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241.
Abstract

Carbofuran was applied over seeded rutabaga cv. York and residues (corrected for recovery) of carbofuran, 3‐hydroxy‐ and 3‐ketocarbofuran in the harvested roots averaged 0.15, 0.23 and 0.07 ppm in peel and 0.09, 0.14 and 0.05 ppm in pulp, respectively. Samples were extracted by hot acid digestion, partitioned in methylene chloride and cleaned up on Florisil. The 3‐hydroxy‐carbofuran was ethoxylated and the compounds were converted into their dinitrophenyl ethers and analysed by electron capture gas chromatography using 3% OV‐3 column.  相似文献   
242.
Abstract: Domestic dogs (Canis familiaris) and cats (Felis catus) are the most abundant mammalian carnivores worldwide. Given that domestic carnivores rely on human‐provided food, their densities are usually independent of prey densities. Nevertheless, underfed pets may need to hunt to meet their energetic and nutritional requirements. We explored the effects of different levels of care (provision of food) of dogs and cats on their predation rates on wild vertebrates in 2 areas of southern Chile. We interviewed cat and dog owners and analyzed prey remains in scats of pets to examine how domestic dogs and cats were managed and to gather information on the wild vertebrates killed and harassed by pets. We used logistic regression to examine the association between pet care and the frequency of wild vertebrate remains in scats. The probability of a dog preying on vertebrates was higher for poorly fed than for adequately fed dogs (odds ratio = 3.7) and for poorly fed than for adequately fed cats (odds ratio = 4.7). Domestic dogs and cats preyed on most endemic and threatened mammals present in the study sites. Our results provide support for the hypothesis that the less care domestic animals receive from owners the higher the probability those animals will prey on wild vertebrates.  相似文献   
243.
Since the inception of sustainable development (SD), there has been a somewhat ignored contradiction between paradigms that are ecosystem‐based and paradigms that are human‐based or purely economic. We suggest that this contradiction can be unified through a balance of the two. The Chinese Yin‐Yang philosophy is applied as a tool or approach to seeking balance between these ecocentric and anthropocentric paradigms. Priority education policy design for the merging of ecology and health are projected through an Ecohealth lens in response to increasing SD challenges and the intention of the international Ecohealth organization to contribute to SD goals. Meeting SD goals along the nexus of health and environment is further considered through early‐careerist cultural assessments and projections. The groups considered for their professional image of the future are: members of the Ecohealth Association Student Section and Chinese early‐careerists participating in a related conference. In response to SD goals, a problem‐based learning design is suggested as an education policy priority. Rather than approaching SD as a boolean concept, for example, by either focusing on ecosystem sustainability or economic development, we suggest education policy for programmes and curriculums that will help emerging professionals balance these paradigms, so as to best address national and global challenges.  相似文献   
244.
245.
We evaluate and compare the performance of Bayesian Monte Carlo (BMC), Markov chain Monte Carlo (MCMC), and the Generalized Likelihood Uncertainty Estimation (GLUE) for uncertainty analysis in hydraulic and hydrodynamic modeling (HHM) studies. The methods are evaluated in a synthetic 1D wave routing exercise based on the diffusion wave model, and in a multidimensional hydrodynamic study based on the Environmental Fluid Dynamics Code to simulate estuarine circulation processes in Weeks Bay, Alabama. Results show that BMC and MCMC provide similar estimates of uncertainty. The posterior parameter densities computed by both methods are highly consistent, as well as the calibrated parameter estimates and uncertainty bounds. Although some studies suggest that MCMC is more efficient than BMC, our results did not show a clear difference between the performance of the two methods. This seems to be due to the low number of model parameters typically involved in HHM studies, and the use of the same likelihood function. In fact, for these studies, the implementation of BMC results simpler and provides similar results to MCMC. The results of GLUE are, on the other hand, less consistent to the results of BMC and MCMC in both applications. The posterior probability densities tend to be flat and similar to the uniform priors, which can result in calibrated parameter estimates centered in the parametric space.  相似文献   
246.
A new method for numerically predicting the total sediment load in a river is proposed. The method can be used to predict the total sediment load with information on channel geometry and slope, flow, and bed materials. The conventional method uses a 1D approach that assumes the channel has a wide rectangular shape. However, the proposed method computes depth‐averaged velocity over the width and predicts the total sediment load based on the flow computations. The new method, therefore, is expected to predict better if the flow changes significantly in the lateral direction. The proposed method was applied to three large sand‐bed rivers in Korea, where information is available regarding suspended sediment. Five formulas were tested of use in making total sediment load computations, namely Engelund‐Hansen's, Ackers‐White's, Yang's, Brownlie's, and Karim's formulas. The predicted total sediment loads are compared not only with measured data but also with results calculated using the 1D approach. Discrepancy ratios between the predicted and measured total sediment loads are given and the results are discussed.  相似文献   
247.
This study developed and tested a cross‐level model of the relationship between two components of active learning climate—enactive exploration and guided learning—and employee errors, and the moderating roles of the individual's traits of openness to experience and conscientiousness. The study examined the medical errors made by 142 resident physicians in 22 hospital departments. Results demonstrated significant interactions between climate and traits: when an individual had a low level of the trait of openness to experience, there was a curvilinear relationship between enactive exploration climate and number of errors. With a high level of openness to experience, the enactive exploration climate was positively associated with the number of errors up to a certain point. In addition, when an individual had a low level of conscientiousness, there was a negative association between guided learning climate and number of errors; with a high level of conscientiousness, there was a positive association between guided learning climate and number of errors. Thus, individual performance was better when the climate complemented the individual's lack of a trait. When the level of the individual's trait was high, the climate intensified the already pronounced trait up to an extent that impaired the individual's performance. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
248.
Within the coping literature, researchers have long been interested in identifying ways in which individuals can improve their coping efforts, making them more effective and thereby reducing the harmful effects of stressful encounters. Although Lazarus and Folkman's transactional model has greatly advanced understanding of the coping process, there continues to be methodological and conceptual challenges that have hindered understanding of the mechanisms behind effective coping. Addressing these issues in the use of a novel approach of analyzing variation in coping (i.e., directed coping) at both the coping event and person coping levels, the current study examined the process of coping with work stress and the beneficial coping outcomes associated with using a directed coping strategy. A total of 143 nurses completed up to 12 weekly surveys online, reporting on weekly stressful interpersonal conflicts and how they coped with them. Results from multilevel analyses supported predictions that greater directed coping at both the level of the coping event and person is associated with improvements in occupational health outcomes even after controlling for other coping factors. Implications of these results are discussed in relation to future research on coping effectiveness and workplace applications. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
249.
Wright JW  Davies KF  Lau JA  McCall AC  McKay JK 《Ecology》2006,87(10):2433-2439
The current range of ecological habitats occupied by a species reflects a combination of the ecological tolerance of the species, dispersal limitation, and competition. Whether the current distribution of a species accurately reflects its niche has important consequences for the role of ecological niche modeling in predicting changes in species ranges as the result of biological invasions and climate change. We employed a detailed data set of species occurrence and spatial variation in biotic and abiotic attributes to model the niche of a native California annual plant, Collinsia sparsiflora. We tested the robustness of our model for both the realized and fundamental niche by planting seeds collected from four populations, representing two ecotypes, into plots that fully represented the five-dimensional niche space described by our model. The model successfully predicted which habitats allowed for C. sparsiflora persistence, but only for one of the two source ecotypes. Our results show that substantial niche divergence has occurred in our sample of four study populations, illustrating the importance of adequately sampling and describing within-species variation in niche modeling.  相似文献   
250.
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