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61.
Much of the literature on stress and organizational outcomes has focused on organizational factors and has ignored extraorganizational stressors that lead to perceived stress. However, research in other fields and recent studies in management suggests that acute‐extraorganizational stressors, such as traumatic events, may have potentially negative and costly implications for organizations. This study tests a theoretical model of traumatic stress and considers the relationship between strain from an acute‐extraorganizational stressor, the terrorist attack on September 11, 2001, and absenteeism. Using a sample of 108 MBA and MPA students, this study suggests that strain caused by an acute‐extraorganizational stressor can have important consequences for organizations. Namely, employees who report more strain from a traumatic life event are more likely to be absent from work in the weeks following the event. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
62.
This study assessed the relationship among land use, riparian vegetation, and avian populations at two spatial scales. Our objective was to compare the vegetated habitat in riparian corridors with breeding bird guilds in eight Rhode Island subwatersheds along a range of increasing residential land use. Riparian habitats were characterized with fine-scale techniques (used field transects to measure riparian vegetation structure and plant species richness) at the reach spatial scale, and with coarse-scale landscape techniques (a Geographic Information System to document land-cover attributes) at the subwatershed scale. Bird surveys were conducted in the riparian zone, and the observed bird species were separated into guilds based on tolerance to human disturbance, habitat preference, foraging type, and diet preference. Bird guilds were correlated with riparian vegetation metrics, percent impervious surface, and percent residential land use, revealing patterns of breeding bird distribution. The number of intolerant species predominated below 12% residential development and 3% impervious surface, whereas tolerant species predominated above these levels. Habitat guilds of edge, forest, and wetland bird species correlated with riparian vegetation. This study showed that the application of avian guilds at both stream reach and subwatershed scales offers a comprehensive assessment of effects from disturbed habitat, but that the subwatershed scale is a more efficient method of evaluation for environmental management.  相似文献   
63.
64.

Energy and environmental issues have triggered the search for new sources of green energy alternatives in recent years. Biofuel production from renewable sources is widely considered one of the most sustainable alternatives for environmental and economic sustainability. Microalgae are currently being promoted as one of the most promising liquid biofuel feedstocks due to their rapid growth, high lipid production capacity, and carbon–neutral cycle. In this study, whole microalgae cells were utilized as raw material to produce solid biofuel, i.e., Bio-Coke, and this study aimed to investigate the possibility of microalgae Bio-Coke as an alternative to coal coke. The results show that Bio-Coke can be produced from microalgae in the temperature range of 80–100 °C. The apparent density is between 1.253 and 1.261 g/cm3, comparable to the apparent density of lignocellulosic Bio-Coke. Additionally, the calorific value is higher than the calorific value of lignocellulosic Bio-Coke and within the range of the calorific value of subbituminous coal. Therefore, microalgae Bio-Coke can be utilized to replace coal coke usage in the future.

  相似文献   
65.
While collating contributions and comments from 36 researchers, the coordinating authors accidentally omitted Dr. Suzanne Carrière from the list of contributing co-authors. Dr. Carrière’s data are described in Tables 1 and 3, Figure 2 and several places in the narrative. The new author list is thus updated in this article.  相似文献   
66.
The public health consequences of extreme heat events are felt most intensely in metropolitan areas where population density is high and the presence of the urban heat island phenomenon exacerbates the potential for prolonged exposure. This research develops an approach to map potential heat stress on humans by combining temperature and relative humidity into an index of apparent temperature. We use ordinary kriging to generate hourly prediction maps describing apparent temperature across the Greater Toronto Area, Canada. Meteorological data were obtained from 65 locations for 6?days in 2008 when extreme heat alerts were issued for the City of Toronto. Apparent temperature and exposure duration were integrated in a single metric, humidex degree hours (HDH), and mapped. The results show a significant difference in apparent temperature between built and natural locations from 3?pm to 7?am; this discrepancy was greatest at 12?am where built locations had a mean of 2.8 index values larger, t(71)?=?5.379, p?<?0.001. Spatial trends in exposure to heat stress (apparent temperature, ≥30°C) show the downtown core of the City of Toronto and much of Mississauga (west of Toronto) as likely to experience hazardous levels of prolonged heat and humidity (HDH?≥?72) during a heat alert. We recommend that public health officials use apparent temperature and exposure duration to develop spatially explicit heat vulnerability assessment tools; HDH is one approach that unites these risk factors into a single metric.  相似文献   
67.
The use of copper-based fungicides leads to an accumulation of copper (Cu) in vineyard soils, potentially causing adverse effects to the microbial function and fertility of the soil. This study used a soil microcosm approach to assess the effects of Cu accumulation on microbial function in vineyard soils. Surface soil samples were collected from 10 vineyards and a number of un-impacted reference sites in each of three different viticultural regions of Australia. The field-collected soils were transferred to microcosms and maintained for up to 93 days in the laboratory at 20–22 °C and 60 % of their maximum water-holding capacity. The microbial function of the soils was indicated by measuring phosphomonoesterase, arylsulfatase, urease, and phenol oxidase activities. In general, the vineyard soils had greater concentrations of Cu and lower enzyme activities than in the reference soils, although a weak negative relationship between Cu and enzyme activity could only be found for phosphomonoesterase activity. The results show that soil physical–chemical properties (i.e., organic carbon, pH) are greater determinants of soil enzyme activity than increased soil Cu concentration at the Cu concentrations present in vineyard soils.  相似文献   
68.
We examined relationships between hepatic concentrations of halogenated organic contaminants and ethoxyresorufin O-deethylase (EROD) activity and retinoid (vitamin A) concentrations in livers, as well as retinol and thyroid hormone (TT3, TT4) levels in blood plasma, of northern fulmars at two breeding colonies in the Canadian High Arctic. Biomarker levels or responses did not differ significantly between males and females at either colony, nor was there any significant difference between colonies. No significant relationships were found between thyroid hormone or hepatic retinoid concentrations and any of the dioxin-like compounds or their Toxic Equivalents (TEQs) although significant positive correlations were found with plasma retinol (p < 0.03). EROD activity was significantly correlated with hepatic dioxin-like compounds and their TEQs (p < 0.001) as well as total PCBs (p < 0.01), which suggests that EROD induction occurs in northern fulmars at environmentally-relevant concentrations.  相似文献   
69.
According to Snyder's hope theory, high hope individuals possess more goal‐related strategies and are more motivated to achieve their goals than their low hope counterparts. Therefore, we examined the relationship between hope and job performance using three different samples of employees of different job levels and industries. We found that more hopeful sales employees, mortgage brokers, and management executives had higher job performance, as measured a year later, even after controlling for their self‐efficacy and cognitive ability. In a fourth study, we examined if more hopeful employees attempt to solve problems differently than do those with less hope. Higher hope management executives produced more and better quality solutions to a work‐related problem, suggesting that hopefulness may help employees when they are confronted with problems and encounter obstacles at work. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
70.
We investigated feedback acceptance by participants (N = 141) in an operational developmental assessment center (AC). Consistent with predictions based on self‐enhancement theory and the Affective Infusion Model, results indicated that higher assessor ratings were associated with higher feedback acceptance, and this relationship was partially mediated by the participant's affective reaction to the feedback session. Participants' self‐ratings of their AC performance did not affect this relationship suggesting no support for our prediction based on self‐verification theory. We also investigated the role of participants' self‐ratings of agreeableness, extraversion, and emotional stability in feedback acceptance by testing specific moderated mediation hypotheses. Extraversion was related to feedback acceptance through the affective reaction to the feedback session. Agreeableness moderated the affective reaction to the feedback session and feedback acceptance relationship such that there was a strong relationship between affective reaction and feedback acceptance for highly agreeable participants, but no relationship for low agreeable individuals. For low agreeable individuals, there was a positive direct relationship between the assessor ratings and feedback acceptance which was not observed for highly agreeable individuals. The hypothesized role of emotional stability in predicting feedback acceptance was not supported. Implications for the delivery of feedback in developmental ACs are discussed in light of these findings. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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