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211.
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
212.
Raj Singhvi Ajay Taneja Jay Patel Charles Gasser Dennis J. Kalnicky 《Environmental Forensics》2014,15(1):17-24
The United States Environmental Protection Agency/Environmental Response Team (US EPA/ERT), in collaboration with St. John's College, Dr. B. R. Ambedkar University, Agra, India, is conducting a study to determine Hg vapor emission rates resulting from broken compact fluorescent lamps (CFLs) in a residential setting. The overall objectives of the study are to determine Hg vapor emission data and provide homeowners with cleanup procedures and disposal options for broken CFLs. Most of the currently available CFLs in the US market are manufactured in China for US companies. Several different types of CFLs were purchased from local stores and their Hg content was determined. Based on previous studies, such as the 2011 study by Singhvi and colleagues, five popular spiral CFLs were selected for emission studies in an acrylic chamber. This study found that Hg vapor emissions from CFLs may be significantly greater than those from beads of liquid Hg with weights comparable to the Hg content of the CFLs. The average 24-hour Hg loss into the atmosphere from CFLs broken on a plastic surface ranged from 0.6% to 22% of the bulb content, while that for CFLs broken on carpet ranged from 2.6% to 28%. Projections for a 12 foot × 9.33 foot × 8 foot (25.4 m3) room based on the chamber measurements in this study indicate that CFL breakage in some household settings may produce 24-hour Hg concentrations above the 2000 Agency for Toxic Substances and Disease Registry (ATSDR) minimum risk level (MRL) of 0.2 μg/m3, for typical air exchange rates. This study also indicates that Hg emission may not be proportional to exposed surface area based on experiments using liquid Hg with different surface areas. 相似文献
213.
Hong Wang Jay Gao Ruiliang Pu Liliang Ren Yan Kong He Li Ling Li 《Environmental monitoring and assessment》2014,186(7):4013-4028
This study aims to assess the relative importance of natural and anthropogenic variables on the change of the red-crowned crane habitat in the Yellow River Nature Reserve, East China using multitempopral remote sensing and geographic information system. Satellite images were used to detect the change in potential crane habitat, from which suitable crane habitat was determined by excluding fragmented habitat. In this study, a principal component analysis (PCA) with seven variables (channel flow, rainfall, temperature, sediment discharge, number of oil wells, total length of roads, and area of settlements) and linear regression analyses of potential and suitable habitat against the retained principal components were applied to explore the influences of natural and anthropogenic factors on the change of the red-crowned crane habitat. The experimental results indicate that suitable habitat decreased by 5,935 ha despite an increase of 1,409 ha in potential habitat from 1992 to 2008. The area of crane habitat changed caused by natural drivers such as progressive succession, retrogressive succession, and physical fragmentation is almost the same as that caused by anthropogenic forces such as land use change and behavioral fragmentation. The PCA and regression analyses revealed that natural factors (e.g., channel flow, rainfall, temperature, and sediment discharge) play an important role in the crane potential habitat change and human disturbances (e.g., oil wells, roads, and settlements) jointly explain 51.8 % of the variations in suitable habitat area, higher than 48.2 % contributed by natural factors. Thus, it is vital to reduce anthropogenic influences within the reserve in order to reverse the decline in the suitable crane habitat. 相似文献
214.
This study investigated the effects of individuals' affective traits (i.e., affect intensity and affect disposition) and affective states (i.e., positive and negative mood) on their motivations and behavior during episodes of organizational conflict. Two hundred and twenty‐three student employees from a variety of jobs and organizations kept daily records, for a three day period, of their conflict experiences at work. The results of hierarchical linear modelling indicated that employees' affective traits and affective states had parallel effects on the conflict management process. Subsequent analyses revealed the source of this parallelism: employees' moods on the day of the conflict fully mediated the effects of their affective disposition on the conflict process variables. The results are discussed in terms of their theoretical significance and practical implications. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
215.
Mechanical blending of contaminated soil with amendments has recently reemerged as an important treatment technology. From its original application using large‐diameter augers in the early 1990s to the current use of rotary drum blenders, soil blending is being used as an alternative to other remediation technologies like amendment injection and soil vapor and groundwater extraction. Shallow (approximately 10 m below ground surface [bgs] or less) soil blending also offers an alternative to excavation and disposal. Soil blending has been used to remediate a site with various contaminants including, but not limited to, chlorinated solvents, petroleum, and metals. The types of soils susceptible to soil blending vary from sands and gravels to silts and clays to fractured rock and combinations of all of these. The types of amendments blended include oxidants, reducing agents, biological enhancements, and stabilizing amendments. Soil blending systems deliver the power to the mixing head to adequately mix the soil and amendment to enhance remediation effectiveness. Since long‐term contamination is often a result of heterogeneously distributed residual contaminant in localized source zones that are difficult to access, the typical aim of soil blending is to homogenize the soil while effectively distributing amendment to these zones made accessible by blending. By effectively homogenizing the soil, however, soil blending will increase the void ratio and disrupt the shear strength and bearing capacity of the soil so an important component of a soil blending technology is proper recovery of these geotechnical parameters. This can be achieved by using well‐known soil improvement techniques such as amending all or a portion of the blended area with Portland cement or lime. Several case studies of soil blending treatments of different contaminants and amendments in various soil types are provided. 相似文献
216.
Optimal hardwood tree planting and forest reclamation policy on reclaimed surface mine lands in the Appalachian coal region 总被引:4,自引:0,他引:4
We study the optimal hardwood tree planting decision on reclaimed surface coal mines in the Appalachian region using a mine operator-focused, expected cost model that recognizes costs of preparing the site for tree planting, unit costs of planting seedlings, and opportunity costs of reforestation treatments and the performance bond. We also consider the possibility of failed initial attempts by incorporating the probability of reforestation success, based on empirical seedling ,survival rates and regulated tree survival standards, as well as fixed and unit costs of returning for additional planting. Optimal planting levels from 319 to 780 trees per acre and expected costs from $1049 to $2338 were found using simulations over a range of unit planting costs, fixed costs of replanting, tree survival standards, and interest rates. Further simulations compared optimal planting across un-weathered gray sandstone and weathered brown sandstone substrate materials, finding gray sandstone to be associated with lower expected costs. We conclude that optimal planting density and expected reforestation cost are sensitive to economic parameters, regulations, and planting substrate materials; and those policies influencing these factors may have substantial impact on reforestation outcomes and the choice of post-mining land use by mine operators. Our study provides a framework for understanding forest reclamation decisions that incorporates incentives faced by the mine operators who develop and implement the plans for mine reclamation, including forestry. 相似文献
217.
Jay?K.?Goldberg Alisa?K.?Wallace Stacey?L.?WeissEmail author 《Die Naturwissenschaften》2017,104(9-10):81
Sex pheromones can perform a variety of functions ranging from revealing the location of suitable mates to being honest signals of mate quality, and they are used in the mate selection process by many species of reptile. In this study, we determined whether the skin lipids of female striped plateau lizards (Sceloporus virgatus) can predict the reproductive quality of females, thereby having the potential to serve as pheromones. Using gas chromatography/mass spectrometry, we identified 17 compounds present in skin lipids of female lizards. Using principal component analysis to compare the skin lipid profile of receptive and non-receptive females, we determined that an uncharacterized compound may allow for chemical identification of receptive mates. We also compared extracted principal components to measures of female fitness and reproductive qualities and found that the level of two 18 carbon fatty acids present in a female’s skin lipids may indicate her clutch size. Finally, we compared the information content of the skin lipids to that of female-specific color ornaments to assess whether chemical and visual cues transmit different information or not. We found that the chroma of a female’s orange throat patch is also related to her clutch size, suggesting that chemical signals may reinforce the information communicated by visual ornamentation in this species which would support the “backup signals” hypothesis for multiple signals. 相似文献
218.
Maki BE Sibley KM Jaglal SB Bayley M Brooks D Fernie GR Flint AJ Gage W Liu BA McIlroy WE Mihailidis A Perry SD Popovic MR Pratt J Zettel JL 《Journal of Safety Research》2011,42(6):473-485
Problem
Falling is a leading cause of serious injury, loss of independence, and nursing-home admission in older adults. Impaired balance control is a major contributing factor.Methods
Results from our balance-control studies have been applied in the development of new and improved interventions and assessment tools. Initiatives to facilitate knowledge-translation of this work include setting up a new network of balance clinics, a research-user network and a research-user advisory board.Results
Our findings support the efficacy of the developed balance-training methods, balance-enhancing footwear, neuro-prosthesis, walker design, handrail-cueing system, and handrail-design recommendations in improving specific aspects of balance control.Impact on Knowledge Users
A new balance-assessment tool has been implemented in the first new balance clinic, a new balance-enhancing insole is available through pharmacies and other commercial outlets, and handrail design recommendations have been incorporated into 10 Canadian and American building codes. Work in progress is expected to have further impact. 相似文献219.
Doucet JJ Hill L Stout P Bansal V Lee J Fortlage D Potenza B Workman P Coimbra R 《Journal of Safety Research》2011,42(2):131-135
Objective
Pedicabs are a new and controversial transportation innovation for tourists in congested areas in several U.S. cities. Scant literature on this trauma mechanism exists. The purpose of this study is to identify the incidence, demographics, morbidity, mortality, and potential for injury prevention of pedicab incidents amongst major trauma admissions at an urban, academic Level I Trauma Center.Patients & Methods
Researchers conducted a retrospective review of the Trauma Registry from 2000 to 2009. All patients identified as being injured in a pedicab incident were reviewed. Demographics, diagnoses, toxicology, treatments, and injury severity scale (ISS) were collected. Outcomes included mortality, ICU, and hospital length of stay (LOS), discharge disposition, and hospital charges. A photographic survey of 50 local pedicabs was examined for the presence and use of safety equipment.Results
During the period of January 2000 to July 2009 there were 15 major trauma victims from identified pedicab incidents. Falling from the pedicab was the mechanism of injury in 14 of 15 cases. There were two fatalities in victims following severe traumatic brain injury. Traumatic brain injury, skull fracture, or loss of consciousness was seen in 11/15 victims. Ethanol ingestion was detected in blood tests of 10 of the 14 adult victims. Median charges of hospitalization due to a pedicab related injury was US$29,956 ± 77,482. A photographic survey of 50 local pedicabs reveals very limited use of safety belts by passengers despite existing city ordinances.Conclusions
Major trauma victims of pedicab incidents in the United States suffer significant injuries and death. Most cases occurred in passengers falling from the pedicab at night after alcohol ingestion. There is an opportunity for implementation of strategies toward improved injury prevention with this new form of transport. 相似文献220.
Jay N. Meegoda Wiwat Kamolpornwijit 《Frontiers of Environmental Science & Engineering in China》2011,5(2):159-166
As species we humans generate excessive amounts of waste and hence for sustainability we should explore innovative ways to
recover them. The primary objective of this study is to demonstrate an efficient and optimum way to recover chromium and iron
from chromite ore processing residues (COPR) for the production of chrome steel and stainless steel. In Hudson County, New
Jersey, there are more than two million tons of leftover COPR. Part of COPR was used as fill materials for construction sites,
which spread the problem to a larger area. With high solubility along with their toxicity leached chromate from COPR is threatening
the environment as well as human health. In this research, COPR was thermally treated to recover iron with chromium by applying
techniques used in steel manufacturing. An extensive experimental program was performed using a Thermo-Gravimetric Analyzer
(TGA) and bench scale tests to thermally treat the processed chromium contaminated soils with carbon and sand at varying temperatures
and under reducing environment. The optimum chemical composition of COPR and additives to be used in the melts were evaluated
based upon the thermodynamic properties of the mixture to ensure good phase separation, least amounts of iron and chromium
oxides in the slag and minimum variability of final product (steel or iron with chromium). The impact of other oxides on the
steel making process was evaluated to minimize the adverse impact on the process. The research demonstrated the feasibility
of recovering a valuable construction material (chrome steel) from a waste (COPR). 相似文献