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171.
商誉问题一直是会计学领域中较为引人关注的一个问题,由于其特殊性许多会计学者从不同的方面进行研究、讨论和分析。本文尝试从正、负商誉比较的角度对商誉问题加以探讨,阐述笔者的若干观点,以期对商誉问题有进一步的正确认识。 相似文献
172.
简要介绍了微处理器的分类及其应用领域,并对我国系列芯片的最新研制和开发情况进行了系统的总结和概括,包括“爱国者”系列芯片、“万通”系列芯片、“同心”DSP芯片以及最高频率CPU芯片等。 相似文献
173.
174.
从哲学内涵上探讨了软动力学的方法论意义 ,并对软动力学理论模型及其核心概念中的辩证思维特征作了延伸性分析 相似文献
175.
The penetrance of dominant erythropoietic protoporphyria is modulated by expression of wildtype FECH. 总被引:8,自引:0,他引:8
Laurent Gouya Herve Puy Anne-Marie Robreau Monique Bourgeois Jer?me Lamoril Vasco Da Silva Bernard Grandchamp Jean-Charles Deybach 《Nature genetics》2002,30(1):27-28
Erythropoietic protoporphyria (EPP) is an inherited disorder of heme biosynthesis caused by a partial deficiency of ferrochelatase (FECH, EC 4.99.1.1). EPP is transmitted as an autosomal dominant disorder with an incomplete penetrance. Using haplotype segregation analysis, we have identified an intronic single nucleotide polymorphism (SNP), IVS3-48T/C, that modulates the use of a constitutive aberrant acceptor splice site. The aberrantly spliced mRNA is degraded by a nonsense-mediated decay mechanism (NMD), producing a decreased steady-state level of mRNA and the additional FECH enzyme deficiency necessary for EPP phenotypic expression. 相似文献
176.
通过对修建在黄土边坡上建筑的理论分析 ,给出了黄土边坡建筑的抗滑移设计方法 ,建立了各种抗滑设计的计算公式 ,并通过工程实例对黄土边坡建筑进行了抗滑移设计 ,取得了令人满意的结果 相似文献
177.
用恒载荷和恒夹头速度蠕变法研究了Zn 2 .5Al、Zn 5Al和Zn 10Al合金的超塑性。研究表明 ,Zn 5Al共晶合金的超塑性优于亚共晶合金Zn 10Al及过共晶合金Zn 2 .5Al,其优异的超塑性来源于细密的层片状共晶组织 (α +β)。Zn 5Al合金的组织全部为 (α+β)共晶体 ,变形抗力低 ,晶界滑移均匀 ;Zn 10Al合金的α/ β界面较Zn 5Al的少 ,超塑性也不如Zn 5Al的好 ;Zn 2 .5Al合金的组织为 (α +β) +β,(α +β)共晶体主要包含α/ β界面 ,超塑变形时易滑移 ,先共晶的 β相包含β/ β界面 ,超塑变形时不易发生滑移。随着拉伸速度的减小 ,合金的流变应力减小 ,延伸率增大。轧制变形量大的合金 ,其超塑性也好。 相似文献
178.
Schreiber A Stengel F Zhang Z Enchev RI Kong EH Morris EP Robinson CV da Fonseca PC Barford D 《Nature》2011,470(7333):227-232
The anaphase-promoting complex or cyclosome (APC/C) is an unusually large E3 ubiquitin ligase responsible for regulating defined cell cycle transitions. Information on how its 13 constituent proteins are assembled, and how they interact with co-activators, substrates and regulatory proteins is limited. Here, we describe a recombinant expression system that allows the reconstitution of holo APC/C and its sub-complexes that, when combined with electron microscopy, mass spectrometry and docking of crystallographic and homology-derived coordinates, provides a precise definition of the organization and structure of all essential APC/C subunits, resulting in a pseudo-atomic model for 70% of the APC/C. A lattice-like appearance of the APC/C is generated by multiple repeat motifs of most APC/C subunits. Three conserved tetratricopeptide repeat (TPR) subunits (Cdc16, Cdc23 and Cdc27) share related superhelical homo-dimeric architectures that assemble to generate a quasi-symmetrical structure. Our structure explains how this TPR sub-complex, together with additional scaffolding subunits (Apc1, Apc4 and Apc5), coordinate the juxtaposition of the catalytic and substrate recognition module (Apc2, Apc11 and Apc10 (also known as Doc1)), and TPR-phosphorylation sites, relative to co-activator, regulatory proteins and substrates. 相似文献
179.
María Catalina Ramírez Jaime Plazas Camilo Torres Juan Camilo Silva Luis Camilo Caicedo Miguel Angel González 《Systemic Practice and Action Research》2012,25(2):95-116
In several rural areas in Colombia there is a serious lack of water quality supply. Thereby the problematic situation is understood
as complex one that involves stakeholders with pluralistic interests, multiple variables and requires the development of sustainable
and suitable solutions. In order to address this issue, this paper proposes an integration of engineering design framework
(CDIO) with a systemic approach. Particularly the approach emphasizes on systemic elements such as autonomy, systems within
systems, cooperation between stakeholders and cause effect relations; it also proposes a previous observing phase for engineering
design framework. Thus the proposed systemic framework aims to generate projects that improve living conditions in rural communities
and promote the production of knowledge between the stakeholders to ensure sustainability in the long term. To illustrate
the proposal, this work contains a case study that discusses a project carried out by a research team—Ingenieros Sin Fronteras Colombia—in a rural district near to Colombia’s capital. The experience, which involved and benefited 16 families in the community,
provided strong evidence to support the proposed framework. The paper concludes with a discussion about the replication of
this proposal in other contexts. 相似文献
180.
Separability of clusters is an issue that arises in many different areas, and is often used in a rather vague and subjective
manner. We introduce a combinatorial notion of interiority to derive a global view on separability of a set of entities. We
develop this approach further to evaluate the overall separability of a partition in the context of cluster analysis. Our
approach captures combinatorial and geometrical aspects of data and provides, in addition to numerical evaluations, graphical
representations particularly useful when data are not easily visualized. We illustrate the methodology on some real and simulated
datasets. 相似文献