Articles
Journal of Thermal Biology (18790992)129
Microwave thermal therapy for liver cancer presents challenges due to the potential for healthy tissue damage. This study explores the use of hybrid magnetic nanofluids to optimize treatment effectiveness while minimizing side effects. Preoperative modeling was employed to determine the optimal nanoparticle type, concentration, and combination for enhanced thermal efficiency. Three magnetic nanoparticles—maghemite, magnetite, and FccFePt—were analyzed, both individually and in hybrid compositions. Results demonstrated that increasing nanoparticle concentration significantly reduced treatment duration and minimized healthy tissue necrosis. At 0.1 % concentration, treatment times for maghemite, magnetite, and FccFePt were 3, 67, and 90 s, with corresponding healthy tissue loss-to-tumor volume ratios of 0.06, 3.08, and 4.36. Lowering the concentration to 0.05 % increased treatment times to 46, 126, and 129 s, raising tissue loss ratios to 1.88, 6.65, and 8.36. Notably, hybrid nanoparticle compositions showed divers but non-uniform effects, with some combinations marginally improving treatment efficacy while others had negligible impact. The hybridization of maghemite and FccFePt reduced necrosis time, but its influence on overall treatment efficiency was inconsistent. These findings underscore the potential of hybrid nanoparticles to enhance microwave ablation therapy; however, they also highlight the complexity of nanoparticle interactions, emphasizing the need for precise selection and concentration optimization to achieve superior treatment outcomes while preserving healthy tissue. © 2025 Elsevier Ltd
Computer Methods in Biomechanics and Biomedical Engineering (10255842)27(6)pp. 775-784
To prevent frostbite in cold environments, proper dimensions and materials for different parts of shoes along with the optimal design of shoe geometry were investigated. Furthermore, the optimal geometry of shoes was computed using an optimization algorithm to provide maximum thermal protection for the foot while having the lowest weight. The results showed that the length of the shoe sole and the thickness of the sock are the most effective parameters in foot protection against frostbite. Using thicker socks, which only increased the weight by roughly 11%, enhanced the minimum foot temperature by more than 2.3 times. HIGHLIGHTS Optimal design of shoe geometry is used to prevent frostbite in cold environments. A model of a biothermal nonlinear model is developed for the barefoot. Length of the shoe sole and the thickness of the sock are the most effective parameters in protecting the foot against frostbite. For the selected weather conditions, the toes are most likely to have frostbite. The best shoe for the selected weather conditions is the shoe that has the highest amount of thermal insulation in the toe area. © 2023 Informa UK Limited, trading as Taylor & Francis Group.
Heat Transfer Engineering (1457632)45(14)pp. 1222-1235
The amount of drug in the eye depends on various factors such as genetics, layers structure, temperature distribution, and aqueous humor flow field. The heat transfer, fluid flow field, and drug delivery in the eye are numerically simulated using a three-dimensional model. The results are compared with experimental data on human and rabbit eyes. The effect of ambient temperature on the flow field in standing and supine positions was investigated. Then the transfer of drug concentration by intravitreal injection method was simulated using the obtained flow field. The results showed that the temperature distribution and the position of the eye relative to the direction of gravity have a significant role in the process of concentration transfer in the anterior segment of the eye. The results showed that in an intravitreal injection method, the drug has a significant concentration in the posterior part of the eye. In the intravitreal injection method with the injection of 1.25 mg of the drug, the maximum concentration in the vitreous humor is 1575.5 μg/ml, and the drug vanishes into the eye after 30 days. In this case, the maximum drug concentration in the aqueous humor is 30.16 μg/ml, which occurs after 1.5 days. © 2023 Taylor & Francis Group, LLC.
International Journal of Thermal Sciences (12900729)203
The comprehension of heat transfer mechanisms and their profound implications on biological heat transfer is of paramount importance in the advancement of cancer treatments across all types of malignancies. In the present study, the intricate interplay between Pennes' biothermal principles, Maxwell's electromagnetic equations, and heat generation via a one-slot microwave antenna is resolved numerically. By administering magnetite nanoparticles into malignant tumors, an induced field is engendered, ultimately leading to tumor ablation. By manipulating the microwave frequency, the resultant field is assessed to ascertain the optimal therapeutic modality for this dangerous ailment. The investigation incorporates varying volume percentages of nanoparticles, namely 0.1, 0.05, 0.01, and 0.005 percent, yielding tumor necrosis durations of 2.8, 7.3, 34, and 69 s, respectively. Furthermore, the loss of healthy tissue is quantified as 4.8 %, 15.4 %, 65 %, and 139 %, respectively. Consequently, a direct correlation emerges between the percentage of nanoparticles employed and the diminished treatment duration, as well as reduced adverse effects on healthy tissues, leading to improved patient comfort and minimized thermal-induced injury. Additionally, the influence of frequency within the microwave range (0.3–10 GHz) is probed. Accordingly, when the nanoparticles are injected into the tumor, the frequency has no meaningful difference in the treatment result. © 2024
