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Propuesta para el tratamiento jurídico de los beneficios equitativos en la protección del patrimonio genético en el Ecuador

Esta tesis tiene como propósito investigar un área del Derecho que es nueva en el Ecuador y que lamentablemente ha sido poco practicada y aplicada. Nuestro país es un país mega diverso en donde se encuentran varios tipos de recursos genéticos y biológicos que desafortunadamente han sido mal aprovechados por terceros que los han explotado con el solo propósito de generar un beneficio único para ellos. Este inescrupuloso aprovechamiento ha dejado de lado al dueño de los recursos que es el Estado y a otros sujetos de derecho importantes, que han vivido de determinados recursos, tales como las comunidades y pueblos, quienes conocen al bien de tal manera que se ha vuelto parte de su tradición. La falta de normativa específica en el Ecuador, ha llevado a que varios recursos genéticos no sean respetados y que pese a que han servido de base para grandes invenciones e investigaciones, el Ecuador no ha sacado beneficio alguno de estos proyectos. Por consiguiente, la tesis que se presenta hace un estudio de la normativa ahora promulgada y como la misma puede ser aplicada correctamente en nuestro país, basándose en experiencia de países vecinos, para así poder obtener una repartición de beneficios justa y equitativa, sin perjuicio de los obstáculo constitucionales y legales que esto presente

Desarrollo y validación de un modelo predictivo del riesgo de infección basado en parámetros inmunológicos en receptores de trasplante renal

La infección constituye una de las principales causas de morbilidad y mortalidad entre receptores de trasplante renal (TR). Sin embargo, nuestra capacidad en el momento actual para identificar a los pacientes en riesgo de esta complicación es limitada. El desarrollo de un modelo ponderado de predicción basado en parámetros inmunológicos no patógeno-específicos y en variables clínicas permitiría individualizar el seguimiento y abordaje de estos pacientes en función de su riesgo específico de infección. Métodos: Análisis retrospectivo de una cohorte observacional prospectiva integrada por 447 pacientes sometidos a TR en nuestro centro entre noviembre de 2008 y marzo de 2013. Esta muestra global fue segmentada de forma aleatoria en una cohorte de derivación (292 pacientes) y una cohorte de validación (155 pacientes). Monitorizamos el recuento de subpoblaciones linfocitarias (linfocitos T CD3+, CD4+ y CD8+, linfocitos By linfocitos natural killer [NK]) y los niveles sé ricos de inmunoglobulinas y factores de complemento (C3 y C4) según un esquema preestablecido: momento basal (pre-trasplante), mes 1 y mes 6. El objetivo del estudio fue el desarrollo de infección global y bacteriana a lo largo de diversos periodos post-trasplante (precoz [primer mes], intermedio [meses 1 a 6) y tardío [a partir del mes 6]). Para la construcción de los modelos se realizaron varios análisis de regresión logística (según el periodo y tipo de infección), asignando un valor numérico a los coeficientes B así obtenidos. La capacidad de discriminación fue analizada mediante el área bajo la curva de características operativas del receptor (ROC); la exactitud diagnóstica mediante la estimación de sensibilidad, especificidad, y val ores predictivos positivo (VPP) y negativo (VPN); y la reproducibilidad y calibración mediante la cohorte independiente de validación. Resultados: No hubo diferencias en los parámetros inmunológicos basales en función del desarrollo de infección durante el primer mes post-trasplante, por lo que no se pudo construir ningún modelo para este periodo. El modelo de predicción de infección global durante el periodo intermedio se basó en los siguientes parámetros (evaluados al mes 1): edad del receptor ≥ 63 años (4 puntos), reintervención en el primer mes (3 puntos), función del injerto renal (-0,3 puntos por cada intervalo de 10 mL/ min), linfocitos T CD4+ 4 puntos observamos los siguientes valores: sensibilidad 54,8%, especificidad 83,2%, VPP 60,7% y VPN 79,5%. El modelo para infección bacteriana consistió, por su parte, en los siguientes parámetros: edad del receptor ≥ 65 años (3 puntos), retraso en la función del injerto (2 puntos), infección bacteria na previa (4 puntos), linfocitos NK 6,5 puntos obtuvimos: sensibilidad 54,4%, especificidad 85,4%, VPP 47,7% y VPN 88,4%. El modelo de predicción de infección global durante el periodo tardío incluyó los siguientes parámetros (evaluados al mes 6): enfermedad aterotrombótica (3 puntos), rechazo agudo previo (2 puntos), linfocitos NK 7 puntos observamos los siguientes valores: sensibilidad 69,2%, especificidad 64,3%, VPP 41,4% y VPN 85,2%. Por último, el modelo para infección bacteriana tardía consistió en: infección por VHC (3 puntos), rechazo agudo previo (3 puntos) y C3 4,5 puntos) arrojó los siguientes valores: sensibilidad 37,8%, especificidad 90,3%, VPP 45,2% y VPN 87,3%. La reproducibilidad y calibración de los modelos en la cohorte de validación fue buena. No hubo diferencias significativas en las áreas bajo la curva ROC ni en las incidencias de infección tras estratificar ambas cohortes por cuartiles o terciles del correspondiente modelo de predicción. Conclusiones: La combinación de parámetros inmunológicos no patógeno-específicos y ampliamente disponibles junto con una serie de variables clínicas seleccionadas permite predecir, en los meses 1 y 6 post-trasplante, el riesgo posterior de infección global o bacteriana en receptores de TR de forma individualizada

Automatic detection of traffic lights, street crossings and urban roundabouts combining outlier detection and deep learning classification techniques based on GPS traces while driving

The automatic generation of street networks is attracting the attention of research and industry communities in areas such as routable map generation. This paper presents a novel mechanism that focuses on the automatic detection of street elements such as traffic lights, street crossings and roundabouts which could be used to generate street maps and populate them with traffic influencing infrastructural elements such as traffic lights. In order to minimize the system requirements and simplify the data collection from many users with minimal impact for them, only traces of GPS data from a mobile device while driving are used. Speed and acceleration time series are derived from the GPS data. An outlier detection algorithm is used first in order to detect abnormal driving locations (which can be due to infrastructural elements or particular traffic conditions). Using deep learning, speed and acceleration patterns are automatically analyzed at each outlier in order to extract relevant features which are then classified into a traffic light, street crossing, urban roundabout or other element. The classification results are enhanced by adding the degree of atypicity for each point calculated as the percentage of times that a particular location is detected as an outlier in several drives. The proposed algorithm achieves a combined recall of 0.89 and a combined precision of 0.88 for classification.The research leading to these results has received funding from the “HERMES-SMART DRIVER” project TIN2013-46801-C4-2-R (MINECO), funded by the Spanish Agencia Estatal de Investigación (AEI), and the “ANALYTICS USING SENSOR DATA FOR FLATCITY” project TIN2016-77158-C4-1-R (MINECO/ ERDF, EU) funded by the Spanish Agencia Estatal de Investigación (AEI) and the European Regional Development Fund (ERDF)

Evaluation of outliers detection algorithms for traffic congestion assessment in smart city traffic data from vehicle sensors

On-board sensors in vehicles are able to capture real-time data representations of variables conditioning the traffic flow. Extracting knowledge by combining data from different vehicles, together with machine learning algorithms, will help both to optimise transportation systems and to maximise the drivers' and passengers' comfort. This paper provides a summary of the most common multivariate outlier detection methods and applies them to data captured from sensor vehicles with the aim to find and identify different abnormal driving conditions like traffic jams. Outlier detection represents an important task in discovering useful and valuable information, as has been proven in numerous researches. This study is based on the combination of outlier detection mechanisms together with data classification methods. The output of the outlier detection phase will then be fed into several classifiers, which have been implemented to assess if the multivariate outliers correspond with traffic congestion situations or not.The research leading to these results has received funding from the ‘1HERMESSMART DRIVER’ project TIN2013-46801-C4-2-R (MINECO), funded by the Spanish Agencia Estatal de Investigación (AEI), and the ‘ANALYTICS USING SENSOR DATA FOR FLATCITY’ project TIN2016-77158-C4-1-R (MINECO/ERDF, EU) funded by the Spanish Agencia Estatal de Investigación (AEI) and the European Regional Development Fund (ERDF). And the first author was supported by the MINECO Grant BES-2014- 070462

Testing the applicability of ambient noise methods in zones with different degree of anthropogenic sources

EGU2020: Sharing Geoscience Online, 4-8 may 2020The general objectives of the ¿Seismic Ambient Noise Imaging and Monitoring of Shallow Structures¿ (SANIMS) project, funded by the Spanish Ministry of Science, Research and Innovation (Ref.: RTI2018-095594-B-I00), are focused into the application and development of methods based on ambient noise seismic data recorded by dense networks to image and monitor natural and human-altered environments. To achieve this objective, temporal seismic networks have been installed since late 2019 in two very different settings; the Cerdanya Basin, a sedimentary basin located in the eastern Pyrenees and the city of Barcelona. Regarding the Cerdanya Basin, a relatively unaltered setting, a network of up to 25 broad-band stations has been installed for a period of one year. Additionally, a high resolution grid of seismic nodes will be deployed for 2 months in the central part of the basin, with interstation distances of 1.5 km. In order to constraint the uppermost crustal structure using ambient noise, vertical component recordings will be processed using the phase cross-correlation and time-frequency domain phase-weighted stacking to extract fundamental mode Rayleigh waves. The surface waves will then be used to measure inter-station group and phase velocity dispersion curves that will be inverted using the Fast Marching Surface Tomography method. Depending on data quality, we will also process the horizontal components to extract Love waves for joint inversions with Rayleigh waves to constrain radial anisotropy and/or the application of new strategies to perform attenuation tomography. Regarding areas strongly altered by human activity, we have deployed a network of 15 short-period stations within the city of Barcelona, in most of the cases installed in the basement of secondary schools, for a duration of 9-12 months. The objective of this deployment is twofold; acquire new valuable scientific data and introduce the students in an Earth Science research project. Although the Barcelona area has been investigated using MHVSR methods by different authors, the new data acquired by the SANIMS project will expand the available data and will allow to analyze the time variability of the measurements. This new dataset will also be used to analyze the applicability of the methods based on Rayleigh wave ellipticity inversion of ambient noise and earthquake data to provide S-velocity depth profiles. Under the assumption of an isotropic horizontally layered medium, the ellipticity inversion is not affected by the directivity of the diffusive noise wave field and seems therefore to be a good option to determine local S-velocity depth profiles in areas with little lateral inhomogeneities and uneven distribution of noise sources. We expect that the use of ambient noise methods will allow to map the basement and to obtain new higher resolution ambient noise tomographic images of the upper crust in the Cerdanya Basin and to better constrain the subsoil properties of Barcelona, hence improving the existing seismic hazard maps. Besides, comparing the results in both areas will allow to compare the performance of the different methods based on ambient noise in quiet and noisy areas

Experimental analysis of oscillatory premixed flames in a Hele-Shaw cell propagating towards a closed end

An experimental study of methane, propane and dimethyl ether (DME) premixed flames propagating in a quasi-two-dimensional Hele-Shaw cell placed horizontally is presented in this paper. The flames are ignited at the open end of the combustion chamber and propagate towards the closed end. Our experiments revealed two distinct propagation regimes depending on the equivalence ratio of the mixture as a consequence of the coupling between the heat-release rate and the acoustic waves. The primary acoustic instability induces a small-amplitude, of around 8 mm, oscillatory motion across the chamber that is observed for lean propane, lean DME, and rich methane flames. Eventually, a secondary acoustic instability emerges for sufficiently rich (lean) propane and DME (methane) flames, inducing large-amplitude oscillations in the direction of propagation of the flame. The amplitude of these oscillations can be as large as 30 mm and drastically changes the outline of the flame. The front then forms pulsating finger-shaped structures that characterize the flame propagation under the secondary acoustic instability. The experimental setup allows the recording of the flame propagation from two different points of view. The top view is used to obtain accurate quantitative information about the flame propagation, while the lateral view offered a novel three dimensional perspective of the flame that gives relevant information on the transition between the two oscillatory regimes. The influence of the geometry of the Hele-Shaw cell and of the equivalence ratio on the transition between the two acoustic-instability regimes is analyzed. In particular, we find that the transition to the secondary instability occurs for values of the equivalence ratio phi above (below) a critical value phi(c) for propane and DME (methane) flames. In all the tested fuels, the transition to the secondary instability emerges for values of the Markstein number M below a critical value M-c. The critical MarkstPublicad

The role of conductive heat losses on the formation of isolated flame cells in Hele-Shaw chambers

The propagation of low-Lewis-number premixed flames is analyzed in a partially confined Hele-Shaw chamber formed by two parallel plates separated a distance h apart. An asymptotic-numerical study can be performed for small gaps compared to the flame thickness deltaT . In this narrow-channel limit, the prob- lem formulation simplifies to a quasi-2D description in which the velocity field is controlled by domi- nant viscous effects. After accounting for conductive heat losses through the plates in our formulation, we found that the reaction front breaks into one or several isolated flame cells where the temperature is large enough to sustain the reaction, both in absence and in presence of buoyancy effects. Under these near-limit conditions, the isolated flame cells either travel steadily or undergo a slow random walk over the chamber in which the reacting front splits successively to form a tree-like pathway, burning only a small fraction of the fuel before reaching the end of the chamber. The production of quasi-2D circular or comet-like flames under specific favorable conditions is demonstrated in this paper, with convection, conductive heat losses and differential diffusion playing an essential role in the formation of the isolated one and two-headed flame cells.This work was supported by the project ENE2015-65852-C2-1-R (FV,MSS,DMR) and ENE2015-65852-C2-2-R (DFG,VK) (MINECO/FEDER, UE). Daniel Martínez-Ruiz would like to thank Amable Liñán for fruitful discussions

Mechanical thrombectomy during ischaemic stroke due to a calcified cerebral embolism

Carta al editor de Neurología, en la que los autores hacen el estudio de un caso al que han aplicado oclusión de la arteria cerebral media (ACM) por un émbolo cálcico tras cirugía de válvula aórtica, mediante neurointervencionismo.Letter to the editor of Neurology, in which the authors make the study of a case to which they have applied occlusion of the cerebral artery media (ACM) by a calcium embolus after aortic valve surgery, by neurointervention.peerReviewe

On the numerical modeling of terahertz photoconductive antennas

This paper shows the relevance of mobility models to describe the car- rier dynamics for the analysis of radiative semiconductor photoconductive devices in the terahertz regime. We have built a simulator that self-consistently solves the device physics and Maxwell’s equations to study the radiated fields. In particu- lar, we show a significant influence of an accurate description of the steady-state regime of the semiconductor device for calculating radiated electromagnetic fields in the broadside direction. Comparison with measurements shows the accuracy of our simulator and demonstrates the superior performance of numerical schemes based not only on the description of the carrier, electric potential, and field dis- tributions, but also on reliable local mobility models.This work was supported in part by the Spanish Ministry of Educa- tion under Project CSD2008-00068, the Junta de Andalucia Project P09-TIC-5327, the EU FP7/2007-2013, under grant 205294 (HIRF-SE project), and the Spanish National Project TEC2010-20841-C04-04