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Solid oxide fuel cells (or SOFC) are a class of solid-state electrochemical conversion devices that produce electricity directly from oxidizing a fuel gas. They consist in an anode-cathode duet separated by a solid electrolyte, i.e. an oxide conducting material. The anode is fed with hydrogen or other fuels whereas the cathode is in contact with air, meaning oxygen. Overall, a SOFC operates thanks to the combined action of two external stimuli: a gaseous environment and temperature.Owing to the recent advances in in situ and operando transmission electron microscopy (TEM), we have set up an experiment to operate a SOFC inside an environmental TEM to identify how the device microstructure determines its electrical properties.An elementary anode-electrolyte-cathode sandwich was prepared by Focused Ion Beam (FIB), and mounted on a heating and biasing microelectromechanical (MEMS) based specimen holder (DENSsolutions) inserted a FEI Titan ETEM.Our sample is made as a standard SOFC: the cathode is based on strontium-doped lanthanum manganite (LSM), the electrolyte is yttria-stabilized zirconia (YSZ) and the anode is a NiO cermet; both electrodes were co-sintered with YSZ. NiO was first reduced to Ni, leaving pores in the structure due to the volume loss and hence enabling the penetration of the fuel to the triple phase junctions Ni/YSZ/porosity at the anode side. For practical reasons, we have used a single chamber configuration where the anode and cathode were exposed simultaneously to the oxidant and reducing gases. Thanks to a difference in the catalytic activity between the electrodes, O2 should reduce at the cathode, while H2 should oxidize at the anode, thus leading to a voltage difference between the two terminals and detected by the biasing system of the holder.The reduction of NiO was then first performed under a forming gas N2:H2 in the ratio 20:1 under 15 mbar up to 750°C (N2 was constantly used as a mixing vector gas for safety reasons due to the need of mixing O2 and H2 in the single-chamber configuration). The O2 to H2 ratio was then increased to trigger the operation of the cell. A small quantity of oxygen was introduced into the microscope up to about 16 mbar at 600°C, a temperature sufficient to promote the dissociation of O2 molecules in the ETEM.At this point, the variation of current was correlated to the evolution of the gas fuel composition and the anode microstructure. The latter was followed by conventional and high resolution imaging, diffraction work and EELS (Electron Energy-Loss Spectroscopy).The system was then cycled several times by decreasing and re-increasing the O2 concentration in the gas flow and correlations between microstructure, gas composition, and cell voltage were positively established, as it will be discussed at the conference. Results were further confirmed by macroscopic ex situ tests in an oven using the same materials [1].The operation of a SOFC in a single chamber configuration was demonstrated thanks to operando ETEM. Nevertheless, the pressure and flow limits with this instrument have restricted its operation to a transient working state. This operando experiment opens numerous perspectives to investigate possible failure pathways affecting SOFCs, like poisoning of active sites or coarsening of the Ni catalyst [2].[1] Q. Jeangros, M. Bugnet T. Epicier, C. Frantz, S. Diethelm, D. Montinaro, E. Tyukalova, G. Pivak, J. Van herle, A. Hessler-Wyser, M. Duchamp, under review (submitted 2021/10).[2] The authors acknowledge the French microscopy network METSA (www.metsa.fr) for funding and CLYM (Consortium Lyon-St-Etienne de Microscopie, www.clym.fr) for the ETEM access. The FIB preparation was performed at the Facilities for Analysis, Characterization, Testing and Simulations (FACTS, Nanyang Technological University NTU). Additional support was provided by the INSTANT project (France-Singapore MERLION program 2019-2020) and the start-up grant M4081924 at NTU.

Objectives: Limited cutaneous systemic sclerosis (LcSSc) is the most common subset of SSc but it has been overlooked in the past years. At a time at which clinical trials focus on diffuse cutaneous SSc (DcSSc) we aimed at clarifying the outcomes of LcSSc and at evaluating whether potential drug positioned in DcSSc may also be used in LcSSc. Methods: The EUSTAR database was used to investigate skin, lung and peripheral vasculopathy outcomes in LcSSc. Worsening of skin fibrosis, ILD and peripheral vasculopathy were defined by an increase in modified Rodnan skin score (mRSS) > 3.5 points, a decrease of FVC > 10% in patients with ILD at baseline, and by the development of new digital ulcers (DU) in patients without DU at baseline. Results: 8013 LcSSc and 4786 DcSSc patients were included. In contrast to DcSSc, skin disease was remarkably stable in the majority of LcSSc patients with >80% having a change lower than ±4 units of mRSS at 12, 24 and 36 months follow-up. Conversely, FVC changes over time were very similar between LcSSc and DcSSc. Regarding DU, numbers of patients with new DU over time seemed to be almost similar between the two subsets. Conclusions: LcSSc patients have a low mRSS at baseline with marginal changes with time. Conversely, SSc-ILD can be as progressive as in DcSSc supporting the inclusion of LcSSc patients in SSc-ILD trials and suggesting potential benefit of any anti-ILD drugs. Similarly, although slightly less common, DU should receive the same attention in the two subsets.

Energy behaviour is embedded within the physical and social contexts of daily life; the interplay between behaviour and its contextual influences can be thought of as an “energy culture”. Behaviour-based energy interventions aim to impact demand through influencing some aspect of energy culture - what people have, think, and/or do. Understanding how a program does (or doesn’t) work requires an understanding of changes in these elements of energy culture. This paper presents and tests a set of instruments that evaluate household energy culture before and after an intervention. Findings indicate that the proposed instruments are consistent with the conceptual variables they were designed to measure and have strong predictive validity. This work highlights the potential for reliable and valid methods to complement traditional measures of program effectiveness, providing deeper learning into how interventions lead to savings. Such insights can support program improvement, and ultimately increase the impact of behavioural interventions.

We analysed more than 600 red deer (Cervus elaphus) from large parts of its European distribution range at 13 microsatellite loci, presenting the first continent-wide study of this species using nuclear markers. Populations were clearly differentiated (overall FST = 0.166, Jost’s Dest = 0.385), and the BAPS clustering algorithm yielded mainly geographically limited and adjacent genetic units. When forced into only three genetic clusters our data set produced a very similar geographic pattern as previously found in mtDNA phylogeographic studies: a western group from Iberia to central and parts of Eastern Europe, an eastern group from the Balkans to Eastern Europe and a third group including the threatened relict populations from Sardinia and Mesola in Italy. This result was also confirmed by a multivariate approach to analysing our data set, a discriminant analysis of principal components (DAPC). Calculations of genetic diversity and effective population sizes (linkage-46 disequilibrium approach) yielded the lowest results for Italian (Sardinia, Mesola ; Ne between two and eight) and Scandinavian red deer, in line with known bottlenecks in these populations. Our study is the first to present comparative nuclear genetic data in red deer across Europe and may serve as a baseline for future analyses of genetic diversity and structuring in this widespread ungulate.