Theoretical Investigation of the EPR G-Factor for the Axial Symmetry Ce3+ Center in the BaWO4 Single Crystal

The parameters g-factor (g|| and g⊥) together with the local structure of the Ce3+ center in BaWO4 single crystal (scheelite structure crystals) were theoretically investigated using a complete diagonalization procedure of energy matrix (CDM method). The intrinsic parameters were calculated. It is shown that the experimental and the calculated values of the g-factors are in good agreement. The angular distortion has also been calculated. It was found that the polar angles of the impurity–ligand bonding are smaller than in BaWO4 single crystal (Δθ≈1.00 ) . The validity of the results and the changing in the local environment of the impurity–cerium ion is also discussed.

Имитационная модель оценки артефактов немоноэнергетичности и рассеяния в компьютерной томографии

A simulation model for estimating the beam-hardening and scattering in computed tomography in the geometry of a parallel beam is proposed on the example of inhomogeneous objects with axial symmetry. The modeling algorithm consists of a block of formation of projections and a block of reconstruction of images of object cross sections based on the Abel reverse transformation. The developed algorithm is implemented as a MathCad program. The efficiency of the algorithm and program is demonstrated by the example of a multilayer ball. Estimates of the beam hardening artifacts and scattering of the simulation model are compared with experimental estimates for the radial distributions of the linear attenuation coefficient.

The Additive Input-Doubling Method Based on the SVR with Nonlinear Kernels: Small Data Approach

The problem of effective intellectual analysis in the case of handling short datasets is topical in various application areas. Such problems arise in medicine, economics, materials science, science, etc. This paper deals with a new additive input-doubling method designed by the authors for processing short and very short datasets. The main steps of the method should include the procedure of data augmentation within the existing dataset both in rows and columns (without training), the use of nonlinear SVR to implement the training procedure, and the formation of the result based on the author’s procedure. The authors show that the developed data augmentation procedure corresponds to the principles of axial symmetry. The training and application procedures of the method developed are described in detail, and two algorithmic implementations are presented. The optimal parameters of the method operation were selected experimentally. The efficiency of its work during the processing of short datasets for solving the prediction task was established experimentally by comparison with other methods of this class. The highest prediction accuracy based on both proposed algorithmic implementations of a method among all of the investigated ones was defined. The main areas of application of the developed method are described, and its shortcomings and prospects of further research are given.

Analysis of the Effects of Hyperthermia with Magnetic Nanoparticles on Cancer Tissues

Introduction: Hyperthermia is one of the noninvasive methods of treating cancer. In this method, heat can be generated in several methods. One of these methods is injecting magnetic nanoparticles as a solution into the tumor site and place it in a magnetic field. Methods: The study was analytical one, modeling was performed using computational methods, and in vitro experimental data were used as the boundary conditions. The problem was solved with a geometry consisting of different layers of skin, adjacent tissue, tumor and injection site and assuming axial symmetry. The problem was solved with a geometry consisting of different layers of skin, the adjacent tissue, the tumor and the injection site and assuming axial symmetry. The effect of different injection sites, effect of performing two injections with a smaller volume comparing with an injection with a large volume, and finally the effect of the injected solution on the temperature distribution of the tumor was investigated. Results: Results showed that injections with a smaller volume of solution in different sites would have better results, so that more parts of the tumor would reach to a temperature above 42°c, which is the temperature needed for having cancer cells died. Injection with the temperature of 37°c would be more effective than injection at room temperature and reached the desired temperature in less time. Conclusion: According to the novelty of this investigation in assuming data from empirical experiments on the solution containing cobalt ferrite nanoparticles coated with polyethylene glycol as the boundary condition of the problem in modeling, the study is an important step in a more precise prediction of the clinical conditions occurring through using these methods of hyperthermia.