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Magnetically stabilized fluidized beds are widely used in various technologies. The study given considers the use of this physical process in the iron ore beneficiation to obtain high-quality magnetite concentrates. For this purpose, a number of devices having different capacities have been developed. A modified Todes formula is proposed to be used to control the process of separating the components of ferromagnetic suspensions in devices of different capacities operating at present, using a mathematical model predicting the porosity and height of the fluidized bed.

Using the algorithm and the results of laboratory studies on grinding of loparite ores from the Lovozero deposit in a ball and rod mill, simulation grinding models were designed based on the transformation of a discrete function of the density distribution of outputs of mineral particle size classes. The model’s adequacy was quantitatively analysed carried out by calculating the determination coefficient without taking into account the constant component of the distribution; for a qualitative assessment of the result the authors used the Cheddock scale. The authors studied the minerals disintegration at ball and rod grinding with the following verification of the proposed algorithm. To identify the distribution of loparite by size classes in the initial ore samples and in the samples obtained in the disintegration taking place at different productivity, the X-ray diffraction analysis and the combined (weight, optical and geometric) methods were used.

Tests of ballistic aircraft on rail tracks in conditions close to real ones are an economically viable alternative to flight tests. Rocket rail tracks exist in the USA, Canada, France, China and a number of other countries. The article con-siders potentially self-oscillating mechanical systems that have a threshold mechanism for the transition from a noise vibrational stable state to a self-oscillatory one, depending on the mode parameters. An algorithm for estimating the damping coefficient of the harmonic components of a particular mode of a complex process is proposed. As an indicator of energy loss of the oscillatory component during resonant interaction, the value of the density of the power spectrum related to the width of the frequency range is taken. Based on the solution of the Fokker-Planck equation for a stochastic process, estimates of the “drift” and “diffusion” coefficients are obtained. A technique for estimating the state of potentially self-oscillatory systems in the form of a set of probabilistic stochastic characteristics is proposed. According to the experimental data of vibration accelerations for the structural elements of the rocket sled with the test object, according to the proposed method, it is possible to make the contribution of the self-oscillations of the elements, if they are pre-sent in a complex vibration process, and also to make estimates of their vibration strength at resonances.

The increase in the speed characteristics of newly developed aircraft models im-poses new requirements on the test bench equipment of rocket-rail tracks, including braking means. In this paper, the method of friction braking in the conditions of a rocket track is considered. A method for calculating the mode of motion of a rocket sled during friction braking and the thermal wear of the friction elements of braking devices occurring at the same time is presented. An example of the calculation of the friction braking of a conditionally specified rocket sled, per-formed according to the presented method, is shown.

Обґрунтовано особливості регулювання формування і збереження екологічно безпечного середовища. Визначено залежність його результативності від інституційного та нормативно-правового забезпечення заходів з підтримки сучасного стану довкілля й збереження природно-ресурсного потенціалу України. З’ясовано сутність Цілей сталого розвитку «Україна-2030», які визначають пріоритети досягнення економічного, соціального та екологічного розвитку країни. Встановлено, що на даному етапі в системі екологічного управління існує невідповідність між новими завданнями та старою структурою, не призначеною для виконання таких завдань. Визначено концептуальні засади регулювання формування та збереження екологічно безпечного середовища як одного з чинників соціальної стабільності та економічного розвитку.

Introduction: In 2014, the incidence of prostate cancer in the Russian Federation was 116.4 per 100,000 population. It is noteworthy that from 2004 to 2014, the proportion of patients with stage I-II prostate cancer increased from 35.5% to 52.5%, while that of patients with stages III and IV disease decreased from 38.4% to 29% and from 22.7% to 16.5%, respectively. All of this allows an increasing number of prostate cancer patients to be treated with radical treatment - low dose-rate brachytherapy. For the first time in this country, we report a clinical trial of low dose-rate brachytherapy for prostate cancer using domestically manufactured I-125 seeds. The successful results of this clinical trial are presented in this article. The aim of this work was to show the clinical efficacy and safety of domestically manufactured I-125 seeds for low dose-rate prostate cancer brachytherapy., Materials and Methods: The clinical trial comprised 36 patients with stage T1-T2 prostate cancer. Patients were randomly assigned according to the risk of cancer progression. Low and intermediate risk groups comprised 30 (83.3%) and 6 (16.7%) patients, respectively. Patients of low risk group underwent brachytherapy alone with the minimum therapeutic dose of 145 Gy. I-125 seeds of two activities, 0.55 and 0.35 mCi per seed were used for implantation. Depending on the prostate volume, from 40 to 80 seeds, 57 on average were implanted. Mean implantation time was 85 minutes. In patients of the intermediate risk group brachytherapy was performed in combination with laparoscopic pelvic lymphadenectomy which was carried out 4-5 weeks prior to brachytherapy., Results: Follow-up examination at 6 months after implantation showed that PSA decreased in all patients on average by 87% from the baseline. No adverse events were reported., Conclusion: The findings of the clinical trials of domestically manufactured I-125 seeds showed they are effective, safe and comply with international standards.

The ROS concentration and proliferation activity (Ki67 expression.marker) have been studied in the periphery blood lymphocytes of Moscow and Obninsk citizens, donors, Chernobyl disaster liquidators, inhabitants of the region contaminated after Chernobyl disaster (Klincy) and individuals with prostate cancer. It was shown that ROS concentration in lymphocytes of the liquidators and residents of the polluted region was lowered. But in lymphocytes of patients with tumors the ROS content was higher in comparison with the control. The cell content with Ki67 expression in lymphocytes of the individuals resided in the polluted region and tumor patients was lowered.

The oxidative status (ROS), markers activation expression (CD69), proliferation activity (Ki67), proapoptotic antigen (CD95) have been investigated on healthy donors and patients with prostatic gland cancer in human blood lymphocytes. The lymphocyte reaction in vitro on γ-irradiation at different doses (0.05-1.0 Gy) has been determined too. It was shown that in these two types of individuals the ROS content does not differ and the reaction on irradiation is not different either. Essential is the difference between the marker expression in lymphocytes of healthy donors and patients with tumour: in individuals with cancer the content of lymphocytes with CD69+ phenotype (in non active situation) and CD95+ increases, the expression of marker Ki67 decreases. The lymphocyte response to irradiation in healthy and tumour lymphocytes is distinguished. Irradiation at doses 0.05-10.0 Gy on tumour patients lymphocytes markers does not influence expression. In healthy donors' lymphocytes the expression of markers is changed considerably, the reaction depends on the marker type: expression of CD69 marker decreases (tendency); expression of Ki67 decreases too; it is unusual that the expression of CD95 changes--it decreases after irradiation at the doses of 0.05-1.0 Gy, then increases with dose. So this work shows the changes in tumour patients' blood lymphocytes in comparison with healthy donors' lymphocytes. The possible mechanisms of the observed phenomenon are discussed.

This study presents the short-term outcomes of conformal external beam radiation therapy given in conjunction with hormone therapy to 110 patients with prostate cancer. We performed a comparative analysis of the rate and degree of radiation reactions and complications following delivery of a total dose of 70 Gy and 72-76 Gy to the tumor. In prostate cancer, a continuous course of dose-escalated conformal radiation therapy resulted in satisfactory tolerance and acceptable levels of late complications.

"The purpose of our paper is to present recent trends of mortality in the former USSR in terms of demographic transition theory.... Analysis of data on mortality dynamics by age and cause of death allows us to consider some features of the progress of the demographic transition.... The principal causes of the discrepancy between the former USSR and Western countries appear to follow first of all from considerably lower living standards.... The second principal cause of unfavourable patterns of mortality was an unhealthy environment in the workplace and at home." The focus is on the 1980s., (excerpt)