314 research outputs found

    A comparative analysis of configurations of linear Fresnel collectors for concentrating solar power

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    Linear Fresnel collector arrays present some relevant advantages in the domain of concentrating solar power because of their simplicity, robustness and low capital cost. However, they also present important drawbacks and limitations, notably their average concentration ratio, which seems to limit significantly the performance of these systems. First, the paper addresses the problem of characterizing the mirror field configuration assuming hourly data of a typical year, in reference to a configuration similar to that of Fresdemo. For a proper comparative study, it is necessary to define a comparison criterion. In that sense, a new variable is defined, the useful energy efficiency, which only accounts for the radiation that impinges on the receiver with intensities above a reference value. As a second step, a comparative study between central linear Fresnel reflectors and compact linear Fresnel reflectors is carried out. This analysis shows that compact linear Fresnel reflectors minimize blocking and shading losses compared to a central configuration. However this minimization is not enough to overcome other negative effects of the compact Fresnel collectors, as the greater dispersion of the rays reaching the receiver, caused by the fact that mirrors must be located farther from the receiver, which yields to lower efficiencies

    Analysis of Ascorbate Peroxidase Genes Expressed in Resistant and Susceptible Wheat Lines Infected by Heterodera avenae.

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    Changes in ascorbate peroxidase (APX) enzyme activity in response to nematode (Heterodera avenae) attack were studied in roots of three hexaploid wheat lines carrying Cre2, Cre5, or Cre7 nematode resistance genes and the susceptible Triticum aestivum cv. Anza. A spectrophotometric analysis was carried out with root extracts of infected plants 4, 7, 11, and 14 days after nematode inoculation using uninfected plant as control. APX induction in infected resistant genotypes was similar and higher than in the susceptible control. The introgression wheat/Aegilops ventricosa H-93-8 line, carrying the Cre2 gene, and its parental line H-10-15 as susceptible control were used to analyze whether this increase of activity was correlated with the induction of APX gene expression. Genes encoding cytosolic forms of APX were induced in roots of both lines in response to nematode infection. This induction took place both earlier and with greater intensity in the resistant line than in the susceptible one, and it was also higher in the root area at the site of nematode attachment

    Spatio-temporal variation of planktonic decapods along the leeward coast of the Fernando de Noronha archipelago, Brazil

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    Ambientes insulares tropicais são considerados verdadeiros hostspots devido a sua alta diversidade, endemismo e importância ecológica. Contudo, ainda são poucos os trabalhos que abordam a composição e ecologia de decápodes planctônicos nesses ambientes. Para determinar a composição, abundância e distribuição espaço-temporal dos decápodes planctônicos, as amostras de zooplâncton foram coletadas por meio de arrastos subsuperficiais em rede cônico-cilíndrica com 300 µm de abertura de malha. A amostragem foi realizada em cinco estações na área costeira a sotavento do Arquipélago de Fernando de Noronha, em julho e dezembro de 2013 e junho e novembro de 2014. Foram registrados 22 táxons de Decapoda, dos quais Brachyura (zoea); Clibanarius sp.; Caridea e Callianassidae foram os grupos mais abundantes. Foram observadas tendências de distribuição anual e temporal para as larvas de Clibanarius sp. e Callianassidae, respectivamente. Alguns táxons apresentaram diferenças entres as estações de amostragem. De forma geral, as maiores densidades larvais foram observadas nas estações ao sul da ilha (Baía dos Golfinhos e Cacimba do Padre) em relação aos menores valores registrados para a estação mais ao norte (Porto de Santo Antônio), indicando a existência de uma possível retenção larval à jusante, na zona costeira interna desse ecossistema insular oceânico.Tropical island environments are considered hotspots due to their high diversity, endemism and ecological importance. However, reports that discuss the composition and ecology of planktonic decapods in these environments are still very few. In order to ascertain the composition, abundance and spatial-temporal distribution of planktonic decapods, zooplankton samples were taken by means of sub-surface hauls with a standard plankton net of 300 µm mesh size. Sampling was carried out at five stations in the nearshore leeward area of the Fernando de Noronha archipelago, in July and December 2013 and June and November 2014. A total of 22 decapod taxa were recorded, among which the most abundant were Brachyura (zoeae), Clibanarius sp., Caridea and Callianassidae. Characteristic annual distribution and temporal tendencies were observed for the larvae of the hermit crab Clibanarius sp. and for the larvae of burrowing shrimps (Callianassidae). Some taxa showed differences between sampling stations. In general, higher abundances were observed in the southern (downstream) stations of the island (Baía dos Golfinhos and Cacimba do Padre), and lower abundances in the northernmost (upstream) station (Porto de Santo Antônio), indicating the existence of larval retention in the nearshore coastal zone of this oceanic island ecosystem

    Ciudades virtuales, educativas e igualitarias: las tecnologías de la información y la comunicación (TIC) y los niños con trastorno del espectro autista (TEA)

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    Cuando un niño es diagnosticado con el Trastorno del Espectro Autista (TEA), diversos especialistas comienzan a trabajar, en busca de terapias que favorezcan su desarrollo integral y su calidad social. Este estudio pretende establecer qué objetivos persiguen los profesionales en las terapias y conocer qué relación tienen con las TIC en su labor profesional. Han participado 49 especialistas, con una experiencia que va desde menos 5 años hasta más de 15, y con una formación inicial que varía entre 9 titulaciones (Psicólogos, Maestros,…). Los resultados muestran que el principal objetivo en las terapias es que los niños sean cada vez más autónomos en sus actividades cotidianas y que logren integrarse y realizar actividades con sus iguales. Y revelan que internet es el segundo medio más utilizado para ampliar su conocimiento sobre el TEA y para buscar actividades y metodologías que ayuden al desarrollo del menor; y que el 57% utiliza la Tablet 2-3 veces por semana en sus intervenciones. Se concluye que si bien el uso de las TIC resulta un recurso útil para los niños con TEA, los especialistas no las utilizan en la misma medida y no se muestran seguros con el uso continuado de las mismas

    Injecting domain knowledge in multi-objective optimization problems: A semantic approach

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    In the field of complex problem optimization with me-taheuristics, semantics has been used for modeling different aspects, such as: problem characterization, parameters, decision-maker's preferences, or algorithms. However, there is a lack of approaches where ontologies are ap-plied in a direct way into the optimization process, with the aim of enhancing it by allowing the systematic incorporation of additional domain knowledge. This is due to the high level of abstraction of ontologies, which makes them difficult to be mapped into the code implementing the problems and/or the specific operators of metaheuristics. In this paper, we present a strategy to inject domain knowledge (by reusing existing ontologies or creating a new one) into a problem implementation that will be optimized using a metaheu-ristic. Thus, this approach based on accepted ontologies enables building and exploiting complex computing systems in optimization problems. We describe a methodology to automatically induce user choices (taken from the ontology) into the problem implementations provided by the jMetal op-timization framework. With the aim of illustrating our proposal, we focus on the urban domain. Concretely, We start from defining an ontology repre-senting the domain semantics for a city (e.g., building, bridges, point of inte-rest, routes, etc.) that allows defining a-priori preferences by a decision ma-ker in a standard, reusable, and formal (logic-based) way. We validate our proposal with several instances of two use cases, consisting in bi-objective formulations of the Traveling Salesman Problem (TSP) and the Radio Net-work Design problem (RND), both in the context of an urban scenario. The results of the experiments conducted show how the semantic specification of domain constraints are effectively mapped into feasible solutions of the tackled TSP and RND scenarios. TUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Phytoplankton biomass dynamics and environmental variables around the Rocas Atoll Biological Reserve, South Atlantic

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    The Rocas Atoll Biological Reserve is located in the Atlantic Ocean, at 3º 51' S and 33º 49' W. It lies 143 nautical miles from the City of Natal, Rio Grande do Norte (Brazil). The purpose of this study was to analyze the hydrology, water masses, currents and chlorophyll a content to determine the dynamics of phytoplankton biomass around the Rocas Atoll. Samples were collected in July 2010 in the area around the Atoll, using the Research Vessel Cruzeiro do Sul of the Brazilian Navy. Two transects were established according to the surface currents, one of which at the southeast of the Atoll (SE) and the other at norwest (NW). Three collection points were determined on each of these transects. Samples were collected at different depths (surface and DCM - Deep Chlorophyll Maximum) and different times (day and night). According to PCA (Principal Component Analysis), the nutrients analyzed, DIN (dissolved inorganic nitrogen), DIP (dissolved inorganic phosphorus) and silicate, were inversely correlated with temperature and dissolved oxygen. Most environmental variables showed a significant increase due to the turbulence on the Northwest transect. There was an increase in the concentration of chlorophyll a and nutrients when the temperature and oxygen in the mixed layer was reduced due to the influence of the SACW (South Atlantic Central Water). Despite the increase observed in some variables such as nutrient salts and chlorophyll a, the temperature in the mixed layer attained a mean value of 23.23 ºC due to the predominance of Tropical Water. The increase of the phytoplankton biomass on the NW transect was, therefore, caused by the "island effect" and not by upwelling.A Reserva Biológica do Atol das Rocas situa-se no Oceano Atlântico, a 3º 51 'S e 33º 49' W, distante 143 milhas náuticas da cidade de Natal, estado do Rio Grande do Norte (Brasil). Este estudo teve como objetivo analisar a hidrologia, massas de água, correntes e o teor de clorofila a para determinar a dinâmica da biomassa fitoplanctônica em torno do Atol das Rocas. As amostras foram coletadas em julho de 2010 na área em torno do atol, usando o navio Oceanográfico da Marinha do Brasil, Cruzeiro do Sul. Dois transectos foram estabelecidos de acordo com a corrente superficial, um transecto em direção sudeste (SE) e o outro, em direção noroeste (NO) do Atol das Rocas. Nestes transectos foram determinados três pontos de coleta para cada um. As amostras foram coletadas em diferentes profundidades (superfície e PMC - Profundidade Máxima de Clorofila) e diferentes períodos do dia (dia e noite). De acordo com a ACP (Análise de Componentes Principais), observou-se que os nutrientes analisados, NID (nitrogênio inorgânico dissolvido), PID (fósforo inorgânico dissolvido) e silicato, correlacionaram-se inversamente com a temperatura e oxigênio dissolvido. A maioria das variáveis ambientais apresentou aumento significativo em função da turbulência no transecto noroeste. Pode-se observar que houve aumento dos teores de clorofila a e nutrientes, e redução da temperatura e oxigênio na camada de mistura em função da influência da ACAS (Água Central do Atlântico Sul). Apesar do aumento observado em algumas variáveis, como sais nutrientes e clorofila a, a temperatura na camada de mistura esteve com valor médio de 23,23 ºC, devido ao predomínio da Água Tropical. Portanto, o aumento de biomassa fitoplanctônica no transecto NW foi provocado pelo "efeito ilha" e não pela ressurgência

    Coordinación de casos prácticos en asignaturas del área de conocimiento “Gestión de la Información” según modelo curricular de informática de la ACM/IEEE 2013

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    Este artículo presenta el estado de desarrollo y resultados preliminares del proyecto de innovación docente de la Universidad de Málaga (PIE15-183): Coor-dinación de casos prácticos en asignaturas del área de conocimiento “Gestión de la Información” según modelo curricular de informática de la ACM/IEEE 2013.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Advances and Pitfalls of Specialized Pain Care through Public and Private Health Care Providers in Catalonia and the Balearic Islands: A Physician’s Survey

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    Optimal diagnosis and treatment of pain require a multidisciplinary approach that demands considerable coordination and forethought. A cross-sectional physician survey based on an online questionnaire was carried out to assess the adoption of multidisciplinary working patterns, compare the public and private models, and provide an update on the resources and organization of specialized pain care in Catalonia and the Balearic Islands. Active pain practitioners identified through the Catalan Health Service and Pain Society databases were sent an invitation in December 2020. Of the 321 physicians contacted, 91 (28.3%) answered and 71 provided complete responses (commonly anesthesiologists, representing 92 different sites; some worked at public and private sites). Up to 78.7% reported working in pain management teams, but only 53.5% were regularly involved in teaching or research activities. Thus, the proportion of multidisciplinary sites lies somewhere in-between. Median wait times were significantly shorter and within the recommended standards in private practices (e.g., 15 vs. 90 days in public practices for noncancer patients). In turn, private practices were slightly less staffed and equipped, albeit the differences did not reach statistical significance. Respondents made a median of 530 regular and 30 emergency visits per year, of which 190 involved interventional procedures. They offered a wide range of pharmacological and interventional therapies, although psychotherapy and the most sophisticated procedures were only available in <= 50% of sites. Pain clinicians and facilities are reasonably available in Catalonia, but barely more than half are truly multidisciplinary. Public and private practices differ in some aspects; the latter seems to be more accessible, but it is restricted to patients who can afford it. Compared to previous reports, this update shows both advances and outstanding issues. Multidisciplinary care could be expanded by incorporating more psychologists and some interventional procedures. The public practices should reduce wait times

    TITAN: A knowledge-based platform for Big Data workflow management

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    Modern applications of Big Data are transcending from being scalable solutions of data processing and analysis, to now provide advanced functionalities with the ability to exploit and understand the underpinning knowledge. This change is promoting the development of tools in the intersection of data processing, data analysis, knowledge extraction and management. In this paper, we propose TITAN, a software platform for managing all the life cycle of science workflows from deployment to execution in the context of Big Data applications. This platform is characterised by a design and operation mode driven by semantics at different levels: data sources, problem domain and workflow components. The proposed platform is developed upon an ontological framework of meta-data consistently managing processes and models and taking advantage of domain knowledge. TITAN comprises a well-grounded stack of Big Data technologies including Apache Kafka for inter-component communication, Apache Avro for data serialisation and Apache Spark for data analytics. A series of use cases are conducted for validation, which comprises workflow composition and semantic meta-data management in academic and real-world fields of human activity recognition and land use monitoring from satellite images.Universidad de Málaga. Andalucía TECH

    Secretion of biologically active interferon-gamma inducible protein-10 (IP-10) by Lactococcus lactis

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    <p>Abstract</p> <p>Background</p> <p>Chemokines are a large group of chemotactic cytokines that regulate and direct migration of leukocytes, activate inflammatory responses, and are involved in many other functions including regulation of tumor development. Interferon-gamma inducible-protein-10 (IP-10) is a member of the C-X-C subfamily of the chemokine family of cytokines. IP-10 specifically chemoattracts activated T lymphocytes, monocytes, and NK cells. IP-10 has been described also as a modulator of other antitumor cytokines. These properties make IP-10 a novel therapeutic molecule for the treatment of chronic and infectious diseases. Currently there are no suitable live biological systems to produce and secrete IP-10. <it>Lactococcus lactis </it>has been well-characterized over the years as a safe microorganism to produce heterologous proteins and to be used as a safe, live vaccine to deliver antigens and cytokines of interest. Here we report a recombinant strain of <it>L. lactis </it>genetically modified to produce and secrete biologically active IP-10.</p> <p>Results</p> <p>The IP-10 coding region was isolated from human cDNA and cloned into an <it>L. lactis </it>expression plasmid under the regulation of the pNis promoter. By fusion to the usp45 secretion signal, IP-10 was addressed out of the cell. Western blot analysis demonstrated that recombinant strains of <it>L. lactis </it>secrete IP-10 into the culture medium. Neither degradation nor incomplete forms of IP-10 were detected in the cell or supernatant fractions of <it>L. lactis</it>. In addition, we demonstrated that the NICE (nisin-controlled gene expression) system was able to express IP-10 "de novo" even two hours after nisin removal. This human IP-10 protein secreted by <it>L. lactis </it>was biological active as demonstrated by Chemotaxis assay over human CD3+T lymphocytes.</p> <p>Conclusion</p> <p>Expression and secretion of mature IP-10 was efficiently achieved by <it>L. lactis </it>forming an effective system to produce IP-10. This recombinant IP-10 is biologically active as demonstrated by its ability to chemoattract human CD3+ T lymphocytes. This strain of recombinant <it>L. lactis </it>represents a potentially useful tool to be used as a live vaccine <it>in vivo</it>.</p
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