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排序方式: 共有409条查询结果,搜索用时 15 毫秒
31.
Mordasini T Curioni A Bursi R Andreoni W 《Chembiochem : a European journal of chemical biology》2003,4(2-3):155-161
An unambiguous understanding of the binding mode of human progesterone to its receptor still eludes experimental search. According to the X-ray structure of the ligand-binding domain, only one (O3) of the two keto groups at the ligand ends (O3 and O20) should play a role. This result is in conflict with chemical intuition and the results of site-directed mutagenesis experiments. Herein, we report classical molecular dynamics simulations that reveal the dynamic nature of the binding in solution, elucidate the reasons why X-ray studies failed to determine the role of O20, and clarify the effects of the mutations. The predictive power of the force field is ensured by the consistent introduction of a first-principles representation of the ligand. 相似文献
32.
The Cognitive Interview (CI) is a well-established protocol for interviewing witnesses. The current article presents a study space analysis of laboratory studies of the CI together with an empirical meta-analysis summarizing the past 25 years of research. The study space comprises 57 published articles (65 experiments) on the CI, providing an assessment of the boundary conditions underlying the analysis and application of this interview protocol. The current meta-analysis includes 46 published articles, including 20 articles published since the last meta-analysis conducted a decade earlier (K?hnken, Milne, Memon, & Bull, 1999). Reassuringly for practitioners, the findings of the original meta-analysis were replicated with a large and significant increase in correct details and a small increase in errors. In addition we found that there were no differences in the rate at which details are confabulated. Importantly, the effect sizes were unaffected by the inclusion of recent studies using modified versions of the CI. The CI appeared to benefit older adult witnesses even more than younger adults. We highlight trends and gaps in research and discuss how our findings can inform policy and training decisions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
T. Meissner S. K. Goh J. Haase B. Meier D. Rybicki P. L. Alireza 《Journal of Low Temperature Physics》2010,159(1-2):284-287
A novel approach that uses radio-frequency microcoils in the high-pressure region of anvil cells with Nuclear Magnetic Resonance (NMR) experiments is described. High-sensitivity Al NMR data at 70 kbar for Al metal are presented for the first time. An expected decrease in the Al Knight shift at 70 kbar is observed, as well as an unexpected change in the local charge symmetry at the Al nucleus. The latter is not predicted by chemical structure analysis under high pressure. 相似文献
34.
K. Proke Th. Wand A.V. Andreev M. Meissner F. Honda V. Sechovský 《Journal of Alloys and Compounds》2008,460(1-2):47-53
Specific heat of a single crystalline URhSi was measured by a relaxation method in a temperature range 0.3–25 K in magnetic fields up to 8 T applied along the two of the principal axes. The low-temperature specific heat exponentially decays with magnetic field. The decay is much faster in fields applied along the easy magnetization direction (the c-axis) than for the hard axis (the a-axis) case. A strong upturn in cp/T versus T below 0.6 K that disappears with application of magnetic field is observed suggesting possible magnetic or superconducting phase transition at lower temperatures. The electrical resistivity in the vicinity of the ferromagnetic phase temperature is found to be reduced by more than 50% upon application of magnetic field of 8 T applied along the c-axis. URhSi represent an itinerant ferromagnetic system with influence of spin fluctuations. 相似文献
35.
New polythioesters by interfacial polycondensation of 1,4-dimercaptomethyl–tetramethylbenzene with oxalyl, succinyl, adipoyl, suberoyl, sebacoyl, and isomeric phthaloyl dichlorides were obtained. To define the optimal conditions for interfacial polycondensation, the influence of the following factors on yield and value of reduced viscosity were studied: type of organic phase, concentration of hydrogen chloride acceptor, the quantitative ratio of aqueous to organic phase, molar ratio of reagents rate of acid chloride addition, contribution of benzyltriethylammonium chloride as a catalyst, and the temperature of the reaction. Thorough studies were carried out only for polycondensation of the dithiol with adipoyl, sebacoyl, and isophthaloyl chlorides. The structure of polythioesters obtained under the model conditions was determined by elementary analysis and infrared spectra. Initial decomposition temperature, mass loss in percentage at the same temperature, maximum rate of decomposition, and mass loss percentage at 100–400°C were defined from the curves of thermogravimetric analysis. Chemical resistance of the polythioesters was determined by treatment with some organic solvents, mineral acids (concentrated and 10%) and sodium hydroxide (10% and 50%). The molecular weight was not measured because of the low solubility of the polythioesters. 相似文献
36.
Sebastian Meissner 《Datenschutz und Datensicherheit - DuD》2008,32(8):525-531
Qualitativ hochwertige Zertifizierungskriterien sind eine fundamentale Voraussetzung für den Erfolg und die Reputation eines
Gütesiegels. Dies gilt auch und gerade für das zurzeit im Rahmen des Projekts EuroPriSe (European Privacy Seal) konzipierte
und erprobte europ?ische Datenschutzgütesiegel. Der Beitrag beschreibt, wie bei der Entwicklung der EuroPriSe-Kriterien vorgegangen
worden ist, und stellt die einschl?gigen Zertifizierungskriterien in einem überblick vor. 相似文献
37.
This article is written on behalf of the Society for Industrial and Organizational Psychology (SIOP) to present its reactions to the "Principles for Education and Training at the Doctoral and Postdoctoral Level in Consulting Psychology/Organizational" (R. L. Lowman et al, Education and Training Committee, see record 2003-04049-003). An overview of the history and practice of industrial-organizational psychology is provided. The Consulting Principles are then compared with SIOP Education and Training Guidelines (SIOP Guidelines, 1985 and 1999), and recommendations are made for enhancements to the Consulting Principles. The primary recommendation is for the addition of a second tier of competencies focusing on the knowledge, skill, and abilities that underlie the types of work described in the Individual-, Group-, and Organizational-Level Competencies. As an alternative, the Consulting Principles could focus on consulting skills and refer to the appropriate APA divisions regarding specialty areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
39.
Enning B. Vodhanel R.S. Dietrich E. Patzak E. Meissner P. Wenke G. 《Lightwave Technology, Journal of》1989,7(3):459-464
Polarization diversity is an alternative technique for coherent receivers to prevent loss to signal due to variations in the states of polarization (SOP) of the received signal field. It is shown experimentally and theoretically that there is no significant power penalty difference between a receiver with optimally adjusted gains and receivers with linear envelope detection and square-law detection. Experimentally, two amplitude-shift keying (ASK) heterodyne polarization diversity receivers with envelope detectors were demonstrated at 560 Mb/s, one using linear rectifiers, the other using square-law rectifiers. In both cases, the receiver sensitivity of -35 dBm at BER=10 -9 was degraded by less than 1 dB as the received signal SOP was varied, in agreement with theory 相似文献
40.
Ching T. Hou Harold Gardner Wanda Brown 《Journal of the American Oil Chemists' Society》1998,75(11):1483-1487
Hydroxy fatty acids are important industrial materials. We isolated a microbial culture, Clavibacter sp. ALA2, which converts linoleic acid to many polyhydroxy fatty acids. Structures of the products were determined as: 12,13,17-trihydroxy-9(Z)-octadecenoic
(THOA, main product), 12-[5-ethyl-2-tetrahydrofuranyl]-7,12-dihydroxy-9(Z)-dodecenoic (ETDDA), and 12-[5-ethyl-2-tetrahydrofuranyl]-12-hydroxy-9(Z)-dodecenoic
(ETHDA) acid. The yield of THOA was 25% and the relative amount of the products were THOA/ETDDA/ETHDA =9:1.3:1. The structures
of the hydroxy unsaturated fatty acids resemble those of plant self-defense substances. 相似文献