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341.
Syllable frequency has been shown to facilitate production in some languages but has yielded inconsistent results in English and has never been examined in older adults. Tip-of-the-tongue (TOT) states represent a unique type of production failure where the phonology of a word is unable to be retrieved, suggesting that the frequency of phonological forms, like syllables, may influence the occurrence of TOT states. In the current study, we investigated the role of first-syllable frequency on TOT incidence and resolution in young (18–26 years of age), young-old (60–74 years of age), and old-old (75–89 years of age) adults. Data from 3 published studies were compiled, where TOTs were elicited by presenting definition-like questions and asking participants to respond with “Know,” “Don't Know,” or “TOT.” Young-old and old-old adults, but not young adults, experienced more TOTs for words beginning with low-frequency first syllables relative to high-frequency first syllables. Furthermore, age differences in TOT incidence occurred only for words with low-frequency first syllables. In contrast, when a prime word with the same first syllable as the target was presented during TOT states, all age groups resolved more TOTs for words beginning with low-frequency syllables. These findings support speech production models that allow for bidirectional activation between conceptual, lexical, and phonological forms of words. Furthermore, the age-specific effects of syllable frequency provide insight into the progression of age-linked changes to phonological processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
342.
The authors hypothesized that experienced and imagined intergenerational contact should improve older people's math test performance under stereotype threat. In Experiment 1 (N = 51, mean age = 69 years), positive prior contact with grandchildren eliminated stereotype threat, which was mediated partially by reduced test-related anxiety. In Experiment 2 (N = 84, mean age = 72 years), the effect of threat on performance was significantly improved when participants merely imagined intergenerational contact, a situation again mediated by reduced anxiety. Previous research established that intergroup contact improves intergroup attitudes. The findings show that intergroup (intergenerational) contact also provides a defense against stereotype threat. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
343.
Higher cigarette prices influence cigarette purchase patterns   总被引:2,自引:0,他引:2  
Objective: To examine cigarette purchasing patterns of current smokers and to determine the effects of cigarette price on use of cheaper sources, discount/generic cigarettes, and coupons.

Background: Higher cigarette prices result in decreased cigarette consumption, but price sensitive smokers may seek lower priced or tax-free cigarette sources, especially if they are readily available. This price avoidance behaviour costs states excise tax money and dampens the health impact of higher cigarette prices.

Methods: Telephone survey data from 3602 US smokers who were originally in the COMMIT (community intervention trial for smoking cessation) study were analysed to assess cigarette purchase patterns, use of discount/generic cigarettes, and use of coupons.

Results: 59% reported engaging in a high price avoidance strategy, including 34% who regularly purchase from a low or untaxed venue, 28% who smoke a discount/generic cigarette brand, and 18% who report using cigarette coupons more frequently that they did five years ago. The report of engaging in a price avoidance strategy was associated with living within 40 miles of a state or Indian reservation with lower cigarette excise taxes, higher average cigarette consumption, white, non-Hispanic race/ethnicity, and female sex.

Conclusion: Data from this study indicate that most smokers are price sensitive and seek out measures to purchase less expensive cigarettes, which may decrease future cessation efforts.

  相似文献   
344.
Monitoring ongoing processes of illness to detect sudden changes is an important aspect of practical epidemiology and medicine more generally. Most commonly, the monitoring has been restricted to a unidimensional stream of data over time. In such situations, analytic results from the industrial process monitoring have suggested optimal approaches to monitor the data streams. Data streams including spatial location as well as temporal sequence are becoming available. Monitoring methods that incorporate spatial data may prove superior to those that ignore it. However, analytically, optimal methods for spatial surveillance data may not exist. In the present article, we introduce and discuss evaluation metrics that can be used to compare the performance of statistical methods of surveillance. Our general approach is to generalize receiver operating characteristic (ROC) curves to incorporate the time of detection in addition to the usual test characteristics of sensitivity and specificity. In addition to weighting ordinary ROC curves by two measures of timeliness, we describe three three-dimensional generalizations of ROC curves that result in timeliness-ROC surfaces. Working in the context of surveillance of cases of disease to detect a sudden outbreak, we demonstrate these in an artificial example and in a previously described simulation context and show how the metrics differ. We also discuss the differences and under which circumstances one might prefer a given method.  相似文献   
345.
346.
Inhibition of return refers to a bias against returning attention to a location that has been recently attended. Experiments are reported that examined inhibition of return to multiple exogenously cued spatial locations. When 2 peripheral locations were cued in succession, inhibition was found for only the 1 most recently cued location. In addition, more inhibition occurred at the location of the most recent cue if the earlier cue had also been presented there, as compared with an earlier cue at a different location. Thus, the magnitude of the inhibition for a location appears to depend on the effectiveness of the attentional cue to that location. Other results suggest that candidate locations for inhibition are displaced by subsequent cues—they do not simply decay. The results provide an initial framework within which to study inhibition of return to multiple spatial locations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
347.
The longest part of the molding cycle during SMC compression molding is the curing stage. Thus it is extremely important to be able to predict its duration to estimate the cost of manufacturing a new part. During an SMC molding cycle, the mold surface temperature drops suddenly when it contacts the cold charge. The surface temperature then gradually recovers as heat is conducted from the interior of the mold and the resin releases heat during curing. In general, this exchange of heat remains locally unbalanced, causing a gradual decrease in the local surface temperature. To avoid blistering, the cure time must be increased with consecutive moldings until a steady state value is achieved (tcss). In this paper, we present a series of charts that can be used to estimate the steady state cure time for new parts. These values can then be used to estimate the manufacturing cost.  相似文献   
348.
The swept volume problem is practical, difficult and interesting enough to have received a great deal of attention over the years, and the literature contains much discussion of methods for computing swept volumes in many situations. The method presented here permits an arbitrary polyhedral object (given in a typical boundary representation) to be swept through an arbitrary trajectory. A polyhedral approximation to the volume swept by this moving object is computed and output in a typical boundary representation. A number of examples are presented demonstrating the practicality of this method. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
349.
One of the fastest‐growing applications of SMC compression molding is the manufacture of truck body panels. Because of their large size, the molding forces required are substantial and have a major influence on the molding cycle. Also, as SMC moves towards parts requiring higher strength, the fiber length and percentage by weight of fibers must increase. This will also contribute to larger molding forces. In this paper, a procedure is presented to evaluate the SMC rheological parameters needed to predict molding forces. In addition, the effect of SMC composition on the molding forces is investigated. In particular, we evaluate the effect of reinforcement type (glass versus carbon) and level, filler level and thickener level. It was found that the factors most affecting molding forces are the reinforcement length and level; and the filler level. In addition, it was discovered that for SMC thickened with magnesium oxide, the level of thickener does not affect the molding force.  相似文献   
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