Hong Kong domestic health spending: Financial years 1989/90 to 2009/10

published_or_final_versio

Hong Kong domestic health spending: Financial years 1989/90 to 2008/09

published_or_final_versio

A Preliminary Study on Robot-Assisted Ankle Rehabilitation for the Treatment of Drop Foot

This paper involves the use of a compliant ankle rehabilitation robot (CARR) for the treatment of drop foot. The robot has a bio-inspired design by employing four Festo Fluidic muscles (FFMs) that mimic skeletal muscles actuating three rotational degrees of freedom (DOFs). A trajectory tracking controller was developed in joint task space to track the predefined trajectory of the end effector. This controller was achieved by controlling individual FFM length based on inverse kinematics. Three patients with drop foot participated in a preliminary study to evaluate the potential of the CARR for clinical applications. Ankle stretching exercises along ankle dorsiflexion and plantarflexion (DP) were delivered for treating drop foot. All patients gave positive feedback in using this ankle robot for the treatment of drop foot, although some limitations exist. The proposed controller showed satisfactory accuracy in trajectory tracking, with all root mean square deviation (RMSD) values no greater than 0.0335 rad and normalized root mean square deviation (NRMSD) values less than 6.7%. These preliminary findings support the potentials of the CARR for clinical applications. Future work will investigate the effectiveness of the robot for treating drop foot on a large sample of subjects

Do elderly from developed countries have better oral health-related quality of life? An analysis in 15 countries

Conference Theme: A Global Perspective on Ageing Societie

Mechanical Aspects of Wollastonite Microfibre-reinforced Resin Composites

Poster Session: Dental Materials-Polymer-based Materials VI - presentation no. 2627Objectives: Wollastonite is a naturally-occured calcium inosilicate (CaSiO3) that has needle-like crystalline structure, and also posses apatite formation ability. Thus, it might be potentially useful to create bioactive dental resin composites by using Wollastonite microfibres as reinforcement. The objective of this study was to evaluate the mechanical properties of Wollastonite microfibre-reinforced resin composites (mFRC), with respect to filler dimension and loading volume. Methods: Five types of natural Wollatonite microfibres with various dimensions (Φ3×22μm, Φ9×50μm, Φ9×125μm, Φ5×55μm and Φ15×250μm) and different volume percentage (40, 50 and 60) were loaded in experimental bisGMA/TEGDMA/HEMA resin. An LED curing lamp was used to polymerize the experimental mFRC with respective moulds for three-point bending (2×2×20mm, n=8), compressive (Φ3×6mm, n=8) and notchless triangular prism (NTP) fracture toughness (6×6×6×12mm, n=6) tests. Scanned electron microscopy (SEM) was used to observe the fractured surface. Statistical analysis was done on SPSS (ver. 22, IBM, NY) with level of significance α=0.05. Two-way ANOVA with Tukey post-hoc test was used to investigate the effects of microfibre dimensions and volume on the mechanical parameters, and one-way ANOVA was used to compare the strength. Results: Wollastonite mFRC made by 40 vol% of Φ5×55μm gives the best flexural strength (78.23±10.73 MPa) and fracture toughness (1.14±0.23 MPa●m1/2). Particularly, filler loading of 40 vol% always give a statistically significant higher flexural strength (p<0.01), compressive strength (p<0.05) and fracture toughness (p<0.01) than 60 vol%. Microfibres of approximately 50μm, i.e. Φ9×50μm and Φ5×55μm, give a significant higher flexural (p<0.05) and compressive (p<0.05) strength than Φ3×22μm and Φ15×250μm. The dimensions of Wollatonite microfibres are inversely related to its compressive strength. Conclusions: Wollastonite microfibres filler loading is crucial and far more important than the fibre dimensions for mFRC mechanical properties

Musculoskeletal Model for Path Generation and Modification of an Ankle Rehabilitation Robot

While newer designs and control approaches are being proposed for rehabilitation robots, vital information from the human musculoskeletal system should also be considered. Incorporating knowledge about joint biomechanics during the development of robot controllers can enhance the safety and performance of robot-aided treatments. In this article, the optimal path or trajectories of a parallel ankle rehabilitation robot were generated by minimizing joint reaction moments and the tension along ligaments and muscle-tendon units. The simulations showed that using optimized robot paths, user efforts could be reduced to 80%, thereby ensuring less strain on weaker or stiffer ligaments, etc. Additionally, to limit the moments applied by the robot in stiff or constrained directions, the intended robot path was modified to move the commanded position in the direction opposite to that of the position error. Such online modification of the robot path can lead to a reduction in forces applied by a robot to the subject. Simulation results and experimental findings with healthy subjects using an ankle rehabilitation robot prototype and subsequent statistical analysis further validated that path modification based on ankle joint biomechanics results in a reduction in undesired forces experienced by human users during treatment