Problemas de control en procesos de eutrofización

El aumento de los niveles de nitrógeno y fósforo (nutrientes principales para determinadas algas) en grandes masas de agua debido a la acción contaminante del hombre, puede traer consigo una disminución de la calidad del agua (procesos de eutrofización). En este trabajo estudiamos un m´etodo de control de esta clase de procesos, basado en el uso de biorreactores (tanques en donde se desarrollarán una serie de procesos que reducirán los niveles de nitrógeno y/o fósforo del agua por debajo de unos umbrales máximos). Matemáticamente estos métodos de control se pueden formular como problemas de control óptimo con restricciones sobre el estado en donde las ecuaciones de estado son un tipo de sistema de ecuaciones cuasilineales

Raw materials and provenance areas of the lithic industry from the lower paleolithic open air settlement of Río Iro and Arroyo de la Cueva (Chiclana, Cádiz, Spain)

Análisis de materiales no trabajados en yacimientos al aire libre en Río Iro y Arroyo de la Cueva

Exploring and correcting the bias in the estimation of the Gini measure of inequality

The Gini index is probably the most commonly used indicator to measure inequality. For continuous distributions, the Gini index can be computed using several equivalent formulations. However, this is not the case with discrete distributions, where controversy remains regarding the expression to be used to estimate the Gini index. We attempt to bring a better understanding of the underlying problem by regrouping and classifying the most common estimators of the Gini index proposed in both infinite and finite populations, and focusing on the biases. We use Monte Carlo simulation studies to analyse the bias of the various estimators under a wide range of scenarios. Extremely large biases are observed in heavy-tailed distributions with high Gini indices, and bias corrections are recommended in this situation. We propose the use of some (new and traditional) bootstrap-based and jackknife-based strategies to mitigate this bias problem. Results are based on continuous distributions often used in the modelling of income distributions. We describe a simulation-based criterion for deciding when to use bias corrections. Various real data sets are used to illustrate the practical application of the suggested bias corrected procedures.Regional Government of Andalusia and the European Regional Development Fund (project P18-RT-576)Grants of the University of Granada (Unidad Científica de Excelencia “Desigualdad, Derechos Humanos y Sostenibilidad – DEHUSO” del Plan Propio; and Programa de Ayudas a la revisión de textos científicos de la Facultad de Ciencias Económicas y Empresariales

Single Imputation Methods and Confidence Intervals for the Gini Index

This research has been partially supported by the Ministry of Economy, Industry and Competitiveness, the Spanish State Research Agency (SRA) and European Regional Development Fund (ERDF) (project reference ECO2017-86822-R). This research has been partially supported by the Ministry of Economy, Industry and Competitiveness, the Spanish State Research Agency (SRA) and European Regional Development Fund (ERDF) (project reference ECO2017-84138-P).The problem of missing data is a common feature in any study, and a single imputation method is often applied to deal with this problem. The first contribution of this paper is to analyse the empirical performance of some traditional single imputation methods when they are applied to the estimation of the Gini index, a popular measure of inequality used in many studies. Various methods for constructing confidence intervals for the Gini index are also empirically evaluated. We consider several empirical measures to analyse the performance of estimators and confidence intervals, allowing us to quantify the magnitude of the non-response bias problem. We find extremely large biases under certain non-response mechanisms, and this problem gets noticeably worse as the proportion of missing data increases. For a large correlation coefficient between the target and auxiliary variables, the regression imputation method may notably mitigate this bias problem, yielding appropriate mean square errors. We also find that confidence intervals have poor coverage rates when the probability of data being missing is not uniform, and that the regression imputation method substantially improves the handling of this problem as the correlation coefficient increases.Ministry of Economy, Industry and Competitiveness Spanish State Research Agency (SRA)European Commission ECO2017-84138-

Estrés oxidativo y osteonecrosis de la cabeza femoral

La osteonecrosis no traumática de la cabeza femoral representa un problema clínico importante, ya que hasta un 80% de los casos terminan en un colapso osteocondral con gran destrucción ósea y daño articular, con dolor y pérdida de la función de la cadera, necesitando finalmente una intervención de prótesis de sustitución a una edad temprana. La patogénesis de esta enfermedad es multifactorial y se conocen diversidad de factores etiológicos asociados a ella: consumo de alcohol y tabaco, uso de costicosteroides, alteraciones hemostáticas, alteraciones en el metabolismo lipídico y presencia de ciertos polimorfismos genéticos. Sin embargo, un gran número están descritas como idiopáticas y no presentan factores de riesgo. Recientes estudios en modelos animales de ONF inducida por esteroides sugieren que el estrés oxidativo podría estar involucrado en el desarrollo de la enfermedad. Estos estudios muestran que la administración de sustancias oxidantes aumenta el riesgo de padecer la enfermedad y que la administración de antioxidantes podría prevenir el desarrollo de la misma.Non-traumatic osteonecrosis of the femoral head represents a significant clinical problem. Chondral collapse occurs in up to 80% of the untreated cases resulting in bone destruction, pain and loss of joint function and prosthetic hip replacement at an early age is needed. The pathogenesis of the disease is likely multifactorial and seve- ral etiologic factors are known to be associated with it: alcohol intake, smoking, corticosteroid use, impaired hemos- tasis and lipid metabolism, and the presence of certain polymorphisms. However, a significant number are described, as idiopathic and do not present any risk factor. Recent studies in steroid-induced ONF animal models suggest that oxidative stress could be involved in the development of the disease. These studies show that the administration of pro-oxidant substances increase the risk of disease and antioxidants administration might prevent the development thereo

Rescaled bootstrap confidence intervals for the population variance in the presence of outliers or spikes in the distribution of a variable of interest

Confidence intervals for the population variance in the presence of outliers or spikes in the distribution of a variable of interest are topics that have not been investigated in depth previously. Results derived from a first Monte Carlo simulation study reveal the limitations of the customary confidence interval for the population variance when the underlying assumptions are violated, and the use of alternative confidence intervals is thus justified. We suggest confidence intervals based on the rescaled bootstrap method for many reasons. First, this is a simple technique that can be easily applied in practice. Second, it is free of probabilistic distributions. Finally, it can be easily applied to the cases of finite populations and samples selected from complex sampling designs. Results derived from a second Monte Carlo simulation study indicate that the suggested confidence intervals have desirable coverage rates with smaller average widths. Accordingly, an advantage of the suggested confidence intervals is that they offer a good compromise between simplicity and desirable properties. The various simulation studies are based on different scenarios that may arise in practice, such as the presence of outliers or spikes, and the fact that the underlying assumptions of the customary confidence interval are violated

Plantas transgénicas con alto rendimiento en peso seco y almidón cuyos órganos de reserva presentan elevada textura, elevado contenido en almidón y elevado rendimiento en peso seco

Plantas transgénicas con alto rendimiento en peso seco y almidón cuyos órganos de reserva presentan elevada textura, elevado contenido en almidón y elevado rendimiento en peso seco. La presente invención proporciona plantas transgénicas con alto rendimiento en peso seco y almidón cuyos órganos de reserva presentan elevada textura, elevado contenido en almidón y elevado rendimiento en peso seco.Peer reviewedUniversidad Pública de Navarra OTRI, Consejo Superior de Investigaciones Científicas (España)B1 Patente sin examen previ

Optical imaging spectroscopy for rapid, primary screening of SARS-CoV-2: a proof of concept

Effective testing is essential to control the coronavirus disease 2019 (COVID-19) transmission. Here we report a-proof-of-concept study on hyperspectral image analysis in the visible and near-infrared range for primary screening at the point-of-care of SARS-CoV-2. We apply spectral feature descriptors, partial least square-discriminant analysis, and artificial intelligence to extract information from optical diffuse reflectance measurements from 5 µL fluid samples at pixel, droplet, and patient levels. We discern preparations of engineered lentiviral particles pseudotyped with the spike protein of the SARS-CoV-2 from those with the G protein of the vesicular stomatitis virus in saline solution and artificial saliva. We report a quantitative analysis of 72 samples of nasopharyngeal exudate in a range of SARS-CoV-2 viral loads, and a descriptive study of another 32 fresh human saliva samples. Sensitivity for classification of exudates was 100% with peak specificity of 87.5% for discernment from PCR-negative but symptomatic cases. Proposed technology is reagent-free, fast, and scalable, and could substantially reduce the number of molecular tests currently required for COVID-19 mass screening strategies even in resource-limited settings.Ministerio de Ciencia e Innovación, 2020 Emergency Call for Research Projects about the SARS-CoV-2 virus and the COVID-19 disease Instituto de Salud Carlos III by Grant Number EQC2019-006240-PComisión Europea, Joint Research Center (JRC) HUMAINT project

Novedades de la Prehistoria de Ceuta. Resultados científicos de la carta arqueológica.

Artículo sobre los resultados de la carta arqueológica realizada en Ceuta. Síntesis de los resultados

Software architecture for customized physical exercise prescription

En la actualidad existe una gran cantidad de aplicaciones para la realización de ejercicio físico. En este artículo se presenta una arquitectura software para una aplicación que permite la prescripción de ejercicios físicos personalizados. Esta arquitectura incluye dos funcionalidades, la funcionalidad para el especialista que prescribe el ejercicio y la funcionalidad para el usuario que debe seguir esta prescripción. La interacción entre el especialista y el usuario se realiza mediante el envío de eventos. Especialistas (médicos/fisioterapeutas/educadores físicos) pueden indicar los ejercicios adecuados en cada caso. Esta aplicación permitirá a los usuarios con demanda de atención personalizada mejorar la condición física y la calidad de vida. Los usuarios podrán realizar el ejercicio físico de forma autónoma, sin tener que realizar desplazamientos y en un horario flexible.Currently there is a lot of available applications to do physical exercise. This article describes the software architecture for an application that allows customized exercise prescription. This architecture includes two functionalities, the functionality that allows specialists to prescribe physical exercises and the functionality for users who must follow this prescription. Interactions between specialists and users are allowed by means of sending events. Specialists (doctors, physiotherapists and physical educators) can indicate appropriate exercises in each case. This application will allow users with demand for personalized attention to improve their fitness and quality of life. Users can perform physical exercise autonomously, without having to travel and in a flexible schedule