Desarrollo de un sistema de imágenes Raman para detección de fitopatógenos.

Los fitopatógenos son microorganismos capaces de infectar plantas según sus características y entornos. Normalmente los fitopatógenos existen en forma de hongos, bacterias, protozoos, etc. que invaden diferentes partes de una planta como el fruto, hojas, tallos, entre otros, lo cual obligaría a un agricultor a una constante inspección por sintomatología para tomar medidas correctivas y oportunas en un cultivo. En este trabajo se abordó el tema de detección no convencional de dos especies de fitopatógenos fúngicos: \textit{Mycosphaerella fijiensis} y \textit{Colletotrichum gloeosporioides}, cuyo foco de infección son cultivos de alto valor comercial para la agro industria colombiana, principalmente banano y aguacate. Para tal fin, y teniendo en cuenta que un hongo altera la configuración energética de la estructura molecular de una planta, entonces se optó por desarrollar la técnica Raman, e incluso se diseñó y se configuró un equipo de muestreo para tal fin. El equipo construido incluye algunos dispositivos ópticos convencionales como lentes, prismas, espejos, y filtros pero también se complementó con otros sistemas de última tecnología como una cámara CCD PTGrey, y un espectrómetro B\ and W-Tech, obteniendo en definitiva un sistema de muestreo versátil y capaz de trabajar en cualquier ambiente. La detección y el registro de las señales Raman que aquí se obtuvieron corresponden a aquéllas provenientes de moléculas características de la pared celular de estos organismos, tales como quitina y $\beta$ 1,3-glucano, y que se caracterizan por una eficiencia que perfectamente garantiza su utilidad en procesos de control de calidad tanto en las etapas de cosecha como en poscosecha, indicando al usuario la presencia de estos organismos en una fase temprana, a través de imágenes que hacen posible interpretar la información espectral sin necesidad de personal experto, logrando de esta forma brindar un margen de maniobra suficiente para adoptar medidas correctivas al agricultor, haciendo posible evitar la fumigación indiscriminada de los cultivos. Para lograr esto, el equipo fue sometido a un proceso de calibración con diferentes sustancias y en fases diferentes con el propósito de garantizar las condiciones óptimas de operatividad del equipo. Todo esto fue acompañado por otros desarrollos paralelos como configuraciones ópticas auxiliares, interfases electrónicas y de control, diseños mecánicos, sistemas termodinámicos de enfriamiento en el lugar de la muestra, y desarrollo de software. El resultado es un dispositivo capaz de tomar imágenes espectrales, que posteriormente se puede utilizar para entrenar una red neuronal, que en relación a la detección de fitipatógenos en plantas permite garantizar una estimación de más del 90\% de éxito en este proceso.Abstract: Phytopathogens are microorganisms capable of infecting plants according to their characteristics and environments. Normally phytopathogens exist in the form of fungi, bacteria, protozoa, etc. that invade different parts of a plant such as fruit, leaves, stems, among others, which would force a farmer to a constant inspection for symptoms to take corrective and timely measures in a crop. In this work the topic of unconventional detection of two species of fungal phytopathogens was addressed: \textit{Mycosphaerella fijiensis} and \textit{Colletotrichum gloeosporioides}, whose focus of infection are crops of high commercial value for the Colombian agro industry, mainly bananas and avocado. For this purpose, and taking into account that a fungus alters the energy configuration of the molecular structure of a plant, then it was decided to develop the Raman technique; a sampling equipment was designed and configured for this purpose. The built equipment includes some conventional optical devices such as lenses, prisms, mirrors, and filters but it was also complemented with other state-of-the-art systems such as a PTGrey CCD camera, and a B \ and W-Tech spectrometer, ultimately obtaining a versatile sampling system and able to work in any environment. The detection and recording of the Raman signals obtained here correspond to those coming from molecules characteristic of the cell wall of these organisms, such as chitin and $\beta$-1,3-glucan, and which are characterized by an efficiency that perfectly guarantees its usefulness in quality control processes in both the harvest and post-harvest stages, indicating to the user the presence of these organisms at an early stage through images that make it possible to interpret the spectral information without the need for expert personnel, thus achieving a sufficient margin of maneuver to adopt corrective measures, making it possible to avoid the indiscriminate spraying of crops. To achieve this, the equipment was subjected to a calibration process with different substances and in different phases with the purpose of guaranteeing the optimum conditions of operation of the equipment. All this was accompanied by other parallel developments such as auxiliary optical configurations, electronics, control interfaces, mechanical designs, thermodynamic cooling systems at the sample site, and software development. The result is a device capable of taking spectral images, which can later be used to train a neural network, which in relation to the detection of phytopathogens in plants allows to guarantee a 90\% of success in this process.Doctorad

Modelo de ánodo y validación experimental para una celda de combustible microbiana

Resumen: El presente trabajo, aborda el modelamiento matemático y termodinámico de un ánodo para una celda de combustible microbiana empleando la cepa \textit{E.coli} así como su validación experimental mediante el desarrollo de una metodología, esta con el fin de determinar algunos parámetros necesarios para alimentar el modelo (p.ej Electrodo de disco rotatorio) y establecer el grado de validez de la representación matemática del ánodo.\\ Este modelo incluye el abordaje desde dos perspectivas, la primera enmarcada en los fenómenos de transporte, la cual incluye el modelamiento mediante la herramienta computacional FreeFem++, la segunda, consiste en la presentación de este modelo pero empleando la termodinámica de procesos irreversibles, con el fin de mostrar la importancia de los fenómenos cruzados en la descripción matemática de las celdas de combustible microbianas, al final se concluye cual de las dos aproximaciones fue mas importante a la hora de determinar la densidad de corriente en estos dispositivos.Maestrí

Hispano-Americans in Europe: what do we know about their health status and determinants? A scoping review.

BACKGROUND: Policy makers and health practitioners are in need of guidance to respond to the growing geographic mobility of Hispano-American migrants in Europe. Drawing from contributions from epidemiology, social sciences, demography, psychology, psychiatry and economy, this scoping review provides an up-to-date and comprehensive synthesis of studies addressing the health status and determinants of this population. We describe major research gaps and suggest specific avenues of further inquiry. METHODS: We identified systematically papers that addressed the concepts "health" and "Hispano Americans" indexed in five data bases from Jan 1990 to May 2014 with no language restrictions. We screened the 4,464 citations retrieved against exclusion criteria and classified 193 selected references in 12 thematic folders with the aid of the reference management software ENDNOTE X6. After reviewing the full text of all papers we extracted relevant data systematically into a table template to facilitate the synthesising process. RESULTS: Most studies focused on a particular disease, leaving unexplored the interlinkages between different health conditions and how these relate to legislative, health services, environmental, occupational, and other health determinants. We elucidated some consistent results but there were many heterogeneous findings and several popular beliefs were not fully supported by empirical evidence. Few studies adopted a trans-national perspective and many consisted of cross-sectional descriptions that considered "Hispano-Americans" as a homogeneous category, limiting our analysis. Our results are also constrained by the availability and varying quality of studies reviewed./nCONCLUSIONS:/nBurgeoning research has produced some consistent findings but there are huge gaps in knowledge. To prevent unhelpful generalisations we need a more holistic and nuanced understanding of how mobility, ethnicity, income, gender, legislative status, employment status, working conditions, neighbourhood characteristics and social status intersect with demographic variables and policy contexts to influence the health of the diverse Hispano-American populations present in Europe

Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study an international prospective cohort study

We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care. We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)

Safety of hospital discharge before return of bowel function after elective colorectal surgery

© 2020 BJS Society Ltd Published by John Wiley & Sons LtdBackground: Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function. Methods: A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien–Dindo classification system. Results: A total of 3288 patients were included in the analysis, of whom 301 (9·2 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4–7) and 7 (6–8) days respectively (P < 0·001). There were no significant differences in rates of readmission between these groups (6·6 versus 8·0 per cent; P = 0·499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0·90, 95 per cent c.i. 0·55 to 1·46; P = 0·659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34·7 versus 39·5 per cent; major 3·3 versus 3·4 per cent; P = 0·110). Conclusion: Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients