Biomedical Engineering: Applications, Basis and Communications

It is a tricky task to record electrical signals from the subcutaneous fixed tether assembly in freely moving mouse. The thin and pliable skin of the mouse is easily rent at the sutured incision site by dragging of the external output set during movement. We constructed a light weight chassis that made the output plug-in connector tightly fixed at the muscle. It could resist a lot of pulling force produced by the movement of the mouse. Furthermore, the plug-in connector protruded out off the skin only by a silicone tube. The thin cylinder configuration of the silicone tube made it possible for the incision to be sutured finely and the flexible and smooth characteristics of the silicone tube could buffer the pulling force to avoid subjecting the skin to mechanical tear. A shielded external output cable feature which was light weight and flexible was also made, resulting in less loading on the mouse and without impediment during movement.

The conventional patient-controlled-analgesia (PCA) can be further improved in terms of less drug consumption and better pain control if advanced feedback control algorithm is applied. The purpose of this research was to develop an enhanced patient-controlled analgesia (EPCA) using a hierarchical fuzzy logic control system with two levels and to apply it to patients in an extracorporeal shock wave lithotripsy (ESWL) operation. The two-level control system utilizes the conventional PCA as a basic level on the top of which is added an adaptive self-learning fuzzy logic control (SLFLC) level. Twenty-three patients involved in these clinical trials were to study the clinical effectiveness of EPCA for the management or pain during the ESWL process. A two-button device was designed, one button for severe pain (SP) and another for mild/moderate pain (MP) to investigate the frequencies of analgesic demands or delivery related to either severe or mild/moderate pain. The results show that the average percentage of demand/delivery to total demand/delivery due to MP is significantly higher than that due to SP, which implies the pain levels that most patients experienced were mostly mild to moderate in the ESWL process with the EPCA. The drug consumption of alfentanil with the EPCA is comparable to that with a fixed FLC; however, it is much lower than that with conventional PCA. In conclusion, the efficiency of the therapy, pain relief, and the patients' satisfaction of pain management with the EPCA in the ESWL operation are superior to those with the conventional PCA.

Environmental control units play a role in enabling disabled people to carry out routine and repetitive tasks (e.g. watching TV, making a phone call, etc.) in their home environments. Unfortunately, most commercially available environmental control units are either too expensive or they require the disabled persons' home environments to be remodelled. In this paper we report the development of a low-cost environmental control unit which enables disabled people to control mostly existing consumer electronics with an infrared remote control functionality. Finally, we use a simple scenario to evaluate the performance of the proposed environmental control unit.

Appling magnetic nanoparticle (MNP) in curing cancers has been a significant subject of medical research. A variety of switched-mode resonant inverters using voltage-fed-type high-frequency applicator with power MOSFET (metal oxide semiconductor field effect transistor) gate has been recently developed for medical use in electromagnetic thermotherapy. In this paper, a MNP heating system is presented and the electrical circuit characteristics of resonant components are analyzed. A half-bridge induction heating incorporate component functions directly at the applicator thereby reducing the size, weight, and cost of MNP heating systems. Preliminary heating results show a rise of about 3.8°C with 10-nm MNP for a 220-kHz frequency during the first 20 min.

It is assumed that bosentan, a non-selective ET-1 receptor antagonist, will enhance fracture healing. The aim of this prospective randomized controlled study was to investigate the effects of transcutaneous bosentan administration into diaphyseal bone fractures using radiology, histology, prostaglandin E₂ (PGE₂) and leukotrien C₄ (LTC₄) activity measurements.

A closed diaphyseal fracture was created in the hind limbs following intramedullary rod fixation of Guinea pigs. Bosentan was administred by repetitive weekly 0.1 μg transcutaneous injections into the fracture site. The effects of bosentan were evaluated by radiology and histology on weeks 1, 2 and 4, whereas prostaglandin E₂ (PGE₂)-like and leukotrien C₄ (LTC₄)-like activity was assessed on weeks 1 and 2.

The radiological degree of union (p = 0.001) at the fracture site and cortex-callus ratio (p = 0.02) was significantly better in the bosentan administered site at week 1 when compared to the control. Histology presented an initial stimulation of bone formation on weeks 1 and 2 in the experimental group. PGE₂-like activity was significantly higher (p = 0.002) on week 1 and 2 in the bosentan-administered side. LTC₄-like activity remained constant on week one and decreased on week two.

Transcutaneous repetitive bosentan administration into the fracture site initially stimulated periosteal bone healing that resulted with extracellular matrix mineralization. The inflammatory mediators PGE₂/LTC₄ played a significant role in this process.

In this paper, a biodynamic modeling of the human upper-body at the seated posture subjected to external stimulating forces in both the horizontal and vertical directions is developed. Based on d'Alembert's principle, the non-linear biodynamic equation of the modeling, which has the characteristic of two dimensions and one degree of freedom, is obtained. Furthermore, the responses of frequency and amplitude of the non-linear biodynamic equation is investigated by employing the KB method in the non-linear theory. The responses of realistic human parameters and the external stimulating forces on the modeling are simulated by MATLAB. The results show that the modeling presents the rich non-linear characteristic. It is given and discussed for the parameter identification and stable area of keeping the upper-body stabilization at the seated posture. The paper can be used to explain and estimate the mechanism of maintenance of stable trunk posture due to the mechanical shocks transmitted through the vehicle seat.

A cost-effective and portable Braille printer with low noise is designed in this study. To reach this goal, the compressive printing concept is used and the Braille typesetting, the signal transmission interface module, the signal control module, and the Braille printing cell are designed and integrated. To increase the portability, the Braille printer is designed to use A4 size paper and each page can print at most twenty-four rows and twenty-seven Braille characters in each row. The typesetting of the printing page is designed to contain twenty-seven side-by-side Braille printing cells and each printing cell contains two low cost flapper mechanisms for performing the low noise and cost-effective Braille print. The logic signal control module then controls a total of fifty-four flappers. The logic signals are transmitted through the integrated signal transmission interface module based on two common standard personal computer interfaces: Serial/RS232 and Universal Serial Bus 2.0. Subsequently, the pre-processing software is programmed based on the hardware developed. The integration of the software and hardware is successfully validated, and this newly designed Braille printer can be further used by the visually impaired for self-printing.

In telemedicine, an insecure and vulnerability medicine information system is important for nursing staff and patients. Relatively private information stolen by others still can be corrected. However, if attacked by hackers, mistakes in diagnosis can threaten the patient's life. In order to simplify the procedures in the authentication of telemedicine and to emphasize security in the patient's data, this paper proposes utilizing the symmetric key cryptography and the biometric authentication. We use a face eigenvector to insert the patient's physiological signals and to combine symmetric key cryptography thus protecting the integrity of the patient's data and improving the mode of operations.