Yushu earthquake synergic analysis using multimodal SAR datasets

The large earthquake measuring 7.1 on the Richter scale that occurred in Yushu County, Qinghai Province, China, on April 14, 2010, caused a huge loss of life and major damage to people’s properties. Using three modal synthetic-aperture radar (SAR) datasets, wide-swath SAR, interferometric SAR and polarimetric SAR, the following studies were conducted: (1) From Radarsat-2 wide swath SAR data, the regional geological structures and lithologic distribution characteristics of the Yushu earthquake were analyzed. (2) Using advanced land observing satellite/phased array L-band interferometric SAR data, the coseismic deformation field of the Yushu earthquake was obtained, and the size and spatial distribution of deformation were studied combining with the result of regional geological background analysis. (3) From Radarsat-2 polarimetric SAR data, the H-α-ρ method was used to extract the spatial distribution of building collapse caused by the earthquake in the Yushu urban area, and the reasons for the severe earthquake damage to buildings are also discussed and assessed. The study results demonstrate the effectiveness and important potential of using multimodal SAR data for synergic analysis and assessment of earthquake disasters.     

Characteristics of magnetocardiography and electrocardiography in the time-frequency domain

As the carriers of electromagnetic information about the cardiac system,both magnetocardiography(MCG) and electrocardiography(ECG) are non-stationary signals(NSS).The essential and crucial features of NSS are the local time-frequency characteristics(LTFCH).Under the constraint of the uncertainty principle in the time-frequency domain(TFD),the LTFCH of those non-stationary signals can be determined by evolutionary spectrum analysis(ESA).In this paper,by analyzing the QRS complexes of both MCG and ECG data from healthy volunteers,we have derived some characteristic parameters(CHPs) in the TFD,such as the quality factor(Q) and center frequency(fz).According to the experiment results,we believe that there are threshold ranges of Q and fz values in the dynamic behavior of the cardiac system for healthy projects.If the CHPs are in the proper ranges,the cardiac system is in a normal condition and homeostasis can be self-correcting.In contrast,if the values of the CHPs are less than the proper ranges,the homeostasis of the cardiac system is lost and some cardiac diseases may result.The assumption of the threshold ranges is verified by sample data from different cardiac diseases,and the results support the assumption.The CHPs are not only a kind of new reference criterion for ECG in clinical diagnosis,but also afford a technological route for the application of MCGs in cardiology.     

1eV带隙GaNAs/InGaAs短周期超晶格太阳能电池的设计

使用In,N分离的GaNAs/InGaAs短周期超晶格作为有源区是未来实现高效率GaInNAs基太阳能电池的重要结构之一.同时,考虑到具有1eV带隙的GaInNAs子电池的重要性以及与Ge衬底晶格匹配的优势,基于Ge衬底上的四结及多结太阳能电池无疑荣景可期.为在实验上较好地控制所需带隙,我们利用传输矩阵方法从理论上计算了实现1eV带隙下超晶格的周期数、垒层厚度以及In,N的浓度,并进一步讨论分析1eV带隙下的多个相关参数的对应关系以及超晶格的应变状态.     

氨甲环酸与Wnt信号通路中含kringle结构域蛋白的结合对新生小鼠骨密度的影响

最近研究发现Wnt信号通路在骨形成过程中发挥重要作用Wnt受体如脂蛋白相关蛋白5（lrp5）和孤独受体（Ror2）的缺失或突变导致骨的不正常发育．Dkk是一个分泌型规范Wnt信号系统的抑制剂，通过与脂蛋白相关蛋白5和最近新发现的一种含kringle结构域的蛋白kremen形成三聚体复合物．这种复合物随即被细胞内吞，从而导致细胞表面Wnt受体脂蛋白相关蛋白5水平迅速下降，从而达到抑制Wnt信号通路的日地．通过对kremen和Ror2蛋白序列分析发现kremen和Ror2的胞外部分均含有一个结构上能与赖氨酸结合的kringle结构域．通过给怀孕母鼠注射一种赖氨酸类似物——氨甲环酸来研究kremen和Ror2的kringle结构域上的赖氨酸结合位点被占据对小鼠骨发育的作用．但是，研究结果表明AMCA组和对照组之间的骨密度并没有显著差异，揭示赖氨酸结合位点不参与骨的发育调控．     

A novel strategy for cancer treatment: Targeting cancer stem cells

Cancer stem cell/tumor-initiating cell （CSC/TIC） is a subclass of cancer cells possessing parts of properties of normal stem cell. It has a high capacity of proliferation and plays a pivotal role in tumor recurrence and tumor resistance to radiotherapy and chemotherapy. At present, small molecule inhibitors and fusion proteins are widely used in the CSC-targeting strategy. Gene-virotherapy, which uses oncolytic adenovirus as a vector to mediate the expression of therapeutic gene, shows a significant superiority to other regimens of cancer treatment and has a good efficacy in the treatment of solid tumors. Thus, it is a promising choice to apply gene-virotherapy into the CSC-targeting treatment. Based on the molecular mechanism underlying CSC self-renewal, a series of effective strategies for targeting CSC have been established. This review will summarize the recent research progresses on CSC-targeting treatment.     

尿激酶体外抑制人体免疫缺损病毒的侵染能力

人体免疫缺损病毒的包膜蛋白gp120的V3环区包含一段在人类蛋白质中很少出现的高度保守序列，但这段序列与纤溶酶原被纤溶酶原激活剂酶切位点附近序列有同源性．由于V3环区在人体免疫缺损病毒侵染细胞过程中的重要性，评估了尿激酶对人体免疫缺损病毒侵染能力的影响．通过检测逆转录酶活力，P24抗原的表达和合胞体形成情况发现尿激酶可以抑制人体免疫缺损病毒对多种淋巴瘤和白血病细胞系，如MT4、CCM、H9和外周血单核细胞的侵染能力，并且这种抑制与尿激酶浓度呈剂量依赖关系．那些能够被尿激酶抑制的人体免疫缺损病毒株其V3环区序列必须与纤溶酶原激活区亭列同源，实验事常用病毒株包括BRU和RF以及某些野生病毒株．研究结果显示尿激酶在体外实验中可以抑制人体免疫缺损病毒的侵染能力．