1,604 research outputs found

    Hydrogen evolution reaction at lead/carbon porous electrodes studied by a novel electrochemical mass spectrometry set-up

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    Lead–acid batteries are robust, low-cost, and have a large power-to-weight ratio. Recently, small amounts of carbon-based materials with a high surface area have been included in the Pb electrode as additives to improve the high-rate partial state of charge. However, carbon-based materials also enhance the hydrogen evolution reaction during the charging process at the negative active material (NAM), which is undesirable and dangerous. Therefore, in the current communication, a promising differential electrochemical mass spectrometry (DEMS) set-up suitable for studying the hydrogen evolution reaction (HER) at technical NAM electrodes in lead–acid batteries (LABs) is reported for the first time.Fil: Mondino, Tomas Miguel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: García, Gonzalo. Universidad de La Laguna; EspañaFil: Pastor, Elena. Universidad de La Laguna; EspañaFil: Fungo, Fernando Gabriel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; ArgentinaFil: Planes, Gabriel Angel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Tecnologías Energéticas y Materiales Avanzados; Argentin

    Experiences of spanish public administration in requirements management and acquisition management processes

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    This paper shows the main contributions of the 1st Symposium on Improvement Process Models and Software Quality of Public Administrations. The obtained results expose the need to promote the implementation of Software Maturity Models and show possible advantages of its application in software processes of Public Administrations. Specifically, it was analyzed the current status in two process areas: Requirements Management and Subcontracting Management

    Neuro-Sliding Control for Underwater ROV’s Subject to Unknown Disturbances

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    Proposed in this paper is a model-free and chattering-free second order sliding mode control(2nd-SMC) in combination with a backpropagation neural network (BP-NN) control scheme for underwater vehicles to deal with external disturbances (i.e., ocean currents) and parameter variations caused, for instance, by the continuous interchange of tools. The compound controller, here called the neuro-sliding control (NSC), takes advantage of the 2nd-SMC robustness and fast response to drive the position tracking error to zero. Simultaneously, the BP-NN contributes with its capability to estimate and to compensate online the hydrodynamic variations of the vehicle. When a change in the vehicle’s hydrodynamics occurs, the 2nd-SMC may no longer be able to compensate for the variations since its feedback gains are tuned for a di erent condition; thus, in order to preserve the desired performance, it is necessary to re-tune the feedback gains, which a cumbersome and time consuming task. To solve this, a viable choice is to implement a BP-NN control scheme along with the 2nd-SMC that adds or removes energy from the system according to the current condition it is in, in order to keep, or even improve, its performance. The e ectiveness of the proposed compound controller was supported by experiments carried out on a mini-ROV

    Long-term precipitation in Southwestern Europe reveals no clear trend attributable to anthropogenic forcing

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    We present a long-term assessment of precipitation trends in Southwestern Europe (1850-2018) using data from multiple sources, including observations, gridded datasets and global climate model experiments. Contrary to previous investigations based on shorter records, we demonstrate, using new long-term, quality controlled precipitation series, the lack of statistically significant long-term decreasing trends in precipitation for the region. Rather, significant trends were mostly found for shorter periods, highlighting the prevalence of interdecadal and interannual variability at these time-scales. Global climate model outputs from three CMIP experiments are evaluated for periods concurrent with observations. Both the CMIP3 and CMIP5 ensembles show precipitation decline, with only CMIP6 showing agreement with long term trends in observations. However, for both CMIP3 and CMIP5 large interannual and internal variability among ensemble members makes it difficult to identify a trend that is statistically different from observations. Across both observations and models, our results make it difficult to associate any declining trends in precipitation in Southwestern Europe to anthropogenic forcing at this stage.This work was supported by the research projects CGL2017-82216-R, CGL2017-83866-C3-3-R and PCI2019-103631, financed by the Spanish Commission of Science and Technology and FEDER; CROSSDRO project financed by the AXIS (Assessment of Cross(X) - sectoral climate Impacts and pathways for Sustainable transformation), JPI-Climate co-funded call of the European Commission and INDECIS which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant 690462)

    A high-resolution spatial assessment of the impacts of drought variability on vegetation activity in Spain from 1981 to 2015

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    59 Pags.- 12 Tabls.- 35 Figs. © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License.Drought is a major driver of vegetation activity in Spain, with significant impacts on crop yield, forest growth, and the occurrence of forest fires. Nonetheless, the sensitivity of vegetation to drought conditions differs largely amongst vegetation types and climates. We used a high-resolution (1.1 km) spatial dataset of the normalized difference vegetation index (NDVI) for the whole of Spain spanning the period from 1981 to 2015, combined with a dataset of the standardized precipitation evapotranspiration index (SPEI) to assess the sensitivity of vegetation types to drought across Spain. Specifically, this study explores the drought timescales at which vegetation activity shows its highest response to drought severity at different moments of the year. Results demonstrate that – over large areas of Spain – vegetation activity is controlled largely by the interannual variability of drought. More than 90 % of the land areas exhibited statistically significant positive correlations between the NDVI and the SPEI during dry summers (JJA). Nevertheless, there are some considerable spatio-temporal variations, which can be linked to differences in land cover and aridity conditions. In comparison to other climatic regions across Spain, results indicate that vegetation types located in arid regions showed the strongest response to drought. Importantly, this study stresses that the timescale at which drought is assessed is a dominant factor in understanding the different responses of vegetation activity to drought.This research has been supported by the Spanish Commission of Science and Technology and FEDER (grant no. PCIN-2015-220), the Spanish Commission of Science and Technology and FEDER (grant no. CGL2014-52135-C03-01), the Spanish Commission of Science and Technology and FEDER (grant no. CGL2017-83866-C3-3-R), the Spanish Commission of Science and Technology and FEDER (grant no. CGL2017-82216-R), WaterWorks 2014 (grant no. 690462, IMDROFLOOD), the JPI Climate (grant no. 690462, INDECIS), and WaterWorks 2015 (FORWARD grant).Peer reviewe

    Long-term variability and trends in meteorological droughts in Western Europe (1851-2018)

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    We analyzed long-term variability and trends in meteorological droughts across Western Europe using the Standardized Precipitation Index (SPI). Precipitation data from 199 stations spanning the period 1851-2018 were employed, following homogenisation, to derive SPI-3 and SPI-12 series for each station, together with indices on drought duration and severity. Results reveal a general absence of statistically significant long-term trends in the study domain, with the exception of significant trends at some stations, generally covering short periods. The largest decreasing trends in SPI-3 (i.e. increasing drought conditions) were found for summer in the British and Irish Isles. In general, drought episodes experienced in the last two or three decades have precedents during the last 170 years, emphasising the importance of long records for assessing change. The main characteristic of drought variability in Western Europe is its strong spatial diversity, with regions exhibiting a homogeneous temporal evolution. Notably, the temporal variability of drought in Western Europe is more dominant than long-term trends. This suggests that long-term drought trends cannot be confirmed in Western Europe using precipitation records alone. This study provides a long-term regional assessment of drought variability in Western Europe, which can contribute to better understanding of regional climate change during the past two centuries.This work was supported by the research projects PCIN-2015-220 and CGL2017- 82216-R financed by the Spanish Commission of Science and Technology and FEDER, IMDROFLOOD financed by the WaterWorks 2014 co-funded call of the European Commission, CROSSDRO financed by the AXIS (Assessment of Cross(X) – sectorial climate Impacts and pathways for Sustainable transformation) JPI-Climate co-funded call of the European Commission, INDECIS, which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR), FCT (PT) with co-funding by the European Union (Grant 690462), Irish Research Council COALESCE grant 2019/43

    Late gadolinium enhancement distribution patterns in non-ischemic dilated cardiomyopathy: Genotype-phenotype correlation.

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    AIMS Late gadolinium enhancement (LGE) is frequently found in patients with dilated cardiomyopathy (DCM), there is little information about its frequency and distribution pattern according to underlying genetic substrate. We sought to describe LGE patterns according to genotype and to analyze the risk of major ventricular arrhythmias (MVA) according to patterns. METHODS AND RESULTS Cardiac magnetic resonance findings and LGE distribution according to genetics was performed in a cohort of 600 DCM patients followed at 20 Spanish centers. After exclusion of individuals with multiple causative gene variants or with variants in infrequent DCM-causing genes, 577 patients (34% females, mean age 53.5 years, LVEF 36.9 ± 13.9%) conformed the final cohort. A causative genetic variant was identified in 219 (38%) patients and 147 (25.5%) had LGE. Significant differences were found comparing LGE patterns between genes (P < 0.001). LGE was absent or rare in patients with variants in TNNT2, RBM20 and MYH7 (0%, 5% and 20%, respectively). Patients with variants in DMD, DSP and FLNC showed predominance of LGE subepicardial pattern (50%, 41% and 18%, respectively) whereas patients with variants in TTN, BAG3, LMNA and MYBPC3 showed unspecific LGE patterns. Genetic yield differed according to LGE pattern. Patients with subepicardial, lineal midwall, transmural, right ventricular insertion points or with combination of LGE patterns showed increased risk of MVA compared with patients without LGE. CONCLUSION LGE patterns in DCM has a specific distribution according to the affected gene. Certain LGE patterns are associated with increased risk of MVA and with increased yield of genetic testing.This study has been funded by Instituto Salud Carlos III (ISCIII) through the projects ‘PI18/0004, PI19/01283, and PI20/0320’ (co-funded by the European Regional Development Fund/European Social Fund ‘A way to make Europe’/‘Investing in your future’). The Hospital Universitario Puerta de Hierro, the Hospital Universitario Vall Hebrón, the Hospital General Universitario Gregorio Marañón, and the Hospital Universitario Virgen de la Arrixaca are members of the European Reference Network for Rare, Low Prevalence, and Complex Diseases of the Heart (ERN GUARD-Heart). F.d.F. receives grant support from ISCIII (CM20/00101). R.B. receives funding from the Obra Social la Caixa Foundation. M.B. receives funding from ISCIII (PI19/01283). The CNIC is supported by the ISCIII, Ministerio de Ciencia e Innovación of the Spanish Government (MCIN), and Pro CNIC Foundation.S

    Penetrance of Dilated Cardiomyopathy in Genotype-Positive Relatives

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    BACKGROUND Disease penetrance in genotype -positive (G+) relatives of families with dilated cardiomyopathy (DCM) and the characteristics associated with DCM onset in these individuals are unknown. OBJECTIVES This study sought to determine the penetrance of new DCM diagnosis in G+ relatives and to identify factors associated with DCM development. METHODS The authors evaluated 779 G+ patients (age 35.8 +/- 17.3 years; 459 [59%] females; 367 [47%] with variants in TTN ) without DCM followed at 25 Spanish centers. RESULTS After a median follow-up of 37.1 months (Q1 -Q3: 16.3-63.8 months), 85 individuals (10.9%) developed DCM (incidence rate of 2.9 per 100 person -years; 95% CI: 2.3-3.5 per 100 person -years). DCM penetrance and age at DCM onset was different according to underlying gene group (log -rank P = 0.015 and P <0.01, respectively). In a multivariable model excluding CMR parameters, independent predictors of DCM development were: older age (HR per 1 -year increase: 1.02; 95% CI: 1.0-1.04), an abnormal electrocardiogram (HR: 2.13; 95% CI: 1.38-3.29); presence of variants in motor sarcomeric genes (HR: 1.92; 95% CI: 1.05-3.50); lower left ventricular ejection fraction (HR per 1% increase: 0.86; 95% CI: 0.82-0.90) and larger left ventricular end -diastolic diameter (HR per 1 -mm increase: 1.10; 95% CI: 1.06-1.13). Multivariable analysis in individuals with cardiac magnetic resonance and late gadolinium enhancement assessment (n = 360, 45%) identi fied late gadolinium enhancement as an additional independent predictor of DCM development (HR: 2.52; 95% CI: 1.43-4.45). CONCLUSIONS Following a first negative screening, approximately 11% of G+ relatives developed DCM during a median follow-up of 3 years. Older age, an abnormal electrocardiogram, lower left ventricular ejection fraction, increased left ventricular end -diastolic diameter, motor sarcomeric genetic variants, and late gadolinium enhancement are associated with a higher risk of developing DCM. (J Am Coll Cardiol 2024;83:1640 -1651) (c) 2024 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
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