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Because of more demanding mechanical properties in sheet steel products in the automotive industry, the use of multi-phase steels, capable of complying with those mechanical requirements, has been growing along the last decades. The non-destructive characterization of these steel grades, therefore, has become an active research line worldwide. In the present work, the magnetic characterization by magnetic hysteresis BH loops of various strip samples of industrially cold rolled and annealed DP800 (dual phase) and CP800 (complex phase) steels at several positions with varying processing temperatures in the coil length has been performed. In addition, a detailed EBSD characterization of the samples has allowed determining the fraction of the various microconstituents, namely, ferrite, bainite, martensite and retained austenite. Finally, the mechanical characterization has been done through hardness and tensile tests on all the samples. All the results regarding these three aspects have been analysed carefully to extract likely relationships among them. Clear one-to-one linear correlations have been found between all these features, even though large variations in mechanical/magnetic properties and microstructures have been attained. Specifically, for volume fractions of bainite approximately between 15% to 75%, the yield and tensile strengths show a linear correlation with the coercive field, Hc. Thus, the coercive field may be a candidate to become a parameter for the prediction of the mechanical properties if a previous calibration is performed on these steel grades with multi-phase microstructures.

On-line non-destructive magnetic monitoring (NDM) techniques are relevant to evaluate the quality of steels and their fluctuations during forming process. The on-line monitoring faces different issues. Due to magneto-mechanical coupling, stress that may be applied during NDM may have a strong effect on the magnetic behavior that may lead to erroneous estimations of the microstructure quality of the material. The multiaxial character of the stress state is another strong issue. In this communication, some new results showing the effect of a uniaxial and biaxial stress on the magnetic behavior of 3 grades of hot-rolled steels are presented (from low carbon steel to AHSS).

Weight savings in mobility and transport are mandatory in order to reduce CO 2 emissions and energy consumption. The steel industry offers weight saving solutions by a growing portfolio of Advanced High Strength Steel (AHSS) products. AHSS owe their strength to their largely refined and complex microstructures, containing multiple metallurgical phases. Optimal control of the thermo-mechanical processing of AHSS requires inline sensors for real-time monitoring of evolution and consistency of microstructure and material properties. To coordinate and accelerate European development activities in this domain, the project ”Online Microstructure Analytics (OMA)” was established in 2019, constituting of a consortium of 14 specialised research organisations. The EU-funded OMA project, with a total budget exceeding 6 MEU, focuses on inline sensing techniques to monitor the consistency and homogeneity of microstructure, texture and mechanical properties for automotive steels and in particular for AHSS.

Análisis de los impactos del turismo y de los eventos extremos para la determinación de áreas de estrés en los centros históricos de San Juan y Ponce, Puerto Rico. Universidad Nacional de Educación a Distancia. Director: Manuel Antonio Zárate Martín. Fecha: 10 de julio 2018.

La ciudad de Ponce ha tenido un desarrollo histórico sui generis y paralelo a la ciudad capital de Puerto Rico, San Juan, atendiendo a la morfología del espacio físico-geográfico donde se encuentra la misma. Toda la información recopilada y levantada para el presente artículo proviene del proyecto de investigación de Tesis de Doctorado sobre impactos causados por el turismo en las ciudades históricas de Ponce y San Juan e impactos causados en estos espacios por los eventos meteorológicos extremos. Las ciudades contemporáneas son una yuxtaposición entre lo contemporáneo y lo antiguo, entre la modernidad y la tradicionalidad, una realidad donde se superponen paisajes que responden a modelos urbanísticos distintos. Los espacios urbanos son un arreglo que varía en dependencia de la cultura y de la época, las ciudades están elaboradas y reelaboradas a partir de los que se aprecia y de cómo se aprecia al contemplar un espacio determinado, es una recreación de la realidad condicionada por la apreciación estética, las vivencias, el modo de vida o las carencias que se tengan en un momento determinado. El centro histórico de Ponce es un subsistema dentro de la ciudad, es la representación orgánica y completa de los subsistemas que la constituyen, es este el motivo del porqué analizando el crecimiento histórico desde todos los puntos de vista (desarrollo urbano, movilidad, comercio, espacios públicos, arquitectura), se puede descubrir el valor patrimonial intrínseco que posee, e incluye todas las propiedades comprendidas dentro del límite de la misma, lo que garantiza la morfología y la imagen urbana de dicha zona, añadiéndole el sector de la Playa y la Avenida de Hostos que une ambos centros urbanos. Ponce y su centro histórico han evolucionado y debe seguir evolucionando si quieren sobrevivir. La simbiosis de lo histórico con lo contemporáneo debe ser algo natural y no impostado, el centro histórico, así como los subsistemas que lo componen, debe ser aceptado como parte integral de la ciudad y no pretender manejarlo y entenderlo como un ente aislado. Su personalidad la tiene a partir de sus integralidad con el área metropolitana que lo contiene, y ver lo histórico y lo contemporáneo aisladamente siempre será en detrimento de la ciudad como un todo único e indivisible. The city of Ponce has had a historical development sui generis and parallel to the capital city of Puerto Rico, San Juan, attending to the morphology of the physical-geographic space where it is located. All the information gathered and raised for the present article comes from the project of investigation of Doctorate Thesis on impacts caused by the tourism in the historical cities of Ponce and San Juan and impacts caused in these spaces by the extreme meteorological events. Contemporary cities are a juxtaposition between the modern and the ancient, between modernity and tradition, a reality that overlaps landscapes that correspond to different urban models. Urban spaces are an arrangement that varies depending on culture and time, cities are re-elaborated from how it is appreciated when contemplating a certain space, is a recreation of reality conditioned by Aesthetic appreciation, experiences, mode of life or the shortcomings they have at any given time. The historical center of Ponce is a subsystem within the city, it is the organic and complete representation of the subsystems that constitute it, and so historical growth is analyzed from all points of view (urbanism, mobility, commerce, public spaces, Architecture). It is possible to discover the intrinsic heritage value that it possesses, which guarantees the morphology and the urban image of that area, adding the sector of the Beach and the Avenue of Hostos that unites both urban centers. Ponce and its historical center have evolved and should continue to evolve if they want to survive. The symbiosis between the historical and the contemporary must be natural and not imposed, the historical center, as well as the subsystems that compose it, must be accepted as an integral part of the city and not try to manage it and understand it as something isolated. Its personality has it from its integrality with the metropolitan area that contains it, and seeing the historical and the contemporary in isolation will always be to the detriment of the city as a single and indivisible territory.

Direct exploitation made up one of the exploitation forms of the Land lords territorial properties in medieval Europe. Throughout the central centuries of this period, this direct exploitation experimented a reduction that accelerated in the 14th Century. However, direct exploitation did not totally disappear. This process is also evident in the Duero river basin, a space in which we see an example of a Cluniac Benedictine seigniory that is defined by the large amount of information concerning it.

En la presente comunicación pretendemos abordar el tema de la pervivencia de la Historia Antigua como fuente iconográfica para el arte europeo de la Edad Moderna (el siglo XVII en nuestro caso). En una primera parte, analizaremos el ritual de la deuotio, contextualizándolo dentro de la religión romana republicana. A partir de las fuentes literarias prestaremos especial atención al estudio de la deuotio de Decio Mus. El siguiente paso será poner lo anterior en relación con Rubens y su ciclo dedicado a la deuotio de Decio Mus, intentando explicar qué motivo la elección del tema (comitente y destino de la obra), cuál de las fuentes fue la que inspiró a Rubens y qué elementos iconográficos fueron empleados para dar forma al ritual en las diferente escenas que componen el ciclo.

En esta comunicación se pretende hacer un estudio sistemático de lasfuentes literarias y bibliográficas que nos relatan o enumeran los prodigia para extraerlos y elaborar una base de datos. A partir de su elaboración, se hará un análisis estadístico que nos permita ver hasta qué punto la metodología estadística es aplicable y útil para la Historia Antigua, especialmente en la Roma republicana. Con los resultados del análisis estadístico se pretenderá aclarar, si es realmente posible, aspectos relativos a la posible implicación política de los prodigia, el papel de los sacerdocios públicos ante estos eventos y a la repercusión que todo ello pudo tener en la sociedad. La información estadística obtenida se presenta deforma clara y accesible, sin perderse en cifras y fórmulas que sólo nos apartarían de la investigación que deseamos llevar a cabo.

RESUMEN: Dentro de la línea que se prevé para este número de la revista, dedicado a la Historia de la Infancia, nuestro estudio pretende ser una elaboración de síntesis. Es un intento de encontrar unidad a algunos documentos dispersos que han ido apareciendo sobre el tema, en una tarea de localización y ordenación aún inacabada. Primero fue el librito de E. PEDRERO CABALLERO, en segundo lugar hallamos el trabajo que sirvió de Tesis Doctoral a J. MORROS SARDA, y, finalmente, encontramos unos documentos manuscritos pertenecientes al malogrado Inspector de Primera Enseñanza R. ALVAREZ y otros que hacen referencia a los «registros paidométricos».

Partindo da experiência de adaptar um programa de ensino de espanhol para a TV Cultura de São Paulo, programa especialmente orientado para as variações da língua falada na América, o texto desenvolve o conceito de metáfora como instrumento para enfrentar a enorme variação da língua e também compreender a complexidade implicada no processo de aquisição de uma língua estrangeira.

The authors have investigated the assumption that alcohol increases iron absorption. Using the whole body counter technique, they show that iron absorption is lowered significantly by addition to the test dose of either normal or dealcoholized whisky, but that there is no difference between these two latter groups. Wine has a similar effect. The use of ethanol added to a test meal demonstrates that it is organic iron, and not the inorganic form, whose absorption is diminished by alcohol.

The influence of chronic alcohol ingestion and artificially induced folic acid deficiency on iron absorption has been measured in rabbits by whole body counter. Results show that chronic alcohol ingestion does not modify iron absorption. Folic acid deficiency increases iron absorption by two probable mechanisms: first by increased plasma iron turnover (PIT), which parallels ineffective erythropoiesis, and second by a probable direct effect on the intestinal mucous membranes. This second mechanism appears to be independent of PIT: concomitant deficiency of folic acid and alcohol ingestion produces an increase in iron absorption without modification of PIT. Experience with drugs inhibiting protein synthesis suggests that this increase may be mediated by decreased protein synthesis.

An immunofluorescent technique using Crithidia luciliae (CL) has been developed to detect antibodies against native DNA, type them and determine their complement-fixing capacity. CL possess a kinetoplast containing double-stranded DNA that is not bound to histones: they are therefore a substrate well suited to the determination of antibodies against native DNA. When compared with a radioimmunoassay the technique displayed the same specificity and sensitivity. However, the correlation between clinical symptoms of SLE and anti-DNA antibody titer was better with the CL method than with radioimmunoassay. Determination of complement-fixing capacity and the type of immunoglobulins did not provide useful information. The CL method proved to be reliable, rapid and cheap.