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The purpose of this study is to evaluate cost-effective reduction strategies for nitrogen oxides (NO x ) in the Asian region. The source-receptor relationships of the Lagrangian “puff” model of long-range transportation, ATMOS-N, were used to calculate the wet/dry deposition of the nitrogen (N) in Asia. Critical loads of N deposition in Asia were calculated from the relationships between the critical load of sulfur (S) and balance of N in and out using the data of S critical load of RAINS-ASIA. The cost functions of N reduction of Asian countries were derived by the regression analysis with the data of cost functions of European countries used in RAINS. In order to assess the environmental impact, the gaps between N deposition and critical load of N were calculated. The emission of NO x was reduced in some cases of this model, and the changes of gaps between N deposition and critical load were observed as well as the changes of the reduction cost. It is shown that a uniform reduction of NO x emissions by countries in Asia is not cost-effective strategy.  相似文献   
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Fine particulatematter (PM2.5) is associated with increased risks of Alzheimer’s disease (AD),yet the toxicologicalmechanisms of PM2.5 promoting AD remain unclear. In this study,wildtype and APP/PS1 transgenic mice (AD mice) were exposed to either filtered air (FA) or PM2.5 for eight weeks with a real-world exposure system in Taiyuan, China (mean PM2.5 concentration in the cage was 61 μg/m3). We found that PM2.5 exposure could remarkably aggravate AD mice’s ethological and brain ultrastructural damage, along with the elevation of the pro-inflammatory cytokines (IL-6 and TNF-α), Aβ-42 and AChE levels and the decline of ChAT levels in the brains. Based on high-throughput sequencing results, some differentially expressed (DE) mRNAs and DE miRNAs in the brains of AD mice after PM2.5 exposure were screened.Using RT-qPCR, seven DEmiRNAs (mmu-miR-193b-5p, 122b-5p, 466h-3p, 10b-5p, 1895, 384–5p, and 6412) and six genes (Pcdhgb8, Unc13b, Robo3, Prph, Pter, and Tbata) were evidenced the and verified. Two miRNA-target gene pairs (miR-125b-Pcdhgb8 pair and miR-466h-3p-IL-17Rα/TGF-βR2/Aβ-42/AChE pairs) were demonstrated that they were more related to PM2.5-induced brain injury. Results of Gene Ontology (GO) pathways and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways predicted that synaptic and postsynaptic regulation, axon guidance, Wnt, MAPK, and mTOR pathways might be the possible regulatory mechanisms associated with pathological response. These revealed that PM2.5- elevated pro-inflammatory cytokine levels and PM2.5-altered neurotransmitter levels in AD mice could be the important causes of brain damage and proposed the promising miRNA andmRNA biomarkers and potentialmiRNA-mRNA interaction networks of PM2.5-promoted AD.  相似文献   
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Social interactions may shape brain development. In primitively eusocial insects, the mushroom body (MB), an area of the brain associated with sensory integration and learning, is larger in queens than in workers. This may reflect a strategy of neural investment in queens or it may be a plastic response to social interactions in the nest. Here, we show that nest foundresses—the reproductive females who will become queens but are solitary until their first workers are born—have larger MBs than workers in the primitively eusocial sweat bee Augochlorella aurata. Whole brain size and optic lobe size do not differ between the two groups, but foundresses also have larger antennal lobes than workers. This shows that increased neural investment in MBs precedes social group formation. Larger MBs among foundresses may reflect the increased larval nutrition provisioned to future queens and the lack of social aggression from a dominant queen upon adult emergence.

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Drainfields for disposal of septic tank effluents are typically designed by considering the loss of water by either upward evapotranspiration into the atmosphere or lateral and downward absorption into the adjacent soil. While this approach is appropriate for evapotranspiration systems, absorption systems allow water loss by both mechanisms. It was proposed that, in areas where high evapotranspiration rates coincide with permeable soils, drainfield sizes could be substantially reduced by accounting for both mechanisms. A two-year field demonstration was conducted to determine appropriate design criteria for areas typical of the Texas High Plains. The study consisted of evaluating the long-term acceptance rates for three different drainfield configurations: evapotranspiration only, absorption only, and combined conditions. A second field demonstration repeated the experiments for additional observation of the combined evapotranspiration and absorption and achieved similar results as the first study. The field tests indicated that the current design loading criteria may be increased by at least a factor of two for the Texas High Plains region and other Texas areas with similar soil composition and evapotranspiration rates, while still retaining a factor of safety of two.  相似文献   
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Whilst river catchments are axiomatic units to hydrological science, their use as administrative boundaries, even within the water function, is highly dependent upon socio‐political considerations. In moves to accomplish sustainable development, with its emphasis on proactive community procedures, the catchment/basin unit is, however, receiving detailed attention—notably in England/Wales and in Canada. This paper catalogues the patterns and processes of catchment planning on both sides of the Atlantic via case studies in Ontario and southern England (Thames). Conclusions are that scale, tradition (of consultation) and information about land‐use effects on river behaviour are important controls on the rates and styles of implementation.  相似文献   
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Efforts to anticipate threats to biodiversity take the form of species richness predictions (SRPs) based on simple correlations with current climate and habitat area. We review the major approaches that have been used for SRP, species-area curves and climate envelopes, and suggest that alternative research efforts may provide more understanding and guidance for management. Extinction prediction suffers from a number of limitations related to data and the novelty of future environments. We suggest additional attention to (1) identification of variables related to biodiversity that are diagnostic and potentially more predictable than extinction, (2) constraints on species dispersal and reproduction that will determine population persistence and range shifts, including limited sources or potential immigrants for many regions, and (3) changes in biotic interactions and phenology. We suggest combinations of observational and experimental approaches within a framework available for ingesting heterogeneous data sources. Together, these recommendations amount to a shift in emphasis from prediction of extinction numbers to identification of vulnerabilities and leading indicators of change, as well as suggestions for surveillance tools needed to evaluate important variables and the experiments likely to provide most insight.  相似文献   
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