30 research outputs found

    Determinación de carbono orgánico en materias primas cerámicas en presencia de siderita, FeCO3

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    La materia orgánica es una de las impurezas presentes en las materias primas utilizadas en la fabricación de pavimentos y revestimientos cerámicos. Durante el proceso de cocción, el carbono orgánico (Corgánico) puede producir la aparición de un núcleo negro conocido como “corazón negro”, que puede causar defectos en el producto final. Las materias primas cerámicas contienen Corgánico a nivel de mg·kg-1 (procedente de la materia orgánica) y carbono inorgánico (Cinorgánico) a nivel de porcentaje (procedente de siderita (FeCO3), calcita (CaCO3) y dolomita (CaMg(CO3)2), principalmente). La presencia de siderita puede interferir en la determinación de Corgánico puesto que su temperatura de descomposición difiere muy poco de la temperatura de determinación del Corgánico, no ocurriendo lo mismo con la calcita y la dolomita, cuyas temperaturas de descomposición son superiores. Existen diversos métodos para la determinación de Corgánico en muestras sólidas, aunque no se han encontrado estudios cuantitativos sobre dicha determinación en presencia de siderita. En este trabajo se han desarrollado dos métodos para determinar Corgánico en materias primas y composiciones cerámicas mediante análisis elemental, en presencia de siderita, que pueden ser utilizados en el control de la aparición de corazón negro en baldosas cerámicas. La metodología desarrollada presenta bajos límites de cuantificación e incertidumbres, siendo un método rápido y preciso.Organic material is one of the impurities present in the raw materials used in the manufacture of ceramic floor and wall tiles. During the firing process, organic carbon (Corganic) can give rise to the appearance of what is known as "black core" inside the material, which can produce defects in the final product. Ceramic raw materials contain Corganic in the order of mg•kg-1 (from organic material) and inorganic carbon (Cinorganic) in the order of a percentage (mainly from siderite – FeCO3, calcite – CaCO3, and dolomite – CaMg(CO3)2). The presence of siderite can interfere in the determination of Corganic, since its decomposition temperature differs only slightly from the determination temperature of Corganic; this is not the case of calcite and dolomite, which decompose at higher temperatures. There are several different methods for determining Corganic in solid samples, although no quantitative studies on such determination in the presence of siderite were found. In this study two methods were developed for determining Corganic in raw materials and ceramic compositions by means of elemental analysis, in the presence of siderite, which can be used to control the appearance of black core in ceramic floor tiles. The method developed here offers low limits of quantification and uncertainties, while at the same time it is fast and precise

    Monitoring of bluetongue virus in zoo animals in Spain, 2007–2019

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    Bluetongue (BT) is an emerging and re-emerging communicable vector-borne disease of animal health concern. A serosurvey was performed to assess exposure to BT virus (BTV) in zoo animals in Spain and to determine the dynamics of seropositivity in longitudinally sampled individuals during the study period. Serum samples were collected from 241 zoo animals belonging to 71 different species in five urban zoos (A-E) in Spain between 2007 and 2019. Twenty-four of these animals were longitudinally surveyed at three of the sampled zoos (zoos B, C and E) during the study period. Anti-BTV antibodies were found in 46 (19.1%; 95% CI: 14.1-24.1) of the 241 captive animals analysed by commercial ELISA. A virus neutralization test confirmed specific antibodies against BTV-1 and BTV-4 in 25 (10.7%; 95% CI: 6.7-14.6) and five (3.0%; 95% CI: 0.3-4.0) animals, respectively. Two of the 24 longitudinally sampled individuals (one African elephant (Loxodanta africana) and one aoudad (Ammotragus lervia)) showed anti-BTV antibodies at all samplings, whereas seroconversions were detected in one mouflon (Ovis aries musimon) in 2016, and one Asian elephant (Elephas maximus) in 2019. To the best of the authors' knowledge, this is the first large-scale survey on BTV conducted in both artiodactyl and non-artiodactyl zoo species worldwide. The results confirm BTV exposure in urban zoo parks in Spain, which could be of animal health and conservation concern. Circulation of BTV was detected in yearling animals in years when there were no reports of BTV outbreaks in livestock. Surveillance in artiodactyl and non-artiodactyl zoo species could be a valuable tool for epidemiological monitoring of BTV.info:eu-repo/semantics/acceptedVersio

    Nivel de independencia en la vida diaria y plasticidad cognitiva en la vejez

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    Recent research provides evidence that an active lifestyle is associated with a high level of plasticity, which in turn is related to a reduced probability of cognitive deterioration and decline (Calero, Navarro & Muñoz, 2007). Activities of daily living (ADL) constitute one of the variables currently considered to be an indicator of dependence/independence in old age and which is associated with cognitive and physical decline. The aim of the present study was to analyse the relation between ADL and cognitive plasticity in old age. Sixtythree elderly participants were evaluated using diverse measures of ADL levels and two techniques for evaluating learning potential. Results showed that a higher level of cognitive plasticity was associated with greater functional independence in daily living.En la actualidad, un estilo de vida activo se asocia con un alto nivel de plasticidad cognitiva que a su vez se relaciona con una menor probabilidad de deterioro y declive cognitivo (Calero, Navarro y Muñoz, 2007). Las actividades de la vida diaria (AVD) es una de las variables consideradas indicadoras de dependenciaindependencia en la vejez que se asocia al deterioro cognitivo y físico. El objetivo de esta investigación es analizar la relación entre las AVD y la plasticidad cognitiva en la vejez. Han participado 63 ancianos evaluados con distintas medidas de autonomía/dependencia y con dos técnicas de evaluación del potencial de aprendizaje. Los resultados muestran que un mayor nivel de plasticidad cognitiva se asocia a una mayor independencia funcional en la vida diaria

    Characterization of constricted fruit (ctf) Mutant Uncovers a Role for AtMYB117/LOF1 in Ovule and Fruit Development in Arabidopsis thaliana

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    Pistil and fruit morphogenesis is the result of a complex gene network that is not yet fully understood. A search for novel genes is needed to make a more comprehensive model of pistil and fruit development. Screening for mutants with alterations in fruit morphology generated by an activation tagging strategy resulted in the isolation of the ctf (constricted fruit) mutant. It is characterized by a) small and wrinkled fruits, with an enlarged replum, an amorphous structure of the septum and an irregular distribution of ovules and seeds; b) ectopic carpelloid structures in sepals bearing ovule-like structures and c) dwarf plants with curled rosette leaves. The overexpressed gene in ctf was AtMYB117, also named LOF1 (LATERAL ORGAN FUSION1). AtMYB117/LOF1 transcripts were localized in boundary regions of the vegetative shoot apical meristem and leaf primordia and in a group of cells in the adaxial base of petioles and bracts. Transcripts were also detected in the boundaries between each of the four floral whorls and during pistil development in the inner of the medial ridges, the placenta, the base of the ovule primordia, the epidermis of the developing septum and the outer cell layers of the ovule funiculi. Analysis of changes of expression of pistil-related genes in the ctf mutant showed an enhancement of SHATTERPROOF1 (SHP1) and SHP2 expression. All these results suggest that AtMYB117/LOF1 is recruited by a variety of developmental programs for the establishment of boundary regions, including the development of floral organs and the initiation of ovule outgrowth

    Complement system activation contributes to the ependymal damage induced by microbial neuraminidase

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    Background In the rat brain, a single intracerebroventricular injection of neuraminidase from Clostridium perfringens induces ependymal detachment and death. This injury occurs before the infiltration of inflammatory blood cells; some reports implicate the complement system as a cause of these injuries. Here, we set out to test the role of complement. Methods The assembly of the complement membrane attack complex on the ependymal epithelium of rats injected with neuraminidase was analyzed by immunohistochemistry. Complement activation, triggered by neuraminidase, and the participation of different activation pathways were analyzed by Western blot. In vitro studies used primary cultures of ependymal cells and explants of the septal ventricular wall. In these models, ependymal cells were exposed to neuraminidase in the presence or absence of complement, and their viability was assessed by observing beating of cilia or by trypan blue staining. The role of complement in ependymal damage induced by neuraminidase was analyzed in vivo in two rat models of complement blockade: systemic inhibition of C5 by using a function blocking antibody and testing in C6-deficient rats. Results The complement membrane attack complex immunolocalized on the ependymal surface in rats injected intracerebroventricularly with neuraminidase. C3 activation fragments were found in serum and cerebrospinal fluid of rats treated with neuraminidase, suggesting that neuraminidase itself activates complement. In ventricular wall explants and isolated ependymal cells, treatment with neuraminidase alone induced ependymal cell death; however, the addition of complement caused increased cell death and disorganization of the ependymal epithelium. In rats treated with anti-C5 and in C6-deficient rats, intracerebroventricular injection of neuraminidase provoked reduced ependymal alterations compared to non-treated or control rats. Immunohistochemistry confirmed the absence of membrane attack complex on the ependymal surfaces of neuraminidase-exposed rats treated with anti-C5 or deficient in C6. Conclusions These results demonstrate that the complement system contributes to ependymal damage and death caused by neuraminidase. However, neuraminidase alone can induce moderate ependymal damage without the aid of complement

    White Paper 1: New foundations for a sustainable global society

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    Coordinación: Eduardo Moyano Estrada; Tomás García Azcárate.This volume is focused on the axis “New foundations for a sustainable global society”, and refers to the important process of global change that affects all dimensions of society, disrupting the context in which scientific work has been developed in recent decades. It is a process of change not comparable to what happened decades ago, mainly due to its breadth, multidimensionality and interdependence, and also to the fact that this process manifests itself simultaneously in many areas, territories and social groups. Its analysis therefore requires carrying out a convergence exercise between areas and lines of research, betting on a multidisciplinary approach, since both “globalization” and “sustainability” are, concepts that affect society, as a whole.Peer reviewe

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

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    Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

    Development of a perceptual colorimeter based on a conventional CCD camera with more than three color channels

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    In order to improve the precision of colorimeters based on a digital image capture device, we increased the number of acquisition channels by using a supplementary filter placed in front of the color camera and taking two images of the scene: one without the filter (3 RGB channels) and one with the filter (3 different UVW channels). We selected a wide-band cyan filter that increases the transmission of spectral zones common to the three pseudo-color matching functions of the CCD camera and the spectral transmission of the channel with the lowest sensitivity. This six-channel color measurement instrument shows an improvement in the precision level compared with a conventional three-channel system, obtaining a better Vora factor (greater than 0.96), color quality factor (greater than 0.95) and color reproduction index (greater than 96%). From the colorimetric values obtained with the six-channel system we developed a perceptual colorimeter by applying different color appearance models (ATD, Hunt’91, CIELAB, LLAB, Hunt’94 and CIECAM02). The results obtained with the colorimeter developed showed a good performance for the perceptual parameters in comparison with a conventional telespectroradiometer, especially when Hunt’94 and CIECAM02 models were applied.This research was supported by the Spanish Ministry of Science and Technology (Ministerio de Ciencia y Tecnología) by means of grants PDI2002-00118 and PIR1995-0587-OP
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