68 research outputs found
Platinum: A key element in electrode composition for reversible chloralkaline electrochemical cells
In this work, the performance of a reversible electrochemical cell using three different electrodes (Ti/Ru0.5Ir0.5O2, Ti/Ru0.3Ti0.7O2, and Ti/Ru0.3Ti0.6O2Pt0.1) is evaluated and compared for the oxidation of chlorides and reduction of chlorine. Results indicate that this technology is successful and that its efficiency depends significantly on the composition of the electrode in charge of the chlorine electrochemistry. Operating at 0.5 V allows us to obtain near 7 mA cm−2 and power efficiencies around 120 Wh mmol−1 hydrogen supplied. In electrolytic mode, efficiencies around 4 mol Cl2 mWh−1 can be obtained. The best performance is shown by the Ti/Ru0.3Ti0.6O2Pt0.1 electrode resulting from its roughest morphology and the presence of Pt. In shifting from electrolyzer to fuel cell mode, the current produced is rapidly stabilized for Ti/Ru0.3Ti0.6O2Pt0.1 and Ti/Ru0.5Ir0.5O2 electrodes. However, the electrode Ti/Ru0.5Ir0.5O2 showed a progressive change, which suggests a change in its composition that negatively affects the system.En este trabajo se evalúa y compara el desempeño de una celda electroquímica reversible utilizando tres electrodos diferentes (Ti/Ru 0.5 Ir 0.5 O 2 , Ti/Ru 0.3 Ti 0.7 O 2 , y Ti/Ru 0.3 Ti 0.6 O 2 Pt 0.1 ). para la oxidación de cloruros y reducción de cloro. Los resultados indican que esta tecnología es exitosa y que su eficiencia depende significativamente de la composición del electrodo a cargo de la electroquímica del cloro . Operando a 0,5 V nos permite obtener cerca de 7 mA cm −2y eficiencias energéticas de alrededor de 120 Wh mmol- 1 de hidrógeno suministrado. En modo electrolítico se pueden obtener eficiencias en torno a 4 mol Cl 2 mWh− 1 . El electrodo Ti/Ru 0.3 Ti 0.6 O 2 Pt 0.1 presenta el mejor comportamiento debido a su morfología más rugosa ya la presencia de Pt. Al pasar del modo electrolizador al modo de pila de combustible, la corriente producida se estabiliza rápidamente para los electrodos Ti/Ru 0,3 Ti 0,6 O 2 Pt 0,1 y Ti/Ru 0,5 Ir 0,5 O 2 . Sin embargo, el electrodo Ti/Ru0.5 Ir 0.5 O 2 mostró un cambio progresivo, lo que sugiere un cambio en su composición que afecta negativamente al sistema
Comparison of seven prognostic tools to identify low-risk pulmonary embolism in patients aged <50 years
publishersversionPeer reviewe
Association Between Preexisting Versus Newly Identified Atrial Fibrillation and Outcomes of Patients With Acute Pulmonary Embolism
Background Atrial fibrillation (AF) may exist before or occur early in the course of pulmonary embolism (PE). We determined the PE outcomes based on the presence and timing of AF. Methods and Results Using the data from a multicenter PE registry, we identified 3 groups: (1) those with preexisting AF, (2) patients with new AF within 2 days from acute PE (incident AF), and (3) patients without AF. We assessed the 90-day and 1-year risk of mortality and stroke in patients with AF, compared with those without AF (reference group). Among 16 497 patients with PE, 792 had preexisting AF. These patients had increased odds of 90-day all-cause (odds ratio [OR], 2.81; 95% CI, 2.33-3.38) and PE-related mortality (OR, 2.38; 95% CI, 1.37-4.14) and increased 1-year hazard for ischemic stroke (hazard ratio, 5.48; 95% CI, 3.10-9.69) compared with those without AF. After multivariable adjustment, preexisting AF was associated with significantly increased odds of all-cause mortality (OR, 1.91; 95% CI, 1.57-2.32) but not PE-related mortality (OR, 1.50; 95% CI, 0.85-2.66). Among 16 497 patients with PE, 445 developed new incident AF within 2 days of acute PE. Incident AF was associated with increased odds of 90-day all-cause (OR, 2.28; 95% CI, 1.75-2.97) and PE-related (OR, 3.64; 95% CI, 2.01-6.59) mortality but not stroke. Findings were similar in multivariable analyses. Conclusions In patients with acute symptomatic PE, both preexisting AF and incident AF predict adverse clinical outcomes. The type of adverse outcomes may differ depending on the timing of AF onset.info:eu-repo/semantics/publishedVersio
Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study
Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation
Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study
Summary
Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally.
Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies
have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of
the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income
countries globally, and identified factors associated with mortality.
Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to
hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis,
exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a
minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical
status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary
intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause,
in-hospital mortality for all conditions combined and each condition individually, stratified by country income status.
We did a complete case analysis.
Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital
diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal
malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome
countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male.
Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3).
Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income
countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups).
Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome
countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries;
p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients
combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11],
p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20
[1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention
(ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety
checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed
(ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of
parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65
[0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality.
Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome,
middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will
be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger
than 5 years by 2030
Respuestas fiscales del gobierno y de la economía real a las crisis: Estabilizadores automáticos versus estabilización automática
This paper looks at the discretionary fi scal and real economy support measures introduced by EMU Member States in response to the crises. The analyses build on a data base assembled by the Commission on individual crises response measures with a view to survey the implementation of the European Economic Recovery Programme (EERP). The paper first provides a broad overview of the types of crises-related measures taken, including broad estimates of their budgetary dimension. On this basis it appears that on an aggregate level, the discretionary support has been in line with agreed principles of being timely, temporary and targeted. Member States with restricted fi scal space has overall taken a more restrictive stance than those with more room of manoeuvre. The paper then looks at how these discretionary measures complement the "automatic" budget tabilisation. It appears that, in budgetary terms, about half of the discretionary measures add to the areas already covered by automatic stabilisers while the other half address other areas such as investments, industrial sectors and vulnerable groups particularly hit by the crises. The overall experience may suggest that it has been helpful with agreed ex-ante principles for how discretionary stimuli should be provided and that the provision of discretionary stimulus under such conditionality can work to strengthen the budgetary stabilisation capacity in a flexible way.Este artículo analiza las medidas discrecionales fi scales y de apoyo a la economía real introducidas por los países miembros de Unión Monetaria Europea en respuesta a la crisis. El análisis se realiza en base a datos recolectados por la Comisión Europea sobre medidas tomadas por cada país en respuesta a la crisis para evaluar la implementación del Programa de Recuperación Económica Europea. El artículo provee una extensa revisión de los tipos de medidas tomadas relacionadas con la crisis, incluyendo estimaciones de su dimensión presupuestaria. Con respecto a esto se encuentra que, a nivel agregado, el apoyo discrecional ha estado en línea con los principios aceptados de ser oportuno, transitorio y selectivo. Los Estados Miembros con capacidad fi scal más limitada en general han adoptado una postura más restrictiva que los que tienen más margen de maniobra. En el documento se analiza cómo estas medidas discrecionales complementan la estabilización presupuestaria "automática". Se encuentra que, en términos presupuestarios, cerca de la mitad de las medidas discrecionales apoyan a áreas ya cubiertas por los estabilizadores automáticos, mientras que la otra mitad apoya otras áreas como inversiones, sectores industriales y grupos vulnerables particularmente afectados por la crisis. La experiencia en general puede sugerir que los estímulos discrecionales han sido de gran ayuda y han estado de acuerdo con los principios preestablecidos de cómo deben ser provistos y que la implementación de este tipo políticas discrecionales pueden fortalecer la capacidad de estabilización presupuestaria de una manera flexible
EDZ investigations by ultrasonic borehole logging in drifts of different ages excavated in argillaceous formations of the tournemire experimental station (Aveyron, France)
Tracing interactions between natural argillites and hyper-alkaline fluids from engineered cement paste and concrete: Chemical and isotopic monitoring of a 15-years old deep-disposal analogue
International audienceSamples of Toarcian argillite were collected both next to and far from a CEM II cement paste and a CEM II concrete, within the specific context of a 15-a old borehole located in the Tournemire Experimental Platform (Aveyron, France). The objectives were evaluation of the mineralogical and geochemical changes of the claystone at the contact with the cementitious materials and determination of the spatial extent of the interactions. The approach includes the examination of the mineralogical (XRD, SEM, TEM), chemical (major, trace, rare earth elements) and isotopic (Sr, C, O) compositions of argillite whole-rocks and of various soluble phases, at two scales: in the rock matrix (P1 scale) and along micro-cracks (P2 scale). The two study scales outline nearly similar mineralogical modifications, shown by the presence of Ca silicate hydrates (C–S–H) and newly-formed CaCO3 within 10–15 mm of the cement paste and concrete. Chemical data from whole-rock argillites indicate few changes in a slightly thicker zone (18–20 mm), mainly consisting of an increase in the CaO wt.%, and a decrease in Sr contents. The other elementary contents remained quite constant except for MgO, which suggests redistribution with precipitation of a Mg-rich mineral phase at 20 mm from cement paste/concrete interface. Acetic acid leachates had more pronounced variations, including a decrease of the total elementary content in the same ‘geochemical disturbed zone’ (GDZ), together with a significant increase of the Sr isotopic ratios. A combination of Sr and C/O isotopic patterns was used to distinguish the behavior of secondary cementitious phases in the clay-rich rock: (i) calcite dissolution and re-precipitation is supported by C/O isotopic data and (ii) C–S–H neoformation is evidenced by the 87Sr/86Sr ratios; this tool also contributes to determine the origin of the fluids. The proportion of newly-formed C–S–H in the matrix and in the micro-cracks of the argillite is modeled
In situ investigations and reactive transport modelling of cement paste / argillite interactions in a saturated context and outside an excavated disturbed zone
International audienceThe interactions between cementitious materials and a clayey deep formation were investigated by studying the specific in situ context of the Tournemire Underground Research Laboratory (URL) of the French Institute for Radioprotection and Nuclear Safety and by reactive transport modelling using the HYTEC code. The study forms part of the safety assessment framework for the deep geological disposal of high to intermediate level long-lived radioactive waste. The in situ context investigated in the Tournemire URL corresponds to an engineered cemented borehole crosscutting the Toarcian argillite formation. The argillite/CEM II cement paste contacts have been in place over 18 a and were sampled in a saturated context outside the excavated disturbed zone (EDZ). Studies of the mineralogy (XRD, carbonatometry, SEM and TEM), petrophysical properties (BET) and geochemistry (TOC, Sr contents, C, O and Sr isotopes, EDS analyses) were carried out both on the argillite and on the cement paste in contact. Alteration of the cement paste is clearly expressed by decalcification and the opening of macroporosity. These modifications are mainly due to the dissolution of portlandite. The neoformation of C-S-H phases was identified in the first few micrometre next to the argillite interface, along with secondary carbonates at the outermost contact. Geochemical measurements argue for the introduction of a sedimentary fluid into the macroporosity of the cement paste to explain the formation of part of these secondary phases. This hypothesis is considered and tested using the HYTEC code, which indicates that such transport could have occurred near the argillite/cement paste contact at a very early stage. After this stage, the transport was reversed and 'cementitious' fluids flowed from the cement paste to the argillite. The changes brought about by these fluids are observed over a thickness of 11-13 mm in a so-called 'black rim', in which carbonates and C-S-H secondary phases are identified in the matrix of the sediment. An illitization process may also be observed in this altered rim, reaching its maximum development towards the inner part. Geochemical analyses show that the argillite disturbances are strictly confined to the black rim. Theoretical mineralogical profiles based on thermodynamic equilibria defined by the HYTEC code are in good agreement with the observations, and are used to achieve a better understanding of transport processes
Caractérisation de l'EDZ par méthodes sismiques et ultrasoniques
National audienceDifferent methods are used to characterize the seismic wave velocities and the spatial extent of the EDZ (Excavation Damaged Zone) around underground works. This study presents a synthesis of results obtained in two galleries of the IRSN Tournemire experimental stationDifférentes méthodes sont mises en oeuvre pour caractériser les vitesses des ondes sismiques et l'étendue de l'EDZ (Excavation Damaged Zone) autour des ouvrages souterrains. Ce travail présente une synthèse de résultats obtenus dans deux galeries de la station expérimentale IRSN de Tournemir
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