Validation of a Computational Fluid Dynamics Model for a Novel Residence Time Distribution Analysis in Mixing at Cross-Junctions

[EN] In Water Distribution Networks, the chlorine control is feasible with the use of water quality simulation codes. EPANET is a broad domain software and several commercial computer software packages base their models on its methodology. However, EPANET assumes that the solute mixing at cross-junctions is ¿complete and instantaneous¿. Several authors have questioned this model. In this paper, experimental tests are developed while using Copper Sulphate as tracer at different operating conditions, like those of real water distribution networks, in order to obtain the Residence Time Distribution and its behavior in the mixing as a novel analysis for the cross-junctions. Validation tests are developed in Computational Fluid Dynamics, following the k-# turbulence model. It is verified that the mixing phenomenon is dominated by convection, analyzing variation of Turbulent Schmidt Number vs. experimental tests. Having more accurate mixing models will improve the water quality simulations to have an appropriate control for chlorine and possible contaminants in water distribution networks.To CONACYT for the Master and Ph.D. scholarships (417824 and 703220) to D.H.-C. and the Ph.D. scholarship (294038) to M.R.; To Universidad de Guanajuato for the financial support of the project No. 100/2018 of J.L.N.; To Engineering Division, Campus Guanajuato and Geomatics and Hydraulics Engineering Department for the financial support of this project; and finally, to SEP-PRODEP and UG for the financial support to publish this paper.Hernandez Cervantes, D.; Delgado Galván, XV.; Nava, JL.; López Jiménez, PA.; Rosales, M.; Mora Rodríguez, JDJ. (2018). Validation of a Computational Fluid Dynamics Model for a Novel Residence Time Distribution Analysis in Mixing at Cross-Junctions. Water. 10(6):1-18. https://doi.org/10.3390/w10060733S118106Mercier Shanks, C., Sérodes, J.-B., & Rodriguez, M. J. (2013). 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Intervención de urbanismo táctico para la implementación de cruces seguros

A lo largo de este reporte se informa sobre las distintas labores, investigaciones y visitas de campo que se llevan a cabo en el Proyecto de Aplicación Profesional de Movilidad en el periodo de primavera 2021. Durante el cual se abordó la problemática de movilidad urbana y falta de infraestructura que cotidianamente experimentan los usuarios que atraviesan el cruce de Av. Ramón Corona, Colegiales, Libertad y C. Degollado, denominado “Área de intervención”, ubicado en la colonia Mexicaltzingo, Guadalajara, Jal. La confluencia de diferentes dinámicas de las unidades transporte público colectivo en la zona, así como la falta de regulación y organización de las mismas generan un evidente desorden en materia de movilidad en el cruce de las calles anteriormente mencionadas, dicha problemática sumada a la ausencia infraestructura y señalética urbana adecuada que dote de claridad al espacio, pone en riesgo la vida de miles de usuarios que hacen uso del mismo diariamente, especialmente al peatón ya que la complejidad de la intersección de varias vialidades sumado a las falta de claridad en el espacio y los movimientos de transporte motorizado generan cruces inseguros entre vialidades que exponen al peatón. El objetivo principal de este trabajo es generar una intervención de urbanismo táctico así como una propuesta formal de implementación de cruces seguros en la intersección anteriormente mencionada, esto con la finalidad de organizar los movimientos peatonales en vialidades del área de intervención. La propuesta desarrollada podrá servir como un incentivo para que las autoridades correspondientes intervengan y ejecuten un proyecto de urbanismo permanente en base a la intervención de urbanismo táctico y la propuesta formal generada como resultado de este proyecto. Utilizamos una metodología de investigación mixta, por un lado utilizamos un abordaje cuantitativo para observar elementos medibles en el espacio, mientras que el abordaje cualitativo fue útil para obtener información acerca de la calidad del mismo.ITESO, A.C

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Ultrasonografía vascular en pacientes con hepatopatías crónicas de causa desconocida

Se realizó un estudio prospectivo y transversal de 69 pacientes con hepatopatías crónicas de causa desconocida, atendidos en el Departamento de Imagenología del Hospital Provincial Docente Clinicoquirúrgico "Saturnino Lora Torres" de Santiago de Cuba, desde enero del 2009 hasta agosto del 2010, a fin de determinar las alteraciones ultrasonográficas vasculares en los afectados. Predominaron el grupo etario de 52-59 años (39,1 %), el sexo masculino (69,6 %), la localización prehepática (44,9 %), las trombosis de la vena porta (47%), la dilatación de venas suprahepáticas (89,7%) y las causas prehepáticas (44,9%). Las ecografías Doppler dúplex y Doppler color permitieron establecer pautas diagnósticas en estos pacientes, sin afectar el completamiento de su evaluación con otros estudios hemodinámico

Physiological response to hypoxia in piglets of different birth weight

In the present study, we aimed to extend the characterization of the proposed naturalistic experimental model of piglets born with hypoxia by assessing the relationship between birth weight, intra partum asphyxia and gross indicators of neurophysiological alterations in newborn piglets. Three groups of 50 piglets each were classified according to their birth weight into normal (1000-1350 g), low (below 1000 g), and high (over 1350 g). In comparison to piglets within normal weight, those born with high birth weights showed acid-base imbalance as reflected by lower pH levels (7.03±0.01), hypercapnia (88.50±13.20 mmHg), and lactic acidosis (lactate levels: 89.40±26.30). These piglets had lower viability scores (5.40±0.60) and longer periods of time to contact the udder (52.30±8.30) than piglets with normal birth weight. In conclusion, data show that piglets with birth weight over 1350 g are at a higher risk of gross neurophysiological deficits, probably secondary to neonatal hypoxia

Valuación de inmuebles con prácticas

El INSTITUTO POLITÉCNICO NACIONAL es una institución educativa laica, gratuita del Estado, rectora de la educación tecnológica pública en México, líder en la generación, aplicación, difusión y transferencia del conocimiento científico y tecnológico, creada para contribuir al desarrollo económico, social y político de la nación. Para lograrlo, el Instituto y su comunidad forman integralmente profesionales en los niveles medio superior, superior y posgrado, realiza investigación y extiende a la sociedad sus resultados, con calidad, responsabilidad, ética, tolerancia y compromiso social. La Escuela Superior de Ingeniería y Arquitectura Unidad Zacatenco, es una de las once escuelas superiores en el área de Ingeniería y Ciencias Físico-Matemáticas, del INSTITUTO POLITÉCNICO NACIONAL

II Congreso de Educación: UNA nueva mirada en la mediación pedagógica

Memoria incluye las ponencias presentadas en el II Congreso de Educación, celebrado en Sede Chorotega, 2019El acto de educar requiere de escenarios educativos propicios, para la construcción del conocimiento y el desarrollo de valores humanos, donde la emoción y los pensamientos de cada ser humano son fundamentales. Si las emociones y sentimientos provocan cambios estructurales, químicos, energéticos y neuronales esta debe visibilizarse en el aula. La química del aprendizaje debe estar presente en todo momento; de modo que, se deben estimular todas las áreas que conforman el cerebro. Por ello, el educador debe promover ambientes que fomenten distintas vivencias, con el fin de lograr la interacción entre la mente y el cuerpo del aprendiente, así como, la relación de este con el resto de sus iguales. Es el momento, de atender la problemática generalizada de la desmotivación del alumnado, es la hora de reencantar la educación, de nutrir el pensamiento, los sentimientos y la correcta aplicación de los aprendizajes, es la hora de hacer vibrar el alma y los corazones de los aprendientes. En este sentido, las aulas son el lugar perfecto, para la interacción, es ahí en donde el educador tiene la plena conciencia de quién y cómo es cada aprendiente, es en ese recinto, en donde es más fácil comprender a ese ser humano en su totalidad. Esto, le permite ayudarlo a desarrollar mejor sus potencialidades, sus talentos, sus competencias y sus habilidades, para que, como un Ser pleno, durante el proceso educativo, desarrolle actos de amor; además, de valores tales como la solidaridad y la colaboración, acciones que le permiten alcanzar la finalidad de la existencia humana, que es encontrar prolongados estados de bienestar y felicidad.Universidad NacionalUniversidad Naciona