Bicarbonate-Hydrogen Peroxide System for Treating Dyeing Wastewater: Degradation of Organic Pollutants and Color Removal.

The textile industry is a global economic driving force; however, it is also one of the most polluting industries, with highly toxic effluents which are complex to treat due to the recalcitrant nature of some compounds present in these effluents. This research focuses on the removal of Chemical Oxygen Demand (COD), color, Total Organic Carbon (TOC), and Ammoniacal Nitrogen (N-NH3) on tannery wastewater treatment through an advanced oxidation process (AOPs) using sodium bicarbonate (NaHCO3), hydrogen peroxide (H2O2) and temperature using a central composite non-factorial design with a surface response using Statistica 7.0 software. All experiments used a 500 mL reactor with 300 mL of tannery wastewater from a company in Cúcuta, Colombia. The physicochemical characterization was done to determine the significant absorbance peaks about the color in the wavelengths between 297 and 669 nm. Statistical analysis found that the concentration of NaHCO3 affects the removal of color and N-NH3; however, it did not affect COD and TOC. The optimal process conditions for removing the different compounds under study were: NaHCO3 1 M, H2O2 2 M, and 60 °C, with efficiencies of 92.35%, 31.93%, 68.85%, and 35.5% N-NH3, COD, color, and TOC respectively. It can be concluded that AOPs using H2O2 and NaHCO3 are recommended to remove color and N-NH3.

Mechanical Properties and Corrosion Behavior of Thermally Treated Ti-6Al-7Nb Dental Alloy.

Ti and its alloys have the most satisfactory properties for biomedical applications due to their specific strength, high corrosion resistance, and high biocompatibility. Ti-6Al-7Nb has been approved for clinical use, proving to be a viable replacement for the Ti-6Al-4V alloy that has been used for many decades in medical applications. In our study, the Ti-6Al-7Nb alloy underwent heat treatment, was cooled in various cooling media such as mineral oil and water, and was then quenched in the oven. The microstructure was investigated, and the mechanical characterization was carried out by Vickers microhardness test. Young's modulus measurements and tensile tests were performed in order to study the effect of cooling media on the material. To study the corrosion behavior, in vitro studies were performed on the Ti-6Al-7Nb samples in simulated body conditions by using artificial saliva. It was observed that the martensitic phase changed as a function of cooling media, and a less intensive cooling medium decreases strength properties' indicators as well as hardness values. The results emphasize that the use of heat treatment improves the passive layer's resistance in the presence of artificial saliva.

EIS Characterization of Ti Alloys in Relation to Alloying Additions of Ta.

The increased popularity of Ti and its alloys as important biomaterials is driven by their low modulus, greater biocompatibility, and better corrosion resistance in comparison to traditional biomaterials, such as stainless steel and Co-Cr alloys. Ti alloys are successfully used in severe stress situations, such as Ti-6Al-4V, but this alloy is related to long-term health problems and, in response, different Ti alloys composed of non-toxic and non-allergic elements such as Nb, Zr, Mo, and Ta have been developed for biomedical applications. In this context, binary alloys of titanium and tantalum have been developed and are predicted to be potential products for medical purposes. More than this, today, novel biocompatible alloys such as high entropy alloys with Ti and Ta are considered for biomedical applications and therefore it is necessary to clarify the influence of tantalum on the behavior of the alloy. In this study, various Ti-xTa alloys (with x = 5, 15, 25, and 30) were characterized using different techniques. High-resolution maps of the materials' surfaces were generated by scanning tunneling microscopy (STM), and atom distribution maps were obtained by energy dispersive X-ray spectroscopy (EDS). A thorough output of chemical composition, and hence the crystallographic structure of the alloys, was identified by X-ray diffraction (XRD). Additionally, the electrochemical behavior of these Ti-Ta alloys was investigated by EIS in simulated body fluid at different potentials. The passive layer resistance increases with the potential due to the formation of the passive layer of TiO2 and Ta2O5 and then decreases due to the dissolution processes through the passive film. Within the Ti-xTa alloys, Ti-25Ta demonstrates excellent passive layer and corrosion resistance properties, so it seems to be a promising product for metallic medical devices.

New Titanium Alloys, Promising Materials for Medical Devices.

Titanium alloys are used in medical devices due to their mechanical properties, but also for their corrosion resistance. The natural passivation of titanium-based biomaterials, on the surface of which a dense and coherent film of nanometric thickness is formed, composed mainly of TiO2, determines an apparent bioactivity of them. In this paper, the method of obtaining new Ti20MoxSi alloys (x = 0.0, 0.5, 0.75, and 1.0) is presented, their microstructure is analyzed, and their electrochemical responses in Ringer´s solution were systematically investigated by linear polarization, cyclic potential dynamic polarization, and electrochemical impedance spectroscopy (EIS). The alloys corrosion resistance is high, and no evidence of localized breakdown of the passive layer was observed. There is no regularity determined by the composition of the alloys, in terms of corrosion resistance, but it seems that the most resistant is Ti20Mo1.0Si.

Cardiomiopatía hipertrófica apical: revisión de la literatura y presentación de caso / Apical hypertrophic cardiomyopathy: literature review and presentation of case

Resumen La cardiomiopatía hipertrófica apical es una forma poco común de cardiomiopatía hipertrófica que se caracteriza por un compromiso, casi exclusivo, del ápice ventricular izquierdo, y se distingue por la morfología de as de picas en la ventriculografía. La heterogeneidad y la variabilidad en la presentación de esta patología y de su curso clínico hacen que sea un diagnóstico fácilmente omitido. Describimos el caso clínico de un paciente con cardiomiopatía hipertrófica apical que debutó con dolor precordial típico y síncope de origen cardiogénico. El propósito de este reporte es revisar las características principales de una afección poco frecuente, incluyendo su epidemiologia, diagnóstico, pronóstico y tratamiento, y así facilitar al personal médico el momento en que se enfrente a ella en la práctica clínica.

Abstract Apical hypertrophic cardiomyopathy is an uncommon form of hypertrophic cardiomyopathy characterized by a compromise of the left ventricular apex and is distinguished by the ace morphology in the ventriculography. The heterogeneity and variability in the presentation of this pathology and the clinical course, make a diagnosis easily omitted. We describe a clinical case of a patient with apical hypertrophic cardiomyopathy that debuted with precordial pain and syncope of cardiogenic origin. The purpose of this report is to review the main characteristics of a rare pathology, epidemiology, diagnosis, prognosis and treatment and thus, to provide medical personnel with the approach of this pathology in clinical practice.

Advanced Oxidation Processes and Biotechnological Alternatives for the Treatment of Tannery Wastewater.

The tannery industry is one of the economic sectors that contributes to the development of different countries. Globally, Europe and Asia are the main producers of this industry, although Latin America and Africa have been growing considerably in recent years. With this growth, the negative environmental impacts towards different ecosystem resources as a result of the discharges of recalcitrated pollutants, have led to different investigations to generate alternative solutions. Worldwide, different technologies have been studied to address this problem, biological and physicochemical processes have been widely studied, presenting drawbacks with some recalcitrant compounds. This review provides a context on the different existing technologies for the treatment of tannery wastewater, analyzing the physicochemical composition of this liquid waste, the impact it generates on human health and ecosystems and the advances in the different existing technologies, focusing on advanced oxidation processes and the use of microalgae. The coupling of advanced oxidation processes with biological processes, mainly microalgae, is seen as a viable biotechnological strategy, not only for the removal of pollutants, but also to obtain value-added products with potential use in the biorefining of the biomass.

Bloqueo de rama alternante: reporte de una complicación inusual tras implante valvular aórtico transcatéter / Alternating bundle branch block: report of an unusual complication after transcatheter aortic valve implantation

Resumen Los trastornos de la conducción representan una potencial complicación de los reemplazos valvulares percutáneos. Los bloqueos alternantes de rama, aunque son inusuales, reflejan daño extenso del sistema His Purkinje con riesgo potencial de bloqueo auriculoventricular completo, por lo cual es importante su identificación y abordaje oportuno. Se presenta el caso de una paciente femenina de 82 años con múltiples comorbilidades y estenosis aórtica severa, en seguimiento médico desde hacía un año, en quien no se había realizado reemplazo quirúrgico por negativa de la paciente y por el alto riesgo intraoperatorio. Ingresó a la institución con un cuadro clínico de disnea progresiva de un mes de evolución, se realizó ecocardiograma transtorácico documentando estenosis aórtica crítica y fue llevada a implante valvular aórtico percutáneo. Por el alto riesgo de necesidad de marcapasos peri o postprocedimiento, se realizó seguimiento con monitoreo Holter, documentando bloqueo alternante de rama, el cual no progresó a bloqueo auriculoventricular completo luego de 72 horas de seguimiento, por lo que no se implantó marcapasos permanente. MÉD.UIS.2020;33(3): 37-42

Abstract Conduction disorders represent a potential complication of percutaneous valve replacements. Alternating bundle branch block, although unusual, reflect extensive damage of the His-Purkinje system with potential risk of complete atrioventricular block, therefore, its identification and timely approach is important. We present the case of an 82 years old female patient with multiple comorbidities and a medical history of severe aortic stenosis in medical follow-up for a year, in whom surgical replacement had not been conducted due to the patient's refusal and to the high surgical risk. She was admitted to the institution referring one month of progressive shortness of breath and an echocardiogram documented critical aortic stenosis. Percutaneous aortic valve implantation was performed. Due to her high risk of needing a peri or post-procedure pacemaker, Holter monitoring was performed, documenting alternating bundle branch block, which did not progress to complete atrioventricular block after 72 hours of follow-up, in consequence, a permanent pacemaker was not implanted. MÉD.UIS.2020;33(3): 37-42

Compromiso cardiovascular secundario a tumor carcinoide metastásico / Cardiovascular compromise secondary to metastatic carcinoid tumor

Resumen Los tumores carcinoides son neoplasias pertenecientes a la familia de tumores neuroendocrinos y presentan baja incidencia en la población en general; sin embargo, hasta el 50 % pueden debutar con compromiso cardiovascular. Se presenta el caso de un paciente, sin antecedentes cardiovasculares quien presentó signos y síntomas sugestivos de falla cardiaca derecha. Se le realizó ecocardiografía transtorácica que evidenció compromiso de ambas válvulas cardíacas derechas por tumor neuroendocrino metastásico, llevando al diagnóstico de sindrome carcinoide. Con el fin de tener presente dicha entidad en la práctica diaria de la cardiología clínica se revisan datos claves de abordaje diagnóstico y terapéutico.

Abstract Carcinoid tumors are neoplasms belonging to the neuroendocrine tumor family and have a low incidence in the general population; however, up to 50% may debut with cardiovascular involvement. We present the case of a patient, without a cardiovascular history, who presented signs and symptoms suggestive of right-sided heart failure. A transthoracic echocardiography was performed, which evidenced the involvement of both right heart valves by a metastatic neuroendocrine tumor, leading to the diagnosis of carcinoid syndrome. In order to take this entity into account in the daily practice of clinical cardiology, key data of diagnostic and therapeutic approach are reviewed.

Indicadores de bioquímica sanguínea y perfil hormonal en vacas suplementadas con Trébol rojo (Trifolium pratense) / Evaluation of the consumption of red clover (trifolium pratense) on the blood profile in dairy cows / Avaliação do consumo de trevovermelho (trifolium pratense) no perfil sanguíneo em vacas leiteiras

Resumen Introducción: el trébol rojo es una leguminosa usada en la nutrición bovina por su aporte de proteína, actualmente se conoce que produce naturalmente metabolitos secundarios que son similares a los estrógenos, ocasionando alteraciones en la capacidad reproductiva de los animales. Objetivo: determinar los efectos del consumo de Trébol rojo sobre el perfil sanguíneo en vacas lecheras en la Granja Tunguavita de la UPTC. Materiales y Métodos: se seleccionaron 32 animales con características similares, se dividieron aleatoriamente en cuatro tratamientos: G1: 8 vacas con suplemento de trébol rojo según sus requerimientos, G2: 8 vacas con suplemento de trébol rojo 25% adicional, G3: 8 vacas con suplemento de trébol rojo 50% adicional y G4: ningún suplemento, durante 60 días. Antes de la suplementación, a los 30 y 60 días post suplementación se midieron variables como estradiol (E2), progesterona (P4), hormona luteinizante (LH), Triglicéridos, triyodotironina (T3), Tiroxina (T4), Insulina, hormona estimulante de la tiroides (TSH), glucosa y nitrógeno ureico en sangre (BUN). Resultados: entre los grupos suplementados con Trébol rojo no se observaron diferencias estadísticas; pero con relación al grupo control se evidencia que los valores de estradiol, LH, BUN, TSH y progesterona fueron menor que (P <0.05); por otra parte, los niveles de T3 y T4 mostraron un comportamiento similar durante todo el experimento y se observó un aumento en los valores de insulina y triglicéridos. Conclusiones: la suplementación con trébol rojo influye negativamente en la conducta reproductiva de vacas lecheras, presentándose valores inferiores en las variables evaluadas.

Abstract Introduction: red clover is a legume that has been used in bovine nutrition for its contribution of protein, is now known to naturally produce secondary metabolites that are like the estrogens of mammals, causing alterations in the reproductive capacity of animals. Objective: determine the effects of red clover consumption on blood profile in dairy cows on the farm Tunguavita of the UPTC. Materials and Methods: 32 animals with similar characteristics were selected, they were randomly divided into four treatments: T1: 8 cows with red clover supplement according to their requirements, T2: 8 cows with extra red clover supplement 25%, T3: 8 cows with extra red clover supplement 50% and T4: no supplement, for 60 days. Before supplementation, at 30- and 60-days post-supplementation, variables such as estradiol (E2), progesterone (P4), luteinizing hormone (LH), triglycerides, triiodothyronine (T3), thyroxine (T4), insulin, stimulating hormone were measured the thyroid (TSH), glucose and blood urea nitrogen (BUN). Results: among the groups supplemented with Red Clover, no statistical differences were observed; but in relation to the control group it is evident that the values of estradiol, LH, BUN, TSH and progesterone were lower than (P <0.05); On the other hand, the levels of T3 and T4 showed a similar behavior throughout the experiment and an increase in the values of insulin and triglycerides was observed. Conclusions: the supplementation with red clover has a negative effect on the reproductive behavior of dairy cows, presenting lower values in the variables evaluated.

Resumo Introdução: o trevo vermelho é uma leguminosa que tem sido utilizada na nutrição bovina por sua contribuição de proteína, atualmente conhecida por produzir naturalmente metabólitos secundários que são similares aos estrogênios dos mamíferos, causando alterações na capacidade reprodutiva dos animais. Objetivo: determinar os efeitos do consumo de trevo vermelho no perfil sanguíneo em vacas leiteiras na Fazenda Tunguavita da UPTC. Materiais e Métodos: foram selecionados 32 animais com características semelhantes, divididos aleatoriamente em quatro tratamentos: T1: 8 vacas com suplemento de trevo vermelho de acordo com suas necessidades, T2: 8 vacas com suplemento de trevo vermelho, 25% adicionais, T3: 8 vacas com Suplemento adicional de 50% de trevo vermelho e T4: sem suplemento, por 60 dias. Antes da suplementação, aos 30 e 60 dias pós-suplementação, foram medidas variáveis como estradiol (E2), progesterona (P4), hormônio luteinizante (LH), triglicérides, triiodotironina (T3), tiroxina (T4), insulina, hormônio estimulante a tiróide (TSH), glicose e nitrogênio ureico no sangue (BUN). Resultados: entre os grupos suplementados com Red Clover, não foram observadas diferenças estatísticas; mas em relação ao grupo controle, é evidente que os valores de estradiol, LH, BUN, TSH e progesterona foram menores que (P <0,05); Por outro lado, os níveis de T3 e T4 apresentaram comportamento semelhante ao longo do experimento e observou-se aumento nos valores de insulina e triglicerídeos. Conclusões: a suplementação com trevo vermelho tem efeito negativo sobre o comportamento reprodutivo de vacas leiteiras, apresentando valores inferiores nas variáveis avaliadas.

Multiparameter analysis of activated sludge inhibition by nickel, cadmium, and cobalt.

Activated sludge processes are often inhibited by nickel, cadmium, and cobalt. The inhibitory effect of these heavy metals on a synthetic wastewater treatment process was tested through pulse microrespirometry; i.e., pulse of substrate injected in a microreactor system. The inhibitory effect was tested under different conditions including the heavy metals, substrate and biomass concentrations, and exposure time. The inhibitory effect was quantified by the percentage of inhibition, half saturation constant (KS), inhibition constant (KI), and maximum oxygen uptake rate (OURmax). The results indicated that, in a range of concentration from 0 to 40 mg L-1, the three heavy metals exerted an uncompetitive and incomplete inhibitory effect, with a maximum inhibition of 67, 57, and 53% for Ni, Co, and Cd, respectively. An increase of the biomass concentration by 620% resulted in a decrease of the inhibition by 47 and 69% for Co and Cd, respectively, while no effect was observed on Ni inhibition. An increase of the substrate concentration by 87% resulted in an increase of the inhibition by 24, 70, and 47% for Ni, Co and Cd, respectively. In the case of nickel and cadmium, an increase in the exposure time to the heavy metals also increased the inhibition.

Utilización de microalgas de la división Chlorophyta en el tratamiento biológico de drenajes ácidos de minas de carbón / Use of microalgae of Chlorophyta division in the biological treatment of acid drains of coal mines

RESUMEN El impacto ambiental generado por las aguas residuales de la explotación de carbón es significativo por la carga contaminante que estas por lo general poseen, representada en grandes concentraciones de sólidos suspendidos, metales (principalmente hierro) y otros elementos traza, además del bajo pH que suelen tener. El objetivo del presente trabajo fue evaluar la eficiencia de un sistema de tratamiento biológico a partir de microalgas de la división Chlorophyta para remover la carga contaminante de las aguas residuales de una mina de la empresa Coal North Energy S.A.S. Al final del tratamiento se obtuvieron porcentajes de remoción del 66,67% para hierro total, 46,67% para cloruros y 95,1% para DQO (Demanda Química de Oxígeno).

ABSTRACT The environmental impact caused by coal mining wastewater is significant due to the pollution load, usually represented in high concentrations of suspended solids, metals (mainly iron) and other trace elements and low pH values. The aim of this study was to evaluate the efficiency of a biological treatment system using microalgae belonging to the Chlorophyta division, for the removal of contaminants from the wastewater from a mine owned by Coal North Energy S.A.S. At the end of treatment, it was possible to remove up to 66.67% of total iron, 46.67% for chloride and 95.1% for Chemical Oxigen Demand.

Modelo multinivel de tasa global de ganancia de peso en el programa madre canguro en Bogotá / Multilevel model for global weight gain rate in the kangaroo-mother program in Bogotá

Objetivos Formular un modelo multinivel para el análisis longitudinal de la tasa global de ganancia de peso en el Programa Madre Canguro. Metodología Se realiza un modelo multinivel, considerando en el primer nivel la variable tiempo y algunas variables del infante y de la madre; para el segundo nivel se consideran las mediciones asociadas a la tasa global de ganancia de peso. Resultados Al 5 % de significancia el intercepto y el parámetro asociado a la variable días transcurridos desde el nacimiento al cuadrado tienen efecto significativo sobre la tasa global de ganancia de peso. La pendiente para la variable días transcurridos desde el nacimiento resulta ser significativa al nivel del 6 %. Además, bajo este modelo se encuentra que el género y el retraso de crecimiento intrauterino del infante no tienen efecto significativo, así como la talla y el perímetro en los diferentes controles del infante. El peso en los diferentes controles del infante resulta ser significativo al 5 %, pero hay diferencias entre las dos clasificaciones gestacionales del infante (1: 26 a 40 semanas; 2: mayor de 40 semanas) y entre las clasificaciones del peso del infante de las categorías dos con uno, y tres con uno (1: 2500 gm. o más; 2: entre 1500 y 2499 gm.; 3: menor de 1500 gm.). Conclusión Por cada cita adicional menor es la tasa de ganancia de peso en promedio que va a tener el infante; sin embargo, el infante sigue ganando peso pero no en la misma razón de ganancia de las primeras citas.(AU)

Objectives To formulate a multilevel model for the longitudinal study of global weight gain rate in the Kangaroo-Mother Care Program. Methodology A multilevel model is used, taking time and some infant and mother variables in the first level. Measures associated with the global weight gain rate are considered for the second level. Results At 5 % significance, the intercept and the parameter associated to the time (days after birth) squared variable have a significant effect on the global rate of weight gain. The slope for the time variable is significant at the 6 % level. Also, under this model, we find that the gender delay in intrauterine growth of the infant, height and perimeter do not have a significant effect on the infant's global rate of weight gain. The weight in the various controls performed is significant at the 5 % level. There are differences between the two infant's gestational classifications (1: 26 to 40 weeks; 2: greater than 40 weeks), and between the infant's weight classifications of the categories two with one, and three with one (1: 2500 gm or more; 2: between 1500 and 2499 gm; 3: less than 1500 gm). Conclusion For each additional appointment, the average weight gain rate of the infant decreases. However, the infant keeps gaining weight, but not at the same rate as in the initial appointments.(AU)

[Multilevel model for global weight gain rate in the kangaroo-mother program in Bogotá]. / Modelo multinivel de tasa global de ganancia de peso en el programa madre canguro en Bogotá.

Objectives To formulate a multilevel model for the longitudinal study of global weight gain rate in the Kangaroo-Mother Care Program. Methodology A multilevel model is used, taking time and some infant and mother variables in the first level. Measures associated with the global weight gain rate are considered for the second level. Results At 5 % significance, the intercept and the parameter associated to the time (days after birth) squared variable have a significant effect on the global rate of weight gain. The slope for the time variable is significant at the 6 % level. Also, under this model, we find that the gender delay in intrauterine growth of the infant, height and perimeter do not have a significant effect on the infant's global rate of weight gain. The weight in the various controls performed is significant at the 5 % level. There are differences between the two infant's gestational classifications (1: 26 to 40 weeks; 2: greater than 40 weeks), and between the infant's weight classifications of the categories two with one, and three with one (1: 2500 gm or more; 2: between 1500 and 2499 gm; 3: less than 1500 gm). Conclusion For each additional appointment, the average weight gain rate of the infant decreases. However, the infant keeps gaining weight, but not at the same rate as in the initial appointments.