Nonlinear three-dimensional finite element analysis of newly designed cementless total hip stems

We designed 2 new types of proximally coated stems (the FMS and FMS-anatomic) based on the endosteal geometry of femora with congenital dislocation or dysplastic hip. The FMS was symmetric while the FMS-anatomic was asymmetric. We compared the proximal fit and fill to the femoral canal, contact stress, relative motion, and load transfer to the femur of 5 stems (FMS, FMS-anatomic, Omnifit, Omniflex, and individual stem) using three-dimensional computer simulation and finite element analysis. The FMS and FMS-anatomic showed a significantly greater fit and fill than conventional stems. The dispersion of the contact stresses and reduction of relative motions in the proximal area were the best in the FMS-anatomic compared to other stems with the exception of the individual stem. In addition, the FMS-anatomic stem transferred most of the load to the proximal femur. Our results suggest that the FMS-anatomic should provide better biomechanical stability at least in the early postoperative period.     

Effect of two-phase fabrication method for the optimum fit of light-polymerized record bases

PURPOSE

The aims of this study were to suggest a method of fabrication of the record base using a light-polymerized resin by applying the two-phase fabrication method for the improvement of the fit of the record base and to compare the degree of fit according to the separation site.

MATERIALS AND METHODS

In the edentulous cast of maxilla, four test groups were considered. In the first, second, third, and fourth test groups (n = 12 in each group) the separation was done at 0, 5, 10, and 15 mm, respectively below the alveolar crest along the palatal plane. For the control group, the record base was made without separating the two sections. The light-body silicone material was injected into the fitting surface of the record base. It was then placed onto the cast and finger pressure was applied to stabilize it in a seated position followed by immediate placement onto the universal test device. Finally, the mass of the impression material was measured after it was removed. ANOVA was performed using the SAS program. For the post-hoc test, the Wilcoxon Rank-Sum test and the Tukey-Kramer HSD test were performed (α = 0.05).

RESULTS

The control group and Group 3, 4 showed significant differences. The Group 3 and 4 showed significantly smaller inside gaps than the control group which was not made with the two-phase fabrication method.

CONCLUSION

The two-stage polymerized technique can improve the fit of the denture base particularly when the separation was made at 10 to 15 mm from the alveolar crest.     

体感交互技术在运动康复领域的应用

本文介绍3 种体感设备EyeToy、Wii 及Kinect 应用于运动功能康复的研究现状。体感交互技术作为一种有效的运动康复技术手段,应用前景广阔。     

Assessing real-time performances of N95 respirators for health care workers by simulated workplace protection factors

To assess performances of N95 respirators for Health Care Workers (HCWs) in a simulatedhealth-care setting, we measured the Simulated Workplace Protection Factors (SWPFs) inreal-time from the volunteers. A total of 49 study subjects, wearing 3 M respirator ModelN95 1860 and 1860S, were fit tested using the OSHA Exercise Regimen. The test subjectswere asked to perform simulated scenarios, including patient assessments, suction, andintravenous injection (IV) treatment. Two TSI PortaCount instruments continuously measuredconcentrations in the respirator and the room concentration. For Quantitative Fit Testing(QNFT), 36 out of 49 (73.5%) passed the fit factor (FF) criteria set at 100 and 13 (26.5%)failed. The results of QNFT were found to have a low correlation with SWPF, withR²=0.32. The geometric means (GM) and geometric standard deviations (GSD) ofSWPF were 68.8 (1.1) for those subjects who passed and 39.6 (1.3) for those who failed.Real-time assessments of SWPF showed that lower SWPFs were; moving head up and down, andbending at the waist. This study identifies the needs for providing different sizes ofrespirators for HCWs and the importance of performing fit tests for HCWs regularly. Andparticular movements were identified as attributing factors affecting more on SWPFs.     

移动医疗网络优化方案

以西南医科大学附属肿瘤医院为例,阐述其移动医疗网络的部署,通过监控临床业务流量及数据分析,提出几种无线网络优化方案,包括无线环境优化、提升信道容量、增加编码效率、接入用户限制几方面,测试结果显示该方案可以有效提高无线网络的性能。     

Are all prostate cancer patients "fit" for salvage radiotherapy?

The indication for salvage radiotherapy (RT) (SRT) in patients with biochemically-recurrent prostate cancer after surgery is based on prostate-specific antigen (PSA) levels at the time of biochemical recurrence. Although there are clear criteria (pT3-pT4 disease and/or positive margins) for the use of adjuvant radiotherapy, no specific clinical or tumour-related criteria have yet been defined for SRT. In retrospective series, 5-year biochemical progression-free survival (PFS) ranges from 35%-85%, depending on the PSA level at the start of RT. Two phase 3 trials have compared SRT with and without androgen deprivation therapy (ADT), finding that combined treatment (SRT+ADT) improves both PFS and overall survival. Similar to adjuvant RT, the indication for ADT is based on tumour-related factors such as PSA levels, tumour stage, and surgical margins. The number of patients referred to radiation oncology departments for SRT continues to rise. In the present article, we define the clinical, therapeutic, and tumour-related factors that we believe should be evaluated before prescribing SRT. In addition, we propose a decision algorithm to determine whether the patient is fit for SRT. This algorithm will help to identify patients in whom radiotherapy is likely to improve survival without significantly worsening quality of life.     

Force during functional exercises on land and in water in older adults with and without knee osteoarthritis: Implications for rehabilitation

Background

Closed kinetic chain and plyometric exercises are commonly used in aquatic rehabilitation because they are believed to reduce joint loading whilst replicating functional tasks. However, the forces and relationship to land-based functional movement is unknown. This study aims to compare vertical ground reaction force during squats, calf raises and jumping in older adults with and without knee osteoarthritis on land and in water.

A low cost fMRI-compatible tracking system using the Nintendo Wii remote

It is sometimes necessary during functional magnetic resonance imaging (fMRI) experiments to capture different movements made by the subjects, e.g. to enable them to control an item or to analyze its kinematics. The aim of this work is to present an inexpensive hand tracking system suitable for use in a high field MRI environment. It works by introducing only one light-emitting diode (LED) in the magnet room, and by receiving its signal with a Nintendo Wii remote (the primary controller for the Nintendo Wii console) placed outside in the control room. Thus, it is possible to take high spatial and temporal resolution registers of a moving point that, in this case, is held by the hand. We tested it using a ball and racket virtual game inside a 3 Tesla MRI scanner to demonstrate the usefulness of the system. The results show the involvement of a number of areas (mainly occipital and frontal, but also parietal and temporal) when subjects are trying to stop an object that is approaching from a first person perspective, matching previous studies performed with related visuomotor tasks. The system presented here is easy to implement, easy to operate and does not produce important head movements or artifacts in the acquired images. Given its low cost and ready availability, the method described here is ideal for use in basic and clinical fMRI research to track one or more moving points that can correspond to limbs, fingers or any other object whose position needs to be known.     

Assisting people with multiple disabilities by actively keeping the head in an upright position with a Nintendo Wii Remote Controller through the control of an environmental stimulation

The latest researches have adopted software technology by applying the Nintendo Wii Remote Controller to the correction of hyperactive limb behavior. This study extended Wii Remote Controller functionality for improper head position (posture) correction (i.e. actively adjusting abnormal head posture) to assess whether two people with multiple disabilities would be able to actively keep the upright head position by controlling their favorite stimulation using a Wii Remote Controller with a newly developed active head position correcting program (AHPCP). The study was performed according to an ABAB design, in which A represented the baseline and B represented intervention phases. Results showed that both participants significantly increased their time duration of maintaining upright head position (TDMUHP) to obtain the desired environmental stimulation during the intervention phases. Practical and developmental implications of the findings were discussed.     

Assisting children with Attention Deficit Hyperactivity Disorder actively reduces limb hyperactive behavior with a Nintendo Wii Remote Controller through controlling environmental stimulation

The latest studies have adopted software technology which turns the Wii Remote Controller into a high-performance limb action detector, we assessed whether two persons with multiple disabilities would be able to control an environmental stimulus through limb action. This study extends the functionality of the Wii Remote Controller to the correction of limb hyperactive behavior to assess whether two children with Attention Deficit Hyperactivity Disorder (ADHD) would be able to actively reduce their limb hyperactive behavior through controlling their favorite stimuli by turning them on/off using a Wii Remote Controller. An ABAB design, in which A represented the baseline and B represented intervention phases, was adopted in this study. Result showed that both participants significantly increased their time duration of maintaining a static limb posture (TDMSLP) to activate the control system in order to produce environmental stimulation in the intervention phases. Practical and developmental implications of the findings are discussed.