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141.
基于工作流引擎的科研审批流程的设计与实现 总被引:1,自引:0,他引:1
卓皓 《中国教育技术装备》2011,(33)
科研一直以来都是高等学校的重点工作之一,科研管理信息化也是教育信息化战略的重要组成部分。就高校科研管理系统中最为复杂的审批流程进行分析研究,结合先进的工作流引擎技术来进行具体的设计与实现,使得科研审批流程变得清晰、高效。 相似文献
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信息技术支持下的科学研究性学习:模式、实施与成效——以“数字化微型气象站”在研究性学习中的应用为例 总被引:1,自引:0,他引:1
通过以"数字化微型气象站"在科学研究性学习中的应用为例,探析了运用信息技术开展研究性学习的方式,实施了气象专题系列式的研究性学习,并通过访谈调查法了解学习的成效。调查结果表明,学生在研究性学习中体会到科学研究的过程并获得了积极的情感体验;师生们都对信息技术支持下的科学研究性学习给予了较高地评价。 相似文献
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制造类大企业与技术型小企业协同价值创造策略问题存在深入探究的价值。通过调研归纳出企业协同价值创造行为过程框架,建立企业协同价值创造初始过程的策略选择两阶段Stackelberg博弈模型,通过最优化问题的求解探讨博弈主体的策略优化问题。结果表明,大企业的技术创新意向投入存在阈值,且平均机会成本对该阈值有正向影响,大企业的技术创新成本参数与技术服务合同违约金系数对创新意向投入有负向影响;大企业的技术创新意向投入、渠道概率、意向概率,以及违约金系数对小企业的技术服务营销管理投入有正向影响,平均机会成本对技术服务营销管理投入有负向影响。数值仿真分析验证了研究命题与模拟结果的一致性。 相似文献
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Dong-Dong Wu Cui-Ping Yang Ming-Shan Wang Kun-Zhe Dong Da-Wei Yan Zi-Qian Hao Song-Qing Fan Shu-Zhou Chu Qiu-Shuo Shen Li-Ping Jiang Yan Li Lin Zeng He-Qun Liu Hai-Bing Xie Yun-Fei Ma Xiao-Yan Kong Shu-Li Yang Xin-Xing Dong Ali Esmailizadeh David M Irwin Xiao Xiao Ming Li Yang Dong Wen Wang Peng Shi Hai-Peng Li Yue-Hui Ma Xiao Gou Yong-Bin Chen Ya-Ping Zhang 《国家科学评论(英文版)》2020,7(6):952
Abundant and diverse domestic mammals living on the Tibetan Plateau provide useful materials for investigating adaptive evolution and genetic convergence. Here, we used 327 genomes from horses, sheep, goats, cattle, pigs and dogs living at both high and low altitudes, including 73 genomes generated for this study, to disentangle the genetic mechanisms underlying local adaptation of domestic mammals. Although molecular convergence is comparatively rare at the DNA sequence level, we found convergent signature of positive selection at the gene level, particularly the EPAS1 gene in these Tibetan domestic mammals. We also reported a potential function in response to hypoxia for the gene C10orf67, which underwent positive selection in three of the domestic mammals. Our data provide an insight into adaptive evolution of high-altitude domestic mammals, and should facilitate the search for additional novel genes involved in the hypoxia response pathway. 相似文献
147.
Jing-Yang Hu Zi-Qian Hao Laurent Frantz Shi-Fang Wu Wu Chen Yun-Fang Jiang Hong Wu Wei-Min Kuang Haipeng Li Ya-Ping Zhang Li Yu 《国家科学评论(英文版)》2020,7(4):798
Pangolins are among the most critically endangered animals due to heavy poaching and worldwide trafficking. However, their demographic histories and the genomic consequences of their recent population declines remain unknown. We generated high-quality de novo reference genomes for critically endangered Malayan (Manis javanica, MJ) and Chinese (M. pentadactyla, MP) pangolins and re-sequencing population genomic data from 74 MJs and 23 MPs. We recovered the population identities of illegally traded pangolins and previously unrecognized genetic populations that should be protected as evolutionarily distinct conservation units. Demographic reconstruction suggested environmental changes have resulted in a population size fluctuation of pangolins. Additionally, recent population size declines due to human activities have resulted in an increase in inbreeding and genetic load. Deleterious mutations were enriched in genes related to cancer/diseases and cholesterol homeostasis, which may have increased their susceptibility to diseases and decreased their survival potential to adapt to environmental changes and high-cholesterol diets. This comprehensive study provides not only high-quality pangolin reference genomes, but also valuable information concerning the driving factors of long-term population size fluctuations and the genomic impact of recent population size declines due to human activities, which is essential for pangolin conservation management and global action planning. 相似文献
148.
Yanhua Qu Chunhai Chen Ying Xiong Huishang She Yong E Zhang Yalin Cheng Shane DuBay Dongming Li Per G P Ericson Yan Hao Hongyuan Wang Hongfeng Zhao Gang Song Hailin Zhang Ting Yang Chi Zhang Liping Liang Tianyu Wu Jinyang Zhao Qiang Gao Weiwei Zhai Fumin Lei 《国家科学评论(英文版)》2020,7(1):113
Known as the ‘third polar region’, the Qinghai-Tibet Plateau represents one of the harshest highland environments in the world and yet a number of organisms thrive there. Previous studies of birds, animals and humans have focused on well-differentiated populations in later stages of phenotypic divergence. The adaptive processes during the initial phase of highland adaptation remain poorly understood. We studied a human commensal, the Eurasian Tree Sparrow, which has followed human agriculture to the Qinghai-Tibet Plateau. Despite strong phenotypic differentiation at multiple levels, in particular in muscle-related phenotypes, highland and lowland populations show shallow genomic divergence and the colonization event occurred within the past few thousand years. In a one-month acclimation experiment investigating phenotypic plasticity, we exposed adult lowland tree sparrows to a hypoxic environment and did not observe muscle changes. Through population genetic analyses, we identified a signature of polygenic adaptation, whereby shifts in allele frequencies are spread across multiple loci, many of which are associated with muscle-related processes. Our results reveal a case of positive selection in which polygenic adaptation appears to drive rapid phenotypic evolution, shedding light on early stages of adaptive evolution to a novel environment. 相似文献
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