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A classification of models of visual word recognition is presented that facilitates formal comparisons between models of different formats. In light of the theoretical contributions to this special section, sets of criteria for the evaluation of models and strategies for model construction are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
Evaluated the contributions of strategic and data-driven factors to skilled performance by manipulating the predictability of the class of stimuli used in a memory search task. In Exp 1, when consistent mapping (CM) and varied mapping (VM) conditions were blocked, large performance differences were observed; however, when CM and VM trials were mixed, performance differences were reduced. In Exp 2, mixed training led to a less skilled performance than blocked training. Moreover, transfer conditions revealed a critical interval for learning to adopt and deploy differential response strategies. Exp 3 demonstrated that the differential response strategies were not stimulus specific. Analysis suggests that skilled performance can be conceptualized as an interaction between enhanced evidence accumulation and strategic setting of response criteria. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study evaluated the effectiveness of four posttreatment programs designed to enhance the long-term maintenance of weight loss. Mildly and moderately obese adults (N?=?123) were randomly assigned to one of the following five conditions: (a) behavior therapy only; (b) behavior therapy plus a posttreatment therapist-contact maintenance program; (c) behavior therapy plus posttreatment therapist contact plus a social influence maintenance program; (d) behavior therapy plus posttreatment therapist contact plus an aerobic exercise maintenance program; or (e) behavior therapy plus posttreatment therapist contact plus both the aerobic exercise and social influence maintenance programs. All posttreatment programs were conducted in 26 biweekly sessions during the year following behavioral treatment for obesity. At an 18-month follow-up evaluation, all four conditions that combined behavior therapy with a posttreatment maintenance program yielded significantly greater long-term weight losses than behavior therapy alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
In several chronic diseases, lesions are more severe in LEW rats than in F344 rats. To determine whether or not acute viral diseases also are more severe in LEW rats than in F344 rats, we inoculated 6-7-week-old LEW and F344 rats with 10(7.2) cell culture infective units of sialodacryoadenitis virus or 10(4.7) infective units of Sendai virus. Twenty-four rats of each strain were given each virus. Lesions in nasal passages, tracheas, intrapulmonary airways, and pulmonary alveoli in 6 or 12 rats inoculated with each virus were assessed by scoring 5, 10, and 14 days after inoculation. Both viruses caused typical patchy necrotizing rhinitis, tracheitis, bronchitis, and bronchiolitis, with multifocal pneumonitis, in rats of both strains. Mean lesion indices for LEW rats given sialodacryoadenitis virus were significantly different from those for F344 rats for nasal passages on days 10 (0.999 vs. 0.680) and 14 (0.736 vs. 0.278), bronchi on day 5 (0.479 vs. 0.361), and alveoli on day 5 (0.677 vs. 0.275). Lesion indices for LEW rats given Sendai virus were significantly different from those for F344 rats for nasal passages on days 10 (1.000 vs. 0.611) and 14 (0.778 vs. 0.583); trachea on day 10 (0.625 vs. 0.028); bronchi on days 5 (0.476 vs. 0.331), 10 (0.123 vs. 0.013), and 14 (0.038 vs. 0); and alveoli on days 5 (0.413 vs. 0.114) and 10 (0.185 vs. 0.020). Thus, at the tested doses, both viruses caused more severe respiratory tract lesions in LEW rats than in F344 rats.  相似文献   
68.
Constructing inferences during narrative text comprehension.   总被引:1,自引:0,他引:1  
Describes a constructionist theory that accounts for the knowledge-based inferences that are constructed when readers comprehend narrative text. Readers potentially generate a rich variety of inferences when they construct a referential situation model of what the text is about. The proposed constructionist theory specifies that some, but not all, of this information is constructed under most conditions of comprehension. The distinctive assumptions of the constructionist theory embrace a principle of search (or effort) after meaning. According to this principle, readers attempt to construct a meaning representation that addresses the reader's goals, that is coherent at both local and global levels, and that explains why actions, events, and states are mentioned in the text. This study reviews empirical evidence that addresses this theory and contrasts it with alternative theoretical frameworks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
A dual read-out model of context effects in letter perception is described that predicts forced-choice accuracy in the Reicher paradigm and its relation to word reportability. It is hypothesized that a correct choice to a letter in a word context is made when either the correct letter representation or a word representation containing the correct letter in the correct position reaches a response threshold (a criterion level of activation). This hypothesis was implemented using the basic architecture of the interactive activation model (J. L. McClelland & D. E. Rumelhart, 1981) in its semistochastic variant (A. M. Jacobs & J. Grainger, 1992). The model successfully captures the data of J. C. Johnston (1978), otherwise thought to be critically damaging for this type of model, and accurately predicts performance in a series of new experiments using the Reicher paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
Steam Surface Pasteurization of Beef Frankfurters   总被引:3,自引:0,他引:3  
Meat and poultry products are sources of foodborne bacterial contamination. We used flash steam heating followed by evaporative cooling to quickly reduce bacterial contamination on the surface of beef frankfurters without degrading appearance. The rate of heat transfer was studied by measuring surface temperature in a pressure chamber during steam heating. Quality changes were determined by measuring color and weight as functions of steam temperature and treatment time. Efficacy of the process was verified by microbiological experiments using L. innocua. Treatment times of 30–40 set at 115–136°C gave a 4 log reduction in bacterial counts on the surface without severely affecting color or weight. After long-term storage at 6°C and at 19°C, levels of bacteria on inoculated frankfurters remained reduced and there was no difference between treated and untreated products in color or weight.  相似文献   
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