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971.
Smith Stephen D.; Most Steven B.; Newsome Leslie A.; Zald David H. 《Canadian Metallurgical Quarterly》2006,6(3):523
The current study examines whether aversively conditioned stimuli can modulate attention to such a degree that they impair the perception of subsequently presented nonemotional targets. In the initial phase of this study, participants viewed 3 categories of photographs, 1 of which was paired with an aversive noise. Following conditioning, participants searched for a target embedded within a series of 17 rapidly presented images on each trial. Critically, a conditioned or unconditioned item from the initial phase appeared 200 ms or 800 ms before the target. At 200-ms lags but not 800-ms lags, the conditioned images impaired target detection relative to the other distractors. Thus, temporary visual deficits can be induced by otherwise neutral distractors whose aversive associations have only recently been learned. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
972.
973.
Tensile properties of two responsive hydrogels 总被引:1,自引:0,他引:1
Temperature-responsive hydrogels were prepared from N-vinyl caprolactam/ethylene glycol dimethacrylate (PVCL) or from hydroxypropylcellulose/divinyl sulfone (HPC). Both gels undergo reversible volume shrinkage between room temperature and 50 °C, and for both, the tensile stress–strain behavior in the collapsed state above the temperature-induced transition is qualitatively different from that at room temperature. At the higher temperature, PVCL gels become stiffer, more ductile, and more viscoelastic. HPC gels, on the other hand, have lower initial tangent moduli in the high-temperature state. Possible molecular mechanisms are suggested, and implications for the design of temperature-responsive actuators (‘artificial muscles’) from these materials are discussed. 相似文献
974.
J Leslie 《Canadian Metallurgical Quarterly》1996,139(16):388-391
Simulation of disease transmission in laying flocks infected with Salmonella enteritidis phage type 4 over a 48-week egg-production period indicated that the maximum weekly incidence risk could range from 0.05 to 0.28, and the maximum proportion of culture-positive birds could range from 0.20 to 0.77 of the flock, depending on the effective contact rate. If the egg contamination proportion were 0.08, contaminated egg production could vary from a weekly maximum of 0.42 per cent to 2.24 per cent depending on the effective contact rate, but the actual rate of contamination was more important in determining the numbers of infected eggs produced. The results from previous studies suggest that this proportion could range from 0.075 to 0.25. The model produced levels of infected and immune birds similar to those reported in the literature, suggesting effective contact rates of between 2 and 4.5. There is insufficient information on transmission cycles to validate the model, but it does provide a mechanism for consolidating research findings, reviewing areas for further research, and aiding more effective planning for disease control. 相似文献
975.
Recent studies have suggested that clot-bound thrombin plays an important role in thrombus growth. In this study, we examined the effects of recombinant human soluble thrombomodulin (rhsTM) on clot-induced coagulation. rhsTM enhanced the activation of protein C by clots, and attenuated clot-induced thrombin generation and fibrinopeptide A (FPA) production in a dose-dependent manner. The inhibitory effect of rhsTM was abolished by anti-protein C antibody. The inhibitory effect of rhsTM on clot-induced thrombin generation continued for over 60 min after the addition of the clot, while an active site-directed thrombin inhibitor, argatroban, produced a more transient inhibition. rhsTM also inhibited the regrowth of the clot in (125)I-fibrinogen-supplemented plasma. We also examined the effect of rhsTM by thromboelastography, rhsTM reduced the growth of the clot but had little effect on the time to begin clotting, while heparin and Fragmin (low molecular weight heparin) had effects opposite to those of rhsTM. These findings suggest that rhs-TM attenuates the growth of the clot by activating protein C and inhibiting further thrombin generation in the clot. 相似文献
976.
Honos-Webb Lara; Stiles William B.; Greenberg Leslie S. 《Canadian Metallurgical Quarterly》2003,50(2):189
This article reports the development of a marker-based method for rating assimilation in psychotherapy with a case study of a woman, Sarah, who was treated for depression with process-experiential psychotherapy. To increase the rigor of the qualitative case study methodology, independent judges rated passages--taken out of context and randomly ordered--from the qualitative analysis. The authors examined levels of training required to make quantitative judgments by comparing ratings from 4 graduate students and 4 undergraduate students. Pooled reliabilities of the 2 groups of caters were high (.90 and .84), and the estimated reliability of single graduate student raters was acceptable (.70). Consistent findings across a series of related case studies are reviewed to address the generalizability of the findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
977.
Forehand Rex; Steele Ric; Armistead Lisa; Morse Edward; Simon Patricia; Clark Leslie 《Canadian Metallurgical Quarterly》1998,66(3):513
The psychosocial adjustment of 87 inner-city African American children 6–11 years old whose mothers were HIV infected was compared with that of 149 children from a similar sociodemographic background whose mothers did not report being HIV infected. Children were not identified as being HIV infected. Mother reports, child reports, and standardized reading achievement scores were used to assess 4 domains of adjustment: externalizing problems, internalizing problems, cognitive competence, and prosocial competence. The results indicated that, on average, children from both groups had elevated levels of behavior problem scores and low reading achievement scores when compared with national averages. Relative to children whose mothers were not infected, those whose mothers were HIV infected were reported to have more difficulties in all domains of psychosocial adjustment. Potential family processes that may explain the findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
978.
Diemer Roberta A.; Lobell Leslie K.; Vivino Barbara L.; Hill Clara E. 《Canadian Metallurgical Quarterly》1996,43(1):99
Twenty-five distressed adult clients received 2 sessions each of dream and event interpretation using the Hill model during 12 sessions of successful therapy. No differences were found in depth, insight, and working alliance among dream interpretation, event interpretation, and unstructured sessions, suggesting that dream interpretation is as effective as other therapist strategies. Dream and event interpretation may be equally effective because both lead back to relevant waking concerns and past memories. Pretreatment measures of client psychological mindedness, openness, and insight were generally unrelated to each other, to evaluations of insight within sessions, to therapist evaluations of client insight, and to pre- and posttherapy changes in insight. Cognitive complexity of client dialogue was related to the process and outcome of dream interpretation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
979.
Leslie Rodriguez Robert T Magari 《Quality Assurance: Good Practice, Regulation, and Law》2005,11(2):63-73
Customer complaints data are usually expressed as counts for a period of time and are governed by a Poisson process. This process is stationary when the number of complaints is constant, while a change in these numbers would indicate a potential change in the product performance. In this paper we describe an approach for establishing the maximum tolerance level for the number of complaints received within a month. Tolerance level is based on a relatively stable period of time when the Poisson process is stationary. A change-point analysis is performed to the complaints data that exhibit large changes to partition the relatively stable period from the problematic period. Examples that illustrate this approach are provided. 相似文献
980.
T Leslie 《Canadian Metallurgical Quarterly》1997,58(7):341-342
This article explains how to perform a skin biopsy with details about instruments and equipment. The patient's consent should always be obtained for the procedure. The wound margins should be marked out along the skin crease lines. The specimen should always be sent for analysis. 相似文献