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91.
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The semantic interference effect in the picture–word interference task is interpreted as an index of lexical competition in prominent speech production models. Janssen, Schirm, Mahon, and Caramazza (2008) challenged this interpretation on the basis of experiments with a novel version of this task, which introduced a task-switching component. Participants either named the picture or read the word, depending on the word's color. Janssen et al. reported semantic interference in picture naming, regardless of whether the word appeared simultaneously with the picture (immediate naming) or 1,000 ms after the picture (delayed naming). Because picture name retrieval is completed in less than 1,000 ms, the finding in delayed naming was taken as evidence against the lexical competition account. In 3 sets of experiments conducted in German and English, we tested for semantic effects in Janssen et al.'s task-switching version and in the standard picture–word interference task. Using identical materials, we obtained sizeable interference effects in the standard task (Experiments 2, 4, and 6) but no effects in the task-switching version (Experiments 1, 3, and 5). When the word reading trials of the task-switching version were replaced with no-go trials (Experiment 7), semantic interference reemerged in immediate naming but was still absent in delayed naming. The experiments question the reliability of Janssen et al.'s critical finding and suggest that theoretical inferences about the origin of semantic effects in the standard picture–word interference task based on results from the task-switching version used by Janssen et al. are difficult to draw. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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OBJECTIVE: To determine whether application of topical aqueous lidocaine to a laceration attenuates the pain from the subsequent lidocaine injection in children. DESIGN: Prospective, double-blind study. SETTING: A large, urban, tertiary care children's hospital emergency department. PATIENTS: A convenience sample of 100 children, five to 16 years of age, presenting with simple lacerations over a six-month period. INTERVENTIONS: An unlabelled 3-ml solution of either 1% lidocaine or placebo (saline) was used to soak a Telfa pad (Kendall, Mansfield, MA) and then placed onto the laceration for 10 minutes. The wound was then injected with 1% lidocaine, irrigated, and sutured per standard emergency department protocol. Independent pain response was elicited from the patient and parent four times: before any intervention, after the soak, after the injection, and at the end of the procedure. Blood pressure and heart rates were recorded at the same intervals. RESULTS: Four patients were excluded. Of the 96 remaining patients, 46 received the placebo and 50 received lidocaine. Age, sex, race, and laceration length and location were similar between groups. Physiologic parameters did not differ between groups. For all four pain ratings, the independent variables of age, sex, race, and laceration length or location did not differ between groups. Topical lidocaine was ineffective in relieving pain from the injection. When groups were combined, a significant negative correlation was noted for age versus injection pain (P = .035), with older children reporting less pain from injection than younger children. CONCLUSION: For children, soaking a simple laceration with 1% lidocaine does not decrease pain from the subsequent lidocaine injection.  相似文献   
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A resonant time-of-flight measurement system has been put into operation at the ATLAS facility for the determination of the energy of heavy ion beams. The system provides continuous, nondestructive monitoring of the beam energy. The system provides relative energy determination with a precision of . Absolute energy is determined to an accuracy of 10−3. A variety of beam tests have been performed to study the properties of the system.  相似文献   
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Well-established rapid mixing techniques such as stopped-flow have been used to push the dead time for kinetic experiments down to a few milliseconds. However, very fast reactions are difficult to resolve below this limit. We now outline an approach that provides access to ultrafast kinetics but does not rely on active mixing at all. Here, the reagents are compartmentalized into water-in-oil emulsion microdroplets (diameter ~50 μm) that are statically arrayed in pairs, resting side-by-side in a well feature of a poly(dimethylsiloxane) (PDMS) device. A reaction between the contents of two droplets arrayed in such a holding trap is initiated by droplet fusion that is brought about by electrocoalescence and known to occur on a time scale of about 100 μs. A reaction between the reactants (Fe(3+) and SCN(-)) is monitored by image analysis measuring the product formation in the newly merged drop in both space and time, by use of a fast camera. A comparison of the concentration field of the reaction product with the output of a reaction-diffusion system of equations yields a rate constant k ~ 3 × 10(4) M(-3)·s(-1). Since reaction and diffusion are formally included in the mathematical model, measurements can proceed immediately after the drop fusion, removing the need to allow time for mixing. This approach is different from existing methodologies, for example, experiments in a conventional stopped-flow apparatus but also electrofusion of moving droplets where contents are mixed by chaotic advection before a reaction is monitored. Our analysis makes kinetics accessible that are several times faster than techniques that have to allow time for mixing.  相似文献   
96.
In this article we present an engineering approach for the integration of social group dynamics in the behavior modeling of multiagent systems. To this end, a toolbox was created that brings together several theories from the social sciences, each focusing on different aspects of group dynamics. Due to its modular approach, the toolbox can either be used as a central control component of an application or it can be employed temporarily to rapidly test the feasibility of the incorporated theories for a given application domain. This is exemplified by applying the toolbox to different applications.
Matthias Rehm (Corresponding author)Email:
Birgit EndrassEmail:
  相似文献   
97.
The 3D transient motion of a buoyancy-driven perfect gas in an enclosure is computed by a FORTRAN program (BF3D). A combustion model for eventual inclusion in this program is under development. BF3D changes slowly, has a long lifetime, and is run fairly infrequently. Typical runs have large storage and CPU requirements. BF3D runs on large supercomputers but the newer mini-supercomputers appear to be suitable also and may be advantageous for ease of access and usage. Programming workstations are convenient for development. Comparisons of BF3D on selected supercomputers, mini-supercomputers, scientific workstations and conventional mainframes are presented for the purpose of making partial benchmark data available to the computing public.  相似文献   
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In the first part of the study, the readiness of bartenders and waiters to serve alcoholic beverages to young teenagers was studied. The fieldwork was conducted in a random sample of bars and restaurants in Lausanne and in villages of the canton of Vaud, where 13-year-old and 15-year-old boys ordered either beer or pastis (an aniseed-flavoured aperitif). Results showed that alcoholic beverages were very accessible to 13-year-old and 15-year-old youths although the minimum legal age for purchasing and consuming beer is 16 years and for pastis is 18 years: 81% of the test orders were served. An analysis of interaction of patterns between servers and clients suggested that time necessary to refuse orders may play an important role in explaining this result. In the second part of the study, knowledge and attitudes of owners and managers of bars, restaurants and different kinds of commercial outlet were studied in a telephone interview survey about the minimum legal age for purchasing and consuming alcoholic beverages. Only 17% of the respondents knew the correct minimum legal ages for purchasing and consuming alcoholic beverages.  相似文献   
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