48 research outputs found

    Hidrógeno puro a partir de biogás: efecto de la adición de agua en la etapa de reducción ("Steam Iron Process") utilizando óxidos de hierro y ferritas de cobalto como transportadores de oxígeno

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    En el presente proyecto se ha estudiado la producción de hidrógeno puro a partir de la combinación de los procesos de reformado seco de metano y “steam iron”. Se ha investigado este proceso usando dos sólidos transportadores de oxígeno, ferritas de cobalto y sólido “triple”. El reformado seco de metano permite la descomposición de un biogás sintético, en presencia de un catalizador de níquel, generando una corriente altamente reductora formada principalmente por H2 y CO. Este gas de síntesis reduce al transportador de oxígeno a un menor estado de oxidación. Posteriormente, se oxida con vapor de agua produciendo así hidrógeno de alta pureza. A este proceso cíclico se le conoce como “steam iron”. Uno de sus inconvenientes es la deposición de coque en las etapas de reducción, lo que provoca la obturación del lecho y la posible contaminación del H2 con óxidos de carbono en la oxidación. Ante este problema se ha propuesto la adición de pequeñas concentraciones de agua al biogás con el fin de solucionar dicho inconveniente operacional. Los diferentes ensayos han sido llevados a cabo en un reactor de lecho fijo analizándose los gases exhaustos del reactor por micro cromatografía. El estudio consiste en buscar la concentración de agua óptima que permita un compromiso entre producción de hidrógeno y cantidad de coque generado, dado que el carácter oxidante de la misma podría inhibir la etapa de reducción. Para ello se han testeado concentraciones desde el 0 – 12,5 % H2O manteniendo la temperatura en la reducción a 700 ºC y en la oxidación a 500 ºC. Por un lado, se ha llevado a cabo la búsqueda de la cantidad de agua idónea, y, por otro lado, se ha estudiado la estabilidad de los sólidos a lo largo de los ciclos redox para las mejores condiciones de operación. Previamente a los experimentos en el lecho fijo, se ha llevado a cabo un análisis termogravimétrico para ambos sólidos, así como su caracterización por medio de técnicas como: determinación de la superficie específica (BET), difractometría de rayos X (XRD) y microscopía electrónica de barrido (SEM). Estas dos últimas también se han realizado posteriormente, permitiendo comparar la diferencia entre el sólido fresco y tras tres ciclos de reacción. Finalmente se ha llevado a cabo una comparación de los resultados obtenidos con otros reportados en bibliografía de reformado de metano, con el fin de situar el proceso utilizado en el marco actual de producción de hidrógeno, así como con otros estudios llevados a cabo en el presente grupo de investigación, CREG

    Hidrógeno puro a partir de biogás: Efecto de la adición de agua en la etapa de reducción del proceso RSM+SIP con diferentes óxidos metálicos como transportadores de oxígeno

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    Se estudia experimentalmente, en reactor de lecho fijo, el efecto de adicionar agua en la etapa de reducción del proceso combinado RSM+SIP para obtener hidrógeno puro a partir de biogás. Se comprueba la viabilidad para los óxidos empleados, evitándose además la acumulación de coque y la consiguiente necesidad de regeneración

    Prevalence of post-intensive care syndrome in mechanically ventilated patients with COVID-19

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    Coronavirus disease 19 (COVID-19) patients usually require long periods of mechanical ventilation and sedation, which added to steroid therapy, favours a predisposition to the development of delirium and subsequent mental health disorders, as well as physical and respiratory sequelae. The aim of this study was to determine the prevalence of post-intensive care syndrome (PICS) at 3 months after hospital discharge, in a cohort of mechanically ventilated patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). An ambispective, observational study was conducted in three hospitals with intensive care unit (ICU) follow-up clinics. We studied adults who survived a critical illness due to SARS-CoV-2 infection requiring invasive mechanical ventilation. A physical (muscle strength and pulmonary function), functional [12-Item Short Form Health Survey (SF-12), and Barthel score], psychological [hospital anxiety and depression (HADS) and posttraumatic stress disorder symptom severity scales], and cognitive [Montreal cognitive assessment (MoCA) test] assessment were performed. A total of 186 patients were evaluated at 88 days (IQR 68–121) after hospital discharge. Mean age was 59 ± 12 years old, 126 (68%) patients were men, and median length of mechanical ventilation was 14 days (IQR 8–31). About 3 out of 4 patients (n = 139, 75%) met PICS criteria. Symptoms of cognitive and psychiatric disorders were found in 59 (32%) and 58 (31%) patients, respectively. Ninety-one (49%) patients had muscle weakness. Pulmonary function tests in patients with no respiratory comorbidities showed a normal pattern in 93 (50%) patients, and a restrictive disorder in 62 (33%) patients. Also, 69 patients (37%) were on sick leave, while 32 (17%) had resumed work at the time of assessment. In conclusion, survivors of critical illness due to SARS-CoV-2 infection requiring mechanical ventilation have a high prevalence of PICS. Physical domain is the most frequently damaged, followed by cognitive and psychiatric disorders. ICU follow-up clinics enable the assistance of this vulnerable populationThis study did not receive any funding or fnancial support. JMA and JV are funded by Grants from the Instituto de Salud Carlos III, Spain (CB06/06/1088, PI19/00141)

    Novel deep targeted sequencing method for minimal residual disease monitoring in acute myeloid leukemia

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    A high proportion of patients with acute myeloid leukemia who achieve minimal residual disease (MRD) negative status ultimately relapse because a fraction of pathological clones remains undetected by standard methods. We designed and validated a high-throughput sequencing method for MRD assessment of cell clonotypes with mutations of NPM1, IDH1/2 and/or FLT3-SNVs. For clinical validation, 106 follow-up samples from 63 patients in complete remission were studied by NGS, evaluating the level of mutations detected at diagnosis. The predictive value of MRD status by NGS, multiparameter flow cytometry, or quantitative PCR was determined by survival analysis. The method achieved a sensitivity of 10-4 for SNV mutations and 10-5 for insertions/deletions and could be used in acute myeloid leukemia patients who carry any mutation (86% in our diagnosis data set). NGS-determined MRD positive status was associated with lower disease-free survival (hazard ratio [HR] 3.4, p=0.005) and lower overall survival (HR 4.2, p<0.001). Multivariate analysis showed that MRD positive status by NGS was an independent factor associated with risk of death (HR 4.54, p =0.005) and the only independent factor conferring risk of relapse (HR 3.76, p =0.012). This NGS based method simplifies and standardizes MRD evaluation, with high applicability in acute myeloid leukemia. It also improves upon flow cytometry and quantitative PCR to predict acute myeloid leukemia outcome and could be incorporated in clinical settings and clinical trials.This study was supported by the Subdirección General de Investigación Sanitaria (Instituto de Salud Carlos III, Spain) grants PI13/02387 and PI16/01530, and the CRIS against Cancer foundation grant 2014/0120. M.L. holds a postdoctoral fellowship of the Spanish Ministry of Economy and Competitiveness (FPDI-2013-16409). P.R.P. holds a postdoctoral fellowship of the Spanish of Instituto de Salud Carlos III: Contrato Predoctoral de Formación en Investigación en Salud i-PFIS (IFI 14/00008).S

    Brain and immune system-derived extracellular vesicles mediate regulation of complement system, extracellular matrix remodeling, brain repair and antigen tolerance in Multiple sclerosis

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    Background: Multiple sclerosis (MS) is an immune-mediated central nervous system disease whose course is unpredictable. Finding biomarkers that help to better comprehend the disease's pathogenesis is crucial for supporting clinical decision-making. Blood extracellular vesicles (EVs) are membrane-bound particles secreted by all cell types that contain information on the disease's pathological processes. Purpose: To identify the immune and nervous system-derived EV profile from blood that could have a specific role as biomarker in MS and assess its possible correlation with disease state. Results: Higher levels of T cell-derived EVs and smaller size of neuron-derived EVs were associated with clinical relapse. The smaller size of the oligodendrocyte-derived EVs was related with motor and cognitive impairment. The proteomic analysis identified mannose-binding lectin serine protease 1 and complement factor H from immune system cell-derived EVs as autoimmune disease-associated proteins. We observed hepatocyte growth factor-like protein in EVs from T cells and inter-alpha-trypsin inhibitor heavy chain 2 from neurons as white matter injury-related proteins. In patients with MS, a specific protein profile was found in the EVs, higher levels of alpha-1-microglobulin and fibrinogen β chain, lower levels of C1S and gelsolin in the immune system-released vesicles, and Talin-1 overexpression in oligodendrocyte EVs. These specific MS-associated proteins, as well as myelin basic protein in oligodendrocyte EVs, correlated with disease activity in the patients with MS. Conclusion: Neural-derived and immune-derived EVs found in blood appear to be good specific biomarkers in MS for reflecting the disease state.This work was sponsored by a grant from Miguel Servet (CP20/00024 to Laura Otero-Ortega), Miguel Servet (CPII20/00002 to María Gutiérrez-Fernández), a predoctoral fellowship (FI18/00026 to Fernando Laso-García), a Río-Hortega grant (CM22/00065 to Gabriel Torres Iglesias and CM20/00047 to Elisa Alonso-López) and by Research Project (PI21/00918) from the Instituto de Salud Carlos III and co-funded by the European Union and by a grant CA1/RSUE/2021-00753 to Dolores Piniella funded by Ministerio de Universidades, Plan de Recuperación, Transformación y Resiliencia y la Universidad Autónoma de Madrid.S

    A Brucella melitensis H38ΔwbkF rough mutant protects against Brucella ovis in rams

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    Brucella melitensis and Brucella ovis are gram-negative pathogens of sheep that cause severe economic losses and, although B. ovis is non-zoonotic, B. melitensis is the main cause of human brucellosis. B. melitensis carries a smooth (S) lipopolysaccharide (LPS) with an N-formyl-perosamine O-polysaccharide (O-PS) that is absent in the rough LPS of B. ovis. Their control and eradication require vaccination, but B. melitensis Rev 1, the only vaccine available, triggers anti-O-PS antibodies that interfere in the S-brucellae serodiagnosis. Since eradication and serological surveillance of the zoonotic species are priorities, Rev 1 is banned once B. melitensis is eradicated or where it never existed, hampering B. ovis control and eradication. To develop a B. ovis specific vaccine, we investigated three Brucella live vaccine candidates lacking N-formyl-perosamine O-PS: Bov::CAΔwadB (CO2-independent B. ovis with truncated LPS core oligosaccharide); Rev1::wbdRΔwbkC (carrying N-acetylated O-PS); and H38ΔwbkF (B. melitensis rough mutant with intact LPS core). After confirming their attenuation and protection against B. ovis in mice, were tested in rams for efficacy. H38ΔwbkF yielded similar protection to Rev 1 against B. ovis but Bov::CAΔwadB and Rev1::wbdRΔwbkC conferred no or poor protection, respectively. All H38ΔwbkF vaccinated rams developed a protracted antibody response in ELISA and immunoprecipitation B. ovis diagnostic tests. In contrast, all remained negative in Rose Bengal and complement fixation tests used routinely for B. melitensis diagnosis, though some became positive in S-LPS ELISA owing to LPS core epitope reactivity. Thus, H38ΔwbkF is an interesting candidate for the immunoprophylaxis of B. ovis in B. melitensis-free areas.Publishe

    COVID-19 Severity and Survival over Time in Patients with Hematologic Malignancies: A Population-Based Registry Study

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    Mortality rates for COVID-19 have declined over time in the general population, but data in patients with hematologic malignancies are contradictory. We identified independent prognostic factors for COVID-19 severity and survival in unvaccinated patients with hematologic malignancies, compared mortality rates over time and versus non-cancer inpatients, and investigated post COVID-19 condition. Data were analyzed from 1166 consecutive, eligible patients with hematologic malignancies from the population-based HEMATO-MADRID registry, Spain, with COVID-19 prior to vaccination roll-out, stratified into early (February–June 2020; n = 769 (66%)) and later (July 2020–February 2021; n = 397 (34%)) cohorts. Propensity-score matched non-cancer patients were identified from the SEMI-COVID registry. A lower proportion of patients were hospitalized in the later waves (54.2%) compared to the earlier (88.6%), OR 0.15, 95%CI 0.11–0.20. The proportion of hospitalized patients admitted to the ICU was higher in the later cohort (103/215, 47.9%) compared with the early cohort (170/681, 25.0%, 2.77; 2.01–3.82). The reduced 30-day mortality between early and later cohorts of non-cancer inpatients (29.6% vs. 12.6%, OR 0.34; 0.22–0.53) was not paralleled in inpatients with hematologic malignancies (32.3% vs. 34.8%, OR 1.12; 0.81–1.5). Among evaluable patients, 27.3% had post COVID-19 condition. These findings will help inform evidence-based preventive and therapeutic strategies for patients with hematologic malignancies and COVID-19 diagnosis.Depto. de MedicinaFac. de MedicinaTRUEFundación Madrileña de Hematología y HemoterapiaFundación Leucemia y LinfomaAsociación Madrileña de Hematología y Hemoterapiapu

    Subsurface Geophysics and Geology (GEOFSU

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    [EN] The geophysics line at the IGME began in 1927 as a Geophysics Sectiondedicated to subsurface exploration. During all this time, it has been developed in order to support and give expert service in all IGME’s activities both as a geological service and public research institution, as well as a research and development work itself. On the other hand, in recent years the IGME has promoted a line of research aimed at the characterization and 3D modeling of geological structures and formations, the development of dedicated software and the evolution and sophistication of computer equipment. The new scenario of incorporation of the IGME to the CSIC as a national reference center in the field of Earth Sciences has allowed the establishment of the GEOFSUB Research Group (Subsurface Geophysics and Geology). It is constituted by 21 members who had been collaborating regularly of the IGME former scientific-technic areas Geophysics and remote sensing (Área de Geofísica y Teledetección) and Subsurface geology and 3D geological modelling (Área de Geología del Subsuelo y Modelización Geológica 3D). Our main differentiating element is our extensive knowledge of geophysical and geological techniques, which allows us to characterize the subsoil in an optimal waPeer reviewe
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