A general framework for continuum damage models. II. Integration algorithms, with applications to the numerical simulation of porous metals

In this paper, we develop numerical algorithms for the integration of the continuum plastic damage models formulated in the general framework identified in Part I of this work. More specifically, we focus our attention on a particular plastic damage model of porous metals, involving a classical von Mises yield criterion coupled with a pressure dependent damage surface to model the nucleation and growth of voids in the metallic matrix. Unilateral damage leading to a sudden change of stiffness in the material's response due to the closing/opening of these voids is also incorporated through the imposition of the unilateral constraint of a positive void fraction, thus, illustrating the clear physical significance added by this framework in the resulting constitutive models. The proposed integration algorithms fully use the modularity of the identified framework, leading in this way to independent integration algorithms for the elastoplastic part and each damage mechanism. Remarkably, all these individual integration schemes share the same formal structure as the classical return mapping algorithms employed in the numerical integration of elastoplastic models, namely an operator split structure consisting of a trial state and the return map imposing the plastic and damage consistency, respectively. A Newton iterative scheme imposes the equilibrium (equal stresses) among the different mechanisms of the response of the material. This modular structure allows to obtain the closed-form consistent linearization, involving in a simple form the algorithmic consistent tangents corresponding to each independent mechanism, thus resulting in a very modular and efficient computational implementation. The performance of the proposed algorithms is illustrated in several representative numerical simulations

On the formulation of closest-point projection algorithms in elastoplasticity. Part I: The variational structure.

Report UCB/SEMM 2000-01 - Dept. of Civil Engineering - University of California at Berkeley, USAWe present in this paper the characterization of the variational structure behind the discrete equa- tions defining the closest-point projection approximation in elastoplasticity. Rate-independent and viscoplastic formulations are considered in the infinitesimal and the finite deformation range, the later in the context of isotropic finite strain multiplicative plasticity. Primal variational prin- ciples in terms of the stresses and stress-like hardening variables are presented first, followed by the formulation of dual principles incorporating explicitly the plastic multiplier. Augmented La- grangian extensions are also presented allowing a complete regularization of the problem in the constrained rate-independent limit. The variational structure identified in this paper leads to the proper framework for the development of new improved numerical algorithms for the integration of the local constitutive equations of plasticity as it is undertaken in Part II of this work.Preprin

On the formulation of closest-point projection algorithms in elastoplasticity. Part II: Globally convergent schemes. With applications to deviatoric and pressure-dependent plastic models.

Report UCB/SEMM 2000-02 - Dept. of Civil Engineering - University of California at Berkeley, USAPreprin

Bayesian approach to urinary ESBL-producing Escherichia coli

This is a retrospective study about the prevalence of ESBL-producing Escherichia coli (EEC) in urinary specimens from patients from the Comunitat Valenciana from January 2007 to December 2008. Data were retrieved from RedMIVA, and Bayesian generalized linear mixed models were considered to study the prevalence of EEC with regard to demographical and microbiological factors. The total number of infections considered was 164,502, the amount of urinary isolates was 70,827 belonging to 49,304 different patients, and 5,161 (7.3%) of the urinary isolates were EEC. Three out of four E. coli were isolated in women (76.8%), men showed higher rates of EEC (9.7% in men vs. 6.5% in women). EEC patients were, in average, 10.8 years older, and hospitalization was more frequent (9.9% vs. 6.9%). Resistance to non-β-lactams antimicrobials was higher in EEC. The rates of ciprofloxacin and co-trimoxazol resistance in EEC were 75.5% and 52.0%, respectively, whereas it ranged between 1.4-12.4% for the rest of antimicrobials.Prior EEC infection and hospitalization were the most relevant risk factors and increased the expected EEC probability approximately 400% and 50% respectively. Other infections played an important and positive role too, Enterobacteriaceae, P. aeruginosa and other bacteria being the most relevant elements. Female gender was a protective factor and reduced the risk by approximately 25% while age was an additive risk factor. Finally, an open-access web-based software was constructed to compute the probability that an E. coli in a urinary infection be an EEC from a specific combination of risk factors. This pharmacovigilance tool should prove useful to monitor and control antimicrobial resistance spread

Changes in radiological protection and quality control in Spanish dental installations : 1996-2003

Introduction: The European Union has established specific directives concerning radiological protection which are obligatory for member States. In addition, all Spanish dental clinics with radiological equipment are required to have an annual quality control check. Objective: To analyze the effect of new European legislation on dental radiological practice in Spain and to determine whether it has resulted in lower doses being administered to patients. Material and Methods: A total of 10,171 official radiological quality control reports on Spanish dental clinics, covering 16 autonomous regions, were studied following the passing of Royal Decree 2071/1995 on quality criteria in radiodiagnostic installations. The reports, compiled by U.T.P.R Asigma S.A., a company authorised by the Nuclear Safety Council, cover the years 1996 to 2003, which has enabled us to monitor the evolution of radiological procedures in dental clinics over a seven year period. Results: According to the reports for 2003, 77.3 % of clinics complied with EU requirements, using equipment of 70 kVp, 8 mA, 1.5 mm Al filters, with a collimator length of 20 cm. However, non-compliance was detected in approximately a third (30.8%) of the equipment inspected: alterations in the kilovoltage used, exposure time, performance of the tubing, dosage, linearity/intensity of current and acoustic-luminous signal 6.86%. The mean skin dose reached 3.11 mGy for patients who received an x-ray of an upper molar, representing a decrease of 18% over the seven years studied. Conclusion: there has obviously been a general improvement in the parameters studied, but only 77.3% of the installations complied fully with official EU regulations concerning dental radiological protection

Q1311X: a novel nonsense mutation of putative ancient origin in the von Willebrand factor gene

[EN] Type 3 von Willebrand disease, a recessive autosomally inherited bleeding disorder, refers to complete deficiency of von Willebrand factor (VWF). The novel Q1311X mutation was detected in the homozygous state in four Spanish patients from two apparently unrelated families of gypsy origin. The lack of specific amplification of platelet VWF cDNA from two of the patients indicates reduced levels of mutated gene expression. The similar haplotype linked to mutated alleles suggests a common origin. On the basis of the two instabilities observed and the estimated mutation rate of the microsatellites of intron 40 of the VWF gene, we can estimate that this mutation could have arisen about 2300 years ago.We wish to thank J.M. Montoro and R. Curats for their technical assistance. This work was supported in part by F1S 99/0633.Casaña, P.; Martínez, F.; Haya, S.; Lorenzo, JI.; Espinós-Armero, CÁ.; Aznar, JA. (2000). Q1311X: a novel nonsense mutation of putative ancient origin in the von Willebrand factor gene. British Journal of Haematology. 111(2):552-555. https://doi.org/10.1046/j.1365-2141.2000.02410.x552555111

Protocolo de valorización de residuos en la fabricación de materiales de base cemento: sedimentos dragados como componente de hormigón autocompactante

[ES] La incorporación de los materiales procedentes del dragado como materia prima en la industria de la construcción es uno de los principales objetivos del sector, dada la creciente demanda de este tipo de materiales y la cada vez mayor escasez de los recursos procedentes del interior. La mayor parte de las investigaciones realizadas se han centrado en la reutilización de residuos industriales y de demolición, sin embargo, el uso de materiales procedentes de dragado no ha sido tan ampliamente estudiado y no se han encontrado protocolos para evaluar de forma sistemática su viabilidad como materia prima en la fabricación de materiales con base cemento. En este sentido, el principal objetivo de esta investigación es el diseño de un protocolo que permita evaluar la idoneidad de un residuo procedente de un puerto español como componente de un hormigón autocompactante (SCC). Para ello se realizará un completo análisis químico, mineralógico y granulométrico del sedimento y, una vez comprobada su idoneidad, el éxito de su inclusión como parte del SCC se estudiará mediante ensayos de durabilidad y de compatibilidad medioambiental. Estos ensayos mostrarán que las propiedades del SCC obtenido están de acuerdo con las esperadas para uno convencional fabricado con filler silíceo normal.Esta investigación formó parte del proyecto CLEAM CENIT patrocinado por el Centro Español de Desarrollo Tecnológico Industrial (CDTI) dentro del programa CENIT y ha sido posible gracias al apoyo económico del CDTI y A.I.E. (Asociación de Interés Económico) CLEAM-CENIT. Mención especial a DRAGADOS, que fue el responsable de la coordinación industrial de la tarea en la que se desarrolló este trabajo. Los autores también agradecen al Ministerio de Economía y Competitividad la financiación aportada por el proyecto BIA 2011-25653 '' TELEPASSCLOR '' otorgado en el marco del Plan Nacional de I + D + iRozas, F.; Castillo Talavera, A.; Martínez Sierra, I.; Castellote Armero, M. (2018). Protocolo de valorización de residuos en la fabricación de materiales de base cemento: sedimentos dragados como componente de hormigón autocompactante. En HAC 2018. V Congreso Iberoamericano de hormigón autocompactable y hormigones especiales. Editorial Universitat Politècnica de València. 291-300. https://doi.org/10.4995/HAC2018.2018.5637OCS29130

Development of the first microsatellite multiplex PCR panel for meagre (Argyrosomus regius), a commercial aquaculture species

In this study, a microsatellite-based multiplex PCR panel for meagre (Argyrosomus regius) was developed as a useful and single tool in parental assignment and population studies. Twenty-one specific and interspecific microsatellites from different aquaculture species of meagre (Argyrosomus regius), Japanese meagre (A. japonicus), red drum (Sciaenops ocellatus) and yellow meagre (Acoupa weakfish) were assessed for genetic variability, allelic range and genotype reliability. Finally, a SuperMultiplex for Argyrosomus regius (SMAr) was designed with only the best eight microsatellite markers. The panel assessment was performed using a batch of brood stock from one company and a sample of 616 offspring. It was possible to assign 95% of the offspring to a single pair of parents using the exclusion method. It is therefore considered an easy procedure, and a powerful and low-cost tool for parental assignment to support companies’ breeding programs and to exchange information between research groups.This research was funded by Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia through the project “Mejora de la competitividad del sector de la corvina a través de la selección genética (GENECOR, 21002/PI/18)” in the call for grants for projects for the development of scientific and technical research by competitive groups, included in the Regional Program for the Promotion of Scientific and Technical Research (Action Plan 2018). A.V. was funded by a pre-doctora research fellowship (20716/FPI/18. Fundación Séneca. Cofinanciado por grupo Avramar S.L. Región de Murcia (Spain)). The Avramar S.L. group provided financial support and the use of its facilities for this study

Phenotypic and genetic components for growth, morphology, and flesh-quality traits of meagre (Argyrosomus Regius) reared in tank and sea cage

Meagre (Argyrosomus regius) plays an important role in the aquaculture system, with the potential for diversification of European aquaculture, and is characterized by its fast growth rate, low feed conversion ratio, and the high quality of the product. Focusing on the relevance of meagre, the aim of the study was to analyze growth performance, fish morphology, and flesh composition phenotypically and genetically to be considered as a strategy in a breeding program. For this purpose, 633 fish were raised in two different housing systems, in sea cages or in a continental tank, and when they reached harvest size, manual growth traits, automatic morphology by the image analysis program IMAFISH_ML, and flesh chemical composition (fat, protein, moisture, and collagen percentages) were measured. The fish reared in the cages showed a higher body weight and fillet fat percentage than those in the tank. Heritabilities for growth and morphology traits, and for fillet fat percentage were medium, revealing these traits as a possible selection criterion in a breeding program. Phenotypic and genetic correlations between growth and morphology traits were positive and high. Phenotypic correlations between growth or morphology traits with fillet fat percentage were positive and medium; genetic correlations were not estimated accurately.This research was funded by Fundación Séneca-Agencia de Ciencia y Tecnología de la Región de Murcia through the project “Mejora de la competitividad del sector de la corvina a través de la selección genética” (GENECOR, 21002/PI/18) in the call for grants for projects for the development of scientific and technical research by competitive groups, included in the Regional Program for the Promotion of Scientific and Technical Research (Action Plan 2018). A.V. was funded by a pre-doctoral research fellowship (20716/FPI/18. Fundación Séneca. Cofinanciado por grupo Avramar S.L. Región de Murcia (Spain))

Vitamin C and microbial quality of minimally fresh processed pea seeds stored in modified atmosphere packaging

[SPA] Los guisantes (Pisum sativum L.) son una fuente importante de proteínas, carbohidratos, vitaminas y minerales. Debido a su alta tasa respiratoria, se deterioran rápidamente. Existe muy poca información sobre las condiciones óptimas de almacenamiento de semillas de guisantes inmaduras, pese a su conveniencia para utilizarse como producto mínimamente procesado. El objetivo de este trabajo fue analizar la calidad microbiológica y los cambios en la vitamina C de semillas inmaduras almacenadas a 1 y 4 °C en atmósferas modificadas (PPO 25 μm). Las semillas se lavaron con hipoclorito sódico (HS) (100 ppm, pH 6,5) o con clorito sódico acidificado (CSA) (300 ppm, pH 1,8). Después de 14 días, la atmósfera alcanzada fue de 8 kPa CO2/12 kPa O2 y 11 kPa CO2/10 kPa O2 a 1 y 4 °C, respectivamente. El crecimiento de mesófilos se redujo con la conservación a 1 °C, independientemente del desinfectante utilizado, mientras que las enterobacterias decrecieron en todos los tratamientos. La vitamina C disminuyó desde ≅ 700 mg kg-1 pf hasta 250 o 450 mg kg-1 pf, para HS y CSA respectivamente. El lavado con CSA y almacenado a 1 °C ó 4 °C proporcionó un producto de buena calidad después de 14 días. [ENG] Peas (Pisum sativum L.) are an important source of protein, carbohydrates, vitamins and minerals. Due to their very high respiration rate, loss of quality is fast. There is very little information about the optimal storage conditions for immature pea seeds, which are well adapted to be prepared as a minimally processed product. The objective of this research was to analyze the microbial quality and changes in vitamin C of fresh pea seeds stored at 1 and 4 °C in modified atmosphere packaging (MAP) (OPP 25 μm). Seeds were disinfected with sodium hypochlorite (HS) (100 ppm, pH 6.5) or with acidified sodium chlorite (CSA) (300 ppm, pH 1.8). After 14 days, the atmospheres within the packages were 8 kPa CO2/12 kPa O2 and 11 kPa CO2/10 kPa O2 at 1 and 4 °C, respectively. Mesophilic growth was reduced when samples were stored at 1 °C, regardless of the disinfectant, while enterobacteria were reduced in all the treatments. Vitamin C decreased from ≅ 700 mg kg-1 fw to 250 or 450 mg kg-1 fw, for HS and CSA respectively. Disinfection with CSA and storage at 1 or 4 °C allowed to obtain a good quality product after 14 days.Al Proyecto EUROLEGUME (EU FP7 Research Project No. 613781) financiado por fondos de la Unión Europea dentro del 7º Programa Marco de Investigación, Desarrollo Tecnológico y Diseminación