1,179 research outputs found

    Endogenous longevity, biological deterioration and economic growth

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    The identification of the types of bidirectional interactions that take place between longevity and economic growth in the long-run is carried out by means of the integration of human capital accumulation, innovation in medical technology, a health goods sector, and individual decisions on health and longevity in a dynamic general equilibrium set-up. In this context, in which individual agents decide not only on their “quality” of life but also on its “quantity”, the mere process of biological deterioration, that is to say, the continuous loss of health goods effectiveness in maintaining a given level of health as individuals age, provides the reason for an additional, and new, engine of growth.Biological deterioration; Health; Health goods; Endogenous longevity; Endogenous growth

    La deterioración de las piedras de la Catedral de Oviedo. 2° Parte: Formas y Fenómenos de Alteración

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    The different forms of superficial alteration that appear on the stones of the Oviedo Cathedral are described and localed, in this part of the paper. The more common phenomena of deterioration of the monument are also defined, stressing on the crusts.En esta parte del trabajo, se describen y localizan las diversas formas de alteración superficial observadas sobre las piedras de la Catedral. Asimismo se concretan los fenómenos de deterioración más generalizados en el monumento, haciendo especial énfasis en el análisis de las costras

    Estudios experimentales sobre la consolidación y protección de los materiales calcáreos de la Catedral de Oviedo. 1.ª parte

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    The suitability of some consolidating and protecting products, to be applied to the deteriorated calcareous stones of the Cathedral of Oviedo, is presented. A proposed procedure and methodology for evaluating that suitability is also described. The studied stones, limestones and dolomites, have been experimentally subjected in laboratory to some treatment products: ethyl silicate, oligomeric silane and silicon resin. Some physical properties of those stones were evaluated before and after the treatments with the mentioned products. Those properties (porosity, water absorption, compressive strength and deformability, mechanical microfissuration threshold, acoustic emission, etc.) were selected according to the significative role they play on the process of stone alteration or in supporting the proposed conclusions.Se presenta una metodología de trabajo encaminada a evaluar la idoneidad de ciertos productos consolidantes y protectores aplicados a piedras monumentales deterioradas. Para ello, en esta 1.ª parte, se determinan una serie de propiedades físicas, antes y después de aplicar los tratamientos. Dichas propiedades han sido seleccionadas por su incidencia en los mecanismos de alteración. Las piedras ensayadas proceden de la Catedral de Oviedo, son rocas calcáreas: calizas y dolomías. Los productos de tratamiento empleados han sido: silicato de etilo, silano oligomérico y resina silicónica. Se concluye con la comparación de las variaciones en las propiedades determinadas, antes y después del tratamiento, según el producto empleado

    STENOSTOMUM LEUCOPS DUGÈS, 1828 (PLATYHELMINTHES, CATENULIDA): A PUTATIVE SPECIES COMPLEX WITH PHENOTYPIC PLASTICITY

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    RESUMO Stenostomum são pequenos vermes que vivem em água doce e normalmente se reproduzem assexualmente por paratomia. Eles estão na base da filogenia dos platelmintes. Por mais de um século, espécies desse gênero, especialmente S. leucops, vêm sendo empregadas em estudos biológicos, principalmente sobre regeneração. Entretanto, alguns aspectos básicos da biologia destes vermes são ainda pobremente conhecidos. Neste estudo, caracterizamos uma linhagem que vem sendo mantida no laboratório por cinco anos. O tempo necessário para reprodução assexuada e completa formação de zoóides, a 28°C, é de aproximadamente 42,5 horas. O número de células nos zoóides, logo após a paratomia, é de aproximadamente 2.500. O número de zoóides presentes nos vermes é uma característica variável e depende das condições de cultivo. Em alguns procedimentos de cultivo de S. leucops, apenas cadeias com dois zoóides são formadas. No entanto, em outras condições de cultivo, cadeias de até cinco zoóides podem ser observadas. Análise filogenética empregando sequência do gene de Citocromo C Oxidase (COI) mostrou que S. leucops e S. grande constituem um complexo de espécies cujas linhagens mostram altas divergências intraespecíficas.ABSTRACT Species of Stenostomum are small flatworms that live in freshwater and normally reproduce asexually by paratomy. They are basal in the phylogeny of Platyhelminthes. For more than a century, species of this genus, especially S. leucops, have been used in regeneration and other biological studies. However, some basic aspects of their biology are poorly known. Here, we characterized a strain of S. leucops that has been maintained in the laboratory for five years and a recent strain of S. grande. The time required for complete formation of zooids of S. leucops by asexual reproduction is approximately 42.5 hours at 28°C. The number of cells in the zooids, soon after paratomy, is approximately 2,500. The number of zooids formed in the chain is a plastic characteristic and is dependent on the conditions for cultivation. In some cultivation conditions of S. leucops, only worms with two zooids are formed. However, in other conditions, worms with up to five zooids are observed. Phylogenetic analyses of a fragment of the Cytochrome C Oxidase I (COI) sequence showed S. leucops and S. grande species constitute a species complex, the lineages of which having high intraspecific divergences

    STENOSTOMUM LEUCOPS DUGÈS, 1828 (PLATYHELMINTHES, CATENULIDA): A PUTATIVE SPECIES COMPLEX WITH PHENOTYPIC PLASTICITY

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    RESUMO Stenostomum são pequenos vermes que vivem em água doce e normalmente se reproduzem assexualmente por paratomia. Eles estão na base da filogenia dos platelmintes. Por mais de um século, espécies desse gênero, especialmente S. leucops, vêm sendo empregadas em estudos biológicos, principalmente sobre regeneração. Entretanto, alguns aspectos básicos da biologia destes vermes são ainda pobremente conhecidos. Neste estudo, caracterizamos uma linhagem que vem sendo mantida no laboratório por cinco anos. O tempo necessário para reprodução assexuada e completa formação de zoóides, a 28°C, é de aproximadamente 42,5 horas. O número de células nos zoóides, logo após a paratomia, é de aproximadamente 2.500. O número de zoóides presentes nos vermes é uma característica variável e depende das condições de cultivo. Em alguns procedimentos de cultivo de S. leucops, apenas cadeias com dois zoóides são formadas. No entanto, em outras condições de cultivo, cadeias de até cinco zoóides podem ser observadas. Análise filogenética empregando sequência do gene de Citocromo C Oxidase (COI) mostrou que S. leucops e S. grande constituem um complexo de espécies cujas linhagens mostram altas divergências intraespecíficas.ABSTRACT Species of Stenostomum are small flatworms that live in freshwater and normally reproduce asexually by paratomy. They are basal in the phylogeny of Platyhelminthes. For more than a century, species of this genus, especially S. leucops, have been used in regeneration and other biological studies. However, some basic aspects of their biology are poorly known. Here, we characterized a strain of S. leucops that has been maintained in the laboratory for five years and a recent strain of S. grande. The time required for complete formation of zooids of S. leucops by asexual reproduction is approximately 42.5 hours at 28°C. The number of cells in the zooids, soon after paratomy, is approximately 2,500. The number of zooids formed in the chain is a plastic characteristic and is dependent on the conditions for cultivation. In some cultivation conditions of S. leucops, only worms with two zooids are formed. However, in other conditions, worms with up to five zooids are observed. Phylogenetic analyses of a fragment of the Cytochrome C Oxidase I (COI) sequence showed S. leucops and S. grande species constitute a species complex, the lineages of which having high intraspecific divergences

    Adaptive ECMS based on speed forecasting for the control of a heavy-duty fuel cell vehicle for real-world driving

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    [EN] Aiming at reducing pollutant emissions, hydrogen and fuel cell hybrid electric vehicles (FCVs) represent a promising technological solution. In this scenario, this paper proposes an adaptive energy management strategy (A-EMS) based on speed forecasting for a heavy-duty FCV, in order to achieve stable battery charge sustenance in realistic driving conditions. A validated and optimized fuel cell system model has been integrated into a complete vehicle model developed in the GT-Suite environment. A short-term velocity prediction layer based on a long short term memory (LSTM) neural network has been built in the A-EMS framework. The network has been trained and tested with realistic driving data simulated by GT-Real Drive for routes of the Trans-European Transport Network. The vehicle speed prevision has been realized over different forecasting horizons (5, 10, and 20 s). The adaptive equivalent consumption minimization strategy (A-ECMS) combined with short-term vehicle speed prediction is the A-EMS core algorithm of the presented work. Its results are here compared with the standard ECMS (S-ECMS) for four different driving cycles, including both standardized (HDDT) and realistic driving profiles. Three different European routes, with varying characteristics and from different countries, have been selected to test the proposed strategy in various conditions. The short-term prediction layer achieves satisfactory forecasting accuracy, with a RMSE ranging from 1.76 km/h to 13.37 km/h. The A-ECMS provides an improved by an order of magnitude battery charge sustenance, evaluated in terms of maximum battery state of charge (SoC) variation and fluctuation degree, with a hydrogen consumption increase ranging from 3.76% to 11.40% compared to the S-ECMS, for which the driving cycle is supposed to be known beforehand. As an example, in the HDDT cycle, the absolute maximum SoC variation and its fluctuation degree are lowered by about 76% and 79%, respectively. In conclusion, the proposed A-ECMS demonstrated that it is applicable for real driving conditions without prior knowledge of the driving cycle while improving battery charge sustaining for a FCV.This study was funded by the Generalitat Valenciana (Conselleria d'Innovacio, Universitats, Ciencia i Societat Digital) as a part of the DE-FIANCE research project (CIPROM/2021/039) through the PROMETEO funding program. Funding for open access charge: CRUE-Universitat Politecnica de Valencia.Piras, M.; De Bellis, V.; Malfi, E.; Novella Rosa, R.; López-Juárez, M. (2023). Adaptive ECMS based on speed forecasting for the control of a heavy-duty fuel cell vehicle for real-world driving. Energy Conversion and Management. 289. https://doi.org/10.1016/j.enconman.2023.11717828

    Liquid mixtures involving hydrogenated and fluorinated alcohols: thermodynamics, spectroscopy, and simulation

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    This article reports a combined thermodynamic, spectroscopic, and Computational study on the interactions and structure of binary mixtures of hydrogenated and fluorinated substances that simultaneously interact through strong hydrogen bonding. Four binary mixtures of hydrogenated and fluorinated alcohols have been studied, namely, (ethanol + 2,2,2-trifluoroethanol (TFE)), (ethanol + 2,2,3,3,4,4,4-heptafluoro-1-butanol), (1-butanol (BuOH) + TFE), and (BuOH + 2,23,4,4,4-heptafluoto-1-butanol). Excess molar volumes and vibrational spectra of all four binary mixtures have been measured as a function of composition at 298 K, and molecular dynamics simulations have been performed. The systems display a complex behavior when compared with mixtures of hydrogenated alcohols and mixtures of alkanes and perfluoroalkanes. The combined analysis of the results from different approaches indicates that this results from a balance between preferential hydrogen bonding between the hydrogenated and fluorinated alcohols and the unfavorable dispersion forces between the hydrogenated and fluorinated chains. As the chain length increases, the contribution of dispersion increases and overcomes the contribution of H-bonds. In terms of the liquid structure, the simulations suggest the possibility of segregation between the hydrogenated and fluorinated segments, a hypothesis corroborated by the spectroscopic results. Furthermore, a quantitative analysis of the infrared spectra reveals that the presence of fluorinated groups induces conformational changes in the hydrogenated chains from the usually preferred all-trans to more globular arrangements involving gauche conformations. Conformational rearrangements at the CCOH dihedral angle upon mixing are also disclosed by the spectra
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