Tobacco floral homeotic gene homologues: partial sequence and expression pattern

Using PCR approach, three cDNA sequences, NTSQUA4, NTSQUA12 and NTSQUA15, were amplified from first_strand cDNAs of wild tobacco flower buds and identified as homologues for floral homeotic genes. All the three clones contained domains that a floral homeotic gene generally had, i.e. I domain, K domain and C_terminal domain except MADS_ box since the PCR primers were designed beyond this region. In addition, the amino acid sequences of them showed 50%-60% identity (70%-80% similarity) with the known floral organ identity class A gene AP1 and SQUA, possibly indicating that they are class A_like genes. NTSQUA4 and NTSQUA412 shared 95% identity in their amino acid sequence, while NTSQUA415 exhibited only 47% identity as compared with NTSQUA4 and NTSQUA12. Within tobacco flower, NTSQUA4 was expressed in sepals, petals and carpels, but not in stamens, while NTSQUA15 was expressed in every whorl of the flower. The possible functions of these genes are discussed.     

论教师在化学教学中的教育主导作用

“教为主导,学为主体”不仅是现代教学论的核心思想,面且也是教育哲学的基本理论问题。欲要全面正确理解它的本质涵义及其内在关系,首先须在思想方法论上转变。本文从理论上阐述了教学过程,实际是个可控的具有育人成才功能的信息流通系统。“教为主导”“学为主体”都是辩证的。教师和学生都具有主客体的二重性和同一性。机械地搬用两极模式的二分法,把教与学作为“一对矛盾”来考察,必然导致理论上的混乱和思想上的僵化。     

Geographical history的概念和汉译——兼论Alan R.H.Baker地理历史学思想

针对国内将贝克的geographical history一词译为＂地理学史＂或＂地理史＂的问题,结合他的新作对geographical history这一术语的论述及学科合法地位的诉求,认为应译为＂地理历史学＂。同时结合国内学者对＂地理历史学＂的术语混乱和学科诉求做了论述,分析了＂地理历史学＂术语混乱的部分原因。认为对国内外＂地理历史学＂思想应给予注意,给予＂地理历史学＂一个合法的学科地位。     

Demir-Marsh不等式的推广及其稳定性

利用代数不等式将Demir-Marsh不等式推广到高维空间,并给出它的稳定性.     

孪生组合恒等式（十四）——幂级数类型

通过两类孪生幂级数,应用Fibonacci数和Lucas数的性质,获得8组孪生组合恒等式.     

炫耀性消费的主观意义

人们进行炫耀性消费,不仅仅是为了显示自己的身份和地位,同时也是为了获得身份和地位。不同的消费者具有不同的炫耀性消费特征,身份危机感越强的消费者炫耀性消费倾向越明显。而女性由于身份危机的因素,显示出更强的炫耀性消费特征。     

从自我同一性的视角评析大学校园中的偏差行为

自我同一性的确立是青年期社会化的主要课题，青少年在完成自我同一过程中的种种尝试、选择和体验，会给他们带来较多的偏差行为。阐述并运用自我同一性理论，评析大学校园中偏差行为的心理成因，为寻求有效的学生管理策略以及学生心理发展辅导提供切实的心理学依据。     

OWDP and its secure implementation

Here we present one design based on OWDP for secure high-speed IP network performance monitor system. Based on the analysis of OWDP protocol and the high-speed IP network performance's real-time monitor infrastructure, the paper illustrates the potential security problems in OWDP and its possible weakness when applied in the monitor infrastructure. One secure improvement design based on Otway-Rees authentication protocol is put forward, which can improve the security of the implementation of OWDP and the monitor architecture. Having kept OWDP's simplicity and efficiency, the design satisfies the real-time demand of high-speed network performance monitor and will effectively safeguard the monitor procedure against intensive attacks. Foundation item: Supported by the 863 National High-Tech Project (863-300-02-09-99) and Key Research Project of Hubei Province (991P110) Biography: Xu Ning (1975-), male, Master candidate, research interest: distributed system, computer security.     

关于平均的一些恒等式Ⅱ

本文是 [7]的续文。旨在把 [3]与 [7]中所证明含有恒等平均、几何平均和对数平均的恒等式推广到一般情形。借助于此 ,导出更一般化的相关不等式     

多项式恒等定理的应用

多项式恒等定理在多项式理论中占有重要地位,该文介绍了它在中学代数和三角中的应用。