非洲锥虫抗人血清相关基因的进化

抗人血清相关蛋白(SRA)是非洲睡眠病的病原体布氏锥虫罗得西亚亚种抵抗人血清中的锥虫溶解因子溶解的关键蛋白. 该蛋白同时也作为鉴定罗得西亚亚种的重要分子标记. 本研究从锥虫亚属各物种的基因组中克隆出与SRA同源的基因片段SRAbc, 并对其进行了测序和结构分析. 测序结果显示, 各物种之间的SRAbc核酸序列同源性高达82%, 表明SRAbc在锥虫亚属的种类中具有起源相同并相对保守的特性. 由于在罗得西亚亚种内同时存在SRA和SRAbc, 故认为SRAbc可以作为VSG重组的“供体VSG”, 通过复制和插入机制整合表达位点. 在自然选择的压力下, SRAbc 将可能再次进化成有功能的SRA基因.     

抽出处理措施的有效性评价

应用经过拟合的模型,对实例中实施的抽出水处理措施的有效性作了数值模拟分析,结果表明,在模拟时段内场地区碳岩含水层中ＴＣＥ污染羽状体的分布范围及其浓度均有比较明显的减小,去污效率比较理想。已由抽水试验证实,其有利因素之一就是污染含水层介质具有较强的水力传导性,鉴于系统的不确定性,应对抽出处理方案进行多阶段设计。     

山西芮城永乐宫元代天花、藻井研究*

本文以山西芮城永乐宫的元代天花、藻井为主要研究对象，基于 2018 至 2019 年间清华大学进行的实地勘察和三维激光扫描数据采集，记录永乐宫元代小木作的现状信息，分析永乐宫天花、藻井的形制与结构特点及设计尺度规律，并通过比较研究总结永乐宫实例在木构藻井发展脉络中的位置和价值。     

Tycho brahe in china: the Jesuit mission to Peking and the iconography of European instrument-making processes

In the late 1660s, Ferdinand Verbiest, a Flemish Jesuit missionary in Peking, was instructed to re-equip the Imperial Observatory. The new instruments which he caused to be built were modelled neither upon contemporary European prototypes, nor those of traditional Chinese astronomy, but on the pieces in Tycho Brahe's Mechanica, of eighty years before. The Chinese instruments were lavishly illustrated, moreover, in 105 woodcuts that contained detailed representations of their processes of construction. It is argued that these illustrations not only give us valuable insights into what the technical Jesuits did in Peking, but show how sixteenth- and seventeenth-century European craftsmen constructed their instruments, for while the location was Oriental, the technology was Western. They can also give important insights into how Tycho's prototypes had been built, and provide us with useful information regarding European instrument-making technology.     

Biomaterials in the nano-era

This article is a brief summary of my plenary talk at the World Biomaterials Congress in Chengdu, Sichuan, China, June 1-5, 2012. It highlights the trend to design and develop biomaterial implants and devices that are more compact and more efficient, as they ＂shrink＂ from the macro- to the micro- and down to the nano-scale.