拟南芥花粉表面蛋白质数据的整合

花粉表面蛋白质参与花粉与柱头的识别,在植物繁殖生长过程中起着重要的作用．以拟南芥为研究对象,通过文献和网络资源的查阅收集其他植物的花粉表面蛋白质的信息,并利用同源性分析,将其转化为拟南芥的花粉表面蛋白相关信息;并将这些数据和拟南芥中已知及可能的花粉表面蛋白质数据整合在一起．然后,对整合的所有蛋白质进行了功能分类和表达分析,并建立了拟南芥花粉表面蛋白质数据库．这对深入研究花粉与柱头识别的分子机理将有重要的促进作用．     

生物有机肥料对落叶松、沙棘育苗地土壤微生态环境的影响研究

在落叶松、沙棘育苗地施用生物有机肥料,以改善其土壤微生态环境,提高落叶松、沙棘育苗成活率,加快落叶松、沙棘苗的生长．试验结果表明：生物有机肥料可以提高红松育苗地的微生物数量,改善pH值、有机质及速效N,P,K等微生态指标,促进落叶松苗和沙棘苗的生长．     

Breast cancer stem cell: the roles and therapeutic implications

Breast cancers have been increasingly recognized as malignancies displaying frequent inter- and intra-tumor heterogeneity. This heterogeneity is represented by diverse subtypes and complexity within tumors, and impinges on response to therapy, metastasis, and prognosis. Cancer stem cells (CSCs), a subpopulation of cancer cells endowed with self-renewal and differentiation capacity, have been suggested to contribute to tumor heterogeneity. The CSC concept posits a hierarchical organization of tumors, at the apex of which are stem cells that drive tumor initiation, progression, and recurrence. In breast cancer, CSCs have been proposed to contribute to malignant progression, suggesting that targeting breast cancer stem cells (BCSCs) may improve treatment efficacy. Currently, several markers have been reported to identify BCSCs. However, there is objective variability with respect to the frequency and phenotype of BCSCs among different breast cancer cell lines and patients, and the regulatory mechanisms of BCSCs remain unclear. In this review, we summarize current literature about the diversity of BCSC markers, the roles of BCSCs in tumor development, and the regulatory mechanisms of BCSCs. We also highlight the most recent advances in BCSC targeting therapies and the challenges in translating the knowledge into clinical practice.     

基于对象存储系统的对象文件系统设计

基于对象文件系统是建立在对象存储系统上的一种应用,它利用对象的特点对数据进行存储和管理．基于对象文件系统由客户端、元数据服务器和基于对象存储设备组成,通过对系统的各部分进行分析,设计并实现了基于对象文件系统．通过对不同文件大小、不同文件分块大小条件下文件系统的性能进行测试分析,找出系统的数据传输瓶颈,使用以对象属性为导向的缓存和预取技术以及聚合读写的方法对文件系统进行了优化．优化后读写吞吐率分别提高了60Mbyte／s和40Mbyte／s。     

基于离散余弦变换的盲水印算法研究

基于离散余弦变换(DCT)方法对水印算法进行了研究,提出一种新的将水印嵌入到分块DCT相位成分的盲水印算法.引入了局部峰值信噪比来确保嵌入水印的不可见性,同时根据混沌系统对初始条件极度敏感的特点,以一维混沌映射的初始条件作为密钥,由产生的混沌序列来确定水印嵌入的子块位置,进而提高算法的安全性.仿真结果表明:采用该算法实现的水印对常见的处理和几何变换具有很好的鲁棒性.     

关于旋转定理的一个证明

在刘礼泉老师参考文献[1]的论文中证明了亚纯星象函数的旋转定理,本文利用类似方法证明1/2阶亚纯星象函数的旋转定理.     

双相不锈钢换热板片回弹变形模拟与实验研究

针对双相不锈钢板片显著回弹变形使得其在可拆卸板式热交换器行业中的开发变得非常困难的问题,采用显/隐式相结合的方法对高强度双相不锈钢FDX27板片进行冲压成形回弹预测.首先,采用显式求解法对板料进行冲压成形分析;其次,移除上下模具后采用隐式求解法对板料的回弹变形进行预测,通过数值模拟对比分析不同模具圆角半径和摩擦系数对F...     

Modeling the Spatial-temporal Characteristics of Mutual Funds' Herd Behavior

Herd behavior in financial markets often leads to unjustified macroscopic phenomena.However,despite existing studies on modeling herd behavior,how it varies acr...     

Seed priming with chitosan improves maize germination and seedling growth in relation to physiological changes under low temperature stress

Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% (w/v) chitosan solutions at 15 °C on the growth and physiological changes were investigated using two maize (Zea mays L.) inbred lines, HuangC (chilling-tolerant) and Mo17 (chilling-sensitive). While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time (MGT), and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde (MDA) content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase (POD) activity, and catalase (CAT) activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60~64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.     

硝基苯胁迫对农作物的影响

硝基苯是一种剧毒化合物,对农作物产量和品质造成危害,也会严重威胁人类健康．