On the use of the combined FMC-ASED criterion for fracture prediction of notched specimens with nonlinear behavior

ABSTRACT: The Averaged Strain Energy Density (ASED) criterion has been widely used for the prediction of fracture conditions in a number of materials containing notch type defects, similarly to other well-known methodologies such as the Theory of Critical Distances (TCD). This criterion is linear-elastic, so the results obtained in linear-elastic materials have been accurate. However, as soon as the material behavior becomes nonlinear, the resulting accuracy decreases. With the aim of using linear-elastic simple methods (such as the ASED criterion) in nonlinear materials, several attempts have been made to convert a physically nonlinear behavior into an equivalent linear behavior. Thus, when the tensile behavior in plain specimens reveals nonlinearity, but the fracture behavior in the presence of defects is linear, the Equivalent Material Concept (EMC) has been successfully validated (EMC-ASED criterion). However, there are situations in which the nonlinear behavior takes place in both tensile and fracture behaviors, and the EMC-ASED criterion loses accuracy and requires further evolution. At this point, the Fictitious Material Concept allows the analysis of nonlinear materials (at both tensile and fracture conditions) to be performed with significant accuracy. In this context, this article provides the prediction of fracture loads in single edge notched bending (SENB) specimens made of short glass fiber reinforced polyamide 6 (SGFR-PA6, 10 wt.%) containing U-notches and different levels of moisture content. The predictions are obtained through the combination of the FMC and the ASED criterion (FMC-ASED combined criterion). The results are significantly more accurate than those obtained through the ASED and the EMC-ASED criteria, but less accurate than those used when combining the FMC with the TCD.The authors of this work wish to extend their gratitude to the Spanish Ministry of Science and Innovation for the financial support of the Project MAT2014-58443-P: “Análisis del comportamiento en fractura de componentes estructurales con defectos en condiciones debajo confinamiento tensional”, on the results of which this paper is based

Considerations on the joint recovery of the monument and its environment: The town walls of albarracÍn (Spain)

The city walls of Albarracín (Teruel) show an exemplary trajectory of restoration and conservation works, thanks to a fifty year-long trajectory of interventions carried out by different architects. The last of these projects, promoted by the City Council and driven by Fundación Santa María de Albarracín, was drafted in 2019 and involved the restoration of the southern end of the wall. For the first time, this project has addressed the recovery of the monument and its surroundings in a joint effort that bets on a global vision for the city's public space system. The keys to this binomial are based on the following premises: a well-coordinated monument-environment relationship, the emphasis on a conservative approach to the restoration works, the promotion of public use and the dignification of the space in a coherent way with its context. The joint treatment of the building and its environment goes far beyond an aesthetic or functional issue - which may have been achieved through independent projects - and verifies the criteria adopted for both dimensions of the project: minimal intervention, distinguishability, preservation of the authenticity, reversibility, compatibility, character, readability and sustainability. In general, this approach reduces the risks of unilateral, partial or limiting visions ending in the loss of heritage value and embraces the understanding of the immediate environment as an inseparable extension of the monument itself

Preliminary results from characterization of the Iberian Peninsula sturgeon based on analysis of the mtDNA cytochrome b

Historically, the Atlantic sturgeon Acipenser sturio L., 1758 was considered the only sturgeon species that inhabited rivers of the Iberian Peninsula. Nevertheless, in a recent paper, Garrido- Ramos et al. (1997) identified specimen EBD 8174 (museum collection of the Doñana Biological Station, Spain), from the Guadalquivir River, as the Adriatic sturgeon Acipenser naccarii Bonaparte, 1836, suggesting that both A. sturio and A. naccarii could be native to Spain. To test this theory, we compared partial mitochondrial cytochrome b (cyt b) gene sequences obtained from museum specimens of A. sturio that originated from the Iberian Peninsula, the Adriatic and the North Sea, as well as from live individuals of the Gironde River population in France. Specimens of A. naccarii and of the Siberian sturgeon Acipenser baerii Brandt, 1869 from fish farms were also included in the study. DNA from museum specimens was successfully amplified using the protocol of France and Kocher (1996) for DNA extraction from formalin-fixed and ethanol-preserved samples. Phylogenetic analysis was performed on partial cyt b gene sequences (over 402-bp and 245-bp). We identified specimen EBD 8174 as A. sturio, confirming the opinion that A. sturio is the only sturgeon species of the Iberian Peninsula. Further molecular analyses of museum specimens are needed for a description of the historical intraspecies genetic variation within A. sturio. This information is crucial for any future recovery plan for this species. Our comparison also showed interspecies sequence divergence ranging from 6.91% (A. sturio/A. naccarii) to 7.43% (A. sturio/A. baerii).Históricamente, el esturión atlántico Acipenser sturio L., 1758 ha sido considerado la única especie de esturión que vive en los ríos de la península Ibérica, siendo así demostrado por múltiples estudios morfológicos recientes. Sin embargo, un trabajo reciente identificó el ejemplar del río Guadalquivir EBD 8174 como Acipenser naccarii Bonaparte, 1836, sugiriendo que ambas especies de esturión podrían ser nativas de España. Para comprobar esta nueva teoría, se han analizado las secuencias del gen citocromo b mitocondrial en muestras de esturión atlántico preservadas en varios museos procedentes de la península Ibérica, el mar Adriático y el mar del Norte, así como material fresco del río Garona. Además, se han estudiado con fines comparativos varias muestras de A. naccarii y Acipenser baerii Brandt, 1869 procedentes de piscifactorías. Las muestras de museos fueron amplificadas con éxito usando un protocolo específico utilizado para material fijado en formol y preservado en alcohol. La muestra de esturión de España (EBD 8174) fue identificada como A. sturio. Este resulta do confirma que A. sturio es la única especie de esturión en la península Ibérica. De cualquier manera, antes de abordar los planes de recuperación, sería necesario realizar análisis moleculares complementarios para describir las posibles variaciones genéticas existentes entre poblaciones. La comparación de las secuencias de citocromo b de A. sturio con A. naccarii y A. baerii mostró valores de divergencia de 6,91% y 7,43% respectivamente.Instituto Español de Oceanografí

Scientific, Technical and Economic Committee for Fisheries (STECF) - Fisheries Dependent Information – FDI (STECF-20-10)

Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. The STECF reviewed the report of the EWG on Fisheries-dependent Information during its winter 2020 virtual plenary meeting.E

Detección de QTLs asociados a la resistencia al Virus del Enanismo Amarillo de las Cucurbitáceas en la línea de melón TGR-1551 (abstract)

La línea de melón TGR-1551 procedente de Zimbabwe tiene una alta resistencia al Virus del enanismo amarillo de las cucurbitáceas (CSYDV). A partir de un cruce original entre TGR-1551 y el cultivar español 'Bola de Oro' se ha obtenido una población RIL (F/Fg) en la que se ha evaluado la resistencia a dicho virus. Se han realizado cuatro repeticiones, Primavera 1 (inoculación con caja pinza), Primavera 2 (inoculación por infestación masiva con mosca virulenta durante 72 horas), Primavera 3 (inoculación con caja pinza) y verano (inoculación por infestación masiva con mosca virulenta durante todo el experimento), en las que se han evaluado los síntomas de la enfermedad; en la de verano se ha realizado además una valoración de la presencia del virus en la planta mediante RT-PCR a las cuatro semanas de realizada la infestación. En este trabajo se presentan los datos preliminares sobre la identificación de QTLs relacionados con dicha resistencia utilizando para ello un mapa de SNPs generado por GBS a partir de 125 RILs de este crucePublishe

El sistema dunar de Valdevaqueros: evolución histórica y alternativas de gestión

ResumenLa duna de Valdevaqueros, situada al sur de España, presenta elevadas tasas de migración asociadas a los fuertes vientos de levante que soplan en el estrecho de Gibraltar. Ubicada en una zona de elevada presión humana, su dinámica ha entrado en conflicto con los usos del suelo, provocando una notable repercusión desde los puntos de vista científico y técnico, pero también desde una perspectiva mediática y social. Este trabajo se centra en el análisis de la evolución histórica del sistema dunar desde principios del sigloxx mediante el estudio del material cartográfico y fotográfico disponible, analizando los diferentes estadios que se han sucedido, los mecanismos y agentes naturales que gobiernan su comportamiento, así como las repercusiones derivadas de las diferentes actuaciones en la zona. La intervención sobre el corredor dunar iniciada a principios de 1940 ha condicionado los procesos y la evolución de toda la unidad fisiográfica. La morfodinámica dunar actual se explica por el balance neto de sedimentos. El sistema recibe arena disponible en la zona sumergida transportada por el oleaje de poniente que se acumula en la playa y ensancha la playa seca. El viento de levante erosiona el sedimento en la playa seca y lo transporta hacia la duna. Se estima que en los últimos 50años la playa seca (fetch) ha crecido, en promedio, más de 150m, y que el sistema almacena arena suficiente para mantener estos mecanismos de transporte durante las próximas décadas. A partir de estos resultados, se plantean y analizan diferentes vías de actuación para la gestión integral de la zona.AbstractValdevaqueros dune, in the south of Spain, exhibits high migration rates associated with strong easterly winds in the Strait of Gibraltar. The system is located in an area of high human pressure and its dynamic has collided with land use causing a significant impact from scientific and technical points of view but also from a media and social perspective. This paper focuses on the historical evolution of the dune system since the beginning of the 20th century by studying the available cartographic and photographic material, analyzing the different phases, the mechanisms and natural agents governing the dune behaviour and the implications arising from the activities in the area. The intervention on the dune corridor started in the early 1940s and has conditioned the evolution of all the processes in the physiographic region. The current dune morphodynamics is explained by the sediment budget. The system receives sand from the submerged zone, which is transported by westerly wind waves. This material accumulates and widens the dry beach. The easterly winds erode the sediment in the dry beach and transports it to the dune. In the last fifty years, the dry beach (fetch) has grown, on average, over 150m and the system stores enough sand to sustain these transport mechanisms for decades. From these results, we discuss different alternatives for the integrated management of the area

New iterative method to obtain the softening curve in concrete.

Abstract An original procedure to determine the softening curve in concrete has been proposed by the authors. This inverse method combines experimental results, finite element simulations and an iterative algorithm to adjust the experimental data. The end product of the process is a softening curve that allows us to very accurately reproduce the experimental curves. The proposed method calculates the fracture energy from the cohesive softening curve model, which in turn is iteratively determined by adjusting experimental load-displacement data of three-point bending tests. The procedure has been successfully applied to two conventional concretes

Targeted Community Merging provides an efficient comparison between collaboration clusters and departmental partitions

Community detection theory is vital for the structural analysis of many types of complex networks, especially for human-like collaboration networks. In this work, we present a new community detection algorithm, the Targeted Community Merging algorithm, based on the well-known Girvan–Newman algorithm, which allows obtaining community partitions with high values of modularity and a small number of communities. We then perform an analysis and comparison between the departmental and community structure of scientific collaboration networks within the University of Zaragoza. Thus, we draw valuable conclusions from the inter- and intra-departmental collaboration structure that could be useful to take decisions on an eventual departmental restructuring

Electronic Report Generation Web Service evaluated within a Telemedicine System

This work presents a generic tool based on a client-server architecture that generates electronic reports helping the evaluation process of any information system. For the specific evaluation of telemedicine systems the defined reports cover four dimensions: auditory of the system; evolution of clinical protocols; results from the questionnaires for user acceptance and quality of life; and surveillance of clinical variables. The use of a Web Service approach allows multiplatform use of the developed electronic report service and the modularity followed in the implementation enables easy system evolution and scalability

Las células presentadoras de antígeno y su papel en el síndrome reproductivo y respiratorio porcino

Las células presentadoras de antígeno son aquellas células encargadas de capturar, procesar y presentar antígenos con la finalidad de lograr una respuesta inmune efectiva por parte del organismo. Su papel, como centinelas, es crucial durante el transcurso de diversas enfermedades infecciosas. El estudio de estas células tras la infección con el virus del Síndrome Reproductivo y Respiratorio Porcino nos da información para abordar nuevas estrategias de control frente a esta enfermedad.Antigen presenting cells are able to capture, process and present antigens in order to develop an effective immune response. The role of these cells during infectious diseases is crucial to control the disease. Thus, the study of these cells after the infection with Porcine Reproductive and Respiratory Syndrome Virus gives us useful information on how to control this disease