967 research outputs found

    Teaching and learning about controversial science issues

    Get PDF
    The overarching Nature of Science (NoS) strand in our revised science curriculum presents teachers of science with a number of challenges. One of them is the ‘Participating and Contributing’ achievement aim with its focus on controversial science issues (CSI). This article reports on a new classroom model for exploring controversial science issues with students that was trialled in New Zealand science classrooms, writes Dr. Kathy Saunders, the University of Waikato

    Examining the concordance of retinal ganglion cell counts generated using measures of structure and function

    Get PDF
    PURPOSE: There are several indirect methods used to estimate retinal ganglion cell (RGC) count in an individual eye, but there is limited information as to the agreement between these methods. In this work, RGC receptive field (RGC‐RF) count underlying a spot stimulus (0.43°, Goldmann III) was calculated and compared using three different methods. METHODS: RGC‐RF count was calculated at a retinal eccentricity of 2.32 mm for 44 healthy adult participants (aged 18–58 years, refractive error −9.75 DS to +1.75 DS) using: (i) functional measures of achromatic peripheral grating resolution acuity (PGRA), (ii) structural measures of RGC‐layer thickness (OCT‐model, based on the method outlined by Raza and Hood) and (iii) scaling published histology density data to simulate a global expansion in myopia (Histology‐Balloon). RESULTS: Whilst average RGC‐RF counts from the OCT‐model (median 105.3, IQR 99.6–111.0) and the Histology‐Balloon model (median 107.5, IQR 97.7–114.6) were similar, PGRA estimates were approximately 65% lower (median 37.7, IQR 33.8–46.0). However, there was poor agreement between all three methods (Bland–Altman 95% limits of agreement; PGRA/OCT: 55.4; PGRA/Histology‐Balloon 59.3; OCT/Histology‐Balloon: 52.4). High intersubject variability in RGC‐RF count was evident using all three methods. CONCLUSIONS: The lower PGRA RGC‐RF counts may be the result of targeting only a specific subset of functional RGCs, as opposed to the coarser approach of the OCT‐model and Histology‐Balloon, which include all RGCs, and also likely displaced amacrine cells. In the absence of a ‘ground truth’, direct measure of RGC‐RF count, it is not possible to determine which method is most accurate, and each has limitations. However, what is clear is the poor agreement found between the methods prevents direct comparison of RGC‐RF counts between studies utilising different methodologies and highlights the need to utilise the same method in longitudinal work

    Reading Instruction for Children who use AAC: Considerations in the Pursuit of Generalizable Results

    Get PDF
    Our purpose was to review evidence-based literacy instruction for children with severe speech impairment (SSI) who communicate with AAC. This review focuses on three issues important to researchers in this area: participant heterogeneity, assessment and instruction, and research design. We found 8 articles that reported attempts to teach phonological awareness and individual-word reading to a total of 26 children with SSI who used AAC. We evaluated these studies based on reporting of participant characteristics, assessment and instruction modifications, and the strength of research designs. We conclude by highlighting the need for standard assessments that can be used across studies, discussing strategies for facilitating metaanalyses, and suggesting the creation of an online database for researchers to share results on literacy instruction for this population

    Comparison of amblyopia in schoolchildren in Ireland and Northern Ireland:a population-based observational cross-sectional analysis of a treatable childhood visual deficit

    Get PDF
    Objectives This study reports the prevalence of persistent amblyopia (post-traditional treatment age) in schoolchildren in the Republic of Ireland (henceforth Ireland) and Northern Ireland (NI), UK; populations with broadly similar refractive and genetic profiles but different eye-care systems. Design This is a population-based observational study of amblyopia and refractive error. Setting Recruitment and testing in primary and postprimary schools in Ireland and NI. Participants Two groups identified through random cluster sampling to represent the underlying population; Ireland 898 participants (12–13 years old) and NI 723 participants (295 aged 9–10 years old, 428 aged 15– 16 years old). Main outcome measures Monocular logMAR visual acuity (presenting and pinhole), refractive error (cycloplegic autorefraction), ocular alignment (cover test) and history of previous eye care. These metrics were used to determine prevalence and type of amblyopia and treatment histories. Results Children examined in NI between 2009 and 2011 had a significantly lower amblyopia prevalence than children examined in Ireland between 2016 and 2018 (two-sample test of proportions,
    corecore