Life cycle cost optimisation in highway concrete bridges management

This study presents a life cycle cost prediction and cost minimisation methodology for a set of highway concrete bridges, during a medium or a long period of time, in order to facilitate the decision process of the structure management. This methodology takes into consideration bridge intervention costs in addition with some Markov matrices degradation model. It applies a genetic algorithm in order to identify the optimised intervention plan, considering the available budget and the desired minimum performance level. Some Portuguese direct and indirect cost parameters, associated with different types of interventions during bridges lifetime, are presented. Finally, a probabilistic sensitivity analysis is carried out using Monte Carlo simulations.5A1D-90C1-54FE | Joana Maria Martins Rosa Maia de Oliveira Almeidainfo:eu-repo/semantics/publishedVersio

Drosophila Adaptation to Viral Infection through Defensive Symbiont Evolution

Microbial symbionts can modulate host interactions with biotic and abiotic factors. Such interactions may affect the evolutionary trajectories of both host and symbiont. Wolbachia protects Drosophila melanogaster against several viral infections and the strength of the protection varies between variants of this endosymbiont. Since Wolbachia is maternally transmitted, its fitness depends on the fitness of its host. Therefore, Wolbachia populations may be under selection when Drosophila is subjected to viral infection. Here we show that in D. melanogaster populations selected for increased survival upon infection with Drosophila C virus there is a strong selection coefficient for specific Wolbachia variants, leading to their fixation. Flies carrying these selected Wolbachia variants have higher survival and fertility upon viral infection when compared to flies with the other variants. These findings demonstrate how the interaction of a host with pathogens shapes the genetic composition of symbiont populations. Furthermore, host adaptation can result from the evolution of its symbionts, with host and symbiont functioning as a single evolutionary unit.Austrian Science Funds grant: (FWF P27630)

Análise numérica da propagação de ondas sobre a plataforma continental interna e antepraia da costa sul do Brasil: de Torres a Mostardas

The shoreface and the inner shelf along the northern and the central coast of Rio Grande do Sul (RS) state, Brazil, between Torres and Mostardas, although displaying a homogeneous bottom relief show variations in slope and width. In the northern sector, between Torres and Pinhal, the inner shelf is wide, while the shoreface is narrow. Towards the south, these patterns are just the opposite. In this study, a model based on the parabolic approximation of the mild slope equation, REF/DIF.1, is used to simulate the wave propagation in this region. Wave refraction diagrams based on the predominant wave climate show a dominant and invariable divergent pattern for wave incidence from 90° to 135°. Numerical analyses of changes in wave energy, regarding differences in width and slope using a bottom friction coefficient fw = 0.01 in the different coastal sectors, show little influence of the bottom friction over the wave transformation processes. In general, a friction coefficient fw = 0.2 shows that wave energy reduction due to bottom friction over the wider shoreface south of Pinhal by comparison with the sector to the north is compensated by its shorter inner shelf width. The analyses show that lateral gradients of wave energy along the 10 m isobaths regarding the morphological differences between the two sectors are negligible.A plataforma continental interna e a antepraia ao longo do litoral norte e médio do estado do Rio Grande do Sul (RS), Brasil, entre Torres e Mostardas, têm o relevo do fundo homogêneo, mas apresentam variações de inclinação e largura. No setor norte, entre Torres e Pinhal, a plataforma interna é mais larga, enquanto a largura de antepraia é mais estreita. Por outro lado, o oposto ocorre ao Sul de Pinhal. Este trabalho analisa numericamente a propagação de ondas nesta região através do REF/DIF 1, modelo que adota a aproximação parabólica da equação de declive suave. Os diagramas de refração de ondas, baseados em um clima de onda predominante, indicam que o padrão dominante é o divergente para ondas incidentes de 90° a 135°. Análises numéricas das variações de energia de ondas, investigando a influência das variações da largura da plataforma interna e da largura de antepraia, e da fricção com o fundo considerando um coeficiente de atrito fw = 0,01, revelam a pouca influência do atrito com o fundo sobre a transformação das ondas. Adotando-se um coeficiente de atrito fw = 0,2, constata-se, de forma geral, que a influência do aumento da largura da antepraia do sul de Pinhal para o norte no atrito com o fundo é compensada pela influência da diminuição da largura da plataforma continental interna. As análises mostram que os gradientes laterais da energia da onda ao longo da isobatimétrica de 10 m, mesmo considerando as diferenças morfológicas entre os dois setores, são desprezíveis

Modelling of friction stir welding and its influence on the structural behaviour of aluminium stiffened panels

This work deals with the modelling and numerical simulation of aluminium stiffened panels, assembled by means of friction stir welding (FSW) operations, and subjected to compressive loads that can catastrophically induce buckling (global or local) unstable modes and, subsequently, overall failure. Due to their geometrical complexity, added to localized thermo-mechanical effects that typically come from joining by welding, approximation methods such as the Finite Element Method are typically used in such nonlinear analyses, having proved to be useful to designers focused on the prediction of the behaviour (before and post buckling) of such structures. Being grounded on previous contributions from the authors, the present paper aims to bring a number of innovative aspects to the current state of the art by considering in the developed models the simultaneous influence of residual stress fields, material softening effects and geometrical imperfections. Doing so, it is possible to infer about the singular and combined influence of these effects in the overall structural performance of stiffened panels, building up a useful and comprehensive methodology for design stages

Numerical simulation of the buckling behaviour of stiffened panels: Benchmarks for assessment of distinct modelling strategies

This work deals with the effective modelling and simulation of the behavior of stiffened panels, when subjected to compressive (buckling) loads. Within the Finite Element Method, two numerical strategies are compared, namely the Riks method and the displacement incremental control method, including damping effects. The capabilities and limitations of both approaches are explored for two distinct benchmarks: a panel with a blade stiffener, and a panel with a T shaped stiffener. In both cases, material (plasticity) and geometrical (large displacements) nonlinearities are considered, together with a modelling strategy based on shell elements. Following previous works of the authors, each panel accounts for initial geometric imperfections coming from friction stir welding joining operations. The paper shows a number of considerations that must be undertaken when choosing between one of the two modelling strategies. Both benchmarks involve a number of challenges from the point of view of modelling unstable structural behaviors, and therefore the proposed benchmarks can represent a valid set of case studies in the understanding of the capabilities of current numerical simulation codes

In vitro genotoxicity assessment of a dextrin-based hydrogel for biomedical applications

[Excerpt] Hydrogels are three dimensional, crosslinked networks of hydrophilic polymers swollen with a large amount of water or biological fluids. Dextrin, a low-molecularweight carbohydrate composed by glucose residues, has been used to develop a novel fully resorbable and injectable hydrogel for biomedical applications. Dextrin was firstly oxidized (ODEX) to introduce aldehyde groups which then reticulate with adipic acid dihydrazide (ADH), forming the dextrin-based hydrogel (HG) [1]. The cross-linked ODEX is an in situ forming hydrogel, which displays a three-dimensional network with inter-connective pores, and is able to incorporate nanogels, cells and biomolecules for biomedical applications [1-3]. [...]Isabel Pereira was supported by the grant SFRH/BD/ 90066/2012 from FCT. We thank FEDER and NORTE 2020 through the project nº 003262 titled “iBONE therapies: advanced solutions for bone regeneration”. We also thank the funding from FCT (UID/BIO/044469/2013) and from FEDER through COMPETE 2020 (POCI-01-0145-FEDER-006684).info:eu-repo/semantics/publishedVersio

Prediction of Friction Stir Welding effects on AA2024-T3 plates and stiffened panels using a shell-based finite element model

Manufacturing-induced effects significantly affect in-service behaviour of welded structures, such as integrally stiffened panels for aeronautic applications. Being a complex phenomenon with several variables involved, the assessment of the effects coming from welding usually relies on numerical simulations. Here, a novel shell-based finite element model is proposed to accurately simulate the transient thermal fields and stress-strain distributions resulting from friction stir welding (FSW) processes. The capability of the model to predict (i) residual stresses, (ii) material softening and (iii) geometric distortion of the welded parts is assessed by the modelling and simulation of FSW applied on aluminium integrally stiffened panels

Case report of a metachronous multiple tumor: Mantle cell lymphoma in the orbital region associated with epithelial malignancies at other sites

Here we report the case of a 73-year-old man who was diagnosed with metachronous, multiple primary tumors with non-Hodgkin B-cell mantle cell lymphoma involving the orbit on the basis of biopsy and immunohistochemistry in 2012. The patient had been diagnosed with non-Hodgkin small cell lymphoma and basal cell skin carcinoma in 2010 and intestinal adenocarcinoma with metastasis to the regional lymph nodes in 2011, thus representing a typical case of metachronous, multiple primary tumors. Mantle cell lymphoma is a rare disease and its prognosis is quite poor, particularly when it is associated with other metachronous malignancies. Therefore, physicians should consider mantle cell lymphoma as a differential diagnosis for neoplasms of the orbit

Have the cake and eat it: optimizing nondestructive DNA metabarcoding of macroinvertebrate samples for freshwater biomonitoring

Resource ArticleDNA metabarcoding can contribute to improving cost‐effectiveness and accuracy of biological assessments of aquatic ecosystems, but significant optimization and standardization efforts are still required to mainstream its application into biomonitoring programmes. In assessments based on freshwater macroinvertebrates, a key challenge is that DNA is often extracted from cleaned, sorted and homogenized bulk samples, which is time‐consuming and may be incompatible with sample preservation requirements of regulatory agencies. Here, we optimize and evaluate metabarcoding procedures based on DNA recovered from 96% ethanol used to preserve field samples and thus including potential PCR inhibitors and nontarget organisms. We sampled macroinvertebrates at five sites and subsampled the preservative ethanol at 1 to 14 days thereafter. DNA was extracted using column‐based enzymatic (TISSUE) or mechanic (SOIL) protocols, or with a new magnetic‐based enzymatic protocol (BEAD), and a 313‐bp COI fragment was amplified. Metabarcoding detected at least 200 macroinvertebrate taxa, including most taxa detected through morphology and for which there was a reference barcode. Better results were obtained with BEAD than SOIL or TISSUE, and with subsamples taken 7–14 than 1–7 days after sampling, in terms of DNA concentration and integrity, taxa diversity and matching between metabarcoding and morphology. Most variation in community composition was explained by differences among sites, with small but significant contributions of subsampling day and extraction method, and negligible contributions of extraction and PCR replication. Our methods enhance reliability of preservative ethanol as a potential source of DNA for macroinvertebrate metabarcoding, with a strong potential application in freshwater biomonitoringinfo:eu-repo/semantics/publishedVersio

Revitalization of a small textile factory from the XIX century

The cultural heritage of a region is a priceless asset in creating an identity and the definition of a unique future. Craftsmanship particularly that concerned with textile has been a constant tradition in the Minho region. Such environment has led to the creation of a textile industrial museum: Museum of Textile Industry of Bacia do Ave. Such heritage has been central to Father Airosa since the early days when, at the Instituto Monsenhor Airosa, by the end of 19th century, he decided to use the work in weaving as route for his rehabilitation project with girls from street. Even today his project endures and works as a school to form young girls that need help due to social reasons. This paper describes a work developed in a collaboration project between the Minho University and Instituto Monsenhor Airosa (IMA), having the Museum of Textile Industry of “Bacia do Ave” as a consulting partner. The objective is to reorganize the Institute weaving job-shop and create a museum with the XXI century Jacquard weavers loom brought from Lyon by Monsenhor Airosa. In this job-shop work, the fifty years Jacquard weavers loom still manufacture the famous industrial art. This paper emphasis is put on the job-shop reorganization that makes to order bedspread, face towel and table-cloth, napkin and raw cloth. The diversity and complexity of these products is small but exclusive that the Institute wants to spread in handcraft fairs and shops adopting repetitive production