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31.
Recent work on minority influence has led to a debate about whether majorities and minorities exercise different forms of influence. C. L. Nemeth (see record 1986-14271-001) has argued that consistent minorities induce different cognitive processes than do consistent majorities, with a resulting impact on the quality of the judgments rendered. Two experiments test this theory. In Experiment 1, Ss heard 3 tape-recorded lists of words and learned that either a minority or a majority differed in the category "first noticed." This feedback occurred either once or over 3 trials. When exposure was once, recall was not affected by the source; when it was consistent, Ss exposed to the minority view recalled more words than those exposed to the majority view. In Experiment 2, Ss were exposed to a minority view that was either consistent over time or inconsistent over time. Ss exposed to a consistent minority had better recall than control Ss. Exposure to an inconsistent minority did not improve recall. The results offer support for the Nemeth formulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Layer-type microcrystalline powders of WS2, MoS2, WSe2 and MoSe2, which were tested for photoeffects with contact free microwave conductivity measurements, were incorporated into a nanostructured TiO2 matrix in an attempt to obtain macroscopic photocurrents. Even though only 10% of the microcrystals were found to be active in contact with an iodide/iodine solution, photocurrents of the order of 100 μA/cm2 to 1 mA/cm2 were measured. The photoelectrochemical behavior of microcrystals was studied with space resolved photocurrent and photovoltage measurement techniques and it was attempted to understand the mechanism of current generation via the TiO2/microcrystal/electrolyte interaction. Critical and still unresolved problems are recognized to be the control and optimization of photoeffects in microcrystals and the adjustment of doping levels of the two material faces. Only small photopotentials could be observed up to now, probably due to an insufficient and inhomogeneous doping of microcrystals. More research will be needed to determine whether this strategy could lead to realistic photovoltaic systems.  相似文献   
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Blind and blindfolded sighted observers were presented with auditory stimuli specifying target locations. The stimulus was either sound from a loudspeaker or spatial language (e.g., "2 o'clock, 16 ft"). On each trial, an observer attempted to walk to the target location along a direct or indirect path. The ability to mentally keep track of the target location without concurrent perceptual information about it (spatial updating) was assessed in terms of the separation between the stopping points for the 2 paths. Updating performance was very nearly the same for the 2 modalities, indicating that once an internal representation of a location has been determined, subsequent updating performance is nearly independent of the modality used to specify the representation. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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The 5-HTTLPR is an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene. Prior research has revealed associations between the short-allele variant of this polymorphism, enhanced self-reported negative emotionality, and hypersensitivity of fear relevant neural circuits. In a sample of 50 healthy women we examined the role of 5-HTTLPR for cognitive-affective processing of phylogenetical fear-relevant stimuli (spiders) in a dot probe task. In contrast to homozygote long-allele carriers (ll), participants carrying at least 1 short allele (ss and sl) selectively shifted attention toward pictures of spiders, when these were presented for a duration of 2,000 ms. These results argue for an involvement of 5-HTTLPR in cognitive processing of threatening stimuli and thus, underpin its general role for individual differences in negative affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Fiber scaffolds of bioactive polysialic acid have been prepared via electrospinning for peripheral nerve regeneration. The diameter, morphology and alignment of fibers in scaffolds were adjusted by variation of electrospinning parameters, which are decisive for the cell-scaffold interaction. Due to the high water solubility of polysialic acid (poly-α-2,8-N-acetylneuraminic acid) a photoactive derivative (poly-α-2,8-N-pentenoylneuraminic acid) was used to obtain stable fiber scaffolds in water by photochemical crosslinking. At the optimized fiber scaffolds good cell viability and directed cell proliferation along the fibers was achieved by cell tests with immortalized Schwann cells.  相似文献   
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In recent years competitive pressure in mobile markets has increased remarkably. New business models and thus new actors have entered the market. This contribution analyzes the reconfiguration of value structures and strategies in mobile markets. For this purpose, mobile network operators?? service portfolio is analyzed on the basis of a worldwide survey, and the relevant current and future value creation activities are identified with consideration of additional actors and influence factors. On that basis, roles are developed, linked with regard to value flows and combined to a reference model for the mobile market value net. Subsequently, scenario planning is used to develop a set of criteria for the construction of corresponding future scenarios and the application of the reference model is demonstrated with such a scenario.  相似文献   
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•  This article develops a conceptual framework to assist in determining the value to be gained from long-term international assignments.  相似文献   
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