Visual stimuli in intervention approaches for pre-schoolers diagnosed with phonological delay

Purpose: There is a need to develop letter knowledge assessment tools to characterise the letter knowledge in Portuguese pre-schoolers and to compare it with pre-schoolers from other countries, but there are no tools for this purpose in Portugal. The aim of this paper is to describe the development and validation procedures of the Prova de Avaliac¸ao de Compet ~ ^encias de Pr e-Literacia (PACPL), which assesses letter knowledge. Method: This study includes data that has been gathered in two phases: pilot and main study. In the pilot study, an expert panel of six speech and language pathologists analysed the instrument. Children (n ¼ 216) aged 5;0–7;11 participated in the main study that reports data related to the psychometric characteristics of the PACPL. Content validity, internal consistency, reliability and contributing factors to performance were examined statistically. Results: A modified Bland–Altman method revealed good agreement amongst evaluators. The main study showed that the PACPL has a very good internal consistency and high inter-rater (96.2% of agreement and a Cohen’s k value of 0.92) and intra-rater (95.6% of agreement and a Cohen’s k value of 0.91) agreement. Construct validity of the PCAPL was also assured (Cronbach’s a of 0.982). Significant differences were found between age groups with children increasing their letter knowledge with age. In addition, they were better at identifying than at producing both letter names and letter sounds. Conclusions: The PACPL is a valid and reliable instrument to assess letter knowledge in Portuguese children.publishe

Study of Fermion Pair Production in e+e−e^{+}e^{-} Collisions at 130-183 GeV

The cross sections and forward-backward asymmetries of hadronic and leptonic events produced in e+e- collisions at centre-of-mass energies of 130-183 GeV are presented. Results for ee, mumu, tautau, qq, bb and cc production show no significant deviation from the Standard Model predictions. This enable constraints to be set upon physics beyond the Standard Model such as four-fermion contact interactions, leptoquarks, Z' bosons and R-parity violating squarks and sneutrinos. Limits on the energy scale Lambda of eeff contact interactions are typically in the range from 2-10 TeV. Limits on R-parity violating sneutrinos reach masses of a few hundred GeV for large values of their Yukawa couplings