Effects of electromagnetic fields exposure on the antioxidant defense system

Objective: The present study examined variations in the degree of smartphone use behavior among male and female adolescents as well as the association between various degrees of smartphone use beha...

Gender differences in the association of smartphone use with the vitality and mental health of adolescent students

The effective atomic numbers (Z
 eff) and effective electron density (N
 e) of different type concrete have been measured and the results were compared with the calculation obtained using the mass attenuation coefficients (μ/ρ) obtained via XCOM in the photon energy range of 1 keV–100 GeV. Six different concrete in where marble has been used in the rate of 0, 5, 10, 15, 20, 25 %, has been used in the study.

Effective atomic number and electron density of marble concrete

This is a very comprehensive book with more than 1000 pages, 25 chapters and 53 contributors from various disciplines associated with radiotherapy but predominantly medical physics. It is not a textbook of medical physics or radiation oncology although an extensive reference list at the end of each chapter provides a means of pursuing each topic at greater depth. Advanced physics and mathematics have been kept to a minimum and hence the book is easy to read and accessible to a wide range of readers. The standard technologies ranging from superficial, kilovoltage x-ray through to medical accelerators, brachytherapy, stereotactic radiotherapy and total body irradiation are addressed together with topics such as medical imaging, simulation, computer planning, treatment verification, beam shaping and beam intensity modulation. Each topic is presented in detail but in a simple, clear manner liberally supported with graphs, diagrams, tables and photographs. Special emphasis has been given to equipment currently available, the basic physical principles of their operation, their design and design specifications. Tendering, commissioning, acceptance testing and quality assurance are also reviewed in detail. Most chapters commence with a historical overview and finish with a summary and description of likely future developments. Approximately one quarter of the chapters describe past, current or evolving technologies not normally available in radiotherapy facilities. These include such topics as particle therapy, tomotherapy, hyperthermia, photodynamic therapy, boron neutron capture and others. These are particularly useful reviews of the state of the art and potential applications. Although the title suggests that this is a book for medical physicists and radiation oncologists, it is more than that. It is relevant to a much wider readership including radiation therapists, dosimetrists, radiation oncology nurses and administrators. It would be an excellent reference book for students of all disciplines associated with radiation oncology and it would therefore be a valuable addition to any radiation oncology or general medical library.

The Modern Technology of Radiation Oncology: A Compendium for Medical Physicists and Radiation Oncologists

Optimization of the radiation shielding capabilities of bismuth-borate glasses using the genetic algorithm

In consideration the radiological properties of materials and studying the scattering processes in atomic and nuclear physics, the effective atomic and mass numbers is widely employed. These numbers have been calculated for any mixed or composite materials in interaction with high energy photons (Linac in radiation therapy). A pair equation in terms of these numbers is obtained. The first equation has been derived from the conservation of mass energy law and the second by minimizing the binding energy from the semiempirical mass formula (Myers and Swiatecki formula) that gives a relation between atomic and mass numbers for stable nuclei approximately. By these equations one can obtain the effective atomic and mass numbers for any compound or mixed materials uniquely. These numbers are calculated for some materials and compared with the other studies.

Determination of the effective atomic and mass numbers for mixture and compound materials in high energy photon interactions

Introduction The negative health effects of electromagnetic radiation and psychological dependence are among the major consequences of widespread cell phone use in the general population, especially among adolescents. In this study, the relationship between cell phone use and sleep quality parameters was evaluated. Materials and Methods The study sample consisted of 820 students (305 males and 515 females), recruited from Arak University of Medical Sciences, Arak, Iran. The participants completed Pittsburgh Sleep Quality Index (PSQI) and Cell-phone Overuse Scale (COS); the validity of these questionnaires had been previously confirmed in the Iranian population. Information on demographic characteristics and variables associated with cell phone exposure, such as the frequency and duration of phone calls and number of messages was collected in a separate questionnaire. Results Data analysis showed that cell phone overuse was significantly correlated with sleep quality and its components. Moreover, the results indicated that the global PSQI score and some sleep components were significantly correlated with several variables related to cell phone use. Based on the findings, the mean PSQI score was significantly different among heavy and light cell phone users (P<0.01). Moreover, among heavy cell phone users, females had a higher global PSQI score, compared to males (P<0.01).   Conclusion According to the literature and the present study, services provided by modern cell phones, along with the extensive use of these devices, could be considered as potential threats to public health, especially adolescents’ sleep quality. In order to reach a definitive conclusion, further systematic and laboratory studies are required.

http://ijmp.mums.ac.ir/article_7140_3c3381f496765e70eef3da6b141641f2.pdf

The Correlation between Cell Phone Use and Sleep Quality in Medical Students

Background: Considering that some vital organs exist in the head and neck region, the treatment of tumors in this area is a crucial task. The existence of air cavities, namely sinuses, disrupt the radiotherapy dose distribution. The study aims to analyze the effect of maxillary, frontal, ethmoid and sphenoid sinuses on radiotherapy dose distribution by Monte Carlo method. Materials and Methods: In order to analyze the effect of the cavities on dose distribution, the maxillary, frontal, ethmoid and sphenoid sinus cavities were simulated with (3×3.2×2) cm 3 , (2×2×3.2) cm 3 , (1×1×1.2) cm 3 and(1×1×2) cm 3 dimensions. Results: In the analysis of the dose distribution caused by cavities, some parameters were observed, including: inhomogeneity of dose distribution in the cavities, inhomogeneity of dose on the edges of the air cavities and dispersion of the radiations after the air cavity. The amount of the dose in various situations showed differences: before the cavity a 0.64% and a 2.76% decrease, a 12.06% and a 17.17% decrease in the air zone, and a 2.25% and a 5.9% increase after the cavity. Conclusion: The results indicate that a drop in dose before the air cavities and in the air zone occurs due to the lack of scattered radiation. Furthermore, the rise in dose was due to the passage of more radiation from the air cavity and dose deposition after the air cavity. The changes in dose distribution are dependent on the cavity size and depth. As a result, this has to be noted in the treatment planning and MU calculations of the patient.

https://jbpe.sums.ac.ir/article_43385_54be6df9b8aef63c0d4b1d9aee649097.pdf

Investigating the Effect of Air Cavities of Sinuses on the Radiotherapy Dose Distribution Using Monte Carlo Method

Background: Megavoltage beams used in radiotherapy are contaminated with secondary electrons Different parts of linac head and air above patient act as a source of this contamination This contamination can increase damage to skin and subcutaneous tissue during radiotherapy  Monte Carlo simulation is an accurate method for dose calculation in medical dosimetry and has an important role in optimization of linac head materials The aim of this study was to calculate electron contamination of Varian linac Materials and Method: The 6MV photon beam of Varian (2100 C/D) linac was simulated by Monte Carlo code, MCNPX, based on its company’s instructions The validation was done by comparing the calculated depth dose and profiles of simulation with dosimetry measurements in a water phantom (error less than 2%) The Percentage Depth Dose (PDDs), profiles and contamination electron energy spectrum were calculated for different therapeutic field sizes (5×5 to 40×40 cm 2 ) for both linacs  Results: The dose of electron contamination was observed to rise with increase in field size The contribution of the secondary contamination electrons on the surface dose was 6% for 5×5  cm 2  to 27% for 40×40  cm 2 , respectively  Conclusion: Based on the results, the effect of electron contamination on patient surface dose cannot be ignored, so the knowledge of the electron contamination is important in clinical dosimetry It must be calculated for each machine and considered in Treatment Planning Systems

http://jbpe.sums.ac.ir/article_43182_562ab4b9ceb2dbb6daac27b56b797c2c.pdf

Evaluation of Electron Contamination in Cancer Treatment with Megavoltage Photon Beams: Monte Carlo Study

Background
Electromagnetic fields (EMF) are associated with oxidative stress, which is in turn associated with reactive oxygen species (ROS), anemia, and hypoxia.

/pdf/influence-of-electromagnetic-fields-on-lead-toxicity-a-study-3ltmkev9oa.pdf

Mohamad Reza Bayatiani

Papers

Determination of the effective atomic and mass numbers for mixture and compound materials in high energy photon interactions

The Correlation between Cell Phone Use and Sleep Quality in Medical Students

Investigating the Effect of Air Cavities of Sinuses on the Radiotherapy Dose Distribution Using Monte Carlo Method

Evaluation of Electron Contamination in Cancer Treatment with Megavoltage Photon Beams: Monte Carlo Study

Influence of Electromagnetic Fields on Lead Toxicity: A Study of Conformational Changes in Human Blood Proteins