Combination of frequency and amplitude-modulated model for the synthesis of normal and wheezing sounds.

Based on communication theory, this study proposes a model to synthesize normal and wheezing sounds. The model included five parts: the flow source as a transmitter, the frequency and amplitude-modulated (FM-AM) sounds, the accompanying noise as a modulator, the airway wall as a medium, and the microphone as a receiver. The hypothesis of modulation builds on that the deviation of frequency and amplitude of the sounds which cause from the deviation of collision speed of the air flow on the wall. The model was successful to simulate the normal breath and wheezing sounds. Furthermore, it provided a correct proof for the CORSA description, which indicates that the wheeze was contained in the domain frequency at 400 Hz, but a number of investigators have suggested that the range is actually between 80-1,600 Hz and 350-950 Hz by filter theory. This study modifies the signal source in Wodicka et al. model, and describes it in functional blocks. In fact, the design of the signal source base on the knowledge of the lung sound studies, especially the analysis of components in the frequency and time domains. We synthesized the required components to reproduce the lung sounds, and proposed a mechanism of wheeze which was examined by the computer simulation in the points of the system engineering view.

Electric compass aided global positioning system navigation for powered wheelchairs.

Powered wheelchairs are an important mobility aid for the elderly and for persons with disability. According to World Health Organization statistics, most of the accidents were due to personal mistakes; if there is an auto-navigating system such as auxiliary, mistaken manipulation will decrease efficiency. This study attempted to improve the global positioning system (GPS) navigation of electric powered wheelchairs (EPWs) through the addition of an electric compass (EC) and tested the navigation of EPWs with EC-aided and non-EC-aided GPS navigation along a 25 m road. According to these tests, the use of the EC significantly reduces the errors in GPS navigation during movements such as go straight ahead, turn right and turn left. Therefore, the navigation reduced the error of the expected trajectories with the EC-aided navigation.

Regulation by ultrasound treatment on the integrin expression and differentiation of osteoblasts.

It has been shown that ultrasound (US) stimulation accelerates fracture healing in the animal models and in clinical studies. However, the mechanism by which US achieves these outcomes is not clear. Here we investigated the effect of US stimulation on the differentiation of osteoblasts and osteoclastogenesis. The effect of different intensities of US stimulation (1 MHz, continuous wave) on the osteoblastic cell line MC3T3-E1 or primary cultured osteoblasts was examined. Flow cytometry showed that US stimulation at 125 mW/cm2 for 10 min transiently increased the surface expression of alpha2, alpha5, and beta1 integrins in both MC3T3-E1 and primary osteoblasts. Fluorocytochemistry showed that the actin cytoskeleton also reorganized in response to US stimulation. When the MC3T3-E1 cells were cultured in differentiation medium containing vitamin C and beta-glycerophosphate, long-term US stimulation (10 min/day for 11 days) increased mineralized nodule formation, collagen content, and alkaline phosphatase activity. The intensity at 125 mW/cm2 exerts the most prominent action. Effect of long-term US stimulation on the osteoclastogenesis was also examined. US stimulation at a power of 62.5 or 125 mW/cm2 markedly inhibited RANKL plus M-CSF-induced osteoclastic differentiation from bone marrow stromal cells. These findings suggest that US has a regulatory effect on the integrin expression and the differentiation of osteoblasts and osteoclastogenesis, which may contribute to the beneficial effects of US on the fracture repair.

The Development of M3S-Based GPS Navchair and Tele-Monitor System.

The purpose of this study is to develop a M3S- Based GPS navigation system for power wheelchair. The wheelchair steered with GPS and electronic compass can move automatically toward a specific destination through a GIS-Map in the computer. The topic of this study is to help people with disabilities regain independence of transportation in specific areas of their daily activities. This system is now designed to operate in special locations, for example, campuses or airports. Safety of the system is enhanced according to "M3S", which is an international standard for power wheelchair. In the proposed architecture, modules are easily and securely integrated to the wheelchair, which includes a tele-monitor system implemented with computer network, mobile-phone and physiological sensors. Bio-signals, wheelchair location and other information of the user are acquired by the nursing staff or any other medical personnel by using this system.