Focussing on form in the classroom

Current theories of second language acquisition emphasise the importance of learners' attending consciously to form. Similarly, current discussions of communicative language pedagogy stress the need for classroom language learners to focus on form as well as meaning. The study reported in this article is intended to contribute to both theory and practice. It examines the different ways in which teachers and students achieve a ‘focus-on-form' (i.e. attend to linguistic form in the context of activity that is primarily message-oriented). Based on an analysis of 12 hours of teaching English in a private language school, a coding system is developed to account for the general characteristics of ‘focus-on-form episodes' (FFEs). The system is then used to provide an account of focus-on-form in the classrooms studied, revealing that nearly half of the total FFEs were proactive rather than reactive and that more than half involved negotiating form rather than negotiating meaning (i.e. they were not triggered by any communicative problem). The paper concludes with proposals for future research. Key words: communicative pedagogy, focus-on-form, uptake [Jnl for Language Teaching Vol.37(2) 2003: 149-163

Experimental validation of image contrast correlation between ultra-small-angle X-ray scattering and grating-based dark-field imaging using a laser-driven compact X-ray source: Experimentelle Verifizierung des Zusammenhangs zwischen Röntgen-Kleinwinkelstreuung und gitter-basierter Röntgen-Dunkelfeldbildgebung unter Verwendung eines laser-getriebenen Kompaktsynchrotrons

X-ray phase and dark-field contrast have recently been the source of much attention in the field of X-ray imaging, as they both contribute new imaging signals based on physical principles that differ from conventional X-ray imaging. With a so-called Talbot grating interferometer, both phase-contrast and dark-field images are obtained simultaneously with the conventional attenuation-based X-ray image, providing three complementary image modalities that are intrinsically registered. Whereas the physical contrast mechanisms behind attenuation and phase contrast are well understood, a formalism to describe the dark-field signal is still in progress. In this article, we report on correlative experimental results obtained with a grating interferometer and with small-angle X-ray scattering. Furthermore, we use a proposed model to quantitatively describe the results, which could be of great importance for future clinical and biomedical applications of grating-based X-ray imagin

Diagnosing and mapping pulmonary emphysema on X-ray projection images

To assess whether grating-based X-ray dark-field imaging can increase the sensitivity of X-ray projection images in the diagnosis of pulmonary emphysema and allow for a more accurate assessment of emphysema distribution. Lungs from three mice with pulmonary emphysema and three healthy mice were imaged ex vivo using a laser-driven compact synchrotron X-ray source. Median signal intensities of transmission (T), dark-field (V) and a combined parameter (normalized scatter) were compared between emphysema and control group. To determine the diagnostic value of each parameter in differentiating between healthy and emphysematous lung tissue, a receiver-operating-characteristic (ROC) curve analysis was performed both on a per-pixel and a per-individual basis. Parametric maps of emphysema distribution were generated using transmission, dark-field and normalized scatter signal and correlated with histopathology. Transmission values relative to water were higher for emphysematous lungs than for control lungs (1.11 vs. 1.06, p<0.001). There was no difference in median dark-field signal intensities between both groups (0.66 vs. 0.66). Median normalized scatter was significantly lower in the emphysematous lungs compared to controls (4.9 vs. 10.8, p<0.001), and was the best parameter for differentiation of healthy vs. emphysematous lung tissue. In a per-pixel analysis, the area under the ROC curve (AUC) for the normalized scatter value was significantly higher than for transmission (0.86 vs. 0.78, p<0.001) and dark-field value (0.86 vs. 0.52, p<0.001) alone. Normalized scatter showed very high sensitivity for a wide range of specificity values (94% sensitivity at 75% specificity). Using the normalized scatter signal to display the regional distribution of emphysema provides color-coded parametric maps, which show the best correlation with histopathology. In a murine model, the complementary information provided by X-ray transmission and dark-field images adds incremental diagnostic value in detecting pulmonary emphysema and visualizing its regional distribution as compared to conventional X-ray projections

Advanced EFL learners' beliefs about language learning and teaching: a comparison between grammar, pronunciation, and vocabulary

This paper reports on the results of a study exploring learners’ beliefs on the learning and teaching of English grammar, pronunciation and vocabulary at tertiary level. While the importance of learners’ beliefs on the acquisition process is generally recognized, few studies have focussed on and compared learners’ views on different components of the language system. A questionnaire containing semantic scale and Likert scale items probing learners’ views on grammar, pronunciation and vocabulary was designed and completed by 117 native speakers of Dutch in Flanders, who were studying English at university. The analysis of the responses revealed that (i) vocabulary was considered to be different from grammar and pronunciation, both in the extent to which an incorrect use could lead to communication breakdown and with respect to the learners’ language learning strategies, (ii) learners believed in the feasibility of achieving a native-like proficiency in all three components, and (iii) in-class grammar, pronunciation and vocabulary exercises were considered to be useful, even at tertiary level. The results are discussed in light of pedagogical approaches to language teaching

Timed and untimed grammaticality judgments measure distinct types of knowledge: Evidence from eye-movement patterns

Copyright © 2015 Cambridge University Press. Grammaticality judgment tests (GJTs) have been used to elicit data reflecting second language (L2) speakers' knowledge of L2 grammar. However, the exact constructs measured by GJTs, whether primarily implicit or explicit knowledge, are disputed and have been argued to differ depending on test-related variables (i.e., time pressure and item grammaticality). Using eye-tracking, this study replicates the GJT results in R. Ellis (2005). Twenty native and 40 nonnative English speakers judged sentences with and without time pressure. Analyses revealed that time pressure suppressed regressions (right-to-left eye movements) in nonnative speakers only. Conversely, both groups regressed more on untimed, grammatical items. These findings suggest that timed and untimed GJTs measure different constructs, which could correspond to implicit and explicit knowledge, respectively. In particular, they point to a difference in the levels of automat ic and controlled processing involved in responding to the timed and untimed tests. Furthermore, untimed grammatical items may induce GJT-specific task effects

Hard X-ray phase-contrast imaging with the Compact Light Source based on inverse Compton X-rays

First X-ray phase-contrast imaging results recorded at the Compact Light Source, a laboratory-based inverse Compton X-ray source, are reported

Multimodal hard X-ray imaging of a mammography phantom at a compact synchrotron light source

The Compact Light Source is a miniature synchrotron producing X-rays at the interaction point of a counter-propagating laser pulse and electron bunch through the process of inverse Compton scattering. The small transverse size of the luminous region yields a highly coherent beam with an angular divergence of a few milliradians. The intrinsic monochromaticity and coherence of the produced X-rays can be exploited in high-sensitivity differential phase-contrast imaging with a grating-based interferometer. Here, the first multimodal X-ray imaging experiments at the Compact Light Source at a clinically compatible X-ray energy of 21 keV are reported. Dose-compatible measurements of a mammography phantom clearly demonstrate an increase in contrast attainable through differential phase and dark-field imaging over conventional attenuation-based projections

The measurement of implicit and explicit knowledge

© 2018, © 2018 Association for Language Learning. This article presents a review of research that has investigated ways of measuring implicit and explicit knowledge of a second language (L2), focusing on grammar. It begins by defining implicit and explicit knowledge in terms of a distinguishing set of criteria. Two ways of investigating implicit knowledge are discussed–through experimental studies of implicit learning and by means of factor-analytic studies. This provides the basis for a taxonomy of tests designed to provide separate measures of the two types of knowledge. Proposals for oral production tests, comprehension tests, judgements tests, tests of metalinguistic knowledge and tests derived from psycholinguistic research are examined and critiqued. The article concludes by suggesting there is a need for tests of L2 pragmatic knowledge to complement those available for grammar and offers a number of suggestions for the design of such tests