Dolor lumbar: calidad de vida

El dolor lumbar se ha constituido en uno de los problemas de salud más graves de la actualidad. Esta patología causa un gran impacto en las personas que la padecen, ya que provoca una discapacidad a la hora de realizar las actividades básicas de la vida diaria afectando en la calidad de vida. Tan reconocida es la frecuencia de las lumbalgias a nivel mundial, que se dice, que el 80% de la población ha padecido en algún momento de su vida dolor lumbar, generando un gran gasto socio sanitario, aunque no haya acudido a un servicio médico. Por eso se ha realizado una revisión bibliográfica, para conocer y valorar las alteraciones que produce el dolor en la calidad de vida de las personas con una patología lumbar, y posteriormente establecer los mecanismos más actuales y reconocidos para afrontar el dolor en este tipo de pacientes y con ello una mejora de la calidad de vida. La situación que más afecta en la calidad de vida el dolor lumbar es la incapacidad laboral temporal, seguidas de otras no menos importantes (síndrome de desacomodamiento motor, desconocimiento de su problema, afecciones en la vida social…). El principal mecanismo para afrontar esta patología debe ser la prevención desde la adolescenciaDepartamento de EnfermeríaGrado en Enfermerí

Some stylized facts of the Bitcoin market

In recent years a new type of tradable assets appeared, generically known as cryptocurrencies. Among them, the most widespread is Bitcoin. Given its novelty, this paper investigates some statistical properties of the Bitcoin market. This study compares Bitcoin and standard currencies dynamics and focuses on the analysis of returns at different time scales. We test the presence of long memory in return time series from 2011 to 2017, using transaction data from one Bitcoin platform. We compute the Hurst exponent by means of the Detrended Fluctuation Analysis method, using a sliding window in order to measure long range dependence. We detect that Hurst exponents changes significantly during the first years of existence of Bitcoin, tending to stabilize in recent times. Additionally, multiscale analysis shows a similar behavior of the Hurst exponent, implying a self-similar process.Fil: Fernández, Aurelio. Universitat Rovira I Virgili; España. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Basgall, María José. Universidad Nacional de la Plata. Facultad de Informatica. Instituto de Investigación En Informatica Lidi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hasperué, Waldo. Universidad Nacional de la Plata. Facultad de Informatica. Instituto de Investigación En Informatica Lidi; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Naiouf, Ricardo Marcelo. Universidad Nacional de la Plata. Facultad de Informatica. Instituto de Investigación En Informatica Lidi; Argentin

Transcritical Carbon Dioxide Charge-Discharge Energy Storage with Integration of Solar Energy

New and improved energy storage technologies are required to overcome non-dispatchability, which is the main challenge for the successful integration of large shares of renewable energy within energy supply systems. Energy storage is proposed to tackle daily variations on the demand side, i.e., storing low-price energy during off-peak or valley periods for utilization during peak periods. Regarding electrical energy storage, several technologies are available with different potentials for scalability, density, and cost. A recent approach for grid-scale applications is based on transcritical carbon dioxide charge and discharge cycles in combination with thermal energy storage systems. This alternative to pumped-hydro and compressed air energy storage has been discussed in scientific literature, where different configurations have been proposed and their efficiency and costs calculated. The potential of the concept has been demonstrated to be an economical alternative, including hybrid concepts with solar thermal storage. Even at low temperatures, the addition of solar energy has proved to be cost effective. This paper explores the effect of introducing solar-based high temperature heat on the performance of different configurations of “Transcritical carbon dioxide ‒ thermal energy storage system” cycles. A base-cycle with 8-hour discharge time is compared with different layouts. Discussions include details on the models, parametric analyses -including solar technology alternatives-, and simulation results. Round trip efficiency of the base case, without solar support and at pressure ratio of 9.4, is 52%. When solar input is considered, the efficiency is above 60%, increasing the turbine inlet temperature to 950 K. Estimated levelized cost of electricity values are in the range of pumped hydro and compressed air energy storage, 90-140 USD/MWh in agreement with other works on this thermal storage technology. The global analysis shows clear advantages for advancing in the study and definition of this technology for exploitation of synergies at different power ranges, integrated with mid/high temperature solar power plants and with smaller-scale renewable installations.Unión Europea. Fondo Europeo de Desarrollo Regional SOE1 / P3 / P0429E

Rotenone selectively occludes sensitivity to hypoxia in rat carotid body glomus cells

Carotid body glomus cells release transmitters in response to hypoxia due to the increase of excitability resulting from inhibition of O2 -regulated K+ channels. However, the mechanisms involved in the detection of changes of O2 tension are unknown. We have studied the interaction between glomus cell O2 sensitivity and inhibition of the mitochondrial electron transport chain (ETC) in a carotid body thin slice preparation in which catecholamine release from intact single glomus cells can be monitored by amperometry. Inhibition of the mitochondrial ETC at proximal and distal complexes induces external Ca2+-dependent catecholamine secretion. At saturating concentration of the ETC inhibitors, the cellular response to hypoxia is maintained. However, rotenone, a complex I blocker, selectively occludes the responsiveness to hypoxia of glomus cells in a dose-dependent manner. The effect of rotenone is mimicked by 1-methyl-4-phenylpyridinium ion(MPP+), an agent that binds to the same site as rotenone, but not by complex I inhibitors acting on different sites. In addition, the effect of rotenone is not prevented by incubation of the cells with succinate, a substrate of complex II. These data strongly suggest that sensitivity to hypoxia of carotid body glomus cells is not linked in a simple way to mitochondrial electron flow and that a rotenone (and MPP+)-sensitive molecule critically participates in acute oxygen sensing in the carotid body.Ministerio de Ciencia y Tecnología 1FD97–161

Evolving generalized euclidean distances for training RBNN

In Radial Basis Neural Networks (RBNN), the activation of each neuron depends on the Euclidean distance between a pattern and the neuron center. Such a symmetrical activation assumes that all attributes are equally relevant, which might not be true. Non-symmetrical distances like Mahalanobis can be used. However, this distance is computed directly from the data covariance matrix and therefore the accuracy of the learning algorithm is not taken into account. In this paper, we propose to use a Genetic Algorithm to search for a generalized Euclidean distance matrix, that minimizes the error produced by a RBNN.Publicad

Using a Mahalanobis-like distance to train Radial Basis Neural Networks

Proceeding of: International Work-Conference on Artificial Neural Networks (IWANN 2005)Radial Basis Neural Networks (RBNN) can approximate any regular function and have a faster training phase than other similar neural networks. However, the activation of each neuron depends on the euclidean distance between a pattern and the neuron center. Therefore, the activation function is symmetrical and all attributes are considered equally relevant. This could be solved by altering the metric used in the activation function (i.e. using non-symmetrical metrics). The Mahalanobis distance is such a metric, that takes into account the variability of the attributes and their correlations. However, this distance is computed directly from the variance-covariance matrix and does not consider the accuracy of the learning algorithm. In this paper, we propose to use a generalized euclidean metric, following the Mahalanobis structure, but evolved by a Genetic Algorithm (GA). This GA searches for the distance matrix that minimizes the error produced by a fixed RBNN. Our approach has been tested on two domains and positive results have been observed in both cases

Evolving Generalized Euclidean Distances for Training RBNN

In Radial Basis Neural Networks (RBNN), the activation of each neuron depends on the Euclidean distance between a pattern and the neuron center. Such a symmetrical activation assumes that all attributes are equally relevant, which might not be true. Non-symmetrical distances like Mahalanobis can be used. However, this distance is computed directly from the data covariance matrix and therefore the accuracy of the learning algorithm is not taken into account. In this paper, we propose to use a Genetic Algorithm to search for a generalized Euclidean distance matrix, that minimizes the error produced by a RBNN

Performance evaluation and limitations of a vision system on a reconfigurable/programmable chip

This paper presents a survey of the characteristics of a vision system implemented in a reconfigurable/programmable chip (FPGA). System limitations and performance have been evaluated in order to derive specifications and constraints for further vision system synthesis. The system hereby reported has a conventional architecture. It consists in a central microprocessor (CPU) and the necessary peripheral elements for data acquisition, data storage and communications. It has been designed to stand alone, but a link to the programming and debugging tools running in a digital host (PC) is provided. In order to alleviate the computational load of the central microprocessor, we have designed a visual co-processor in charge of the low-level image processing tasks. It operates autonomously, commanded by the CPU, as another system peripheral. The complete system, without the sensor, has been implemented in a single reconfigurable chip as a SOPC. The incorporation of a dedicated visual co-processor, with specific circuitry for low-level image processing acceleration, enhances the system throughput outperforming conventional processing schemes. However, timemultiplexing of the dedicated hardware remains a limiting factor for the achievable peak computing power. We have quantified this effect and sketched possible solutions, like replication of the specific image processing hardware

Medidas térmicas de alta precisión en el laboratorio geodinámico de Lanzarote

Since 1988, under the exislinq collaboralion belween the Instituto de Astronomía y Geodesia, the Observaloire Royale de Belgique and the European Center for Geodynamics and Seismology,lhermal measuremenls have be en made in the geodynamlc slalion Cueva de los Verdes (Lanzarole, Canary Islands), that have been used lo check the quality oí the sensors used as well the thermal slablllly of the laboralory. Several experiments have been performed:measuremenls oí vertical and horizontal thermal profiles, continuous records of the temperature In different points of rock and continuos record of the ambient temperature of the laboratory. The measures of the temperature profiles have been made in three observation campaings, the results of which we pr:~ent here. We have achieved precisions in the range of 10 oC. We have found a vertical gradient O.03oC/m in the profile temperature. The long and short period variations of rock and ambient temperature have been studied. The results of the harmonic analysis of those temperatures are presented here.Peer reviewe

Diseño y simulación de estructuras de sensores de microondas planares para la detección de presencia de glifosato en el agua

Trabajo de Investigación TecnológicaEl diseño de filtros en configuraciones planares bajo la tecnología de la utilización de resonadores de anillos complementarios divididos y su respectivo modelamiento, permite presentar una información completa sobre el uso de la electrónica de alta frecuencia, la caracterización de sensores planares, su implementación, curvas de comportamiento y descripción de su respuesta al ser expuestos a diferentes concentraciones de glifosato. Estos resultados permitirán el desarrollo de tablas y curvas de comportamiento para ser utilizadas en cualquier fuente de agua, con la manipulación de los prototipos creados en el proyecto.1. TÍTULO 2. ALTERNATIVA 3. LÍNEA DE INVESTIGACIÓN 4. EJE TEMÁTICO. 5. INTRODUCCIÓN 6. ANTECEDENTES Y JUSTIFICACIÓN 7. PLANTEAMIENTO DEL PROBLEMA 8. MARCO CONCEPTUAL 9. MARCO TEÓRICO 10. ESTADO DEL ARTE 11. OBJETIVOS 12. ALCANCES Y LIMITACIONES 13. METODOLOGIA 14. CSRR Y SIMULACION EN ADS 15. PROCEDIMIENTO EXPERIMENTAL 16. RESULTADOS Y ANALISIS 17. CONCLUSIONES 18. BIBLIOGRAFÍAPregradoIngeniero Electrónic