75 research outputs found

    Zircon Dates Long-Lived Plume Dynamics in Oceanic Islands

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    In this contribution we report the first systematic study of zircon U-Pb geochronology and δ 18O-εHf(t) isotope geochemistry from 10 islands of the hot-spot related Galapagos Archipelago. The data extracted from the zircons allow them to be grouped into three types: (a) young zircons (0–∼4 Ma) with εHf(t) (∼5–13) and δ 18O (∼4–7) isotopic mantle signature with crystallization ages dating the islands, (b) zircons with εHf(t) (∼5–13) and δ 18O (∼5–7) isotopic mantle signature (∼4–164 Ma) which are interpreted to date the time of plume activity below the islands (∼164 Ma is the minimum time of impingement of the plume below the lithosphere), and (c) very old zircons (∼213–3,000 Ma) with mostly continental (but also juvenile) εHf(t) (∼−28–8) and δ 18O (∼5–11) isotopic values documenting potential contamination from a number of sources. The first two types with similar isotopic mantle signature define what we call the Galápagos Plume Array (GPA). Given lithospheric plate motion, this result implies that GPA zircon predating the Galápagos lithosphere (i.e., >14–164 Ma) formed and were stored at sublithospheric depths for extended periods of time. In order to explain these observations, we performed 2D and 3D thermo-mechanical numerical experiments of plume-lithosphere interaction which show that dynamic plume activity gives rise to complex asthenospheric flow patterns and results in distinct long-lasting mantle domains beneath a moving lithosphere. This demonstrates that it is physically plausible that old plume-derived zircons survive at asthenospheric depths below ocean islands.German Research Foundation (DFG) RO4174/3-1 RO4174/3-3Ministry of Science and Innovation, Spain (MICINN)Spanish GovernmentEuropean Commission PID2019-105625RB-C21 PY20_00550European Research Council (ERC) European Commission MAGMA 77114

    Compositional Evolution of the Variscan Intra-Orogenic Extensional Magmatism in the Valencia del Ventoso Plutonic Complex, Ossa-Morena Zone (SW Iberia): A View from Amphibole Compositional Relationships

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    The Ossa-Morena Zone (OMZ), SW Iberia, has numerous Lower Carboniferous compositionally zoned plutons that formed in a Variscan intra-orogenic extensional setting. This magmatism shows a wide compositional variation comprising alkaline, transitional, and calc-alkaline suites. The calc-alkaline suite was produced by hybridization of alkaline magmas with felsic melts generated by crustal anatexis related to the intrusion of mafic magmas in the middle crust. In this work, we present a textural and mineralogical study of the Variscan Valencia del Ventoso main pluton from the OMZ to track the compositional evolution of magmas during hybridization using constraints from amphibole compositions and to determine the P-T conditions of emplacement using amphibolebased thermobarometry. This pluton exhibits reverse zoning with an inner facies containing alkaline dolerites, gabbros, and quartz diorites, an intermediate facies with transitional diorites, and an outer facies with calc-alkaline quartz diorites to monzogranites. Magmas from the intermediate and border facies crystallized under oxidizing conditions at relatively low temperatures (range: 640–760 ◦C) and ca. 280–300 MPa, implying near H2O-saturated conditions. These rock facies show mineralogical evidence of hybridization between alkaline to mildly alkalic and calc-alkaline magmas. The former is inferred from the occurrence of antecrysts of labradorite-andesine, high-Ti pargasite-hastingsite, and biotite with deficiency in tetrahedral-site occupancy, a distinctive feature of biotite from the inner facies alkaline dolerites. This contrasts with later crystallization from the calc-alkaline magma of andesine-oligoclase, low-Ti magnesiohornblende-edenite, and biotite with full tetrahedral-site occupancy. Constraints from amphibole-melt compositional relationships in antecrystic high-Ti amphibole suggest that the alkaline magmatic component could have a high- to ultra-K affinity.Ministerio de Economía y Competitividad (Gobierno de España), CGL2017-84469-

    Lu-Hf ratios of crustal rocks and their bearing on zircon Hf isotope model ages: The effects of accessories

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    All other factors being equal, the calculation of zircon Hf two stage model ages (TDM Hf) depends on the par- ticular Lu/Hf value assumed for the magmatic source, the effect being more pronounced as the age difference between zircon and magmatic source increases. It is generally considered that the Lu/Hf measured in the zircon- hosting rock does not represent the composition of the source because of potential garnet or zircon fractionation. Accordingly, most authors either assume a single fixed value for Lu/Hfsource, often Lu/Hf ≈ 0.079 to 0.108, or use two alternative models, one for felsic sources, often Lu/Hf ≈ 0.09, and the other for mafic sources, often Lu/ Hf ≈ 0.165. In contrast with these opinions, however, here we show that partial melting of peraluminous sources causes little decoupling of Lu from Hf because of similar solubilities of zircon and monazite. Furthermore, the effects of residual garnet are largely compensated by the numerous zircon inclusions that garnet and other residual minerals almost always contain. Partial melting of metaluminous sources may sig- nificantly decouple Lu from Hf if allanite and/or titanite are not present in the source, but the effect decreases as the melt fraction increases. Similarly, fractional crystallization of metaluminous magmas may decouple Lu from Hf if amphibole or clinopyroxene begin to crystallize before zircon saturation. The Lu/Hf distribution in 4784 rocks from different regions and ages is lognomal rather than normal, and the calculated medians, i.e. the maximum of the probability density function for the logarithmically transformed Lu/Hf, are Lu/Hfmafic rocks ≈ 0.08, Lu/Hffelsic rocks ≈ 0.05, i.e. notably lower than the above-mentioned felsic and mafic magmatic source averages. Magmatic sources may be remarkably heterogeneous with respect to Lu/Hf. Our calculations show that fixed Lu/Hfsource values translate the Lu/Hf heterogeneity of the source to the TDM Hf thus producing an artificial distribution of model ages that may be erroneously interpreted as different episodes of crustal growth. Therefore, we propose that the best strategy to calculate two stage Hf model ages of zircon is to use the analytically determined whole-rock Lu/Hf ratio as a proxy of the source. In the case of detrital or inherited zircons, for which no whole-rock information is available, it is advisable first to determine whether they come from a mafic or felsic rock by interpreting cathodoluminescence images, Th/U ratios and other chemical parameters, and then venture an estimate of the Lu/Hfsource from the SiO2 average

    Precise Measurement of Magnesium Isotopes in Fe-Mg Minerals Using a Multi-collector SHRIMP Ion Microprobe

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    The distribution of Mg isotopes in minerals is becoming increasingly relevant in Earth science. Usually, they are determined by dissolving mineral concentrates and, after purifying Mg with ion exchange resins, analysing the resulting solutions by TIMS or, most often, MC-ICP-MS. When applied to individual minerals, these methods are slow and prone to contamination from impurities in the concentrates, inconveniences that may be avoided using spot analysis techniques such as LA-MC-ICP-MS or SIMS, albeit at the price of a large instrumental mass fractionation (IMF) and isobaric interferences, most prominent in the former. Here, we studied the potential of the multi-collector SHRIMP II ion microprobe for measuring Mg isotopes in Fe-Mg silicates and oxides. We found that, when corrected for the divergence of the Mg ion paths within the sample chamber caused by the Earth’s magnetic field, the SHRIMP’s IMF overwhelmingly depends on the mineral species, and the effects of variable chemical composition are negligible. We propose that the IMF is caused by the force constant difference, ΔF, between "hard" and "soft" bonds linking the ions of the studied element to the mineral lattice. Given that ΔF is a constant for each mineral species, we calculated IMF-correction factors for the most common Mg-bearing minerals. The thus-calculated correction factors permit the analysis in the same session, and with reasonable accuracy (within ~0.3‰ of the δ26Mg determined by SN-MC-ICP-MS analyses of concentrates), of samples from different mineral species, facilitating the application of Mg isotopes to terrestrial studies.Andalucian-FEDER grant P18-FR-1696Spanish grant PID2020-114872GB-I0

    Inhibition of ATG3 ameliorates liver steatosis by increasing mitochondrial function

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    Non-alcoholic fatty liver disease (NAFLD) is a major health threat in both developed and developing countries and is a precursor of the more advanced liver diseases, including non-alcoholic steatohepatitis (NASH), cirrhosis, and liver cancer. Currently, understanding the multiple and complex molecular pathways implicated in NAFLD onset and progression is a major priority. The transcription factor p63, which belongs to a family comprising p53, p63, and p73,1 is one of many factors that contributes to the development of liver steatosis. The role of p63 as a tumor suppressor and in cell maintenance and renewal is well studied, but we have recently reported that it is also relevant in the control of lipid metabolism.2 p63 encodes multiple isoforms that can be grouped into 2 categories; isoforms with an acidic transactivation domain (TA) and those without this domain (domain negative). The TAp63α isoform is elevated in the liver of animal models of NAFLD as well as in liver biopsies from obese patients with NAFLD. Furthermore, downregulation of p63α in the liver attenuates liver steatosis in diet-induced obese (DIO) mice, while the activation of TAp63α increases hepatic fat content, mediated by the activation of IKKβ and endoplasmic reticulum stress.2 A specialized form of autophagy that degrades lipid droplets, termed “lipophagy”, is a major pathway of lipid mobilization in hepatocytes. Lipophagy is elevated in hepatoma cells upon exposure to free fatty acids,3 and reduces the fatty acid load in mouse hepatocytes.4 Its impairment has been associated with the development of fatty liver and insulin resistance3,5; in contrast, the autophagic flux is increased during the activation of hepatic stellate cells.6 In the present study, we used an unbiased proteomics approach to gain insight into novel proteins modulating lipid metabolism in the liver of mice with genetic knockdown or overexpression of TAp63α. We found that autophagy-related gene 3 (ATG3) was upregulated by TAp63α activation and downregulated after p63α inhibition. ATG3 is elevated in several animal models of NAFLD and in the liver of patients with NAFLD. Genetic overexpression of ATG3 increased the lipid load in hepatocytes, while its repression alleviated TAp63α- and diet-induced steatosis. ATG3 exerted its role in lipid metabolism by regulating SIRT1 and mitochondrial function. Collectively, these findings identify ATG3 as a novel factor implicated in the development of steatosisThis work has been supported by grants from FEDER/Ministerio de Ciencia, Innovación y Universidades-Agencia Estatal de Investigación (PA: RTI2018-095134-B-100; DS and LH: SAF2017-83813-C3-1-R; MLMC: RTC2019-007125-1; CD: BFU2017-87721; ML: RTI2018–101840-B-I00; GS; PID2019-104399RB-I00; RN: RTI2018-099413-B-I00 and RED2018-102379-T; MLMC: SAF2017-87301-R; TCD: RTI2018-096759-A-100), FEDER/Instituto de Salud Carlos III (AGR: PI19/00123), Xunta de Galicia (ML: 2016-PG068; RN: 2015-CP080 and 2016-PG057), Fundación BBVA (RN, GS and MLM), Proyectos Investigación en Salud (MLMC: DTS20/00138), Sistema Universitario Vasco (PA: IT971-16); Fundación Atresmedia (ML and RN), Fundación La Caixa (M.L., R.N. and M.C.), Gilead Sciences International Research Scholars Program in Liver Disease (MVR), Marató TV3 Foundation (DS: 201627), Government of Catalonia (DS: 2017SGR278) and European Foundation for the Study of Diabetes (RN and GS). This research also received funding from the European Community’s H2020 Framework Programme (ERC Synergy Grant-2019-WATCH- 810331, to RN, VP and MS). Centro de Investigación Biomédica en Red (CIBER) de Fisiopatología de la Obesidad y Nutrición (CIBERobn), Centro de Investigación Biomédica en Red (CIBER) de Enfermedades Hepáticas y Digestivas (CIBERehd) and CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERdem). CIBERobn, CIBERehd and CIBERdem are initiatives of the Instituto de Salud Carlos III (ISCIII) of Spain which is supported by FEDER funds. We thank MINECO for the Severo Ochoa Excellence Accreditation to CIC bioGUNE (SEV-2016-0644)S

    Ciencia y profesión : el farmacéutico en la historia

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    474 páginas. Versiones pdf / epubLas IV Jornadas Científicas de la Sociedad de Docentes Universitarios de Historia de la Farmacia (SDUHFE) se celebraron en la Sede de La Rábida en junio de 2016. Esta obra presenta diversas investigaciones y comunicaciones, con varias temáticas que pueden desglosarse en cuatro bloques: 1) En un primer grupo podemos considerar todos los capítulos que abordan la historia de los colegios farmacéuticos así como los avatares de la profesión. Se da cuenta en la provincia de Sevilla de las dificultades del Colegio de Farmacéuticos en el periodo de la Guerra Civil y la Posguerra (1936-1949), del proceso de colegiación obligatoria a partir de 1916, pinceladas históricas sobre los farmacéuticos cántabros del siglo XIX, del Colegio de Farmacéuticos de Filipinas a finales del XIX, de los conflictos de los farmacéuticos en las reuniones sanitarias de mitad del XX, y del papel de los farmacéuticos titulares en la potabilización de las aguas de consumo en Plentzia (Vizcaya). 2) Podemos destacar también todos los trabajos que giran en torno a diferentes medicamentos y productos farmacéuticos, entre ellos estudios históricos sobre piedras preciosas, medicamentos para tratar heridas, quina contra las tercianas, opio, alexifármacos, medicamentos homeopáticos, talidomida o curiosos productos como el Licor del Polo. 3) El papel de los laboratorios farmacéuticos como la Casa Nestlé durante la Guerra Civil española y el franquismo, diferentes laboratorios onubenses durante este mismo periodo, el papel del Instituto de Higiene Militar y la experimentación con insecticidas clorados sintéticos en la posguerra española, aglutinan el tercer cuerpo temático. 4) Finalmente, podemos destacar los trabajos que tienen una componente publicitaria, divulgadora y social entre los que cabe destacar el estudio del NO-DO y los diferentes noticieros y documentales sobre temas farmacéuticos que resultan muy ilustrativos. La propaganda farmacéutica desarrollada en la revista Matronas, el inventario del patrimonio farmacéutico catalán, junto a la percepción social de la farmacia a través de las fallas valencianas conforma este último grupo

    Discourse Analysis and Terminology in Languages for Specific Purposes

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    Aquest importantíssim recull conté estudis i reflexions sobre temes rellevants en la recerca sobre LSP: anglès mèdic, el llenguatge de la publicitat i periodístic, telecomunicacions i terminologia informàtica, llenguatge comercial i jurídic... Malgrat que gran part dels treballs aplegats es refereixen a l'anglès, també hi ha que tracten l'alemany, francès i altres llengües. Conté textos en anglès, francés, portuguès i castellà

    Role of age and comorbidities in mortality of patients with infective endocarditis

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    [Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

    Clustering COVID-19 ARDS patients through the first days of ICU admission. An analysis of the CIBERESUCICOVID Cohort

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    Background Acute respiratory distress syndrome (ARDS) can be classified into sub-phenotypes according to different inflammatory/clinical status. Prognostic enrichment was achieved by grouping patients into hypoinflammatory or hyperinflammatory sub-phenotypes, even though the time of analysis may change the classification according to treatment response or disease evolution. We aimed to evaluate when patients can be clustered in more than 1 group, and how they may change the clustering of patients using data of baseline or day 3, and the prognosis of patients according to their evolution by changing or not the cluster.Methods Multicenter, observational prospective, and retrospective study of patients admitted due to ARDS related to COVID-19 infection in Spain. Patients were grouped according to a clustering mixed-type data algorithm (k-prototypes) using continuous and categorical readily available variables at baseline and day 3.Results Of 6205 patients, 3743 (60%) were included in the study. According to silhouette analysis, patients were grouped in two clusters. At baseline, 1402 (37%) patients were included in cluster 1 and 2341(63%) in cluster 2. On day 3, 1557(42%) patients were included in cluster 1 and 2086 (57%) in cluster 2. The patients included in cluster 2 were older and more frequently hypertensive and had a higher prevalence of shock, organ dysfunction, inflammatory biomarkers, and worst respiratory indexes at both time points. The 90-day mortality was higher in cluster 2 at both clustering processes (43.8% [n = 1025] versus 27.3% [n = 383] at baseline, and 49% [n = 1023] versus 20.6% [n = 321] on day 3). Four hundred and fifty-eight (33%) patients clustered in the first group were clustered in the second group on day 3. In contrast, 638 (27%) patients clustered in the second group were clustered in the first group on day 3.Conclusions During the first days, patients can be clustered into two groups and the process of clustering patients may change as they continue to evolve. This means that despite a vast majority of patients remaining in the same cluster, a minority reaching 33% of patients analyzed may be re-categorized into different clusters based on their progress. Such changes can significantly impact their prognosis

    Prognostic implications of comorbidity patterns in critically ill COVID-19 patients: A multicenter, observational study

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    Background The clinical heterogeneity of COVID-19 suggests the existence of different phenotypes with prognostic implications. We aimed to analyze comorbidity patterns in critically ill COVID-19 patients and assess their impact on in-hospital outcomes, response to treatment and sequelae. Methods Multicenter prospective/retrospective observational study in intensive care units of 55 Spanish hospitals. 5866 PCR-confirmed COVID-19 patients had comorbidities recorded at hospital admission; clinical and biological parameters, in-hospital procedures and complications throughout the stay; and, clinical complications, persistent symptoms and sequelae at 3 and 6 months. Findings Latent class analysis identified 3 phenotypes using training and test subcohorts: low-morbidity (n=3385; 58%), younger and with few comorbidities; high-morbidity (n=2074; 35%), with high comorbid burden; and renal-morbidity (n=407; 7%), with chronic kidney disease (CKD), high comorbidity burden and the worst oxygenation profile. Renal-morbidity and high-morbidity had more in-hospital complications and higher mortality risk than low-morbidity (adjusted HR (95% CI): 1.57 (1.34-1.84) and 1.16 (1.05-1.28), respectively). Corticosteroids, but not tocilizumab, were associated with lower mortality risk (HR (95% CI) 0.76 (0.63-0.93)), especially in renal-morbidity and high-morbidity. Renal-morbidity and high-morbidity showed the worst lung function throughout the follow-up, with renal-morbidity having the highest risk of infectious complications (6%), emergency visits (29%) or hospital readmissions (14%) at 6 months (p<0.01). Interpretation Comorbidity-based phenotypes were identified and associated with different expression of in-hospital complications, mortality, treatment response, and sequelae, with CKD playing a major role. This could help clinicians in day-to-day decision making including the management of post-discharge COVID-19 sequelae. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd
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