86 research outputs found

    Screening of chemicals for human bioaccumulative potential with a physiologically based toxicokinetic model

    Get PDF
    Human bioaccumulative potential is an important element in the risk assessment of chemicals. Due to the high number of synthetic chemicals, there exists the need to develop prioritisation strategies. The purpose of this study was to develop a predictive tool for human bioaccumulation risk assessment that incorporates not only the chemical properties of the compounds, but also the processes that tend to decrease the concentration of the compound such as metabolisation. We used a generic physiologically based toxicokinetic model that based on in vitro human liver metabolism data, minimal renal excretion and a constant exposure was able to assess the bioaccumulative potential of a chemical. The approach has been analysed using literature data on well-known bioaccumulative compounds and liver metabolism data from the ECVAM database and a subset of the ToxCast phase I chemical library—in total 94 compounds covering pharmaceuticals, plant protection products and industrial chemicals. Our results provide further evidence that partitioning properties do not allow for a reliable screening criteria for human chemical hazard. Our model, based on a 100% intestinal absorption assumption, suggests that metabolic clearance, plasma protein-binding properties and renal excretion are the main factors in determining whether bioaccumulation will occur and its amount. It is essential that in vitro metabolic clearance tests with metabolic competent cell lines as well as plasma protein-binding assays be performed for suspected bioaccumulative compounds

    Multichannel massive audio processing for a generalized crosstalk cancellation and equalization application using GPUs

    Full text link
    [EN] Multichannel acoustic signal processing has undergone major development in recent years due to the increased com- plexity of current audio processing applications, which involves the processing of multiple sources, channels, or filters. A gen- eral scenario that appears in this context is the immersive reproduction of binaural audio without the use of headphones, which requires the use of a crosstalk canceler. However, generalized crosstalk cancellation and equalization (GCCE) requires high com- puting capacity, which is a considerable limitation for real-time applications. This paper discusses the design and implementation of all the processing blocks of a multichannel convolution on a GPU for real-time applications. To this end, a very efficient fil- tering method using specific data structures is proposed, which takes advantage of overlap-save filtering and filter fragmentation. It has been shown that, for a real-time application with 22 inputs and 64 outputs, the system is capable of managing 1408 filters of 2048 coefficients with a latency time less than 6 ms. The proposed GPU implementation can be easily adapted to any acoustic environment, demonstrating the validity of these co-processors for managing intensive multichannel audio applications.This work has been partially funded by Spanish Ministerio de Ciencia e Innovacion TEC2009-13741, Generalitat Valenciana PROMETEO 2009/2013 and GV/2010/027, and Universitat Politecnica de Valencia through Programa de Apoyo a la Investigacion y Desarrollo (PAID-05-11).Belloch Rodríguez, JA.; Gonzalez, A.; Martínez Zaldívar, FJ.; Vidal Maciá, AM. (2013). Multichannel massive audio processing for a generalized crosstalk cancellation and equalization application using GPUs. Integrated Computer-Aided Engineering. 20(2):169-182. https://doi.org/10.3233/ICA-130422S16918220

    Soft MIMO detection through sphere decoding and box optimization

    Full text link
    [EN] Achieving optimal detection performance with low complexity is one of the major challenges, mainly in multiple-input multiple-output (MIMO) detection. This paper presents three low-complexity Soft-Output MIMO detection algorithms that are based mainly on Box Optimization (BO) techniques. The proposed methods provide good performance with low computational cost using continuous constrained optimization techniques. The rst proposed algorithm is a non-optimal Soft-Output detector of reduced complexity. This algorithm has been compared with the Soft-Output Fixed Complexity (SFSD) algorithm, obtaining lower complexity and similar performance. The two remaining algorithms are employed in a turbo receiver, achieving the max-log Maximum a Posteriori (MAP) performance. The two Soft-Input Soft-Output (SISO) algorithms were proposed in a previous work for soft-output MIMO detection. This work presents its extension for iterative decoding. The SISO algorithms presented are developed and compared with the SISO Single Tree Search algorithm (STS), in terms of efficiency and computational cost. The results show that the proposed algorithms are more efficient for high order constellation than the STS algorithm.Simarro, MA.; García Mollá, VM.; Vidal Maciá, AM.; Martínez Zaldívar, FJ.; Gonzalez, A. (2018). Soft MIMO detection through sphere decoding and box optimization. Signal Processing. 145:48-58. https://doi.org/10.1016/j.sigpro.2017.11.010S485814

    Parallel signal detection for generalized spatial modulation MIMO systems

    Full text link
    [EN] Generalized Spatial Modulation is a recently developed technique that is designed to enhance the efficiency of transmissions in MIMO Systems. However, the procedure for correctly retrieving the sent signal at the receiving end is quite demanding. Specifically, the computation of the maximum likelihood solution is computationally very expensive. In this paper, we propose a parallel method for the computation of the maximum likelihood solution using the parallel computing library OpenMP. The proposed parallel algorithm computes the maximum likelihood solution faster than the sequential version, and substantially reduces the worst-case computing times.This work has been partially supported by the Spanish Ministry of Science, Innovation and Universities and by the European Union through grant RTI2018- 098085-BC41 (MCUI/AEI/FEDER), by GVA through PROMETEO/2019/109, and by RED 2018-102668-T. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.García Mollá, VM.; Simarro, MA.; Martínez Zaldívar, FJ.; Boratto, M.; Alonso-Jordá, P.; Gonzalez, A. (2022). Parallel signal detection for generalized spatial modulation MIMO systems. The Journal of Supercomputing. 78(5):7059-7077. https://doi.org/10.1007/s11227-021-04163-y7059707778

    Intervención educativa dirigida a la promoción de salud bucal en el adulto mayor

    Get PDF
    Introducción: actualmente el acelerado envejecimiento poblacional constituye una preocupación para diferentes países, entre los que se encuentra Cuba. La realización de actividades de promoción de salud bucal orientada a los adultos mayores posibilita la mejora continua en el bienestar general de este grupo poblacional.Objetivo: evaluar la efectividad de una intervención educativa dirigida a la promoción de salud bucal en el Adulto Mayor.Material y Métodos: se realizó un estudio no observacional cuasi-experimental de antes-después sin grupo control en el período de diciembre 2017- abril 2018 en los adultos mayores de la “Casa de abuelos” de Banes. Sexo, nivel de información sobre el cuidado de la salud bucal, hábitos nocivos y efectividad del programa educativo, constituyeron las variables del estudio. A partir de la información obtenida, se diseñó y aplicó el programa educativo “Sonreír con experiencia”.Resultados: antes de la intervención, los participantes no mantenían conductas adecuadas para el cuidado de la salud bucal y tenían escasos conocimientos sobre los factores de riesgo del cáncer bucal. El programa ofrece acciones para fomentar el cuidado del aparato estomatognático, información sobre los efectos dañinos de los hábitos que predisponen a contraer afecciones bucales, la realización del autoexamen, todo concebido para los ancianos y su familia, lográndose que adquirieran conocimientos con respecto al cuidado y prevención de enfermedades bucales y se convirtieran en promotores en sus hogares.Conclusiones: la intervención educativa permitió elevar el nivel de información y las prácticas encaminadas a prevenir la aparición de enfermedades bucales en este grupo poblacional

    Parallel Implementation Strategies for MIMO ID-BICM Systems

    Full text link
    [EN] One of the current techniques proposed for multiple transmit and receive antennas wireless communication systems is the use of error control coding and iterative detection and decoding at the receiver. These sophisticated techniques produce a significant increase of the computational cost and require large computational power. The use of modern computer facilities as multicore and multi-GPU (Graphics Processing Unit) processors can decrease the computational time required, representing a promising solution for the receiver implementation in these systems. In this paper we explain how iterative receivers can improve the performance of suboptimal detectors. We also introduce a novel parallel receiver scheme based on a hybrid computing model where CPUs and GPUs work together to accelerate the detection and decoding steps; this design comes to exploit the features of the GPU NVIDIA Kepler architecture respect to the previous one in order to optimize the communication system performance.This work has been partially funded by PROMETEO/2009/013 project of Generalitat Valenciana, projects TEC2009-13741 of the Ministerio Español de Ciencia e Innovación, TEC2012-38142-C04 of the Ministerio Español de Economía y Competitividad, and PAID-05-2011 of Universitat Politècnica de València.Simarro Haro, MDLA.; Ramiro Sánchez, C.; Martínez Zaldívar, FJ.; Vidal Maciá, AM.; González Téllez, A.; Piñero Sipán, MG.; García Mollá, VM. (2013). Parallel Implementation Strategies for MIMO ID-BICM Systems. Waves. 5-13. http://hdl.handle.net/10251/57906S51

    The Role of Faults as Barriers in Confined Seismic Sequences: 2021 Seismicity in the Granada Basin (Betic Cordillera)

    Get PDF
    Fault barriers are key structures for studying seismic hazard in regions of intense brittle deformation. The interaction between fault sets affects their seismogenic behavior, if some of them act as barriers. The Granada Basin, in the Betic Cordillera, is a region affected by shallow brittle deformation, as it was the scenario for the recent Granada 2021 seismic sequence. This seismicity presented a swarm behavior at the beginning of the sequence, followed by mainshock-aftershock features. Geological and gravity data presented here reveal that the basement is affected by two sets of NW-SE and NE-SW normal faults and intensely deformed by vertical NW-SE joints. Improved relocation of the Granada 2021 seismicity reveals a confined chimney-shape seismicity caused by the activity of a 2 km long NW-SE normal fault segment. The confinement of the sequence is associated with the NE-SW fault set acting as a barrier that restricts the rupture area, limiting the maximum magnitude, and favoring the recurrence of events with smaller magnitude. The chimney-shape of the seismic sequence suggests that the deformation is propagated vertically to the surface, facilitated by preexisting fractures. The shallow extensional deformation during the uplift of the central Betic Cordillera drove the activity of the local structures obliquely to the regional extensional trends, as evidenced by the seismic sequence. This multidisciplinary study improves the knowledge on the origin of the Granada Basin and underlies the important role of preexisting fractures on fault segmentation and seismic propagation, decreasing the seismic potential of this area.Spanish projects Evaluación de la Peligrosidad de Inestabilidades de Laderas Asociadas a Terremotos (CGL2015-65602-R AEI-FEDER)B-RNM-301-UGR18 (Junta de Andalucía/FEDER);P18-RT-3275 (Junta de Andalucía/FEDER)Programa Operativo FEDER Andalucía 2014–2020 – call made by the University of Jaén (Ref. 126344)POAIUJA 2021/2022 from the University of JaénAndalusian research groups RNM-148Andalusian research groups RNM-282Andalusian research groups RNM-37

    A Model-Based Prioritisation Exercise for the European Water Framework Directive

    Get PDF
    A model-based prioritisation exercise has been carried out for the Water Framework Directive (WFD) implementation. The approach considers two aspects: the hazard of a certain chemical and its exposure levels, and focuses on aquatic ecosystems, but also takes into account hazards due to secondary poisoning, bioaccumulation through the food chain and potential human health effects. A list provided by EU Member States, Stakeholders and Non-Governmental Organizations comprising 2,034 substances was evaluated according to hazard and exposure criteria. Then 78 substances classified as “of high concern” where analysed and ranked in terms of risk ratio (Predicted Environmental Concentration/Predicted No-Effect Concentration). This exercise has been complemented by a monitoring-based prioritization exercise using data provided by Member States. The proposed approach constitutes the first step in setting the basis for an open modular screening tool that could be used for the next prioritization exercises foreseen by the WFD

    Joint effects of nutrients and contaminants on the dynamics of a food chain in marine ecosystems

    Get PDF
    We analyze the joint effect of contaminants and nutrient loading on population dynamics of marine food chains by means of bifurcation analysis. Contaminant toxicity is assumed to alter mortality of some species with a sigmoidal dose-response relationship. A generic effect of pollutants is to delay transitions to complex dynamical states towards higher nutrient load values, but more counterintuitive consequences arising from indirect effects are described. In particular, the top predator seems to be the species more affected by pollutants, even when contaminant is toxic only to lower trophic levels

    The impact of GPU/Multicore in Signal Processing: a quantitative approach

    Get PDF
    [EN] This paper presents a meaningful practical performance comparison between the last generation of Graphics Processing Units (GPUs) and the last generation multi-core CPUs when they are used to solve given Signal Processing algorithms. Two kinds of tests were considered: when GPU pre-designed computational libraries were available, and when the GPU code was developed by the authors. Results show that GPUs offer great possibilities, but its programming is still hard and high performances can be obtained only if the algorithm can be adapted to the GPU programming model.This work was financially supported by the Spanish Ministerio de Ciencia e Innovación (Projects TIN2008-06570-C04-02, TEC2009-13741 and CAPAP-H3 TIN2010-12011-E), Universitat Politècnica de València through “Programa de Apoyo a la Investigación y Desarrollo (PAID-05-10)” and Generalitat Valenciana through project PROMETEO/2009/013.García Mollá, VM.; Gonzalez, A.; González García, CY.; Martínez Zaldívar, FJ.; Ramiro Sánchez, C.; Roger Varea, S.; Vidal Maciá, AM. (2011). The impact of GPU/Multicore in Signal Processing: a quantitative approach. Waves. (3):96-106. http://hdl.handle.net/10251/47425S96106
    corecore