1,787 research outputs found

    A covariant constituent-quark formalism for mesons

    Full text link
    Using the framework of the Covariant Spectator Theory (CST) [1] we are developing a covariant model formulated in Minkowski space to study mesonic structure and spectra. Treating mesons as effective qqˉq\bar{q} states, we focused in [2] on the nonrelativistic bound-state problem in momentum space with a linear confining potential. Although integrable, this kernel has singularities which are difficult to handle numerically. In [2] we reformulate it into a form in which all singularities are explicitely removed. The resulting equations are then easier to solve and yield accurate and stable solutions. In the present work, the same method is applied to the relativistic case, improving upon the results of the one-channel spectator equation (1CSE) given in [3].Comment: 6 pages, 5 figures, Presented at EEF70, Workshop on Unquenched Hadron Spectroscopy: Non-Perturbative Models and Methods of QCD vs. Experimen

    The Efficacy of an Explicit Intervention Approach to Improve Past Tense Marking for Early School-Age Children With Developmental Language Disorder

    Get PDF
    Purpose The aim of the study was to evaluate the efficacy of a theoretically motivated explicit intervention approach to improve regular past tense marking for early school-age children with developmental language disorder (DLD). Method Twenty-one children with DLD (ages 5;9–6;9 [years;months]) were included in a crossover randomized controlled trial (intervention, n = 10; waiting control, n = 11). Intervention included once-weekly sessions over 10 weeks using the SHAPE CODING system, in combination with a systematic cueing hierarchy to teach past tense marking. Once the first group completed intervention, the waiting control group crossed over to the intervention condition. The primary outcome was criterion-referenced measures of past tense marking with standardized measures of expressive and receptive grammar as the secondary outcome. Ancillary analyses on extension and behavioral control measures of morphosyntax were also conducted. Results There was a significant Time × Group interaction (p < .001) with a significant difference in pre–post intervention improvement in favor of the intervention group (p < .001, d = 3.03). Further analysis once both groups had received the intervention revealed no improvement for either group on past tense production during the 5-week pre-intervention period, significant improvement pre–post intervention (p < .001, d = 1.22), with gains maintained for 5 weeks postintervention. No significant differences were found on pre- to postintervention standardized measures of grammar, or on extension or control measures. Conclusions The efficacy of the theoretically motivated explicit grammar intervention was demonstrated. Results contribute to the evidence base supporting this intervention to improve past tense production in early school-age children with DLD, suggesting it is a viable option for clinicians to select when treating morphosyntactic difficulties for this population

    Explicit Grammar Intervention in Young School-Aged Children With Developmental Language Disorder: An Efficacy Study Using Single-Case Experimental Design

    Get PDF
    PURPOSE: This study evaluated the efficacy of an explicit, combined metalinguistic training and grammar facilitation intervention aimed at improving regular past tense marking for nine children aged 5;10–6;8 (years;months) with developmental language disorder. METHOD: This study used an ABA across-participant multiple-baseline single-case experimental design. Participants were seen one-on-one twice a week for 20- to 30-min sessions for 10 weeks and received explicit grammar intervention combining metalinguistic training using the SHAPE CODING system with grammar facilitation techniques (a systematic cueing hierarchy). In each session, 50 trials to produce the target form were completed, resulting in a total of 1,000 trials over 20 individual therapy sessions. Repeated measures of morphosyntax were collected using probes, including trained past tense verbs, untrained past tense verbs, third-person singular verbs as an extension probe, and possessive 's as a control probe. Probing contexts included expressive morphosyntax and grammaticality judgment. Outcome measures also included pre–poststandard measures of expressive and receptive grammar. RESULTS: Analyses of repeated measures demonstrated significant improvement in past tense production on trained verbs (eight of nine children) and untrained verbs (seven of nine children), indicating efficacy of the treatment. These gains were maintained for 5 weeks. The majority of children made significant improvement on standardized measures of expressive grammar (eight of nine children). Only five of nine children improved on grammaticality judgment or receptive measures. CONCLUSIONS: Results continue to support the efficacy of explicit grammar interventions to improve past tense marking in early school-aged children. Future research should aim to evaluate the efficacy of similar interventions with group comparison studies and determine whether explicit grammar interventions can improve other aspects of grammatical difficulty for early school-aged children with developmental language disorder

    Mesofauna do solo em floresta secundária e em cultivos do cupuaçuzeiro e do guaranazeiro no município de Belém-Pará.

    Get PDF
    bitstream/item/59302/1/CPATU-ComTec77.pd
    • …
    corecore