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In tasks as diverse as stock market predictions and jury deliberations, a person's feelings of confidence in the appropriateness of different choices often impact that person's final choice. The current study examines the mathematical modeling of confidence calibration in a simple dual-choice task. Experiments are motivated by an accumulator model, which proposes that information supporting each alternative accrues on separate counters. The observer responds in favor of whichever alternative's counter first hits a designated threshold. Confidence can then be scaled from the difference between the counters at the time that the observer makes a response. The authors examine the overconfidence result in general and present new findings dealing with the effect of response bias on confidence calibration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The first pressurized-thermal-shock test of a 148 mm thick steel pressure vessel with a 1 m long flaw was performed to investigate fracture behavior of a vessel under conditions relevant to a flawed nuclear reactor pressure vessel during an overcooling accident. The objectives were to observe crack arrest and stability on the ductile upper shelf and the effects of warm prestressing on crack initiation. Three coordinated pressure and thermal transients were imposed on the vessel, which was preheated to 290°C. Two episodes of crack propagation and arrest occurred. The thermal transients were induced by coolant at −29 to 15°C. Pressure transients were as high as 94.4 MPa. The experimental objectives were attained. The inhibiting effects of warm prestressing were definitely demonstrated. Crack propagation was nearly pure cleavage, and arrest at 30 K above the onset of the Charpy upper-shelf was experienced in a positive K1 gradient and with K1 = 300 MPam. Fracture-mechanics analysis of brittle fracture based on small-specimen toughness measurements was reasonably accurate. Flaw evaluation by procedures of the ASME Boiler and Pressure Vessel Code conservatively predicted vessel failure, which did not occur. No ductile tearing occurred after each crack arrest, although some stable tearing had been predicted on the basis of tearing resistance data.  相似文献   
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Atomic‐layer‐deposited aluminium oxide (Al2O3) is applied as rear‐surface‐passivating dielectric layer to passivated emitter and rear cell (PERC)‐type crystalline silicon (c‐Si) solar cells. The excellent passivation of low‐resistivity p‐type silicon by the negative‐charge‐dielectric Al2O3 is confirmed on the device level by an independently confirmed energy conversion efficiency of 20·6%. The best results are obtained for a stack consisting of a 30 nm Al2O3 film covered by a 200 nm plasma‐enhanced‐chemical‐vapour‐deposited silicon oxide (SiOx) layer, resulting in a rear surface recombination velocity (SRV) of 70 cm/s. Comparable results are obtained for a 130 nm single‐layer of Al2O3, resulting in a rear SRV of 90 cm/s. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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PURPOSE: To report a case of corneal ulcer associated with deposits of norfloxacin. METHOD: Case report. A 40-year-old man with right trigeminal and facial nerve palsies and decreased tear secretion developed a corneal ulcer with white deposits in the right eye. The deposits were removed and analyzed by high-performance liquid chromatography. RESULTS: High-performance liquid chromatography results disclosed that the deposits on the corneal surface had the same retention time as norfloxacin. The patient discontinued norfloxacin ophthalmic solution and recovered successfully. CONCLUSION: Clinicians should be aware that frequent applications of topical norfloxacin in patients with decreased tear secretion may result in deposition of the drug on the cornea.  相似文献   
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The authors retrospectively evaluated the etiology and clinical findings of patients with first manifestations of psychotic symptoms after the age of 65. Nearly 10% of over 1,700 consecutive geriatric patients admitted to an acute inpatient psychogeriatric unit had late-life onset psychotic symptoms. About three-fourths of these were women, usually in their seventies. Dementia of the Alzheimer's type was the most common cause of psychosis arising in late life, followed by major depression, medical/toxic causes, delirium, bipolar disorder, delusional disorder, schizophrenia, and schizoaffective disorder. Clinical manifestations consisted mostly of delusions and hallucinations.  相似文献   
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A hemispheric asymmetry in the functional activation of the human motor cortex during contralateral (C) and ipsilateral (I) finger movements, especially in right-handed subjects, was documented with nuclear magnetic resonance imaging at high field strength (4 tesla). Whereas the right motor cortex was activated mostly during contralateral finger movements in both right-handed (C/I mean area of activation = 36.8) and left-handed (C/I = 29.9) subjects, the left motor cortex was activated substantially during ipsilateral movements in left-handed subjects (C/I = 5.4) and even more so in right-handed subjects (C/I = 1.3).  相似文献   
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Chickens have only two T cell receptor variable beta gene families: V beta 1 and V beta 2 (1). In our previous work we found that IgA production was almost completely suppressed in chickens depleted of V beta 1+ alpha beta T cells by treatment with a TCR V beta 1-specific monoclonal antibody (2), while IgM and IgG production was not affected. Our present results indicate that, in vitro, both V beta 1+ and V beta 2+ chicken cecal tonsil T cells provide help for the differentiation of cecal tonsil IgA B cells, suggesting that the failure of V beta 1+ T cell-depleted chickens to produce IgA is not caused by the inability of V beta 2+ T cells to provide help for IgA production by B cells, but rather by the scarcity of these T cells in mucosal tissues (3), where most IgA responses are induced (4).  相似文献   
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