394 research outputs found

    The role of concern about falling on stepping performance during complex activities

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    Background There is limited understanding of the underlying mechanisms explaining the role of concern about falling on fall risk in older people. Anxiety is known to interact with cognitive resources and, as people get older, they require more cognitive resources to maintain balance. This might affect an individual's ability to perform cognitive-motor tasks concurrently. The aim of this study was to investigate the effect of a visuospatial dual-task on stepping performance in older people with and without concern about falling and the impact of repeating this task in those with high concern about falling. Methods Three-hundred-eight community-dwelling older people, aged 70 to 90 years old, participated in the study. Participants were asked to perform a Choice Stepping Reaction Time (CSRT) task in two conditions; once without any other tasks (single task condition), and once while simultaneously performing a visuospatial task (dual-task condition). Participants were asked to rate their levels of concern and confidence specifically related to each of the 25 stepping trials (before/after). We also measured general concern about falling, affect, and sensorimotor and cognitive functioning. Results Total stepping reaction times increased when participants also performed the visuospatial task. The relation between general concern about falling and stepping reaction time, was affected by sensorimotor and executive functioning. Generalised linear mixed models showed that the group with moderate to high levels of general concern about falling had slower total stepping reaction times than those with lower levels of concern about falling, especially during the dual-task condition. Individuals with greater general concern about falling showed reduced confidence levels about whether they could do the stepping tasks under both conditions. Repeatedly performing the stepping task reduced the immediate task-specific concern about falling levels and increased confidence in all participants. Conclusions These findings reveal that people with higher general concern about falling experienced more difficulties during a dual-task condition than people with lower levels of concern. Of further interest, better sensorimotor and cognitive functioning reduced this effect. Graded exposure has potential to reduce concern about falling during fear-evoking activities, especially in conjunction with therapies that improve balance, mood and cognitive function

    Near-infrared optical imaging of nucleic acid nanocarriers in vivo.

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    International audienceNoninvasive, real-time optical imaging methods are well suited to follow the in vivo distribution of nucleic acid nanocarriers, their dissociation, and the resulting gene expression or inhibition. Indeed, most small animal imaging devices perform bioluminescence and fluorescence measurements without moving the animal, allowing a simple, rapid, and cost-effective method of investigation of several parameters at a time, in longitudinal experiments that can last for days or weeks.Here we help the reader in choosing adapted near-infrared (NIR) fluorophores or pairs of fluorophores for Förster resonance energy transfer assays, imaging of reporter genes, as well as nanocarriers for in vivo gene and siRNA delivery. In addition, we present the labeling methods of these macromolecules and of their payload and the protocols to detect them using bioluminescence and NIR fluorescence imaging in mice

    Validity and responsiveness of the French version of the Örebro musculoskeletal pain screening questionnaire in chronic low back pain

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    The assessment of a broad range of biopsychosocial aspects is important in the rehabilitation of patients with chronic low back pain (CLBP) for the prediction of outcome as well as for evaluation. The objective of this study was to test the responsiveness, construct validity and predictive value of the A-rebro Musculoskeletal Pain Screening Questionnaire (OMPSQ) compared to other instruments widely used to assess biopsychosocial aspects in patients with CLBP. 111 patients with CLBP admitted to an inpatient rehabilitation completed a set of questionnaires on biopsychosocial aspects at baseline and at discharge. Ninety-eight patients responded at three months for an assessment of the return to work status. Responsiveness of the OMPSQ, the ability to detect change in the construct of interest, was investigated by a set of hypotheses on correlations with widely used questionnaires. We tested the hypothesis that the changes in the OMPSQ would vary along with the responses in the Patient's Global Impression of Change. Prediction of disability at discharge, work status at three months and time to return to work was evaluated with linear, logistic and cox regression models. The OMPSQ showed good predictive values for disability and return to work and construct validity of the instrument was corroborated. Seventy-nine percent of our hypotheses for responsiveness could be confirmed, with the OMPSQ showing the second highest change during the rehabilitation. The OMPSQ can also be applied in patients with CLBP, but for the assessment of change in psychosocial variables one should add specific questionnaires

    Convergence and Perturbation Resilience of Dynamic String-Averaging Projection Methods

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    We consider the convex feasibility problem (CFP) in Hilbert space and concentrate on the study of string-averaging projection (SAP) methods for the CFP, analyzing their convergence and their perturbation resilience. In the past, SAP methods were formulated with a single predetermined set of strings and a single predetermined set of weights. Here we extend the scope of the family of SAP methods to allow iteration-index-dependent variable strings and weights and term such methods dynamic string-averaging projection (DSAP) methods. The bounded perturbation resilience of DSAP methods is relevant and important for their possible use in the framework of the recently developed superiorization heuristic methodology for constrained minimization problems.Comment: Computational Optimization and Applications, accepted for publicatio

    Computational case-based redesign for people with ability impairment: Rethinking, reuse and redesign learning for home modification practice

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    Home modification practice for people with impairments of ability involves redesigning existing residential environments as distinct from the creation of a new dwelling. A redesigner alters existing structures, fittings and fixtures to better meet the occupant's ability requirements. While research on case-based design reasoning and healthcare informatics are well documented, the reasoning and process of redesign and its integration with individual human functional abilities remains poorly understood. Developing a means of capturing redesign knowledge in the form of case documentation online provides a means for integrating and learning from individual case-based redesign episodes where assessment and interventions are naturally linked. A key aim of the research outlined in this thesis was to gain a better understanding of the redesign of spaces for individual human ability with the view to computational modelling. Consequently, the foundational knowledge underpinning the model development includes design, redesign, case-based building design and human functional ability. Case-based redesign as proposed within the thesis, is a method for capturing the redesign context, the residential environment, the modification and the transformational knowledge involved in the redesign. Computational simulation methods are traditionally field dependent. Consequently, part of the research undertaken within this thesis involved the development of a framework for analysing cases within an online case-studies library to validate redesign for individuals and a method of acquiring reuse information so as to be able to estimate the redesign needs of a given population based on either their environment or ability profile. As home modification for people with functional impairments was a novel application field, an explorative action-based methodological approach using computational modelling was needed to underpin a case-based reasoning method. The action-based method involved a process of articulating and examining existing knowledge, suggesting new case-based computational practices, and evaluating the results. This cyclic process led to an improvement cycle that included theory, computational tool development and practical application. The rapid explosion of protocols and online redesign communities that utilise Web technologies meant that a web-based prototype capable of acquiring cases directly from home modification practitioners online and in context was both desirable and achievable. The first online version in 1998-99, encoded home modification redesigns using static WebPages and hyperlinks. This motivated the full-scale more dynamic and robust HMMinfo casestudies prototype whose action-based development is detailed within this thesis. The home modification casestudies library results from the development and integration of a novel case-based redesign model in combination with a Human- Activity-Space computational ontology. These two models are then integrated into a relational database design to enable online case acquisition, browsing, case reuse and redesign learning. The application of the redesign ontology illustrates case reuse and learning, and presents some of the implementation issues and their resolution. Original contributions resulting from this work include: extending case-based design theory to encompass redesign and redesign models, distinguishing the importance of human ability in redesign and the development of the Human-Activity-Space ontology. Additionally all data models were combined and their associated inter-relationships evaluated within a prototype made available to redesign practitioners. v Reflective and practitioner based evaluation contributed enhanced understanding of redesign case contribution dynamics in an online environment. Feedback from redesign practitioners indicated that gaining informed consent to share cases from consumers of home modification and maintenance services, in combination with the additional time required to document a case online, and reticence to go public for fear of critical feedback, all contributed to a less than expected case library growth. This is despite considerable interest in the HMMinfo casestudies website as evidenced by web usage statistics. Additionally the redesign model described in this thesis has practical implications for all design practitioners and educators who seek to create new work by reinterpreting, reconstructing and redesigning spaces

    Development and external validation of multivariable risk models to predict incident and resolved neuropathic pain:a DOLORisk Dundee study

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    Neuropathic pain is difficult to treat, and an understanding of the risk factors for its onset and resolution is warranted. This study aimed to develop and externally validate two clinical risk models to predict onset and resolution of chronic neuropathic pain. Participants of Generation Scotland: Scottish Family Health Study (GS; general Scottish population; n = 20,221) and Genetic of Diabetes Audit and Research in Tayside Scotland (GoDARTS; n = 5236) were sent a questionnaire on neuropathic pain and followed- -up 18 months later. Chronic neuropathic pain was defined using DN4 scores (≥ 3/7) and pain for 3 months or more. The models were developed in GS using logistic regression with backward elimination based on the Akaike information criterion. External validation was conducted in GoDARTS and assessed model discrimination (ROC and Precision-Recall curves), calibration and clinical utility (decision curve analysis [DCA]). Analysis revealed incidences of neuropathic pain onset (6.0% in GS [236/3903] and 10.7% in GoDARTS [61/571]) and resolution (42.6% in GS [230/540] and 23.7% in GoDARTS [56/236]). Psychosocial and lifestyle factors were included in both onset and resolved prediction models. In GoDARTS, these models showed adequate discrimination (ROC = 0.636 and 0.699), but there was evidence of miscalibration (Intercept = − 0.511 and − 0.424; slope = 0.623 and 0.999). The DCA indicated that the models would provide clinical benefit over a range of possible risk thresholds. To our knowledge, these are the first externally validated risk models for neuropathic pain. The findings are of interest to patients and clinicians in the community, who may take preventative or remedial measures. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00415-022-11478-0

    The comitology game: European policymaking with parliamentary involvement

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    This paper discusses institutional reforms that might strengthen the role of the European Parliament in the policymaking process of the European Union. Using simple game theory, the paper analyzes the working properties of the different implementation procedures that are known as ‘comitology’. The Council of the European Union employs these procedures when it delegates some of its policymaking power to the Commission as part of Union legislation. We show how the balance of power is determined by the current comitology procedures, and how this balance would change if the role of the European Parliament were strengthened in the comitology game
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