12 research outputs found

    The 'reach' of Digital Language Archives: towards criteria for evaluation

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    Over the last decade, and with the help of digital media and technologies, archives (with the focus here on archives for endangered and minority languages) have extended their focus from preservation to also becoming facilities for dissemination. Their innovations have largely been on ‘discovery’: firstly by encouraging digitisation and inclusion of analogue and obscure materials, and by partnership with funding institutions to support the creation of new, ‘born digital’ language resources; and secondly through online provision of language resources via web catalogues driven by standardised metadata and in some cases providing enhanced discovery through web portals aggregating the holdings of multiple archives. These advances have increased the visibility, relevance and authority of archives for language-related disciplines and for language-speaker communities. This paper considers a broader set of parameters describing the ‘reach’ of archives, where ‘reach’ includes (a) archives’ understanding of their key audiences in order to provide appropriate services for them, e.g. identifying a range of relevant audiences, their languages of access, their varied technological and information literacies, interface design and usability; (b) discovery, drawing on the understandings of audiences in order to help them browse, navigate, search, identify and select their items of interest; (c) delivery, i.e. making available selected resources according to users’ preferences whether by download, view-in-browser, through apps or other means; (d) access management such that resource delivery follows depositors’ and communities’ preferences, and where users have ways of applying for and negotiating for access; (e) information accessibility, where the actual desired content is accessible to users, whether in terms of contextualisation or appropriate complexity, language, or modality; and finally (f) feedback channels, where users can utilise the archive to provide feedback to depositors or to enhance deposits with user-generated content. Through considering how a number of archives are providing such services, we can see their transition from repositories of memory to facilities for fostering participation and understanding

    Low agreement between cardiologists diagnosing left ventricular hypertrophy in children with end-stage renal disease

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    Background: Monitoring of the appearance of left ventricular hypertrophy (LVH) by echocardiography is currently recommended for in the management of children with End-stage renal disease (ESRD). In order to investigate the validity of this method in ESRD children, we assessed the intra- and inter-observer reproducibility of the diagnosis LVH. Methods. Echocardiographic measurements in 92 children (0-18 years) with ESRD, made by original analysists, were reassessed offline, twice, by 3 independent observers. Smallest detectable changes (SDC) were calculated for continuous measurements of diastolic interventricular septum (IVSd), Left ventricle posterior wall thickness (LVPWd), Left ventricle end-diastolic diameter (LVEDd), and Left ventricle mass index (LVMI). Cohen's kappa was calculated to assess the reproducibility of LVH defined in two different ways. LVHWT was defined as Z-value of IVSd and/or LVPWd>2 and LVHMI was defined as LVMI> 103 g/m 2 for boys and >84 g/m2 for girls. Results: The intra-observer SDCs ranged from 1.6 to 1.7 mm, 2.0 to 2.6 mm and 17.7 to 30.5 g/m2 for IVSd, LVPWd and LVMI, respectively. The inter-observer SDCs were 2.6 mm, 2.9 mm and 24.6 g/m2 for IVSd, LVPWd and LVMI, respectively. Depending on the observer, the prevalence of LVHWT and LVHMI ranged from 2 to 30% and from 8 to 25%, respectively. Kappas ranged from 0.4 to 1.0 and from 0.1 to 0.5, for intra-and inter- observer reproducibility, respectively. Conclusions: Changes in diastolic wall thickness of less than 1.6 mm or LVMI less than 17.7 g/m2 cannot be distinguished from measurement error in individual children, even when measured by the same observer. This limits the use of echocardiography to detect changes in wall thickness in children with ESRD in routine practice

    Prospective Evaluation of Sleep Apnea as Manifestation of Heart Failure in Children

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    In adults with heart failure, central sleep apnea (CSA), often manifested as Cheyne–Stokes respiration, is common, and has been associated with adverse outcome. Heart failure in children is commonly caused by dilated cardiomyopathy (DCM). It is unknown whether children with heart failure secondary to DCM have CSA, and whether CSA is related to the severity of heart failure. In this prospective observational study, 37 patients (<18 year) with heart failure secondary to DCM were included. They underwent polysomnography, clinical and laboratory evaluation and echocardiographic assessment. After a median follow-up time of 2 years, eight patients underwent heart transplantation. CSA (apnea–hypopnea index [AHI] ≄1) was found in 19 % of the patients. AHI ranged from 1.2 to 4.5/h. The occurrence of CSA was not related to the severity of heart failure. Three older patients showed a breathing pattern mimicking Cheyne–Stokes respiration, two of whom required heart transplantation. CSA was found in 19 % of the children with heart failure secondary to DCM. No relation was found with the severity of heart failure. In a small subset of children with severe DCM, a pattern mimicking Cheyne–Stokes respiration was registered

    Atrial function in Fontan patients assessed by CMR: Relation with exercise capacity and long-term outcomes

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    Objective: To assess the role of atrial function on exercise capacity and clinical events in Fontan patients. Design: We included 96 Fontan patients from 6 tertiary centers, aged 12.8 (IQR 10.1–15.6) years, who underwent cardiac magnetic resonance imaging and cardiopulmonary exercise testing within 12 months of each other from 2004 to 2017. Intra-atrial lateral tunnel (ILT) and extracardiac conduit (ECC) patients were matched 1:1 with regard to age, gender and dominant ventricle. The pulmonary venous atrium was manually segmented in all phases and slices. Atrial function was assessed by volume-time curves. Furthermore, atrial longitudinal and circumferential feature tracking strain was assessed. We determined the relation between atrial function and exercise capacity, assessed by peak oxygen uptake and VE/VCO2 slope, and events (mortality, listing for transplant, re-intervention, arrhythmia) during follow-up. Results: Atrial maximal and minimal volumes did not differ between ILT and ECC patients. ECC patients had higher reservoir function (21.1 [16.4–28.0]% vs 18.2 [10.9–22.2]%, p = .03), lower conduit function and lower total circumferential strain (13.8 ± 5.1% vs 18.0 ± 8.7%, p = .01), compared to ILT patients. Only for ECC patients, a better late peak circumferential strain rate predicted better VE/VCO2 slope. No other parameter of atrial function predicted peak oxygen uptake or VE/VCO2 slope. During a median follow-up of 6.2 years,

    Six-Minute Walk Test as a Predictor for Outcome in Children with Dilated Cardiomyopathy and Chronic Stable Heart Failure

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    Cardiopulmonary exercise testing is an important tool to predict prognosis in children and adults with heart failure. A much less sophisticated exercise test is the 6 min walk test, which has been shown an independent predictor for m

    Dobutamine stress testing for the evaluation of atrial and diastolic ventricular function in Fontan patients

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    Contains fulltext : 231524.pdf (publisher's version ) (Open Access)OBJECTIVE: To assess the atrial and ventricular diastolic function response to dobutamine stress in Fontan patients, and to relate these measurements to exercise capacity and events during the follow-up. METHODS: We performed a secondary analysis of a cross-sectional multicentre study of Fontan patients with intra-atrial lateral tunnel (ILT) or extracardiac conduit (ECC) modification. Subjects underwent cardiac MRI during rest and low-dose dobutamine stress, and cardiopulmonary exercise testing. Atrial and diastolic ventricular function parameters were derived from volume-time curves.Medical records were abstracted for a composite end-point of death, listing for transplant, arrhythmia and reintervention. Spearman's r correlation tests and Cox proportional hazards models were used to assess the relation between the dobutamine response for atrial and diastolic ventricular function and outcomes, including exercise capacity. RESULTS: We included 57 patients (26 ECC; 31 ILT) aged 12.8 (IQR (10.3-15.5)) years. During dobutamine stress atrial cyclic volume change increased (3.0 (0.4-5.9) mL/m(2), p<0.001), as did early (1.9 (-1.6 to 3.6) mL/m(2), p=0.001) and late emptying volume (2.2 (0.2-4.4) mL/m(2), p<0.001).Ventricular early filling decreased (-1.6 (-5.7 to 0.7) mL/m(2),p=0.046) and ventricular late filling increased (1.0 (-0.4 to 3.4) mL/m(2),p<0.001) while stroke volume remained similar.Only for patients with the ECC modification, atrial early emptying volume increase correlated with peak oxygen uptake (ρ=0.66,p=0.002). No other parameter related to exercise capacity.During a median 7.1-year follow-up, 22 patients reached the composite endpoint. No parameter predicted events during the follow-up. CONCLUSIONS: Dobutamine stress augmented atrial reservoir and pump function for Fontan patients. Atrial early emptying reserve related to exercise capacity in ECC patients. No other atrial or diastolic ventricular function parameter related to outcomes

    Distribution of strain patterns in children with dilated cardiomyopathy

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    Item does not contain fulltextOBJECTIVES: This study aimed to evaluate the predicting value of quantitative and qualitative dyssynchrony parameters as assessed by two-dimensional speckle tracking echocardiography (STE) on outcome in children with dilated cardiomyopathy (DCM). Furthermore, the reproducibility of these parameters was investigated. BACKGROUND: In previous studies in adults with heart failure, several dyssynchrony parameters have been shown to be a valuable predictor of clinical outcome. METHODS: This multicenter, prospective study included 75 children with DCM and 75 healthy age-matched controls. Using STE, quantitative (time to global peak strain and parameters describing intraventricular time differences) and qualitative dyssynchrony parameters (pattern analysis) of the apical four-chamber, three-chamber, two-chamber views, and the short axis of the left ventricle were assessed. Cox regression was used to identify risk factors for the primary endpoints of death or heart transplantation. Inter-observer and intra-observer variability were described. RESULTS: During a median of 21 months follow-up, 10 patients (13%) reached an endpoint. Although quantitative dyssynchrony measures were higher in patients as compared to controls, the inter-observer and intra-observer variability were high. Pattern analysis showed mainly reduced strain, instead of dyssynchronous patterns. CONCLUSIONS: In this study, quantitative dyssynchrony parameters were not reproducible, precluding their use in children. Qualitative pattern analysis showed predominantly reduced strain, suggesting that in children with DCM dyssynchrony may be a minor problem
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