连续生产精品肝素钠的新工艺

本文首次报道连续生产精品肝素钠的新工艺。猪小肠粘膜的提取液在用离子交换树脂吸附之前,先经过氧化除杂蛋白和脱色过程,既提高了树脂对肝素钠的吸附率,同时也减轻提取液中杂质对树脂的竞争和毒害。肝素钠从树脂上被洗脱后,再连续地进行再氧化、除酸、碱性蛋白和核酸、酒精反复沉淀等工艺过程,生产出精品肝素钠,效价为156±5u/mg,得率为1.092±0.035亿单位/1000kg粘膜,本工艺具有较大的应用价值。     

大尺寸YBa2Cu3O7—δ超导体的研制

利用固相反应法成功地制备了直径为100mm,厚为5mm的大尺寸YBa_2Cu_3O_(7-δ)超导体。在通氧,930℃热处理45min后,超导体的上限转变温度为94K,零电阻温度为92K。x射线衍射进行物相定性,扫描电镜进行形貌和超导电性关系的对比观察。选区电子衍射给出YBa_2Cu_3O_(7-δ)超导体的晶格参数为a=0.348nm,b=0.377nm,c=0.716nm,属于正交晶系。     

Are you growing systems thinking managers? Use a systems model to teach and practice organizational analysis and planning,management policy,and organizational development

This paper discusses the use of the Kast and Rosenzweig systems and contingency model for teaching and practice in organizational analysis and planning, management policy, and organizational development. The need for an organizational model for graduate students and field-based managers and executives is identified. The model is presented beginning with the Kast and Rosenzweig work, with integration of research by Daft, Schein, Trist, Deal and Kennedy, Ackoff, Delbecq, and Mintzberg. The teaching and practice uses of the model in four areas are presented, including organizational analysis and planning, management policy making, and organizational development. In each area case examples of the use of the model in teaching and practice are presented. Needs for future research and implications for the use of the model are discussed.     

Szász-Mirakyan算子对不连续函数的逼近研究

研究用szász-Mirakyan算子S_n(f, x)逼近在(0,+∞)上具有第一类间断点的有界函数了,给出了收敛速度的估计。     

How do Shp2 mutations that oppositely influence its biochemical activity result in syndromes with overlapping symptoms?

Activating and inactivating mutations of SHP-2 are responsible, respectively, for the Noonan (NS) and the LEOPARD (LS) syndromes. Clinically, these developmental disorders overlap greatly, resulting in the apparent paradox of similar diseases caused by mutations that oppositely influence SHP-2 phosphatase activity. While the mechanisms remain unclear, recent functional analysis of SHP-2, along with the identification of other genes involved in NS and in other related syndromes (neurofibromatosis-1, Costello and cardio-facio-cutaneous syndromes), strongly suggest that Ras/MAPK represents the major signaling pathway deregulated by SHP-2 mutants. We discuss the idea that, with the exception of LS mutations that have been shown to exert a dominant negative effect, all disease-causing mutations involved in Ras/MAPK-mediated signaling, including SHP-2, might lead to enhanced MAPK activation. This suggests that a narrow range of MAPK signaling is required for appropriate development. We also discuss the possibility that LS mutations may not simply exhibit dominant negative activity. Received 30 November 2006; received after revision 8 February 2007; accepted 13 March 2007     

哈里·柯林斯思想对SSK的贡献研究

在诸多科学知识社会学的文献中,柯林斯文章的引证率位居同类研究者榜首,文章分析了哈里·柯林斯在其研究范围内做出的贡献。     

The neuronal sortilin-related receptor SORL1 is genetically associated with Alzheimer disease

The recycling of the amyloid precursor protein (APP) from the cell surface via the endocytic pathways plays a key role in the generation of amyloid beta peptide (Abeta) in Alzheimer disease. We report here that inherited variants in the SORL1 neuronal sorting receptor are associated with late-onset Alzheimer disease. These variants, which occur in at least two different clusters of intronic sequences within the SORL1 gene (also known as LR11 or SORLA) may regulate tissue-specific expression of SORL1. We also show that SORL1 directs trafficking of APP into recycling pathways and that when SORL1 is underexpressed, APP is sorted into Abeta-generating compartments. These data suggest that inherited or acquired changes in SORL1 expression or function are mechanistically involved in causing Alzheimer disease.     

解释学习在机器人过程控制中的应用

机器人过程控制是智能机器人系统的一个特别重要而又十分复杂的研究课题。本文将解释学习应用于机器人过程控制，为之开发了一种新的方法。仿真结果表明，该方法可行、有效。同时，还尝试了将Ｐｒｏｌｏｇ语言作为机器人过程控制的运行机制的形式化表达工具的可能性。     

感应加热钢包炉电磁与结构优化

感应加热钢包炉是国外新发展的一种二次精炼及加热设备，具有高效、低能耗、无污染的特点，本文在感应加热钢包炉电磁与结构分析工作的基础上，用电磁场数值模拟方法对感应加热钢包炉的电磁设计和包壳结构进行优化。