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31.
Medical error taxonomies are used to report and analyse patient safety incidents. Medical error taxonomies can be generic or domain-specific. In comparing generic and domain-specific medical error taxonomies, the literature compares the information both type of taxonomies classify. There is little evidence the taxonomies have been compared in terms of usability and reliability. Twenty nurses and 21 pharmacists participated in a study comparing the usability and reliability of a generic medical error taxonomy and a medication error taxonomy. The medical error taxonomies utilized were the Patient Safety Event Taxonomy and the NCC MERP Taxonomy of Medication Error. The study found no significant difference in the usability ratings of both taxonomies. The taxonomies required different amount of time to classify patient safety incidents and had significantly different reliability levels. The reliability of the NCC MERP Taxonomy of Medication Error was significantly different when used by nurses and pharmacists. The taxonomy was also preferred by the majority of participants. Some recommendations are made about the design of future medical error taxonomies.  相似文献   
32.
有机氯杀虫剂和多氯联苯(PCB)是环境中普遍而稳固的化合物。现已查明,由于它们从温暖的地区逐渐蒸发出来,并在较冷的地区凝聚下来,因而它们富集在寒冷的环境中。在本研究中,我们的结果是,消融的冰川供给阿尔伯达亚高山带湖泊中的有机氯输入量为50%~97%,而提供的水量为73%。对氚的分析结果表明,在夏季的中、晚期,至少10%的冰川消融物是在1950~1970年期间沉积下来的,这期间它受到有机氯更多的污染。这一发现表明,气候变暖可能会使消融的冰川成为日益增多的淡水污染物来源。由于有机物贫乏的冰川粘土对多氯联苯这样的疏水化合物的吸附能力有限,因此冰川水流带来的有机氯大多呈溶解状态。  相似文献   
33.
Recent studies associate particulate air pollution with adverse health effects; however, the exposure to indoor particles of outdoor origin is not well characterized, particularly for individual chemical species. We conducted a field study in an unoccupied, single-story residence in Clovis, California to provide data and analyses to address issues important for assessing exposure. We used real-time particle monitors both outdoors and indoors to quantify nitrate, sulfate, and carbon particulate matter of particle size 2.5 μm or less in diameter (PM-2.5). The results show that measured indoor ammonium nitrate concentrations were significantly lower than would be expected based solely on penetration and deposition losses. The additional reduction can be attributed to the transformation indoors of ammonium nitrate into ammonia and nitric acid gases, which are subsequently lost by deposition and sorption to indoor surfaces. A mass balance model that accounts for the kinetics of ammonium nitrate evaporation was able to reproduce measured indoor ammonium nitrate and nitric acid concentrations, resulting in a fitted value of the deposition velocity for nitric acid of 0.56 cm s−1. The results indicate that indoor exposure to outdoor ammonium nitrate in Central Valley of California are small, and suggest that exposure assessments based on total particle mass measured outdoors may obscure the actual causal relationships for indoor exposure to particles of outdoor origin.  相似文献   
34.
ABSTRACT

Ultrafine particles (UFPs) pose a human health risk as they can penetrate deep into the respiratory system. The Harvard supersite in Boston, MA provides one of the longest time series of UFP concentrations. This study examined the hypothesis that long-term reductions in PM2.5 mass and sulfur have influenced UFP trends by limiting the ability of UFPs to coagulate onto the accumulation mode via polydisperse coagulation with larger particles. The study used Generalized Additive Models (GAMs) to assess whether changes in PM2.5 mass and sulfur concentrations resulted in smaller than expected (assuming no change in PM2.5 mass or sulfur) decreases in daily UFP trends over the 20-year period from 1999 to 2018. The impact of PM2.5 mass and sulfur changes were represented as UFP penalties. Bootstrapping was applied to calculate standard errors for the different trend and penalty estimates. Results showed that PM2.5 mass and sulfur concentrations declined significantly over the study period. The analysis found an estimated 7.3% (95% CI: 3.5, 11.1%) UFP penalty due to long-term PM2.5 mass trends, and a 9.9% (95% CI: 6.2, 13.7%) UFP penalty due to long-term sulfur trends. Findings from this study suggest that future UFP control efforts should account for the role of PM2.5 mass and sulfur changes.  相似文献   
35.
This study seeks to improve understanding of temperature patterns in reservoir outflows. We examined water temperatures in an irrigation storage reservoir, Island Park Reservoir, and its outflow, Henry’s Fork of the Snake River in eastern Idaho. Our objectives were to (1) quantify the extent to which daily temperature ranges in the reservoir outflow deviated from other reaches of the Henry’s Fork, and (2) test whether the reservoir’s net volume change during the summer — expressed as the volume of water remaining in the reservoir on September 1 — predicted mean summer temperature in the outflow. Two years of temperature data showed dampened diel temperature cycles in the reservoir outflow. Model selection with 17 years of climatic, hydrologic, and reservoir management variables found mean summer temperature in the outflow was best predicted by September 1 reservoir volume and average summer air temperature. Two years of weekly reservoir thermal profiles indicated large changes in reservoir volume eliminated cool hypolimnetic water and encouraged mixing, allowing warm epilimnetic water to be discharged into the outflow. Increases in future drought frequency and severity and increases in summer air temperatures could increase the frequency of occurrence of high mean summertime water temperatures in the outflow. Our study provides important information for local managers by quantifying influences on outflow temperatures and the downstream river ecosystem.  相似文献   
36.
Objective: The objective of this study was to determine the frequency of health care provider (HCP) driving safety/cessation-related anticipatory guidance provision and predictors of driving safety-related anticipatory guidance provision by HCPs.

Methods: HCPs in several central/upper Midwest states were surveyed about frequency of anticipatory guidance provision (n = 265).

Results: More than half of HCPs stated that they frequently or always provide driving safety/cessation-related anticipatory guidance to patients aged 85 or older, 38.7% provided this guidance to patients aged 75 to 84, and 13.7% to patients aged 65 to 74. Predictors of driving safety/cessation-related anticipatory guidance provision differed by patient age. For patients aged 65–74, HCP personal experience with a motor vehicle crash (either the HCP themselves or a friend/family member) was significant in predicting anticipatory guidance provision. However, for patients aged 75 and older, significant predictors included HCP rural practice, HCP age, and percentage of HCP patients who were older adults.

Conclusion: HCP counseling provision related to driving issues differs by patient age and several HCP characteristics, including HCP rurality, age, and personal experience with motor vehicle crashes. Because aging results in physical and mental changes that affect driving and can be identified by HCPs, HCPs are in a position to counsel patients on the potential impacts of aging on the act of driving. Future research should examine the reasons for the differences in anticipatory guidance provision found in this study.  相似文献   

37.
Sexual conflict develops when the optimal reproductive strategy for one sex inflicts fitness costs upon the other sex. Among species with intense within-group feeding competition and high costs of reproduction, females are expected to experience reduced foraging efficiency by associating with males, and this may compromise their reproductive ability. Here, we test this hypothesis in chimpanzees, a species with flexible grouping patterns in which female avoidance of large subgroups has been attributed to their relatively high costs of grouping. In an >11-year study of the Kanyawara community of East African chimpanzees (Pan troglodytes schweinfurthii) in the Kibale National Park, Uganda, the availability of sexually receptive females was a key determinant of the number of males in parties. In turn, females experienced significantly lower C-peptide of insulin levels, indicative of reduced energy balance, during periods when they associated with more males. Female associates did not produce the same negative effect. C-peptide levels positively and significantly predicted female ovarian steroid production, indicating that the costs of associating with males can lead to downstream reproductive costs. Therefore, we conclude that Kanyawara chimpanzees exhibit sexual conflict over subgroup formation, with the large groupings that allow males to compete for mating opportunities inflicting energetic and reproductive costs on females. Because association with males is central to female chimpanzees’ anti-infanticide strategy, and males may confer other benefits, we propose that reproductive success in female chimpanzees hinges on a delicate balance between the costs and benefits of associating with male conspecifics.  相似文献   
38.
Barbeito I  Dawes MA  Rixen C  Senn J  Bebi P 《Ecology》2012,93(2):389-401
Understanding the interplay between environmental factors contributing to treeline formation and how these factors influence different life stages remains a major research challenge. We used an afforestation experiment including 92 000 trees to investigate the spatial and temporal dynamics of tree mortality and growth at treeline in the Swiss Alps. Seedlings of three high-elevation conifer species (Larix decidua, Pinus mugo ssp. uncinata, and Pinus cembra) were systematically planted along an altitudinal gradient at and above the current treeline (2075 to 2230 m above sea level [a.s.l.]) in 1975 and closely monitored during the following 30 years. We used decision-tree models and generalized additive models to identify patterns in mortality and growth along gradients in elevation, snow duration, wind speed, and solar radiation, and to quantify interactions between the different variables. For all three species, snowmelt date was always the most important environmental factor influencing mortality, and elevation was always the most important factor for growth over the entire period studied. Individuals of all species survived at the highest point of the afforestation for more than 30 years, although mortality was greater above 2160 m a.s.l., 50-100 m above the current treeline. Optimal conditions for height growth differed from those for survival in all three species: early snowmelt (ca. day of year 125-140 [where day 1 is 1 January]) yielded lowest mortality rates, but relatively later snowmelt (ca. day 145-150) yielded highest growth rates. Although snowmelt and elevation were important throughout all life stages of the trees, the importance of radiation decreased over time and that of wind speed increased. Our findings provide experimental evidence that tree survival and height growth require different environmental conditions and that even small changes in the duration of snow cover, in addition to changes in temperature, can strongly impact tree survival and growth patterns at treeline. Further, our results show that the relative importance of different environmental variables for tree seedlings changes during the juvenile phase as they grow taller.  相似文献   
39.
Female rhesus macaques exhibit matrilineal dominance structures, and high dominance rank confers fitness benefits across a lifetime and across generations. Rank effects are “inherited” through social processes that are well understood; however, biological mechanisms that might impact these processes are not well known. Recently, it has been shown that prenatal androgens appear to be implicated in supporting dominance rank hierarchies in some mammals. In humans, interindividual differences in the second (index) to fourth (ring) digit ratio (2D:4D) have been linked indirectly to variation in prenatal androgens, with low 2D:4D in both sexes associated with higher inferred prenatal androgen effects. 2D:4D has also been related to dominant social behavior and has been shown to co-vary with social systems across nonhuman primate species. Here, we investigate how 2D:4D co-varies with socially inherited dominance rank in female rhesus macaques. Low 2D:4D was associated with higher-ranking females, while higher 2D:4D was associated with lower-ranking females. Similar relationships were also shown between ranked families within matrilines. This is the first study to show such a relationship between 2D:4D and dominance rank in a nonhuman primate and suggests that prenatal androgen effects could be involved in the maintenance of dominance rank in female cercopithecine primates.  相似文献   
40.
The primary objective of this study was to investigate the relationship of work stress, consisting of role stressors and job insecurity, with safety compliance at work. A secondary objective was to test for the possible moderating effect of individual employees’ coping behaviour between experienced work stress and job insecurity, and their safety compliance. A cross-sectional survey design was used (n?=?771). An electronic survey, with a biographical questionnaire and scales on role conflict, role ambiguity, role overload, job insecurity, coping and safety compliance at work, was administered. The results indicated that specific aspects of work stress, notably role conflict, role ambiguity and quantitative job insecurity, and of coping, namely an avoidance style and changing the situation, were important in understanding safety compliance. A moderating effect of avoidance coping was also found.  相似文献   
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