Preparation and Characterization of Anodes for Intermediate Temperature Solid Oxide Fuel Cells

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An exploration of familial associations of two movement pattern-derived subgroups of chronic disabling low back pain; a cross-sectional cohort study

© 2016 Elsevier Ltd. Background: Altered movement patterns with pain have been demonstrated in children, adolescents and adults with chronic disabling low back pain (CDLBP). A previously developed classification system has identified different subgroups including active extension and multidirectional patterns in patients with CDLBP. While familial associations have been identified for certain spinal postures in standing, it is unknown whether a familial relationship might exist between movement pattern-derived subgroups in families with CDLBP. Objectives: This study explored whether familial associations in movement pattern-derived subgroups within and between members of families with CDLBP existed. Design: Cross-sectional cohort study. Method: 33 parents and 28 children with CDLBP were classified into two subgroups based on clinical analysis of video footage of postures and functional movements, combined with aggravating factors obtained from Oswestry Disability Questionnaire. Prevalence of subgroups within family members was determined, associations between parent and child's subgroup membership was evaluated using Fisher's exact test, and spearman's correlation coefficient was used to determine the strength of association between familial dyads. Results: The majority of parents were classified as active extenders, sons predominately multidirectional and daughters were evenly distributed between the two subgroups. No significant association was found when comparing subgroups in nine parent-child relationships. Conclusions: The exploration of a small cohort of family dyads in this study demonstrated that children's movement pattern-derived subgroups could not be explained by their parents' subgroup membership. These results cannot be generalised to the CLBP population due to this study's small sample. Larger sample studies are needed to further elucidate this issue

Phase structure and thermal evolution in coating films and powders obtained by sol-gel process : Part II. ZrO2–2.5 mole% Y2O3

Powders and coatings of zirconia doped with 2.5 mole % yttria have been produced via the sol-gel route. The phase structure and subsequent thermal evolution in heating and cooling cycles have been investigated using mainly perturbed angular correlations spectroscopy. Thermal analyses and XRD as a function of temperature have also been performed to obtain complementary information. Upon heating, the amorphous gels crystallized into the tetragonal structure and showed the same hyperfine pattern and thermal behavior as observed in tetragonal zirconia obtained by the ceramic route: the two configurations of vacancies around zirconium ions denoted as t1 and t2 forms and their mutual t1 → t2 transformation. While the powder sample exhibited an incipient thermal instability above 1000 °C and underwent completely the t2 form to m–ZrO2 transition during subsequent, gradual cooling below 500 °C, the coating retained the tetragonal phase within the whole temperature range investigated. Hyperfine results suggest that the tetragonal phase stabilization is favored by the highly defective nature of the t1 form and consequently hardened by the availability of oxygen. The PAC derived activation energy for the fast diffusion of the oxygen vacancies inherent to the t2 form was determined as 0.54 ± 0.14 eV.Facultad de Ciencias Exacta

Influencia de parámetros de síntesis sobre las características de los polvos cerámicos nanométricos del compuesto SrXBa1-XNb2O6 (SBN)

En este trabajo se exponen los resultados del proceso de obtención de polvos cerámicos nanométricos del sistema Sr1-xBaxNb2O6 (SBN), para dos valores de x (0.33 y 0.50) que se encuentran dentro del rango para el cual el sistema tiene estructura tetragonal bronce de tungsteno y propiedad ferroeléctrica. Fueron comparados dos métodos de obtención (Pechini y coprecipitación controlada) variando parámetros de síntesis tales como pH de solución, precursor de niobio y tratamiento térmico. Los polvos obtenidos fueron caracterizados estructuralmente por medio de difracción de rayos X y morfológicamente por medio de microscopía electrónica de barrido. A partir del análisis de los resultados se concluyó sobre el efecto de los métodos de síntesis y de los parámetros mencionados, en la obtención de la fase pura y en tamaño de las partículas. El método Pechini (con pH igual a 9.7) permitió obtener la fase pura de SBN para x=0.33 y tamaño de partícula del orden de los 50 nm, mientras que con el método coprecipitación controlada no fue posible obtener fase pura.Fil: Gaona J., S.; Grupo de Ciencia y Tecnología de Materiales Cerámicos (CYTEMAC), Universidad del Cauca. Popayán, Colombia.Fil: Muñoz, J.R. ; Grupo de Ciencia y Tecnología de Materiales Cerámicos (CYTEMAC), Universidad del Cauca. Popayán, Colombia.Fil: Raigoza, C.F.V.; ; Grupo de Ciencia y Tecnología de Materiales Cerámicos (CYTEMAC), Universidad del Cauca. Popayán, Colombia.Fil: Ramirez, S., Grupo Catálisis, Departamento de Química, Universidad del Cauca. Popayán, Colombia.Fil: Caneiro, Alberto; Departamento de Caracterización de Materiales, Centro Atómico Bariloche, Bariloche, Argentina

Influence of the time of day on axial length and choroidal thickness changes to hyperopic and myopic defocus in human eyes

© 2019 Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 12 month embargo from date of publication (March 2019) in accordance with the publisher’s archiving policyResearch in animal models have shown that exposing the eye to positive or negative spectacle lenses can lead to predictable changes in eye growth. Recent research indicates that brief periods (1–2 h) of monocular defocus results in small, but significant changes in axial length and choroidal thickness of human subjects. However, the effects of the time of day on these ocular changes with defocus are not known. In this study, we examined the effects of monocular myopic and hyperopic defocus on axial length and choroidal thickness when applied in the morning (change between 10 a.m. and 12 p.m.) vs the evening (change between 5 and 7 p.m.) in young adult human participants (mean age, 23.44 ± 4.52 years). A series of axial length (using an IOL Master) and choroidal thickness (using an optical coherence tomographer) measurements were obtained over three consecutive days in both eyes. Day 1 (no defocus) examined the baseline ocular measurements in the morning (10 a.m. and 12 p.m.) and in the evening (5 and 7 p.m.), day 2 investigated the effects of hyperopic and myopic defocus on ocular parameters in the morning (subjects wore a spectacle lens with +3 or −3 DS over the right eye and a plano lens over the left eye between 10 a.m. and 12 p.m.), and day 3 examined the effects of defocus in the evening (+3 or −3 DS spectacle lens over the right eye between 5 and 7 p.m.). Exposure to myopic defocus caused a significant reduction in axial length and thickening of the subfoveal choroid at both times; but, compared to baseline data from day 1, the relative change in axial length (−0.021 ± 0.009 vs +0.004 ± 0.003 mm, p = 0.009) and choroidal thickness (+0.027 ± 0.006 vs +0.007 ± 0.006 mm, p = 0.011) with defocus were significantly greater for evening exposure to defocus than for the morning session. On the contrary, introduction of hyperopic defocus resulted in a significant increase in axial length when given in the morning (+0.026 ± 0.006 mm), but not in the evening (+0.001 ± 0.003 mm) (p = 0.047). Furthermore, hyperopic defocus resulted in a significant thinning of the choroid (p = 0.005), but there was no significant influence of the time of day on choroidal changes associated with hyperopic defocus (p = 0.672). Exposure to hyperopic and myopic defocus at different times of the day was also associated with changes in the parafoveal regions of the choroid (measured across 1.5 mm nasal and temporal choroidal regions on either side of the fovea). Our results show that ocular response to optical defocus varies significantly depending on the time of day in human subjects. These findings represent a potential interaction between the signal associated with the eye's natural diurnal rhythm and the visual signal associated with the optical defocus, making the eye perhaps more responsive to hyperopic defocus (or ‘go’ signal) in the morning, and to myopic defocus (or ‘stop’ signal) in the latter half of the day

Phase structure and thermal evolution in coating films and powders obtained by sol-gel process : Part II. ZrO2–2.5 mole% Y2O3

Powders and coatings of zirconia doped with 2.5 mole % yttria have been produced via the sol-gel route. The phase structure and subsequent thermal evolution in heating and cooling cycles have been investigated using mainly perturbed angular correlations spectroscopy. Thermal analyses and XRD as a function of temperature have also been performed to obtain complementary information. Upon heating, the amorphous gels crystallized into the tetragonal structure and showed the same hyperfine pattern and thermal behavior as observed in tetragonal zirconia obtained by the ceramic route: the two configurations of vacancies around zirconium ions denoted as t1 and t2 forms and their mutual t1 → t2 transformation. While the powder sample exhibited an incipient thermal instability above 1000 °C and underwent completely the t2 form to m–ZrO2 transition during subsequent, gradual cooling below 500 °C, the coating retained the tetragonal phase within the whole temperature range investigated. Hyperfine results suggest that the tetragonal phase stabilization is favored by the highly defective nature of the t1 form and consequently hardened by the availability of oxygen. The PAC derived activation energy for the fast diffusion of the oxygen vacancies inherent to the t2 form was determined as 0.54 ± 0.14 eV.Facultad de Ciencias Exacta

Revisiting the Crystal Structure of BaCe0.4Zr0.4Y0.2O3-δ Proton Conducting Perovskite and Its Correlation with Transport Properties

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.Fil: Basbus, Juan Felipe. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Arce, Mauricio Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Napolitano, Federico Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Troiani, Horacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Alonso, José Antonio. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Saleta, Martin Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; Argentina. Centro Nacional de Pesquisa em Energia e Materiais; BrasilFil: González, Miguel A.. Institut Laue Langevin; FranciaFil: Cuello, Gabriel Julio. Institut Laue Langevin; FranciaFil: Fernández Díaz, María Teresa. Institut Laue Langevin; FranciaFil: Pardo Sainz, Miguel. Universidad de Zaragoza. Instituto de Ciencias de Materiales de Aragon; EspañaFil: Bonanos, Nikolaos. Technical University of Denmark; DinamarcaFil: Jimenez, Catalina Elena. Helmholtz-Zentrum; AlemaniaFil: Giebeler, Lars. No especifíca;Fil: Figueroa, Santiago J. A.. Centro Nacional de Pesquisa em Energia e Materiais; BrasilFil: Caneiro, Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Serquis, Adriana Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; ArgentinaFil: Mogni, Liliana Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche | Comisión Nacional de Energía Atómica. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología. Unidad Ejecutora Instituto de Nanociencia y Nanotecnología - Nodo Bariloche; Argentin

Optical coherence tomography-based contact indentation for diaphragm mechanics in a mouse model of transforming growth factor alpha induced lung disease

This study tested the utility of optical coherence tomography (OCT)-based indentation to assess mechanical properties of respiratory tissues in disease. Using OCT-based indentation, the elastic modulus of mouse diaphragm was measured from changes in diaphragm thickness in response to an applied force provided by an indenter. We used a transgenic mouse model of chronic lung disease induced by the overexpression of transforming growth factor-alpha (TGF-a), established by the presence of pleural and peribronchial fibrosis and impaired lung mechanics determined by the forced oscillation technique and plethysmography. Diaphragm elastic modulus assessed by OCT-based indentation was reduced by TGF-a at both left and right lateral locations (p < 0.05). Diaphragm elastic modulus at left and right lateral locations were correlated within mice (r = 0.67, p < 0.01) suggesting that measurements were representative of tissue beyond the indenter field. Co-localised images of diaphragm after TGF-a overexpression revealed a layered fibrotic appearance. Maximum diaphragm force in conventional organ bath studies was also reduced by TGF-a overexpression (p < 0.01). Results show that OCT-based indentation provided clear delineation of diseased diaphragm, and together with organ bath assessment, provides new evidence suggesting that TGF-a overexpression produces impairment in diaphragm function and, therefore, an increase in the work of breathing in chronic lung disease

Prognostic Impact of Nutritional Status After Transcatheter Edge-to-Edge Mitral Valve Repair: The MIVNUT Registry

Background Malnutrition is associated with poor prognosis in several cardiovascular diseases. However, its prognostic impact in patients undergoing transcatheter edge-to-edge mitral valve repair (TEER) is not well known. This study sought to assess the prevalence, clinical associations, and prognostic consequences of malnutrition in patients undergoing TEER. Methods and Results A total of 892 patients undergoing TEER from the international MIVNUT (Mitral Valve Repair and Nutritional Status) registry were studied. Malnutrition status was assessed with the Controlling Nutritional Status score. The association of nutritional status with mortality was analyzed with multivariable Cox regression models, whereas the association with heart failure admission was assessed by Fine-Gray models, with death as a competing risk. According to the Controlling Nutritional Status score, 74.4% of patients with TEER had any degree of malnutrition at the time of TEER (75.1% in patients with body mass index <25?kg/m2, 72.1% in those with body mass index ?25?kg/m2). However, only 20% had moderate-severe malnutrition. TEER was successful in most of patients (94.2%). During a median follow-up of 1.6?years (interquartile range, 0.6-3.0), 267 (29.9%) patients died and 256 patients (28.7%) were admitted for heart failure after TEER. Compared with normal nutritional status moderate-severe malnutrition resulted a strong predictor of mortality (adjusted hazard ratio [HR], 2.1 [95% CI, 1.1-2.4]; P<0.001) and heart failure admission (adjusted subdistribution HR, 1.6 [95% CI, 1.1-2.4]; P=0.015). Conclusions Malnutrition is common among patients submitted to TEER, and moderate-severe malnutrition is strongly associated with increased mortality and heart failure readmission. Assessment of nutritional status in these patients may help to improve risk stratification

Management and outcomes of patients with left atrial appendage thrombus prior to percutaneous closure

Altres ajuts: Fundación Interhospitalaria para la Investigación Cardiovascular (FIC Foundation); Abbott.Objective: Left atrial appendage (LAA) thrombus has heretofore been considered a contraindication to percutaneous LAA closure (LAAC). Data regarding its management are very limited. The aim of this study was to analyse the medical and invasive treatment of patients referred for LAAC in the presence of LAA thrombus. Methods: This multicentre observational registry included 126 consecutive patients referred for LAAC with LAA thrombus on preprocedural imaging. Treatment strategies included intensification of antithrombotic therapy (IAT) or direct LAAC. The primary and secondary endpoints were a composite of bleeding, stroke and death at 18 months, and procedural success, respectively. Results: IAT was the preferred strategy in 57.9% of patients, with total thrombus resolution observed in 60.3% and 75.3% after initial and subsequent IAT, respectively. Bleeding complications and stroke during IAT occurred in 9.6% and 2.9%, respectively, compared with 3.8% bleeding and no embolic events in the direct LAAC group before the procedure. Procedural success was 90.5% (96.2% vs 86.3% in direct LAAC and IAT group, respectively, p=0.072), without cases of in-hospital thromboembolic complications. The primary endpoint occurred in 29.3% and device-related thrombosis was found in 12.8%, without significant difference according to treatment strategy. Bleeding complications at 18 months occurred in 22.5% vs 10.5% in the IAT and direct LAAC group, respectively (p=0.102). Conclusion: In the presence of LAA thrombus, IAT was the initial management strategy in half of our cohort, with initial thrombus resolution in 60% of these, but with a relatively high bleeding rate (∼10%). Direct LAAC was feasible, with high procedural success and absence of periprocedural embolic complications. However, a high rate of device-related thrombosis was detected during follow-up