Temperature variations on the Tibetan Plateau over the last two millennia

The paleoclimate data recovered from ice cores,tree rings and lake sediments indicate regional features of cfimatic change on the Tibeta n Plateau (TP) during the last 2000 years. The composite temperature reconstructions in-dicate that several main climatic episodes, such as the “LittleIce Age“ between 1400 and 1900, the “Medieval Warm Pe-riod“ in 1150-1400, a less warm period in 800-1100, and an earlier cold period between the 3rd and 5th centuries,occurred in the TP. In addition, temperature varied from region to region. The period from AD 800 to 1100, which waswarm in northeastern TP, was contemporaneous with cool-ing in the western and southern TP. The southern TP ex-perienced warming between 1150 and 1400. For western TP,the δ^18O records of the Guliya ice core indicate that the pe-Hod 1250-1500 witnessed a clear warming. Large-scaletrends in the temperature history from northeastern TP aremore similar to those in eastern China than are the trendsfrom the Guliya ice cap far to the west and southern TP. The most prominent similarities between the temperature varia-tions of the TP and eastern China are such cold phases as 1100-1150, 1500-1550, 1650-1700 and 1800-1850, andthe latter three cold events match with three widespreadg lacial advances which occurred on the TP during the Little Ice A2e.     

Time-division phase modulated single-photon interference in a Sagnac interferometer

We introduce a stable, long-distance singlephoton Sagnac interferometer, which has a balanced configuration to efficiently compensate phase drift caused by change of the fiber-optic path. By using time-division phase modulation, single-photon interference was realized at 1550nm in a 5-km-long as well as 27-km-long Sagnac fiber loops,with a fringe visibility higher than 90% and long-term stability. The stable performance of the single-photon interference indicated that the time-division phase-modulated Sagnac interferometer might readily lead to practical applications in single-photon routing and quantum cryptography.     

Expression of human clotting factor Ⅸ mediated by recom- binant lentiviral vector in cultured cells and hemophilia B mice

To explore the expression of human clotting factor Ⅸ (hFⅨ) cDNA in vitro and the feasibility of gene therapy for hemophilia B mice mediated by recombinant lentiviral vector, a recombinant hFⅨ lentiviral vector driven by ubiquitin-C promoter, FUXW, and by ABP liver specific promoter, FAXW, was constructed respectively. Recombinant lentivirus was harvested from 293T cells by calcium phosphate-mediated transient cotransfection of three plasmids (transgene vector, CMV腞8.2, VSV-G). hFⅨ expression was detected in supernatant of 293T, BHK and L-02 cells infected with FUXW virus, whereas higher expression of hFⅨ levels (630 ng/106 cells/48 h) was detected only in L-02 cells infected with FAXW virus. Serum hFⅨ antigen was detected in all hemophilia B mice treated with FAXW virus by tail vein injection, an efficiency level of hFⅨ was observed (45 ng/mL, approximately 1% of normal human levels), the expression lasted for more than 60 d. The results indicated that HIV-based lentiviral vectors offer a promising approach to the gene therapy of hemophilia B.     

抗HBsAg单链抗体的等电点测定和结构模拟

应用实验生物学和计算生物学方法对重组人源抗HBsAg单链抗体(HBscFv)的部分理化性质和空间结构进行分析．首先应用蛋白质分析软件包Antheprot预测HBscFv等电点，然后等电聚焦测定HBscFv等电点，在此基础上，用神经网络法预测HBscFv二级结构，然后用同源建模的方法，获得HBscFv三级结构．结果发现，HBscFv等电点理论值为8．51，实验值为7．3～8．1；PHDsec结果表明，HBscFv是一种全β蛋白质；三级结构建模表明，HBscFv的VH结构域由9个片层组成，VL结构域由8个片层组成；由于单链抗体的特殊性，三级结构建模无法给出VH与VL结构域之间进一步折叠后形成的结构。     

一种动态载荷的识别方法

提出了一种逆优化系统识别动态载荷的方法。该方法避免了一般载荷识别中频响函数求逆运算中由于矩阵病态而引起的运算及运算失败，从而提高了识别精度，为动态载荷，特别是宽频带、瞬态冲击载荷的识别提供了一种有效途径。     

超声波技术在咸蛋腌制中的应用及其机理初探

通过跟踪检测咸蛋腌制过程中蛋清氯化钠浓度的变化，观察到蛋清粘度对氯化钠进入蛋清的显著作用。利用超声波降低蛋清粘度的特性，把超声波技术应用于咸蛋的腌制，明显促进氯化钠的渗透与扩散，缩短了腌制时间。这一结果从粘度的角度初步揭示了超声波促进咸蛋腌制的机理，为超声技术在咸蛋生产中的应用提供了重要的理论依据。     

测定蛋白质与胆酸盐结合量的方法

介绍一种应用高效液相色谱仪连接示差折射率检测仪测定牛血清白蛋白与脱氧胆酸钠的结合量的简便方法．该法通过凝胶过滤实现脱氧胆酸与蛋白质的结合平衡和脱氧胆酸的分离，根据示差折射率检测仪的读数定量脱氧胆酸钠．应用该法精确测定脱氧胆酸钠与牛血清蛋白结合等温线与已报道的采用其他方法测定的结合等温线相似     

鱼露外加酶工艺的探讨

通过对鱼露外加酸发酵及自然发酵过程中氨基态氮、挥发性盐基氨的分析，可比较出鱼露在外加酶发酵及自然发酵过程中的成分变化．以市售优质天然鱼露作对照，检测外加酶鱼露产品的氨基酸及多肽的组成，得出了外加酶发酵的意义．     

Sr-Nd isotope geochemistry of eolian dust of the arid-semiarid areas in China： Implications for loess provenance and monsoon evolution

Strontium (Sr) is a divalent alkaline earth element. Its ionic radius (0.113 nm) is slightly larger than that of calcium (0.099 nm), and Sr thus substitutes isomor- phously for Ca in many minerals. Neodymium (Nd) is a rare earth element. Its chemical prop…