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101.
张位全 《宝鸡文理学院学报(自然科学版)》2013,33(2):21-25
目的解决贸易谈判中的价格评估,寻找双方都能接受的价格区间。方法根据实际问题,建立一个商业谈判中双向模糊综合评判模型,并运用这个模型解决了服装谈判中买卖双方初步讨价还价的双向模糊综合评判问题。结果建立起了谈判模型,并利用模型分析了服装谈判。结论这个模型是可行的,并符合双方预期。 相似文献
102.
单片机总线上多时钟域下数据传递的可靠性研究 总被引:1,自引:0,他引:1
对单片机总线上多时钟域下数据传递的可靠性进行研究,阐述了使用寄存器锁存电路、多级锁存电路2种方法解决多时钟域下数据传递可靠性时存在的问题,提出了采用4级锁存并判断跳变沿的方式能确保多时钟域下数据可靠传递的方法,具有很高的应用价值. 相似文献
103.
隐式时间步进算法在求解二维物体的散射时,随着时间的推移,也会出现后时不稳定性的问题.文章在先五步后三步平均公式的基础上利用误差公式对系数进行筛选,改善了原公式在隐式时间步进算法中计算二维物体时产生的后时震荡情况;采用基于时域电场积分方程的隐式时间步进算法,分别计算了TM高斯脉冲入射到无限长导体圆柱和导体方柱时的导体表面... 相似文献
104.
Flavin-containing monooxygenase (FMO), like cytochrome P450 (CYP), is a monooxygenase that uses the reducing equivalents of NADPH to reduce one atom of molecular oxygen to water, while the other atom is used to oxidize the substrate. Recently, it was shown that some CYP isoforms have been subject to positive selection. However, it is unknown whether the highly conserved phase I detoxification enzyme, FMO, has undergone similar positive Darwinian selection. We used maximum-likelihood models of codon substitution, evolutionary fingerprinting, and cross species comparison to investigate the occurrence of adaptive evolution in FMO sequences. We used recent genomic data from a range of species, including vertebrates and invertebrates. We present the evidence for the occurrence of adaptive evolution in mammalian FMO 3, 4, 5, and fugu FMOs but not in mammalian FMO 1, FMO 2, frog FMOs, other fish FMOs and invertebrate FMOs. The sites under adaptive evolution were significantly associated with the insertion domain in mammalian FMO 5. We identified specific amino acid sites in FMOs 3–5 that are likely targets for selection based on the patterns of parallel amino acid change. The most likely role of adaptive evolution is the repair of mutations that permitted optimal NADP+ binding and improved catalytic efficiency. The occurrence of positive selection during the evolution of phase I detoxification enzymes such as FMOs 3–5 and fugu FMO suggests the occurrence of both high selection pressure acting on species within their unique habitats and significant changes in intensity and direction (forms of xenobiotics and drugs) resulting from changes in microhabitat and food. 相似文献
105.
Kristin T. Jacobsen Kerstin Iverfeldt 《Cellular and molecular life sciences : CMLS》2009,66(14):2299-2318
The Alzheimer’s amyloid precursor protein (APP) belongs to a conserved gene family that also includes the mammalian APLP1
and APLP2, the Drosophila APPL, and the C. elegans APL-1. The biological function of APP is still not fully clear. However, it is known that the APP family proteins have redundant
and partly overlapping functions, which demonstrates the importance of studying all APP family members to gain a more complete
picture. When APP was first cloned, it was speculated that it could function as a receptor. This theory has been further substantiated
by studies showing that APP and its homologues bind both extracellular ligands and intracellular adaptor proteins. The APP
family proteins undergo regulated intramembrane proteolysis (RIP), generating secreted and cytoplasmic fragments that have
been ascribed different functions. In this review, we will discuss the APP family with focus on biological functions, binding
partners, and regulated processing. 相似文献
106.
讨论了交换主理想整环上交错矩阵的算术距离与距离之间的关系,并用两个矩阵之间的算术距离得到了交换主理想整环上交错矩阵极大集的结构. 相似文献
107.
The infinite domain potential problems arise in many branches of scientific and engineering fields, which by now still pose a great challenge to scientific computing community.This study proposes a novel meshless singular boundary method (SBM) to solve infinite domain potential problems.The SBM is mathematically simple, easy-to-program, meshless and integration-free.To guar-antee the uniqueness of numerical solutions, this article adds a constant term into the SBM approximate representation.The effi-ciency ... 相似文献
108.
线粒体在真核细胞中扮演着重要的角色,其功能障碍与许多疾病的发生密切相关.在这项研究中,我们鉴定了一个有Tim44样结构域(Tim44-like domain)的人类线粒体蛋白编码基因C2ORF47(chromosome 2openreading frame 47).该基因是从人的睾丸组织中克隆出来的,在人体各种组织中广泛表达.序列比对和进化分析表明,该蛋白质和其同系物在脊椎动物中是保守的.采用免疫荧光技术,我们发现该基因产物定位于线粒体.过表达C2ORF47可以抑制细胞增殖.使用siRNA敲减内源的C2ORF47能促进细胞增殖.此外,敲减C2ORF47会导致糖和血清饥饿引发的细胞凋亡大幅减少.总之,在细胞增殖和由饥饿引发的细胞凋亡的调控中,该基因可能发挥重要作用. 相似文献
109.
In this paper,domain decomposition method(DDM) for numerical solutions of mathematical physics equations is improved into dynamic domain decomposition method(DDDM) . The main feature of the DDDM is that the number,shape and volume of the sub-domains are all flexibly changeable during the iterations,so it suits well to be implemented on a reconfigurable parallel computing system. Convergence analysis of the DDDM is given,while an application approach to a weak nonlinear elliptic boundary value problem and a ... 相似文献
110.
刘媛 《重庆三峡学院学报》2012,28(2):132-135
无偿性是知识产权法上公共领域的基本特性,对于保持公共领域的开放性、守护民主自由是必要的,同时也是人们的共识。目前,有学者提出公共领域的有偿制度。从经济学和审美心理学分析,有偿性增加创作成本,不能提高当代创作者竞争力,其国家管理基金的模式也因有损市民社会、对象无法把握、效率低等而不具有正当性和操作性。 相似文献