Indices of dental health in children and adolescents from Saratov and the Saratov region

<p>Objective: to determine the level of dental health in children and adolescents living in the Saratov region. Material and methods. To assess the intensity and prevalence of major dental diseases 1510 patients have been examined by the method recommended by the WHO Collaborating Centre in Russia. Results. A comparative analysis of caries and occurrence of different types of teeth-maxillary anomalies among children aged from 3 to 18 years. Conclusion. The epidemiology of major dental diseases in the Saratov region is characterized by the significant spread of caries from 70 to 94,6% in the different age groups. The proportion of people with malocclusion among the surveyed reaches 46,6%.</p

Intelligent Control, Correction, and Adaptability of Output Parameters of Vehicles’ Intake System

© 2020, Springer Nature Switzerland AG. Today, the modern motor industry is developing in the direction of significant intellectualization, automation, and robotics at the system operation. It provides for the creation of a comprehensive system of system control algorithms. However, when the technical condition of individual electronic components varies, the control algorithms can significantly change. Thus, correction and adaptation of the operation algorithms to the changing technical condition of the vehicle systems is necessary for a further qualitative object operation. Thus, failures of mass airflow sensors and idle air control valves comprise 14 and 12%, respectively, of the number of failures of all the elements of the microprocessor-based engine control system. A failure of these components leads to a serious change in fuel consumption and exhaust toxicity. We developed an experimental research procedure to elaborate the modes of correction and adaptation to the changing technical condition of these elements of the car electronics. It lies in the formation of stress test actions consisting in the cutout of the nth number of cylinders and individual operating cycles and subsequent loading of the kth number of cylinders. As a result of experimental studies, we built diagrams of the dependencies of the said control parameters on the cylinder load. We analyzed the diagrams, based on which we determined the inflection points corresponding to the prelimit and limit change in the technical condition of the mass airflow sensors and idle air control valves. The developed method of stress test actions allows us to avoid purchasing expensive load banks

Modernization of Chamber Furnace Electric Equipment

© 2020 IEEE. As part of the electrical equipment modernization, we propose a continuous temperature control system for a chamber resistance furnace. A furnace model is developed in the VisSim software package, which takes into account the heterogeneity of the furnace as a control object and includes 3 heat transfer circuits. System delays caused mainly by the delay of the thermocouple are also taken into account. Calculations of the accuracy of temperature stabilization for relay and digital controllers are performed. The relay control method shows large temperature fluctuations on the heating element, which significantly reduces the service life of the heating elements. The implementation of pulse control using a PID controller based on a temperature controller allows increasing the accuracy of temperature maintenance in all modes to a level of ± 0.2 ° C

Diagnostics of the fuel supply system of auto ICEs by the test method

According to scientific studies dealing with the statistics of ICE (internal combustion engine) failures, most of them are registered in the ignition system (25%) and the power system (35%). The operable state of the ICE fuel system can be maintained by developing effective testing methods. For the purpose of theoretical research, a DBD-4 testing device was designed in the methodological part of the research. The use of the developed methodologies and instrumentation allowed carrying out experimental studies to diagnose the operability of the fuel supply system. Analyzing the obtained experimental data, it can be affirmed that: there is a stable relationship between the change in the ICE crankshaft speed and the change in the injection duration of the electromagnetic injector; the degree of wear of the electric fuel pump (EFP) is determined by the shift of the stable value of the crankshaft speed to the zone of low speed values at the same injection durations. The data obtained after testing the EFP allows planning a further algorithm of actions to maintain the operability of the fuel supply system

Diagnostics of the fuel supply system of auto ICEs by the test method

According to scientific studies dealing with the statistics of ICE (internal combustion engine) failures, most of them are registered in the ignition system (25%) and the power system (35%). The operable state of the ICE fuel system can be maintained by developing effective testing methods. For the purpose of theoretical research, a DBD-4 testing device was designed in the methodological part of the research. The use of the developed methodologies and instrumentation allowed carrying out experimental studies to diagnose the operability of the fuel supply system. Analyzing the obtained experimental data, it can be affirmed that: there is a stable relationship between the change in the ICE crankshaft speed and the change in the injection duration of the electromagnetic injector; the degree of wear of the electric fuel pump (EFP) is determined by the shift of the stable value of the crankshaft speed to the zone of low speed values at the same injection durations. The data obtained after testing the EFP allows planning a further algorithm of actions to maintain the operability of the fuel supply system

Cellular composition and ultrastructure of periapical granulation tissue in primary and secondary chronic periodontitis

Background. There are no complete data on the occurrence of bacteria in the outbreak of chronic inflammation a consequence of their high virulence, or the result of a defect of local mechanisms of immune protection. To answer these questions, as well as to evaluate the nature, severity changes periapical tissues of the tooth and the activity of the inflammatory process in the apex of the tooth root is possible only during the morphological study of biopsy material. Objective. The aim of this work was to study the cellular composition and ultrastructural features of the granulation tissue formed during the current the primary and secondary apical periodontitis. Methods. There were included in the histological examination of the teeth 78, who underwent resection of the apex, followed by a fence of histological material. For ultrastructural studies of granuloma periodontal tissue samples were fixed with 2.5% glutaraldehyde solution, material embedded in Epon-812 («SPI-Pon ™ 812 Epoxy Embedding Kit», USA). The study was conducted using a transmission electron microscopy. Results. In the development of destructive periodontal inflammation are actively involved both specific and non-specific mechanisms of immunity. Conclusion. In primary periodontitis granulation tissue contains a moderate amount of white blood cells of various types, as well as single macrophages and plasma cells with reduced functional activity. In secondary periodontitis granuloma contains numerous mononuclear macrophages, plasma cells and giant multinucleated cells with increased activity, which corresponds to the morphological picture of the formation of immune granulomas. Citation: Gritsenko PI, Petruk NS, Samoylenko AV, Tverdokhleb IV. [Cellular composition and ultrastructure of periapical granulation tissue in primary and secondary chronic periodontitis]. Morphologia. 2014;8(2):14-9. Russian

Information-analytical aspects of the reception organisation of powder microcomposites on an iron basis

The basic stages of a complex development direction of a science and practice of powder metallurgy as method of information-analytical representation of its basic aspects are presented. The basic algorithm of carrying out of operations and the scheme of the decision of tasks in view on object with some number of unknown factors is given. Ways of the further perfection of the presented technology of powder metallurgy and nanocomposite materials are planned

Gut as a target for cadmium toxicity

The primary objective of the present study was to review the impact of Cd exposure on gut microbiota and intestinal physiology, as well as to estimate whether gut may be considered as the target for Cd toxicity. The review is based on literature search in available databases. The existing data demonstrate that the impact of Cd on gut physiology is two-sided. First, Cd exposure induces a significant alteration of bacterial populations and their relative abundance in gut (increased Bacteroidetes-to-Firmicutes ratio), accompanied by increased lipopolysaccharide (LPS) production, reflecting changed metabolic activity of the intestinal microbiome. Second, in intestinal wall Cd exposure induces inflammatory response and cell damage including disruption of tight junctions, ultimately leading to increased gut permeability. Together with increased LPS production, impaired barrier function causes endotoxinemia and systemic inflammation. Hypothetically, Cd-induced increase gut permeability may also result in increased bacterial translocation. On the one hand, bacteriolysis may be associated with aggravation of endotoxemia. At the same time, together with Cd-induced impairment of macrophage inflammatory response, increased bacterial translocation may result in increased susceptibility to infections. Such a supposition is generally in agreement with the finding of higher susceptibility of Cd-exposed mice to infections. The changed microbiome metabolic activity and LPS-induced systemic inflammation may have a significant impact on target organs. The efficiency of probiotics in at least partial prevention of the local (intestinal) and systemic toxic effects of cadmium confirms the role of altered gut physiology in Cd toxicity. Therefore, probiotic treatment may be considered as the one of the strategies for prevention of Cd toxicity in parallel with chelation, antioxidant, and anti-inflammatory therapy. It is hypothesized that increased gut permeability, altered gut microbiota, endotoxinemia, and impaired inflammatory response may at least partially mediate the toxic effects of Cd exposure. © 2018 Elsevier Lt

Selenium and autism spectrum disorder

Autism spectrum disorder (ASD) represents a complex neurodevelopmental disorder, being associated with various metabolic abnormalities. Micronutrients, including selenium (Se), are frequently used for ASD management. However, their efficiency remains unclear. Moreover, data on the role of Se metabolism in ASD are insufficient and contradictory. Therefore, the objective of this chapter is to review the existing data on Se status of children with ASD. Current data demonstrate that Se intake varies in children with ASD from low to high values in comparison to the daily recommendations. Similarly, data on Se status in ASD are also contradictory. Of 16 studies reviewed, eight indicate decreased Se levels in samples from autistic children, whereas six demonstrate opposite changes. Correspondingly, two recent meta-analyses failed to reveal any significant association between Se status and ASD. The activity of GPX in children with ASD is also highly variable from study to study. The observed difference in Se level in ASD patients may be related to different substrates used, as well as to specific features of the studied populations. However, the existing studies indicate involvement of Se imbalance in metabolic/psychometabolic disturbances in ASD. The mechanisms of a proposed Se neuroprotective effect in ASD may involve inhibition of oxidative stress, neuroinflammation, and microglia activation. In addition, synaptic dysfunction and gut-brain axis disturbances might be modified. However, further studies are required to highlight the mechanisms of the potential neuroprotective effects of Se in ASD as well as its efficiency in clinical trials. © Springer International Publishing AG, part of Springer Nature 2018