Search

The aim of this study is to investigate the influence of polymer chemistry on the properties of oral dosage forms produced using selective laser sintering (SLS). The dosage forms were printed using different grades of polyvinyl alcohol or copovidone in combination with indomethacin as the active pharmaceutical ingredient. The properties of the printed structures were assessed according to European Pharmacopoeia guidelines at different printing temperatures and laser scanning speeds in order to determine the suitable printing parameters.The results of the study indicate that the chemical properties of the polymers, such as dynamic viscosity, degree of hydrolyzation, and molecular weight, have significant impact on drug release and kinetics. Drug release rate and supersaturation can be modulated by selecting the appropriate polymer type. Furthermore, the physical properties of the dosage forms printed under the same settings are influenced by the selected polymer type, which determines the ideal manufacturing settings.This study demonstrates how the chemical properties of the polymer can determine the appropriate choice of manufacturing settings and the final properties of oral dosage forms produced using SLS.

Purpose of this work is to determine the average time to reach the boundaries, as well as to identify the strategy in the game between two players, controlling point movements on the finite square lattice using an independent choice of strategies. One player wants to survive, i. e., to stay within the interior of the square, as long as possible, while his opponent wants to reach the absorbing boundary. A game starts from the center of the square and every next movement of the point is determined by independent strategy choices made by the players. The value of the game is the survival time that is the number of steps before the absorption happens. In addition we present series of experiments involving both human players and an autonomous agent (bot) and analysis of the survival time probability distributions. Methods. In this work, methods of the theory of absorbing Markov chains were used to analyze strategies and absorption times, as well as the Monte Carlo method to simulate trajectories. Additionally, a large-scale field experiment was conducted using the developed mobile application. Results. The players’ strategies are experimentally obtained for the cases of playing against an autonomous agent (bot), as well as human players against each other. A comparison with optimal strategies and a random walk is made: the difference between the experimental strategies and the optimal ones is shown, however, the resulting strategies show a much better result of games than a simple random walk. In addition, especially long-running games do not show the Markovian property in case of the simulation corresponding strategies. Conclusion. The sampled histograms indicate that the game-driven walks are more complex than a random walk on a finite lattice but it can be reproduced with a Markov Chain model.

In the paper, the problem on an interface longitudinal shear crack located between two functionally graded wedge-shaped regions and emerging from their common vertex has been considered. The shear modules of the materials are quadratic functions of the polar angle. This kind of functional inhomogeneity made it possible to express all the components of the elastic field through a single harmonic function. Using the Mellin integral transform, the problem was reduced to the Wiener – Hopf scalar equation, for which an exact solution was obtained. The influence of gradients of elastic properties of materials and geometric parameters of the structure on the stress intensity factor was studied.

The research focused on chard plants grown in a vegetation chamber under irradiation of 600 μmol/(m2s-1) FAR and elevated CO2 concentration in the range of 1500-2000 ppm. The objective is to determine the feasibility of incorporating gaseous nitrogen-containing products of physicochemical mineralization of human exometabolites into the cycling process in relation to the conditions of bioregenerative systems of human life support. To replenish the Impoverished soil-like substrate with available forms of nitrogen, we introduced NH4NO3 into the irrigation solution. This can be obtained from NH3, which is a part of gaseous intrasystem mass exchange products. The incorporation of NH3 into the intrasystem cycle comprised three main steps. 1) Some of the NH3 was oxidized to nitrogen oxides, which dissolved in water and formed acid solutions; 2) Another part of the NH3 was barbotaged through a nitric acid solution to obtain NH4NO3; 3) The obtained ammonium salts were used as fertilizer and added to the irrigation solution for the cultivation of chard plants, which represent the phototrophic link in the bioregenerative life support system. The results clearly demonstrated that replenishing the available nitrogen forms in the Impoverished soil-like substrate to match the original substrate levels resulted in plant mass comparable to that of plants grown on freshly prepared substrate. The research results prove the potential of the developed technologies for involving dead-end gaseous nitrogen-containing waste from human activity in the intrasystem mass exchange of the life-support system.

The use of air curtains in livestock premises is aimed at limiting the amount of cold air entering through the open gate opening and heating it. Recommendations for selection and calculation methods for air curtains for cattle breeding farm premises are given, taking into account the influence of wind load. The proposed method makes it possible to calculate the thermal and energy parameters of air curtains, taking into account the variability of the climatic factors impact (wind speed and direction). The aerodynamic coefficients of the cowshed building, taking into account wind directions, were determined to calculate the amount of air entering through the gate opening protected by an air curtain. Formulas for calculating heat losses through an opening protected by an air curtain are given. The procedure for calculating the parameters is proposed and the requirements for air curtains for cattle breeding livestock premises are formulated.

The article considers the possibility of using thermoelectric dehumidifiers in microclimate systems for livestock premises. The advantages of dehumidifiers based on thermoelectric modules in comparison with compressor and adsorption units are shown. A block diagram of a thermoelectric dehumidifier designed to operate in agricultural production conditions is presented. The heat exchangers of the cold and hot circuits, as well as the electric fan, form a single structure and are installed in premises in which it is necessary to dehumidify the air. The dehumidification process in a thermoelectric unit is shown in the I-d diagram of humid air. A method for calculating a standard-sized range of thermoelectric units for air cooling (dehumidification) in agricultural premises has been developed. Provisions presented the method that allows determining the thermal and structural parameters of the main components when designing a thermoelectric unit.

In the paper, the problem of a semi-infinite antiplane interface crack located between two functionally graded wedge-shaped regions has been considered. The shear modules of the materials’ regions are quadratic functions of the polar angle. This kind of functional inhomogeneity made it possible to express all the components of the elastic field through a single harmonic function. Using the Mellin integral transform, the problem was reduced to the Wiener – Hopf scalar equation, for which an exact solution was obtained. The influence of gradients of elastic properties of materials on the stress intensity coefficient at the crack tip and the singularity value at the angular point of the structure was studied.

Objective. To determine type of cytomegalovirus (CMV) infection (reactivation of a virus strain that was present before transplantation or re-infection with another virus strain) in allogeneic hematopoietic stem cell recipients by sequencing. Materials and Methods. Clinical and laboratory data of 179 recipients of allogeneic hematopoietic stem cells collected from 2014 to 2018 were analyzed for CMV DNA in clinical specimens before and after transplantation. A total of 14 patients (28 samples) were included in the study. The CMV UL139 gene encoding viral glycoprotein was chosen for virus genotyping and sequence alignment. The primers complementary to its conservative sites were used. The resulting DNA sequence was analyzed using nucleotide BLAST software (https://blast.ncbi.nlm.nih.gov/Blast.cgi) and Genome compiler (https://designer.genomecompiler.com). The type of infection was determined by comparing DNA sequences before and after transplantation. Results. All enrolled patients were anti-CMV-positive prior to transplantation, which indicates the presence of CMV infection. Therefore, none of the patients had a primary infection as a result of transplantation. Of 14 patients, high percentage of sequence alignment (~100%) was observed in 8 patients. For the other 6 patients, substantial differences in sequences which indicate the different genotypes and the different type of infection were found. However, there was no statistically significant difference in the time to viral DNA appearance after transplantation in patients with re-infection and reactivation (p > 0.05), nor was there a statistically significant correlation between the type of infection (reactivation/re-infection) and the main diagnosis or transfusion load. Conclusions. Reactivation of the previously registered viral strain and re-infection with another viral strain were equally probable (8 vs. 6 cases). There were no associations between the main diagnosis and the type of infection (reactivation/re-infection) possibly due to a small sample size. Time to post-transplantation CMV DNA detection in blood was longer for re-infection (median of 69.5 days) compared to reactivation (median of 27 days), but this difference was also non-statistically significant. In addition, there was no significant contribution of blood transfusion burden to the type of CMV infection, which may suggest the donor blood is not a source of the different strains.

An analysis of scientific studies has been carried out, which presents thermoelectric technologies based on solar energy that can satisfy not only the need for electricity generation, but also contribute to energy saving and environmental protection. The results of theoretical and experimental studies on the development of power supply systems based on thermoelectric generators in combination with photovoltaic panels, solar concentrators and heat pipes are also presented, allowing us to conclude that the creation of solar thermoelectric generators is relevant. The authors have developed a design and presented a description of the power supply installation operation with a solar thermoelectric generator and heat pipes transmitting thermal energy from a solar concentrator through a solid-state thermal storage to a thermoelectric generator. Expressions are given for calculating the main thermal characteristics of the elements of the proposed installation with a solar thermoelectric generator (solar concentrator and solid-state thermal storage), as well as the efficiency factor and output electric power of the thermoelectric generator.

Objective. To identify mutations in UL97 gene associated with antiviral drug resistance in recipients of allogeneic hematopoietic stem cells transplants (allo-HSCT). Materials and Methods. A total of 9 HCMV DNA samples were studied. These samples were received from the blood of 8 allo-HSCT recipients who were infected with HCMV and undergoing treatment at NMRC of Hematology (Russia) over the period of 2016 to 2017. Sanger sequencing was used to find mutations. The sequenced part of the virus DNA was analyzed using nucleotide BLAST and Genome compiler. Mutations were identified using MRA program which compared the obtained nucleotide sequence with the reference sequence of UL97 gene from Merlin strain. Results. Rate of detection of viruses with mutations that may lead to drug resistance is relatively high – 3 of 8 patients. The following mutations were identified: C592G, C607F and C603W. The obtained data shows that the presence and characteristics of mutations affect the viral load and the time when HCMV DNA is identified in blood. Conclusions. Obtained data show that presence of mutations impacts the course infection, leading to higher viral load and longer persistence of viral DNA in blood samples. Identified mutations had different resistance factor, which also impacted on the pattern of infection.

An antiplane semi-infinite interface crack whose vertex coincides with the angular point of the material interface is considered. The exact solution of the problem is obtained using the Mellin integral transformation. Asymptotic formulas for stresses that may contain one or two singular terms are constructed near the crack tip. To analyze the crack growth, the Novozhilov V. V. force criterion of fracture was used. Based on the exact solution, the accuracy of calculating the angle of deflection of the crack and the breaking load, determined using asymptotics, is estimated. The dependence of these fracture characteristics from the composition parameters is investigated.

Due to the work of archaeologists and ethnographers, the funeral ceremony of the population having inhabited the middle and lower stretch of the Tara river (southern taiga zone of Western Siberia) at the end of the 17th–18th centuries has been quite extensively studied. However, little has been known thus far about its early period (late 16th — early 17th century) and the ethno-cultural identity of the people who buried the dead there. The discovery of coins during excavations conducted at Seitovo 4 — a burial ground located on a right bank of the Irtysh river on the southern outskirts of the eponymous village in Tarsky district, Omsk region — allowed the burial dates to be established. The above-mentioned coins of the Russian Tsardom (Moscow ‘denga’ minted in 1538–1561) belonged to the time of monetary reform under the rule of Ivan the Terrible. The data analysis revealed some specific features of the burial ceremony: grouping the graves in one complex; moving the body to one of the grave walls (usually northern); displacing the bones of the deceased on one side towards the spine; special actions when filling the grave pit; firing the burial pit and the area around it, etc. In addition, rare and unique things were found, including a forked arrowhead made from a copper plate with shaft remains; an article made from a copper plate in the form of a flat arrowhead with a single barb and a hole in the middle; a rectangular double-edged firesteel. At the same time, the features typical of burial grounds of the 17th–18th centuries widespread in the region were present: one burial under a mound in pits recessed into the ground; construction of ditches around the pit; traditional inventory (arrowheads, iron knives, axes, earrings, signet rings etc.); positioning the deceased on their back, with head to the north-north-west, etc. This shows that the complex belonged to their circle, constituting the earliest part of the funeral rite of the Tara Tatars' ancestors during the specified period. The analysis of written sources (first half of the 17th — first half of the 18th century) reveals that only Tatars, mostly the Ayali group, lived there at that time. Thus, assuming that the buried belonged to the specified group, conclusions can be drawn about the individual features of the burial rite.

A.L. Tikhomirov1, S.I. Sarsaniya2 1A.I. Evdokimov Moscow University of Medicine and Dentistry, Moscow, Russian Federation 2LLC “ANV”, Moscow, Russian Federation Iron deficiencies and iron deficiency anemia remain an important clinical issue. This article discusses high prevalence of iron deficiency anemia and its consequences in women. Classification of iron deficiencies, etiology, and pathogenesis of iron deficiency are addressed. A special section is devoted to iron metabolism. The article provides a brief summary of major proteins involved in iron metabolism and their role in maintaining iron homeostasis. Functional role of hepcidin (which plays a critical role in the regulation of extracellular iron levels) and iron recirculation are highlighted. The most promising areas of hepcidin application in hematology are addressed. Diagnostic criteria for iron deficiency anemia are uncovered. This approach which includes modern diagnostic and treatment modalities for iron deficiency additionally help protect women’s health even in common gynecological disorders and their complications associated with iron deficiency. Optimal dru g choice for the treatment and prevention of iron deficiency anemia is an important research area in modern clinical medicine. Keywords: iron deficiency anemia, iron, hepcidin, transferrin, erythropoietin, abnormal uterine bleeding, iron-containing biomolecules, complex iron medications. For citation: Tikhomirov A.L., Sarsaniya S.I. Iron deficiency anemia in women: solutions to the problem. Russian Journal of Woman and Child Health. 2020;3(1):–50. DOI: 10.32364/2618-8430-2020-3-1-44-50.

Incidence, severity, and risk factors for hemorrhagic cystitis (HC) were assessed in 267 patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). HC was diagnosed in 14.6% (39 patients) within 1-139 days after allo-HSCT (median duration – 39 days). Chemotherapy-related HC was diagnosed in 4 patients only. The majority (19/35) of patients developed late HC of viral aetiology. Median time from a day of HC diagnosis to clinical symptoms resolution was 25 days (range: 6 to 133 days). Using a multivariate analysis, allo-HSCT from mismatched unrelated/haploidentical donor was found to be a risk factor of HC (р=0.01). The analysis also showed that 82.1% of patients with HC received cyclophosphamide as a part of conditioning regimen or +3/+4 days after allo-HSCT.

Effective treatment for vulvovaginal candidiasis: case reports A.L. Tikhomirov1, S.I. Sarsaniya2 1A.I. Evdokimov Moscow University of Medicine and Dentistry, Moscow, Russian Federation 2LLC “S-Mariya”, Moscow, Russian Federation Treatment resistance remains a concern for gynecologists who face with vulvovaginal candidiasis. The signatures of Candida colpitis are high morbidity, long-term course, frequent recurrences, potential generalization with the involvement of other organs and systems, high resistance to antifungal agents, and challenges in treatment during pregnancy. Topical antifungal therapy is first-line option for vulvovaginal candidiasis due to its local effect in the immediate nidus of infection and rapid symptom relief (within few days of starting treatment). Adverse reactions are among the most common reasons to refuse treatment. In addition, subjective tolerability of adverse reactions and easy use are important since these factors improve treatment adherence and provide treatment success. Effective and appropriate antifungal agent should be administered. Natamycin, safe polyene antimycotic, meets these requirements. The paper reviews clinical cases illustrating treatment efficacy of vulvovaginal candidiasis with natamycin. Keywords: vulvovaginal candidiasis, antifungal resistance, fungicidal effect, safety, natamycin. For citation: Tikhomirov A.L., Sarsaniya S.I. Effective treatment for vulvovaginal candidiasis: case reports. Russian Journal of Woman and Child Health. 2019;2(2):155–159.

In the framework of the antiplane problem, a closed connection of two different isotropic wedges is considered, from the top of which a finite-length crack emerges at an arbitrary angle to the axis of symmetry of the structure. By reducing the problem to the Wiener-Hopf scalar equation, its exact solution is obtained. The dependence of the stress intensity factor (SIF) at the crack tip on the structural parameters is studied. The effects of increase and decrease of KIN in comparison with the case of a homogeneous medium are analyzed. It is shown that the stress asymptotics near the junction vertex can have one or two singular terms that determine both strong and weak singularities at this singular point.

Theoretical studies of the thermal state of heat storage elements with air channels of various shapes in the modes of charging and heat output of the electric thermal storage (ETS) are carried out. The mathematical model of heat exchange processes adapted to the operating modes of the ETS is presented. The change in the average heat transfer coefficient in the air channels in the conditions of natural and forced convection in the modes of charging and heat output ETS, and the heat flux density in the mode of charging of the ETS from a tubular electric heating element (TEH) for heat storage elements with channels of a slit and round shape are shown. The temperature distribution in heat storage elements made of chamotte and magnesite with slit-shaped (standard design) and round shape channels is obtained. As a result of the studies carried out, the temperature change and the dynamics of heat transfer in the air channels of heat storage elements made of various types of thermal storage material (TSM) in the modes of charging and heat output of the ETS were analyzed. The conclusion is made about the efficiency of using heat storage elements made of chamotte with round-shaped channels in the ETS.