Object-Based Greenhouse Mapping Using Very High Resolution Satellite Data and Landsat 8 Time Series

Greenhouse mapping through remote sensing has received extensive attention over the last decades. In this article, the innovative goal relies on mapping greenhouses through the combined use of very high resolution satellite data (WorldView-2) and Landsat 8 Operational Land Imager (OLI) time series within a context of an object-based image analysis (OBIA) and decision tree classification. Thus, WorldView-2 was mainly used to segment the study area focusing on individual greenhouses. Basic spectral information, spectral and vegetation indices, textural features, seasonal statistics and a spectral metric (Moment Distance Index, MDI) derived from Landsat 8 time series and/or WorldView-2 imagery were computed on previously segmented image objects. In order to test its temporal stability, the same approach was applied for two different years, 2014 and 2015. In both years, MDI was pointed out as the most important feature to detect greenhouses. Moreover, the threshold value of this spectral metric turned to be extremely stable for both Landsat 8 and WorldView-2 imagery. A simple decision tree always using the same threshold values for features from Landsat 8 time series and WorldView-2 was finally proposed. Overall accuracies of 93.0% and 93.3% and kappa coefficients of 0.856 and 0.861 were attained for 2014 and 2015 datasets, respectively

MACHINE LEARNING AND BIG DATA TECHNIQUES FOR SATELLITE-BASED RICE PHENOLOGY MONITORING

New sources of information are required to support rice production decisions. To cope with this challenge, studies have found practical applications on mapping rice using remote sensing techniques. This study attempts to implement a methodology aimed at monitoring rice phenology using optical satellite data. The relationship between rice phenology and reflectance metrics was explored at two levels: growth stages and biophysical modifications caused by diseases. Two optical moderate-resolution missions were combined to detect growth phases. Three machine-learning approaches (random forest, support vector machine, and gradient boosting trees) were trained with multitemporal NDVI data. Analytics from validation showed that the algorithms were able to estimate rice phases with performances above 0.94 in f-1 score. Tested models yielded an overall accuracy of 71.8%, 71.2%, 60.9% and 94.7% for vegetative, reproductive, ripening and harvested categories. A second exploration was carried out by combining Sentinel-2 data and ground-based information about rice disease incidence. K-means clustering was used to map rice biophysical changes across reproductive and ripening phases. The findings ascertained the remote sensing capabilities to create new information about rice for Colombia’s conditions

Machine learning and big data techniques for satellite-based rice phenology

New sources of information are required to support rice production decisions. To cope with this challenge, studies have found practical applications on mapping rice using remote sensing techniques. This study attempts to implement a methodology aimed at monitoring rice phenology using optical satellite data. The relationship between rice phenology and reflectance metrics was explored at two levels: growth stages and biophysical modifications caused by diseases. Two optical moderate-resolution missions were combined to detect growth phases. Three machine-learning approaches (random forest, support vector machine, and gradient boosting trees) were trained with multitemporal NDVI data. Analytics from validation showed that the algorithms were able to estimate rice phases with performances above 0.94 in f-1 score. Tested models yielded an overall accuracy of 71.8%, 71.2%, 60.9% and 94.7% for vegetative, reproductive, ripening and harvested categories. A second exploration was carried out by combining Sentinel-2 data and ground-based information about rice disease incidence. K-means clustering was used to map rice biophysical changes across reproductive and ripening phases. The findings ascertained the remote sensing capabilities to create new information about rice for Colombia’s conditions

Asociación entre el uso de secuencias sonoras personalizadas y niveles de estrés y dolor en pacientes intervenidos quirúrgicamente, en el Hospital de los Valles en Quito-Ecuador

Introduction. Classically, pain management has been based on pharmacological therapies. The existence of non-pharmacological alternative therapies could potentially be an adjuvant in the analgesic management. The main limitation in relation to the potential use of alternative therapies is the lack of scientific evidence to analyze the effect of these therapies on pain management. This study aims to investigate the association between the application of sound waves in patients undergoing surgery with pain and stress levels. Objective. Compare levels of pain and stress among surgical patients who were exposed to sound waves and a control group. Method. Analytical cross-sectional study. 160 patients participated. Eighty patients received therapy with sound waves, in addition to treating pre and post surgical care and standardized for each surgical procedure, whereas the remaining 80 treated with standard pre- and post-surgical care only. The study was not blinded or randomized. Results. Using sound waves significantly reduced stress levels in the immediate postoperative (OR: 0.02, 95% CI 0.004 to .09) and 24 hours (OR: 0.19, 95% CI 0.04-1.0). The level of pain increased in both groups in the study period, however, the use of sound waves was associated with a statistical 80% decrease in the perception of some degree of pain at 24 hours post-surgery (OR: 0.21, 95 % CI from 0.09 to 0.51).Introducción. Clásicamente, el manejo del dolor ha sido basado en terapias farmacológicas. La existencia de terapias alternativas no farmacológicas podría, potencialmente, ser un adyuvante en el manejo analgésico. La principal limitación en relación al potencial uso de terapias alternativas, es la falta de evidencia científica que analice el efecto de dichas terapias en el manejo del dolor. El presente estudio pretende investigar la asociación entre la aplicación de ondas sonoras en pacientes sometidos a cirugías con los niveles de dolor y estrés. Objetivo. Comparar los niveles de dolor y estrés entre pacientes quirúrgicos a quienes se expusieron a ondas sonoras y un grupo control. Método. Estudio observacional transversal analítico. Participaron 160 pacientes. Ochenta pacientes recibieron la terapia con ondas sonoras, además del tratamiento y cuidado pre y post quirúrgico estandarizado para cada procedimiento quirúrgico, mientras que los restantes 80 recibieron el cuidado pre y post quirúrgico estándar solamente. El estudio no fue cegado, ni randomizado. Resultados. El uso de ondas sonoras disminuyó significativamente los niveles de estrés en el posquirúrgico inmediato (OR: 0.02, 95%IC 0.004-0.09), y a las 24 horas (OR: 0.19, 95%IC 0.04-1.0). El nivel de dolor incrementó en los dos grupos en el período estudiado, sin embargo el uso de las ondas sonoras estuvo asociado con una disminución estadística del 80% de la percepción de algún grado de dolor a las 24 horas posquirúrgicas (OR: 0.21, 95%IC 0.09-0.51)

Evaluación del comportamiento de dos especies forrajeras Marango (Moringa oleifera Lam.) y Leucaena (Leucaena leucocephala De Witt) en la fase de vivero en la Universidad Nacional Agraria, Managua

Con el objetivo de caracterizar el comportamiento inicial de Moringa oleifera y profundizar en las ventajas de esta especie, en comparación con otra forrajera de rápido crecimiento (Leucaena leucocephala); se llevo a cabo en el vivero de la Facultad de Recursos Naturales un ensayo con diseño completamente aleatorio con dos tratamientos, y 20 repeticiones. Se realizó un conteo diario de germinación por un periodo de tres semanas (21 días); mientras patrones de crecimiento fueron determinados a partir de evaluaciones semanales de diámetro basal y raíz, longitud de tallo y raíz, y numero de raíces secundarias; así como producción de biomasa expresada en peso seco y peso fresco de la parte área y radicular, de una muestra de 8 plantas destruidas semanalmente. Los resultados muestran ventajas de la especie M. oleifera para la mayoría de variables; solo superado en el número de raíces secundarias de L .leucocephala. Los valores relacionados a la calidad o potencial de establecimiento sugieren pocos problemas de establecimiento en campo para las especies M. oleifera y L. leucocephala como producto del rápido crecimiento, y aun con la desigual proporción en la relación tallo-raíz, y biomasa

A Quantitative Assessment of Forest Cover Change in the Moulouya River Watershed (Morocco) by the Integration of a Subpixel-Based and Object-Based Analysis of Landsat Data

A quantitative assessment of forest cover change in the Moulouya River watershed (Morocco) was carried out by means of an innovative approach from atmospherically corrected reflectance Landsat images corresponding to 1984 (Landsat 5 Thematic Mapper) and 2013 (Landsat 8 Operational Land Imager). An object-based image analysis (OBIA) was undertaken to classify segmented objects as forested or non-forested within the 2013 Landsat orthomosaic. A Random Forest classifier was applied to a set of training data based on a features vector composed of different types of object features such as vegetation indices, mean spectral values and pixel-based fractional cover derived from probabilistic spectral mixture analysis). The very high spatial resolution image data of Google Earth 2013 were employed to train/validate the Random Forest classifier, ranking the NDVI vegetation index and the corresponding pixel-based percentages of photosynthetic vegetation and bare soil as the most statistically significant object features to extract forested and non-forested areas. Regarding classification accuracy, an overall accuracy of 92.34% was achieved. The previously developed classification scheme was applied to the 1984 Landsat data to extract the forest cover change between 1984 and 2013, showing a slight net increase of 5.3% (ca. 8800 ha) in forested areas for the whole region

Recubrimientos necesarios en construcciones civiles con estructuras de acero para evitar la presencia de corrosión y mantenimientos estructurales

Trabajo de InvestigaciónEl acero en Colombia ha tomado mucha fuerza en las construcciones civiles del sector público y privado, el país está en vía de desarrollo viviendo procesos de evolución en varios aspectos, tanto a nivel económico, cultural, deportivo así como a nivel estructural; esto debido a varios factores como el aumento del poder adquisitivo, la inversión extranjera y nacimiento de nuevas empresas impulsando lo más novedoso en tecnología de construcción con acero. Bogotá como ciudad capital ha sido la pionera en adquirir estructuras hechas en acero su éxito ha sido gracias a su fácil fabricación, transporte y la disminución de tiempos en la intervención de la malla vial lo cual evita traumatismos a una ciudad con 7´878.783 habitantes aproximadamente, este tipo de construcciones lo ha tomado como ejemplo en el país grandes ciudades como lo son Medellín, Cali, Barranquilla, Cartagena entre otras. Las diferentes condiciones atmosféricas de cada ciudad del país afectan las estructuras que son construidas con acero principalmente por la variación de humedad relativa. Debido a los diferentes tipos de fenómenos naturales es muy importante analizar los tipos de corrosión que se presentan en estructuras como puentes vehiculares, peatonales, estaciones de transporte masivo, paraderos, postes de alumbrado público y demás estructuras que por su temprano deterioro puedan afectar el normal funcionamiento de las ciudades del país.PregradoIngeniero Civi

Interacciones tierra–aire y el transporte de calor en el subsuelo: el papel de los forzamientos externos e implicaciones para la reconstrucción de temperaturas del último milenio

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Físicas, Departamento de Física de la Tierra y Astrofísica, leída el 16/02/2021The energy exchanges at the land-atmosphere interface play a fundamental role in several weather and climatic processes both in the atmosphere and below the land surface. A part of the radiation that reaches the surface is reflected away or dissipated by sensible and latent heat fluxes back to the atmosphere while the ground heat flux balances the excess of incoming energy. This surface energy balance establishes a link between the atmosphere and the ground surface that often translates into a strong coupling between the surface air temperature (SAT) and the ground surface temperature (GST). In turn, the surface temperature stands as the key variable since it aects the amount of heat owing into the soil through thermal conduction, thus controlling the distribution of temperature below thesurface. The coupling between SAT and GST and the conductive heat transport of the surface temperature into the soil stand as the central assumptions for reconstructing the past surface temperature variations from present-day subsurface temperature measurements in a technique known as borehole reconstructions. As with every type of temperature reconstruction method, the borehole technique is subject to uncertainty sources principally due to the inuence of physical processes at the surface that interrupt the SAT{GST coupling assumption over adiversity of temporal scales. Understanding the physical mechanisms behind such processes is crucial to gain con dence in the borehole technique estimates regarding the past SAT variations...Los intercambios de energía en la interface suelo-atmosfera juegan un papel fundamental en numerosos procesos meteorológicos y climáticos tanto en la atmosfera como bajo la super cie. Una parte de la energía que impacta la superficie es reflejada o disipada mediante flujos de calor sensible y latente mientras que el exceso de energía incidente es balanceado a través del flujo de calor hacia el suelo. Este balance de energía en la super cie establece un vínculo entre la atmosfera y la superficie terrestre que generalmente se traduce en un fuerte acoplamiento entre la temperatura superficial del aire (SAT por sus siglas en ingles) y la temperatura de la super cie del suelo (GST por sus siglas en ingles). A su vez, la temperatura de la superficie se establece como la variable fundamental, ya que afecta a la cantidad de energía que fluye hacia el suelo mediante conducción térmica, por lo que influencia la distribución de temperaturas en el suelo. El acoplamiento entre SAT y GST, sumado al transporte de energía conductivo de la temperatura superficial hacia el suelo, representan las hipótesis centrales para reconstruir la temperatura superficial del pasado usando perfiles de temperatura del subsuelo (BTP por sus siglas en ingles) actuales. Al igual que todos los métodos de reconstrucción de la temperatura, esta técnica también esta sujeta a fuentes de incertidumbre, que principalmente se dan por la influencia de algunos procesos físicos en la superficie que interrumpen el acoplamiento entre SAT y GST a diferentes escalas temporales...Fac. de Ciencias FísicasTRUEunpu

The quorum sensing system and the stationary phase RpoS sigma factor of the onion pathogen <i>Burkholderia cepacia</i> Gv 1 type strain, ATCC 25416

Bacterial strains belonging to Burkholderia cepacia can be human opportunistic pathogens, plant growth promoting and have remarkable catabolic activity. Recently, B. cepacia has been thus far subdivided into several Genomovars comprising what is now known as the B. cepacia complex. In this thesis, the quorum sensing system of a rot onion Genomovar I type strain, ATCC 25416 is described. Quorum sensing is a cell-density dependent regulatory response, which involves the production of A-acyl homoserine lactones signal molecules (HSLs). The cep locus of B. cepacia ATCC 25416 coding for LuxI family CepI and LuxR family CepR proteins has been identified and characterised. The two genes have been inactivated in the chromosome and shown that CepI is responsible for the biosynthesis of a C6-HSL and a C8-HSL and that the cep locus regulates protease production as well as onion pathogenicity. A cep-lacZ based sensor plasmid has been constructed and used to demonstrate that CepR was specific for C8-HSL and not for C6-HSL, that a cepR knock out mutant synthesised 70 % less HSLs and that CepR had a higher specificity towards long chain HSLs. With the aid of this sensor plasmid, a novel technique aimed to identify quorum sensing-controlled (QSC) genes in B. cepacia is described. In addition, the cloning and characterization of the stationary phase sigma factor gene rpoS of B. cepacia ATCC 25416 is also described. This RpoS was found to be 74 % identical to the RpoS of Ralstonia solanacearum but rather distant from other RpoS of gram-negative y-Proteobacteria. It was established that quorum sensing in B. cepacia has a negative effect on rpoS expression as determined using an rpoS-lacZ transcriptional fusion; on the other hand, rpoS-null mutants displayed no difference in the accumulation of HSL signal molecules

Disfuncionalidad familiar y su relación con la conducta delictiva

La disfunción familiar se establece como el patrón de conductas desadaptativas, presentes en uno o varios integrantes de una determinada familia que permite una influencia determinante en el entorno global familiar. Mediante este inadecuado comportamiento se contribuye a la obliteración del crecimiento individual de uno o varios de los integrantes, alterando la capacidad de sana interrelación entre los miembros, cuyo efecto a futuro tendrá un impacto en la interrelación con la sociedad, siendo una de los resultados mas latentes la generación de actitudes delictivas que terminan por afectar ya no solo el núcleo familiar si no a la comunidad de la cual es participe el o los miembros de la “familia disfuncional”, es por tal razón una prioridad el abordar su complejidad, mas aun en medio de esta creciente ola de violencia y criminalidad en diferentes países, donde la propia migración ha generado el resquebrajamiento de muchas familias por diferentes razones sociales. Es así que se ha hecho una selección exhaustiva de estudios recientes que nos permiten profundizar en esta problemática, intentando ver la relación existente entre la “disfuncionalidad familiar” y la “acción delictiva” a partir de experiencias diversas y que nos brindan una conclusión clarificante que puede ayudar a considerar no solo la acción de los profesionales si no la toma de propuestas a nivel de la gestión pública con una mirada mas integral.Family dysfunction is established as the pattern of maladaptive behaviors, present in one or more members of a certain family that allows a determining influence in the global family environment. This inappropriate behavior contributes to the obliteration of the individual growth of one or more of the members, altering the ability of healthy interrelation between the members, whose effect in the future will have an impact on the interrelation with society, being one of the most latent the generation of criminal attitudes that end up affecting not only the family nucleus but the community in which the member or members of the "dysfunctional family" participates, it is for this reason a priority to address its complexity, even more in the midst of this growing wave of violence and crime in different countries, where migration itself has generated the breakdown of many families for different social reasons. Thus, an exhaustive selection of recent studies has been made that allows us to delve into this problem, trying to see the relationship between "family dysfunctionality" and "criminal action" from diverse experiences and that provide us with a clarifying conclusion that It can help to consider not only the action of professionals but also the taking of proposals at the level of public management with a more comprehensive perspective.Tesi