute a major threat to human health. In this paper, heavy metals in deposited indoor...  相似文献   
220.
Although job seekers' reputation perceptions may be based on different factors than other constituents (e.g., investors, consumers), we know little about the antecedents of job seekers' reputation perceptions. The present study utilizes verbal protocol analysis to explore the factors that job seekers consider when evaluating employers' reputations. Results from this qualitative investigation are complemented and cross‐validated with an experimental policy capturing study and a field study of recruiting organizations. Data from all three methodologies suggest that some factors affecting job seekers' reputation perceptions are quite different from factors that have been revealed in previous reputation research, which has focused primarily on executives. For example, results from the present study reveal that the type of industry in which a firm operates, the opportunities that a firm provides for employee development, and organizational culture affect job seekers' reputation perceptions. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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