296 research outputs found

    Story patterns in oral narratives: a variationist critique of Labov and Waletzky's model of narrative schemas

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    Labov and Waletzky's (1967) influential six-schema model of personal narratives has often been considered to make claims regarding a 'universal' narrative structure (Hurst, 1990; Hymes, 1996). This study tests how far variations in personal narratives at a schematic level (that is, which schemas are present and how they combine to structure the narrated experience) correlate with aspects of an individual's culture. Oral narratives produced by members of the Greek Cypriot community in London are analysed, to provide data from an alternative group of informants to Labov and Waletzky's, while still using their model as the central framework for analysis. Frequent appearance in the data of an additional schema, 'post-evaluation', suggests that culture is a variable in relation to narrative structure, as are more specific individual and social factors including age and gender. Story topic is also shown to influence how narratives are structured, with different topics resulting in different structures and the general underlying theme of "Trouble" (Burke, 1945; Bruner, 1991; Bruner, 1997) (in fight, danger of death, argument and embarrassing personal experiences) shown to guarantee the 'crisis' required in a narrative. Such findings have implications as regards claims of a universal model of narrative; and the general view that one narrative-structure model may be suitable for all personal narratives is re-examined. By way of conclusion, the study formulates a 'variationist' model of narrative 'grammar' that combines core, optional and culturally variant features. It is suggested that such a model may begin to capture how an individual's social and cultural background, as well as story topic, can function as decisive factors in determining narrative form.

    Media stylistics

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    In this chapter we review the concept of ‘media stylistics’. In particular, we disentangle the polysemy of these two terms which, when combined, describe but can also obscure work in this area; and we discuss key themes and concerns which emerge. Through analysis of two short extracts of media discourse in English, we elaborate a distinction between two alternative emphases: study of media language as concerned with the capabilities associated with changing technologies for conveying linguistic messages (e.g. language use in telegraphy, radio, or instant messaging); and study of media language as commentary on modern society’s dominant communication forms, which tend to take an electronic ‘media’ form. In the first emphasis, media discourse is important in understanding the social functions of language and as regards social change. In the second emphasis, media language is more a matter of linguistic resources being used to communicate within an array of contemporary media choices whose availability is simply taken as a social fact. In later stages of the chapter we examine interaction between these different emphases at the level of media ‘genres'. In the formation of media genres, we argue, patterns of linguistic choice are superimposed on a given technical infrastructure and history of media capabilities. Distinctive media styles gradually evolve from each such combination to serve specific and changing expressive and communicative purposes. We conclude with discussion of the implications of this view of media technologies and forms as regards the development of new communicative styles on the Internet

    Supervised learning based multimodal MRI brain tumour segmentation using texture features from supervoxels

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    BACKGROUND: Accurate segmentation of brain tumour in magnetic resonance images (MRI) is a difficult task due to various tumour types. Using information and features from multimodal MRI including structural MRI and isotropic (p) and anisotropic (q) components derived from the diffusion tensor imaging (DTI) may result in a more accurate analysis of brain images. METHODS: We propose a novel 3D supervoxel based learning method for segmentation of tumour in multimodal MRI brain images (conventional MRI and DTI). Supervoxels are generated using the information across the multimodal MRI dataset. For each supervoxel, a variety of features including histograms of texton descriptor, calculated using a set of Gabor filters with different sizes and orientations, and first order intensity statistical features are extracted. Those features are fed into a random forests (RF) classifier to classify each supervoxel into tumour core, oedema or healthy brain tissue. RESULTS: The method is evaluated on two datasets: 1) Our clinical dataset: 11 multimodal images of patients and 2) BRATS 2013 clinical dataset: 30 multimodal images. For our clinical dataset, the average detection sensitivity of tumour (including tumour core and oedema) using multimodal MRI is 86% with balanced error rate (BER) 7%; while the Dice score for automatic tumour segmentation against ground truth is 0.84. The corresponding results of the BRATS 2013 dataset are 96%, 2% and 0.89, respectively. CONCLUSION: The method demonstrates promising results in the segmentation of brain tumour. Adding features from multimodal MRI images can largely increase the segmentation accuracy. The method provides a close match to expert delineation across all tumour grades, leading to a faster and more reproducible method of brain tumour detection and delineation to aid patient management

    Effect of thermomechanical processing defects on fatigue and fracture behaviour of forged magnesium

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    The microstructural origins of premature fatigue failures were investigated on a variety of forged components manufactured from AZ80 and ZK60 magnesium, both at the test specimen level and the full-scale component level. Both stress and strain-controlled approaches were used to characterize the macroscopically defect-free forged material behaviour as well as with varying levels of defect intensities. The effect of thermomechanical processing defects due to forging of a industrially relevant full-scale component were characterized and quantified using a variety of techniques. The fracture initiation and early crack growth behaviour was deterministically traced back to a combination of various effects having both geometric and microstructural origins, including poor fusion during forging, entrainment of contaminants sub-surface, as well as other inhomogeneities in the thermomechanical processing history.             At the test specimen level, the fracture behaviour under both stress and strain controlled uniaxial loading was characterized for forged AZ80 Mg and a structure-property relationship was developed. The fracture surface morphology was quantitatively assessed revealing key features which characterize the presence and severity of intrinsic forging defects.  A significant degradation in fatigue performance was observed as a result of forging defects accelerating fracture initiation and early crack growth, up to 6 times reduction in life (relative to the defect free material) under constant amplitude fully reversed fatigue loading.             At the full-scale component level, the fatigue and fracture behaviour under combined structural loading was also characterized for a number of ZK60 forged components with varying levels of intrinsic thermomechanical processing defects. A novel in-situ non-contact approach (utilizing Digital-Image Correlation) was used as a screening test to establish the presence of these intrinsic defects and reliably predict their effect on the final fracture behaviour in an accelerated manner compared to conventional methods

    MicroRNA expression profiles in pediatric dysembryoplastic neuroepithelial tumors.

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    © Springer Science+Business Media New York 2015Among noncoding RNAs, microRNAs (miRNAs) have been most extensively studied, and their biology has repeatedly been proven critical for central nervous system pathological conditions. The diagnostic value of several miRNAs was appraised in pediatric dysembryoplastic neuroepithelial tumors (DNETs) using miRNA microarrays and receiving operating characteristic curves analyses. Overall, five pediatric DNETs were studied. As controls, 17 samples were used: the FirstChoice Human Brain Reference RNA and 16 samples from deceased children who underwent autopsy and were not present with any brain malignancy. The miRNA extraction was carried out using the mirVANA miRNA Isolation Kit, while the experimental approach included miRNA microarrays covering 1211 miRNAs. Quantitative real-time polymerase chain reaction was performed to validate the expression profiles of miR-1909* and miR-3138 in all samples initially screened with miRNA microarrays. Our findings indicated that miR-3138 might act as a tumor suppressor gene when down-regulated and miR-1909* as a putative oncogenic molecule when up-regulated in pediatric DNETs compared to the control cohort. Subsequently, both miRNA signatures might serve as putative diagnostic biomarkers for pediatric DNETs.Peer reviewedFinal Accepted Versio

    The impact of the COVID-19 pandemic on the learning and wellbeing of secondary school students: a survey in Southern Europe

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    The transition from the traditional model of learning and teaching to full online mode had to be implemented in many countries, in an extremely short time, as the 2020-2021 school year was in mid-stream. Secondary education, which includes students in the age range of 12-18, faced many challenges in this rapid change, as many research studies have shown. Researchers raise questions regarding the readiness of the secondary education community to transition to fully online learning. The pilot study reported in this paper deals with the impact of the transition to online learning on secondary schools in southern European countries. More specifically, this paper presents the results of a literature survey and an empirical survey using an online questionnaire which captured non-traceable responses from secondary schools that, voluntarily and anonymously, completed the questionnaire. The questions were mainly closed, with some open-ended questions for students to fill in. The study also aims to capture data on the socio-economic dimension, accessibility/ availability of the necessary technologies that enable online learning, as well as the families’ employment status and their ability to support students. A total of 90 students participated (62% female, 28% male) from three Mediterranean countries. The students’ perspectives as seen by the students themselves along with the difficulties and the issues they faced are compared and contrasted. This investigation offers a pedagogical and socio-technical analysis and highlights the needs for wellbeing as well as quality learning and teaching in the new social distance reality

    VEGFR1 signaling in retinal angiogenesis and microinflammation

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    Five vascular endothelial growth factor receptor (VEGFR) ligands (VEGF-A, -B, –C, -D, and placental growth factor [PlGF]) constitute the VEGF family. VEGF-A binds to VEGF receptors 1 and 2 (VEGFR1/2), whereas VEGF-B and PlGF only bind VEGFR1. Although much research has been conducted on VEGFR2 to elucidate its key role in retinal diseases, recent efforts have shown the importance and involvement of VEGFR1 and its family of ligands in angiogenesis, vascular permeability, and microinflammatory cascades within the retina. Expression of VEGFR1 depends on the microenvironment, is differentially regulated under hypoxic and inflammatory conditions, and it has been detected in retinal and choroidal endothelial cells, pericytes, retinal and choroidal mononuclear phagocytes (including microglia), Müller cells, photoreceptor cells, and the retinal pigment epithelium. Whilst the VEGF-A decoy function of VEGFR1 is well established, consequences of its direct signaling are less clear. VEGFR1 activation can affect vascular permeability and induce macrophage and microglia production of proinflammatory and proangiogenic mediators. However the ability of the VEGFR1 ligands (VEGF-A, PlGF, and VEGF-B) to compete against each other for receptor binding and to heterodimerize complicates our understanding of the relative contribution of VEGFR1 signaling alone toward the pathologic processes seen in diabetic retinopathy, retinal vascular occlusions, retinopathy of prematurity, and age-related macular degeneration. Clinically, anti-VEGF drugs have proven transformational in these pathologies and their impact on modulation of VEGFR1 signaling is still an opportunity-rich field for further research

    Alzheimer's disease biomarkers in Black and non-Hispanic White cohorts: A contextualized review of the evidence

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    Black Americans are disproportionately affected by dementia. To expand our understanding of mechanisms of this disparity, we look to Alzheimer's disease (AD) biomarkers. In this review, we summarize current data, comparing the few studies presenting these findings. Further, we contextualize the data using two influential frameworks: the National Institute on Aging–Alzheimer's Association (NIA-AA) Research Framework and NIA's Health Disparities Research Framework. The NIA-AA Research Framework provides a biological definition of AD that can be measured in vivo. However, current cut-points for determining pathological versus non-pathological status were developed using predominantly White cohorts—a serious limitation. The NIA's Health Disparities Research Framework is used to contextualize findings from studies identifying racial differences in biomarker levels, because studying biomakers in isolation cannot explain or reduce inequities. We offer recommendations to expand study beyond initial reports of racial differences. Specifically, life course experiences associated with racialization and commonly used study enrollment practices may better account for observations than exclusively biological explanations

    Transgender and Gender Nonconforming Youths’ Public Facilities Use and Psychological Well-Being: A Mixed-Method Study

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    Purpose: In this study, we explored experiences and feelings of safety in public facilities in relation to psychological well-being among transgender and gender nonconforming (TGNC) youth in the Midwest in the summer of 2016, in the context of ongoing legislative proposals and regulations regarding school and public bathroom use in the United States. Methods: We used a mixed-method approach, with (1) a self-administered, paper-and-pencil survey of 120 TGNC youth, focusing on differences of self-esteem, resilience, quality of life (QoL), perceived stigma, feelings of safety, and experiences of public facility use and (2) two focus group interviews (n = 9) in which TGNC youth discussed individual perceptions, attitudes, and experiences of bathroom use outside participants’ homes. The samples consisted predominantly of individuals assigned female at birth and currently of trans-masculine identity. Results: TGNC youth in our sample who reported that they had felt unsafe in bathrooms due to appearance or gender identity had significantly lower levels of resilience (mean(felt safe) = 125.7 vs. mean(felt unsafe) = 116.1; p = 0.03, Cohen’s d = 0.44) and QoL (mean(felt safe) = 59.1 vs. mean(felt unsafe) = 51.9; p = 0.04, Cohen’s d = 0.39), compared to those who felt safe. Meanwhile, feeling unsafe in bathrooms was associated with a greater level of perceived LGBT stigma (mean(felt safe) = 2.3 vs. mean(felt unsafe) = 2.6; p = 0.03, Cohen’s d = 0.41) and problematic anxiety in the past year (2 (1) = 4.06; p = 0.04). Individuals in the focus groups provided specific examples of their experiences of and concerns about locker room or bathroom use in public facilities, and on the impact of school bathroomrelated policies and legislation on them. Conclusion: Perceptions of safety related to bathroom use are related to psychological well-being among TGNC youth. Our predominantly trans-masculine youth sample indicated that choice of bathroom and locker room use is important and that antiharassment policies need to support students’ use of their choice of bathrooms. This is particularly important information given debate of so-called bathroom bills, which attempt to restrict public bathroom use for TGNC youth, creating less choice and more stress and fear among these individuals
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