PROBLEMS: Limited research is available on the acting (work characteristics) and experienced (perceived stress) workload of nurses. The relationship between risk and protective characteristics of work-related factors and the prevalence of musculoskletal symptoms in different body regions is also unclear. METHODS: The study was a cross-sectional design with 97 female registered nurses working in a hospital setting. Two surveys were used to document the workload exposure of the nurses. One survey consisted of 148 items aimed to measure the acting workload variables from the environment; the other survey included 33 items that were aimed to measure the nurses' experienced workload. The musculoskeletal outcomes were documented with a modified version of the Nordic Musculoskeletal Symptom Survey. RESULTS: Factor analyses revealed three factors that accounted for 56% of the total variance. Factor 1 (i.e., integrated experienced energy replenishment/expenditure) represented the psychological effects of work characteristics, effort, perceived risk, and performance. Factor 2 (i.e., acting energy replenishment/expenditure) consisted of non-physical variables of the work characteristics, while Factor 3 (i.e., acting energy expenditure) included both acting and experienced workload. Logistic regression analyses indicated that Factor 3 was significantly associated with the musculoskeletal symptoms of lower and upper back, hands/wrists, and knees/lower legs (odds ratios > 1.0). Factor 2 was significantly associated with the musculoskeletal symptoms of the upper back and knees/lower legs (odds ratios < 1.0). SUMMARY: Both the acting and experienced workloads exhibited associations with musculoskeletal outcomes in the lower back, upper back, hands/wrists, and knees/lower legs in terms of risk and protective effects. 相似文献
The prediction of the probability of death or injury following the inhalation of a toxic gas or vapour is used in risk analysis. The proportion of a population responding for a given endpoint (e.g. lethality) can be related to the received dose using a probit model. Some of the coefficients in the probit equations are based on data from animal testing. Generally, experimental test animals are bred to exhibit low variability. Animal variability in response to toxic exposures may not adequately represent human variability in response to toxic exposures to the tested chemical. It is suggested that some independently established measure of human variability be used in the formulation of the probit equation constants rather than those that arise solely from the fitting of the animal data. 相似文献
In selecting six keywords from the environmental discourse the authors argue that language's 'double motivation' reveals a dialectical structure through which it simultaneously expresses both a utopian narrative and an ideologically driven myth of totality and consensus. The ambiguity of these keywords is of critical significance to all those involved in the environmental discourse, for without agreement on the meaning of commonly used concepts effective policy development is potentially disabled. The keywords we explore are 'community', 'sustainability', 'globalisation', 'diversity', 'democracy' and 'environment' itself. 相似文献
The fate of 15N-labeled cattle (Bos taurus) urine (52 g N m(-2)), applied to a 0.4-m2 surface area on three dates between May and October to three different pasture soils, was studied using 2-m2 lysimeters. Over a period of two years, the sward recovered most of the 15N, but the amount recovered decreased with application date (62% in spring to 17% in fall). However, N uptake by ryegrass (Lolium perenne L.) in Year 2 showed that some nitrogen came from the previous year's urine application. The largest leaching losses of urine N resulted from the late application date. These losses mainly occurred during the first winter despite the small amount of water drainage. Soil type largely determined 15N losses. The granitic Brunisol was the most freely draining and had the greatest leaching (up to 35% recovery of urinary N). In contrast, leaching in the silty loam Neoluvisol remained under 4% of 15N applied. The Calcosol appeared to be susceptible to all kinds of N losses with intermediate unaccounted-for N pool and leaching fractions and lesser utilization of urinary N by grass. Immobilization in soil organic matter, roots and litter, and stubble pools were not markedly influenced by the date of application or soil type. They amounted to 25 to 33, 2, and 2% of N applied as urine, respectively. In these climatic conditions with moderate drainage, leaching of water poor in quality for nitrate only occurred for late-season grazing or on the granitic Brunisol, which was very vulnerable to leaching. 相似文献
Objective: The adaptive behavior of mobile phone–distracted drivers has been a topic of much discussion in the recent literature. Both simulator and naturalistic studies suggest that distracted drivers generally select lower driving speeds; however, speed adaptation is not observed among all drivers, and the mechanisms of speed selection are not well understood. The aim of this research was to apply a driver behavioral adaptation model to investigate the speed adaptation of mobile phone–distracted drivers.
Methods: The speed selection behavior of drivers was observed in 3 phone conditions including baseline (no conversation) and hands-free and handheld phone conversations in a high-fidelity driving simulator. Speed adaptation in each phone condition was modeled as a function of secondary task demand and self-reported personal/psychological characteristics with a system of seemingly unrelated equations (SURE) accounting for potential correlations due to repeated measures experiment design.
Results: Speed adaptation is similar between hands-free and handheld phone conditions, but the predictors of speed adaptation vary across the phone conditions. Though perceived workload of secondary task demand, self-efficacy, attitude toward safety, and driver demographics were significant predictors of speed adaptation in the handheld condition, drivers' familiarity with the hands-free interface, attitude toward safety, and sensation seeking were significant predictors in the hands-free condition. Drivers who reported more positive safety attitudes selected lower driving speeds while using phones.
Conclusion: This research confirmed that behavioral adaptation models are suitable for explaining speed adaptation of mobile phone distracted drivers, and future research could be focused on further theoretical refinement. 相似文献
Arcadian ideals have long been important in western culture. They underpinned projects for colonial settlement and continue to be manifest today in urban perceptions of rural lifestyle throughout the English speaking world. Results from a study of 58 existing or intending smallholders around Christchurch, New Zealand, highlight the way Arcadian ideals and values motivate people to move to the country, and to remain there. They reveal both similarities and contrasts between contemporary New Zealand ideals of the rural way of life and those reported from North America and Europe, and have a number of practical planning implications. 相似文献
Congenital bronchopulmonary malformations detectable on prenatal ultrasound include cystic adenomatoid malformation (CAM), lobar sequestration, and upper airway atresia. We describe three fetuses with prenatally detected intrathoracic lesions in which the associated pulmonary hyperechogenicity disappeared before delivery. In the first case of pulmonary sequestration, the infant was asymptomatic after birth. However, in a case of CAM and another with laryngeal atresia, respiratory distress developed after delivery, despite recent scans showing apparently normal lung fields. This experience suggests that ultrasonic resolution of hyperechogenic lung lesions in utero does not necessarily indicate resolution of the underlying pathology. 相似文献
Queenless workers of the Cape honeybee (Apis mellifera capensis) can develop into reproductives termed pseudoqueens. Although they morphologically remain workers they become physiologically
queenlike, produce offspring, and secrete mandibular gland pheromones similar to those of true queens. However, after queen
loss only very few workers gain pseudoqueen status. A strong intracolonial selection governs which workers start oviposition
and which remain sterile. The “queen substance”, 9-keto-2(E)-decenoic acid (9-ODA), the dominant compound of the queen's mandibular
gland pheromones, suppresses the secretion of queenlike mandibular gland pheromones in workers. It may act as an important
signal in pseudoqueen selection. By analysing the mandibular gland pheromones of workers kept in pairs, we found that A. m. capensis workers compete to produce the strongest queen-like signal.
Received: 2 July 2000 / Accepted in revised form: 28 July 2000 相似文献