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International audience; Safe and effective vaccines against coronavirus disease 2019 (COVID-19) are essential for ending the ongoing pandemic. Although impressive progress has been made with several COVID-19 vaccines already approved, it is clear that those developed so far cannot meet the global vaccine demand alone. We describe a COVID-19 vaccine based on a replication-defective gorilla adenovirus expressing the stabilized prefusion severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein named GRAd-COV2. We assessed the safety and immunogenicity of a single-dose regimen of this vaccine in healthy younger and older adults to select the appropriate dose for each age group. For this purpose, a phase 1, dose-escalation, open-labeled trial was conducted including 90 healthy participants (45 aged 18 to 55 years old and 45 aged 65 to 85 years old) who received a single intramuscular administration of GRAd-COV2 at three escalating doses. Local and systemic adverse reactions were mostly mild or moderate and of short duration, and no serious adverse events were reported. Four weeks after vaccination, seroconversion to spike protein and receptor binding domain was achieved in 43 of 44 young volunteers and in 45 of 45 older participants. Consistently, neutralizing antibodies were detected in 42 of 44 younger-age and 45 of 45 older-age volunteers. In addition, GRAd-COV2 induced a robust and T helper 1 cell (T H 1)-skewed T cell response against the spike protein in 89 of 90 participants from both age groups. Overall, the safety and immunogenicity data from the phase 1 trial support the further development of this vaccine.

Safe and effective vaccines against coronavirus disease 2019 (COVID-19) are urgently needed to control the ongoing pandemic. Although impressive progress has been made with several COVID-19 vaccines already approved, it is clear that those developed so far cannot meet the global vaccine demand. We have developed a COVID-19 vaccine based on a replication-defective gorilla adenovirus expressing the stabilized pre-fusion SARS-CoV-2 Spike protein, named GRAd-COV2. We aimed to assess the safety and immunogenicity of a single-dose regimen of this vaccine in healthy younger and older adults to select the appropriate dose for each age group. To this purpose, a phase 1, dose-escalation, open-label trial was conducted including 90 healthy subjects, (45 aged 18-55 years and 45 aged 65-85 years), who received a single intramuscular administration of GRAd-CoV2 at three escalating doses. Local and systemic adverse reactions were mostly mild or moderate and of short duration, and no serious AE was reported. Four weeks after vaccination, seroconversion to Spike/RBD was achieved in 43/44 young volunteers and in 45/45 older subjects. Consistently, neutralizing antibodies were detected in 42/44 younger age and 45/45 older age volunteers. In addition, GRAd-COV2 induced a robust and Th1-skewed T cell response against the S antigen in 89/90 subjects from both age groups. Overall, the safety and immunogenicity data from the phase 1 trial support further development of this vaccine.One Sentence SummaryGRAd-COV2, a candidate vaccine for COVID-19 based on a novel gorilla adenovirus, is safe and immunogenic in younger and older adults

In this work, the thermal stability of two samples of Cu-11.8 wt%Al obtained by different milling processes is analyzed. Several TEM techniques were used and HT-XRD experiments performed to determine the crystal structure and the morphological microstructure of the samples obtained during different heat treatments. The heat treatments were: quenching from 850 °C to room temperature and two consecutive calorimetric runs at 5 °C/min. After the quenching,α2 is the major phase observed, reaching 95 mass%. The remaining 5 mass% consisted of martensitic phases: one sample had γ′, a hexagonal structure, and the other β1′, a rhombohedral structure. During the first calorimetric run, the sample containing the γ′ phase exhibited a calorimetric event and the sample containing the β1′ phase did not. The calorimetric event is attributed to the austenitic transformation γ′ → β1. The lack of calorimetric event in the sample containing the β1′ is associated with the inhibition of the transformation β1′ → β1 because of the precipitation of the γ2 phase. Finally, the absence of a calorimetric event in the second run with the first sample is associated with the retransformation to β1′ instead to γ′ phase during cooling of the first calorimetric run. These studies determined that the first sample is a better candidate than the second sample to produce a shape memory alloy after thermo-mechanical treatments of the milled powders. Fil: Sánchez Pascal, Nadia Soledad. Universidad Nacional de Cuyo. Facultad de Ingeniería; Argentina Fil: Giordana, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina Fil: Napolitano, Federico Ricardo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Esquivel, Marcelo Ricardo Oscar. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Universidad Nacional de Cuyo. Centro Regional Universitario Bariloche; Argentina Fil: Zelaya, Maria Eugenia. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina

Oxides with proton conductivity have a great potential for applications in environmental energy technology. Despite the BaCe0.4Zr0.4Y0.2O3−δ (BCZY) perovskites being well-known proton conductors, it is a challenge to determine the optimal operating temperature range where the energy applications benefit most from this unique property. The protonic transport properties strongly depend on crystal structure and local distortions in the participating cation coordination sphere, according to related temperatures and gas feed. The transport and crystallographic properties of BCZY were simultaneously studied by impedance spectroscopy (IS) and synchrotron X-ray diffraction (S-XRD). A strong correlation between conductivity and the lattice parameter, corresponding in principle to a cubic symmetry, was observed, mainly between 400 and 700 °C. The protonic conductivity range was analyzed by the H/D isotopic effect on the impedance spectra, which helped to identify protonic conduction as the governing transport mechanism below 600 °C, while the transport via oxygen vacancies dominates above this temperature. In order to assess the real crystallographic structure, the simultaneous refinement of laboratory XRD and neutron diffraction (ND) patterns was performed. According to this, BCZY changes from rhombohedral symmetry below 400 °C to cubic at 600 °C in a second-order phase transition. Complementary quasielastic neutron scattering (QENS) enables us to determine a protonic jump length of 3.1 Å, which matches the O–O distances in the octahedral oxygen coordination sphere around the cations. These results support the protonic self-diffusion through proton hopping between intraoctahedral O sites as the main transport mechanism up to 600 °C., This work was supported by Agencia Nacional de Promocion de Ciencia y Tecnologia (ANPCyT) PICT-2016-2965 and PICT2014-1849, CONICET PIP-2015-0565, LNLS (Brazil), under proposals 20150099 and 20170278, and ILL (France) under proposal 7-03-168. L. Giebeler is grateful to the German Federal Ministry of Education and Research (BMBF) and the Argentinian Ministry of Science and Technology (MinCyT) for funding in the bilateral project DeFLeST (01DN14002). J. A. Alonso thanks the Spanish Ministry for Science, Innovation and Universities for funding the Project MAT2017-84496-R.

UO2 nanoparticles doped with 4, 8, 10 and 15 wt% Gd2O3were synthesized by a reverse strike method. Crystal structure and chemical homogeneity were evaluated using a combination of X-ray diffraction and microscopy tools. An exhaustive study of the composition and its homogeneity at the micro and at the nanometer level was carried out in this nuclear fuel material. Field Emission Gun Scanning and Transmission Electron Microscopy images revealed the presence of micrometer scale agglomerates of nanoparticles, with rounded morphology and an average crystallite size of 100 nm. Rietveld refinements of high-statistic X-ray Diffraction data determined the crystal structure and composition. Furthermore, Energy Dispersive Spectroscopy using a 2 nm2 spot on the sample surface determined a Gd concentration variation around the average of ±5% in different spots of a single crystallite and of ±10% between different crystallites. However, when measuring large amounts of nanoparticles the concentration averages, producing a homogeneous composition distribution at the micrometer scale.

New LT-SOFC cathodes with La0.5-xPrxBa0.5CoO3-δ (0 ≤ x ≤ 0.5) compositions were studied. The La-rich compounds exhibit an inter-growing cubic and tetragonal structure whereas the Pr-rich show a tetragonal structure. Cathode polarization resistances, estimated from electrochemical impedance (EIS), take values around 0.15 and 0.04 Ω cm2 in air at 600 and 700 °C, respectively. The O2-reduction mechanism and its kinetic coefficients, O-ion diffusion (Dchem) and O-surface exchange (kchem), were studied by applying the ALS model for macro homogenous porous electrodes to the EIS data, in combination with microstructural parameters obtained from three-dimensional tomography using focused ion beam-scanning electron microscopy (3D FIB-SEM). The diffusion coefficients for samples with mixing of phases take values of Dchem ∼ 10-6 cm2 s-1, at 700 °C in air, whereas the pure tetragonal phases present lower values Dchem ∼ 10-8 cm2 s-1. On the contrary the kchem for all samples takes values ranging between 0.4 and 1 × 10-4 cm s-1 at 700 °C in air. In addition, the origin of time evolution of polarization at 700 °C in air was evaluated by combining the EIS spectra as a function of time and the ex situ sample characterization of fresh and tested samples by 3D FIB-SEM tomography and inductively coupled plasma-optical emission spectrometry (ICP-OES). Little changes of microstructures were detected, whereas an increasing of the amount of a water-soluble Ba surface species in comparison with total cation surface segregation was observed for all samples after the ageing. This may constitute the main reason causing the polarization resistance degradation. However, the analysis of time evolution shows, that contrary to the situations reported for SrO segregation in Sr-based perovskites, the Dchem is the coefficient mainly affected for compositions with inter-grown phases. At the same time, both Dchem and kchem decreases with time when only the tetragonal phase is present. Fil: Garcés, D.. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina Fil: Wang, H.. Northwestern University; Estados Unidos Fil: Barnett, S.A.. Northwestern University; Estados Unidos Fil: Leyva, Adelma Graciela. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Napolitano, Federico Ricardo. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina Fil: Fuentes, Rodolfo Oscar. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Troiani, Horacio Esteban. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina Fil: Mogni, Liliana Verónica. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina

In this work we studied the electrochemical performance of Ba0.5Sr0.5Fe0.8Cu0.2O3-δ (BSFCu) as cathode for Intermediate Temperature Solid Oxide Fuel Cells (IT-SOFC) with Ce0.9Gd0.1O1.95 (CGO) electrolyte and the effect of the symmetric cell preparation temperature on the oxygen reduction reaction (ORR) activity. Symmetrical cells with the configuration BSFCu/CGO/BSFCu were prepared at 900 °C, 950 °C and 1000 °C to perform the electrochemical characterization in the 500-700 °C temperature range. The resultant area specific resistance (ASR) of the cells with different preparation temperatures followed the tendency: ASR900°C < ASR950°C < ASR1000°C. The symmetric cell constructed at 900 °C showed ASR values of 0.18, 0.078 and 0.035 Ω cm2 at 600, 650 and 700 °C respectively, which demonstrated superior electrochemical activities than previous reports. Additional, X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM) techniques were used to characterize the microstructure of the original and fired BSFCu materials and correlate it with the cell preparation temperature. Fil: Vázquez, Santiago. Universidad de la Republica. Facultad de Química; Uruguay Fil: Basbus, Juan Felipe. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Soldati, Analía Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Napolitano, Federico Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Serquis, Adriana Cristina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Suescun, Leopoldo. Universidad de la Republica. Facultad de Química; Uruguay

In this work, a combined synchrotron X-ray diffraction (XPD), X-ray absorption near edge spectroscopy (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) study of La0.4Sr0.6Ti1-yCoyO3±δ (0 ≤ y ≤ 0.5), intended as symmetric solid oxide fuel cells electrode, is presented. Charge compensation mechanisms were characterized by room temperature measurements; LSTC has a perovskite pseudocubic structure with an A-site vacancy concentration related with Co doping level. This result seems to be triggered by the fact that Ti remains in a higher formal valence (around 4+) independent of the Co concentrations. On the contrary, Co K-edge XANES spectra show a dependency with the doping level but this seems to be related to structural changes. In-situ measurements simulating a symmetric SOFC working environment show that LSTC undergoes a rhombohedral to cubic perovskite phase transition with critical temperature dependent of the structural distortion level. Fil: Napolitano, Federico Ricardo. Comisión Nacional de Energía Atómica. Gerencia de Area de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Soldati, Analía Leticia. Comisión Nacional de Energía Atómica. Gerencia de Area de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Geck, Jochen. Leibniz Institute for Solid State and Materials Research IFW; Alemania Fil: Suescun, Leopoldo. Universidad de la Republica. Facultad de Química; Uruguay Fil: Acuña, Leandro Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Científicas y Técnicas de las Fuerzas Armadas. Centro de Investigaciones en Sólidos; Argentina Fil: Fernandez Zuvich, Afra. Comisión Nacional de Energía Atómica. Gerencia de Area de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina Fil: Lamas, Diego German. Universidad Nacional del Comahue. Facultad de Ingeniería; Argentina Fil: Serquis, Adriana Cristina. Comisión Nacional de Energía Atómica. Gerencia de Area de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada; Argentina

We present combined Synchrotron X-ray Absorption Near Edge Spectroscopy (XANES) andExtended X-ray Absorption Fine Structure (EXAFS) study of La0.4Sr0.6Ti1yCoyO3d(0 The measurements were performed at room temperature at the Ti and the Co K-edges inorder to determine the local structural and electronic changes around the two transitionmetals. We find that Ti remains in a higher formal valence (around 4þ) independent of theCo concentration. In contrast to this, dramatic and systematic changes are observed for theCo as a function of y.We conclude that the stability of the Ti4þ triggers the A-site deficiencyin our samples and predicts that oxygen vacancies are much more easily formed at largeCo content, which in turn will greatly enhance the performance as electrode material. Fil: Napolitano, Federico Ricardo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Soldati, Analía Leticia. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Geck, Jochen. Leibinz. Institute for Solid State and Materials Research; Alemania Fil: Lamas, Diego German. Universidad Nacional del Comahue; Argentina Fil: Serquis, Adriana Cristina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina

We present a crystallographic, morphologic and redox dynamic study on (60:40) NiO/Ce0.9Gd0.1O1.95 (NiO/GDC) cermets simulating Intermediate Temperature Solid Oxide Fuel Cells (IT-SOFC) anodes in situ conditions. We tested micro- and nanometer sized materials at 700ºC in three different atmospheres (5% H2, 5% O2 and 20% CH4). We used Dispersive X-ray Absorption Spectroscopy (DXAS) analysisat the Ce L3-edge and at the Ni K-edge to follow the metal´s oxidation states. A correlation between the catalytic/redox properties and the sample´s characteristics (microstructure, Ni distribution, etc.) was found, indicating that nanometric sized particles showed faster and higher reduction extents than micrometric particles of the same composition. Fil: Fernandez Zuvich, Afra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Larrondo, Susana Adelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Investigación y Desarrollo Estratégico para la Defensa. Ministerio de Defensa. Unidad de Investigación y Desarrollo Estratégico para la Defensa; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Química. Laboratorio de Procesos Catalíticos; Argentina Fil: Saleta, Martin. Laboratório Nacional de Luz Síncrotron; Brasil Fil: Napolitano, Federico Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Caneiro, Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Troiani, Horacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Lamas, Diego Germán. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Arce, Mauricio Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Serquis, Adriana Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Soldati, Analía Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina

Lanthanum strontium titanates based oxides, materials with perovskite-type crystal structure, are good candidates for symmetrical fuel cell electrodes. They can become good mixed conductors (electronic and ionic) and reach adequate electrocatalytic activity for both oxygen reduction and fuel oxidation reactions if the right doping or structural modification of the (La,Sr)TiO3 compound is performed. However, the crystallographic information reported in the literature indicates a noticeable lack of reproducibility, since it is strongly dependent on synthesis conditions. In this work, La0.4Sr0.6Ti1−yCoyO3+δ (0.0 ≤ y ≤ 0.5) synthesis by a low-temperature chemical route and its structural characterization by X-ray powder diffraction and transmission electron microscopy are reported. From Rietveld refinements results, charge compensation mechanisms are studied and their correlation with synthesis parameters is discussed. We show that the creation of Sr vacancies at the A-site of the perovskite-type structure is the main compensation mechanism and their concentration decreases with the incorporation of Co in the crystal structure.

IKBKG/NEMO gene mutations cause an X-linked, dominant neuroectodermal disorder named Incontinentia Pigmenti (IP). Located at Xq28, IKBKG/NEMO has a unique genomic organization, as it is part of a segmental duplication or low copy repeat (LCR1LCR2, 99 identical) containing the gene and its pseudogene copy (IKBKGP). In the opposite direction and outside LCR1, IKBKG/NEMO partially overlaps G6PD, whose mutations cause a common X-linked human enzymopathy. The two LCRs in the IKBKG/NEMO locus are able to recombine through non-allelic homologous recombination producing either a pathological recurrent exon 410 IKBKG/NEMO deletion (IKBKGdel) or benign small copy number variations. We here report that the local high frequency of micro/macro-homologies, tandem repeats and repeat/repetitive sequences make the IKBKG/NEMO locus susceptible to novel pathological IP alterations. Indeed, we describe the first two independent instances of inter-locus gene conversion, occurring between the two LCRs, that copies the IKBKGP pseudogene variants into the functional IKBKG/NEMO, causing the de novo occurrence of p.Glu390ArgfsX61 and the IKBKGdel mutations, respectively. Subsequently, by investigating a group of 20 molecularly unsolved IP subjects using a high-density quantitative polymerase chain reaction assay, we have identified seven unique de novo deletions varying from 4.8 to approximate to 115 kb in length. Each deletion removes partially or completely both IKBKG/NEMO and the overlapping G6PD, thereby uncovering the first deletions disrupting the G6PD gene which were found in patients with IP. Interestingly, the 4.8 kb deletion removes the conserved bidirectional promoterB, shared by the two overlapping IKBKG/NEMO and G6PD genes, leaving intact the alternative IKBKG/NEMO unidirectional promoterA. This promoter, although active in the keratinocytes of the basal dermal layer, is down-regulated during late differentiation. Genomic analysis at the breakpoint sites indicated that other mutational forces, such as non-homologous end joining, Alu-Alu-mediated recombination and replication-based events, might enhance the vulnerability of the IP locus to produce de novo pathological IP alleles.

We studied the electrochemical performance and microstructural characteristics of La0.5Sr0.5CoO3-d (LSCO) cathodes prepared by pulse laser deposition (PLD). This technique allows the growth of nanostructured cathode layers with vertically-aligned nanopores (VANP). In some samples, a vertically aligned nanocomposite (VAN) LSCO/CGO layer was introduced between the cathode and the Ce0.9Gd0.1O1.95 (CGO) electrolyte. The structure and morphology of several film configurations were characterized by X-ray diffraction, transmission and scanning electron microscopy, and synchrotron X-ray reflectometry, while the electrochemical properties were evaluated by means of impedance spectroscopy. We found that cathode area specific resistances (ASR) for VANP LSCO samples are almost independent of film thickness and are within the lowest reported values. A significant decrease in the ASR values was observed while heating the sample, but after this first heating, the ASR values were reproducible, indicating that these nanostructures are stable in the used temperatures and oxygen partial pressure ranges.

Human respiratory syncytial virus (HRSV) is a major cause of lower respiratory tract disease in children and the elderly for which there is still no effective vaccine. We have previously shown that PanAd3-RSV, which is a chimpanzee adenovirus-vectored vaccine candidate that expresses a secreted form of the HRSV F protein together with the N and M2-1 proteins of HRSV, is immunogenic in rodents and nonhuman primates, and protects mice and cotton rats from HRSV challenge. Because the extent to which protection demonstrated in rodent models will translate to humans is unclear, we have exploited the calf model of bovine RSV (BRSV) infection, which mimics HRSV disease in children more closely than do experimental models of unnatural laboratory hosts, to evaluate the safety and efficacy of the PanAd3-RSV vaccine. We show that PanAd3-RSV alone and in combination with a modified vaccinia Ankara expressing the same HRSV antigens (MVA-RSV) induced neutralizing antibodies and cellular immunity in young seronegative calves and protected against upper and lower respiratory tract infection and pulmonary disease induced by heterologous BRSV challenge. There was no evidence either of enhanced pulmonary pathology or of enhanced respiratory disease in vaccinated calves after BRSV challenge. These findings support the continued evaluation of the vectored RSV vaccines in man.

Nano-sized La0.4Sr0.6Co0.8Fe0.2O3−δ (LSCF) perovskite samples (prepared by a conventional acetate route and a novel acetate synthesis with HMTA additives), were tested simulating a red–ox cycle. The crystallography was studied by X-ray Powder Diffraction (XPD) and the changes in the oxidation state of the perovskite B-site were evaluated by synchrotron X-ray Absorption Near Edge Spectroscopy (XANES). After a reducing treatment, LSFC particles show the appearance of a new phase that coexists with the original one. The structural change is accompanied by a Co and Fe formal oxidation states decrease, although Fe remains always closer to 4+ and Co closer to 3+. The treatment produces a B-site valence average reduction from 3.52+ to 3.26+ and the formation of oxygen vacancies. A re-oxidation treatment under O2 rich atmosphere at 800 °C for 10 h shows that the change is reversible and independent of the two chemical methods used to synthesize the LSCF nano-particles. Fil: Soldati, Analía Leticia. Comision Nacional de Energia Atomica. Centro Atomico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Baque, Laura Cecilia. Comision Nacional de Energia Atomica. Centro Atomico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Napolitano, Federico Ricardo. Comision Nacional de Energia Atomica. Centro Atomico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Serquis, Adriana Cristina. Comision Nacional de Energia Atomica. Centro Atomico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The complexity of the process involved in the development of new technological devices requires the use of complementary characterization techniques in order to understand the whole phenomena. A usual approach to study materials for devices with non-ambient working conditions is to perform the experiment simulating the same environment (temperature, atmosphere, pressure, magnetic field, etc.). Although being a reasonable approach, this could fall short when real working conditions are more complex [1, 2]. Nowadays, the implementation of in-operando characterization techniques is a major field of capabilities development at world-wide large facilities [3-5] and, in lesser scale, at laboratory level [6]. The situation afore described is particularly applicable to the field of high temperature electrochemical devices such as Solid Oxide Fuel Cells (SOFC) and Solid Oxide Electrolyzer Cells (SOEC) where the different materials involved in the device are exposed to extreme environments and, moreover, could exists a strong correlation between different properties. For example, it is well known the dependence of the crystallographic parameters with several relevant electrochemical properties such as electrical conductivity, chemical compatibility, electrode reaction performance, etc [7, 8]. The simultaneous characterization of such properties in-operando condition allows gaining insight into some still not well understood phenomena. In this work, we present the simultaneous crystallographic and electrochemical characterization through X-ray Diffraction and Electrochemical Impedance Spectroscopy, respectively, of three different materials: a proton conductor electrolyte, an O2 electrode material, and a symmetrical (H2 and O2) electrode material. In order to study these materials we use a home-made sample holder specifically designed to study the electrical resistivity and the electrode polarization resistance evolution simultaneously with structural properties, under in-situ or in-operando conditions. Firstly, we followed a second order phase transition found on the proton conductor electrolyte material BaCe0.4Zr0.4Y0.2O3- δ at around 400°C under wet oxidizing and reducing atmospheres and its influence on its ionic conductivity. This phase transition (related to a crystallographic distortion coming from the hydration/dehydration process) affects the lattice parameters and, therefore, the ionic transport properties. The utilization of the in-operando sample holder allow us to get direct information about how this structural distortion affects the transport properties. Secondly, we studied the electrochemical performance of Nd2NiO4+ δ electrode material and its crystallographic parameters under an in-operando condition through the simultaneous EIS and XRD measurements of a half cell applying several electrode potentials. While their ionic conductivity combines the migration of interstitial oxygen (δ) in the rock-salt layer and the migration of oxygen vacancies in the perovskite layer, it is actually dominated by the former due to the higher mobility of these defects. Therefore, the O-content play a fundamental role in the O2 electrode activity (specially working under anodic polarization) and, moreover, is the driven force of a first order phase transition from an orthorhombic (Fmmm) to a tetragonal (I4/mmm) symmetry at 505 °C. Lastly, we also followed the second order phase transition exhibited by the symmetrical electrode La0.4Sr0.6Ti0.5Co0.5O3 at around 300 °C (in both oxidizing and reducing atmospheres), passing from a rhombohedral perovskite structure (R-3c) to the ideal cubic perovskite (Pm-3m) as temperature is increased. This phase transition is mediated by the rigid rotation of the oxygen octahedra (around a-a-a- direction, in Glazer’s notation) [9]. The correlation between the electrochemical properties and structural parameters on each system is discussed. 1. Zhang, C., et al., Nature Materials, 2010. 9(11): p. 944-949. 2. Kirtley, J.D., et al., Analytical Chemistry, 2012. 84(22): p. 9745-9753. 3. Peterson, V.K. and C.M. Papadakis, IUCrJ, 2015. 2(2): p. 292-304. 4. Gallo, E. and P. Glatzel, Advanced Materials, 2014. 26(46): p. 7730-7746. 5. Mueller, D.N., et al., Nature Communications, 2015. 6. 6. Brightman, E., et al., Review of Scientific Instruments, 2012. 83(5). 7. Imada, M., A. Fujimori, and Y. Tokura, Reviews of Modern Physics, 1998. 70(4 PART I): p. 1039-1263. 8. Fagg, D.P., et al., Solid State Ionics, 2003. 156(1-2): p. 45-57. 9. Napolitano, F., et al., ECS Transactions, 2013. 58(3): p. 185-193.

In this work we present and analysis of the influence of workshop activities performed in our city regarding the dissemination of crystallographic science in all educational levels. The organized workshops in honor of the IYCr are aimed to introduce crystallography to elementary and high schools teachers. The main goal is to improve teachers' knowledge in crystal formation and its techniques. This will allow teachers to elaborate laboratory projects that include crystallography principles according to their own students' level and to encourage the participation in the national and international crystal growing competition. Topics: 1. Introduction to crystallography 2. Atomic structure, chemical bonds and periodic table 3. Types of crystalline solids: metallic, ionic and covalent 4. Crystalline systems 5. Introduction to structure determination using X-ray diffraction 6. Crystal growing

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La1-xSrxCo1-yFeyO3-? oxides are good candidates for solid oxide fuel cell (SOFC) cathodes because these materials present high ionic and electronic conductivity, and compatibility with Cerium Gadolinium Oxide (CGO) electrolytes allowing a lower operation temperature. In this work, we report the synthesis of La0.4Sr0.6Co0.8Fe0.2O3-? (LSCF) nanotubes prepared by a porous polycarbonate membrane approach, obtaining different microstructures depending on sintering conditions. The structure and morphology of the nanotubes and deposited films were characterized by X-ray diffraction, transmission and scanning microscopy. Finally, we obtained nanostructured films of vertically aligned LSCF tubes deposited over the whole surface of CGO pellets with diameter up to 2.5cm in a direct and single step process.