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51.
The present global environmental crisis is demanding serious rather than superficial changes within the cultural assumptions of human-to-human and human-to-nature relationships. In this sense, education is one of the strongest tools to model our future and a key factor of cultural change. One of the principal aims of Education for Sustainable Development (ESD) is to develop cognitive and affective skills that affect people's values, such as empathy and critical thinking. Together with compromise and responsibility towards a group, it is possible to build new values and ways to interact with both people and the environment. In the present study we used positive psychology principles in creating teaching interventions to empower empathy and critical thinking through an ESD programme at a Chilean primary school. The results show that an intervention of this kind helps to harmoniously build reflective thinking and empathy within students. This enables them to achieve important changes in their disposition to make sound personal and environmental decisions, and prepares them to positively meet imposing present and future challenges.  相似文献   
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Black carbon (BC), a constituent of particulate matter, is emitted from multiple combustion sources, complicating determination of contributions from individual sources or source categories from monitoring data. In close proximity to an airport, this may include aircraft emissions, other emissions on the airport grounds, and nearby major roadways, and it would be valuable to determine the factors most strongly related to measured BC concentrations. In this study, continuous BC concentrations were measured at five monitoring sites in proximity to a small regional airport in Warwick, Rhode Island from July 2005 to August 2006. Regression was used to model the relative contributions of aircraft and related sources, using real-time flight activity (departures and arrivals) and meteorological data, including mixing height, wind speed and direction. The latter two were included as a nonparametric smooth spatial term using thin-plate splines applied to wind velocity vectors and fit in a linear mixed model framework. Standard errors were computed using a moving-block bootstrap to account for temporal autocorrelation. Results suggest significant positive associations between hourly departures and arrivals at the airport and BC concentrations within the community, with departures having a more substantial impact. Generalized Additive Models for wind speed and direction were consistent with significant contributions from the airport, major highway, and multiple local roads. Additionally, inverse mixing height, temperature, precipitation, and at one location relative humidity, were associated with BC concentrations. Median contribution estimates indicate that aircraft departures and arrivals (and other sources coincident in space and time) contribute to approximately 24–28% of the BC concentrations at the monitoring sites in the community. Our analysis demonstrated that a regression-based approach with detailed meteorological and source characterization can provide insights about source contributions, which could be used to devise control strategies or to provide monitor-based comparisons with source-specific atmospheric dispersion models.  相似文献   
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Effect of Hunting in Source-Sink Systems in the Neotropics   总被引:3,自引:0,他引:3  
Abstract: Previous studies of the sustainability of wildlife hunting in the Neotropics have not considered the potential dispersal of animals into hunted areas. A literature review of studies of subsistence hunting in the Neotropics suggests that hunting is often conducted in areas adjacent to relatively undisturbed habitat that may act as sources of animals for the hunted sites. We compared studies of tapir (   Tapirus terrestris ) hunting at different sites to illustrate the potential bias of sustainability evaluations based on local productivity. The limited information available suggests that dispersal could have a key role in rebuilding animal populations depleted by hunting. Thus, factors that strongly affect dispersal—such as spatial distribution and size of areas with and without hunting, population size in source areas, and social behavior—should be considered when the sustainability of hunting is evaluated in areas with heterogeneous hunting pressure. We suggest the application of two models that use spatial controls (recognizing the potential source-sink nature of some hunted systems and protecting unhunted refugia) to avoid wildlife overexploitation when biological data and enforcement capabilities to regulate harvests are limited. This approach may produce more reliable evaluations of sustainability, provide information on the dynamics of hunting systems, and help local communities and policymakers conserve key areas (including protected areas) that may act as game sources.  相似文献   
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Safe animal by-product disposal is a priority target as a result of the Bovine Spongiform Encephalopathy crisis in the European beef industry. One such disposal option is the incineration of by-product material such as meat and bone meal residues (MBM) for the purpose of energy recovery. Although currently applied, the thermal decomposition of MBM wastes has not been scientifically studied until now. A series of experiments has been performed to study the thermal behavior of MBM both in inert (N2) and reactive atmosphere (air), both by thermogravimetry and in a horizontal laboratory furnace. As a general trend, MBM gives low PCDD/F values, compared with incineration of other wastes. Maximum yield of pollutants is observed at a nominal temperature between 700 and 800 degrees C.  相似文献   
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We report a case of fetal hydrocephalus secondary to a third ventricle choroid plexus papilloma detected by ultrasound at 33 weeks' gestation. The prenatal sonographic and colour flow Doppler findings of this rare fetal intracranial tumour are discussed.  相似文献   
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T 《Ambio-人类环境杂志》2003,32(8):533-538
森林反射系数模型有助于林区上空卫星图像的判读.本文简要描述了一种多目标森林反射系数模型及其基本思路、模型输入和输出选项.通过以下模拟实例,论证了在森林遥感中运用该模型的可能性:森林反射系数对年龄的依从关系、森林反射系数的季节变化、落叶对森林反射系数的影响、叶绿素和水分指数的敏感性(分别关于叶片中叶绿素和水分),以及由于林分参数的变化而产生的指数的不确定性.如果与大气辐射传送和传感器校准模型一起使用,森林反射系数模型可应用于卫星图像辅助森林生态学和健康评价、森林清查及经营.  相似文献   
60.
Evidence from different chickadee species (Poecile genus) indicates that birds can modify the note composition of their “chick-a-dee” calls in the presence of predator stimuli. Here, we tested the effects of predator models and the distance of those models on calls of three species foraging together at feeding stations: Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor), both members of the Paridae family, and white-breasted nuthatches (Sitta carolinensis), a member of the Sittidae family. Model and distance affected seed-taking rates in all three species. “Chick-a-dee” calling rates were higher in the predator context for both chickadees and titmice, but we detected no predator context effects on “quank” call rates for nuthatches. Predator and distance contexts affected acoustic parameters of notes of the “chick-a-dee” calls of chickadees and titmice; no such effects were detected for nuthatch “quank” calls. These results suggest species differences in encoding of information in the primary social calls of these three species that commonly occur in multi-species flocks. Chickadees and titmice are “nuclear” species and nuthatches are “satellite” species, and these different roles might be related to the differences in vocal signaling that we detected.  相似文献   
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