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2022 ◽  
Vol 19 (1) ◽  
pp. 73-76
Author(s):  
Madhu Aryal

Introduction: Cardiomyopathy is the disorder of the heart muscles which can be dilated, hypertrophic or restrictive type. Dilated cardiomyopathy is caused by genetic and non-genetic causes but many of the causes are still not known. Echocardiography is an important imaging technique to diagnose and manage dilated cardiomyopathy. Aims: This study aims to assess the clinical and echocardiographic findings among patients with dilated cardiomyopathy. Methods: This is a cross-sectional, observational study conducted in Nepalgunj Medical College from January 2021 to June 2021. A total of 61 patients with dilated Cardiomyopathy were enrolled after obtaining written informed consent. Clinical examination and echocardiographic findings were recorded and data analysis was done using Statistical Package for Social Sciences. Results: The participants included 31 men and 30 women with dilated cardiomyopathy. The mean age of the participants was 58.49 + 15.46 years. The most common complaint was shortness of breath 84.5% and the most common clinical presentation was bilateral basal crepitation 98.4%. The patients mostly had diastolic left ventricle internal diameter of 5.5-6 cm and ejection fraction of 21-30%. Mitral regurgitation was observed among most 58(95.1%) of the patients. Conclusion: This study concludes that shortness of breath and bilateral basal crepitation are the most common presentation. Left ventricle dilation, reduced ejection fraction and mitral regurgitation are seen among majority of the patients.


Irriga ◽  
2022 ◽  
Vol 1 (4) ◽  
pp. 739-747
Author(s):  
Madson Rafael Barbalho da Silva ◽  
Lívia Maria Cavalcante Silva ◽  
Ana Cláudia Davino dos Santos ◽  
Fabiano Simplicio Bezerra ◽  
Caio Sérgio Pereira de Araújo ◽  
...  

AVALIAÇÃO DE DESEMPENHO DO MICROASPERSOR EM LINHA LATERAL E SIMULAÇÃO MATEMÁTICA DE SEU GRADIENTE DE ENERGIA     MADSON RAFAEL BARBALHO DA SILVA1; LÍVIA MARIA CAVALCANTE SILVA1; ANA CLÁUDIA DAVINO DOS SANTOS1; FABIANO SIMPLICIO BEZERRA1; CAIO SÉRGIO PEREIRA DE ARAÚJO1 E MANASSÉS MESQUITA DA SILVA1   1 Departamento de Engenharia Agrícola, Universidade Federal Rural de Pernambuco, Dom Manuel de Medeiros, s/n, Dois Irmãos, 52171-900, Recife, Pernambuco, Brasil. E-mail:[email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected].     1 RESUMO   Objetivou-se avaliar o desempenho do microaspersor Agropolo modelo MC20 em diferentes condições hidráulicas, gerando informações para um melhor dimensionamento de sistemas de microirrigação e manejo da água em áreas irrigadas. A condução do projeto hidráulico para simulação do gradiente de energia em linhas laterais, considerou-se informações determinadas através da escolha de componentes do projeto. Foram extraídos do catálogo comercial do fabricante os pares de valores referentes a vazão e a pressão e, a partir destes, gerou-se a curva vazão-pressão, onde a simulação foi feita pelo Método Algébrico - Christiansen (MA) e Método Iterativo (SBS) – Back-Step. Para ambos métodos o microaspersor se comportou de maneira semelhante, quando submetido a condições sugeridas pelo fabricante, num espaçamento entre emissores de 5,2 m, usando tubos de polietilenos de diâmetro interno de 13 mm e uma pressão de serviço de 20 mca, admitindo uma variação de 10% da pressão. Foram calculados os coeficientes de uniformidade de pressão (CUp) e de vazão (CUq), ambos com valores superiores à 95%, demonstrando a excelência no desempenho do emissor.   Palavras-chave: hidráulica, modelagem matemática, coeficiente de descarga.     SILVA, M. R. B.; SILVA, L. M. C.; SANTOS, A. C. D.; BEZERRA, F. S.; ARAUJO, C. S. P.; SILVA, M. M. PERFORMANCE EVALUATION OF THE SIDE LINE MICROSPARENT AND MATHEMATICAL SIMULATION OF ITS ENERGY GRADIENT     2 ABSTRACT   The objective was to evaluate the performance of the Agropolo model MC20 microsprinkler under different hydraulic conditions, generating information for a better design of micro-irrigation systems and water management in irrigated areas. The conduction of the hydraulic project to simulate the energy gradient in lateral lines, considered information determined through the choice of project components. The pairs of values ​​referring to flow and pressure were extracted from the manufacturer's commercial catalog and, from these, the flow-pressure curve was generated, where the simulation was performed using the Algebraic Method - Christiansen (MA) and Iterative Method (SBS) – Back-Step. For both methods, the microsprinkler behaved similarly, when subjected to conditions suggested by the manufacturer, in a spacing between emitters of 5.2 m, using polyethylene tubes with an internal diameter of 13 mm and a working pressure of 20 mca, admitting a 10% pressure variation. The uniformity of pressure (CUp) and flow (CUq) coefficients were calculated, both with values ​​above 95%, demonstrating the excellence in the performance of the emitter.   Keywords: hydraulic, mathematical modeling, discharge coefficient.


2021 ◽  
Vol 9 (12) ◽  
pp. 516-524
Author(s):  
Nawaf M.O.S Ali ◽  
◽  
Mohammad H.AAA Alsaffar ◽  

Over the past two decades, the field of vascular surgery has experienced tremendous advances in technique and technology. After the description of vascular anastomosis by Dr. Alexis Carrel almost one hundred years ago, the subsequent years were slowly crowned by the differentiation of general and vascular surgeons (Friedman 2016). Notably, surgeons were able to distinguish themselves by developing and acquiring techniques that are specific to operations in vascular surgery. This type of surgery involves diseases associated with the vascular system, which specifically includes the arteries, veins, and the lymphatic structure. Thus, vascular surgery provides treatment for diseases associated with the veins and arteries and is used in cases where less invasive methods cannot be incorporated (Reis and Roever 2017). Importantly, vascular diseases arise from damaged vessels or the presence of inflammations or blood clots leading to the occurrence of illnesses like peripheral vascular disease or peripheral arterial disease (PAD) that is occlusive in nature. Notably, vascular occlusion can be defined as the blockage of blood vessels due to the growth of an abnormality or the accumulation of fat or calcium in the inner lining of the venous structure. Occlusion is a common characteristic of PAD where the diameter of the blood vessels narrows considerably (Rotzinger, Lu, Kawkabani, Marques-Vidal, Fetz and Qanadli 2020). Another good example of peripheral vascular occlusion arises from atherosclerosis. This is an occlusive disease where the arteries harden due to fat or calcium, leading to the narrowing of the internal diameter of the vessels (Rotzinger et al. 2020). Over time, this diameter narrows greatly resulting in the formation of clots that restrict the supply of blood to the entire area past the blockage, leading to the development of PVD/PAD.


Actuators ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 9
Author(s):  
Seongkyu Chang ◽  
Sung Gook Cho

This study developed a nonlinear behavior prediction model for elasto-plastic steel coil dampers (SCDs) using artificial neural networks (ANN). To train the ANN, first, the input and output data of the behavior of the elasto-plastic SCD was prepared. This study utilized the design parameters and load–displacement curves of the SCD to train the ANN. The elasto-plastic load–displacement curve of the SCD was obtained from simulation results using an ANSYS workbench. The design parameters (wire diameter, internal diameter, number of active windings, yield strength) of the SCD were defined as the input patterns, while the yield deformation, first stiffness, and second stiffness were output patterns. During learning of the neural network model, 60 datasets of the SCD were used as the learning pattern, and the remaining 21 were used to verify the model. Although this study used a small number of learning patterns, the ANN predicted accurate results for yield displacement, first stiffness, and second stiffness. In this study, the ANN was found to perform very well, predicting the nonlinear response of the SCD, compared with the values obtained from a finite element analysis program.


Author(s):  
Ihor Babyn

The aim of the research is to develop a mathematical model of the hydraulic injector of the flushing system and to determine the design parameters of the injector that ensure the destruction of milk deposits on the surface of the elements of the milking parlor of complex geometric configuration. A physical and mathematical model of the process of operation of the hydraulic injector of the flushing system has been developed, which creates a jet of detergent solution of directed action for cleaning the inner surfaces of the milk system. As a result of theoretical researches dependences of radius of a site of blow of a stream Ra and its pressure on a surface of milk pipe system pa on internal diameter of a nozzle dn, distance to it Hj at various values of pressure on an exit of a nozzle pn are received. Using the element base of the milking equipment, a low-pressure centrifugal type milk pump (≈ 3 atm) was selected as the basic hydraulic pressure generator. The dn = 2.1 mm, Hj = 16.6 cm, Ra = 23.6 mm. As a result of experimental studies of the hydroinjector of the flushing system, the dependences of the value of the force of the cleaning solution jet on the surface Fa and the degree of cleaning of the surface from milk deposits after flushing χ from the nozzle outlet pressure pn, the distance between the nozzle and the surface Hj and its inner diameter dn. Visual and statistical (according to Fisher's criterion F = 1,68 <F0,05 (6,30) = 2,42 and correlation coefficient R = 0,97) comparison of theoretical and experimental results of researches allows to assert about adequacy and logic of the received dependences of force of action. jet of detergent solution on the surface of Fa from the research factors in the appropriate range of their values. Pn = 500 kPa, dn = 0.00175 m, Hj = 0.191 m were determined as rational design and mode parameters of the hydroinjector from the condition of the maximum degree of cleaning of the surface from milk deposits after washing χ = 40.1%.


2021 ◽  
Vol 22 (24) ◽  
pp. 13557
Author(s):  
Mariella Rosalia ◽  
Priusha Ravipati ◽  
Pietro Grisoli ◽  
Rossella Dorati ◽  
Ida Genta ◽  
...  

Peripheral artery occlusive disease is an emerging cardiovascular disease characterized by the blockage of blood vessels in the limbs and is associated with dysfunction, gangrene, amputation, and a high mortality risk. Possible treatments involve by-pass surgery using autologous vessel grafts, because of the lack of suitable synthetic small-diameter vascular prosthesis. One to five percent of patients experience vascular graft infection, with a high risk of haemorrhage, spreading of the infection, amputation and even death. In this work, an infection-proof vascular graft prototype was designed and manufactured by electrospinning 12.5% w/v poly-L-lactic-co-glycolic acid solution in 75% v/v dichloromethane, 23.8% v/v dimethylformamide and 1.2% v/v water, loaded with 0.2% w/wPLGA. Polymer and tobramycin concentrations were selected after viscosity and surface tension and after HPLC-UV encapsulation efficiency (EE%) evaluation, respectively. The final drug-loaded prototype had an EE% of 95.58% ± 3.14%, with smooth fibres in the nanometer range and good porosity; graft wall thickness was 291 ± 20.82 μm and its internal diameter was 2.61 ± 0.05 mm. The graft’s antimicrobic activity evaluation through time-kill assays demonstrated a significant and strong antibacterial activity over 5 days against Staphylococcus aureus and Escherichia coli. An indirect cell viability assay on Normal Human Dermal Fibroblasts (NHDF) confirmed the cytocompatibility of the grafts.


2021 ◽  
pp. 1-29
Author(s):  
Yi Ran Lu ◽  
Deepak Pudasainee ◽  
Md Khan ◽  
Rajender Gupta ◽  
Petr Nikrityuk

Abstract This work is devoted to experimental and numerical studies of volt-ampere characteristics of a fixed bed heated by the Joule heating. The main feature of this type of fixed bed is internal heat generation using the Joule heat. The application is to provide the heat to chemically reacting gases flowing through the bed reactor. To validate our model a cylindrical packed bed is considered with a height of 11 cm and an internal diameter of 4.8 cm. This bed is filled with 86 balls made of carbon steel with a diameter of 1/2 inches (1.27 cm). For numerical simulation, open-source DEM software is used to generate the cylindrical packed bed. Electric field distribution is calculated using a new particle-unresolved DEM-based model coupled with a discrete heat transfer model to account for the temperature dependency of the electrical conductivity of steel particles. The results of the simulation were found to be in good agreement with experimental data.


Author(s):  
Hend Elzefzafy

The advantages of fiber-reinforced polymer (FRP) composite material have attracted architectural engineers as alternative construction materials. FRP materials are noncorrosive, lightweight, exhibit high tensile strength, and stiffness, are easily fabricated and constructed. For architectural applications, FRP materials are fabricated using a polymer matrix, such as epoxy, vinyl ester, or polyester, and reinforced with various grades of carbon, glass, and/or aramid fibers. In this study, FRP coupons have been tested under axial tensile load to evaluate the strength of these materials for architectural application. Coupon specimens were cut from two different types of glass-FRP (GFRP) tubes namely: Type I and II, the two types had constant internal diameter equal to 152 mm. The GFRP tubes Type I consist of six layers with (±60°) fibers angles oriented mainly in the hoop direction with respect to the longitudinal axis of the tubes, the total thickness is 2.65 mm. While GFRP tubes I consist of fourteen layers with different fibers angles (±65, ±45, ±65) and the total thickness are 6.4 mm. The test results were presented and discussed. The strength of the coupon showed an acceptable level to be used for architectural application. Some of the FRP composites successful applications are briefly presented and discussed to provide the appropriate background for the application of FRP composites in architectural engineering. The promising results presented for the GFRP materials represent a further step toward architectural application.


2021 ◽  
pp. 25-30
Author(s):  
Евгений Евгеньевич Простов

В статье представлены результаты экспериментальных исследований истечения пропана в различных направлениях в закрытом помещении. Рассматривался случай, когда источник истечения находился в багажнике автомобиля - имитация нахождения автомобиля с газомоторным топливом на станции технического обслуживания. Целью эксперимента являлось изучение механизма пространственного распространения газа в закрытом помещении для валидации математических моделей, используемых в программном комплексе ANSYS Fluent при моделировании поступления пропана в закрытое помещение. This scientific work describes a test conducted in a multidisciplinary test box on the testing training ground of the Orenburg branch of the All-Russian Research Institute for Fire Protection of EMERCOM of Russia. For the experiment there was built a room to simulate a service station (or parking box) for two cars. The frame was made of wooden bars and a plastic film was used to isolate the internal volume. The experimental installation consisted of a gas source with an internal diameter of 5 mm, located in the center of the room, and a system for gas supply and registration of experimental data from six gas analyzers SGOES-2 with a measurement range of pre-explosive concentrations from 0 to 100% of the lower concentration limit of flame propagation (NKPR) or a volume fraction from 0 to 1.7% with absolute ± 5% NKPR (in the range from 0 to 50% NKPR) and relative ± 10% NKPR (in the range from 50 to 100% NKPR) errors. In the center of the experimental room there was placed a car with the gas source in the trunk. All openings to the interior were insulated with plastic film and mounting foam. Natural cracks were left between the trunk lid and the body. The gas source is located in the trunk of the car and is directed towards the wide part of the trunk at an angle of 30 degrees relative to the floor (simulating the location of the gas cylinder used in cars). The gas analyzers were located along the wall, where the outflow is directed along the perimeter of the trunk, and one gas analyzer was located directly in the trunk behind the gas analyzer to control gas contamination. Propane has been released into the trunk with a constant flow rate of 2.8 m/h for 5 minutes. There were 8 test starts of the gas supply system (the flow vertically down), and then there were carried out 3 experiments per 3 series of tests in each. The purpose of the test was to study the mechanism of spatial gas propagation in an confined space for validation of mathematical models used in the ANSYS Fluent software package when modeling the propane intake into the confined space


Author(s):  
INDAH SUASANI WAHYUNI ◽  
IRNA SUFIAWATI ◽  
WIPAWEE NITTAYANANTA ◽  
JUTTI LEVITA

Objective: Kaempferia galanga L. rhizome (KGR), has been empirically used in Indonesia, particularly by Javanese, to cure inflammation. KGR contains various secondary metabolites which explain its pharmacology activities, among them is ethyl p-methoxycinnamate (EPMC). However, due to the different seasons of our country, the yield of extraction is often unalike. In this work, we determined the percentage of yield (w/w), the water content (thermogravimetric method), and the concentration of EPMC in the Ethanol extract of Kaempferia galanga L. Rhizome (EEKG) harvested from the rainy (EEKG-R) and dry seasons (EEKG-D). Methods: The sun-dried rhizomes were cold macerated for 3x24 h with 70% ethanol, filtered, and the solvent was evaporated at 40-45 °C until a viscous extract was obtained. The determination of EPMC in the extract was carried out using the RP-HPLC standard addition method. Detection was set at 308 nm; injection volume 20 µl; flow rate 1.0 ml/min. The column used is C18 (length 250 mm, internal diameter 4.6 mm, particle size 5 µm). Results: The yield of EEKG-R (harvested in the rainy season) = 14.56% w/w, water content = 4.37%, and the EPMC = 0.01%. Meanwhile the yield of EEKG-D (harvested in the dry season) = 5.79% w/w, water content = 18.76%, and the EPMC = 0.001%. Conclusion: Different climates affect the percentage yield and the quality of the extract. In our work, the EEKG-R (harvested in the rainy season) revealed a better quality compared to that of EEKG-D (harvested in the dry season) This study gives important information to standardize and optimize the harvest time of KG rhizomes for drugs development, which are strongly influenced by seasonal differences.


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