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51.
Type A behavior dimensions and optimism were examined as predictors of health and performance. In addition, this research also explored the ways that Type As and optimists cope with stressful situations. The achievement striving dimension of the Type A behavior pattern and optimism were positively related to class performance, while the anger/hostility dimension was positively related to the health symptom of anxiety. Optimism, on the other hand, was negatively related to anxiety. The interaction of achievement striving and optimism was negatively related to anxiety. Additionally, while achievement striving was positively related to problem-focused coping, irritability showed a negative association with problem-focused coping strategy. The results of this study provide insights for both individuals and organizations regarding how to cope with daily stresses in order to lower health risks and improve performance.  相似文献   
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PROBLEM: Although personality characteristics such as impulsiveness have been linked to the driving safety and driving habits of young and middle-aged adults, little research has focused on the role of personality in older driver behavior. METHOD: Using the IVE questionnaire in an exploratory study, three personality dimensions (impulsiveness, venturesomeness, and empathy) were measured in 305 older drivers (ages 57-87 years old). In addition, the Driving Habits Questionnaire was used to estimate driving exposure, and the Driver Behavior Questionnaire (DBQ) was used to estimate driving errors and violations. State-recorded crash data were made available by the state public safety agency. RESULTS: Subjects who reported four or more driving errors had higher impulsivity and empathy scores and lower venturesomeness scores. Subjects reporting driving violations were more likely to have high impulsivity scores. Driving six or more places per week was associated with lower levels of impulsivity. IMPACT: These results suggest that a comprehensive understanding of driving problems among older adults should also include a consideration of personality dimensions. In doing so, the challenges faced in the interpretation of self-report instruments on driving behaviors must be acknowledged, with a move in research toward greater reliance on more objective measures of driving behavior when assessing the impact of personality variables.  相似文献   
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We studied the effects of spatial and temporal timber harvesting constraints on competing objectives of sustaining wildlife habitat supply and meeting timber harvest objectives in a boreal mixedwood forest. A hierarchical modeling approach was taken, where strategic and tactical level models were used to project blocking and scheduling of harvest blocks. Harvest block size and proximity, together with short- and long-term temporal constraints, were adjusted in a factorial manner to allow creation of response–surface models. A new measure of the habitat mosaic was defined to describe the emergent pattern of habitat across the landscape. These models, together with multiple linear regression, were used to provide insight on convergence or divergence between spatial objectives. For example, green-up delay (defined as time required before a harvest block adjacent to a previously logged block can be scheduled for harvest) had an adverse effect on the amount of annual harvest area that could be allocated and blocked spatially, and habitat supply responded in an opposite direction to that of wood supply, where caribou, moose wintering, and marten habitat supply increased when harvest blocks were further apart, maximum block size smaller, and both a green-up delay and mesoscale stratification were applied. Although there was no solution space free of conflicts, the analysis suggests that application of the mesoscale stratification, together with a diversity of harvest block sizes and a between-harvest block proximity of 250 m, will perform relatively well with respect to wood supply objectives, and at the same time create a less fragmented landscape that better reflects natural forest patterns.  相似文献   
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This paper reports the development of the Career–Family Attitudes Measure (CFAM), a new 56-item instrument for measuring individuals' attitudes towards managing the career and family interface. The measure was administered to a large sample of high school students and factor analyzed to reveal six dimensions of career and family attitudes, which were then scaled. Females in the sample had significantly more positive attitudes towards Balance and Independence than did males, while males had significantly more positive attitudes towards Dominance and Spousal Support than did females. Antecedents such as parental employment history and educational aspirations were significantly related to several of the scales. Results indicated that career–family attitudes involve preferences for the integration of career and family rather than for trade-offs between them. Research to establish the validity and explore the many applications of the CFAM is needed. © 1998 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT

In population exposure studies, personal exposure to PM is typically measured as a 12- to 24-hr integrated mass concentration. To better understand short-term variation in personal PM exposure, continuous (1-min averaging time) nephelometers were worn by 15 participants as part of two U.S. Environmental Protection Agency (EPA) longitudinal PM exposure studies conducted in Baltimore County, MD, and Fresno, CA. Participants also wore iner-tial impactor samplers (24-hr integrated filter samples) and recorded their daily activities in 15-min intervals. In Baltimore, the nephelometers correlated well (R2 = 0.66) with the PM25 impactors. Time-series plots of personal nephelometer data showed each participant's PM exposure to consist of a series of peaks of relatively short duration. Activities corresponding to a significant instrument response included cooking, outdoor activities, transportation, laundry, cleaning, shopping, gardening, moving between microenvironments, and removing/putting on the instrument. On average, 63-66% of the daily PM exposure occurred indoors at home (about 2/3 of which occurred during waking hours), primarily due to the large amount of time spent in that location (an average of 7277%). Although not a reference method for measuring mass concentration, the nephelometer did help identify PM sources and the relative contribution of those sources to an individual's personal exposure.  相似文献   
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ABSTRACT

Particulate matter (PM) exposure data from the U.S. Environmental Protection Agency (EPA)-sponsored 1998 Baltimore and 1999 Fresno PM exposure studies were analyzed to identify important microenvironments and activities that may lead to increased particle exposure for select elderly (>65 years old) subjects. Integrated 24-hr filter-based PM2.5 or PM10 mass measurements [using Personal Environmental Monitors(PEMs)] included personal measurements, indoor and outdoor residential measurements, and measurements at a central indoor site and a community monitoring site. A subset of the participants in each study wore passive nephelometers that continuously measured (1-min averaging time) particles ranging in size from 0.1 to ~10 um. Significant activities and locations were identified by a statistical mixed model (p < 0.01) for each study population based on the measured PM2.5 or PM10 mass and time activity data. Elevated PM concentrations were associated with traveling (car or bus), commercial locations (store, office, mall, etc.), restaurants, and working.

The modeled results were compared to continuous PM concentrations determined by the nephelometers while participants were in these locations. Overall, the nephelometer data agreed within 6% of the modeled PM2.5 results for the Baltimore participants and within ~20% for the Fresno participants (variability was due to zero drift associated with the nephelometer). The nephelom-eter did not agree as well with the PM10 mass measurements, most likely because the nephelometer optimally responds to fine particles (0.3–2 um). Approximately one-half (54 ± 31%; mean ± standard deviation from both studies) of the average daily PM2.5 exposure occurred inside residences, where the participants spent an average of 83 ± 10% of their time. These data also showed that a significant portion of PM2.5 exposure occurred in locations where participants spent only 4–13% of their time.  相似文献   
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This research examines the relations of the cognitive factors of beliefs and fears proposed by Price (1982) with the revised Jenkins Activity Survey (JAS) factors of achievement striving and impatience-irritability as well as the outcome measures of job and class performance. Results provide support for Spence, Helmreich, and Pred (1987), and Spence, Pred, and Helmreich's (1989) findings of the positive association between achievement striving and class performance but provide limited support for Price's (1982) model.  相似文献   
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