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Cancer is a disease that begins with abnormal proliferation of cells. Genes inside each cell has issued the necessary orders to the cell. Sometimes these commands in a cell are undefined and cell has abnormal behavior and after a while some of abnormal cells can circulate in blood or change into tumors. In A numerical study was carried out on the heating effect of magnetic nanoparticles used in hyperthermia with the goal of attaining a desired rise of temperature at a particular point of location of the tumor situated inside the muscle. A numerical scheme is proposed to solve the bioheat transfer problem in a two zone tissue in spherical geometry with blood perfusion and metabolism. The analytical solution evidences the accuracy of the numerical scheme and examines the results in the literature. Bio-heat equation is used to predict the temperature rise in term of characteristics of the magnetic nanoparticles, applied magnetic field and the tissue. Results show that the strength of applied AC magnetic field has the minor effect, the volume fraction and the frequency of applied AC magnetic field has moderate effect and the diameter of nanoparticles has the major effect on the temperature rise. among materials investigated in this study, FePt has the most pronounced effect. Also, the temperature rise for a position- independent perfusion rate is larger than that found for a position-dependent perfusion rate. Likewise, the temperature rise for a temperature-dependent metabolism rate is larger than that found for a temperature-independent metabolism rate.

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In the present work, the thermal effects of a CW laser on skin tissues with blood perfusion are simulated. For this purpose, a one-dimensional medium is considered that is exposed to the laser beams from one side and the other side is at the constant temperature (37℃) because of being touched by other parts of the body. The laser beams are considered to be collimated and perpendicular to the surface of the tissue. The skin tissue is a strong anisotropic scattering medium and is assumed to be gray with black walls. Also, the blood perfusion is considered in the bioheat transfer equation of the skin tissue. The governing equations of this problem are radiative heat transfer coupled with conductive heat transfer that the discrete ordinates method, finite volume method and scaling method is used to solve the radiative transfer equation, the energy equation and to model the anisotropic scattering of the tissue, respectively. Validation of the model is performed by comparison with the other related works. Then, the effects of different optical and physical parameters of tissue such as conduction-radiation parameter, scattering albedo, extinction coefficient, blood perfusion and the effects of laser power on the time of temperature increase of the tissue and thermal penetration depth are studied. It should be mentioned that the results of the present study show valuable guidance for understanding the coupled light and bioheat transport in tissues in therapy, surgery and diagnostic tasks.