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Dentro del panteón de las grandes series de televisión de las últimas décadas, sin duda The Wire (D. Simon & E. Burns, HBO, 2002-2006), ocupa un lugar destacado para la crítica y el público. The Wire, disfrazada de thriller policiaco, es un relato seriado que destaca por una estructura cíclica, unos arquetipos trágicos y una mirada coral que la diferencian del resto del contenido televisivo actual. Tres características (coralidad, tragedia y elementos cíclicos) que conforman la esencia del teatro griego. Y es que en cuanto nos detenemos a analizar The Wire vemos hasta qué punto los personajes y tramas de una de las series más prestigiosas de la historia, deben su esencia y su desarrollo a la cosmogonía y la mitología griega, soporte y alimento de toda nuestra cultura.

Altres ajuts: acords transformatius de la UAB Different causes can trigger imbalances on homeostatic mechanisms between intracellular and extracellular compartments resulting in abnormal blood potassium concentrations (hypo or hyperkalemia). This can lead to serious consequences, even a life-threatening situation. Early diagnosis, treatment and follow-up are essential to minimize critical impacts in patients. Bedside determination of blood potassium is not accessible in all health care centers or in all emergency departments and far less common in this kind of centers in emerging countries. We have therefore proposed a portable, economic and long-lifetime potentiometric point-of-care (POC) analytical microsystem to deal with this question. It is a continuous flow microfluidic platform, made of cyclic olefin copolymer (COC), which combines microfluidics and a detection system based on the potentiometric technique containing a potassium selective electrode with a novel composition of polymeric membrane, which improves lifetime. Its size is smaller than a credit card and shows a linear range of Nernst calibration equation from 1 to 26 mM K+, a detection limit of 0.16 mM K+, a satisfactory repeatability and reproducibility, and an analysis frequency of 20 samples h−1, requiring only 25 μL as sample volume. Moreover, lifetime is as long as 9 months by intensive use. All these features comply with medical requirements. Human serum samples were analyzed with the developed device and the obtained results were compared with those provided by two methods: ICP-OES and another using ion selective electrodes. No significant differences were observed, demonstrating the suitability of the developed POC microanalyzer for bedside health applications.

En 2018, la Organización Mundial de la Salud informó que los accidentes de tránsito se han convertido en un problema de salud pública, con muertes anuales estimadas en 1.2 millones de personas. En Colombia, constituyen la segunda causa de muerte en la población, sólo después de las derivadas de enfermedades crónicas. En la ciudad de Ibagué, seis de cada 100 000 habitantes mueren en las calles al año. En este trabajo estudiamos los puntos críticos de accidentabilidad de la ciudad, y encontramos como las causas principales las fallas mecánicas, así como las imprudencias y el estado de embriaguez de los conductores; asimismo, la inapropiada toma de decisiones y el desconocimiento de la forma de acceder a una glorieta (round point) se constituyen en un común denominador de accidentalidad.

A monolithic microfluidic free-flow electrophoresis device, fabricated using low-temperature co-fired ceramic technology, is presented. The device integrates gold electrodes and a 20 µm thick transparent ceramic optical window, suitable for fluorescence imaging, into a multilevel microfluidic chamber design. The microfluidic chamber consists of a 60 µm deep separation chamber and two, 50 µm deep electrode chambers separated by 10 µm deep side channel arrays. Fluorescence imaging was used for in-chip, spatial-temporal characterization of local pH variations in separation conditions as well as to characterize the separation process. The device allowed baseline resolution separation of a sample mixture of Fluorescein, Rhodamine 6G, and 4-Methylumbelliferone at pH 7.0, in only 6 s, using 378 V.s/cm. The results demonstrate the possibility of studying a chemical process using fluorescence imaging within the traditional fields of low-temperature co-fired ceramics technology, such as high-electrical-field applications, while using a simple fabrication procedure suitable for low-cost mass production.

[EN] Spontaneous resolution of pediatric obstructive sleep apnea (OSA) may stand behind the observed benefit of rapid maxillary expansion (RME), mainly supported by uncontrolled case series. We aimed to review the controlled, ideally randomized, evidence on the effectiveness of RME as compared to watchful waiting or alternative treatment of pediatric OSA. We only found one randomized clinical trial comparing RME with watchful waiting. The other four studies compared RME with the gold-standard treatment adenotonsillectomy, three of them in a non-randomized fashion. The results of the RCT showed no statistically significant differences in the enhancement of main (apnea hypopnea index, AHI) and secondary outcomes between RME and watchful waiting. Furthermore, reproducibility of the published studies was limited by insufficient description of their patients' inclusion criteria. We could not find convincing evidence of the benefit of RME over watchful waiting in patients with pediatric OSA. RCTs with reproducible inclusion criteria comparing RME with watchful waiting are still critically needed to support this intervention for the treatment of pediatric OSA. In the absence of solid evidence with RCT, RME should not be recommended for the treatment of pediatric OSA. PROSPERO REGISTRATION NUMBER: CRD42021249261. RUNNING SUMMARY: This systematic review explores the benefits of rapid maxillary expansion compared to spontaneous resolution of pediatric obstructive sleep apnea.

El objetivo de la presente investigación es desarrollar una herramienta de base tecnológica para el mejoramiento de la gestión y operación logística en las principales empresas distribuidoras de productos de consumo masivo de Ibagué. En particular, la investigación busca contribuir al mejoramiento de las principales decisiones del manejo de los inventarios, específicamente en la planeación de compras de los pedidos en las distribuidoras. Para el desarrollo de la investigación se establecen dos etapas. La primera denominada preliminar comprenderá la documentación problemática existente frente a la gestión de inventarios, al igual que los referentes teóricos para la fundamentación del desarrollo frente a la logística en sus diferentes enfoques para el sector empresarial. Por otra parte, la segunda etapa de desarrollo se estructurará en tres fases: Fase 1. Diagnóstico y caracterización en las principales empresas distribuidoras de productos de consumo masivo en Ibagué. Fase 2. Formular estrategias para identificar y seleccionar políticas de control de inventario. Fase 3. Generar una herramienta que permita establecer un modelo para mejorar la toma de decisiones. La administración de inventarios responde los problemas que surgen en las organizaciones sobre comprar y mantener existencias, formulando y respondiendo inquietudes del ¿qué?, ¿dónde?, ¿cuándo? y ¿cuánto? comprar, teniendo como principal objetivo la disminución de costos a través de la implementación de herramientas computacionales con diversos niveles de servicio que permitan determinar la situación más rentable (Ballou, 2004).

Altres ajuts: acords transformatius de la UAB A warning microanalyzer for the rapid monitoring of different heavy metals in water using Carbon Dots (CDs) as selective optical reagents is presented. The synthesized CDs have different surface functionalization and exhibit selective fluorescence quenching by heavy metal ions, that combined with the use of microfluidics, provide sensitivity, ease of automation and reproducibility to the method. Moreover, they present maximum excitation wavelengths around 350 nm, allowing multiparametric analysis with a single light source. Although quantum yields range from 16 % to 78 % depending on the type of CDs, enough sensitivity is achieved for each heavy metal using the same measurement conditions of the optical detection system (lock-in modulating frequency, signal amplitude and measurement frequency). The microanalyzer is composed of a Cyclic Olefin Copolymer (COC) analytical microsystem, a flow management system, and a miniaturized customized optical detection system. In this paper, we demonstrate that our proposed system can be used as a toxicity control system by selectively measuring five different heavy metal ions (Co, Cu, Hg, Ni, and Pb) with detection limits ranging from 2 to 12 ppb. Spiked tap water samples were analyzed, giving recoveries from 98 % to 134 %. Polluted samples containing four of the five heavy metal ions studied (Co, Cu, Ni, and Pb) were also analyzed with no significant differences observed between both methods, the proposed microanalyzer and the reference method (ICP-OES).

Altres ajuts: acords transformatius de la UAB Some inborn errors of metabolism and other diseases can result in increasing blood ammonium (hyperammonemia episodes), which can cause serious neurological complications in patients or even death. Early diagnosis, follow up and treatment are essential to minimize irreversible damages in brain. Currently, adequate analytical instrumentation for the necessary ammonium bedside determination is not available in all health centers but only in clinical laboratories of reference hospitals. We therefore have developed a low cost and portable potentiometric Point-of-Care microanalyzer (POC) to address this problem. It consists of a cyclic olefin copolymer-based microanalyzer, the size of a credit card and working in continuous flow, which integrates microfluidics, a gas-diffusion module and a potentiometric detection system. The analytical features achieved are a linear range from 30 to 1000 μmol L NH , a detection limit of 18 μmol L NH and a required sample volume of 100 μL, which comply with the medical requirements. Plasma and blood samples are analyzed with no significant differences observed between ammonium concentrations obtained with both the proposed microanalyzer and the reference method. This demonstrates the value of the developed POC for bedside clinical applications.

El Banco de la República (BanRep) genera información para la toma de decisiones, la rendición de cuentas y la difusión al público. En particular, el Reporte de Mercados Financieros está enmarcado dentro del principio de difusión al público y contribuye a cumplir con el servicio que presta el Banco de ofrecer información e investigación económica de calidad.

Proponemos nuevos modelos para el efecto de “El Nino Southern Oscillation”, ENSO, sobre los precios de los alimentos en Colombia. Estudiamos el efecto del “Oceanic Nino Index”, ONI, la medida de ENSO preferida, y de las precipitaciones locales sobre los precios de los alimentos perecederos. Estos modelos surgen de hechos estilizados conocidos, los cuales resumimos en este escrito, y admiten representaciones tiempo-variantes espacio-estado, de las que derivamos las reglas optimas de pronostico. Encontramos que una funcion de transferencia simple, condicional a la intensidad de ENSO, es suficiente para explicar estas relaciones. En adicion al bien conocido hecho que la Nina tiene un efecto distinto al del Nino sobre los precios de los alimentos, tambien hallamos que el efecto de ENSO cambia con su intensidad. Reconocer que el ONI es un indicador imperfecto de las condiciones climaticas locales mejora el ajuste de nuestro modelo, lo cual se refleja en sus pronosticos. El modelo para la precipitacion, sin embargo, no necesita de este recurso. Tambien surgen ganancias en eficiencia debido al modelamiento de la heterocedasticidad. Finalmente, estos modelos pueden servir para entender el efecto de ENSO en otras variables como el PIB.

El Banco de la República genera información para la toma de decisiones, la rendición de cuentas y la difusión al público. En particular, el Reporte de Mercados Financieros está enmarcado dentro del principio de difusión al público y contribuye a cumplir con el servicio que presta el Banco de ofrecer información e investigación económica de calidad.

espanolSe ha desarrollado y aplicado un metodo simplificado para reevaluar de forma mas precisa la seguridad al deslizamiento en seis presas de gravedad y contrafuertes en base a los resultados de modelos lineales numericos, verificando su validez mediante analisis no lineales y medidas experimentales. Se han llevado a cabo sondeos con recuperacion de testigo cercanos al tacon aguas arriba para inspeccionar posibles agrietamientos en las interfases hormigon-roca y se han instrumentado con extensometros para analizar los datos de aperturas. Los resultados obtenidos, demuestran que los criterios de diseno utilizados en los anos 50, en algunos casos no cubren el margen de incertidumbre esperado, respaldando asi la necesidad de revisar las grandes presas espanolas actualizando los analisis tal como rezan las Normas Tecnicas de Seguridad de Presas que recientemente ha aprobado el Gobierno. EnglishA simplified method has been developed and applied to reevaluate accurately sliding safety in six gravity and buttresses dams based on the results of numerical linear models. The method has been validated by nonlinear analysis and experimental measurements. Rotary boreholes have been drilled, with core recovery, close to the upstream face, to study the current state of the concrete-rock interface and a possible presence of cracks. Extensometers have been installed and cracks opening data has been analyzed. The results obtained show that the design criteria used in the 1950s, in some cases do not cover the expected margin of uncertainty. The need of reassessmenting of Spanish large dams is supported, updating data as Technical Standards for Dam Safety recently approved by the Government of Spain require.

Maestría en Educación y Desarrollo Humano, Facultad de Ciencias Sociales y Humanas. El presente trabajo de investigación tuvo como propósito caracterizar el acoso escolar y su relación con los roles que asumen los estudiantes de grado 9º de la institución Educativa Santa Teresita, municipio de La Victoria, Valle del Cauca, que se ven afectados por éste fenómeno, buscando identificar las situaciones relacionadas con el acoso escolar y las diferentes modalidades de acoso (físico, verbal, social) desde los roles de víctima, agresor o testigo. El trabajo está estructurado en cinco capítulos. El primero presenta las generalidades de la investigación: se describe y formula el problema, se propone la justificación y se plantean los objetivos. En el segundo plantea el Marco referencial, iniciando con el marco contextual a nivel geográfico e institucional, se muestran los antecedentes del trabajo de investigación y el marco teórico y legal. El tercer capítulo hace referencia a la metodología de trabajo, en donde emergen las categorías de análisis, el enfoque y tipo de investigación, la población muestra y las técnicas para la recolección y tratamiento de datos, así como el diseño metodológico. En el cuarto capítulo se presentan los resultados y análisis de las respuestas al cuestionario CIMEI y a lo obtenido del juego de roles y grupos focales practicado en los estudiantes. Finalmente, en el quinto capítulo se plantean las conclusiones. Metodológicamente se usa la narrativa desde los estudiantes que configuran el concepto de acoso escolar y que pueden establecer cusas, roles y consecuencias del mismo, teniendo presente que en el diario acontecer escolar surgen relatos enriquecedores para la comprensión de este fenómeno de estudio. Recogiendo las afirmaciones de los estudiantes se hace todo el análisis de los hechos configurados como acoso escolar, se estudian los diferentes roles: agresor, víctima y espectador, con su respectiva caracterización y se hace una reflexión sobre las posibilidades de enfrentar la problemática que afecta a toda la comunidad escolar.

Innovation in products and processes, traceability, food security and quality control are inherent challenges in agri-food sector. Trends in wine production are focused on obtaining natural wines with less chemical intervention. Following this goal, a low cost miniaturized, easy-to-use and highly automated microanalyzer to monitor total potassium in winemaking processes is presented. The microsystem monolithically integrates microfluidics as well as a potentiometric detection system and does not require any sample pretreatment. The analytical features provided are a linear range from 250 to 4000 mg L-1 K+, covering all the concentrations expected in must and wine samples, a detection limit of 75 ± 12 mg L-1 K+, and an adequate reproducibility and repeatability. Sample throughput is calculated at 20 h−1 with a waste volume generation lower than 4 mL per analysis. The microsystem lifetime is at least 4 months. Different wine and grape juice samples have been analyzed reaching outstanding results.

El comportamiento de los precios de los alimentos en Colombia ha sido un factor que inquieta a la autoridad monetaria por su volatilidad, alta ponderacion en la canasta de IPC y en ocasiones recurrentes altos niveles debido a su reaccion a choques de oferta como el clima, lo cual dificulta la tarea de estabilizar la inflacion alrededor de la meta. De lo anterior, se desprende la necesidad de tener pronosticos insesgados y mas oportunos de los cambios en el precio de los alimentos en el corto plazo. En este documento se desarrolla una metodologia que aprovecha la informacion disponible con alta frecuencia de precios y abastecimiento de alimentos y permite combinar informacion observada en varias frecuencias para generar pronosticos alternativos de la variacion de los precios de los alimentos y sus diferentes componentes. Los resultados encontrados indican que los modelos propuestos de frecuencias mixtas, producen mejores pronosticos que los tradicionales que utilizan solamente informacion de precios del Sistema de Informacion de Precios del Sector Agropecuario (SIPSA-DANE).

En este documento se presenta una caracterizacion de los fenomenos meteorologicos de El Nino y La Nina, y una descripcion de sus principales efectos sobre la inflacion en Colombia. Estos episodios climaticos se vienen presentando desde hace siglos en el territorio nacional, generando cambios en el nivel de temperaturas y precipitaciones en la mayor parte del territorio colombiano, sin que hayan tenido historicamente un patron regular de ocurrencia y de intensidad. Durante la ocurrencia de El Nino se destaca el efecto negativo sobre el sector agropecuario, que impacta fuertemente los precios de la canasta de alimentos y en menor medida la inflacion anual al consumidor. A pesar de la no sistematicidad en la ocurrencia de estos eventos climaticos, la inflacion de alimentos, la inflacion al consumidor y el precio relativo de los alimentos muestran comportamientos alcistas durante la ocurrencia de El Nino. Durante La Nina se presenta una disminucion de los precios al consumidor. El precio relativo de los alimentos muestra disminuciones al concluir cualquiera de los dos fenomenos.

Introducción: Los escasos análisis científicos de partidos y procesos de entrenamiento en mujeres futbolistas contrastan con la creciente popularidad del fútbol femenino. Objetivo: Describir las variables espaciotemporales del patrón de carrera desarrollado en superficie natural y artificial por mujeres futbolistas profesionales. Método: Se realizó un estudio de corte transversal, en diecinueve (n=19) deportistas profesionales con una media de 22,3 años, a quienes se les evaluaron las variables espaciotemporales de la carrera en un campo de juego de superficie natural (Bermuda 419) y artificial (Star 2) a través de un sistema de medición óptico (Opto Gait). Resultados: En la superficie natural, la velocidad y la cadencia de las futbolistas fueron superiores; en la artificial, resultaron ser mayores la energía, el tiempo de vuelo, la fase de contacto y el ángulo de paso (p< 0.05). Por otra parte, se observó una relación indirecta entre la velocidad, el tiempo de contacto, el porcentaje y el peso graso (p=0,01). Conclusión: Nuestros resultados sugieren que la superficie natural, Bermuda 419, permite un patrón de carrera más rápido, caracterizado por un menor uso de energía, tiempo de vuelo, fase de contacto y ángulo de paso. Introduction: The scarce scientific analysis of matches and training processes in women soccer players contrast with the growing popularity of women's football. Objective: To describe the spatio-temporal variables of the career pattern developed on natural and artificial surfaces by professional female soccer players. Method: A cross-sectional study was carried out, in nineteen (n = 19) professional athletes with an average of 22.3 years, who were evaluated the spacetime variables of the race in a natural surface playing field (Bermuda 419 ) and artificial (Star 2) through an optical measurement system (Opto Gait). Results: On the natural surface, the speed and cadence of the soccer players were superior; in the artificial one, the energy, the flight time, the contact phase and the passage angle (p

Resumen Introducción: En el mundo, 5,4 millones de personas fallecen al año por enfermedades relacionadas con el tabaco, y es la adolescencia una de las etapas más vulnerables para desarrollar el hábito de fumar. Objetivo: Identificar factores asociados al inicio del consumo de tabaco en los estudiantes de la Pontificia Universidad Javeriana, Bogotá. Métodos: Se aplicó una encuesta de carácter voluntario, creada a partir del cuestionario de consumo de tabaco desarrollado por el Center of Desease Control and Prevention, a estudiantes de pregrado, mayores de edad, reclutados en los lugares de la Universidad más concurridos por fumadores. Resultados: La edad promedio de inicio del consumo en la muestra fue de 14,3 años (±1,9). Los factores más frecuentes fueron presión social (34,6 %), curiosidad (24,7 %) y estrés (17,6 %). Conclusión: La poca resistencia a la presión del entorno es la principal causa del inicio del hábito de fumar. Abstract Introduction: All over the world 5.4 million people die due to tobacco related diseases per year. Considering that teenagers are highly impressionable by media in tobacco consumption, they constitute the population of interest in order to diminish the use of tobacco and the morbidity associated with its use. Objective: To identify factors associated at the beginning of tobacco consumption. Methodology: Descriptive cross-sectional study using a poll created from a questionnaire on tobacco by Center of Disease Control and Prevention, with a sample of smokers, over 18, selected in the most popular smoking areas at Universidad Javeriana, Bogota – Colombia. Results: The most frequent factors related to the beginning of tobacco consumption were: Peer pressure (34.6%), curiosity (24.7%) and stress (17.6%). The average starting smoking age was 14.3 (±1.9). Conclusion The low capacity of opposing social pressure at parties and recreational events showed as the most important factor at the beginning of a smoking habit.

In this work, the influence of laser ablation and lamination parameters in the fabrication of embedded microstructures using Low Temperature Co-Fired Ceramics, have been studied. First, the influence of laser ablation parameters in the dimensions of fabricated microchannels in Low Temperature Co-Fired Ceramics substrates was characterized and strategies for tailoring the microchannels aspect ratios are described. The influence of lamination conditions on the fabrication of monolithically embedded microstructures is presented. Thereafter, a ceramic microfluidic platform, was constructed using a multilayer approach. The ceramic microfluidic platforms incorporate three independent inlet channels and a microfluidic chamber with an monolithically integrated transparent optical windows. The construction procedure used ensures monolithic ceramic devices with homogeneous surface chemistry as well as homogeneous physical properties. Fluorescence dyes were used in order to characterize the hydrodynamic focusing as a function of flow rate ratio of the microfluidic chamber inlets. The results obtained open the possibility of studying chemical process, in static or flow conditions using fluorescence imaging, within the traditional fields of LTCC technology, such as high-temperature or organic solvents applications, while using a simple fabrication procedure suitable for low cost mass production.

meso-Bromosubstituted indodicarbocyanine dyes produce dimeric molecules, together with the debrominated species, under acid catalysis. The relationship between the dimerization and hydrodebromination routes depends on the aryl substitution of the dyes. A possible reaction mechanism is also proposed.

Introducción: la creciente popularidad del fútbol femenino contrasta con la escasa evidencia científica de los partidos y procesos de entrenamiento de la mujer futbolista. Objetivo: analizar la velocidad y aceleración desarrollada en superficie natural por mujeres pertenecientes a un club de futbol profesional. Metodología: se hizo un estudio observacional de corte transversal con diecinueve (n=19) jugadoras, con una mediana de edad de 23 años (RIC: 18-25), a quienes se les analizaron las variables espaciotemporales durante el patrón de carrera desarrollado en superficie natural a través de un sistema de medición óptico (Opto Gait). Se utilizó la prueba de Kruskal Wallis para establecer las diferencias de velocidad y aceleración por posición de juego; así mismo, la prueba de Spearman para evaluar la relación entre las variables cuantitativas de interés. Se utilizó el software estadístico Stata versión 14.0 para el análisis de los datos. Se consideró un valor de p

A microanalyzer prototype for copper(II) ion monitoring in mining industrial processes is presented. The microanalyzer is designed as an assembly of different modules, each module being responsible for a unit operation. In order to optimize the industrial processes, the microanalyzer can automate all sample management, signal processing, and mathematical calculations and wirelessly transfer data to a control room. The determination of copper(II) ion is done using a colorimetric reaction and the microanalyser performs autocalibration by in situ dilution of a stock solution, matching the higher analyte concentration of the working range defined for the sample to be determined, using a multicommutation approach. The performance of the microanalyzer for monitoring copper(II) ion in water effluents of mining facilities was optimized in the working range from 1 to 10 mg/L to match Mexican environmental law regulations, which allow a maximum concentration of 4 mg/L of copper(II) ion in these circumstances.

La irrupción a principios de los años 90, de una nueva generación de directores, denominada “Joven Cine Español”, refrescó el panorama industrial y lo acercó de una manera singular y eficaz al público joven que abarrotaba las salas de exhibición en las postrimerías del milenio. El presentismo y el acercamiento a los géneros cinematográficos a la americana fueron según los historiadores las principales características de una generación que tiene en Alex de la Iglesia, Alejandro Amenábar o Fernando León de Aranoa a sus miembros más representativos. Aun no siendo un grupo homogéneo, ni formal ni ideológicamente, en sus óperas primas encontramos un elemento común y muy representativo: Madrid como escenario principal de sus tramas. Una ciudad que, por su capitalidad siempre fue el gran escenario del Cine Español, pero que en los años 90 se resignifica –nacional e internacionalmente - a través de la mirada de una generación que convierte a la Ciudad de Madrid, no solo en una localización de gran urbe moderna, sino en la materialización de un futuro distópico, en el umbral del propio Infierno o en un gran monstruo capitalista capaz de devorar las almas de todos sus habitantes. Un Madrid que son muchos. Que es, como siempre fue, los madriles.

The design, construction and evaluation of a low-cost cyclic olefin copolymer (COC)-based continuous flow microanalyzer with optical detection to determine the titratable acidity content of wine is here presented. The analysis method is based on the monitoring of the blue coloration decrease of a buffered bromothymol blue (BTB) solution in the presence of the acidic compounds of wine. The microanalyzer monolithically integrates the required microfluidic motifs as well as an optical flow cell where the measurements are performed by using a miniaturized and versatile photometric detection system. Fluid management is totally automated by the use of computer-controlled microvalves, permitting the automatic calibration of the system as well as the automatic sampling, including in-line dilution and analysis. The reduced size of the whole system along with its high simplicity and automation make it suitable for its application to the on-line monitoring of titratable acidity during wine-making processes. With the optimal conditions, a linear range up to 0.50 g L−1 tartaric acid, a quantification limit (LOQ) of 0.01 g L−1 and a detection limit (LOD) of 0.004 g L−1 were obtained, covering the most common acidity content of musts and wines. A sampling rate up to 26 h−1 could be achieved, consuming less than 3 mL of inexpensive reagents per analysis and requiring no pretreatment of the sample. The microsystem has been successfully applied to the quantification of the titratable acidity content of several wine samples, being the results in excellent agreement with the ones obtained by the reference method.

The analysis of soluble reactive phosphate (SRP) in water is key to control water quality. In order to continuous monitor orthophosphate content in water during treatment processes and in the effluents of wastewater treatment plants, conventional procedures, usually performed in a laboratory, must be adapted. This means pursuing efforts on miniaturizing systems to operate in situ and automating analytical methods to work on-line. The design, construction and evaluation of an automatic and low cost cyclic olefin copolymer (COC)-based spectrophotometric microanalyzer, capable of operating in unattended conditions, is presented to monitor soluble reactive phosphorous, as orthophosphate ion, in wastewater samples coming from sewage treatment plants. The microsystem, constructed by CNC micromilling and using a multilayer approach, integrates microfluidics to carry out the phosphomolybdenum blue (PMB) reaction and an optical flow-cell for the spectrophotometric orthophosphate determination in a single polymeric substrate smaller than a credit card. It is connected to a compact optical detection system composed by a LED emitting at 660 nm and a PIN-photodiode, both integrated in a PCB. Flow management is automatically performed by programmed microvalves and micropumps, which control autocalibration processes and allow unattended operation. Analytical features after the optimization of the microfluidic platform and the chemical and the hydrodynamic variables, were a linear range from 0.09 to 32 mg L−1 P and a detection limit of 0.03 mg L−1 P with a sampling rate of 24 samples h−1, demonstrating the microanalyzer suitability for SRP monitoring in water. Moreover, real samples were analyzed obtaining promising results.

The design, construction and evaluation of a low cost, cyclic olefin copolymer (COC)-based continuous flow microanalyzer, with optical detection, to monitor carbon dioxide in bottled wines and beers as well as in fermentation processes, is presented. The microsystem, constructed by computer numerically controlled (CNC) micromilling and using a multilayer approach, integrates microfluidics, gas-diffusion module and an optical flow-cell in a single polymeric substrate. Its size is slightly bigger than a credit card, exactly 45 × 60 × 4 mm in the microfluidic and diffusion module zone and 22.5 × 40 × 3 mm in the flow-cell zone. The gas-diffusion module is based on a hydrophobic polyvinylidene fluoride (PVDF) membrane, which allows the transfer of the carbon dioxide present in the sample to a bromothymol blue (BTB) pH-sensitive acceptor solution, where the color change is measured optically. The detection system consisted of a LED with an emission peak at 607 nm and a photodiode integrated in a printed circuit board (PCB). The obtained analytical features after the optimization of the microfluidic platform and hydrodynamic variables are a linear range from 255 to 10000 mg L−1 of CO2 and a detection limit of 83 mg L−1 with a sampling rate of 30 samples h−1.

The aim of this study was to determine the effect of sperm and seminal plasma (SP) on the freezability of porcine semen. Semen of eight commercial males from two farms in the central-western region of Colombia (four boars in each farm) was frozen and tested to select two males with high freezability (MHF) and two with low freezability (MLF), according to the percentage of functionally competent sperm (FCS). Immediately after the collection was completed, the SP and sperm from the males selected were separated by centrifugation to combine the two types of plasma with the two types of sperm, incubate them for three hours and then freeze them. The variables evaluated were: sperm morphology, structural and functional integrity of plasmatic membrane, progressive and total motility, DNA fragmentation, acrosome integrity, capacitated sperm and FCS. The combination of sperm and plasma of MHF recorded the highest value (P

The progress made in recent years in the area of micro total analysis system (μ-TAS) has allowed the development of analytical tools for determination and measurement of elements and compounds that previously required bench laboratory equipment for such purposes. μ-TAS provides a high degree of sensitivity and they are simple and affordable. This work details a process by which classical colorimetric methodologies used in analysis have been adapted from discontinuous to continuous flow systems, for determination of cobalt in aqueous solutions in real time. The purpose of this adaptation is the subsequent system miniaturization using low temperature co-fired ceramics (LTCC). The adapted methodology for the colorimetric determination of cobalt uses 3-Hydroxy-4-nitroso-2,7-naphtalene disulfonic acid disodium salt or nitroso-R salt (NRS) as the main reagent, in an environment of acetate and sodium citrate which favors the reaction. The carrier solution is prepared with sulfuric acid. The system encompasses a microfluidic structure in LTCC, a peristaltic pump to maintain the continuous flow, a six-way valve for sample injection, and an issuer of light of 540 nm based on a multiled. Using the integrated circuit TCS3414, the signal is sent to the computer wirelessly through zigbee protocol, and at the end a LabVIEW-based application shows the absorbance for a range of concentrations between 0.5 and 10 mg/L.

A boron trifluoride–methanol complex demonstrated remarkable deprotection selectivity against commonly used amino-protecting groups in the deacetylation of acetanilides and high sensitivity to the steric hindrance of substrates. The scope and limitations of the reaction were explored.

The successful integration of sample pretreatment stages, sensors, actuators and electronics in microfluidic devices enables the attainment of complete micro total analysis systems, also known as lab-on-a-chip devices. In this work, we present a novel monolithic autonomous microanalyzer that integrates microfluidics, electronics, a highly sensitive photometric detection system and a sample pretreatment stage consisting on an embedded microcolumn, all in the same device, for on-line determination of relevant environmental parameters. The microcolumn can be filled/emptied with any resin or powder substrate whenever required, paving the way for its application to several analytical processes: separation, pre-concentration or ionic-exchange. To promote its autonomous operation, avoiding issues caused by bubbles in photometric detection systems, an efficient monolithic bubble removal structure was also integrated. To demonstrate its feasibility, the microanalyzer was successfully used to determine nitrate and nitrite in continuous flow conditions, providing real time and continuous information.

Ultrasmooth gold/silver/gold trilayer nanostructured plasmonic sensors were obtained using commercial Blu-ray optical discs as nanoslits-based flexible polymer substrates. A thin gold film was used as an adhesion and nucleation layer to improve the chemical stability and reduce the surface roughness of the overlying silver film, without increasing ohmic plasmon losses. The structures were physically and optically characterized and compared with nanostructures of single gold layer. Ultrasmooth and chemically stable trilayer nanostructures with a surface roughness, Departament d'Universitats, Recerca i Societat de la Informació, Grant/Award Number: 2014 SGR 624; Ministerio de Economía y Competitividad, Grant/Award Number: SEV-2013-0295; Programa Estatal de investigación, desarrollo e innovación orientada a los Retos de la Sociedad, Grant/Award Number: TEC2016-78515-R; Spanish Ministry of Economy, Industry and Competitiveness (MINECO, Grant/Award Number: SEV2013-0295; CERCA programme/Generalitat de Catalunya; Departament d'Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya, Grant/Award Number: 2014 SGR 624; PreDICT project, Grant/Award Number: TEC2016-78515-R; CONACYT, Grant/Award Number: 225362

Introduction: All over the world 5.4 million people die due to tobacco related diseases per year. Considering that teenagers are highly impressionable by media in tobacco consumption, they constitute the population of interest in order to diminish the use of tobacco and the morbidity associated with its use. Objective: To identify factors associated at the beginning of tobacco consumption. Methodology: Descriptive cross-sectional study using a poll created from a questionnaire on tobacco by Center of Disease Control and Prevention, with a sample of smokers, over 18, selected in the most popular smoking areas at Universidad Javeriana, Bogota – Colombia. Results: The most frequent factors related to the beginning of tobacco consumption were: Peer pressure (34.6%), curiosity (24.7%) and stress (17.6%). The average starting smoking age was 14.3 (±1.9). Conclusion: The low capacity of opposing social pressure at parties and recreational events showed as the most important factor at the beginning of a smoking habit.

Introducción: Las Enfermedades Cardiovasculares son la principal causa de muerte y discapacidad a nivel mundial y en Colombia, siendo el riesgo cardiovascular la probabilidad que tiene un individuo de presentarlas. Existen múltiples modelos que intentan predecir la probabilidad de morbimortalidad debida a enfermedad cardiovascular en un tiempo determinado, sin embargo, hasta el momento, solo las escalas de PROCAM y Framingham 2008 han sido validadas en nuestro medio. En Colombia, son escasos los estudios que categoricen el riesgo cardiovascular poblacional y Santander hasta el momento no dispone de un estudio enfocado a categorizar el riesgo cardiovascular, desconociendo el perfil global del mismo. Objetivo: Determinar el perfil de riesgo cardiovascular y la mortalidad a 10 años mediante la utilización de la escala de Framingham calibrada para Colombia en población santandereana. Resultados: La población estudio se conformó por 577 personas de 30 a 64 años. La distribución por sexo fue predominantemente femenina (61,7%). Más de 2 tercios tenían como máximo nivel educativo primaria o secundaria, el 58,4% residía en área urbana. La prevalencia de los principales factores de riesgo fue 75,3% para sobrepeso/obesidad, 49,9% Hipercolesterolemia, 26,3% hipertensión arterial, 11% diabetes mellitus y 7,1% tabaquismo activo. Al aplicar la escala de Framingham calibrada para Colombia, se estimó una mediana de riesgo cardiovascular de 3,4% (2,1% mujeres y 5,9% hombres). La población evidenció un riesgo bajo en el 77,6%, intermedio 13,2% y alto en el 9,2%. No hubo una diferencia en el riesgo cardiovascular según el área de procedencia o estrato socioeconómico.Conclusiones: Se evidenció un riesgo cardiovascular global bajo, sin diferencias respecto al sexo o al área de residencia y se observó una dramática prevalencia de sobrepeso y obesidad, así como una tendencia de aumento de los demás factores de riesgo cardiovascular al ser comparados con los otros estudios departamentales o nacionales. 1. DESCRIPCIÓN DEL PROYECTO ............................................................................................... 14 1.1 PLANTEAMIENTO Y JUSTIFICACIÓN DEL PROBLEMA .................................................... 14 1.2 PREGUNTA DE INVESTIGACIÓN .................................................................................... 15 2. MARCO TEÓRICO Y ESTADO DEL ARTE ................................................................................. 17 3. OBJETIVOS ............................................................................................................................. 27 3.1 OBJETIVO PRINCIPAL ..................................................................................................... 27 3.2 OBJETIVOS SECUNDARIOS: ........................................................................................... 27 4. METODOLOGÍA PROPUESTA ................................................................................................ 29 4.1 TIPO DE ESTUDIO .......................................................................................................... 29 4.2 POBLACIÓN ................................................................................................................... 29 4.3 CRITERIOS DE SELECCIÓN ............................................................................................. 29 4.4 CALCULO DEL TAMAÑO DE MUESTRA .......................................................................... 29 4.5 MUESTREO .................................................................................................................... 31 4.6 RECOLECCIÓN DE LA INFORMACIÓN ............................................................................ 32 4.7 VARIABLES ..................................................................................................................... 33 4.8 ANÁLISIS DE DATOS ...................................................................................................... 36 4.9 CONSIDERACIONES ÉTICAS ........................................................................................... 36 5. RESULTADOS ................................................................................................................ 39 6. DISCUSIÓN ................................................................................................................... 47 7. CONCLUSIONES ............................................................................................................ 52 8. BIBLIOGRAFÍA ............................................................................................................... 54 Especialización Introduction: Cardiovascular Diseases are the main cause of death and disability worldwide and in Colombia, with cardiovascular risk being the probability that an individual has of presenting them. There are multiple models that attempt to predict the probability of morbidity and mortality due to disease cardiovascular disease in a given time, however, so far, only the PROCAM and Framingham 2008 scales have been validated in our setting. In Colombia, there are few studies that categorize cardiovascular risk population and Santander so far does not have a study focused on categorize cardiovascular risk, ignoring its global profile. Objective: To determine the cardiovascular risk profile and mortality at 10 years using the Framingham scale calibrated for Colombia in Santander population. Results: The study population consisted of 577 people aged 30 to 64 years. The distribution by sex was predominantly female (61.7%). More than 2 thirds had a primary or secondary educational level at most, 58.4% resided in the area urban. The prevalence of the main risk factors was 75.3% for overweight / obesity, 49.9% hypercholesterolemia, 26.3% arterial hypertension, 11% diabetes mellitus and 7.1% active smoking. When applying the Framingham scale calibrated for Colombia, a median cardiovascular risk of 3.4% was estimated (2.1% women and 5.9% men). The population showed a low risk in 77.6%, intermediate 13.2% and high in 9.2%. There was no difference in cardiovascular risk according to the area of ​​origin or socioeconomic stratum. Conclusions: A low global cardiovascular risk was evidenced, without differences with respect to sex or area of ​​residence and a dramatic prevalence of overweight and obesity, as well as an increasing trend of the other factors of cardiovascular risk when compared with the other departmental studies or national.

A novel and versatile optical reader for microfluidic platforms is presented. The reader includes a modular insertion port based on the lock and key concept for reproducible alignment with a miniaturized optical detection system comprising an interchangeable light emitting diode (LED) and a photodiode. The modular nature of the insertion port allows the use of microfluidic platforms in variable shapes and fluidic configurations. Three different analytical methodologies based on absorbance or fluorescence measurements were used to demonstrate the flexibility and reproducibility of the proposed experimental setup.

This work is focused on the design and implementation of a microsystem for continuous colorimetric determination of cobalt in aqueous solutions in real time. The main goal is the colorimetric determination of cobalt by adapting colorimetric methodologies used in discontinuous analysis systems to a continuous flow system and its subsequent miniaturization using the LTCC (Low Temperature Co-fired Ceramics) technology. The measure absorbance was recorded using an optical detection system based on a LED (Light Emitting Diode) with a wavelength of 540 nm.

Assisted reproductive technology (ART) can benefit from the features of microfluidic technologies, such as the automation of time-consuming labor-intensive procedures, the possibility to mimic in vivo environments, and the miniaturization of the required equipment. To date, most of the proposed approaches are based on polydimethylsiloxane (PDMS) as platform substrate material due to its widespread use in academia, despite certain disadvantages, such as the elevated cost of mass production. Herein, we present a rapid fabrication process for a cyclic olefin copolymer (COC) monolithic microfluidic device combining hot embossing—using a low-temperature cofired ceramic (LTCC) master—and micromilling. The microfluidic device was suitable for trapping and maturation of bovine oocytes, which were further studied to determine their ability to be fertilized. Furthermore, another COC microfluidic device was fabricated to store sperm and assess its quality parameters over time. The study herein presented demonstrates a good biocompatibility of the COC when working with gametes, and it exhibits certain advantages, such as the nonabsorption of small molecules, gas impermeability, and low fabrication costs, all at the prototyping and mass production scale, thus taking a step further toward fully automated microfluidic devices in ART.

The construction and evaluation of a Cyclic Olefin Copolymer (COC)-based continuous flow potentiometric microanalyzer to simultaneously monitor potassium, chloride and nitrate ions in samples from an on-board water recycling process expected to be installed in future manned space missions is presented. The main goals accomplished in this work address the specific required characteristics for a miniaturized on-line monitoring system to control water quality in such missions. To begin with, the integration of three ion-selective electrodes (ISEs) and a reference electrode in a compact microfluidic platform that incorporates a simple automatic autocalibration process allows obtaining information about the concentration of the three ions with optimal analytical response characteristics, but moreover with low reagents consumption and therefore with few waste generation, which is critical for this specific application. By a simple signal processing (signal removal) the chloride ion interference on the nitrate electrode response can be eliminated. Furthermore, all fluidics management is performed by computer-controlled microvalves and micropumps, so no manual intervention of the crew is necessary. The analytical features provided by the microsystem after the optimization process were a linear range from 6.3 to 630 mg L−1 and a detection limit of 0.51 mg L−1 for the potassium electrode, a linear range from 10 to 1000 mg L−1 and a detection limit of 1.58 mg L−1 for the chloride electrode and a linear range from 10 to 1000 mg L−1 and a detection limit of 3.37 mg L−1 for the nitrate electrode with a reproducibility (RSD) of 4%, 2% and 3% respectively. Sample throughput was 12 h−1 with a reagent consumptions lower than 2 mL per analysis.

The synthesis of a set of open-chain bis-aminosubstituted cyanine dyes as well as others with cyclic fragments in the polymethine chain is presented. These dyes are suitable for the development of polymeric compositions with variable optical characteristics as they can be covalently incorporated into the polymer.

All-ceramic microfluidic platforms with integrated optical microflow cells, fabricated using the low-temperature co-fired ceramics (LTCC) technology, are presented. The fabrication procedure described allows the construction of hermetically sealed monolithic microfluidic platforms, with homogeneous surface chemistry and physical properties. Therefore, the presented procedure eliminates the problems related to properties mismatch of the different construction materials used up to now to integrate transparent windows in the ceramic platforms. LTCC sheets, used as optical windows, were optically characterized in terms of transmittance according to their thickness in the UV–Vis–NIR regions. The influence of optical microflow cells parameters, such as optical path length, diameter, and window thickness, on sensitivity and detection limit, were investigated using the colorimetric complex [Fe(phen)3]2+ formed between Fe(II) and 1,10-phenanthroline. Detection limit as low as 8 ppb of Fe(II) was obtained. The results open the possibility of using optical detection within the traditional application fields of LTCC technology, such as high-temperature or organic solvents applications, while using a simple fabrication procedure suitable for low-cost mass production.

An optical microfluidic system based on the use of modified gold nanoparticles for monitoring Hg(II) is presented. The system is based on the specific recognition of the heavy metal by a new synthesized ionophore based on a modified thiourea, which is attached to the gold nanoparticles. This interaction generates a change on the gold Surface Plasmon Resonance (SPR) band. The sensitivity and selectivity of the procedure is firstly studied in batch. The obtained results demonstrate the mercury selective response over the different tested ions that can be found in environmental water samples. Due to the remarkable unusual rapid signal change observed during the interaction of the metal and the modified gold nanoparticles, the reaction can be easily performed in a microfluidic system. Results obtained by using the microfluidic system revealed improved analytical features compared to batch experiments such as a lower detection limit (11 ppb), higher sensitivity and faster analysis time, all this with an easy and automated procedure. Therefore, the approach has shown great potential for designing low cost instrumentation for automatic in-field discrete or continuous measurements of Hg(II).

An automated flow analyzer based on low temperature co-fired ceramic (LTCC), a solid-phase reactor (SPR) and a low-cost photometer was designed for ascorbic acid (AA) determination in pharmaceutical formulations. It consists of a peristaltic pump, three-way solenoid valves, SPR to chemically convert Cu(II) into Cu(I), and a LTCC device for mixing the liberated copper with bathocuproine and detection. The flow cell in the LTCC employed an ultrabright LED — photodiode photometer. The analyzer successfully determined AA in pharmaceutical formulations. The analytical curve from 8.5×10−6 to 7.0×10−4 M gave a detection limit of 7.0×10−7 M and a RSD of 2.1% for a 2.0×10−4 M AA solution (n = 10). A high sampling frequency of 102 h−1 and low reagent and sample consumption (150 µL) resulted.

The present paper describes the use of a microfluidic system to synthesize carbon dots (Cdots) and their use as optical pH sensors. The synthesis is based on the thermal decomposition of ascorbic acid in dimethyl sulfoxide. The proposed microsystem is composed of a fluidic and a thermal platform, which enable proper control of synthesis variables. Uniform and monodispersed 3.3 nm-sized Cdots have been synthesized, the optical characterization of which showed their down/upconversion luminescence and colorimetric properties. The obtained Cdots have been used for pH detection with down and upconverison fluorescent properties as excitation sources. The naked eye or a photographic digital camera has also been implemented as detection systems with the hue parameter showing a linear pH range from 3.5 to 10.2. On the other hand, experiments on the cytotoxicity and permeability of the Cdots on human embryonic kidney cells revealed their adsorption on cells without causing any impact on the cellular morphology. This work was supported by Projects SGR 2009-0323 from Catalonia Government and P10-FQM-5974 from the Junta de Andalucía (Spain). These projects were partially supported by European Regional Development Funds (ERDF). Our thanks to “Reincorporacion de Doctores UGR” programs and Greib startup

This work describes the development of a fully integrated Low Temperature Co-fired Ceramic (LTCC) microreactor for the synthesis of carbon dots (CDots). The microreactor integrates fluidics, a heating resistor and an optical window for fluorescence imaging of the reaction progress in a monolithic, all ceramic device, ensuring homogeneous surface chemistry and physical properties. A pool of different CDots was synthesized at high temperature and pressure using a hydrothermal method, demonstrating the robustness of the microreactor. The synthesis was monitored by following the photoluminescence of the produced CDots, and the reaction conditions were optimized according to their Quantum Yield (QY) and the flow pattern inside the microchannel. The obtained CDots exhibited blue photoluminescence upon irradiation with UV light with QYs of up to 0.77. The CDots were screened as metal nanoprobes and bioimaging contrast agents.

The construction and evaluation of a Low Temperature Co-fired Ceramics (LTCC)-based continuous flow potentiometric microanalyzer prototype to simultaneously monitor the presence of two ions (potassium and nitrate) in samples from the water recycling process for future manned space missions is presented. The microsystem integrates microfluidics and the detection system in a single substrate and it is smaller than a credit card. The detection system is based on two ion-selective electrodes (ISEs), which are built using all-solid state nitrate and potassium polymeric membranes, and a screen-printed Ag/AgCl reference electrode. The obtained analytical features after the optimization of the microfluidic design and hydrodynamics are a linear range from 10 to 1000 mg L−1 and from 1.9 to 155 mg L−1 and a detection limit of 9.56 mg L−1 and 0.81 mg L−1 for nitrate and potassium ions respectively.

La función administrativa de protección del patrimonio arqueológico con frecuencia conlleva pesadas cargas y un importante quebranto económico para los propietarios inmobiliarios. Tales cargas se traducen en concretas obligaciones de hacer y de soportar, que varían en función de la naturaleza del inmueble afectado y de los supuestos concurrentes. Así, la realización de obras en terrenos que gozan de una declaración formal de valor cultural, la constatación o presunción de restos arqueológicos o su hallazgo casual determinan en diferente medida la imposición de aquellas obligaciones arqueológicas. Ante la falta de una regulación sistemática sobre la materia en la legislación estatal y autonómica de patrimonio cultural, este trabajo analiza todas esas cargas arqueológicas y examina los diversos conceptos indemnizables y los mecanismos previstos para compensar el perjuicio sufrido.