L'impact de la chorée sur les mouvements alternés rapides des patients ayant la maladie de Huntington = The impact of chorea on rapid alternating movements in patients with Huntington's disease

Le but de cette étude était d'isoler l'impact de la chorée sur les mouvements volontaires, pour mieux évaluer le rôle des mouvements involontaires sur les perturbations motrices observées chez les patients ayant la maladie de Huntington. Les mouvements involontaires du corps ainsi que les actions motrices volontaires furent enregistrés simultanément, à l'aide d'un système de pistage magnétique, chez quinze patients choréiques ayant la maladie de Huntington ainsi que chez quinze sujets contrôle en bonne santé de même âge et sexe. Il a été demandé aux participants d'accomplir deux tâches distinctes; une de mouvements alternés rapides (RAM) qui permettra de quantifier l'hypokinésie et la bradykinésie, et une tâche de poursuite manuelle (MT) qui fournira une mesure quant à l'intrusion des chorées lors de mouvements précis. Les patients ayant la maladie de Huntington ont obtenu de meilleurs résultats comparativement aux sujets contrôles lors de la tâche RAM, démontrant ainsi l'absence de bradykinésie chez ces sujets. Lors de la tâche MT, les patients ayant la maladie de Huntington ont démontré une déviation par rapport à l'emplacement de la cible réduisant ainsi leur habileté à reproduire sa vitesse. De plus, une corrélation fût établie entre l'erreur au niveau des performances et l'amplitude des chorées du corps, illustrant l'effet néfaste des chorées lors de mouvements précis. Ces résultats démontrent clairement que la bradykinésie n'est pas un symptôme de la maladie de Huntington lorsque des chorées sont présentes, mais que les chorées sont la principale cause d'erreur de performance lors de mouvements précis. Donc, les patients atteints de la maladie de Huntington bénéficieraient grandement de traitements visant à réduire les chorées tout en maintenant une fonction motrice adéquate. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Huntington, Bradykinesia, Chorée, Quantification, Parkinson

Employing vision-based sensing for long-term monitoring

This is the author accepted manuscript.Despite the crucial role of structural health monitoring (SHM), traditional approaches rely on contact-based sensors which are both costly and lack automation. Vision-based sensing techniques such as Digital Image Correlation (DIC) have recently emerged as a viable substitute, due to their non-contact nature and low cost. To date, however, the long-term performance of DIC has not been evaluated. This study assesses DIC for long-term displacement monitoring. Firstly, the robustness of the monitoring of ambiently excited structures over long periods is examined. This is achieved through the measurement of drift of control points. Then, correlation is examined between the drift measurements and the ambient temperature, to examine the influence of temperature on the robustness of the DIC measurements. After, the effectiveness of employing DIC for monitoring ambiently excited structures is examined. Towards this aim, the displacements of the midspan of the experimental bridge structure are monitored for one month and compared with those of a traditional contact-based sensor, i.e., a Linear Variance Displacement Transducer (LVDT). Finally, to further demonstrate the effectiveness of employing DIC measurements for ambiently excited structures, a correlation is sought between the midspan displacements and the ambient temperature. Concerning the robustness of the long-term DIC measurements, the drift was found to be relatively small (i.e., equal to 0.06 mm) whilst the temperature was found to potentially influence this. With regard to the overall effectiveness of long-term monitoring with DIC, the study found that non-contact sensing has comparable accuracy to the LVDT, with a correlation coefficient equal to 0.996, root mean square error of 0.012 mm, and mean absolute error of 0.010 mm. Moreover, the correlation of DIC measurements with temperature showed its effectiveness in capturing complex structural behaviours (e.g., extremely slow and small movements) typically associated with ambiently excited structures. Whilst this study is only on a small-scale structure, it paves the way for the employment of vision-based on large-scale structures enabling the general use of DIC for SHM.Innovate U

Disabled Environmentalisms

This chapter develops an agenda for the fostering of disabled environmentalism, demonstrating how such an agenda, through the centralising of disabled bodies, can enable environmental justice movements to be truly inclusive of all people's needs. It provides a broad overview of the barriers that disabled people can experience when attempting to participate in environmentalism – both in everyday environmentalism as well as in the organisation and implementation of more public forms of activism. It also provides both the context for demonstrating the necessity of developing disabled environmentalisms, as well as a space for readers to critically reflect on the inclusivity of their own environmental practices. The chapter highlights the importance of ‘cripping’ or centralising the disabled body within environmental justice movements in order to develop a disabled environmentalism disentangled from its normative roots and, thus, capable of imagining truly socially just environmental futures