浅谈中国现代文学批评史上古典主义倾向的产生发展和演变

在中国现代文学批评史上,一直存在着古典主义的批评倾向。并且从各种不同流派观点中呈现出各种各样的面目,但是其总的倾向还是一致的,这种一致性就形成了中国现代文学的古典主义倾向。     

基于意群的计算机证据倾向性研究

计算机证据具有数量繁多、复杂多样等特点,因此如何快速地定位可疑文件是目前亟需解决的问题。利用意群概念和朴素贝叶斯算法对计算机证据的倾向性进行了分析研究。通过训练产生以意群为单位存储的倾向性词库。利用朴素贝叶斯算法,对待测文档中筛选出的一定数目的关键词的概率进行计算,从而得出待测文档内容的倾向性。实验表明基于意群的计算机证据倾向性研究方法在获取可疑文件方面有很好的应用效果。     

Mammalian phylogeny: shaking the tree.

Recent palaeontological discoveries and the correspondence between molecular and morphological results provide fresh insight on the deep structure of mammalian phylogeny. This new wave of research, however, has yet to resolve some important issues.     

Relative helix-forming tendencies of nonpolar amino acids

An important issue in understanding the relationship between protein sequence and structure is the degree to which different amino acids favour the formation of particular types of secondary structure. Estimates of the 'helix-forming tendency' of amino acids have been made based on 'host-guest' experiments, in which copolymers are made of the amino acid of interest (the 'guest') and a host residue (typically hydroxypropyl- or hydroxybutyl-L-glutamine). Recently, however, short alanine-based peptides were found to form stable monomeric helices in water, contrary to the result predicted from host-guest experiments. We have now measured the helix-forming tendency of five different nonpolar amino acids (Ala, Ile, Leu, Phe, Val) by substituting each in turn for alanine in a 17-residue alanine-based peptide and determining the extent of alpha-helix formation. Our results differ from those of host-guest experiments both in the degree of variation in helix-forming tendency of different amino acids, and in the rank order of the helix-forming tendency. We conclude that the helix-forming tendency of a particular amino acid depends on the sequence context in which it occurs; and the restriction of side-chain rotamer conformations is important in determining the helix-forming tendency.     

Hydatellaceae are water lilies with gymnospermous tendencies

The flowering plant family Hydatellaceae was recently discovered to be allied to the ancient angiosperm lineage Nymphaeales (water lilies). Because of its critical phylogenetic position, members of the Hydatellaceae have the potential to provide insights into the origin and early diversification of angiosperms. Here I report that Hydatella expresses several rare embryological features that, in combination, are found only in members of the Nymphaeales. At maturity, the female gametophyte is four-celled, four-nucleate and will produce a diploid endosperm, as is characteristic of most early divergent angiosperm lineages. As with all members of the Nymphaeales, endosperm in Hydatella is minimally developed and perisperm is the major embryo-nourishing tissue within the seed. Remarkably, Hydatella exhibits a maternal seed-provisioning strategy that is unique among flowering plants, but common to all gymnosperms: pre-fertilization allocation of nutrients to the embryo-nourishing tissue. This exceptional case of pre-fertilization maternal provisioning of a seed in Hydatella may well be an apomorphic feature of Hydatellaceae alone but, given the newly discovered phylogenetic position of this family, potentially represents a plesiomorphic and transitional condition associated with the origin of flowering plants from gymnospermous ancestors.     

不良地质现象对城市环境的影响及其防治

针对城市地下工程活动引起的不良地质现象 :地面沉降、地面塌陷、斜坡破坏、地下水的不良作用和地下水的污染等因素对城市环境的影响 ,提出其防治措施     

住宅发展的必然趋势之一--智能住宅

文章介绍了智能小区的起源、发展.具体阐述了智能小区所包含的功能及小区智能化开发中的几个关键问题,论述了现今国内小区智能化的实际情况及发展必然趋势.提出在规划、设计时要考虑技术发展这一因素,一定做到超前,即在技术(系统)方面超前、在预留接口(模块)方面超前、在敷设管线方面超前.     

哺乳动物精子发生及其基因表达调控

精子发生的过程是一个受机体严密调节的过程,其中包括激素调节、睾丸旁分泌因子的调节和其它信号分子的调节,睾丸特异性表达的基因在这一调节过程中发挥着重要的作用。研究睾丸特异性表达基因的功能的最终目的是阐述精子发生的机理和发现新一代高效、特异、可逆的男性避孕药物的靶蛋白基因。     

Mammalian MAP kinase signalling cascades

Mitogen-activated protein kinases (MAPKs) are important signal transducing enzymes, unique to eukaryotes, that are involved in many facets of cellular regulation. Initial research concentrated on defining the components and organization of MAPK signalling cascades, but recent studies have begun to shed light on the physiological functions of these cascades in the control of gene expression, cell proliferation and programmed cell death.     

不同自燃性煤氧化阶段的表征差异

对3种不同自燃倾向性煤样进行低温氧化实验,利用CO体积分数与煤体温度间变化的计算模型,求解出活化能和煤氧化过程发生转变的特征温度,同时结合热重-差示扫描量热(TGDSC,theremogravimetric analysis-differential scanning calorimetry)实验结果,分析了不同自燃性煤氧化特性和活化能的低温表征规律。结果表明:1)低温氧化阶段,CO生成量、耗氧量和耗氧速率随着煤自燃倾向性增强而增大;不同煤样在实验过程中出现同样的CO生成量和耗氧速率急剧上升的温度拐点,且煤的自燃性越强,该拐点温度越低,同时CO体积分数的变化具有明显的阶段性。2)不同自燃性煤氧化阶段活化能变化规律存在显著差异,当各煤样的温度到达活性温度时,活化能快速减少,且活化能变化点对应于煤氧化过程发生转变的特征温度点。3)根据煤特征温度和活化能的变化规律,把煤低温氧化进程分为4个阶段,分别为表面氧化、氧化自热、加速氧化和深度氧化。