支持数字签名的TLS改进协议

为弥补TLS (transport layer security)协议在"抗抵赖"安全特性上的缺陷,提出了一种对TLS协议的改进方案.在保持TLS协议原有安全性的前提下对TLS协议中最主要的两个子协议--握手协议和记录协议分别进行了扩展与改进,在其内部引入了数字签名及验证机制,并且支持在握手协议中对数字签名及验证功能进行动态协商,同时与原有的TLS协议兼容.实验表明,改进后的TLS协议性能优良,运算速度有约10%的提升.     

Molecular genetic basis for the rhino mouse from Chinese KM subcolony

Both the rhino mouse and hairless mouse resulted from hairless gene mutation, but they show different phenotypes of skin physiology. The rhino mouse has more similar histological characters to human papular alopecia.Therefore rhino mouse is a good experimental animal model for human papular alopecia. This study reports a hairless mouse named rhino KIZ, arose from KM colony in Kunming Institue of Zoology, by systematic studies on morphology,skin histopathology, gene sequence, pedigree and protein domain analysis. The results demonstrate that a C-to-T transition in exon 11 of hr gene (The mutant gene has been applied for a Chinese patent (patent No. 03135280)) results in the rhino KIZ. The rhino KIZ with clear genetic mechanism will be a useful animal model.     

企业规划与信息系统规划集成影响实证研究

网络战略信息系统时期,信息系统规划(ISP)与企业规划(BP)关系研究成为企业信息化建设的焦点问题．文章提出了BP—ISP集成阶段及其对规划活动影响的概念模型,并运用中国企业的经验数据,利用结构方程模型对集成程度与业务规划活动、ISP的地位及ISP实现过程中出现的问题等进行了实证分析．研究表明,随着集成阶段升高,规划活动中出现问题的程度呈现逐渐减弱的趋势,而企业规划、企业对ISP的战略需求以及首席信息官(CIO)的作用都变得更加重要．     

How retinoids regulate breast cancer cell proliferation and apoptosis

Breast cancer still remains a major problem in its incidence, morbidity and mortality; therefore, more effective strategies for its prevention are urgently needed. Retinoids, natural and synthetic derivatives of vitamin A, possess antiproliferative and proapoptotic properties, making them a promising class of chemopreventive agents against breast cancer. The efficacy of all-trans retinoic acid, 9-cis-retinoic acid, LGD1069 (Targretin, bexarotene), and N-(4-hydroxyphenyl)retinamide (fenretinide) as breast cancer chemopreventive agents is being studied. A better understanding of the molecular mechanisms of action of these agents should lead to improvements in their clinical application. In this review, we discuss the mechanisms by which retinoids exert their antiproliferative and apoptotic effects in breast cancer cells.Received 5 January 2004; received after revision 9 February 2004; accepted 12 February 2004     

Distribution of HIV-1 in the genomes of AIDS patients

The localization of HIV-1 proviruses in compositional DNA fractions from 27 AIDS patients during the chronic phase of the disease with depletion of CD4+ and different levels of viremia showed the following. (1) At low viremia, proviruses are predominantly localized in the GC-richest isochores, which are characterized by an open chromatin structure; this result mimics findings on HIV-1 integration in early infected cells in culture. (2) At higher viremia, an increased distribution of proviruses in GC-poor isochores (which match the GC poorness of HIV-1) was found; this suggests a selection of cells in which the isopycnic localization leads to a higher expression of proviruses and, in turn, to higher viremia. (3) At the highest viremia, integrations in GC-rich isochores are often predominant again, but generally not at the same level as in (1); this may be the consequence of new integrations from the extremely abundant RNA copies.Received 21 November 2003; received after revision 13 January 2004: accepted 15 January 2004     

Description of mechanism function about dehydration of cobalt oxalate dihydrate by multiple rates isotemperature method

0　IntroductionThetechnologyofthermalanalysishasbeenwidelyusedinthestudyofthermalbehaviorandthermalcharacterofsolidstatereaction ,theprimaryintentionofthermalanalysiskineticsistoestablishseparatevaluesofapparentactivationenergyE ,themostprobablemechanism g(α)andthepre exponentialfactorA ,meanwhilethedeterminationofg(α)hasgraduallybeenthefocusofthisfield .Inthisfield ,therearemostlygeneralkineticsmethodsused presently ,suchasCoats Redfern’s[1 ] integralmethod ,Achar’s[2 \〗differentialmet…     

绵羊卵母细胞不同采集方法对体外成熟培养的影响

为提高绵羊卵巢卵母细胞的采集效率,提供用于卵母细胞体外成熟培养和体外受精的更多优质的成熟卵母细胞,试验利用抽吸法和剖切法2种采集方法采集绵羊卵巢卵母细胞进行体外成熟培养并对其效果进行了对比研究.结果表明剖切法获得的卵子数量显著高于抽吸法(P<0.05),而所用时间则无显著差异(P>0.05);A、B级卵母细胞的比例在剖切法中显著高于抽吸法(P<0.05),抽吸法所采集的C级细胞显著高于剖切法(P<0.05);剖切法中卵丘扩散率和第一极体排出率要显著高于抽吸法(P<0.05).     

“三环制“供热系统中热水一级网运行计算研究

针对"三环制"供热系统,建立了热水一级网("二环")运行调节曲线数学模型,从而实现"三环制"供热系统连锁调节和自动控制,达到最大限度的节能.     

生产低硫低烯烃汽油的RIDOS技术

With the application of new techniques, materials and technologies in West-East Gas Transportation Pipeline (WEGTP) project, the design concept of domestic pipeline industrial construction has been updated, speeding up the development and improvement of the strength as a whole in aspects of smelting industry, pipe fabrication, pipeline construction and equipment manufacture, making China‘s pipeline industry catch up with the trend of development of the world advanced level.     

含季节性虚拟变量的GM(1,1)模型及其应用

针对GM（1，1）模型难以准确预测季节性时间序列的问题，本文将季节性虚拟变量作为灰作用量引入传统GM（1，1）模型中，提出了含季节性虚拟变量的GM（1，1）模型（简记为GMSD（1，1））.在GMSD（1，1）模型定义型和白化型的基础上，推导了GMSD（1，1，x⁽¹⁾）模型、GMSD（1，1，x⁽⁰⁾）模型、GMSD（1，1，b）模型、GMSD（1，1，exp）模型、GMSD（1，1，C）模型等五种派生型GMSD（1，1）模型，构建了季节性虚拟变量GM（1，1）模型群.同时利用粒子群算法对GMSD（1，1）模型和GMSD（1，1，exp）模型中的解析式进行最优化求解.最后以中国水力发电量的季度数据为例，验证了含季节性虚拟变量的GM（1，1）模型及其派生模型的有效性和优越性.结果表明：相较于传统GM（1，1）模型，引入季节性虚拟变量的GMSD（1，1）模型及其派生模型更能准确地描述系统特征序列的季节性波动和周期性变化特征.