High temperature internal friction in a Ti–46Al–1Mo–0.2Si intermetallic, comparison with creep behaviour

Advanced gamma-TiAl based intermetallics Mo-bearing have been developed to obtain the fine-grained microstructure required for superplastic deformation to be used during further processing. In the present work we have studied an alloy of Ti-46.8Al-1Mo-0.2Si (at%) with two different microstructures, ascast material with a coarse grain size above 300 mu m, and the hot extruded material exhibiting a grain size smaller than 20 mu m. We have used a mechanical spectrometer especially developed for high temperature internal friction measurements to study the defect mobility processes taking place at high temperature. The internal friction spectra at different frequencies has been studied and analyzed up to 1360 K in order to characterize the relaxation processes appearing in this temperature range. A relaxation peak, with a maximum in between 900 K and 1080 K, depending on the oscillating frequency, has been attributed to Ti-atoms diffusion by the stress-induced reorientation of Al-V-Ti-Al elastic dipoles. The high temperature background in both microstructural states, as-cast and extruded, has been analyzed, measuring the apparent activation parameters, in particular the apparent energies of E-cast(IF) = 4.4 +/- 0.05 eV and E-ext(IF) = 4.75 +/- 0.05 eV respectively. These results have been compared to those obtained on the same materials by creep deformation. We may conclude that the activation parameters obtained by internal friction analysis, are consistent with the ones measured by creep. Furthermore, the analysis of the high temperature background allows establish the difference on creep resistance for both microstructural states. (c) 2015 Acta Materialia Inc. Published by Elsevier Ltd.This work was supported by the Spanish MICINN project CONSOLIDER-INGENIO 2010 CSD2009-00013, as well as by the Consolidated Research Group IT-10-310 from the Education Department and the project ETORTEK ACTIMAT from the Industry Department of the Basque Governmen

Effects of formalin fixation on polarimetric properties of brain tissue: fresh or fixed?

Imaging Mueller polarimetry (IMP) appears as a promising technique for real-time delineation of healthy and neoplastic tissue during neurosurgery. The training of machine learning algorithms used for the image post-processing requires large data sets typically derived from the measurements of formalin-fixed brain sections. However, the success of the transfer of such algorithms from fixed to fresh brain tissue depends on the degree of alterations of polarimetric properties induced by formalin fixation (FF). Comprehensive studies were performed on the FF induced changes in fresh pig brain tissue polarimetric properties. Polarimetric properties of pig brain were assessed in 30 coronal thick sections before and after FF using a wide-field IMP system. The width of the uncertainty region between gray and white matter was also estimated. The depolarization increased by 5% in gray matter and remained constant in white matter following FF, whereas the linear retardance decreased by 27% in gray matter and by 28% in white matter after FF. The visual contrast between gray and white matter and fiber tracking remained preserved after FF. Tissue shrinkage induced by FF did not have a significant effect on the uncertainty region width. Similar polarimetric properties were observed in both fresh and fixed brain tissues, indicating a high potential for transfer learning

Physical Education through a joint curriculum in secondary schools

Resumen basado en el de la publicaciónLa Educación Física ha de adoptar un papel principal en la sociedad del bienestar, del tiempo libre y del ocio. Teniendo en cuenta los resultados de diversos estudios a nivel europeo y norteamericano, en relación a la Educación Física recibida por parte de los escolares, se plantea un proyecto con el objetivo principal de diseñar un currículum común del área de Educación Física entre los distintos centros de la zona de Almería, teniendo en cuenta la variedad y novedad de los contenidos a plantear en clase, intentando alejarse de los que tradicionalmente han predominado en las sesiones de Educación Física. Se espera que un mayor y amplio número de experiencias, que parten de los intereses del alumnado, tenga unos efectos positivos en la actitud y motivación de los mismos, tanto en las clases como en un impacto positivo en la adhesión a la actividad física a lo largo de toda su vida.AndalucíaES

Propuesta de seminario de actualización farmacoterapéutica sobre hipertensión arterial

Por la repercusión que tiene sobre los índices de morbilidad y mortalidad a nivel internacional, la hipertensión arterial constituye un desafío para la Atención Primaria de Salud. En los últimos años se ha desarrollado un completo arsenal terapéutico de eficacia demostrada, sin embargo, no se alcanzan los logros esperados con el tratamiento, al menos en términos poblacionales, por lo que los investigadores en esta esfera realizan infinitos esfuerzos para dar solución a este problema de salud y las complicaciones que de él se derivan. Una de las formas de contribuir a solucionar esta situación es mantener actualizado al personal médico y promover en los estudiantes un pensamiento científico prescriptivo, por lo que proponemos una forma de desarrollar los seminarios de actualización farmacoterapéutica, tomando como ejemplo la hipertensión arterial

Determinación de pigmentos en orégano (Poliomintha bustamantaB. L. Turner.) en dos condiciones de crecimiento.

El “orégano de Nuevo León” Poliomintha bustamanta B. L Turner., es una de las especies de orégano más importantes del País, apreciado y comercializado, por su uso como condimento y para la producción de aceites esenciales. Se encuentra en forma silvestre en las regiones áridas y semiáridas, cuyos ambientes es recolectada para su aprovechamiento y poco se ha cuidado su manejo y recuperación natural, es necesario realizar investigaciones encaminadas a establecer cultivos comerciales de esta planta. El objetivo fue evaluar en espectrometría de luz visible el contenido de pigmentos de la hoja bajo dos condiciones de crecimiento. Se colectaron hojas de orégano de plantas silvestres en el municipio de Higueras, N.L., y de plántulas de invernadero. El orégano silvestre, mostró una mayor concentración de pigmentos que el de invernadero. Estos resultados muestran diferencia significativa (P<0.01) entre el origen del orégano y el estado de la muestra, observándose en las muestras secas de orégano silvestre el mayor contendido de clorofila total, clorofila a, carotenos totales y carotenos amarillos. Mientras que las muestras secas de orégano de invernadero presentaron el mayor contenido de carotenos rojos. El cultivo de Orégano en invernadero presenta una menor concentración de pigmentos que el orégano silvestre

Disconnecting Symmetry Breaking from Seeded Growth for the Reproducible Synthesis of High Quality Gold Nanorods

https://pubs.acs.org/doi/suppl/10.1021/acsnano.8b09658/suppl_file/nn8b09658_si_002.pdfOne of the major difficulties hindering the widespread application of colloidal anisotropic plasmonic nanoparticles is the limited robustness and reproducibility of multistep synthetic methods. We demonstrate herein that the reproducibility and reliability of colloidal gold nanorod (AuNR) synthesis can be greatly improved by disconnecting the symmetry-breaking event from the seeded growth process. We have used a modified silver-assisted seeded growth method in the presence of the surfactant hexadecyltrimethylammonium bromide and n-decanol as a co-surfactant to prepare small AuNRs in high yield, which were then used as seeds for the growth of high quality AuNR colloids. Whereas the use of n-decanol provides a more-rigid micellar system, the growth on anisotropic seeds avoids sources of irreproducibility during the symmetry breaking step, yielding uniform AuNR colloids with narrow plasmon bands, ranging from 600 to 1270 nm, and allowing the fine-tuning of the final dimensions. This method provides a robust route for the preparation of high quality AuNR colloids with tunable morphology, size, and optical response in a reproducible and scalable manner

The methodology of surveillance for antimicrobial resistance and healthcare-associated infections in Europe (SUSPIRE): a systematic review of publicly available information.

OBJECTIVES: Surveillance is a key component of any control strategy for healthcare-associated infections (HAIs) and antimicrobial resistance (AMR), and public availability of methodologic aspects is crucial for the interpretation of the data. We sought to systematically review publicly available information for HAIs and/or AMR surveillance systems organized by public institutions or scientific societies in European countries. METHODS: A systematic review of scientific and grey literature following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines was performed. Information on HAIs and/or AMR surveillance systems published until 31 October 2016 were included. RESULTS: A total of 112 surveillance systems were detected; 56 from 20 countries were finally included. Most exclusions were due to lack of publicly available information. Regarding AMR, the most frequent indicator was the proportion of resistant isolates (27 of 34 providing information, 79.42%); only 18 (52.9%) included incidence rates; the data were only laboratory based in 33 (78.5%) of the 42 providing this information. Regarding HAIs in intensive care units, all 22 of the systems providing data included central line-associated bloodstream infections, and 19 (86.3%) included ventilator-associated pneumonia and catheter-associated urinary tract infections; incidence density was the most frequent indicator. Regarding surgical site infections, the most frequent procedures included were hip prosthesis, colon surgery and caesarean section (21/22, 95.5%). CONCLUSIONS: Publicly available information about the methods and indicators of the surveillance system is frequently lacking. Despite the efforts of European Centre for Disease Control and Prevention (ECDC) and other organizations, wide heterogeneity in procedures and indicators still exists

Biopolymer-based structuring of liquid oil into soft solids and oleogels using water-continuous emulsions as templates

Physical trapping of a hydrophobic liquid oil in a matrix of water-soluble biopolymers was achieved using a facile two-step process by first formulating a surfactant-free oil-in-water emulsion stabilized by biopolymers (a protein and a polysaccharide) followed by complete removal of the water phase (by either high- or low-temperature drying of the emulsion) resulting in structured solid systems containing a high concentration of liquid oil (above 97 wt %). The microstructure of these systems was revealed by confocal and cryo-scanning electron microscopy, and the effect of biopolymer concentrations on the consistency of emulsions as well as the dried product was evaluated using a combination of small-amplitude oscillatory shear rheometry and large deformation fracture studies. The oleogel prepared by shearing the dried product showed a high gel strength as well as a certain degree of thixotropic recovery even at high temperatures. Moreover, the reversibility of the process was demonstrated by shearing the dried product in the presence of water to obtain reconstituted emulsions with rheological properties comparable to those of the fresh emulsion