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Nuclear forward scattering (NFS) is a synchrotron-based technique relying on the recoil-free nuclear resonance effect similar to Mössbauer spectroscopy. In this work, we introduce NFS for in situ and operando measurements during electrocatalytic reactions. The technique enables faster data acquisition and better discrimination of certain iron sites in comparison to Mössbauer spectroscopy. It is directly accessible at various synchrotrons to a broad community of researchers and is applicable to multiple metal isotopes. We demonstrate the power of this technique with the hydrogen evolution mechanism of an immobilized iron porphyrin supported on carbon. Such catalysts are often considered as model systems for iron-nitrogen-carbon (FeNC) catalysts. Using in situ and operando NFS in combination with theoretical predictions of spectroscopic data enables the identification of the intermediate that is formed prior to the rate-determining step. The conclusions on the reaction mechanism can be used for future optimization of immobilized molecular catalysts and metal-nitrogen-carbon (MNC) catalysts.
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For a future hydrogen economy, non-precious metal catalysts for the water splitting reactions are needed that can be implemented on a global scale. Metal-nitrogen-carbon (MNC) catalysts with active sites constituting a metal center with fourfold coordination of nitrogen (MN4 ) show promising performance, but an optimization rooted in structure-property relationships has been hampered by their low structural definition. Porphyrin model complexes are studied to transfer insights from well-defined molecules to MNC systems. This work combines experiment and theory to evaluate the influence of porphyrin substituents on the electronic and electrocatalytic properties of MN4 centers with respect to the hydrogen evolution reaction (HER) in aqueous electrolyte. We found that the choice of substituent affects their utilization on the carbon support and their electrocatalytic performance. We propose an HER mechanism for supported iron porphyrin complexes involving a [FeII (Pâ )]- radical anion intermediate, in which a porphinic nitrogen atom acts as an internal base. While this work focuses on the HER, the limited influence of a simultaneous interaction with the support and an aqueous electrolyte will likely be transferrable to other catalytic applications.
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Inspired by photosystem II (PS II), Mn oxide based electrocatalysts have been repeatedly investigated as catalysts for the electrochemical oxygen evolution reaction (OER), the anodic reaction in water electrolysis. However, a comparison of the conditions in biological OER catalysed by the water splitting complex CaMn4Ox with the requirements for an electrocatalyst for industrially relevant applications reveals fundamental differences. Thus, a systematic development of artificial Mn-based OER catalysts requires both a fundamental understanding of the catalytic mechanisms as well as an evaluation of the practicality of the system for industrial scale applications. Experimentally, both aspects can be approached using in situ and operando methods including spectroscopy. This paper highlights some of the major challenges common to different operando investigation methods and recent insights gained with them. To this end, vibrational spectroscopy, especially Raman spectroscopy, absorption techniques in the bandgap region and operando X-ray spectroelectrochemistry (SEC), both in the hard and soft X-ray regime are particularly focused on here. Technical challenges specific to each method are discussed first, followed by challenges that are specific to Mn oxide based systems. Finally, recent in situ and operando studies are reviewed. This analysis shows that despite the technical and Mn specific challenges, three specific key features are common to most of the studied systems with significant OER activity: structural disorder, Mn oxidation states between III and IV, and the appearance of layered birnessite phases in the active regime.
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BACKGROUND: In December 2019, the new virus infection coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged. Simple clinical risk scores may improve the management of COVID-19 patients. Therefore, the aim of this pilot study was to evaluate the quick Sequential Organ Failure Assessment (qSOFA) score, which is well established for other diseases, as an early risk assessment tool predicting a severe course of COVID-19. METHODS: We retrospectively analyzed data from adult COVID-19 patients hospitalized between March and July 2020. A critical disease progress was defined as admission to intensive care unit (ICU) or death. RESULTS: Of 64 COVID-19 patients, 33% (21/64) had a critical disease progression from which 13 patients had to be transferred to ICU. The COVID-19-associated mortality rate was 20%, increasing to 39% after ICU admission. All patients without a critical progress had a qSOFA scoreâ¯≤ 1 at admission. Patients with a critical progress had in only 14% (3/21) and in 20% (3/15) of cases a qSOFA scoreâ¯≥ 2 at admission (pâ¯= 0.023) or when measured directly before critical progression, respectively, while 95% (20/21) of patients with critical progress had an impairment oxygen saturation (SO2) at admission time requiring oxygen supplementation. CONCLUSION: A low qSOFA score cannot be used to assume short-term stable or noncritical disease status in COVID-19.
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COVID-19 , Sepsis , Adulto , COVID-19/diagnóstico , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Puntuaciones en la Disfunción de Órganos , Proyectos Piloto , Pronóstico , Estudios Retrospectivos , SARS-CoV-2RESUMEN
PURPOSE: To evaluate the association of peripheral blood (PBL) and broncho-alveolar lavage (BAL) biomarkers with inflammatory versus fibrotic high-resolution computed tomography (HRCT) findings in interstitial lung disease (ILD) patients. METHODS: HRCT findings of 127 consecutive ILD-board patients were semi-quantitatively evaluated: reticulation/honeycombing (RET), traction bronchiectasis (TBR) and emphysema (EMP) were classified as non-inflammatory/fibrotic; consolidations (CON), ground glass opacities (GGO), parenchymal nodules (NDL) and mosaic attenuation (MOS) as active inflammatory. Each HRCT finding was assessed in six distinct lung regions, resulting scores were graded as minimal (0-1 regions involved), medium (2-4) or extensive (5-6). Associations of routinely assessed PBL/BAL biomarkers with these HRCT scores were evaluated using Spearman correlation coefficients and graphical presentation; significance was tested by applying Kruskal-Wallis tests. RESULTS: Blood neutrophil, lymphocyte and eosinophil fraction, neutrophil to lymphocyte ratio (NLR) and BAL lymphocyte fraction consistently showed opposite correlations with inflammatory versus non-inflammatory/fibrotic HRCT finding scores. Blood lymphocyte fraction significantly differed by graded GGO (p = 0.032) and CON (p = 0.027) extent, eosinophil fraction by TBR (p = 0.006) and NLR by CON (p = 0.009). C-reactive protein was significantly related to GGO (p = 0.023) and CON (p = 0.004), BAL lymphocyte fraction to GGO (p = 0.017) extent. CONCLUSION: Blood lymphocyte and eosinophil fraction, NLR, CRP and BAL lymphocyte fraction may aid to differentiate inflammatory from non-inflammatory/fibrotic ILD patterns. TRIAL REGISTRATION: This evaluation was based on data from the ILD registry of Kepler University Hospital Linz, as approved by the ethics committee of the Federal State of Upper-Austria (EK Number. I-26-17).
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Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/metabolismo , Recuento de Células Sanguíneas , Líquido del Lavado Bronquioalveolar/citología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
Functional impairment caused by chronic obstructive pulmonary disease (COPD) impacts on activities of daily living and quality of life. Indeed, patients' submaximal exercise capacity is of crucial importance. It was the aim of this study to investigate the effects of an exercise training intervention with and without supplemental oxygen on submaximal exercise performance. This is a secondary analysis of a randomized, controlled, double-blind, crossover trial. 29 COPD patients (63.5 ± 5.9 years; FEV1 46.4 ± 8.6%) completed two consecutive 6-week periods of high-intensity interval cycling and strength training, which was performed three times/week with either supplemental oxygen or medical air (10 L/min). Submaximal exercise capacity as well as the cardiocirculatory, ventilatory, and metabolic response were evaluated at isotime (point of termination in the shortest cardiopulmonary exercise test), at physical work capacity at 110 bpm of heart rate (PWC 110), at the anaerobic threshold (AT), and at the lactate-2 mmol/L threshold. After 12 weeks of exercise training, patients improved in exercise tolerance, shown by decreased cardiocirculatory (heart rate, blood pressure) and metabolic (respiratory exchange ratio, lactate) effort at isotime; ventilatory response was not affected. Submaximal exercise capacity was improved at PWC 110, AT and the lactate-2 mmol/L threshold, respectively. Although supplemental oxygen seems to affect patients' work rate at AT and the lactate-2 mmol/L threshold, no other significant effects were found. The improved submaximal exercise capacity and tolerance might counteract patients' functional impairment. Although cardiovascular and metabolic training adaptations were shown, ventilatory efficiency remained essentially unchanged. The impact of supplemental oxygen seems less important on submaximal training effects.
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Terapia por Ejercicio/métodos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/terapia , Respiración Artificial , Actividades Cotidianas , Anciano , Presión Sanguínea , Estudios Cruzados , Método Doble Ciego , Tolerancia al Ejercicio , Femenino , Frecuencia Cardíaca , Entrenamiento de Intervalos de Alta Intensidad , Humanos , Ácido Láctico/sangre , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Estudios Prospectivos , Intercambio Gaseoso Pulmonar , Entrenamiento de FuerzaRESUMEN
BACKGROUND: Short-term, indoor exposure to environmental tobacco smoke (ETS) is still highly prevalent; however, little is known about the acute lung response in adult asthma. OBJECTIVES: We investigated whether acute, experimental ETS exposure influences symptoms, lung function, and inflammatory parameters. METHODS: Human subjects with asthma (n = 23) were exposed for 180 min to either room air or ETS at 250, 450, or 850 µg/m3. Respiratory symptoms, lung function, and exhaled nitric oxide (FeNO) were measured. Additionally, blood samples were analyzed for pro- and anti-inflammatory cytokines. RESULTS: Humans with asthma demonstrate an increase in respiratory symptoms at all levels of ETS exposure, while the forced expiratory volume in 1 s (FEV1) and FeNO decrease with increasing ETS. The anti-inflammatory cytokine interleukin (IL)-10 increases at intermediate ETS concentrations, whereas tumor necrosis factor (TNF)-α and IL-8 increase only at the highest ETS concentration. CONCLUSION: Following 180 min of acute, experimental ETS exposure, we observed a significant increase in respiratory symptoms, a decrease in lung function, and an increase in inflammatory cytokines, indicating an acute lung response in asthma.
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The aim was to evaluate the impact of multiple high-resolution computed tomography (HRCT) features on pulmonary function test (PFT) biomarkers in fibrotic interstitial lung disease (FILD) patients. HRCT of subsequently ILD-board-discussed FILD patients were semi-quantitatively evaluated in a standardized approach: 18 distinct lung regions were scored for noduli, reticulation, honeycombing, consolidations, ground glass opacities (GGO), traction bronchiectasis (BRK) and emphysema. Total lung capacity (TLC), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC, diffusion capacity for carbon monoxide (DLCO) and transfer coefficient (KCO) were assessed. Interactions between each PFT biomarker and all HRCT scores were visualized by network analyses, modeled according to the Schwarz Bayesian Information Criterion and incorporated in uni- and multivariate stepwise regression analyses. Among 108 FILD patients (mean age 67 years, 77% male), BRK extent was a major significant uni- or multivariate determinant of all PFT analyzed. Besides that, diffusion-based variables DLCO and KCO showed a larger dependency on reticulation, emphysema and GGO, while forced expiratory volume-based measures FEV1, FVC and FEV1/FVC were more closely associated with consolidations. For TLC, the only significant multivariate determinant was reticulation. In conclusion, PFT biomarkers derived from spirometry, body plethysmography and diffusion capacity in FILD patients are differentially influenced by semi-quantified HRCT findings.
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Enfermedades Pulmonares Intersticiales , Anciano , Teorema de Bayes , Femenino , Humanos , Pulmón/diagnóstico por imagen , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Masculino , Pruebas de Función Respiratoria , Tomografía Computarizada por Rayos X , Capacidad VitalRESUMEN
The use of low-temperature solution synthesis followed by a brief annealing step allows metastable single-phase Co3B nanoparticles to be obtained, with sizes ranging from 11 to 22 nm. The particles are ferromagnetic with a saturation magnetization of 91 A m2 kg-1 (corresponding to 1.02 µB/Co) and a coercive field of 0.14 T at 5 K, retaining the semihard magnetic properties of bulk Co3B. They display a magnetic blocking temperature of 695 K and a Curie temperature near 710 K, but the measurement of these high-temperature properties was complicated by decomposition of the particles during heating in the magnetometer. Additionally, the nanoparticles of Co3B were investigated as an electrocatalyst in the oxygen evolution reaction and showed a low onset potential of 1.55 V vs RHE. XPS measurements were performed before and after the electrocatalytic measurements to study the surface of the catalyst, to pinpoint what appear to be the active surface species.
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The CODEX index was developed and validated in patients hospitalized for COPD exacerbation to predict the risk of death and readmission within one year after discharge. Our study aimed to validate the CODEX index in a large external population of COPD patients with variable durations of follow-up. Additionally, we aimed to recalculate the thresholds of the CODEX index using the cutoffs of variables previously suggested in the 3CIA study (mCODEX). Individual data on 2,755 patients included in the COPD Cohorts Collaborative International Assessment Plus (3CIA+) were explored. A further two cohorts (ESMI AND EGARPOC-2) were added. To validate the CODEX index, the relationship between mortality and the CODEX index was assessed using cumulative/dynamic ROC curves at different follow-up periods, ranging from 3 months up to 10 years. Calibration was performed using univariate and multivariate Cox proportional hazard models and Hosmer-Lemeshow test. A total of 3,321 (87.8% males) patients were included with a mean ± SD age of 66.9 ± 10.5 years, and a median follow-up of 1,064 days (IQR 25-75% 426-1643), totaling 11,190 person-years. The CODEX index was statistically associated with mortality in the short- (≤3 months), medium- (≤1 year) and long-term (10 years), with an area under the curve of 0.72, 0.70 and 0.76, respectively. The mCODEX index performed better in the medium-term (<1 year) than the original CODEX, and similarly in the long-term. In conclusion, CODEX and mCODEX index are good predictors of mortality in patients with COPD, regardless of disease severity or duration of follow-up.
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Progresión de la Enfermedad , Disnea/etiología , Enfermedades Pulmonares Obstructivas/mortalidad , Enfermedades Pulmonares Obstructivas/fisiopatología , Anciano , Área Bajo la Curva , Calibración , Estudios de Cohortes , Comorbilidad , Femenino , Estudios de Seguimiento , Volumen Espiratorio Forzado , Humanos , Enfermedades Pulmonares Obstructivas/complicaciones , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Curva ROC , Medición de Riesgo/métodos , Brote de los Síntomas , Factores de TiempoRESUMEN
BACKGROUND: External validations and comparisons of prognostic models or scores are a prerequisite for their use in routine clinical care but are lacking in most medical fields including chronic obstructive pulmonary disease (COPD). Our aim was to externally validate and concurrently compare prognostic scores for 3-year all-cause mortality in mostly multimorbid patients with COPD. METHODS: We relied on 24 cohort studies of the COPD Cohorts Collaborative International Assessment consortium, corresponding to primary, secondary, and tertiary care in Europe, the Americas, and Japan. These studies include globally 15,762 patients with COPD (1871 deaths and 42,203 person years of follow-up). We used network meta-analysis adapted to multiple score comparison (MSC), following a frequentist two-stage approach; thus, we were able to compare all scores in a single analytical framework accounting for correlations among scores within cohorts. We assessed transitivity, heterogeneity, and inconsistency and provided a performance ranking of the prognostic scores. RESULTS: Depending on data availability, between two and nine prognostic scores could be calculated for each cohort. The BODE score (body mass index, airflow obstruction, dyspnea, and exercise capacity) had a median area under the curve (AUC) of 0.679 [1st quartile-3rd quartile = 0.655-0.733] across cohorts. The ADO score (age, dyspnea, and airflow obstruction) showed the best performance for predicting mortality (difference AUCADO - AUCBODE = 0.015 [95% confidence interval (CI) = -0.002 to 0.032]; p = 0.08) followed by the updated BODE (AUCBODE updated - AUCBODE = 0.008 [95% CI = -0.005 to +0.022]; p = 0.23). The assumption of transitivity was not violated. Heterogeneity across direct comparisons was small, and we did not identify any local or global inconsistency. CONCLUSIONS: Our analyses showed best discriminatory performance for the ADO and updated BODE scores in patients with COPD. A limitation to be addressed in future studies is the extension of MSC network meta-analysis to measures of calibration. MSC network meta-analysis can be applied to prognostic scores in any medical field to identify the best scores, possibly paving the way for stratified medicine, public health, and research.
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Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Índice de Severidad de la EnfermedadRESUMEN
High-resolution surface-sensitive synchrotron radiation photoelectron spectroscopy was used to study the interaction of water with the p-GaInP2(100) surface covered with submonolayer residual native oxide in order to get insight into water dissociation at the solar water-splitting photocathodes in real liquid environment. In the surface-sensitive valence band spectra features related to Ga-OH, In-OH, and H-In-OH bonds appear after emersion of the p-GaInP2(100) surface from liquid water at room temperature. Indium core levels remain intact after emersion, while the gallium core levels indicate transformation of gallium oxides to hydroxides, as well as the accumulation of metallic gallium. Surface sensitive P 2p core level spectra indicate formation of P-H bonds after emersion. These changes of the surface chemical bonds can be attributed to the dissociation of the water molecules on the p-GaInP2(100) surface, leading to the subsequent transformation of surface oxides to hydroxides. Interaction of water with the p-GaInP2(100) surface covered with submonolayer residual native oxide causes an increase in the work function by 80 meV and a modification of the valence band edge spectrum, which is evidence of a change of the surface dipole due to the charge redistribution induced by the transformation of the surface oxides to hydroxides.
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BACKGROUND: COPD is a treatable disease with increasing prevalence worldwide. Treatment aims to stop disease progression, to improve quality of life, and to reduce exacerbations. We aimed to evaluate the association of the stage of COPD on adherence to inhaled therapy and the relationship between adherence and COPD exacerbations. METHODS: A retrospective analysis of patients hospitalized for acute exacerbation of COPD in a tertiary care hospital in Upper Austria and discharged with a guideline conform inhaled therapy was performed. Follow-up data on medical utilization was recorded for the subsequent 24 months. Adherence to inhaled therapy was defined according to the percentage of prescribed inhalers dispensed to the patient and classified as complete (> 80%), partial (50-80%) or low (< 50%). RESULTS: Out of 357 patients, 65.8% were male with a mean age of 66.5 years and a mean FEV1 of 55.0%pred. Overall, 35.3% were current smokers, and only 3.9% were never-smokers. In 77.0% inhaled triple therapy (LAMA + LABA + ICS) was prescribed. 33.6% showed complete adherence to their therapy (33.2% in men, 34.4% in women), with a mean age of 67.0 years. Mean medication possession ratio by GOLD spirometry class I - IV were 0.486, 0.534, 0.609 and 0.755, respectively (p = 0.002). Hence, subjects with complete adherence to therapy had a significantly lower FEV1 compared to those with low adherence (49.2%pred. vs 59.2%pred., respectively; p < 0.001). The risk of exacerbations leading to hospitalization was 10-fold higher in GOLD spirometry class IV compared to GOLD spirometry class I, which was even more evident in multivariate analysis (OR 13.62). CONCLUSION: Complete adherence to inhaled therapy was only seen in 33.6% and was higher among those with more severe COPD. TRIAL REGISTRATION: Not applicable.
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Progresión de la Enfermedad , Cumplimiento de la Medicación/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Terapia Respiratoria , Anciano , Austria/epidemiología , Quimioterapia Combinada , Femenino , Volumen Espiratorio Forzado , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Nebulizadores y Vaporizadores , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Calidad de Vida , Estudios RetrospectivosRESUMEN
The scalable synthesis of phase-pure crystalline manganese nitride (Mn3 N2 ) from a molecular precursor is reported. It acts as a superiorly active and durable electrocatalyst in the oxygen evolution reaction (OER) from water under alkaline conditions. While electrophoretically deposited Mn3 N2 on fluorine tin oxide (FTO) requires an overpotential of 390â mV, the latter is substantially decreased to merely 270â mV on nickel foam (NF) at a current density of 10â mA cm-2 with a durability of weeks. The high performance of this material is due to the rapid transformation of manganese sites at the surface of Mn3 N2 into an amorphous active MnOx overlayer under operation conditions intimately connected with metallic Mn3 N2 , which increases the charge transfer from the active catalyst surface to the electrode substrates and thus outperforms the electrocatalytic activity in comparison to solely MnOx -based OER catalysts.
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This study aimed to identify simple rules for allocating chronic obstructive pulmonary disease (COPD) patients to clinical phenotypes identified by cluster analyses.Data from 2409 COPD patients of French/Belgian COPD cohorts were analysed using cluster analysis resulting in the identification of subgroups, for which clinical relevance was determined by comparing 3-year all-cause mortality. Classification and regression trees (CARTs) were used to develop an algorithm for allocating patients to these subgroups. This algorithm was tested in 3651 patients from the COPD Cohorts Collaborative International Assessment (3CIA) initiative.Cluster analysis identified five subgroups of COPD patients with different clinical characteristics (especially regarding severity of respiratory disease and the presence of cardiovascular comorbidities and diabetes). The CART-based algorithm indicated that the variables relevant for patient grouping differed markedly between patients with isolated respiratory disease (FEV1, dyspnoea grade) and those with multi-morbidity (dyspnoea grade, age, FEV1 and body mass index). Application of this algorithm to the 3CIA cohorts confirmed that it identified subgroups of patients with different clinical characteristics, mortality rates (median, from 4% to 27%) and age at death (median, from 68 to 76â years).A simple algorithm, integrating respiratory characteristics and comorbidities, allowed the identification of clinically relevant COPD phenotypes.
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Algoritmos , Enfermedad Pulmonar Obstructiva Crónica/clasificación , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Anciano , Anciano de 80 o más Años , Bélgica/epidemiología , Índice de Masa Corporal , Análisis por Conglomerados , Estudios de Cohortes , Comorbilidad , Femenino , Volumen Espiratorio Forzado , Francia/epidemiología , Humanos , Cooperación Internacional , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Fenotipo , Índice de Severidad de la Enfermedad , Factores de TiempoRESUMEN
BACKGROUND: COPD prevalence is highly variable and geographical altitude has been linked to it, yet with conflicting results. We aimed to investigate this association, considering well known risk factors. METHODS: A pooled analysis of individual data from the PREPOCOL-PLATINO-BOLD-EPI-SCAN studies was used to disentangle the population effect of geographical altitude on COPD prevalence. Post-bronchodilator FEV1/FVC below the lower limit of normal defined airflow limitation consistent with COPD. High altitude was defined as >1500 m above sea level. Undiagnosed COPD was considered when participants had airflow limitation but did not report a prior diagnosis of COPD. RESULTS: Among 30,874 participants aged 56.1 ± 11.3 years from 44 sites worldwide, 55.8% were women, 49.6% never-smokers, and 12.9% (3978 subjects) were residing above 1500 m. COPD prevalence was significantly lower in participants living at high altitude with a prevalence of 8.5% compared to 9.9%, respectively (p < 0.005). However, known risk factors were significantly less frequent at high altitude. Hence, in the adjusted multivariate analysis, altitude itself had no significant influence on COPD prevalence. Living at high altitude, however, was associated with a significantly increased risk of undiagnosed COPD. Furthermore, subjects with airflow limitation living at high altitude reported significantly less respiratory symptoms compared to subjects residing at lower altitude. CONCLUSION: Living at high altitude is not associated with a difference in COPD prevalence after accounting for individual risk factors. However, high altitude itself was associated with an increased risk of undiagnosed COPD.
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Altitud , Volumen Espiratorio Forzado/fisiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Encuestas y Cuestionarios , Anciano , Colombia/epidemiología , Femenino , Humanos , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Distribución Aleatoria , España/epidemiología , Espirometría/métodosRESUMEN
Studies report high in-hospital and post-discharge mortality of chronic obstructive pulmonary disease (COPD) exacerbations varying depending upon patient characteristics, hospital resources and treatment standards. This study aimed to investigate the patient, resource and organisational factors associated with in-hospital and 90-day post-discharge mortality and readmission of COPD exacerbations within the European COPD Audit. The audit collected data of COPD exacerbation admissions from 13 European countries.On admission, only 49.7% of COPD patients had spirometry results available and only 81.6% had blood gases taken. Using logistic regression analysis, the risk associated with in-hospital and post-discharge mortality was higher age, presence of acidotic respiratory failure, subsequent need for ventilatory support and presence of comorbidity. In addition, the 90-day risk of COPD readmission was associated with previous admissions. Only the number of respiratory specialists per 1000 beds, a variable related to hospital resources, decreased the risk of post-discharge mortality.The European COPD Audit identifies risk factors associated with in-hospital and post-discharge mortality and COPD readmission. Addressing the deficiencies in acute COPD care such as making spirometry available and measuring blood gases and providing noninvasive ventilation more regularly would provide opportunities to improve COPD outcomes.
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Auditoría Clínica , Mortalidad Hospitalaria , Readmisión del Paciente/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de los Gases de la Sangre/estadística & datos numéricos , Comorbilidad , Progresión de la Enfermedad , Europa (Continente)/epidemiología , Femenino , Recursos en Salud , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Mortalidad , Ventilación no Invasiva/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/terapia , Factores de Riesgo , Índice de Severidad de la Enfermedad , Espirometría/estadística & datos numéricosRESUMEN
To achieve an overall efficient solar water splitting device, not only the efficiencies of photo-converter and catalyst are decisive, but also their appropriate coupling must be considered. In this report we explore the origin of a voltage loss occurring at the interface between a thin film amorphous silicon tandem cell and the TiO2 corrosion protection layer by means of XPS. We find that the overall device can be disassembled into its primary constituents and that they can be analyzed separately, giving insight into the device structure as a whole. Thus, a series of model experiments were conducted, each representing a part of the complete device. We finally arrive at the conclusion, that the formation of a SiO2 interfacial layer between the TiO2 protection layer and the silicon cell gives rise to the voltage loss observed for the whole device.
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To reduce energy losses in water electrolysers a fundamental understanding of the water oxidation reaction steps is necessary to design efficient oxygen evolution catalysts. Here we present CoOx/Ti electrocatalytic films deposited by thermal and plasma enhanced chemical vapor deposition (CVD) onto titanium substrates. We report electrochemical (EC), photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) measurements. The electrochemical behavior of the samples was correlated with the chemical and electronic structure by recording XPS spectra before and after each electrochemical treatment (conditioning and cyclovoltammetry). The results show that the electrochemical behavior of CoOx/Ti strongly depends on the resulting electronic structure and composition. The thermal deposition leads to the formation of a pure Co(II)Ox which transforms to a mixed Co(II)Co(III)Ox during the OER. This change in oxidation state is coupled with a decrease in overpotential from η = 0.57 V to η = 0.43 V at 5 mA cm(-2). Plasma deposition in oxygen leads to a Co(III)-dominated mixed CoOx, that has a lower onset potential as deposited due to a higher Co(III) content in the initial deposited material. After the OER XPS results of the CoOx/Ti indicate a partial formation of hydroxides and oxyhydroxides on the oxide surface. Finally the plasma deposition in air, results in a CoOxOH2 surface, that is able to completely oxidizes during OER to an oxyhydroxide Co(III)OOH. With the in situ formed CoOOH we present a highly active catalyst for the OER (η = 0.34 at 5 mA cm(-2); η = 0.37 V at 10 mA cm(-2)).
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Nutritional status has been associated with clinical outcome in chronic airflow limitation (CAL), but epidemiological studies are scarce. We aimed to assess the relationship between body mass index (BMI) and CAL, taking into account confounding factors. 18,606 participants (49% male, 21% smokers, mean age: 55.8 ± 11.2 years, mean BMI: 26.7 ± 5.5 kg/m(2)) of the BOLD initiative from 26 sites in 23 countries were included. CAL was defined as post-bronchodilator forced expiratory volume in the first second/forced vital capacity < lower limit of normal. Low and obese BMI were defined as <21 kg/m(2) and ≥30 kg/m(2), respectively. Multivariate logistic regression analysis controlled for confounders age, sex and smoking, and meta-analysis of between-site heterogeneity and clustering. Prevalence of low and obese BMI, smoking history and prevalence of CAL were highly variable between sites. After adjustment for confounders, the meta-analysis of all sites showed that compared to subjects without CAL, low BMI was more frequent, (adjusted odds ratio (OR): 2.23 (95% confidence interval: 1.75, 2.85)) and conversely, obesity was less frequent in subjects with CAL (adjusted OR: 0.78 (0.65, 0.94)). In a worldwide population sample, CAL was associated with lower BMI, even after adjusting for confounding factors age, gender, smoking and between-site heterogeneity. These results indicate a CAL-specific association with body composition.