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Radiation therapy typically targets and destroys tumor cells with the least amount of damage to healthy cells by utilizing an ionizing radiation beam. Therapeutic doses of ionizing radiation applied to the neck and head could cause a wide range of oral health issues. The components of the treatment plan that affect the degree of damage include the irradiation field, total dosage absorbed, fractionation, and the patient's age at the start of therapy. The presented work examined the impact of ionizing radiation on the structure and hardness of dental materials. For one week, a different form of ionizing radiation was used (continuous X-ray (bremsstrahlung radiation), Gamma radiation, and Beta radiation). The sample was irradiated at the University of Baghdad, College of Science, Department of Physics at Nuclear Laboratory. The sample (three different types of samples) was chosen randomly from patients between the ages of 25 and 40 years old, the first sample (3rd Molar upper irradiated by continuous x-ray radiation (bremsstrahlung), the second sample (Central lower irradiated by Gamma radiation) and the third sample (Upper first Premolar the sample irradiated by Beta radiation from radioactive source). For studying the direct effect of ionizing radiation on dental rigidity, the sample was tested by Vickers hardness, and to study the micromorphology of the sample, the sample was measured using scanning electron microscopy (SEM), both before and after exposure. The microhardness results demonstrated that the teeth exposed to radiation had much-reduced microhardness in the third molar upper exposed to x-ray irradiation; its microhardness values increased in comparison to non-irradiated teeth. This has been especially true for the central lower, exposed to gamma rays, and the upper first premolar, exposed to beta particles. The impact on microhardness was connected to the fact that the irradiated teeth showed more crack lines in SEM images compared to non-irradiated teeth. Because dentine has a lesser compressive strength than enamel, it may be why dentine cracks were more noticeable. The dentine-enamel junction exhibited a bigger crack width in the irradiated specimens, indicating greater damage to those specimens. It is one of radiation therapy's most dangerous side effects. Given that there were more detrimental impacts on oral structure, ionizing radiation has demonstrated a significant interaction with organic tissues. [ABSTRACT FROM AUTHOR]

This paper arose from the teaching of Models in Biology to take a new approach to problems they are familiar with, to come up with an articulate verbal model after a mental effort, to express it in rigorous mathematical terms, to solve corre-sponding equations (with the help of computers), and to analyze and interpret experimental data in terms of their (mathematical) models. We will investigate a mathematical model of branching by solving a system of partial equations (PDEs). The results will describe the success or failure of the growth of the fungus species studied, and we used some codes (pplane7, Pdepe) in numerical analysis because direct mathematical solution was difficult. [5] Tip death due to hyphal death, dichotomous branch-ing [ABSTRACT FROM AUTHOR]

The most important machine elements of the braking system are the brake disc and pads. During the braking process, the braking torque is necessary to decelerate the speed of the vehicle or stop it. High amount of frictional heat will be generated during the braking process due to the sliding between the moving part (brake disc) and fixed parts (brake pads). The present research involves two parts, in the first part it will be investigated the effects of difeeerent properties of three friction materials (St37-2, G95 and HCC) on the thermal behavior of the brake system. While, in the second part, the expedite work will be achieved to measure the temperature distribution during the braking process. A parametric study was achieved to find out the effect of different factors such as angular velocity, applied pressure and material propertiese on the behavior and performance of the brake system. The minimum values of temperature obtained when using friction material (HCC) which is about 52.3 °C, G95 was 53.8 °C, and for St37-2 was 56.8 °C. The temperature increases with velocity and pressure, maximum values of temperature is obtained when using (St37-2) pad material and minimum value is obtained when using (HCC) pad material. [ABSTRACT FROM AUTHOR]

The automobile contains several very important parts, one of which is the friction clutch. Its importance comes from being it is a mechanical coupling device that plays the role of connecting and transmitting the torque generated in the engine to the gear set in the gearbox. The friction material is an important parameter due to withstand the mechanical and thermal load generated in the clutch system. This paper focused on studying the thermal behavior of four different friction lining materials (LUK, Tiger, G95, and HCC) to identify the temperature distribution for each material separately and then compare these materials to arrive at the best material that you can choose in the dry clutch design. Modeling of the model was done by the method of finite element and with the help of the ANSYS program to perform numerical simulations and show results. It may be determined that the thermoelastic behavior of the clutch is influenced by the type of frictional lining material used. After comparing the data, it was discovered that the materials (HCC and G95) were vulnerable to clutch activation for long periods. In the current investigation, the lining materials stood out because they demonstrated a high thermal efficiency when compared to the other materials in the prior study. [ABSTRACT FROM AUTHOR]

In the present work , we have derived some results for second order differential subordination associated with the Hadamard product concept involving the differential operator. [ABSTRACT FROM AUTHOR]