旅游经济影响评估——线性规划在旅游决策中的运用

本文向旅游规划者提供线性规划模型,将其应用到国家级自然风景区--天柱山所在地潜山县,以此研究旅游发展对经济的影响,并建立一个基准水平作为比较的基础.     

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.     

预防抑或治疗?——1950年代治淮工地上的卫生问题及其解决

1950年启动的淮河治理,是中共建政后实施的首项大型水利工程.水利工地的特殊性以及民工自身条件的影响,使最初的治淮受到各种疾病的困扰.医护人员短缺和经费不足,又使多数病患无法得到有效医治.为了缓解卫生问题给工程造成的不利影响,淮委从提高医疗保障水平和改善工地生活环境等方面予以应对,虽然未能根本上消除卫生隐患,但传染病发病率及其他疾病门诊率的下降,还是令治淮工地的卫生困局渐趋缓解.     

RIMOWA箱子决定旅行

“通常，那些名流贵族、明星权贵们会对我们说，‘我要和家人出去旅行，希望拉上一只RIMoWA的旅行箱……’他们几乎没有什么具体的要求和想法，甚至连箱子的颜色都没有一个明确的概念。但有一点，他们都非常信任工匠们的手艺，知道RIMoWA清楚他们理想中旅行箱的样子。”说起这些“独家故事”，RIMoWA工匠们的优雅、机智中还透露出那么一点点的傲气。