多维动态信用评估的信用状态空间结构研究

从理论上讨论了多维动态信用评估（MDCE）的状态空间结构，提出信用状态维度、信用状态空间（CSS）、ε-等信用状态和ε-伪等信用状态等概念.在构造信用状态空间的基础上，结合空间分析方法和优化技术，构建了偏序结构下的多目标评估模型，所有待评估的信用主体被描述为信用状态空间中点的集合，并归入相应的信用状态等级，最后给出一个应用示例.     

基于会计利润与经济利润的绩效指标的一致性

从排序和线性关系两方面考察了2001年化工行业36家上市公司的绩效数据。结果表明:净资产收益率、经济增加值和基于因子分析的综合财务绩效排序两两正相关,且均与市场增加值排序没有关联。基于因子分析的综合财务绩效与净资产收益率,经济增加值与净资产收益率、市场增加值存在显著的线性关系;没有发现基于因子分析的综合财务绩效与经济增加值、市场增加值,市场增加值与净资产收益率存在线性关系的明显证据。     

论中国古代文学中的"悲秋"意识

“悲秋”是中国古代文学中一个源远流长的主题。“睹落叶而悲伤,感秋风而凄怆”,这一“悲秋”文学主题从《诗经》、《楚辞》到“建安文学”,从唐诗宋词到元曲清诗,历经上千年的发展、嬗变和积淀,从无意识到有意识,最终形成特具中国传统文化内涵的“悲秋”文学意识。“悲秋”文学意识的形成与中国传统文化有着深刻的精神联系,同时也可窥见中国传统士人悲剧性命运之一斑。     

A RING-type ubiquitin ligase family member required to repress follicular helper T cells and autoimmunity

Despite the sequencing of the human and mouse genomes, few genetic mechanisms for protecting against autoimmune disease are currently known. Here we systematically screen the mouse genome for autoimmune regulators to isolate a mouse strain, sanroque, with severe autoimmune disease resulting from a single recessive defect in a previously unknown mechanism for repressing antibody responses to self. The sanroque mutation acts within mature T cells to cause formation of excessive numbers of follicular helper T cells and germinal centres. The mutation disrupts a repressor of ICOS, an essential co-stimulatory receptor for follicular T cells, and results in excessive production of the cytokine interleukin-21. sanroque mice fail to repress diabetes-causing T cells, and develop high titres of autoantibodies and a pattern of pathology consistent with lupus. The causative mutation is in a gene of previously unknown function, roquin (Rc3h1), which encodes a highly conserved member of the RING-type ubiquitin ligase protein family. The Roquin protein is distinguished by the presence of a CCCH zinc-finger found in RNA-binding proteins, and localization to cytosolic RNA granules implicated in regulating messenger RNA translation and stability.     

Development of Th1-type immune responses requires the type I cytokine receptor TCCR

On antigen challenge, T-helper cells differentiate into two functionally distinct subsets, Th1 and Th2, characterized by the different effector cytokines that they secrete. Th1 cells produce interleukin (IL)-2, interferon-gamma (IFN-gamma) and lymphotoxin-beta, which mediate pro-inflammatory functions critical for the development of cell-mediated immune responses, whereas Th2 cells secrete cytokines such as IL-4, IL-5 and IL-10 that enhance humoral immunity. This process of T-helper cell differentiation is tightly regulated by cytokines. Here we report a new member of the type I cytokine receptor family, designated T-cell cytokine receptor (TCCR). When challenged in vivo with protein antigen, TCCR-deficient mice had impaired Th1 response as measured by IFN-gamma production. TCCR-deficient mice also had increased susceptibility to infection with an intracellular pathogen, Listeria monocytogenes. In addition, levels of antigen-specific immunoglobulin-gamma2a, which are dependent on Th1 cells, were markedly reduced in these mice. Our results demonstrate the existence of a new cytokine receptor involved in regulating the adaptive immune response and critical to the generation of a Th1 response.     

Annual modulation of triggered seismicity following the 1992 Landers earthquake in California

The mechanism responsible for the triggering of earthquakes remains one of the least-understood aspects of the earthquake process. The magnitude-7.3 Landers, California earthquake of 28 June 1992 was followed for several weeks by triggered seismic activity over a large area, encompassing much of the western United States. Here we show that this triggered seismicity marked the beginning of a five-year trend, consisting of an elevated microearthquake rate that was modulated by an annual cycle, decaying with time. The annual cycle is mainly associated with several hydrothermal or volcanic regions where short-term triggering was also observed. These data indicate that the Landers earthquake produced long-term physical changes in these areas, and that an environmental source of stress--plausibly barometric pressure--might be responsible for the annual variation.     

Distinct types of diffuse large B-cell lymphoma identified by gene expression profiling

Diffuse large B-cell lymphoma (DLBCL), the most common subtype of non-Hodgkin's lymphoma, is clinically heterogeneous: 40% of patients respond well to current therapy and have prolonged survival, whereas the remainder succumb to the disease. We proposed that this variability in natural history reflects unrecognized molecular heterogeneity in the tumours. Using DNA microarrays, we have conducted a systematic characterization of gene expression in B-cell malignancies. Here we show that there is diversity in gene expression among the tumours of DLBCL patients, apparently reflecting the variation in tumour proliferation rate, host response and differentiation state of the tumour. We identified two molecularly distinct forms of DLBCL which had gene expression patterns indicative of different stages of B-cell differentiation. One type expressed genes characteristic of germinal centre B cells ('germinal centre B-like DLBCL'); the second type expressed genes normally induced during in vitro activation of peripheral blood B cells ('activated B-like DLBCL'). Patients with germinal centre B-like DLBCL had a significantly better overall survival than those with activated B-like DLBCL. The molecular classification of tumours on the basis of gene expression can thus identify previously undetected and clinically significant subtypes of cancer.     

基于Simulink的子导弹全弹道仿真

在MATLAB／Simulink环境下，针对子导弹武器系统，应用全弹道建模方法开发了包括运动学与动力学模块、制导与控制系统模块，弹目相对运动模块等组成的仿真系统数学模型，进行了全弹道数字仿真。仿真实验表明，该仿真系统较好的模拟了子导弹的飞行弹道，为子导弹武器系统的开发研制提供了必要的仿真工具。     

鸡与鹌鹑杂交种早期胚胎发育特异表达基因的初步筛选

利用mRNA差异显示技术，对入孵67～91h的鸡（♀）与鹌鹑（♂）杂交种胚胎中mRNA差异表达进行比较，筛选出与杂交种胚胎早期发育相关的特异表达基因，并克隆测序这些序列，分析这些基因在杂交受精蛋早期胚胎发育中的作用，及其对杂交种早期胚胎死亡是否有影响。分析结果表明，已经获得6个杂交种孵化不同时期的基因片段与鸡的mRNA序列具有高度同源性。其中，孵化第72h时胚胎mRNA表达的序列与鸡雌激素受体结合位点相关抗原mRNA具有高度同源性，孵化第79h时产生的差异片段经过比对，发现：与鸡（♀）肽酰-脯氨酰异构酶类似的mRNA序列具有高度同源性。而杂交种胚胎发育到第72h时，可检测到鸡雌激素受体结合位点相关抗原mRNA的表达，比前人所得到的表达时间（胚胎发育在第84h时检测到）提前了12h，这很可能是造成杂交种早期胚胎大量死亡的原因之一。