正算子方块积的代数性质

通过量子计算和量子信息理论中两个物理量concurrence和fidelity引入正算子方块积的概念,类比序列积代数性质的相关结果,给出了方块积的一些代数性质和反例,并对不同Hilbert空间之间保持concurrence或fidelity的变换进行了刻画．     

“经济数学”课程教学模式改革实践与分析评估 3

以促进学生的全面发展和潜能开发为目标的"经济数学"课程教学模式改革,在"三个一工程"实践中,分别实施了分层教学、学生任选教师教学、分层+任选教师的教学模式;通过对不同教学模式的实践及效果评价,分析总结了不同教学模式在人才培养中的作用与意义,提出了提高教学质量的教学模式及其改进措施.     

基于计算机三维建模的“工程制图”课程测绘实践研究 3

分析了计算机三维建模运用于制图测绘环节的必要性,以锻炼学生的实践能力、设计思维及团队精神为目的,提出了运用项目教学法引领测绘训练的全过程,并将计算机三维建模作为测绘训练的主线;实践表明,该教学方法的改革不仅使得课程设计质量较好,学生对机械设计专业的认识也有了较大的提高.     

有序介孔氧化硅材料中的药物分子 组装及缓释研究进展

伴随经济全球化和知识经济的到来,传统的刚性管理模式严重制约着企业人力资源的创新性和主动性,企业人力资源只有实施柔性管理才能适应当今的竞争环境。介绍了人力资源柔性管理的定义、国内外学者在这一领域的研究状况及启示。国内外的柔性管理研究成果丰富,具有一定的广度和深度,但还存在不足。未来研究不仅要进行定性研究,更要进行定量分析;不仅要发展和丰富理论知识,更要将这些理论应用到实际发生的人力资源柔性管理的案例中,对其进行详细描述、解释,以找出可以用来指导企业实践的规律性东西,建立起科学的理论体系,从而进一步丰富和发展企业中的人力资源柔性管理理论。     

“装箱问题的一种新的近似算法”的一个注记

一维装箱问题(Bin-Packing)是一个著名的NP难的组合问题,具有极其广泛的应用背景,受到了深入细致的研究,取得了许多好的成果.2004年孙春玲等1对一维装箱问题给出一个新的近似算法,称作交叉算法,证明该算法达到一维装箱问题的最好的近似值3/2.       

《云南大学学报(自然科学版)》编委风采

李永昆,男,博士。云南大学数学与统计学院教授、副院长、博士生导师、中国数学会理事、云南省数学会副理事长。2002年11月被云南省人民政府授予云南省中青年学术和技术带头人称号。先后主持完成过国家自然科学基金2项,云南省自然科学基金4项。2004年获“宝钢优秀教师奖”。2005年获云南省自然科学二等奖。已发表学术论文110余篇,其中40余篇被SCl收录,并被SCI引用350余次。       

细推物理须行乐——记世界物理年4位中科院院士到云南大学讲学访问

为纪念世界物理年,受云南大学邀请,2005年3月21日～30日,中国科学院郝柏林、孙义燧、李家明、葛墨林4位院士对云南大学进行了访问.21日4位院士先与云南大学非线性复杂系统中心的师生们进行了座谈,随后郝柏林院士和李家明院士在云南大学科学馆分别做了“Finding Genesin the Rice Genome”和“基础研究的乐趣”两场报告.郝柏林院士还于29日下午做了“数字文明:物理学和计算机”的报告.院士们的报告精彩生动,引人入胜,不时赢得台下热烈的掌声.报告结束后大家争相提问,院士们耐心细致地分别作了回答.郝柏林院士和李家明院士等大师们渊博的知识严谨的治学作风,谦虚的品格给在场的老师和同学们留下了深刻的印象.       

Targeted inhibition of Livin resensitizes renal cancer cells towards apoptosis

Cancer cells are typically characterized by apoptosis deficiency. In order to investigate a possible role for the anti-apoptotic livin gene in renal cell cancer (RCC), we analyzed its expression in tumor tissue samples and in RCC-derived cell lines. In addition, we studied the contribution of livin to the apoptotic resistance of RCC cells by RNA interference (RNAi). Livin gene expression was detected in a significant portion of RCC tumor tissue specimens (13/14, 92.9%) and tumor-derived cell lines (12/15, 80.0%). Moreover, targeted inhibition of livin by RNAi markedly sensitized RCC cells towards proapoptotic stimuli, such as UV irradiation or the chemotherapeutic drugs etoposide, 5-fluorouracil, and vinblastine. These effects were specific for livin expressing tumor cells. We conclude that livin can contribute significantly to the apoptosis resistance of RCC cells. Targeted inhibition of livin could represent a novel therapeutic strategy to increase the sensitivity of renal cancers towards pro-apoptotic agents. Received 30 November 2006; received after revision 22 February 2007; accepted 20 March 2007     

Starch-binding domains in the post-genome era

Starch belongs to the most abundant biopolymers on Earth. As a source of energy, starch is degraded by a large number of various amylolytic enzymes. However, only about 10% of them are capable of binding and degrading raw starch. These enzymes usually possess a distinct sequence-structural module, the so-called starchbinding domain (SBD). In general, all carbohydrate-binding modules (CBMs) have been classified into the CBM families. In this sequence-based classification the individual types of SBDs have been placed into seven CBM families: CBM20, CBM21, CBM25, CBM26, CBM34, CBM41 and CBM45. The family CBM20, known also as a classical C-terminal SBD of microbial amylases, is the most thoroughly studied. The three-dimensional structures have already been determined by X-ray crystallography or nuclear magnetic resonance for SBDs from five CBM families (20, 25, 26, 34 and 41), and the structure of the CBM21 has been modelled. Despite differences among the amino acid sequences, the fold of a distorted β-barrel seems to be conserved together with a similar way of substrate binding (mainly stacking interactions between aromatic residues and glucose rings). SBDs have recently been discovered in many non-amylolytic proteins. These may, for example, have regulatory functions in starch metabolism in plants or glycogen metabolism in mammals. SBDs have also found practical uses. Received 25 May 2006; received after revision 26 June 2006; accepted 3 August 2006     

吸收对对称性一维三元光子晶体能带的影响

利用复折射率及传输矩阵理论,研究了光子晶体的吸收对对称性一维三元光子晶体能带及透射峰的影响,研究表明:在反射波中,禁带的反射率随消光系数的增加而迅速降低,当k增加到0.005时,禁带边缘模糊,不存在明显的禁带;在透射波中,随着消光系数的增大,禁带边缘逐渐模糊,当k增加为0.003时,透射率降为0.35;光子晶体的消光系数对禁带内透射峰的透射率有着明显的影响,当k为0.001时,透射率下降到0.15,随着消光系数的增加,透射峰的半峰全宽随之增加,但对透射峰的中心波长没有影响.