MODELLING AND SIMULATION OF DYNAMIC PROCESSES OF PNEUMATIC LINES

The paper presents the simulation of dynamic processes of pneumatic lines using the program "SIMULINK" from the product " MatLab". Simulation is a process of forming, preparing and entering a mathematical model in a computational environment and obtaining the results of the calculations performed in this environment. The mathematical model of the pneumatic line to be simulated is according to previously presented equations. For the simulation of the dynamic processes, various real parameters of the dimensions and lengths of the pneumatic lines with the corresponding coefficients are introduced into the model. The simulation of the transient responses was carried out with stepwise variation and sinusoidal input signal supplied by the set point device and pneumatic line lengths of 1 m, 5 m and 10 m. The simulation output data were output to the interface in the form of graphs showing the dependence of the observed quantities, the input and output pressure through the pneumatic line, and the input and output flow rates. From the mathematical model and the experiments performed, it can be concluded that the transient responses in the simulations correspond to the dynamic processes of pneumatic lines of different lengths

MODELLING AND SIMULATION OF ELECTROPNEUMATIC POSITIONING SYSTEM INCLUDING THE LENGTH OF PNEUMATIC LINES

This paper presents a mathematical model of electropneumatic positioning system including the length of pneumatic lines for the determination of flow and pressure in unsteady operating modes. A simulation model is developed to study the dynamic processes in an electropneumatic positioning system. Simulation of the mathematical models of the screw compressor, proportional directional valve, pneumatic lines, pneumatic cylinder and PID controller were designed in “MatLab Simulink”. The simulation models of the transients in the electropneumatic positioning system at different line lengths from 1m and 10m with stepwise variation of the input setpoint are simulated developed. Graphical comparison is made of the obtained experimental results and simulation model influence of the pneumatic line length on the dynamics of the electropneumatic positioning system are made

LINFOMAS NO-HODGKIN B DE ALTO GRADO: RECLASIFICACIÓN SEGÚN CRITERIOS OMS 2016 Y SU VALOR COMO FACTOR PRONÓSTICO

INTRODUCCIÓN La clasificación de los tumores de los tejidos hematopoyéticos y linfoides de la OMS del año 2016 define una nueva categoría, el Linfoma No-Hodgkin B de alto grado (LBAG), que incluye a los LBAG, NOS y los LBAG con translocación de MYC, BCL2 y/o BCL6, también denominados linfomas doble/triple hit (LDH/TH). Estos linfomas representan 1-2% de los linfomas no-Hodgkin y una parte importante de los linfomas B difusos de célula grande (LBDCG) refractarios a la terapia con R-CHOP. Este grupo de linfomas es equiparable a los linfomas B inclasificables, con rasgos intermedios entre LBDCG y linfoma de Burkitt (LBI) en la clasificación la OMS del año 2008. Durante la última década, los LBAG DH/TH han llamado la atención de los hematólogos y los oncólogos, debido a su significativo peorpronóstico. OBJETIVOS El presente trabajo tiene como finalidad, presentar la base teórica de la incorporación de este nuevo grupo de neoplasias, resumir sus criterios diagnósticos actuales y explicar la importancia de su separación de los LBDCG. Ademas se expondrá la metodología de un estudio que va a comprobar la reproducibilidad de estos criterios en la casuística de los HCU Lozano Blesa y HU Miguel Servet, y su repercusión en el pronóstico de los pacientes afectados por este tipo de neoplasia. MATERIALES Y METODOS En primer lugar se realizará una búsqueda bibliográfica exhaustiva del conocimiento acumulado sobre esta entidad en los bases de datos PubMed y EMBASE. A base de la información recopilada se propondrá la realización un estudio observacional retrospectivo en pacientes diagnosticados de LBDG en los hospitales HCU Lozano Blesa y del HU Miguel Servet entre enero de 2005 hasta diciembre de 2015. Tras la reevaluación y confirmación de los diagnósticos, se aplicarán los nuevos criterios, utilizando técnicas inmunohistoquímicas y citogenéticas (FISH) para separar los casos de LDH/TH de los LBDCG. A continuación se analizarán la supervivencia global y la supervivencia libre de progresión entre ambos grupos y se comprobará el papel del perfil de LDH/TH como factor pronóstico. CONCLUSIÓN Los LDH/TH son linfomas agresivos y refractarios al tratamiento estandar. Su diagnóstico correcto es de gran importancia para la identificación de estos pacientes de alto riesgo y su inclusión en estudios clínicos con el fin de encontrar esquemas terapéuticos más efectivos.<br /

Specifics in the operating modes of thermosyphon air heater of steam generators №1 and №2 in TPP "Republika" at fuel switch from coal to natural gas

A fuel switch is motivated both by the necessity of increasing energy efficiency and the compliance with the ever-stricter regulations regarding the release of harmful emissions in the environment. In this paper a thorough financial and energy analysis on the fuel switch from coal to natural gas is carried out, in particular with respect to waste heat recovery systems (two phase thermosyphons). As a result of the calculation of the heat transfer coefficients for both fuels, it is established that the system running on natural gas has a lower value, due to the lower air velocity, caused in turn by the lower requirement for excess air. The heat transfer coefficients of the evaporation and condensation zones respectively are established hfgas=104.9 И hair=84.9 (W/m2.K) for coal and hfgas И hair =84.7 (W/m2.K) respectively for gas. A numerical study is also carried out and a methodology for the analysis of the efficiency of two phase thermosyphons with complex geometry is presented

<em>Helicobacter pylori</em> Infection

Helicobacter pylori (H. pylori) is a Gram-negative spiral bacterium commonly found in the stomach. Major part of the world’s population is infected with H. pylori and is at increased risk of severe gastritis, peptic ulcer disease, and gastric cancer. Most studied virulence factors of the bacterium are the cytotoxin-associated gene (CagA) and the vacuolating cytotoxin A (VacA). The H. pylori infection is diagnosed by invasive (histological examination, culture, and rapid urease test, which require endoscopy and biopsy) and noninvasive methods (serology, urea breath test, and stool antigen test). H. pylori eradication is preferred for a long-term prevention of complications. Current treatments consist of antibiotics and adequate PPI dose and can be divided into two strands—with or without bismuth. Achieving an eradication rate of >90% is an indicator for effective treatment. Due to the increasing levels of antibiotic resistance, the standard triple therapy is largely replaced with a quadruple therapy, especially in countries with high resistance rates. Antimicrobial susceptibility testing should be performed after the second-line treatment failure, leading to an individualized patient treatment. Clear explanations and patients’ compliance are of great importance for a better outcome

Current View on Autoimmune Gastritis

Autoimmune gastritis (AIG) is a chronic inflammatory disease of the gastric corpus and fundus. Although still unclear, genetic and environmental factors, antigenic mimicry or cross-reactivity are proposed pathogenic mechanisms. Parietal cells destruction results in loss of intrinsic factor and increased gastric pH due to hypochlorhydria and G-cell proliferation. Furthermore, atrophy, intestinal, pancreatic and spasmolytic polypeptide-expressing metaplasia are observed. AIG is underdiagnosed, however, proper diagnostic approach, including endoscopic, serological and histopathological assessment, is required. Gastroscopy with corpus and fundus biopsies is a gold standard. A serological combination of anti-parietal cell antibodies, intrinsic factor antibody, anti-Helicobacter pylori IgG, gastrin, pepsinogen I and pepsinogen I/II ratio improves the diagnostic sensitivity and specificity and allows atrophy level prediction. AIG might manifest with multifactorial iron deficiency anemia, vitamin B12 deficiency (pernicious anemia), neurological and neuropsychiatric conditions, small intestinal bacterial overgrowth and gastrointestinal infections. AIG association with other autoimmune diseases is well-established. Gastric cancer and gastric carcinoid are neoplastic transformations of a continuous chronic inflammation. Patients with AIG should be carefully monitored as no specific AIG therapy is available and disease complication could be fatal

Numerical simulation of nitrogen oxide formation in dust furnaces

Even though natural sources of air pollution account for over 50&nbsp;% of sulphur compounds, 93&nbsp;% of nitrogen oxide which are the most dangerous artificial anthropogenic sources of air pollution and primarily associated with the combustion of fossil fuel. Coal-fired thermal power plants and industrial fuel-burning plants that emit large quantities of nitrogen oxides (NО and NО2), solids (ash, dust, soot), as well as carbon oxides, aldehydes, organic acids into the atmosphere pollute the environment in majority. In the present work, a mathematical model and a scheme for calculating the formation of nitrogen oxide has been developed. Also, the dependence of the rate of release of fuel nitrogen from coal particles at the initial stage of gasification and content of volatiles has been obtained. The main regularities of the formation of NOx at the initial section of the flame in the ignition zone of the swirl burner flame during the combustion of Ekibastuz coal have been revealed. Modern environmental requirements for the modernization of existing and the creation of new heat and power facilities determine the exceptional relevance of the development of effective methods and constructions to reduce emissions of nitrogen oxides, sulfur oxides and ash to 200,&nbsp;300, and 100&nbsp;mg/nm3 at a=1.4. The dust consumption in all experiments was kept constant and amounted to 0.042&nbsp;g/s, as well as with the results of calculating the thermal decomposition of the Ekibastuz coal dust, the recombination of atomic nitrogen into nitrogen molecules, and the kinetics of the formation of fuel nitric oxide. It was found that despite the presence of oxygen in Ekibastuz coal for gases Odaf=11.8&nbsp;% in an inert atmosphere, nitrogen oxides are not forme

Gastric Microbiota: Between Health and Disease

The etiologic link between H. pylori infection and gastric chronic inflammation and related complications has been well established, but pathogenic pathways are still widely discussed and not sufficiently clear. The introduction of culture-independent molecular techniques has allowed better understanding of the gastric microbiota and has revealed that, when present, H. pylori represents the main colonizer but is part of a far more complex and dynamic microbiota than previously thought. This conceptual shift has made way for new pathogenic theories, focused on the interrelations between H. pylori and other gastric microbiota. Main factors that affect the gastric microbiota are gastric acidity, inflammation, and environmental factors, such as diet and drugs. Previous studies have made progress in explaining the complex interactions between gastric microorganisms in healthy individuals and their role in the development of related gastroduodenal (peptic ulcers and gastric cancer (GC)) and extraintestinal diseases, but more scientific proof is needed. This review presents current knowledge on gastric microbiota and its role in health and in the development of gastroduodenal diseases

STUDY OF THE ENERGY POTENTIAL OF RENEWABLE ENERGY SOURCES IN THE REGION OF GABROVO FOR USE IN HYBRID WIND-PHOTOVOLTAIC STAND-ALONE SYSTEM

This paper presents the measurements conducted for two periods (winter and summer) in the region of Gabrovo, Bulgaria for solar radiation and wind conditions using the digital measuring equipment. The aim is to evaluate  and predict the possible production of electricity from already installed low power hybrid system. The conclusion is that a combination of a wind generator and a photovoltaic system in the hybrid system for independent power supply has a good economic effect and allows fuller use of energy from renewable sources.This paper presents the measurements conducted for two periods (winter and summer) in the region of Gabrovo, Bulgaria for solar radiation and wind conditions using the digital measuring equipment. The aim is to evaluate  and predict the possible production of electricity from already installed low power hybrid system. The conclusion is that a combination of a wind generator and a photovoltaic system in the hybrid system for independent power supply has a good economic effect and allows fuller use of energy from renewable sources