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Stereotype formation may be based on the exaggeration of real group differences (category accentuation) or the misperception of group differences that do not exist (illusory correlation). This research sought to account for both phenomena with J. K. Kruschke's (1996, 2001, 2003) attention theory of category learning. According to the model, the features of majority groups are learned earlier than the features of minority groups. In turn, the features that become associated with a minority are those that most distinguish it from the majority. This second process is driven by an attention-shifting mechanism that directs attention toward group-attribute pairings that facilitate differentiation of the two groups and may lead to the formation of stronger minority stereotypes. Five experiments supported this model as a common account for category accentuation and distinctiveness-based illusory correlation. Implications for the natures of stereotype formation, illusory correlation, and impression formation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Ohne Zusammenfassungitteilung aus dem Government Laboratory of Victoria in Melbourne (Australien)  相似文献   
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Polybenzimidazole fibers, with an average diameter of 262 nm, were produced by the process of electrospinning. These fibers were used as a solid support material for the immobilization of oxovanadium(IV) which was achieved via a reaction with vanadyl sulfate. The oxovanadium(IV)‐functionalized nanofibers were used as heterogeneous catalysts for the oxidation of thioanisole under both batch and pseudo‐continuous flow conditions with great success. Under batch conditions near quantitative oxidation of thioanisole was achieved in under 90 min, even after four successive catalytic reactions. Under continuous conditions, excellent conversion of thioanisole was maintained throughout the period studied at flow rates of up to 2 mLh?1. This study, therefore, proposes that electrospun polybenzimidazole nanofibers, with their small diameters, impressive chemical and thermal stability, as well as coordinating benzimidazole group, may be a desirable support material for immobilization of homogeneous catalysts. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
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Hydrogen (H2) fuel obtained via thermo-catalytic ammonia (NH3) decomposition is rapidly attracting considerable interest for portable and distributed power generation systems. Consequently, a variety of reactor technologies are being developed in view of the current lack of infrastructure to generate H2 for proton exchange membrane (PEM) fuel cells. This paper provides an extensive review of the state-of-the-art reactor technology (also referred to as reactor infrastructure) for pure NH3 decomposition. The review strategy is to survey the open literature and present reactor technology developments in a chronological order. The primary objective of this paper is to provide a condensed viewpoint and basis for future advances in reactor technology for generating H2 via NH3 decomposition. Also, this review highlights the prominent issues and prevailing challenges that are yet to be overcome for possible market entry and subsequent commercialization of various reactor technologies. To our knowledge, this work presents for the first time a review of reactor infrastructure for distributed H2 generation via NH3 decomposition. Despite commendable research and development progress, substantial effort is still required if commercialization of NH3 decomposition reactor infrastructure is to be realized.  相似文献   
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We use elementary variational arguments to prove, and improve on, gap estimates which arise in simulating quantum circuits by adiabatic evolution. Partially supported by the National Science Foundation under Grant DMS-0314228 and by the National Security Agency and Advanced Research and Development Activity under Army Research Office contract number DAAD19-02-1-0065.  相似文献   
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The erythroleukaemic cell line TF-1, infected with either the pBabe neo retrovirus or the retrovirus bearing the human erythropoietin (hEpo) gene, developed three growth factor-independent clones. Erythropoietin (Epo), interleukin-3 (IL-3) and granulocyte-macrophage colony stimulating factor (GM-CSF) accelerated the proliferation of these clones. Autonomous growth of the clones was independent of Epo because it was not altered by Epo anti-sense oligonucleotides, nor was Epo detectable in culture supernatants. Cells from the mutant clones could not be induced by Epo to express glycophorin A and haemoglobin synthesis was markedly reduced. Haemin reversed the block in Epo-induced haemoglobin synthesis. Acquisition of growth factor-independence appears to be linked with the selective loss of differentiation capacity. These cells may provide a useful model for the study of the mechanisms involved in leukaemic transformation.  相似文献   
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The gastric brushings (GBRs) and endoscopic biopsies obtained concurrently from 27 patients in whom malignant lymphoma was diagnosed or suggested by either modality were assessed to evaluate the utility of cytologic examination in the diagnosis of gastric lymphoma. GBRs provided a definitive diagnosis of lymphoma in 2 (28%) of 7 patients with a prior history of lymphoma and 10 (56%) of 18 patients with primary gastric lymphoma, yielding an overall sensitivity of 48%. All the lymphomas diagnosed cytologically were large cell type. GBRs were suspicious for a malignant neoplasm in four lymphoma patients whose concurrent biopsies were negative. GBRs obtained from two patients who had gastritis were reported as suspicious for lymphoma. There were no false-positive diagnoses.  相似文献   
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Evolution of reactive oxygen species (ROS), generated during the patho-physiological stress of nervous tissue, has been implicated in the etiology of several progressive human neurological disorders including Alzheimer's disease (AD) and amylotrophic lateral sclerosis (ALS). In this brief communication we used mixed isomers of 5-(and-6)-carboxy-2',7'-dichlorofluorescein diacetate (carboxy-DCFDA; C(25)H(14)C(l2)O(9); MW 529.3), a novel fluorescent indicator, to assess ROS generation within human neuronal-glial (HNG) cells in primary co-culture. We introduced pathological stress using the sulfates of 12 environmentally-, industrially- and agriculturally-relevant divalent and trivalent metals including Al, Cd, Cu, Fe, Hg, Ga, Mg, Mn, Ni, Pb, Sn and Zn. In this experimental test system, of all the metal sulfates analyzed, aluminum sulfate showed by far the greatest ability to induce intracellular ROS. These studies indicate the utility of using isomeric mixtures of carboxy-H(2)DCFDA diacetates as novel and highly sensitive, long-lasting, cell-permeant, fluorescein-based tracers for quantifying ROS generation in intact, metabolizing human brain cells, and in analyzing the potential epigenetic contribution of different metal sulfates to ROS-generation and ROS-mediated neurological dysfunction.  相似文献   
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