Convergent genomic signatures of high-altitude adaptation among domestic mammals

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.     

Encapsulating metal organic framework into hollow mesoporous carbon sphere as efficient oxygen bifunctional electrocatalyst

Applying metal organic frameworks (MOFs) in electrochemical systems is a currently emerging field owing to the rich metal nodes and highly specific surface area of MOFs. However, the problems for MOFs that need to be solved urgently are poor electrical conductivity and low ion transport. Here we present a facile in situ growth method for the rational synthesis of MOFs@hollow mesoporous carbon spheres (HMCS) yolk–shell-structured hybrid material for the first time. The size of the encapsulated Zeolitic Imidazolate Framework-67 (ZIF-67) is well controlled to 100 nm due to the spatial confinement effect of HMCS, and the electrical conductivity of ZIF-67 is also increased significantly. The ZIF@HMCS-25% hybrid material obtained exhibits a highly efficient oxygen reduction reaction activity with 0.823 V (vs. reversible hydrogen electrode) half-wave potential and an even higher kinetic current density (J_K = 13.8 mA cm⁻²) than commercial Pt/C. ZIF@HMCS-25% also displays excellent oxygen evolution reaction performance and the overpotential of ZIF@HMCS-25% at 10 mA cm⁻² is 407 mV. In addition, ZIF@HMCS-25% is further employed as an air electrode for a rechargeable Zn–air battery, exhibiting a high power density (120.2 mW cm⁻² at 171.4 mA cm⁻²) and long-term charge/discharge stability (80 h at 5 mA cm⁻²). This MOFs@HMCS yolk–shell design provides a versatile method for the application of MOFs as electrocatalysts directly.     

高技术投资项目多目标决策的一种改进模型

高技术投资项目的风险决策在企业投资中具有非常重要的作用,是企业发展的核心和关键。本文提出运用密切值决策模型来解决这一问题,它能够很好地避免人为因素,较文[1]更简便和客观有效,易于推广。     

运用AHP层次分析法评估"民转军"过程中的民营企业风险

根据现阶段我国民营企业的现状,分析了民企在“民转军”过程中存在的管理风险、经营风险和财务风险。随后引入AHP层次分析法建立风险评估模型,结合北京亿美博科技有限公司,对其评估,找到关键风险因素,并针对关键因素给出初步的解决设想。     

关于倡导和强化高校为学生服务的意识和职能的探讨

高校要提高学生管理水平,实现培养现代化高素质人才的目标就必须倡导和强化为学生服务的意识和职能,转变观念,树立以人为本、以学生为中心的学生工作理念,将"管理"目的转换成为学生"服务"的宗旨,创造和谐的管理环境.倡导和强化高校为学生服务的意识和职能势在必行.     

网络时代的大众阅读——"网络阅读"研究综述

网络阅读是一种新型的阅读形式,它也对当今大众阅读习惯和阅读文化带来了种种影响.文章对我国近年来研究"网络阅读"这一主题的文献进行了归纳,综合了若干主流观点,对网络阅读的优劣势进行了详细阐述,同时分析了网络阅读对传统阅读的冲击,较为全面地总结了网络阅读的特点以及发展趋势.     

陈数红玫瑰般耀眼

1995年9月8日,在美国纽约的一间公寓里,中国女作家张爱玲的遗体被人发现.此后的12年中,许多人发现并研究起了张爱玲--她的小说里散发出的旧时的情调,她的发型与旗袍透出的独特的气质,她的身世与婚恋成了人们茶余饭后的谈资.……     

次短路问题算法综述

最短路是指所有路中长度最小者,次短路是指长度比最短路严格大的所有路中的最小者;给出已解决的次短路问题算法,列出尚未解决的次短路问题.     

基于开放获取的高校科研成果知识库构建研究

[目的/意义]旨在研究基于开放获取的高校科研成果知识库的构建.[方法/过程]介绍了开放获取与高校科研成果知识库相融合的基础,论述了基于开放获取的高校科研成果知识库构建要素,在剖析已有开放获取的高校科研成果知识库实例的基础上,提出了创新性的基于开放获取的高校科研成果知识库构建方案.[结果/结论]开放获取有效地促进了高校科...     

面向敦煌壁画的移动视觉搜索模型研究

[目的/意义]保护敦煌文化遗产,为敦煌壁画提供移动视觉搜索服务,以助用户高效、便捷地获取敦煌壁画丰富知识资源。[方法/过程]构建基于BoW的图像底层特征匹配和基于主题标签的高层语义关联的移动视觉搜索模型,用SIFT提取图像局部特征,K-means生成有K个视觉单词组成的视觉词典,计算图像映射到视觉词典的TF-IDF向量,通过内积计算相似度匹配图像并排序;根据图像主题添加语义标签,提取最匹配图像的标签实现语义关联搜索;最后收集1200张敦煌壁画图片验证模型的有效性。[结果/结论]在视觉单词数为1000时BoW+SIFT的图像搜索耗时163ms,且图像大小在0.5-2.5倍范围的准确率在83.7%以上,可有效搜索主题语义关联图像。