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91.
Phenoloxidase (PO) is a key enzyme involved in the immune response of insects. We show that egg-to-adult exposure to residues of 0.001, but not 0.0005 mg kg−1 ivermectin elevated PO activity in yellow dung flies (Scathophaga stercoraria) developing in cattle dung. Fly fat content was unaffected by the treatments. Therefore, the response of PO was a direct effect of ivermectin and not an indirect one caused by an alteration in body ‘condition’. This supports the non-intuitive conclusion that flies surviving exposure to faecal residues may have enhanced immune function. To our knowledge, this is the first study to assess the effects on PO activity of insecticidal residues in livestock dung. The non-target effects of such residues are of wide interest, given the global use of veterinary products.  相似文献   
92.
93.
Understanding organisation at different social scales is crucial to learning how social processes play a role in sustainable natural resource management. Research has neglected the potential role that individual personality plays in decision making in natural resource management. In the past two decades natural resource management across rural Australia has increasingly come under the direct influence of voluntary participatory groups, such as Catchment Management Authorities. The greater complexity of relationships among all stakeholders is a serious management challenge when attempting to align their differing aspirations and values at four social institutional scales—local, regional, state and national. This is an exploratory study on the psychological composition of groups of stakeholders at the four social scales in natural resource management in Australia. This article uses the theory of temperaments and the Myers-Briggs Type Indicator (MBTI®) to investigate the distribution of personality types. The distribution of personality types in decision-making roles in natural resource management was markedly different from the Australian Archive sample. Trends in personality were found across social scales with Stabilizer temperament more common at the local scale and Theorist temperament more common at the national scale. Greater similarity was found at the state and national scales. Two temperaments comprised between 76 and 90% of participants at the local and regional scales, the common temperament type was Stabilizer. The dissimilarity was Improviser (40%) at the local scale and Theorist (29%) at the regional scale. Implications for increasing participation and bridging the gap between community and government are discussed.  相似文献   
94.
One of the most popular measures of ecological worldview, predicting environmental attitudes and behaviours, is the New Ecological Paradigm (NEP) scale. Since the adoption of the scale for the use among children by Manoli, Johnson and Dunlap in 2007, it has been applied to measure children??s environmental attitudes across cultures. There is however some controversy about the cross-cultural applicability and the relevance of the NEP scale items. The aim of this article is to contribute to the research about environmental views of children from an anthropological view. In the case study, 59 voluntarily participating students aged between ten and 12?years were interviewed in order to learn about their understanding of the NEP items for children. Group discussions were carried out to discover divergent views on the items, followed by in-depth interviews with 15 pupils. The excerpts from these discussions suggest that children experience ambiguity in interpreting the items of the NEP scale. It is concluded that the effective interpretation of scientific facts requires more nuanced and context-specific approach. The author asks for more qualitative, critical probing in addition to the application of the NEP scale in order to get a fuller response and deeper understanding of environmental attitudes of children.  相似文献   
95.
In smelting processes, a large amount of off-gas emission is often generated, which can cause serious environmental and plant hygiene problems if not properly treated. Off-gas cleaning systems extract and treat the hazardous emissions, and ensure that the smelter operation is in accordance with environmental and industrial hygiene regulations. To this end, it is paramount that a well-designed control structure be incorporated into the system. In this work a plantwide control design procedure is applied to an industrial nickel smelter furnace off-gas cleaning system. We first approach the problem by conducting a steady-state analysis based on a nonlinear model of the process, where the objective is to determine how to achieve safe, clean and economic operation in terms of energy consumption. Results reveal that a large amount of energy can be saved by controlling the temperature in the furnace freeboard at its upper bound (active constraint). For the same reason, the temperatures in the two louvers (active constraints) should be controlled at their respective upper bounds so to minimize air intake into the system. The selection of the “unconstrained” variable to be controlled is found by applying the self-optimizing control technique, and the results indicate that a small loss is acceptable when one of the manipulated variables is fixed at its nominal optimal operating point, a highly desirable choice from an operational viewpoint. The bottleneck of the system is identified as the fans' discharge pressures when we allow the feed rate as a degree of freedom. Furthermore, a design change consisting of the installation of an auxiliary air intake in the smelter furnace shows to be a very effective economic alternative to minimize energy consumption. A control structure is then designed where the issue is to keep pressures in the system well within the negative region by determining the configuration of the regulatory and supervisory control layers such that acceptable dynamic performance in face of known, deterministic disturbance is achieved. Nonlinear dynamic simulations are performed to validate the suggested control structure for both modes of operation in the original system and in the proposed design change. The results showed that both regulatory and supervisory designs should make use of the simplicity of decentralized PI control schemes associated with some cascaded configurations so as to boost the disturbance rejection capabilities of the system.  相似文献   
96.
Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well-being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas.  相似文献   
97.
This study aimed to develop a psychometrically sound measure of the construct of love and deep caring for nature as an expression of people’s personal and explicitly emotional relationship with nature. Expert opinion and pre-pilot surveys were employed for refinement of the item pool, and a sample of 307 university students was used in a major pilot study aiming to further purify scale items. A field trial was conducted using a sample of 261 tourists at leisure with nature. The final 15-item Love and Care for Nature (LCN) scale is differentiated from established measures of similar constructs, and demonstrates high internal consistency and sound validity. This research extends the psychological frameworks of environmental altruism, and has also taken the philosophical concept of biophilia, as love for nature, into the operational realm by making it perceptible and measurable.  相似文献   
98.
Alterations to flow regimes for water management objectives have degraded river ecosystems worldwide. These alterations are particularly profound in Mediterranean climate regions such as California with strong climatic variability and riverine species highly adapted to the resulting flooding and drought disturbances. However, defining environmental flow targets for Mediterranean rivers is complicated by extreme hydrologic variability and often intensive water management legacies. Improved understanding of the diversity of natural streamflow patterns and their spatial arrangement across Mediterranean regions is needed to support the future development of effective flow targets at appropriate scales for management applications with minimal resource and data requirements. Our study addresses this need through the development of a spatially explicit reach‐scale hydrologic classification for California. Dominant hydrologic regimes and their physio‐climatic controls are revealed, using available unimpaired and naturalized streamflow time‐series and generally publicly available geospatial datasets. This methodology identifies eight natural flow classes representing distinct flow sources, hydrologic characteristics, and catchment controls over rainfall‐runoff response. The study provides a broad‐scale hydrologic framework upon which flow‐ecology relationships could subsequently be established towards reach‐scale environmental flows applications in a complex, highly altered Mediterranean region.  相似文献   
99.
Mexico City frequently experiences high levels of air pollution. This is due mainly to its topography and meteorology that suppress pollutant diffusion and dispersion. The atmospheric mixing is extremely poor, especially during the dry winter months. The levels of certain pollutants, such as particulate matter, are of concern since they have severe effects on public health. Visibility deterioration is one of the most noticeable effects in large cities. Biological effects of particulate matter on man and animals, ranging from mild eye irritation to death, have been reported. The effects depend on the size of the particles, their solubility, and toxicity. The main objective of this paper is to present the results of a chemical mass balance receptor model applied to a well-characterized data set of particulate matter collected in the Mexico City Metropolitan Area (MCMA). Samples of particulate matter were collected using a denuder and a Hi-Vol system for the respi-rable fraction and total suspended particles, respectively. In this paper the analysis of a database consisting of the chemical composition of 33 samples of respirable particulate matter (aerosols with diameter less than 2.5 µm) is presented. The 12-hour samples were acquired during day and night periods in a typical medium-income neighborhood from December 19, 1989 through February 5, 1990.  相似文献   
100.
ABSTRACT

Non-methane organic compound (NMOC) profiles for on-road motor vehicle emissions were measured in a downtown tunnel and parking garages in Mexico City during 1996. Hydrocarbon samples from the tunnel and ambient air samples (C2-C12) were collected using stainless steel canisters, and carbonyl compounds were collected using 2,4-dinitrophenylhydrazine (DNPH) impregnated cartridges. Canister samples were analyzed by gas chromatog-raphy/flame ionization detection (GC/FID) to ascertain detailed hydrocarbon composition. DNPH samples were analyzed by high performance liquid chromatography (HPLC). NMOC source profiles were quantified for evaporative emissions from refueling, cold start, and hot soak, and on-road operating conditions. The ultimate purpose will be to determine the apportionment of ambient NMOC concentrations using the Chemical Mass Balance (CMB) model. The tunnel profile contained 42.3 ppbC% of alkanes, 20.6 ppbC% of unsaturated compounds, and 22.4 ppbC% of aromatics. The most abundant species were acetylene with 7.22 ppbC%, followed by ipentane with 5.69 ppbC%, and toluene with 5.42 ppbC%. These results were compared with those from studies in the United States. The cold start profile was found to be similar to the tunnel profile, although there were differences in the content of acetylene, isopentane, and oxygenates. The abundance of saturated NMOC in the hot soak profile was similar to gasoline head space profiles; it was also much larger than saturated NMOC in the roadway profile.  相似文献   
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