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Reducing the economic and environmental impact of industrial process may be achieved by the smartisation of different components. In this work, tube smartisation is presented via direct fabrication of a copper (Cu)-based resistive temperature detector (RTD) on their outer surfaces. The testing was carried out between room temperature and 250 °C. For this purpose, copper depositions were studied using mid-frequency (MF) and high-power impulse magnetron sputtering (HiPIMS). Stainless steel tubes with an outside inert ceramic coating were used after giving them a shot blasting treatment. The Cu deposition was performed at around 425 °C to improve adhesion as well as the electrical properties of the sensor. To generate the pattern of the Cu RTD, a photolithography process was carried out. The RTD was then protected from external degradation by a silicon oxide film deposited over it by means of two different techniques: sol-gel dipping technique and reactive magnetron sputtering. For the electrical characterisation of the sensor, an ad hoc test bench was used, based on the internal heating and the external temperature measurement with a thermographic camera. The results confirm the linearity (R2 > 0.999) and repeatability in the electrical properties of the copper RTD (confidence interval < 0.0005).
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Cobre , Acero Inoxidable , Propiedades de Superficie , CerámicaRESUMEN
Tribological coatings made of MoS2 and WSe2 phases and their corresponding combinations with tungsten carbide (WC) were prepared by non-reactive magnetron sputtering of individual targets of similar composition. A comparative tribological analysis of these multiphase coatings was done in both ambient air (30-40% relative humidity, RH) and dry nitrogen (RH<7%) environments using the same tribometer and testing conditions. A nanostructural study using advanced transmission electron microscopy of the initial coatings and examination of the counterfaces after the friction test using different analytical tools helped to elucidate what governs the tribological behavior for each type of environment. This allowed conclusions to be made about the influence of the coating microstructure and composition on the tribological response. The best performance obtained with a WSex film (specific wear rate of 2 × 10-8 mm3 N-1m-1 and a friction coefficient of 0.03-0.05) was compared with that of the well-established MoS2 lubricant material.
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A combination of transmission electron microscopy techniques and spatially resolved microanalysis is used to investigate the nanostructure, constituting phases, and chemical elemental distribution in CrAlYN multilayered coatings. The location of the metallic elements and their chemical state are needed to understand their functional properties. Samples were prepared with variable Al (4-12 at%) and Y (2-5 at%) contents by direct current reactive magnetron sputtering on silicon substrates using metallic targets and Ar/N2 mixtures under different deposition parameters (power applied to the target and rotation speed of the sample holder). The changes produced in the nanostructure and chemical distribution were investigated. Nanoscale resolution electron microscopy analysis has shown that these coatings present a singular nanostructure formed by multilayers containing at a certain periodicity nanovoids filled with molecular nitrogen. Spatially resolved energy dispersive spectroscopy and electron energy loss elemental mappings and profiles showed that the chromium, aluminum, and yttrium atoms are distributed in a sequential way following the position of the targets inside the deposition chamber. Analysis of the different atomic distribution and phases formed at the nanoscale is discussed depending on the deposition parameters.
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Preventing microbiological surface contamination in public spaces is nowadays of high priority. The proliferation of a microbial infection may arise through air, water, or direct contact with infected surfaces. Chemical sanitization is one of the most effective approaches to avoid the proliferation of microorganisms. However, extended contact with chemicals for cleaning purposes such as chlorine, hydrogen peroxide or ethanol may lead to long-term diseases as well as drowsiness or respiratory issues, not to mention environmental issues associated to their use. As a potentially safer alternative, in the present work, the efficacy and endurance of the antimicrobial activity of different sol-gel coatings were studied, where one or two biocides were added to the coating matrix resulting on active groups exposed on the surface. Specifically, the coating formulations were synthesized by the sol-gel method. Using the alkoxide route with acid catalysis a hybrid silica-titania-methacrylate matrix was obtained where aromatic liquid eugenol was added with a double function: as a complexing agent for the chelation of the reaction precursor titanium isopropoxide, and as a biocide. In addition, 2-Phenylphenol, ECHA approved biocide, has also been incorporated to the coating matrix. The antibacterial effect of these coatings was confirmed on Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli). Additionally, the coatings were non cyto-toxic and displayed virucidal activity. The coating chemical composition was characterized by 29Si NMR, and ATR-FTIR. Furthermore, the thickness and the mechanical properties were characterized by profilometry and nanoindentation, respectively. Finally, the durability of the coatings was studied with tribology tests. Overall, our data support the efficacy of the tested sol-gel coatings and suggest that added features may be required to improve endurance of the antimicrobial effects on operational conditions.
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Introducción: La presencia de hipertensión arterial en población joven aumenta el riesgo de eventos cardiovasculares en la mediana edad y como consecuencia una morbimortalidad prematura. El propósito de este estudio es evaluar la progresión de los componentes de la presión arterial y la correlación con las medidas antropométricas y laboratoriales en estudiantes de la Universidad Nacional de Asunción- Paraguay. Materiales y métodos: Se realizó un estudio descriptivo correlacional, longitudinal, prospectivo, desde el año 2013 hasta el año 2017 evaluando al inicio 284 universitarios y 240 al final de las carreras. Se midieron variables sociodemográficas, antropométricas, presión arterial, determinaciones bioquímicas. La progresión de los componentes de la presión arterial, de las variables antropométricas y clínicas se calcularon mediante la prueba T de muestras relacionadas. La correlación de la presión arterial sistólica y presión arterial diastólica con las variables antropométricas y laboratoriales con la correlación de Pearson. Resultados: La progresión de los componentes de la presión arterial presentó una diferencia estadísticamente significativa en la presión arterial sistólica, presión arterial diastólica y presión de pulso. En relación con las características antropométricas y clínicas de los estudiantes se encontró una diferencia estadísticamente significativa entre la medición inicial y final en el peso, perímetro abdominal, glicemia, insulina, colesterol total, colesterol de alta densidad, colesterol de baja densidad, triglicéridos y proteína C reactiva. La correlación más importante encontrada entre las medidas antropométricas con la presión arterial sistólica y presión arterial diastólica fue la circunferencia abdominal. Conclusión: Se encontró aumento de la tendencia de la presión arterial y de otros factores de riesgo cardiovascular en universitarios.
Introduction: The presence of arterial hypertension in young population increases the risk of cardiovascular events in middle age and as a consequence premature morbimortality. The purpose of this study was to evaluate the progression of blood pressure components and the correlation with anthropometric and laboratory measurements in students of the National University of Asuncion, Paraguay. Materials and methods: A descriptive correlational, longitudinal, prospective, descriptive study was conducted from 2013 to 2017 evaluating at the beginning 284 undergraduates and 240 at the end of the careers. Sociodemographic variables, anthropometric variables, blood pressure, biochemical determinations were measured. The progression of blood pressure components, anthropometric and clinical variables were calculated using the related samples t-test. The correlation of systolic blood pressure and diastolic blood pressure with anthropometric and laboratory variables was correlated with Pearson's correlation. Results: The progression of blood pressure components presented a statistically significant difference in systolic blood pressure, diastolic blood pressure and pulse pressure. In relation to the anthropometric and clinical characteristics of the students, a statistically significant difference was found between the initial and final measurements in weight, abdominal perimeter, glycemia, insulin, total cholesterol, high-density cholesterol, low-density cholesterol, triglycerides, and C-reactive protein. The most important correlation found between anthropometric measurements with systolic blood pressure and diastolic blood pressure was abdominal circumference. Conclusion: An increase in the trend of blood pressure and other cardiovascular risk factors was found in university students.
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Presión Arterial , Presión , HipertensiónRESUMEN
RESUMEN Los factores de riesgo cardiovascular empiezan a edad temprana de la vida y causan morbimortalidad prematura. Se evaluó la progresión de hipertensión arterial y de otros factores de riesgo cardiovascular en estudiantes de la Universidad Nacional de Asunción- Paraguay. Estudio descriptivo en el que se compararon dos mediciones transversales (año 2013 y 2017). Se estudió a 284 universitarios al inicio y a 240 al final de las carreras. Se midieron variables sociodemográficas, antropométricas, presión arterial, determinaciones bioquímicas, consumo de alcohol y tabaco. La presión arterial se clasificó según el Séptimo informe del Comité Nacional para la Prevención, Detección, Evaluación y Tratamiento de la Hipertensión arterial. Se aplicó la prueba t-Student para variables continuas y Chi cuadrado para variables categóricas y regresión logística para asociación entre hipertensión y factores de riesgo cardiovascular. Se encontró hipertensión en el grupo año 2013 en 6,7% (IC del 95%:3,4-10%) de los estudiantes y en el grupo año 2017 en 21,2% (IC del 95%:17,8-24,6%) de los estudiantes (p= <0,001). En hombres se encontró aumento de la tendencia de c-HDL disminuido, triglicéridos aumentados, consumo de alcohol y en el índice de resistencia a la insulina (p<0,05), y en mujeres aumento del consumo de alcohol, del hábito sedentario y del índice de resistencia a la insulina (p < 0,05). Había una asociación de la hipertensión con la circunferencia abdominal aumentada (OR: 15,7; IC del 95%: 4,6-53,5; p=<0,001). Se encontró aumento de la tendencia de la presión arterial y de otros factores de riesgo cardiovascular en universitarios.
ABSTRACT Cardiovascular risk factors begin at an early age of life and cause premature morbidity and mortality. The progression of arterial hypertension and other cardiovascular risk factors in students of the National University of Asunción-Paraguay was evaluated. Descriptive study in which two cross-sectional measurements (year 2013 and 2017) were compared. Two hundred eighty-four university students were studied at the beginning and 240 at the end of their careers. Sociodemographic, anthropometric, blood pressure, biochemical determinations, alcohol and tobacco consumption were measured. Blood pressure was classified according to the Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation and Treatment of High Blood Pressure. The t-Student test was applied for continuous variables and Chi square for categorical variables and logistic regression for association between hypertension and cardiovascular risk factors. Hypertension was found in the 2013 group in 6.7% (95% CI: 3.4-10%) of the students and in the 2017 group in 21.2% (95% CI: 17.8-24, 6%) of the students (p = <0.001). In men, there was an increase in the tendency of decreased c-HDL, increased triglycerides, alcohol consumption and insulin resistance index (p <0.05), and in women an increase in alcohol consumption, sedentary habits and insulin resistance index (p <0.05). There was an association of hypertension with increased abdominal circumference (OR: 15.7; 95% CI: 4.6-53.5; p = <0.001). An increase was found in the tendency of blood pressure and other cardiovascular risk factors in university students.
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Introducción: La Diabetes Mellitus tipo 2 es una enfermedad metabólica muy frecuente, siendo una de las principales causas de mortalidad en nuestro país. El enfoque integral, individual, familiar y comunitario de la Atención Primaria de Salud a través de las Unidades de Salud de la Familia permite identificar síntomas de depresión que pueden aparecer durante el curso de la enfermedad. Objetivo: Determinar los niveles de depresión según la cronicidad de la Diabetes Mellitus tipo 2 y sus comorbilidades en pacientes de las Unidades de Salud del distrito de Encarnación en el año 2018. Metodología: Estudio con diseño observacional, analítico de corte transversal sobre 228 pacientes con Diabetes Mellitus tipo 2 entrevistados durante el año 2018. Se aplicó un formulario validado con el test de Kuder- Richardson y la Escala de Hamilton para la depresión. Los datos fueron procesados en EpiInfo v. 7. Resultados: Se detectó depresión en el 66,7 % (152) de las personas incluidas en el estudio, siendo más frecuente la depresión ligera presente en el 32, 9 % (75) de los casos, seguido de depresión moderada y grave. Se encontró asociación estadísticamente significativa entre depresión y años de evolución de Diabetes Mellitus tipo 2 (p = 0.029), hipertensión (p = 0.0024); neuropatía (p = 0.0003). Conclusión: El nivel de depresión más frecuente fue la ligera y la presencia de síntomas de depresión en pacientes con Diabetes Mellitus tipo 2 fue alta, asociada significativamente con años de evolución de la diabetes, hipertensión y neuropatía. Palabras clave: Diabetes mellitus, Depresión, Atención Primaria de Salud.
Introduction: Type 2 Diabetes Mellitus is a very frequent metabolic disease, being one of the main causes of mortality in our country. The integral, individual, family and community approach of Primary Health Care through the Family Health Units allows to identify symptoms of depression that may appear during the course of the disease. Objective: To determine the levels of depression according to the chronicity of Type 2 Diabetes Mellitus and its comorbidities in patients of the Health Units of the district of Encarnación in the year 2018. Methodology: Study with observational, analytical cross-sectional design on 228 patients with Type 2 Diabetes Mellitus interviewed during 2018. A validated form was applied with the Kuder-Richardson test and the Hamilton Scale for depression. The data was processed in EpiInfo v. 7. Results: Depression was detected in 66.7% (152) of the people included in the study, with mild depression being more frequent in 32.9% (75) of the cases, followed by moderate and severe depression. A statistically significant association was found between depression and years of evolution of Type 2 Diabetes Mellitus (p = 0.029), hypertension (p = 0.0024); neuropathy (p = 0.0003). Conclusion: The most frequent level of depression was mild and the presence of depression symptoms in patients with Type 2 Diabetes Mellitus was high, significantly associated with years of evolution of diabetes, hypertension and neuropathy. Keywords: Diabetes mellitus, Depression, Primary Health Care.
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Humanos , Masculino , Femenino , Atención Primaria de Salud , Depresión , Diabetes Mellitus/psicología , Enfermedad Crónica/psicologíaRESUMEN
Antecedente: actualmente existen 2 tipos de inhibidores de ciclooxigenasa, COX 1 y COX 2, que actúan sobre el ácido araquidónico y el primero es el principal implicado en la intolerancia a los AINE. Los COX 2 selectivos y específicos son la alternativa terapéutica en pacientes con éste tipo de reacción. Objetivos: conocer el porcentaje de intolerancia al rofecoxib (inhibidor COX 2 específico) en paciente con intolerancia a AINE. Métodos: se seleccionaron 30 pacientes con intolerancia a AINE, a quienes se les realizó una prueba de provocación controlada oral (PPCO) con 25 mg de rofecoxib, un VEF1 basal y controles a los 15, 30, 45, 60, 75, 120 minutos y a las 24, 48 y 72 horas, y 30 pacientes sanos como grupo control. Resultados: una paciente presentó urticaria en cuello, parte superior del tronco y prurito generalizado a los 30 minutos con 12,5 mg de rofecoxib y 29 pacientes toleraron el fármaco. Conclusiones: a pesar de la buena tolerancia del rofecoxib, una paciente, también intolerante a los AINE, presentó reacción adversa al fármaco