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71.
Hofmann Wilhelm; De Houwer Jan; Perugini Marco; Baeyens Frank; Crombez Geert 《Canadian Metallurgical Quarterly》2010,136(3):390
This article presents a meta-analysis of research on evaluative conditioning (EC), defined as a change in the liking of a stimulus (conditioned stimulus; CS) that results from pairing that stimulus with other positive or negative stimuli (unconditioned stimulus; US). Across a total of 214 studies included in the main sample, the mean EC effect was d = .52, with a 95% confidence interval of .466–.582. As estimated from a random-effects model, about 70% of the variance in effect sizes were attributable to true systematic variation rather than sampling error. Moderator analyses were conducted to partially explain this variation, both as a function of concrete aspects of the procedural implementation and as a function of the abstract aspects of the relation between CS and US. Among a range of other findings, EC effects were stronger for high than for low contingency awareness, for supraliminal than for subliminal US presentation, for postacquisition than for postextinction effects, and for self-report than for implicit measures. These findings are discussed with regard to the procedural boundary conditions of EC and theoretical accounts about the mental processes underlying EC. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
C.P. Marcel M. Rohde V.P. Masson T.H.J.J. Van der Hagen 《International Journal of Heat and Mass Transfer》2009,52(21-22):5046-5054
The use of supercritical water as coolant/moderator may induce oscillations in the supercritical light water reactor similar to the density wave oscillations observed in boiling water reactors (BWRs). In order to experimentally investigate the stability of supercritical reactors, a fluid-to-fluid downscaled facility is proposed. It is found that with an appropriate mixture of refrigerants R-125 and R-32, the dimensionless enthalpy and density of the supercritical water can be accurately matched for all relevant operational conditions of the reactor. Moreover, the inertia distribution, the friction factor distribution and the heat transfer mechanism are taken into account in the modeling. As a result of the proposed downscaling, the operational pressure, temperature and power are considerably smaller than those of a water-based system, which in turn helps reducing the construction and operational costs of a test facility. Finally, it is found that the often used modeling fluid supercritical CO2 cannot accurately represent supercritical water at reactor conditions. 相似文献
73.
In the present study, we investigate the two-dimensional laminar flow through a one-sided constriction of a plane channel with a ratio of h:H=1:4 (where h is the step height and H is the channel height). The computational approach employed is based on a mixed implicit/explicit time discretization scheme together with a highly accurate spatial discretization using a P
N
–P
N–2 spectral-element method. It is well known that this so-called forward-facing step (FFS) flow exhibits a singularity in the pressure and the velocity derivatives at the corner point. We account for this singularity by a geometric mesh refinement strategy that was proposed in a hp-FEM context. A detailed numerical study of the FFS flow reveals that length and height of the recirculation zone in front of the step are almost constant for creeping flow. In the limit of high Reynolds numbers the length and height of the recirculation zone increase proportional to Re
0.6 and Re
0.2, respectively. 相似文献
74.
Dr.-Ing. Wilhelm Spruth 《Electrical Engineering (Archiv fur Elektrotechnik)》1958,43(7):427-449
Ohne ZusammenfassungMit 47 AbbildungenDie vorliegende Arbeit ist ein Auszug aus der Dissertation des Verfassers (Technische Hochschule Aachen 1956/57). 相似文献
75.
Al-Lahham A Rohde V Heim P Leuchter R Veeck J Wunderlich C Wolf K Zimmermann M 《Yeast (Chichester, England)》1999,15(5):385-396
By complementation screening of a cadmium-sensitive Schizosaccharomyces pombe mutant deficient in phytochelatin synthesis, but with 44% of the wild-type glutathione content, we cloned a DNA fragment involved in phytochelatin synthesis. Sequence analysis revealed that it encodes the second enzyme involved in glutathione (GSH) biosynthesis, glutathione synthetase (GSH2) (E.C.6.3.2.3, Wang and Oliver, 1997). The mutant allele shows a single base-pair exchange at the 3' end of the reading frame leading to a single amino acid change from glycine to aspartate. This mutation leads to a significant reduction of phytochelatin synthesis, whereas glutathione synthesis is impaired to a far lesser extent. Complementation with the Arabidopsis thaliana GSH2 cDNA led to a partial restoration of phytochelatin synthesis. These data strongly suggest that the GSH2 gene encodes a bifunctional enzyme that is able to catalyse both the synthesis of GSH by adding glycine to the dipeptide (gammaGlu-Cys) and the synthesis of phytochelatins. The sequence has been submitted to EMBL, Accession No. Y08414. 相似文献
76.
K Fischer V Lutz O Wilhelm M Schmitt H Graeff P Heiss T Nishiguchi N Harbeck H Kessler T Luther V Magdolen U Reuning 《Canadian Metallurgical Quarterly》1998,438(1-2):101-105
It has been well established that the cytoskeleton is an essential modulator of cell morphology and motility, intracytoplasmic transport and mitosis, however cytoskeletal linkage to the organelles has not been unequivocally demonstrated. Indeed, cytoskeleton appears to be essential in determining and modulating gene phenotype as a function of cellular environment. According to recent studies, the organization of the cytoskeleton network together with associated protein(s) could be essential in regulating mitochondrial function and particularly the permeability of the mitochondrial outer membrane to ADP. The aim of this chapter is to summarize the main properties of the cytoskeletal environment of mitochondria and the possible role(s) of this network in mitochondrial function in myocytes. 相似文献
77.
78.
Distraction-lengthening technique is quite useful in a variety of congenital hand deformities with hypoplastic, or primary normal but secondary shortened (constriction ring syndrome) finger rays. It appears that around the age of two years is the earliest practical time to start distraction; certainly distraction and secondary surgical procedures to improve function should be completed before school entry age whenever possible. Between June 1990 and March 1993, nine distraction lengthening procedures (5 thumbs, 1 index, 3 little fingers) in five patients presenting with congenital hand deformities, were carried out. Although restoring length to the finger, lengthening does not provide normal circumference or, of course, interphalangeal joint motion. Amelioration in function seems to be more important than the esthetic gain. Distraction lengthening tolerates only few errors of indication, operative technique, and/or postoperative management. A high compliance of the patient and her/his parents as well as a close follow-up by an experienced surgeon, are mandatory for a good result. A variety of possible complications have been described. Generally, complication risk increases in cases of simultaneous and multiple level lengthening. Provided adequate operative technique and postoperative care, superficial pin infection and fracture in the region of distraction are the major complications. Contrary to adults, sufficient bone formation by distraction is the rule in children. Therefore, the distraction-lengthening technique is preferred to the distraction-interposition technique in the treatment of congenital hand deformities. The latter should only be used as a salvage procedure in the rare cases of insufficient callus formation. Because of the missing growth potential and reduced joint mobility, distraction lengthening is the therapy of second choice when compared to microvascular second toe transplantation. 相似文献
79.
Rosin and hydroxymethyl derivatives of rosin acids react rapidly with commercially available glycidyl ethers to give the hydroxy
monoesters of aliphatic ethers. These esters of rosin, oxonated rosin and tetrahydroabietic acid are viscous liquids of low
acid number and high hydroxyl number with a light to golden amber color. In the case of 12-hydroxymethyltetrahydroabietic
acid, the products are colorless gums of a tacky, semisolid consistency. The acid, hydroxyl and saponification values, and
the viscosities and softening points are tabulated.
So. Utiliz. Res. Dev. Div., ARS, USDA 相似文献
80.
Beschreibung der Versuchsapparatur zur Messung der Thermospannung der Kette Rh |T + Δ AIN |T Rh für Temperatur-differenzen bis zu ± 60 °C zwischen 1350 und 1650 °C. Ermittlung der Thermokraft und ihres homogenen Anteils. Berechnung der Überführungswärme der wandernden Ionen aus der homogenen Thermokraft. Erörterung zum Leitungsmechanismus im Aluminiumnitrid AlN. 相似文献