Effect of cooling rate during solidification on the hard phases of M23C6-type of cast CoCrMo alloy

Microstructural morphology of CoCrMo alloy by control of the cooling rate during the solidification was investigated. Samples were obtained using both an induction furnace for slow cooling rate and electric arc furnace for fast cooling rate. Microstructural characterizations were performed with metallographic techniques. It was found that the difference between the formation temperature of hard secondary phases of M23C6-type carbides determine the reduction of carbide size by increasing the cooling rate

Características citopatológicas del carcinoma de células acinares (CCA) de glándula salival: a propósito de cuatro observaciones

Objetivo: Presentar las características citopatológicas del carcinoma acinar (CCA), así como su correlación cito-histológica, comentando los problemas de diagnóstico diferencial de esta entidad en base a cuatro observaciones estudiadas mediante PAAF. Casos clínicos: Dos varones de 52 y 53 años, una mujer de 79 años, y una niña de 12 años que presentaron tumoraciones localizadas en territorio parotídeo (casos 1, 2 y 4), y a nivel laterocervical (caso 3). En tres pacientes, la PAAF fue, junto a los estudios de imagen, la primera aproximación diagnóstica; correspondiendo el caso 3 a una punción de adenopatías laterocervicales metastásicas en una paciente con antecedentes de CCA de parótida. Hallazgos citológicos: Las extensiones citológicas mostraron abundante celularidad tumoral dispuesta en pequeñas placas monocapa, formando estructuras acinares, o como células aisladas. Es de destacar la abundancia de núcleos desnudos en el fondo de los frotis, y la ausencia de grasa y de epitelio ductal. Las células poseían núcleos monomorfos redondeados u ovales, nucleólo poco evidente y abundante citoplasma granular o finamente vacuolado. Discusión: La PAAF proporciona información esencial en la actuación diagnóstico-terapeútica de las tumoraciones de la glándula salival, resultando esta metodología muy sensible en su eficacia diagnóstica. La identificación de los CCA frecuentemente presenta dificultades, debido a la gran similitud citológica de las células tumorales con el componente acinar normal propio de la glándula salival. El diagnóstico diferencial se plantea, fundamentalmente, con carcinomas de células claras, con carcinomas mucoepidermoides, con el tumor de Warthin y con los oncocitomas. Nuestras observaciones confirman la validez de la PAAF en una primera aproximación diagnóstica de estas lesiones tumorales accesibles a la punción directa.Objective: To present the cytopathological characteristics of acinic cell carcinoma (ACC) as well as its cyto-histological correlation, commenting on the differential diagnostic problems of this entity based on four observations studied using fine-needle aspiration biopsy (FNAB). Clinical Cases: Two males of 52 and 53 years of age, one 79 year-old woman and a girl of 12 years of age, who presented tumors located in the parotid area (cases 1, 2 and 4) and at the laterocervical level (case 3). In 3 patients, the FNAB was, together with the image studies, the first diagnostic indication; case 3 corresponding to a puncture of metastatic laterocervical adenopathies in a patient with a history of parotid ACC. Cytological findings: The cytologic smears revealed abundant tumoral cellularity arranged in small monolayered sheets, forming acinar structures or isolated cells. The abundance of bare nuclei at the background of the smears, and the absence of adipose tissue and ductal epithelium are highlighted. The cells possessed round or oval monomorphic nuclei, few nucleoli and abundant granular or finely vacuolate cytoplasm. Discussion: FNAB provides essential information on the diagnostic- therapeutic management of salivary gland tumors; this methodology is highly sensitive in its diagnostic efficacy. The diagnosis of ACCs frequently presents difficulties, owing to the great cytologic similarity of the tumor cells with the normal acinar component of the salivary gland. The differential diag-nosis is considered, fundamentally, with clear cell carcinomas, mucoepidermoid carcinomas, Warthin's tumor, and oncocytomas. Our observations confirm the validity of FNAB in a first diagnostic approximation for those lesions accessible to direct puncture

Four millennia of Iberian biomolecular prehistory illustrate the impact of prehistoric migrations at the far end of Eurasia

Population genomic studies of ancient human remains have shown how modern-day European population structure has been shaped by a number of prehistoric migrations. The Neolithization of Europe has been associated with large-scale migrations from Anatolia, which was followed by migrations of herders from the Pontic steppe at the onset of the Bronze Age. Southwestern Europe was one of the last parts of the continent reached by these migrations, and modern-day populations from this region show intriguing similarities to the initial Neolithic migrants. Partly due to climatic conditions that are unfavorable for DNA preservation, regional studies on the Mediterranean remain challenging. Here, we present genome-wide sequence data from 13 individuals combined with stable isotope analysis from the north and south of Iberia covering a four-millennial temporal transect (7, 500–3, 500 BP). Early Iberian farmers and Early Central European farmers exhibit significant genetic differences, suggesting two independent fronts of the Neolithic expansion. The first Neolithic migrants that arrived in Iberia had low levels of genetic diversity, potentially reflecting a small number of individuals; this diversity gradually increased over time from mixing with local hunter-gatherers and potential population expansion. The impact of post-Neolithic migrations on Iberia was much smaller than for the rest of the continent, showing little external influence from the Neolithic to the Bronze Age. Paleodietary reconstruction shows that these populations have a remarkable degree of dietary homogeneity across space and time, suggesting a strong reliance on terrestrial food resources despite changing culture and genetic make-up

Magnetic study on biodistribution and biodegradation of oral magnetic nanostructures in the rat gastrointestinal tract

We have undertaken a magnetic study on the oral biodistribution and biodegradation of nude maghemite nanoparticles of 10 nm average size (MNP) and probiotic bacteria, Lactobacillus fermentum, containing thousands of these same nanoparticles (MNP-bacteria). Using AC magnetic susceptibility measurements of the stomach, small intestine, cecum and large intestine obtained after rat sacrifice, and iron content determination by ICP-OES, we have monitored the biodistribution and biodegradation of the maghemite nanoparticles along the gastrointestinal tract, after oral administration of both MNP and MNP-bacteria. The results revealed that the amount of magnetic nanoparticles accumulated in intestines is sensibly higher when MNP-bacteria were administered, in comparison with MNP. This confirms our initial hypothesis that the use of probiotic bacteria is a suitable strategy to assist the magnetic nanoparticles to overcome the stomach medium, and to achieve their accumulation in intestines. This finding opens doors to different applications. Since iron absorption in humans takes place precisely in the intestines, the use of MNP-bacteria as an iron supplement is a definite possibility. We have actually illustrated how the administration of MNP-bacteria to iron-deficient rats corrects the iron levels after two weeks of treatment

Enhancing the hydrogen transfer catalytic activity of hybrid carbon nanotube-based NHC–iridium catalysts by increasing the oxidation degree of the nanosupport

CVD-grown multiwalled carbon nanotubes were purified by applying four different treatments with increasing oxidation severity. The growing severity of the treatment results in progressive oxygen functionalization of the surface along with introduction of an increasing quantity of defects on the carbon nanotube walls. Iridium-N-heterocyclic carbene complexes were covalently anchored to those oxidized surfaces through their surface carboxylic acids via acetyl linkers. The carbon nanotube-based iridium-NHC hybrid materials developed are active in the hydrogen-transfer reduction of cyclohexanone to cyclohexanol with 2-propanol/KOH as hydrogen source but with rather different activity. The catalytic activity of the hybrid catalysts is strongly influenced by the type and amount of oxygenated functionalization resulting from the treatment applied to the support, being the most active and the most oxidized material.The authors thank the Spanish Ministry of Economy and Competitiveness (MINECO/FEDER) (Projects Consolider Ingenio 2010 CSD2009-00050 and CTQ2013-42532-P) and the Diputación General de Aragón (FSE-E07 and FSE-E69) for their financial support. Dr. P. A. thanks MINECO for a Ramón y Cajal contract. M. B. acknowledges his fellowship from MECD (AP2010-0025).Peer Reviewe

Lightweight conical components for rotational parabolic domes: geometric definition, structural behaviour, optimisation and digital fabrication

Although initially intended for academic purposes, the research shown in this paper was drawn towards the development of hollow lightweight conical com-ponents to materialise rotational parabolic domes. The starting point is a projec-tive interpretation of an Archimedean property of rotational paraboloid planar sections. This is used to discretise the parabolic surface with a set of tangent ellipses obtained via planar circle-packing algorithms. The ellipses are then mate-rialised with components composed of three truncated conical surfaces, which may be composed of several laminar materials. The geometry and economy of the material, the good structural behaviour, the simple solution for fabrication and assembly, and the tests on a full-scale prototype prove this component to be an efficient self-supporting system for wide-span structures against the use of solid boundary rings, not only for rotational parabolic domes, but also for a possible translation to other types of surface

La interfaz de usuario como punto de partida para la creación automática de aplicaciones móviles – un enfoque basado en MDD

Las aplicaciones móviles requieren una interfaz reducida y estandarizada paralograr que el usuario tenga una buena experiencia de uso. Particularmente lasaplicaciones que administran datos utilizan controles de interfaz generales quepermiten realizar todas las operaciones necesarias con dichos datos (listados,menús, pantallas de edición y de búsqueda). Tomando como base esos controles de interfaz de usuario se diseña una metodología de modelado basada en MDD(Model Driven Development), mediante la cual es posible generarautomáticamente aplicaciones web móviles con el solo hecho de configurar losdatos a visualizar en la interfaz y definir cómo será la navegación dentro delsistema. La configuración de los componentes está basada en un primer modeloque representa los datos que administrará la aplicación. Esta metodología estábasada en UML (Unified Modelling Language) y se define mediante una extensión conservativa de dicho lenguaje especificada en un profile de UML y una serie de restricciones. Para soportar la metodología de modelado se ha desarrollado una herramienta que permite modelar y realizar las transformaciones entre modelos que son necesarios para poder generar el código fuente 100% funcional de una aplicación

The user interface as a starting point for the automatic creation of mobile applications – an approach based on MDD

Las aplicaciones móviles requieren una interfaz reducida y estandarizada paralograr que el usuario tenga una buena experiencia de uso. Particularmente lasaplicaciones que administran datos utilizan controles de interfaz generales quepermiten realizar todas las operaciones necesarias con dichos datos (listados,menús, pantallas de edición y de búsqueda). Tomando como base esos controles de interfaz de usuario se diseña una metodología de modelado basada en MDD(Model Driven Development), mediante la cual es posible generarautomáticamente aplicaciones web móviles con el solo hecho de configurar losdatos a visualizar en la interfaz y definir cómo será la navegación dentro delsistema. La configuración de los componentes está basada en un primer modeloque representa los datos que administrará la aplicación. Esta metodología estábasada en UML (Unified Modelling Language) y se define mediante una extensión conservativa de dicho lenguaje especificada en un profile de UML y una serie de restricciones. Para soportar la metodología de modelado se ha desarrollado una herramienta que permite modelar y realizar las transformaciones entre modelos que son necesarios para poder generar el código fuente 100% funcional de una aplicación.Mobile applications require a reduced and standardized interface to ensure that the user has a good user experience. Particularly the Applications that manage data use general interface controls that allow you to perform all the necessary operations with said data (lists, menus, editing and search screens). Based on these controls of user interface a modeling methodology based on MDD is designed (Model Driven Development), through which it is possible to generate automatically mobile web applications just by configuring the data to display in the interface and define how the navigation will be within the system. The configuration of the components is based on a first model which represents the data that will be managed by the application. This methodology is based on UML (Unified Modeling Language) and is defined by an extension conservative of said language specified in a UML profile and a series of restrictions. To support the modeling methodology, a tool that allows modeling and transformations between models that are necessary to be able to generate the 100% functional source code of a app