655 research outputs found
Combining electrical stimulation mediated by iterative learning control with movement practice using real objects and simulated tasks for post-stroke upper extremity rehabilitation
No full textObjective: task specific training and Electrical stimulation (ES) are techniques used in rehabilitation of the upper extremity post stroke. This study describes the feasibility of using a rehabilitation system that combines personalised, precisely controlled levels of ES to the anterior deltoid, triceps and finger and wrist extensors during goal-oriented activity utilising real objects from daily life. Materials and methods: four chronic stroke participants undertook seventeen intervention sessions, each of one hour duration. During each session, participants performed goal-orientated tasks while Iterative learning control (ILC) updated the ES signal applied to each muscle group. The update was based on the difference between the ideal and actual movement in the previous attempt at the task, measured using Microsoft Kinect and PrimeSense sensors. The control system applied the minimum amount of ES required with a view to facilitating success at each given task while maximising voluntary effort. Results: preliminary results demonstrate that ES mediated by ILC resulted in a statistically significant improvement in range of movement in all four joint angles studied (shoulder flexion; elbow, wrist and index finger extension) over 17 intervention sessions. Additionally, participants required significantly less extrinsic support for each task. The tasks and system is described and initial intervention data are reported. Discussion: the feasibility of using this system for assisting upper limb movement has been demonstrated. A large scale pilot RCT is now required
Inner Detector session: envelopes, structures and services studies/G Tappern. ID cooling review/G Hallewell
No full textGoal Orientated stroke rehabilitation utilising electrical stimulation, iterative learning and Microsoft Kinect
No full textAn upper-limb stroke rehabilitation system is developed that assists patients in performing real world functionally relevant reaching tasks. The system provides de-weighting of the arm via a simple spring support whilst functional electrical stimulation is applied to the anterior deltoid and triceps via surface electrodes, and to the wrist and hand extensors via a 40 element surface electrode array. Iterative learning control (ILC) is used to mediate the electrical stimulation, and updates the stimulation signal applied to each muscle group based on the error between the ideal and actual movement in the previous attempt. The control system applies the minimum amount of stimulation required, maximising voluntary effort. Low-cost, markerless motion tracking is provided via a Microsoft Kinect, with hand and wrist data provided by an electrogoniometer or data glove. The system is described and initial experimental results are presented for a stroke patient starting treatment
Goal-orientated Functional Rehabilitation using Electrical Stimulation and Iterative Learning Control for Motor Recovery in the Upper Extremity Post-Stroke.
No full textThere is increasing evidence that electrical stimulation (ES) combined with task specific training is effective in the recovery of upper extremity dysfunction following stroke. The aim of this study is to develop a rehabilitation system that delivers precisely controlled levels of stimulation to the shoulder, elbow and wrist during goal-oriented activity which utilises everyday real objects. Iterative learning control (ILC) is used to mediate the ES and updates the stimulation signal applied to each muscle group based on the error between the ideal and actual movement in the previous attempt. The control system applies the minimum amount of stimulation required, maximising voluntary effort with a view to facilitating success at each given task. Markerless motion tracking is provided via a Microsoft Kinect, with hand and wrist data measured by an electrogoniometer. Preliminary results show that ES mediated by ILC has successfully facilitated movement across the shoulder, elbow and wrist of chronic stroke patients. Overall, joint error has reduced for all participants with the mean error across all joints showing reductions for all participants. Furthermore, there was a significant reduction in extrinsic support necessary for each task. The system is described and initial intervention data are reported
Aspects of the use of saturated fluorocarbon fluids in high energy physics
No full textThe excellent dielectric properties of saturated (CnF(2n+2)) fluorocarbons have allowed their use in direct immersion liquid cooling of electronics, including the Cray series of supercomputers, and as heat transfer media in vapour phase soldering and burn-in testing of electronics. Their high UV optical transparency, non-flammability and non-toxicity have led to their use as liquid and gas radiator media for Cherenkov detectors: such fluids have been used as liquid and gaseous radiators in numerous particle physics and astroparticle physics experiments.The systems used to circulate and purify fluorocarbon Cherenkov radiator fluids often rely on thermodynamic cycles similar to those of the refrigerants recently developed to replace chlorofluorocarbons. Since such new refrigerants are designed to disintegrate under UV exposure in the upper atmosphere, they are correspondingly not radiation-resistant, and cannot be used for direct cooling of particle detectors in demanding radiation environments, such as at the CERN Large Hadron Collider. However the pure saturated fluorocarbon molecules are extremely radiation resistant due to the presence of only single C-F bonds. Their use as evaporative refrigerants was pioneered at CPPM for the ATLAS pixel detector and has been chosen for the cooling of all the silicon detectors in the experiment, and also for cooling the semiconductor vertex detectors of the ALICE and TOTEM experiments at LHC. These fluids are also used as liquid phase cooling fluids in ATLAS and CMS. The evaporative mode exploits the latent heat or enthalpy of vaporization, allowing the circulation of a lower coolant mass than in a monophase cooling system of the same refrigerative capacity. Coupled with the lower fluorocarbon viscosity - compared with aqueous antifreeze-based coolants - this permits the use of narrower delivery tubing to the detectors, resulting in a smaller '%X0'contribution to the detector material budget. Ultrasonic techniques for the vapour phase analysis of fluorocarbon Cherenkov radiators were developed as an alternative to UV refractometry for the SLD Cherenkov Ring Imaging Detector at the Stanford Linear Accelerator Center during the 1980s. Subsequently the technique has been used in many other Ring Imaging Cherenkov Detectors and also in the petro-chemical industry and for MOCVD (metal organic chemical vapour deposition) manufacture of semiconductors. The technique has also been demonstrated to have possible application in the vapour phase analysis of gas mixtures used in clinical anesthesia. Such vapour phase analysis techniques are again under evaluation for the possible cooling of the upgraded ATLAS silicon tracker. The work of the author related to various applications of these versatile fluorocarbon fluids is discussed in this memoire
Crystal-Based Hybrid Single Photon Detector Development for the KM3NeT Cubic Kilometre Neutrino Telescope
No full textScintillating crystal-based hybrid photon detectors have been demonstrated as viable single photon detectors since 1996 in the Lake Baikal neutrino telescope. Prior to this, the Philips XP2600 'SMART' X-HPD had been developed under the DUMAND program, while more recently, developments at CERN have demonstrated the advantages of a true concentric geometry with a scintillator at the geometric centre of a spherical photocathode, giving almost 100% electrostatic collection efficiency over a ~ 3*pi solid angle coverage. Under a collaboration within the Groupement d'Intêret Scientifique cooperation signed between Photonis S.A. and the IN2P3 (Institut National de Physique Nucléaire et de Physique des Particules) division of the CNRS, a series of quasi-spherical X-HPDs will be developed with sizes ranging between 8" and the maximum that can be constructed for fitting in a standard 17" optical pressure sphere for use in a deep sea neutrino telescope. The thrust of this R&D will be to investigate the industrialisation of the X-HPD to the point where it represents a significant cost reduction per cubic kilometre of instrumented volume compared to conventional PMTs, thereby allowing for extremely large telescope target volumes. Such gains will arise from industrialisation of an all-glass envelope construction, the internal deposition of enhanced efficiency bi-alkali photocathodes, and either from cost reductions in the central scintillating crystal or the use of a deposited phosphor
Development of active pixel vertex detectors for high luminosity particle physics applications
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The present status of pixel detector developments for high energy physics collider applications
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