1,272 research outputs found

    Microstructural optimization of unalloyed ductile cast irons with a ferritic matrix used in the manufacture of wind turbine rotors

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    The aim of this work was the microstructural optimization of cast irons with nodular graphite for the manufacture of wind turbine hubs, paying preferential attention to the geometry and distribution of graphite spheroids to ensure the required mechanical properties for this application. The target was pursued based upon microstructure-properties correlation, in an environment of great competitiveness and exigency marked by current international standards. The methodology followed consisted of the generation of knowledge from tailor-made industrial castings, followed by the analysis of their microstructures, in order to extract valuable conclusions for the production process through the use of statistical analysis. The approach method employed was a Fractional Design of Experiments (DOE) with 7 factors, 16 experiments and resolution IV. The samples from each experiment were cubes of identical geometry, and designed to match a surface-to-volume module equal to 4 cm (1.57 in) found as the highest values in real hubs of 3 MW power wind turbines. It is concluded that the use of nodulizers with traces of lanthanum favour the reduction of the volume fraction of pearlite, although La has proved not to promote the spherical shape of primary graphite. The negative effect of pre-inoculants containing SiC on the spheroidal morphology of graphite has also been verified, and also that low-Mn bearing scrap favours graphite formation and the reduction of the volume fraction of pearlite, in spite of being a carbide forming element. The whitening effect of Mn was minimized with low carbon equivalent melts

    Utilizando la metodología fitosociológica para diferenciar hábitats: un ejemplo con especies chilenas de Schinus (Anacardiaceae) en la Región de Aisén, Chile

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    Habitats of Schinus patagonicus and Schinus marchandii in the Chilean Patagonia were studied, in order to determinethe plant communities into these species growing and the primary or secondary character of them, to help establishthe conservation status of the two species. We worked with phytosociological methods to characterize floristic andvegetationaly the communities. The vegetation table is ordered with traditional methods, using differential species andwith multivariate statistical classification and ordination methods. The initial vegetation table provided 68 plant speciesof which 26 are introduced weed. In the biological spectrum dominated hemicryptophytes and minor phanerophytes andtherophytes. Traditional management of the vegetation table separated the Mutisio-Schinetum patagonicae (“clavel delaire” and “molle” scrub) and Colliguajo-Schinetum marchandii (“duraznillo” and “laura” steppe scrub) new associations that are described. Comparison of these two communities established that they are floristically very different and thattheir phytosociological affinity is low, the first is a secondary scrub community that replaces the deciduous patagonic“lenga” forest and the “ñire” scrub degraded by human action and the second, a primary steppe community. The abundantpresence of Mulinum spinosum differentiates degraded stages of these two communities specially the first. The secondarycharacter of the “clavel del aire” and “molle” community confirms the more aggressive and competitive position of Schinuspatagonicus, which ensures their survival as a species, but the primary character and the small size of the scrub of “laura”and “duraznillo” scrub also areal reduction of Schinus marchandii indicate that the conservation status of the latter speciesin Chile is poor.Se estudiaron los hábitats de Schinus patagonicus y Schinus marchandii en la Patagonia chilena, con el propósito dedeterminar las comunidades vegetales en que crecen y el carácter primario o secundario de ellas, para ayudar a establecerel estado de conservación de las dos especies. Se trabajó con metodología fitosociológica para caracterizar florística yvegetacionalmente las comunidades. La tabla de vegetación se ordenó con métodos tradicionales, utilizando especiesdiferenciales y estadísticos multivariables de clasificación y ordenación. La tabla fitosociológica inicial presentó 68 especiesvegetales siendo 26 de ellas malezas introducidas. En el espectro biológico predominaron hemicriptófitos y con menorimportancia, fanerófitos y terófitos. La ordenación tradicional separó las asociaciones Mutisio-Schinetum patagonicae(matorral de clavel del aire y molle) y Colliguajo-Schinetum marchandii (matorral estepario de duraznillo y laura) quese describen como nuevas. La comparación de estas dos comunidades permitió establecer que son florísticamente muydiferentes y que su afinidad fitosociológica es baja: la primera es una comunidad de matorral secundario que reemplazaal bosque de lenga y al matorral de ñire caducifolios degradados por la acción humana y la segunda, una comunidadesteparia primaria. La abundante presencia de Mulinum spinosum permite diferenciar estadios degradados para la primeray esteparios extremos para la segunda. El carácter secundario de la comunidad de clavel del aire y molle confirma la mayoragresividad y capacidad de competencia de Schinus patagonicus, lo que asegura su sobrevivencia como especie, pero elcarácter primario y el pequeño tamaño del área del matorral de duraznillo y laura, además de la reducción de tamaño deSchinus marchandii, indican que el estado de conservación de esta última especie en Chile es precario

    Olfactomedin‑like 2 A and B (OLFML2A and OLFML2B) expression profile in primates (human and baboon)

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    Background: The olfactomedin‑like domain (OLFML) is present in at least four families of proteins, including OLFML2A and OLFML2B, which are expressed in adult rat retina cells. However, no expression of their orthologous has ever been reported in human and baboon. Objective: The aim of this study was to investigate the expression of OLFML2A and OLFML2B in ocular tissues of baboons (Papio hamadryas) and humans, as a key to elucidate OLFML function in eye physiology. Methods: OLFML2A and OLFML2B cDNA detection in ocular tissues of these species was performed by RT‑PCR. The amplicons were cloned and sequenced, phylogenetically analyzed and their proteins products were confirmed by immunofluorescence assays. Results: OLFML2A and OLFML2B transcripts were found in human cornea, lens and retina and in baboon cornea, lens, iris and retina. The baboon OLFML2A and OLFML2B ORF sequences have 96% similarity with their human’s orthologous. OLFML2A and OLFML2B evolution fits the hypothesis of purifying selection. Phylogenetic analysis shows clear orthology in OLFML2A genes, while OLFML2B orthology is not clear. Conclusions: Expression of OLFML2A and OLFML2B in human and baboon ocular tissues, including their high simi‑ larity, make the baboon a powerful model to deduce the physiological and/or metabolic function of these proteins in the eye

    Micronucleus frequency and exposure to chemical mixtures in three Colombian mining populations

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    La industria minera colombiana ha experimentado un crecimiento significativo. Dependiendo de la escala y del mineral extraído, se generan mezclas químicas complejas que impactan la salud de las poblaciones ocupacionalmente expuestas y de las comunidades cercanas a los proyectos mineros. Cada vez hay más evidencias que sugieren que la inestabilidad cromosómica (CIN) es un vínculo importante entre el desarrollo de ciertas enfermedades y la exposición a mezclas complejas. Para comprender mejor los efectos de la exposición a mezclas complejas realizamos un estudio de biomonitorización en 407 individuos sanos de cuatro zonas: tres situadas en municipios que explotan sistemas mineros de diferente escala y una zona de referencia sin actividad minera. Se analizaron sistemas de minería a gran, mediana y pequeña escala en Montelíbano (Córdoba), minería artesanal y de pequeña escala (MAPE) en Nechí (Antioquia) y un sistema de minería cerrada en Aranzazu (Caldas). El área de referencia sin actividad minera se estableció en Montería (Córdoba). La ICP-MS midió la exposición multielemental en el cabello, y la NIC se evaluó mediante la técnica de micronúcleos en bloque de citocinesis (MNBN). La exposición a mezclas de elementos químicos fue comparable en trabajadores y residentes de las zonas mineras, pero significativamente superior en comparación con los individuos de referencia. En Montelíbano, el aumento de las frecuencias de MNBN se asoció con la exposición combinada a Se, Hg, Mn, Pb y Mg. Este patrón distintivo difirió significativamente de otras áreas. Específicamente, en Nechí, Cr, Ni, Hg, Se, y Mg emergieron como los principales contribuyentes a las frecuencias elevadas de MNBN. Por el contrario, una combinación de Hg y Ni desempeñó un papel en el aumento de MNBN en Aranzazu. Curiosamente, el Se se correlacionó consistentemente con el aumento de las frecuencias de MNBN en todas las áreas mineras activas. Los elementos químicos en Montelíbano muestran un rango más amplio en comparación con otras zonas mineras, reflejando las características de la minería de alto impacto y a gran escala en la zona. Esta investigación proporciona información valiosa sobre los efectos de la exposición a mezclas químicas, subrayando la importancia de emplear este enfoque en la evaluación del riesgo de las comunidades, especialmente las de las zonas residenciales. © 2023 Los autoresThe Colombian mining industry has witnessed significant growth. Depending on the scale and mineral extracted, complex chemical mixtures are generated, impacting the health of occupationally exposed populations and communities near mining projects. Increasing evidence suggests that chromosomal instability (CIN) is an important link between the development of certain diseases and exposure to complex mixtures. To better understand the effects of exposure to complex mixtures we performed a biomonitoring study on 407 healthy individuals from four areas: three located in municipalities exploiting different-scale mining systems and a reference area with no mining activity. Large, medium, and small-scale mining systems were analyzed in Montelibano (Córdoba), artisanal and small-scale mining (ASGM) in Nechí (Antioquia), and a closed mining system in Aranzazu (Caldas). The reference area with no mining activity was established in Montería (Córdoba). ICP-MS measured multi-elemental exposure in hair, and CIN was evaluated using the cytokinesis-block micronucleus technique (MNBN). Exposure to mixtures of chemical elements was comparable in workers and residents of the mining areas but significantly higher compared to reference individuals. In Montelibano, increased MNBN frequencies were associated with combined exposure to Se, Hg, Mn, Pb, and Mg. This distinct pattern significantly differed from other areas. Specifically, in Nechí, Cr, Ni, Hg, Se, and Mg emerged as the primary contributors to elevated frequencies of MNBN. In contrast, a combination of Hg and Ni played a role in increasing MNBN in Aranzazu. Interestingly, Se consistently correlated with increased MNBN frequencies across all active mining areas. Chemical elements in Montelibano exhibit a broader range compared to other mining zones, reflecting the characteristics of the high-impact and large-scale mining in the area. This research provides valuable insights into the effects of exposure to chemical mixtures, underscoring the importance of employing this approach in the risk assessment of communities, especially those from residential areas. © 2023 The Author

    HGF, IL-1α, and IL-27 are robust biomarkers in early severity stratification of COVID-19 patients

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    © 2021 by the authors.Pneumonia is the leading cause of hospital admission and mortality in coronavirus disease 2019 (COVID-19). We aimed to identify the cytokines responsible for lung damage and mortality. We prospectively recruited 108 COVID-19 patients between March and April 2020 and divided them into four groups according to the severity of respiratory symptoms. Twenty-eight healthy volunteers were used for normalization of the results. Multiple cytokines showed statistically significant differences between mild and critical patients. High HGF levels were associated with the critical group (OR = 3.51; p < 0.001; 95%CI = 1.95–6.33). Moreover, high IL-1α (OR = 1.36; p = 0.01; 95%CI = 1.07–1.73) and low IL-27 (OR = 0.58; p < 0.005; 95%CI = 0.39–0.85) greatly increased the risk of ending up in the severe group. This model was especially sensitive in order to predict critical status (AUC = 0.794; specificity = 69.74%; sensitivity = 81.25%). Furthermore, high levels of HGF and IL-1α showed significant results in the survival analysis (p = 0.033 and p = 0.011, respectively). HGF, IL-1α, and IL 27 at hospital admission were strongly associated with severe/critical COVID-19 patients and therefore are excellent predictors of bad prognosis. HGF and IL-1α were also mortality biomarkers.This work was supported by the Carlos III Health Institute (Grant COV20/00491)

    HGF, IL-1α, and IL-27 Are Robust Biomarkers in Early Severity Stratification of COVID-19 Patients

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    Producción CientíficaPneumonia is the leading cause of hospital admission and mortality in coronavirus disease 2019 (COVID-19). We aimed to identify the cytokines responsible for lung damage and mortality. We prospectively recruited 108 COVID-19 patients between March and April 2020 and divided them into four groups according to the severity of respiratory symptoms. Twenty-eight healthy volunteers were used for normalization of the results. Multiple cytokines showed statistically significant differences between mild and critical patients. High HGF levels were associated with the critical group (OR = 3.51; p < 0.001; 95%CI = 1.95–6.33). Moreover, high IL-1α (OR = 1.36; p = 0.01; 95%CI = 1.07–1.73) and low IL-27 (OR = 0.58; p < 0.005; 95%CI = 0.39–0.85) greatly increased the risk of ending up in the severe group. This model was especially sensitive in order to predict critical status (AUC = 0.794; specificity = 69.74%; sensitivity = 81.25%). Furthermore, high levels of HGF and IL-1α showed significant results in the survival analysis (p = 0.033 and p = 0.011, respectively). HGF, IL-1α, and IL 27 at hospital admission were strongly associated with severe/critical COVID-19 patients and therefore are excellent predictors of bad prognosis. HGF and IL-1α were also mortality biomarkers.Instituto de Salud Carlos III (grant COV20/00491

    Patógenos de importancia clínica

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    PublishedEl presente libro Patógenos de importancia clínica: Inves­tigaciones Recientes en el Valle del Cauca nace como una iniciativa para socializar los resultados obtenidos en los tra­bajos de investigación más recientes de los miembros del Grupo de Investigación en genética, fisiología y metabolis­mo –GEFIME– de la Universidad Santiago de Cali. Estas investigaciones involucran patógenos que son importantes agentes causales de infecciones y de alto impacto en la salud pública en la ciudad de Cali y en el Valle del Cauca. Este libro consta de cinco capítulos con trabajos de investiga­ción en bacterias resistentes a los antibióticos como Staphylo­coccus aureus y Mycobacterium tuberculosis y su comporta­miento epidemiológico en ambientes intrahospitalarios y en poblaciones, respectivamente. En el Capítulo 3 se presenta un estudio epidemiológico que establece la presencia del virus del papiloma humano (VPH) en mucosa oral y su relación con el desarrollando cáncer oral y en el Capítulo 4 se presenta una investigación realizada con moléculas efectoras (alarmona pp­Gpp y la proteína DksA) de Salmonella enterica serovar Typhi­murium y su influencia en la patogenicidad y la formación de biopelículas in-vitro

    Can the Cytokine Profile According to ABO Blood Groups Be Related to Worse Outcome in COVID-19 Patients? Yes, They Can

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    Producción CientíficaSevere status of coronavirus disease 2019 (COVID-19) is extremely associated to cytokine release. Moreover, it has been suggested that blood group is also associated with the prevalence and severity of this disease. However, the relationship between the cytokine profile and blood group remains unclear in COVID-19 patients. In this sense, we prospectively recruited 108 COVID-19 patients between March and April 2020 and divided according to ABO blood group. For the analysis of 45 cytokines, plasma samples were collected in the time of admission to hospital ward or intensive care unit and at the sixth day after hospital admission. The results show that there was a risk of more than two times lower of mechanical ventilation or death in patients with blood group O (log rank: p = 0.042). At first time, all statistically significant cytokine levels, except from hepatocyte growth factor, were higher in O blood group patients meanwhile the second time showed a significant drop, between 20% and 40%. In contrast, A/B/AB group presented a maintenance of cytokine levels during time. Hepatocyte growth factor showed a significant association with intubation or mortality risk in non-O blood group patients (OR: 4.229, 95% CI (2.064–8.665), p < 0.001) and also was the only one bad prognosis biomarker in O blood group patients (OR: 8.852, 95% CI (1.540–50.878), p = 0.015). Therefore, higher cytokine levels in O blood group are associated with a better outcome than A/B/AB group in COVID-19 patients.Instituto de Salud Carlos III (grant COV20/00491)Junta de Castilla y León (grant 18IGOF

    OBSERVATORIO TERRITORIAL Y AMBIENTAL ALENTEJO, EXTREMADURA, CENTRO (OTALEX C): DE GIS A IDE.

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    In the scope of the Spain-Portugal INTERREG projects and FEDER funded POCTEP program, OTALEX C (Territorial and Environmental Monitoring Alentejo Extremadura Center) project aims at studying of various territorial, socioeconomic and environmental indicators. It is the fundamental objective of this project, to develop a geo-portal accessible via internet, for anyone, so that the information will be useful in making decisions related to land use and therefore sustainable development of the environment. Under this general framework over the past fifteen years, we have developed different projects that have set the standardization of data between Portugal and Spain, also was designed GIS systems, and developed regional models and indicator systems, culminating in the current Spatial Data Infrastructure SDI-OTALEX C

    PERSPECTIVA PSICOSOCIAL DE LOS DERECHOS HUMANOS

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    Hoy en día es imprescindible abordar el problema de los derechos desde una perspectiva holística que integre la posición que el individuo ocupa en la sociedad y el impacto de los hechos sociales sobre su persona. Esta perspectiva va por lo tanto más allá del enfoque clásico de las violaciones a los derechos civiles y políticos de los ciudadanos sino, también incluye sus derechos económicos, sociales y culturales. Cualquier enfoque de tipo holístico debe entender al ser humano en su ambiente, social, cultural, natural y en función a todas las estructuras existentes, por más sutiles que sean o invisibles que parezcan. Precisamente este libro permite apreciar la dimensión amplia y compleja del ser en sociedad y las interacciones que de ambas partes se generan y las ramificaciones que producen. No es un ejercicio fácil y los editores de este volumen han logrado un salto cuántico al poder congregar en un solo espacio miradas que en otras circunstancias podrían haber sido opuestas y hasta contrarias a nuestra comprensión de problemas que, en efecto, tienen raíces comunes. El libro está dividido en 5 secciones, El espíritu de los tiempos actuales y los Derechos Humanos, Construcción ciudadana y ejercicio de los Derechos Humanos, Violaciones a Derechos Humanos, victimizaciones y su atención, Ejercicio de los Derechos Humanos y situaciones disruptivas y Defensa y defensores de Derechos Humanos.Manuel Gutiérrez Romero Jessica Ruiz Magañ
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