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Articular cartilage is a tissue specifically adapted to a specific niche with a low oxygen tension (hypoxia), and the presence of such conditions is a key factor in regulating growth and survival of chondrocytes. Zinc deficiency has been linked to cartilage-related disease, and presence of Zinc is known to provide antibacterial benefits, which makes its inclusion attractive in an in vitro system to reduce infection. Inclusion of 1% zinc oxide nanoparticles (ZnONP) in poly octanediol citrate (POC) polymer cultured in hypoxia has not been well determined. In this study we investigated the effects of ZnONP on chondrocyte proliferation and matrix synthesis cultured under normoxia (21% O2 ) and hypoxia (5% O2 ). We report an upregulation of chondrocyte proliferation and sulfated glycosaminoglycan (S-GAG) in hypoxic culture. Results demonstrate a synergistic effect of oxygen concentration and 1% ZnONP in up-regulation of anabolic gene expression (Type II collagen and aggrecan), and a down regulation of catabolic (MMP-13) gene expression. Furthermore, production of transcription factor hypoxia-inducible factor 1A (HIF-1A) in response to hypoxic condition to regulate chondrocyte survival under hypoxia is not affected by the presence of 1% ZnONP. Presence of 1% ZnONP appears to act to preserve homeostasis of cartilage in its hypoxic environment.

Alternating current sources are mainly used in bioelectrical impedance devices. Nowadays 50 -100 kHz bioelectrical impedance devices are commonly used for body composition analysis. High frequency bioelectrical impedance analysis devices are mostly used in bioimpedance tomography and blood analysis. High speed op-amps and voltage comparators are used in this circuit. Direct current feedback is used to prevent delay. An NChannel J-FET transistor was used to establish the voltage controlled gain amplifier (VCG). A sine wave signal has been applied as input voltage. The value of this signal should be constant in 170 mV rms to keep the output current in about 1 mA rms. Four frequencies; 100 kHz, 1 MHz, 2 MHz and 3.2 MHz were applied to the circuit and the current was measured for different load resistances. The results showed that the current was stable for changes in the resistor load, bouncing around an average point as a result of bouncing DC feedback.

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The findings for strengthening and repair of implant materials are stepping up to ensure better protection of the patients. The utilization of composite resin is favourable to combat this challenge. However, it being a brittle material does not entitle it to be used in the design. Hence, epoxy resin combining with silicon oxide filler from the rice husk; is a relatively new material in biomedical engineering, enable it to meet its fullest strength and flexibility. Work was performed at laboratory to extract the silicone compound from rice husk and as well investigate the compressive strength of rice husk filled resin material. Initially the rice husk was experimented by undergoing pre-treatment, chemical treatment and incineration process to obtain silicone compound. The silicone compound was later mixed with epoxy resin at different percentage of filler. In the final stage, the compressive strength of rice husk filled resin was analyzed and affirmed experimentally based on the ASTM standards. The results obtained were then analyzed using analytical software SPSS. Epoxy resin filled with 20% silica from rice husk gave the optimum compressive strength of 90 Mpa.

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An activity of human body can be recorded by the method known as electrocardiography (ECG). The research carried out was to design a new prototype ECG device with wireless capability for the recording of ECG parameters. The idea of this novel project was to achieve wireless transmission of the ECG parameters at the clinician side to make it easy for the clinician and also it will be helpful for the clinician to monitor more than one patient at a time. The prototype comprised of analogue portion followed by a digital portion which was controlled by PIC16F877A. The programming was done through turbo while the software was built on Lab View/CVI 8.0 platform. The goal was achieved but there were a minor issue that it rendered unwanted results due to the patient movement. This problem can be further rectified by more proper shielding.