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11.
This review describes the properties of some rare eukaryotic chaperones that each assist in the folding of only one target protein. In particular, we describe (1) the tubulin cofactors, (2) p47, which assists in the folding of collagen, (3) α-hemoglobin stabilizing protein (AHSP), (4) the adenovirus L4-100 K protein, which is a chaperone of the major structural viral protein, hexon, and (5) HYPK, the huntingtin-interacting protein. These various-sized proteins (102–1,190 amino acids long) are all involved in the folding of oligomeric polypeptides but are otherwise functionally unique, as they each assist only one particular client. This raises a question regarding the biosynthetic cost of the high-level production of such chaperones. As the clients of faithful chaperones are all abundant proteins that are essential cellular or viral components, it is conceivable that this necessary metabolic expenditure withstood evolutionary pressure to minimize biosynthetic costs. Nevertheless, the complexity of the folding pathways in which these chaperones are involved results in error-prone processes. Several human disorders associated with these chaperones are discussed.  相似文献   
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Formal systems engineering approaches to modeling misperceptions and attitudes are employed within the framework of the graph model for conflict resolution to systematically study the War of 1812 between the United States of America and Great Britain in order to provide enhanced insights into the causes of the war. More specifically, relational definitions for preferences, movements and stability concepts are defined for describing the attitudes and associated behavior of decision makers involved in a conflict. To capture misperceptions of decision makers in the War of 1812, attitudes are studied within the structure of a hypergame. Combining attitudes and misperceptions within the paradigm of the graph model furnishes the flexible analytical tool which demonstrates that misunderstanding of attitudes by Great Britain and the United States may have contributed to the outbreak of this nasty war.  相似文献   
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An allowable generalized quantum gate (introduced by Long, Liu and Wang) has the form of U = Σ k=0 d−1 c k U k , where U k’s are unitary operators on a Hilbert space H and |Σ k=0 d−1 c k |⩽1 and |c k |⩽1 (0⩽kd−1). In this work we consider a kind of AGQGs, called restricted allowable generalized quantum gates (RAGQGs), satisfying 0 < Σ k=0 d−1|c k |⩽1. Some properties of the set RAGQG(H) of all RAGQGs on H are established. Especially, we prove that the extreme points of RAGQG(H) are exactly unitary operators on H and that B(H)=R + RAGQG(H).  相似文献   
14.
The process of 180° domain switching in PbTiO3 single crystal under an antiparallel electric field was investigated by the three-dimensional phase field simulation, especially the effect of electric field on the type and duration of domain switching. It is found that the polarization reversal of domains takes place under an antiparallel electric field in PbTiO3 single crystal. The results of the phase field simulation indicate that there is only 90° domain switching under a weak electric field. With the rise of the electric field, 180° domain switching appears. If the electric field is strengthened further, 90° domain switching disappears and the duration of domain switching is shortened.  相似文献   
15.
Co-operative inquiry is an under-explored method in community-based research. Its democratic approach involves a group of “co-researchers” collaboratively inquiring into a mutually-agreed research topic through systematic cycles of reflection and action. This article shares the process, outcomes, and methodological reflections of three co-operative inquiries that were conducted as part of an international study regarding love in community work. Groups of up to 10 community workers in rural villages in Timor-Leste, Australia, and Peru engaged in co-operative inquiry to collaboratively develop new knowledge to inform practice. The article analyses data regarding co-inquirer experiences of the methodology, and identifies the strengths and challenges of the co-operative inquiry method to support the collective generation of new knowledge. The article concludes that co-operative inquiry involves shared power, participation, action, and contextual reflexivity, and is a useful method for community workers to collaboratively develop innovative approaches to community work practice through cycles of reflection and action.  相似文献   
16.
In this study, China isolate HB of pseudorabies virus (PRV) was confirmed and genotypically characterized by amplifying and sequencing of partial UL34, a conservative gene involved in the egress of nucleocapsids from the nucleus, for phylogenetic analysis. The open reading frame (orf) of UL34 of PRV HB isolate is composed of 786 nucleotides, which encoded 262 amino acids. In addition, a potential transmembrane domain (241-260 aa) and 11 potential phosphorylation sites were also found in the UL34 of PRV HB isolate. Multiple amino acids alignment indicated that UL34 proteins of PRV strains derived from different geographic origins were highly conservative, but some mutations were also found. Phylogenetic analysis based on UL34 protein indicated that PRV HB strain was evolutionarily distinct from other recent China strains sequenced so far, forming a single clade within the phylogeny. Moreover, PRV HB isolate had close evolutionary relationship with BoHV-1 and BoHV-5 within the Alphaherpesvirinae. Taken together, these results indicated that PRV strains were in the progress of evolution. This study has expanded the knowledge of genetic profiles of PRV strains.  相似文献   
17.
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The electro-deoxidation of V2O3 precursors was studied. Experiments were carried out with a two-terminal electrochemical cell, which was comprised of a molten electrolyte of CaCl2 and NaCl with additions of CaO, a cathode of compact V2O3, and a graphite anode under the potential of 3.0 V at 1173 K. The phase constitution and composition as well as the morphology of the samples were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). 3 g of V2O3 could be converted to vanadium metal powder within the processing time of 8 h. The kinetic pathway was investigated by analyzing the product phase in samples prepared at different reduction stages. CaO added in the reduction path of V2O3 formed the intermediate product CaV2O4.  相似文献   
18.
Bi2Se3 thin films were electrochemically deposited on Ti and indium tin oxide-coated glass substrates, respectively, at room temperature, using Bi(NO3)3·5H2O and SeO2 as starting materials in diluted HNO3 solution. A conventional three-electrode cell was used with a platinum sheet as a counter electrode, and a saturated calomel electrode was used as a reference electrode. The films were annealed in argon atmosphere. The influence of cold isostatic pressing before annealing on the microstructure and thermoelectric properties of the films was investigated. X-ray diffraction analysis indicates that the film grown on the indium tin oxide-coated glass substrate is pure rhombohedral Bi2Se3, and the film grown on the Ti substrate consists of both rhombohedral and orthorhombic Bi2Se3.  相似文献   
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