Calculation of the orientation relationships of directionally solidified eutectic ceramics by a modified Coincidence of Reciprocal Lattice Points model (CRLP)

The Coincidence of Reciprocal Lattice Points (CRLP) method was used to predict, according to geometric considerations, the most favorable orientation relationships (ORs) between the component phases in a family of directionally solidified eutectic ceramics (DSEC) (NiO-YSZ, CoO-YSZ, NiO-CeO2, NiO-GDC, CoO-CeO2, and CoO-GDC) grown by the laser floating zone method. The ORs predicted by the CRLP model are consistent with those experimentally found in a previous work by means of Electron Backscatter Diffraction (EBSD). In this article, we also present a modification to the model with the aim of taking into account that the most stable ceramic-ceramic interfaces are usually formed between atomic planes with low Miller indices, due to their higher atomic density and bigger interplanar spacing. Thus, we introduce in the calculation of the overall coincidence volume a weighting factor which is a function of the interplanar spacing. This modified CRLP method has been applied to the aforementioned eutectic ceramics, and the results are presented and discussed in comparison with the traditional CRLP results and the experimental findings.This study was funded by the MAT2012-30763 project, which is financed by the Spanish Government (Ministerio de Economía y Competitividad) and the Feder program of the European Union.Peer Reviewe

Antimicrobial residue assessment in 5, 357 commercialized meat samples from the Spain-France cross-border area: A new approach for effective monitoring

Although antimicrobials are valuable allies in animal production, their extended use has led to unexpected threats associated with the emergence and propagation of antimicrobial resistance. Moreover, when withdrawal periods in food-producing animals are not observed, antimicrobial residues can access the food chain, causing direct toxicity, allergies, and/or intestinal microbiota dysbiosis in consumers. Given that Spain and France are the largest meat producers in the EU and also count among the top consumers of meat, our study''s aim was to investigate the presence of antimicrobials in commercialized meat purchased in the Spain-France cross-border area (POCTEFA region). 5, 357 meat samples were collected from different animal species and a variety of different retailer types in Spain (Zaragoza, Bilbao, and Logroño) as well as in France (Toulouse and Perpignan). Meat samples were analysed by a screening method (Explorer®+QuinoScan®), yielding 194 positive samples, which were further evaluated by UPLC-QTOF (Ultra Performance Liquid Chromatography-Quadrupole Time of Flight) for confirmation. Chromatographic analyses found antimicrobial residues in 30 samples, although only 5 of them (0.093% of initial samples) were non-compliant according to the current legislation. Further studies suggested that this mismatch between screening and confirmatory analyses might be due to the presence of biologically active metabolites derived from degradation of antimicrobials that were not identified by the targeted UPLC-QTOF method, but which might play a decisive role in the inhibition of the biological Explorer® test. Although chromatographic techniques detect the marker compounds determined by European and national regulations, and although they are the methods selected for official control of antimicrobials in food, certain unknown metabolites might escape their monitoring. This thus suggests that biological tests are the most adequate ones in terms of ideal consumer health protection

Factors related to the development of health-promoting community activities in Spanish primary healthcare: two case-control studies.

Objective Spanish primary healthcare teams have the responsibility of performing health-promoting community activities (CAs), although such activities are not widespread. Our aim was to identify the factors related to participation in those activities. Design Two case–control studies. setting Performed in primary care of ve Spanish regions. subjects In the rst study, cases were teams that performed health-promoting CAs and controls were those that did not. In the second study (on case teams from the rst study), cases were professionals who developed these activities and controls were those who did not. Main outcome measures Team, professional and community characteristics collected through questionnaires (team managers/professionals) and from secondary sources. results The rst study examined 203 teams (103 cases, 100 controls). Adjusted factors associated with performing CAs were percentage of nurses (OR 1.07, 95% CI 1.01 to 1.14), community socioeconomic status (higher vs lower OR 2.16, 95% CI 1.18 to 3.95) and performing undergraduate training (OR 0.44, 95% CI 0.21 to 0.93). In the second study, 597 professionals responded (254 cases, 343 controls). Adjusted factors were professional classi cation (physicians do fewer activities than nurses and social workers do more), training in CAs (OR 1.9, 95% CI 1.2 to 3.1), team support (OR 2.9, 95% CI 1.5 to 5.7), seniority (OR 1.06, 95% CI 1.03 to 1.09), nursing tutor (OR 2.0, 95% CI 1.1 to 3.5), motivation (OR 3.7, 95% CI 1.8 to 7.5), collaboration with non-governmental organisations (OR 1.9, 95% CI 1.2 to 3.1) and participation in neighbourhood activities (OR 3.1, 95% CI 1.9 to 5.1). Conclusions Professional personal characteristics, such as social sensitivity, profession, to feel team support or motivation, have in uence in performing health-promoting CAs. In contrast to the opinion expressed by many professionals, workload is not related to performance of health-promoting CAs

Genetic ancestry is associated with colorectal adenomas and adenocarcinomas in Latino populations

Colorectal cancer rates in Latin American countries are less than half of those observed in the United States. Latin Americans are the resultant of generations of an admixture of Native American, European, and African individuals. The potential role of genetic admixture in colorectal carcinogenesis has not been examined. We evaluate the association of genetic ancestry with colorectal neoplasms in 190 adenocarcinomas, 113 sporadic adenomas and 243 age- and sex-matched controls enrolled in a multicentric case–control study in Colombia. Individual ancestral genetic fractions were estimated using the STRUCTURE software, based on allele frequencies and assuming three distinct population origins. We used the Illumina Cancer Panel to genotype 1,421 sparse single-nucleotide polymorphisms (SNPs), and Northern and Western European ancestry, LWJ and Han Chinese in Beijing, China populations from the HapMap project as references. A total of 678 autosomal SNPs overlapped with the HapMap data set SNPs and were used for ancestry estimations. African mean ancestry fraction was higher in adenomas (0.13, 95% confidence interval (95% CI)=0.11–0.15) and cancer cases (0.14, 95% CI=0.12–0.16) compared with controls (0.11, 95% CI=0.10–0.12). Conditional logistic regression analysis, controlling for known risk factors, showed a positive association of African ancestry per 10% increase with both colorectal adenoma (odds ratio (OR)=1.12, 95% CI=0.97–1.30) and adenocarcinoma (OR=1.19, 95% CI=1.05–1.35). In conclusion, increased African ancestry (or variants linked to it) contributes to the increased susceptibility of colorectal cancer in admixed Latin American population

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Estudios microestructurales y cristalográficos de cerámicas eutécticas solidificadas direccionalmente para aplicaciones energéticas

Esta tesis se presenta por la modalidad de compendio de artículos. En ella se recogen los estudios microestructurales y cristalográficos de diferentes cerámicas eutécticas solidificadas direccionalmente (directionally solidified eutectic ceramics, dsecs) con diversas aplicaciones potenciales, fundamentalmente energéticas. Como eutécticos, estos materiales se caracterizan por tener una microestructura muy fina y homogénea (ya sea irregular, fibrilar o laminar) con interfases limpias, y por su solidificación direccional, son altamente texturados. Los objetivos principales de esta tesis han sido avanzar en la comprensión de los factores que determinan las relaciones de orientación y planos de interfase entre las fases y relacionar las propiedades del material con su microestructura. En 1979, minford et al. establecieron que los dos principales factores que determinan el plano de interfase y la relación de orientación en las dsec son el balance de carga en la interfase y la minimización del desajuste entre las redes. El estudio de dichos factores, desde un punto de vista teórico, se ha llevado a cabo mediante el cálculo del balance de densidad de carga iónica en la interfase y de la coincidencia de puntos de la red recíproca (coincidence of reciprocal lattice points, crlp) para la familia de dsecs compuesta por los eutécticos nio-ysz (circona dopada con itrio), coo-ysz, nio-ceo2, coo-ceo2, nio-gdc (ceria dopada con gadolinio) y coo-gdc. Estos materiales, tras su reducción, se convierten en cermets porosos con excelentes propiedades que les permite ser utilizados como ánodos en pilas de combustible de óxido sólido (solid oxide fuel cells, sofc). Desde el punto de vista experimental, la orientación cristalográfica se ha estudiado por medio de difracción de electrones retrodispersados (electron backscatter diffraction, ebsd) en el microscopio electrónico de barrido (scanning electron microscope, sem). Esta técnica fue aplicada a la familia de eutécticos anteriormente mencionada, así como a otras dsec. Concretamente, se estudiaron: el eutéctico lif-liyf4, con aplicación en el campo de la fotónica; el eutéctico ternario basado en alúmina al2o3-er3al5o12-esz (circona dopada con erbio), con aplicación en dispositivos termofotovoltaicos; y el eutéctico mn3o4-ymnsz, de aplicación en el campo de las electrocerámicas y el magnetismo. Para todas estas dsec, se determinaron sus direcciones de crecimiento, relaciones de orientación entre las fases, y en algunos casos, también sus planos de interfase. Para la dsec al2o3-er3al5o12-esz, se estudió también su estabilidad microestructural tras un tratamiento térmico a alta temperatura (1600 ºc), encontrándose que este material apenas se degradó tras 100 h de envejecimiento. El estudio de la familia nio-ysz,coo-ysz, nio-ceo2, coo-ceo2, nio-gdc y coo-gdc integra el grueso de esta tesis doctoral. Además de los experimentos de ebsd, se realizó un microanálisis de rayos x característico (x-ray energy dispersive spectroscopy, eds) para determinar y cuantificar la presencia de segregación de átomos de gadolinio hacia la interfase en los eutécticos nio-gdc y coo-gdc. estos experimentos pusieron de manifiesto la relevancia del primer criterio de minford en la formación de interfases de baja energía. También se estudió la reducción de los eutécticos nio-gdc y coo-gdc por medio de ebsd, difracción de rayos x y microscopía de barrido y transmisión. Las interfases resultantes en los cermets dependen de si la reducción de los óxidos nio y coo se produce mediante un proceso topotáctico, o de las reorientaciones que tienen lugar. La naturaleza de las interfases tendrá un impacto directo sobre la adhesión de las fases y su estabilidad a alta temperatura, y por lo tanto, sobre su funcionalidad como ánodos en sofc.Peer Reviewe

Electron backscatter diffraction analysis of non-conductive samples using in-situ charge compensation

Electron backscatter diffraction (EBSD) is a powerful technique for structural characterization of micro- or nanocrystalline samples in the scanning electron microscope (SEM). Reliable EBSD analysis of non-conductive samples has so far required the use of conductive coatings or variable pressure (VP) SEM. An in-situ charge compensation system provides improved EBSD analysis of non-conductive samples without the drawbacks of these conventional methods. Similar to VP-SEM, charge neutralisation is achieved by gas ionization, but at negligible loss of resolution due to a significantly reduced interaction volume of beam and backscattered electrons with gas particles.Angel Larrea and Sonia Serrano-Zabaleta acknowledge funding from project MAT2012-30763 and the use of Servicio General de Apoyo a la Investigación-SAI, Universidad de Zaragoza.Peer Reviewe

Microstructural stability and orientation relationships of directionally solidified Al2O3-Er3Al5O12-ZrO2 eutectic ceramics up to 1600°C

Directionally Solidified Eutectics: Selected Papers from DSEC IV.Al2O3-Er3Al5O12-ZrO2 eutectic ceramic rods were directionally solidified using the laser floating zone method at different growth rates, 25, 350 and 1200mm/h. The microstructure obtained, in terms of both morphology and phase size, was strongly dependent on the growth rate. However, electron backscatter diffraction experiments showed that the growth directions were the same for all the processing rates, [0001]Al2O3//[100]EAG//[100]ZrO2. The microstructural stability was investigated up to 1600°C as a function of the growth rate. Ceramics with the largest phase size presented high stability, their microstructure remaining substantially unchanged at the highest annealing temperature for 100h. Eutectics processed at higher growth rates and with a finer microstructure showed coarsening after heat treatments. The sample grown at 350mm/h coarsened at 1450°C whereas the eutectic solidified at 1200mm/h thickened at 1400°C. The growth directions remain unaffected for all growth rates. The mechanisms of microstructural coarsening were investigated. © 2014 Elsevier Ltd.The authors acknowledge the financial support from the Ministerio de Ciencia e Innovación de España and from the FEDER funds of the European Community under project MAT2009-13979-C03-03. The authors would like to acknowledge the use of Servicio General de Apoyo a la Investigación-SAI, Universidad de Zaragoza. S. Serrano-Zabaleta thanks the Spanish Government for a grant and M.C. Mesa also thanks the Gobierno de Aragón for a grant.Peer Reviewe

Orientation relationships and interfaces in directionally solidified eutectics for solid oxide fuel cell anodes

Directionally Solidified Eutectics: Selected Papers from DSEC IV.Orientation relationships (ORs), interface planes and growth directions of the directionally solidified eutectics NiO-YSZ, CoO-YSZ, NiO-CeO2, NiO-GDC, CoO-CeO2 and CoO-GDC have been determined by means of electron backscatter diffraction (EBSD). The eutectics were prepared by the laser floating zone technique at different growth rates (10-200mm/h) to explore dissimilar lamellar spacing. The majority OR is characterized by a single (111)NiO/CoO//(001)YSZ/GDC/CeO2 interface plane and two different growth directions: [01-1]NiO/CoO//[010]YSZ/GDC/CeO2 and [11-0]NiO/CoO~//[110]YSZ/GDC/CeO2, the OR being the same for both cases. In addition, a cube-on-cube OR, where the crystallographic axes of the component phases are parallel, has also been observed. These experimental results are discussed in terms of the ionic charge balance and the lattice misfit at the interface. The coincidence of reciprocal lattice points model (CRLP) has also been applied to the NiO-YSZ case. The most favourable ORs predicted by the CRLP model are consistent with the experimental findings. © 2013 Elsevier Ltd.This study was funded by the Spanish Government and Feder program of the European Community (projects MAT2009-14324-C02-01 and MAT2012-30763).Peer Reviewe

Directional solidification of the eutectic LiF–LiYF4 using Bridgman and micro-pulling down techniques: Microstructural study and some properties

Directionally Solidified Eutectics: Selected Papers from DSEC IV.The eutectic LiF–LiYF4 has been solidified by Bridgman and micro-pulling down (mPD) at pulling rates from 4 to 300 mm/h. The microstructure changes from a coupled, interpenetrated-like one to macrofaceted colonies composed of an approximately triangular arrangement of LiF fibers inside the LiYF4 matrix as the pulling rate increases. The cross-over pulling rate is around 3 times larger for the mPD method, corresponding to its larger solidification gradient. The crystallographic growth direction of the matrix phase was found using EBSD. Effective medium estimations of the THz permittivity of the composite predict around the interphase phonon-polariton resonance (wavelength around 17.5 μm) a small permittivity hyperbolic behavior specific of the ordered composite that is tolerant to different relative orientations. Water etching of polished cross-sections constitutes a very simple procedure to generate surface micro-holes of predefined size in the LiYF4 matrix.Authors would like to acknowledge the financial support by EU under the project NMP4-SL-2008-213669-ENSEMBLE. MFA acknowledges Ministerio de Educación, Cultura y Deporte (Spain) for the FPU scholarship.Peer reviewe