Induction of embryonic stem cells to hematopoietic cells in vitro

In order to get hematopoietic cells from embryonic stem (ES) cells and to study development mechanisms of hematopoietic cells, the method of inducing embryonic stem cells to hematopoietic cells was explored by differenciating mouse ES cells and human embryonic cells in three stages. The differentiated cells were identified by flow cytometry, immunohistochemistry and Wright's staining. The results showed that embryoid bodies (EBs) could form when ES cells were cultured in the medium with 2-mercaptoethanol (2-ME). However, cytokines, such as stem cell factor (SCF), thrombopoietin (TPO), interleukin-3 (IL-3), interleukin-6 (IL-6), erythropoietin (EPO) and granular colony stimulating factor (G-CSF), were not helpful for forming EBs. SCF, TPO and embryonic cell conditional medium were useful for the differentiation of mouse EBs to hematopoietic progenitors. Eighty-six percent of these cells were CD34+ after 6-d culture. Hematopoietic progenitors differentiated to B lymphocytes when they were cocultured with primary bone marrow stroma cells in the DMEM medium with SCF and IL-6. 14 d later, most of the cells were CD34-CD38+. Wright's staining and immunohistochemistry showed that 80% of these cells were plasma-like morphologically and immunoglubolin positive. The study of hematopoietic cells from human embryonic cells showed that human embryonic cell differentiation was very similar to that of mouse ES cells. They could form EBs in the first stage and the CD34 positive cells account for about 48.5% in the second stage.     

地棘蛙素类似物的CoMFA和CoMSIA的3D-QSAR研究

采用比较分子力场 (CoMFA)分析法和比较分子相似性指标场(CoMSIA)分析法,进行偏最小二乘法(PLS)分析,建立了地棘蛙素类化合物的三维构效模型.通过验证,说明该系列化合物分子立体场、静电场、氢键场和疏水场的分布与生物活性之间有良好的相关性.用模型预测同系列测试集分子,结果与实验值偏差较小.预测结果表明,该力场模型有一定的预测能力.并得出了新的药效团定义模型,可用来指导设计新的地棘蛙素类化合物烟碱型乙酰胆碱配体.     

淫羊藿黄酮治疗骨质疏松的动物实验研究

研究了淫羊藿黄酮(EF)对去卵巢小鼠血清雌二醇(E2)、子宫内膜及骨密度(BMD)的影响.选取36只4月龄的C57雌性小鼠分3组:对照组(假手术组)、模型组(切除双侧卵巢后给予安慰剂)、观察组(切除双侧卵巢后给予EF).于术后4周抽血测雌激素含量,处死后经定量CT测第一腰椎BMD,并切除子宫制备病理切片测量子宫内膜厚度.指标显示:观察组BMD较对照组轻度下降,而模型组BMD较对照组显著下降;模型组及观察组血清E2浓度均较对照组显著下降;子宫内膜厚度两组均较对照组低,但两组间无明显差异.EF可对小鼠卵巢切除后引起的骨质疏松起到有效的预防和治疗作用,但不改变血清E2浓度,不作用于子宫内膜.     

基于生物光敏蛋白细菌视紫红质膜的光子晶体管器件——应用研究

本文利用基于生物光色材料细菌视紫红质（ｂａｃｔｅｒｉｏｒｈｏｄｏｐｓｉｎ，ｂＲ）膜的“光子晶体管”模型进行了光学信息处理方面的应用研究－－在单膜片器件上实现并行非相干光图象相减。     

一个多层次水产养殖信息管理系统的设计

以上海市水产养殖信息管理系统的开发为背景，在确定系统设计目标的基础上，提出了多层次的监管体制，设计了3个监管子系统的实现方案，实现了对上海市水产养殖全过程数字化监控的目标．     

ZnO纳米线的三阶非线性光学性质

用微乳液法制备ZnO纳米线, 对材料的形貌和结构进行透射电镜表征和Raman光谱表征, 并设计超短脉冲Z扫描实验, 研究ZnO纳米线的三阶非线性光学特性. 结果表明：制备的材料尺寸均一、结晶良好, 具有较好的紫外区激子发光特性; ZnO纳米线三阶非线性光学折射率为正值, 其三阶非线性光学极化率比体相ZnO高约3个数量级. 因此制备的ZnO纳米线材料具有较好的光学和非线性光学性质.     

热带西太平洋暖池对中国降水和沿海自然灾害的影响

用暖池指数研究了热带西太平洋暖池对中国降水和沿海自然灾害的影响。结果表明,暖池面积指数对中国降水有一定的预报意义,北界指数对中国长江中下游地区及其他一些地区的降水具有很好的预报性,面积指数与中国沿海台风次数的年际变化呈负相关关系,与1950年以后海冰灾害有明显的相关关系,与灾害性海浪的发生频数关系不大,与海啸的发生有一定的关系。     

基于永续债置换及权益再融资的财务困境纾解方法

针对由流动性不足至清算价值为零所对应的财务困境情境，运用流动性指标与资产存量指标来设定财务困境阈值及破产阈值，综合采用永续债置换及权益再融资的施救策略，构建了该策略下的企业定价模型并进行了实证分析，验证了该综合施救策略的适用性。研究结果表明：适宜的综合采用永续债置换及权益再融资的施救策略有助于企业财务困境的有效纾解，主要依据为：通过债券到期期限的延长，可降低企业的当期还本付息压力，而永续债置换后企业短期流动性压力又得以进一步缓解；在企业资产价值处于一定范围的情境下，综合施救策略能够在确保企业债务价值不减的基础上，实现企业价值、权益价值的增加。     

具有测度积分边界条件的非线性Hadamard分数阶微分方程的正解

使用不动点定理研究一类非线性Hadamard分数阶微分方程正解的存在性，通过适当的非负矩阵来描述非线性的耦合行为，得到具有测度积分边界条件的非线性Hadamard分数阶微分方程正解。给出一个例子，来验证所获得理论结果的有效性和正确性。     

Straightforward Guess and Determine Analysis Based on Genetic Algorithm

With the development of artificial intelligence, the genetic algorithm has been widely used in many fields. In cryptography, the authors find it is natural to code an individual and design its fitness in a genetic algorithm for a straightforward guess and determine analysis (SGDA, in short). Based on this observation, the authors propose an SGDA based on genetic algorithm. Comparing it with the other three SGDAs based on exhaustive search, MILP method and CPP method respectively, the authors illustrate its effectiveness by three stream ciphers: Small scale SNOW 2.0, medium scale Enocoro-128v2 and large scale Trivium. The results show our method is significantly superior to them, especially for Trivium, the method can find a solution of 165 variables in less than one hour, while the other three methods are not applicable due to its enormous search space of size 2^619.37. As far as we know, it is a best solution in an SGDA for Trivium so far.