2,958 research outputs found

    Morphometric and morphological studies of Red seabream (Pagellus bogaraveo) otoliths from the Strait of Gibraltar: Exploratory analysis of its application for ageing

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    In the last years, the otoliths have become a useful tool for the determination of ichthyic species, because these structures present a high morphologic specificity. Besides, its shape should change between the sampled ages. Thus, our study deals with several features of the otoliths (sagitta) related with the age of the individuals. 235 (Morphometry) and 53 (Morphology) otoliths from Red seabream samples, 2003 – 2008, of the Strait of Gibraltar were analyzed. The combined use of both features (morphometrics and morphological) resulted in a discriminant function which an ageing success higher than 70%.Versión del edito

    Breast cancer mortality in Spain: Has it really declined?

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    Objectives: In recent years, the incidence of breast cancer has increased in Spain but mortality has decreased, particularly since 1992. Despite the general decrease in mortality, the intensity of this disease differs between age groups. The main objective of this study was to examine mortality due to breast cancer for different age groups in Spain from 1981 to 2007, and to forecast the mortality rate in 2023. Study design: Ecological study. Methods: Trends in mortality due to breast cancer were analysed using the LeeeCarter model, which is the typical analysis for mortality in the general population but is rarely used to analyse specific causes of death. Results: This study found a decreasing trend in mortality due to breast cancer from 1993 to 2007, and it is predicted that this trend will continue. However, mortality rates varied between age groups: a decreasing trend was seen in younger and middle-aged women, whereas mortality rates remained stable in older women. Conclusions: Preventive breast cancer practices should differ by patient age.Ministerio de Educacion y Ciencia, Spain, Projects MTM2010-14961 and MTM2008-05152.Álvaro Meca, A.; Debón Aucejo, AM.; Gil Prieto, R.; Gil De Miguel, Á. (2012). Breast cancer mortality in Spain: Has it really declined?. Public Health. 126(10):891-895. doi:10.1016/j.puhe.2012.05.031S8918951261

    e-WASTE: Everything an ICT Scientist and Developer Should Know

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    [EN] Every dazzling announcement of a new smart phone or trendy digital device is the prelude to more tons of electronic waste (e-waste) being produced. This e-waste, or electronic scrap, is often improperly added to common garbage, rather than being separated into suitable containers that facilitate the recovery of toxic materials and valuable metals. We are beginning to become aware of the problems that e-waste can generate to our health and the environment. However, most of us are still not motivated enough to take an active part in reversing the situation. The aim of this article is to contribute to increase this motivation by pointing out the significant problem that e-waste represents and its social and environmental implications. We have chosen this forum in which multidisciplinary researchers in ICT from all countries access on regularly to explain the serious problems we are exposed to when we do not make a responsible and correct use of technology. In this paper, we also survey the composition of contemporary electronic devices and the possibilities and difficulties of recycling the elements they contain. As researchers, our contributions in science enable us to find solutions to current problems and to design more and more powerful intelligent devices. But responsible researchers must be aware of the negative effects that this industry causes us and, consequently, assume their commitment with more sustainable designs and developments. Therefore, the knowledge of e-waste issues is crucial also in the scientific world. Researchers should consider this problem and contribute to minimize it or find new solutions to manage it. These must be the additional challenges in our projects.This work was supported in part by the Spanish Ministry of Economy and Competitiveness under Grant TIN2013-43913-R.Pont Sanjuan, A.; Robles Martínez, A.; Gil, JA. (2019). e-WASTE: Everything an ICT Scientist and Developer Should Know. IEEE Access. 7:169614-169635. https://doi.org/10.1109/ACCESS.2019.2955008S169614169635

    Monitoring E-commerce Adoption from Online Data

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    [EN] The purpose of this paper is to propose an intelligent system to automatically monitor the firms¿ engagement in e-commerce by analyzing online data retrieved from their corporate websites. The design of the proposed system combines web content mining and scraping techniques with learning methods for Big Data. Corporate websites are scraped to extract more than 150 features related to the e-commerce adoption, such as the presence of some keywords or a private area. Then, these features are taken as input by a classification model that includes dimensionality reduction techniques. The system is evaluated with a data set consisting of 426 corporate websites of firms based in France and Spain. The system successfully classified most of the firms into those that adopted e-commerce and those that did not, reaching a classification accuracy of 90.6%. This demonstrates the feasibility of monitoring e-commerce adoption from online data. Moreover, the proposed system represents a cost-effective alternative to surveys as method for collecting e-commerce information from companies, and is capable of providing more frequent information than surveys and avoids the non-response errors. This is the first research work to design and evaluate an intelligent system to automatically detect e-commerce engagement from online data. This proposal opens up the opportunity to monitor e-commerce adoption at a large scale, with highly granular information that otherwise would require every firm to complete a survey. In addition, it makes it possible to track the evolution of this activity in real time, so that governments and institutions could make informed decisions earlier.This work has been partially supported by the Spanish Ministry of Economy and Competitiveness with Grant TIN2013-43913-R, and by the Spanish Ministry of Education with Grant FPU14/02386.Blazquez, D.; Domenech, J.; Gil, JA.; Pont Sanjuan, A. (2018). 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    A Melissopalynological map of the south and southwest of the Buenos Aires province, Argentina

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    El objetivo de este trabajo fue elaborar un mapa melitopalinológico del sur y sudoeste de la provincia de Buenos Aires, Argentina, con datos de análisis polínicos de 127 muestras de miel provenientes de las eco-regiones Pampa, Distrito del Caldén en el Espinal, y Monte de Llanuras y Mesetas, recolectadas en el período 1992-2002. Utilizando análisis de componentes principales y de cluster, los partidos se agruparon en cinco regiones: I (Tres Arroyos, San Cayetano, Coronel Pringles y Coronel Dorrego), II (Guaminí, Saavedra, Coronel Suárez y Adolfo Alsina), III (Coronel Rosales, Monte Hermoso, Bahía Blanca y Villarino), IV (Patagones y Tornquist) y V (Puán). En las Regiones I, III y IV el 80% de las muestras fueron monoflorales. La Región I se caracterizó por la presencia de un 50% de mieles de Helianthus annuus y de un 10% de mieles de trébol; la Región III por 60% de mieles de Eucalyptus sp.; y la Región IV por 30% de mieles de Diplotaxis tenuifolia. En las Regiones II y V el 50% de las mieles fueron monoflorales: la Región II se distinguió por la presencia de 50% de mieles de H. annuus y la Región V por 15% de mieles de Larrea divaricata y 15% de mieles de Vicia sp. Las mieles multiflorales de la Región V se destacaron por la presencia de pólen de Condalia microphylla. La mayor diversidad de tipos polínicos correspondió a las familias Fabaceae y Asteraceae. La asociación de Eucalyptus sp., Centaurea sp. y Diplotaxis tenuifolia caracterizó a las mieles de las cinco regiones. La variabilidad natural de las muestras de miel hace muy difícil definir límites precisos entre las diferentes regiones.The aim of this work was to produce a melissopalynological map of the south and southwest of the Buenos Aires Province, Argentina, using pollen analysis data pertaining to 127 honey samples from the Pampa, Espinal (the Calden District), and Monte de Llanuras y Mesetas ecoregions, collected over the period 1992-2002. Using principal components and hierarchical cluster analysis, the different districts were grouped into five regions: I (Tres Arroyos, San Cayetano, Coronel Pringles and Coronel Dorrego), II (Guaminí, Saavedra, Coronel Suárez and Adolfo Alsina), III (Coronel Rosales, Monte Hermoso, Bahía Blanca and Villarino), IV (Patagones and Tornquist), and V (Puán). In Regions I, III and IV, 80% of honey samples were monofloral: Region I was characterized by the presence of 50% Helianthus annuus honeys and 10% clover honeys, Region III by 65% Eucalyptus sp. honeys, and Region IV by 30% Diplotaxis tenuifolia honeys. In Regions II and V, 50% of honeys were monofloral. Region II was distinguished by the presence of 50% H. annuus honeys, and Region V by 15% Larrea divaricata and 15% Vicia sp. honeys. The multifloral honeys of Region V included samples containing Condalia microphylla pollen. The families Fabaceae and Asteraceae provided the greatest diversity of pollen types. The association of Eucalyptus sp., Centaurea sp., and Diplotaxis tenuifolia characterised the honeys from all five regions. The natural variability of honey samples renders it very difficult to define the boundaries between the different regions

    Characterization of honeys from west and south Buenos Aires province, Argentina

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    Pollen analyses were carried out on 33 honey samples from Espinal, Monte de Llanuras y Mesetas and Pampeana phytogeographical Provinces, collected during the 2000-2001 period. Sample processing as well as qualitative and quantitative analyses were performed according to standard techniques. Sixty-seven morphological pollen types were identified. The association of Eucalyptus sp. (E. camaldulensis Dehnh., E. viminalis Labill.), Centaurea sp. (C. solstitialis L., C. calcitrapa L.) and Diplotaxis tenuifolia DC. characterized these honeys. Twelve samples were unifloral: six from Eucalyptus sp., five from Helianthus annuus L., and one from Brassicaceae. Asteraceae and Fabaceae were the most representative botanical families

    A methodology for economic evaluation of cloud-based web applications

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    [EN] Cloud technology is an attractive infrastructure solution to optimize the scalability and performance of web applications. The workload of these applications typically fluctuates between peak and valley loads and sometimes in an unpredictable way. Cloud systems can easily deal with this fluctuation because they provide customers with an almost unlimited on-demand infrastructure capacity using a pay-per-use model, which enables internet-based companies to pay for the actual consumption instead of peak capacity. In this paradigm, this paper links the business model of an internet-based company to the performance evaluation of the infrastructure. To this end, the paper develops a new methodology for assessing the costs and benefits of implementing web-based applications in the cloud. Traditional performance models and indexes related to usage of the main system resources (such as processor, memory, storage, and bandwidth) have been reformulated to include new metrics (such as customer losses and service costs) that are useful for business managers. Additionally, the proposed methodology has been illustrated with a case study of a typical e-commerce scenario. Experimental results show that the proposed metrics enable internet-based companies to estimate the cost of adopting a particular cloud configuration more accurately in terms of the infrastructure cost and the cost of losing customers due to performance degradation. Consequently, the methodology can be a useful tool to assess the feasibility of business plans.This work has been partially supported by the Spanish Ministry of Economy and Competitiveness under Grant TIN2013-43913-R.Domenech, J.; Peña Ortiz, R.; Gil, JA.; Pont Sanjuan, A. (2016). A methodology for economic evaluation of cloud-based web applications. International Journal of Information Technology and Decision Making. 15(6):1555-1578. https://doi.org/10.1142/S021962201650036XS1555157815

    Automatic detection of e-commerce availability from web data

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    Resumen de la ponencia[EN] In the transition to the digital economy, the implementation of e-commerce strategies contributes to foster economic growth and obtain competitive advantages. Indeed, national and supranational statistics offices monitor the adoption of e-commerce solutions by conducting periodic surveys to businesses. However, the information about e-commerce adoption is often available online in each company corporate website, which is usually public and suitable for being automatically retrieved and processed.In this context, this work proposes and develops an intelligent system for automatically detecting and monitoring e-commerce availability by analyzing data retrieved from corporate websites. This system combines web scraping techniques with some learning methods for Big Data, and has been evaluated with a data set consisting of 426 corporate websites of manufacturing firms based in France and Spain.Results show that the proposed model reaches a classification precision of about 85% in the test set. A more detailed analysis evidences that websites with e-commerce tend to include some specific keywords and have a private area. Our proposal opens up the opportunity to monitor e-commerce adoption at a large scale, with highly granular information that otherwise would have required every firm to complete a survey.Blázquez Soriano, MD.; Domenech, J.; Gil, JA.; Pont Sanjuan, A. (2016). Automatic detection of e-commerce availability from web data. En CARMA 2016: 1st International Conference on Advanced Research Methods in Analytics. Editorial Universitat Politècnica de València. 121-121. https://doi.org/10.4995/CARMA2016.2016.3603OCS12112

    Oil extraction and crude oil price behavior in the United States: a fractional integration and cointegration analysis.

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    This study reviews the relationship between the different types of oil extraction such as horizontal drilling or fracking, or directional drilling, which is a hybrid between vertical and horizontal, on the behavior of West Texas Intermediate crude oil prices. In doing so the study adds a new dimension to the literature on the relationship between oil price and extraction techniques. The analysis is based on statistical properties using the VAR model of Fractional Cointegration, reflecting evidence of cointegration between the series, and indicating a long-term equilibrium relationship. In addition, we apply the wavelet transform to analyze the structural changes in the price of West Texas Intermediate brought about by changes in drilling technology. Our results show that all three forms of extraction and West Texas Intermediate prices reach high levels of correlation, particularly around 2014. We conclude that a decrease in production based on any form of crude oil extraction leads to an increase in the price of crude oil.pre-print1097 K
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