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1.
通过大量的调研数据对比,详细研究了苏州青少年活动中心的建筑节能工艺,分析了其设计中体现的节能、技术与形式等,研究了其对环境保护所带来的积极有益的启示,探究了现代材料、节能技术等在建筑设计中的价值,以寻求人、建筑、环境三者之间的和谐共生。  相似文献   
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Bursaphelenchus xylophilus is considered the most dangerous quarantine pest in China. It causes enormous economic and ecological losses in many countries from Asia and Europe. The glycoside hydrolase 45 gene family has been demonstrated in early studies to contribute to the cell wall degradation ability of B. xylophilus during its infection. However, the copy number variation (CNV) of the GH45 gene and its association with B. xylophilus pathogenicity were not fully elucidated. In this study, we found that the GH45 gene with two copies is the most predominant type among 259 B. xylophilus strains collected from China and Japan. Additionally, 18 strains are identified as GH45 genes with a single copy, and only two strains are verified to have three copies. Subsequent expression analysis and inoculation test suggest that the copy numbers of the GH45 gene are correlated with gene expression as well as the B. xylophilus pathogenicity. B. xylophilus strains with more copies of the GH45 gene usually exhibit more abundant expression and cause more severe wilt symptoms on pine trees. The aforementioned results indicated the potential regulatory effects of CNV in B. xylophilus and provided novel information to better understand the molecular pathogenesis of this devastating pest.  相似文献   
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In this paper, a high-temperature proton-exchange membrane fuel cell (HT-PEMFC) system using fluorine-containing polybenzimidazole (6FPBI) composite membranes doped with cross-linkable polymer ionic liquid (cPIL) is developed and studied. The reliability of the model is verified by a comparison with the experimental data. The performance of the HT-PEMFC system using 6FPBI membranes with different levels of cPIL is analyzed. The results show that when the HT-PEMFC uses 6FPBI membranes with a cPIL content of 20 wt % (6FPBI-cPIL 20 membranes), the single cell power density is 4952.3 W·m2. The excessive cPIL content will lead to HT-PEMFC performance degradation. The HT-PEMFC system using the 6FPBI-cPIL 20 membranes shows a higher performance, even at higher temperatures and pressures, than the systems using 6FPBI membranes. In addition, the parametric study results suggest that the HT-PEMFC system should be operated at a higher inlet temperature and hydrogen pressure to increase system output power and efficiency. The oxygen inlet pressure should be reduced to decrease the power consumption of the ancillary equipment and improve system efficiency. The proposed model can provide a prediction for the performance of HT-PEMFC systems with the application of phosphoric-acid-doped polybenzimidazole (PA-PBI) membranes.  相似文献   
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Androdioecy is the crucial transition state in the evolutionary direction of hermaphroditism to dioecy, however, the molecular mechanisms underlying the formation of this sex system remain unclear. While popular in China for its ornamental and cultural value, Osmanthus fragrans has an extremely rare androdioecy breeding system, meaning that there are both male and hermaphroditic plants in a population. To unravel the mechanisms underlying the formation of androdioecy, we performed small RNA sequencing studies on male and hermaphroditic O. fragrans. A total of 334 miRNAs were identified, of which 59 were differentially expressed. Functional categorization revealed that the target genes of differentially expressed miRNAs were mainly involved in the biological processes of reproductive development and the hormone signal transduction pathway. We speculated that the miRNA160, miRNA167, miRNA393 and miRNA396 families may influence the sex differentiation in O. fragrans. Overall, our study is the first exploration of miRNAs in the growth and development process of O. fragrans, and is also the first study of androdioecious plants from the miRNA sequencing perspective. The analysis of miRNAs and target genes that may be involved in the sex differentiation process lay a foundation for the ultimate discovery of the androdioecious molecular mechanism in O. fragrans.  相似文献   
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Surveillance, now a commonplace phenomenon in everyday life, has been explored from various disciplines over three decades. Today's surveillance practices depend primarily upon many software technologies that collect, store and process personal data for the purposes of influence, management, protection or detection. The identification and categorisation of data have thus emerged as the technical signature of surveillance. An individual has many identities belonging to different contexts of his/her life, but in this paper, we explore the relationship between surveillance and identity in virtual contexts only. We argue that an understanding of identity purely as data is fundamental to understanding surveillance. We propose abstract general definitions of surveillance and identity that together create a conceptual framework, capturing key features common to many disparate surveillance situations. Our work concludes that the essence of surveillance is that of a surveillance context, which is precisely and solely defined by the availability of data about the behaviour and identity of its entities. The data that distinguishes the entities of the context we call identifiers; we explore the creation, provenance, comparison and transformation of identifiers. Abstractly, surveillance is a process that tests for properties of data, and sorts identifiers into categories.  相似文献   
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