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991.
992.
This article summarizes a review of the careers of 50 executives who have been outstanding in traversing the careers of their professional lives. In a world of short job tenure-elongated middle age, most executives will have to simultaneously manage two separate careers. One career is called full-time assignment work and is the traditional "job." The other career is called project assignment work, also known as interim or consulting work. Many think these two careers will occur sequentially. This typical framework sets leaders up for perceived failure because this sequential model is no longer realistic. Leaders will be traversing between full time and project based work through their professional lives. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Portable datafile technologies such as high density bar coding and electronic tagging now permit very high information storage capacities. Aside from anecdotal evidence, there are few examples of these technologies being used within construction. This paper explores the potential advantages of using portable datafiles for storing and transmitting information relating to construction materials and components. A structured methodology is presented to aid the definition of (1) information which could be encoded within labels or tags; and (2) the stages within the supply chain where such a device would most fruitfully be employed. A case study is presented which demonstrates both the operational and financial feasibility of using portable datafiles within the scenario of a live project. Recommendations are made for the development of a construction industry standard for portable datafiles as part of a framework to promote more widespread deployment of the technologies. Les fichiers de donnees portables comme les codes a barres et l'etiquetage electronique sont des technologies qui autorisent de tres hautes capacites de stockage de l'information. A part l'evidence anecdotique, on compte peu d'exemples de l'utilisation de ces technologies dans le secteur de la construction. Dans cet article l'auteur explore les avantages potentiels de l'utilisation des fichiers de donnees portables pour le stockage et la transmission des informations se rapportant aux materiaux et equipements de construction. Il expose une methodologie structuree destinee a faciliter la definition de l'information qui peut etre codee dans des etiquettes ainsi que des etapes dans la chaine d'approvisionnement ou de tels systemes seraient particulierement utiles. Une etude de cas est presentee demontrant la faisabilite operationnelle et financiere de l'utilisation de fichiers de donnees portables dans le cadre d'un projet concret. L'auteur fait des recommandations en vue de l'elaboration d'une norme industrielle portant sur l'utilisation de fichiers portables dans le secteur de la construction, l'objectif etant de promouvoir davantage encore le deploiement de ces technologies. 相似文献
994.
This article reviews the research evidence for the efficacy of cognitive-behavioral therapy (CBT) for somatoform disorders. Randomized controlled studies support the efficacy of individual CBT for the treatment of hypochondriasis, body dysmorphic disorder (BDD), and undifferentiated somatoform disorders including medically unexplained symptoms, chronic fatigue syndrome, and noncardiac chest pain, and group CBT for the treatment of BDD and somatization disorder. On the basis of this review of the existing research and a theoretical model of the processes involved in somatoform disorders, the authors offer suggestions for future research and effective treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
995.
Chemokines (chemotactic cytokines) are a family of immune system proteins, several of which have been shown to block human immunodeficiency virus (HIV) infection in various cell types. While the solved structures of most chemokines reveal protein dimers, evidence has accumulated for the biological activity of individual chemokine monomers, and a debate has arisen regarding the biological role of the chemokine dimer. Concurrent with this debate, several N-terminal truncations and modifications in the CC subfamily of chemokines have been shown to have functional significance, in many cases antagonizing their respective receptors and in some cases retaining the ability to block HIV entry to the cell. As the dimer interface of CC chemokines is located at their N-terminus, a structural study of N-terminally truncated chemokines will address the effect that this type of mutation has on the dimer-monomer equilibrium. We have studied the structural consequences of N-terminal truncation in macrophage inflammatory protein 1 beta (MIP-1 beta), a CC chemokine that has been shown to block HIV infection. Examination of nuclear magnetic resonance (NMR) spectra of a series of N-terminally truncated MIP-1 beta variants reveals that these proteins possess a range of ability to dimerize. A mutant beginning at amino acid Asp6 [termed MIP(6)] has near wild-type dimer properties, while further truncation results in weakened dimer affinity. The mutant MIP(9) (beginning with amino acid Thr9) has been found to exist solely as a folded monomer. Relaxation measurements yield a rotational correlation time of 8.6 +/- 0.1 ns for wild-type MIP-1 beta and 4.5 +/- 0.1 ns for the MIP(9) mutant, consistent with a wild-type dimer and a fully monomeric MIP(9) variant. The presence of physiological salt concentration drastically changes the monomer-dimer equilibrium for both wild-type and most mutant proteins, heavily favoring the dimeric form of the protein. These results have implications for structure-function analysis of existing chemokine mutants as well as for the larger debate regarding the biological existence and activity of the chemokine dimer. 相似文献
996.
We report the crystal structure of nucleoside diphosphate kinase (NDP kinase) from Dictyostelium discoideum with thymidine diphosphate (dTDP) and Mg2+ bound at the active site. The structure has been refined to an R-factor of 18.3% at 2-A resolution. The base stacks on the aromatic ring of Phe 64 near the protein surface and is wedged between the side chains of Phe 64 and Val 116. The sugar and the pyrophosphate are deeper inside the protein and make numerous H-bonds with protein side chains. There is no backbone interaction with the nucleotide. A Mg2+ ion bridges the alpha- and beta-phosphates and interacts with the protein via water molecules. NDP kinase shows little specificity toward ribonucleotides and deoxyribonucleotides. This property, required by the enzyme biological function, can now be analyzed by comparing the crystal structures of free, ADP-ligated, and dTDP-ligated enzymes. The most significant differences are located in residues 60-64, which adapt their conformation to allow Phe 64 to stack on both types of bases. Nonspecific binding is achieved by the absence of polar interaction between the base and protein atoms. The ribose of ADP and the deoxyribose of dTDP occupy similar positions, their hydroxyl groups interacting with Lys 16 and Asn 119. The H-bond between Lys 16 and the O2' hydroxyl of ADP is replaced by a similar interaction with a water molecule in the dTDP complex. The beta-phosphate position is the same for ADP and dTDP, suggesting that the mechanism of phosphate transfer is the same for all substrates ofNDP kinase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
997.
Hyunjung Kim Zhang Jiang Young Joo Lee Laurence Lurio S.K. Sinha 《Thin solid films》2007,515(14):5536-5540
We have applied X-ray photon correlation spectroscopy (XPCS) to measure the surface dynamics of polymer films of thicknesses down to a few times of the polymer radius of gyration. XPCS is currently the only technique to measure selectively dynamics of surface and/or interfacial fluctuations of the films thanks to high brilliance and coherence of the third generation synchrotron source. The results show the behavior of the capillary waves expected in viscous liquid when the film thickness is thicker than four times of the radius of gyration. However, thinner films show a deviation indicating the need to account for viscoelasticity. We present also the theory for surface dynamics of the thermally excited fluctuations on homogenous single-layer film with arbitrary depth is generalized to describe surface and interfacial dynamics of polymeric liquid bilayer films in terms of susceptibilities, power spectra and characteristic relaxation time constants. The effects on surface dynamics originating from viscosity inhomogeneities close to surface region are investigated by the bilayer theory and compared with the surface dynamics from homogeneous single-layer films under non-slip and slip boundary conditions. 相似文献
998.
Canter David V.; Alison Laurence J.; Alison Emily; Wentink Natalia 《Canadian Metallurgical Quarterly》2004,10(3):293
Despite weaknesses in the organized/disorganized classification of serial killers, it is drawn on for "offender profiles," theories of offending, and in murder trials. This dichotomy was therefore tested by the multidimensional scaling of the co-occurrence of 39 aspects of serial killings derived 100 murders committed by 100 U.S. serial killers. Results revealed no distinct subsets of offense characteristics reflecting the dichotomy. They showed a subset of organized features typical of most serial killings. Disorganized features are much rarer and do not form a distinct type. These results have implications for testing typologies supporting expert opinion or to help understand variations in criminal acts, as well as the development of a science of investigative psychology that goes beyond offender profiling. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Smith Laurence D.; Best Lisa A.; Stubbs D. Alan; Archibald Andrea Bastiani; Roberson-Nay Roxann 《Canadian Metallurgical Quarterly》2002,57(10):749
Because graphs provide a compact, rhetorically powerful way of representing research findings, recent theories of science have postulated their use as a distinguishing feature of science. Studies have shown that the use of graphs in journal articles correlates highly with the hardness of scientific fields, both across disciplines and across subfields of psychology. In contrast, the use of tables and inferential statistics in psychology is inversely related to subfield hardness, suggesting that the relationship between hardness and graph use is not attributable to differences in the use of quantitative data in subfields or their commitment to empiricism. Enhanced "graphicacy" among psychologists could contribute to the progress of psychological science by providing alternatives to significance testing and by facilitating communication across subfields. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Functional properties of caseinate glycoconjugates prepared by controlled heating in the ‘dry’ state
Christine M Oliver Laurence D Melton Roger A Stanley 《Journal of the science of food and agriculture》2006,86(5):732-740
Glucose, ribose, fructose, lactose, fructo‐oligosaccharide (inulin) and a mixture of inulin and fructose were conjugated with caseinate via the Maillard reaction using controlled heating and low water activity conditions in order to improve the functional properties of caseinate for food purposes. Conjugation with ribose and glucose increased the viscosity of caseinate 28‐fold over that of the unmodified caseinate control but also produced the most browning. Glycoconjugates of caseinate–fructose reacted at a substrate ratio of 1:0.2 w/w and 60 °C at 67% relative humidity for 48 h increased the viscosity of caseinate 24‐fold with less browning. At 80% relative humidity the reaction occurred so rapidly that, within 24 h gels containing darkly coloured particulate matter were produced. Incorporation of inulin at 1:1:0.2 w/w/w caseinate/inulin/fructose prevented formation of gels and produced glycoconjugates having 15‐fold the viscosity of unmodified caseinate with minimal browning. Copyright © 2005 Society of Chemical Industry 相似文献