蜂蜡类残留物的科学分析研究

蜂蜡是古代人类可获得的最常见的天然材料之一，在人类生产生活中占有重要地位。对蜂蜡类残留物的科技分析可直接提供古代人类对蜂蜡利用的科学证据。本文介绍了蜂蜡的产生与组成，梳理了蜂蜡类残留物的样品处理与检测分析方法，并总结了蜂蜡类残留物科学鉴定的依据，以期为古代蜂蜡利用与其他相关问题的研究提供有益参考。     

黄河之水天上来

唐代诗人李白以其非凡才华、磅礴气势吟诵":君不见黄河之水天上来,奔流到海不复回",这千古叫绝传世作,令万民向往黄河源。     

迎春·心与倒淌河交响(组诗)

礼赞穿越生命之河 我从青春年少时就在歌吟情有独钟的倒淌河,古稀暮秋时依然如故，让礼赞穿越生命之河,去迎接希望的春天……     

Early history of Chinese domestic sheep indicated by ancient DNA analysis of Bronze Age individuals

China has a long history of sheep husbandry, and has several indigenous sheep breeds. However, the exact geographic origin of Chinese domestic sheep remains unclear. To provide valuable genetic information for origin of Chinese domestic sheep, we performed an ancient DNA study on 22 sheep excavated from four Bronze Age archaeological sites in Northern China. Two lineages (A and B) were observed in ancient Chinese sheep, of which lineage A was predominant reaching a frequency of 95.5%. Furthermore, phylogenetic network showed that the most frequent haplotype in ancient sheep was the founder of lineage A. These results suggest that Lineage A may hold the key to understanding the origin of Chinese domestic sheep. Sequence sharing and principal component analysis showed that the ancient Chinese sheep had a close affinity to modern Chinese sheep. However, there was no significant breed structure among three modern Chinese sheep groups, making it difficult to determine their relationship to ancient Chinese sheep. Lastly, our results imply that ancient DNA analysis could provide a new way to investigate prehistoric East-West contact.     

A Visual Analytics System for Space–Time Dynamics of Regional Income Distributions Utilizing Animated Flow Maps and Rank-based Markov Chains

Regional income convergence and divergence has been an active field of research for more than 20 years, and research papers in this field are still being produced at a prodigious rate. Despite their importance for the study of dynamics of income distribution, interactive visualization tools revealing spatiotemporal dimensions of the income data have been sparsely developed. This study introduces a visual analytics system for the space–time analysis of income dynamics. We use state-level US income data from 1929 to 2009 to demonstrate the visual analytics system and its utility for exploring similar data. The system consists of two modules, visualization and analytics. The visualization module, a Web-based front-end called Rank-Path Visualizer (RPV), draws inspiration from the cartographic technique of flow mapping, originally developed by Tobler and embodied in his canonical Flow Mapper application.     

试论北京地区的新石器时代文化

北京地区处于东北和华北文化区的交汇地带,其新石器时代文化从距今10000多年一直延续到大约距今3800年。除雪山一期文化对外影响稍大外,其余时候并未形成强有力的中心。由于北京地区所具有的边缘地带的特点,使其不时成为多种文化因素汇聚的熔炉,以及联系东北、北方、中原、海岱文化系统的纽带,对"中国相互作用圈"的酝酿、形成和早期发展起到重要的作用。