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BACKGROUND: This study aimed to investigate the effects of MUVON PLUS, a dietary supplement containing hydrolized collagen, chondroitin sulfate, and vitamin C, on the biomechanical behavior of the knee joint in patients with second-degree osteoarthritis (OA). MATERIAL AND METHOD: The study included 15 participants who underwent biomechanical testing before and after 3 and 6 months of supplement administration. Biometrics and SimiMotion software were used to process and analyze the data. Results showed significant improvements in biomechanical parameters such as joint range of motion, joint torque, and joint stiffness for all patients during the treatment. Improvements were observed across various tests, including horizontal walking, stairs climbing and descending, sitting/standing up from a chair, and knee squats. This improvement in biomechanical performance was also reflected in the patients' reported quality of life. For the stairs climbing test, the maximum flexion-extension angle increased by approximately 7% after 3 months and 12% after 6 months. In the stairs descending test, the maximum flexion-extension angle increased by approximately 8% after 3 months and 19% after 6 months. These results highlight an improvement in mobility for the study participants. CONCLUSIONS: Significant improvements of the biomechanical parameters of the knee joint were found in all patients during the treatment with the MUVON PLUS in all tests, which indicates the clear clinical benefit, revealed by improving the quality of life reported by patients. Overall, the study demonstrated the effectiveness of MUVON PLUS in enhancing the biomechanical behavior of the knee joint in patients with OA, providing valuable insights for future research and treatment.
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Soldering processes are applied in the fabrication of electronic circuits used in most modern domestic and industrial technologies. This article aims to introduce a new soldering technology based on the microwave joining of copper materials used in electronic applications. The study was focused on microwave technology used as the thermal source for soldering. A simulation model of temperature distributions in copper plates with overall dimensions of 50 × 10 × 0.8 mm was developed in order to determine the necessary microwave power for soldering. For 270 °C simulated on the surface of copper plates, the microwave-injected power was determined to be 598.89 W. An experimental program for 600, 650, 700, and 750 W was set in order to achieve soldering of copper plates in less than 1 min. Soldered copper plates were subject to electrical resistance measurements being obtained with variations up to ±1.5% of the initial electrical resistance of the base materials. The quality of joints has also been analyzed through microscopy after the soldering process. In addition, mechanical properties were determined using a universal testing machine. The results have shown similar behavior of the samples layered with SAC on the one-side and double-side but also a significantly lower force before breaking for one-side-layered samples. An economic analysis was performed and the results obtained have shown that in terms of energy efficiency and total costs for microwave soldering compared with manual soldering, microwave soldering is cost-effective for industrial processing.
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During the microwave sintering of a polymer-ceramic composite plasma discharge is experienced. The discharge could occur failure of the power source. The solution proposed by the paper is original, no similar solutions being presented by the literature. It consists of using a polymer-ceramic composite protective panel, to stop the plasma discharge to the entrance of the guiding tunnel. Six composites resulted by combining three polymers, Polytetrafluoroethylene (PTFE), STRATITEX composite and Polyvinylchloride (PVC) with two natural ceramics containing calcium carbonate: Rapana Thomasiana (RT) sea-shells and beach sand were used to build the protective panel.Theoretical balance of the power to the panel was analysed and the thermal field was determined. It was applied heating using 0.6-1.2-1.8-2.4-3.0 kW microwave beam power. The panels were subjected to heating with and without material to be sintered. It was analyzed: RT chemical (CaCO3 as Calcite and Aragonite), burned area (range: 200-4000 mm2) and penetration (range: 1.6-5.5 mm), and thermal analysis of the burned areas comparing to the original data. PTFE-RT composite proved the lowest penetration to 0.6 and 1.2 kW. Other 1.2 kW all composites experienced vital failures. Transformation of the polymer matrix of composite consisted of slightly decreasing of the phase shifting temperature and of slightly increasing of the melting start and liquidus temperature.