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51.
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   

52.
Assessment of aquatic macroinvertebrates is a critical component of many watershed monitoring programs and passive samplers are often used to collect long-term site data, especially in environments where active sampling is not possible. However, standard passive samplers can be expensive and lost in extreme conditions. We developed a sampler using plastic soda bottles (PSB) filled with river rock and compared its effectiveness with standard Hester-Dendy samplers in both lotic and lentic environments. Abundance, taxa richness, and macroinvertebrate composition showed no significant differences between sampler types in either habitat type. PSB samplers, which can be constructed for less than one dollar each, collected the same number of organisms and represented the same diversity as Hester-Dendy devices that cost around $38 each. In studies where funds are limited, PSB samplers appear to be suitable for passive monitoring.  相似文献   
53.
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   
54.
There exist a vast variety of data sources, either manual sources or computerized databases in the field of environmental chemicals. To facilitate the access and to retrieve the information wanted efficiently, we built up two “databanks of data sources”, one called “Databank of Manual Sources (DMAS)” and the other named “Databank of Databases (DADB)”. The set‐up of these databanks is explained and the load status statistics are shown. DMAS has 164 and DADB 106 hits.  相似文献   
55.
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   
56.
Voigt CC  Sörgel K  Dechmann DK 《Ecology》2010,91(10):2908-2917
Flying vertebrates, such as bats, face exceptionally high energy costs during active flapping flight. Once airborne, energy turnover may exceed basal metabolic rate by a factor of up to 15. Here, we asked whether fuel that powers flight originates from exogenous (dietary nutrients), endogenous sources (mostly body lipids or glycogen), or a combination of both. Since most insectivorous bats fly continuously over relatively long time periods during foraging, we assumed that slowly mobilized glycogen, although suitable for supporting brief sallying flights, is inadequate to power aerial insect-hunting of bats. We hypothesized that the insect-feeding Noctilio albiventris rapidly mobilizes and combusts nutrients from insects it has just eaten instead of utilizing endogenous lipids. We used the stable carbon isotope ratio in the bats' exhaled breath (delta13C(brth)) to assess the origin of metabolized substrates of resting and flying N. albiventris in two nutritional conditions: fasted and recently fed. The breath of fasted resting bats was depleted in 13C in relation to their insect diet (delta13C(diet)), indicating the combustion of 13C depleted body lipids. In contrast to this, delta13C(brth) of bats that had recently fed closely matched delta13C(diet) in both resting and flying bats, suggesting a quick mobilization of ingested nutrients for metabolism. In contrast to most non-volant mammals, bats have evolved the ability to fuel their high energy expenditure rates through the rapid combustion of exogenous nutrients, enabling them to conquer the nocturnal niche of aerial insectivory.  相似文献   
57.
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   
58.
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   
59.
Soil-to-plant transfer factors (TFs) of radiocobalt (60Co) were determined in pot experiments for leafy vegetation, root crops and rice grown in the tropical environment of Bangladesh. Soil properties were also measured to establish a relationship between these properties and TF values. Measured TF values of 60Co for leafy vegetation (average of 2.2 x 10(-2)) were slightly higher than the values obtained for root vegetation (average of 1.6 x 10(-2)). However, TF values obtained for rice (average of 1.17 x 10(-2)) were about a factor of 2 lower than the values obtained for leafy vegetation. TF values of 60Co for leafy vegetation and root crops were observed to decrease with increasing pH, exchangeable K+ and clay content in the soil, even though poor correlations were estimated statistically. No consistent relationship between the TF value for 60Co and organic matter content could be deduced. The results presented here provide a useful addition to existing databases on soil-plant transfer for 60Co, since this information is still rather sparse for tropical environments.  相似文献   
60.
Group living is a common strategy among animals and has arisen independently in over 300 species of Lepidoptera. Yet, activity synchrony between individuals is necessary to derive the benefits that ensue from an aggregated lifestyle. Which individuals decide which activities to perform and when to perform them is, therefore, a fundamental question. In some species of social caterpillars and sawflies, the role of a potential behavioral polyethism between individuals has been suggested, whereby certain individuals are consistently more likely to initiate and lead a foraging event. However, in these cases, evidence in support of division of labor is lacking. This study was undertaken to determine if certain individuals of Malacosoma disstria are more likely to be consistent group leaders or if transient leaders could be predicted by the differences in energetic states between individuals. The results of this study indicate that unfed caterpillars initiate foraging bouts and are more likely to lead locomotion. There was no size or sex-based bias in those individuals that acted as temporary leaders. Consistent behavioral differences between individuals, if they exist, are therefore not necessary to explain task allocation and synchronization during foraging in this species.  相似文献   
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