The Third International Symposium on Fungal Stress – ISFUS

Stress is a normal part of life for fungi, which can survive in environments considered inhospitable or hostile for other organisms. Due to the ability of fungi to respond to, survive in, and transform the environment, even under severe stresses, many researchers are exploring the mechanisms that enable fungi to adapt to stress. The International Symposium on Fungal Stress (ISFUS) brings together leading scientists from around the world who research fungal stress. This article discusses presentations given at the third ISFUS, held in São José dos Campos, São Paulo, Brazil in 2019, thereby summarizing the state-of-the-art knowledge on fungal stress, a field that includes microbiology, agriculture, environmental science, ecology, biotechnology, medicine, and astrobiology

Molecular evolution of cyclin proteins in animals and fungi

<p>Abstract</p> <p>Background</p> <p>The passage through the cell cycle is controlled by complexes of cyclins, the regulatory units, with cyclin-dependent kinases, the catalytic units. It is also known that cyclins form several families, which differ considerably in primary structure from one eukaryotic organism to another. Despite these lines of evidence, the relationship between the evolution of cyclins and their function is an open issue. Here we present the results of our study on the molecular evolution of A-, B-, D-, E-type cyclin proteins in animals and fungi.</p> <p>Results</p> <p>We constructed phylogenetic trees for these proteins, their ancestral sequences and analyzed patterns of amino acid replacements. The analysis of infrequently fixed atypical amino acid replacements in cyclins evidenced that accelerated evolution proceeded predominantly during paralog duplication or after it in animals and fungi and that it was related to aromorphic changes in animals. It was shown also that evolutionary flexibility of cyclin function may be provided by consequential reorganization of regions on protein surface remote from CDK binding sites in animal and fungal cyclins and by functional differentiation of paralogous cyclins formed in animal evolution.</p> <p>Conclusions</p> <p>The results suggested that changes in the number and/or nature of cyclin-binding proteins may underlie the evolutionary role of the alterations in the molecular structure of cyclins and their involvement in diverse molecular-genetic events.</p

Modélisation des phénomènes thermomécaniques dans une lingotière de coulée continue

La qualité de surface et interne des produits de coulée continue dépend beaucoup du comportement du brin dans la lingotière durant la solidification. Parmi les paramètres susceptibles d’influencer ce comportement, la conicité de la lingotière tient une place éminente. Nous avons développé un modèle 2D thermomécanique du brin dans la lingotière utilisant le code d’éléments finis Lagamine. Une tranche du brin est définie perpendiculairement à l’axe de coulée avec les conditions limites suivantes : symétrie suivant les axes principaux de la section (double symétrie), contact unilatéral avec frottement le long de la surface de la lingotière et température de lingotière imposée. L’approche utilise l’état plan généralisé qui permet une épaisseur variable dans le temps et fournit une équation pour l’équilibre des forces verticales. La pression ferrostatique est également prise en compte. En raison de sa conicité, la géométrie de la lingotière n’est pas constante, mais varie lorsque la tranche progresse vers le bas. Les conditions d’échange thermique sont également modifiées, en fonction des conditions de contact entre le brin et la lingotière. Après un travail de deux années, le modèle est à présent en cours de validation pour prédire le comportement du brin dans différentes configurations (forme de la section, conicité, etc.).Modelling of the thermomechanical phenomena in a mould of continuous casting. The surface and internal quality of continuous cast products depends very much on the behaviour of the strand in the mould during solidification. Among the parameters likely to influence this behaviour, the mould taper takes a prominent part. We developed a thermomechanical 2D model of the strand in the mould using the finite element code LAGAMINE. A slice of the strand is defined perpendicularly to the casting axis with the following boundary conditions: symmetry with principal axes of the section (double symmetry), frictional unilateral contact with the mould surface and imposed mould temperature. The approach uses the generalised plane strain state that allows a variable thickness of the slice in time, and provides one equation for the vertical force equilibrium. The ferrostatic pressure is also taken into account. Due to the mould taper, the geometry of the mould is not constant, but varies as the slice is moving down. The thermal exchange conditions are also modified, depending on contact condition between the strand and the mould. After a two years work, the model is now in checking to predict behaviour of the strand in different cases (shape of the strand cross section, mould taper, etc.)

Finite element modeling of thermo-mechanical behaviour of a steel strand in continuous casting

peer reviewedSurface and internal quality of continuous cast products depends very much upon the behaviour of the strand in the mould. Among the parameters likely to influence this behaviour, the mould taper takes a prominent part. In order to understand better the influence of this parameter, we have build up a thermo-mechanical finite element model. the model includes an elasto-visco-plastic law to describe the behaviour of steel from liquid to solid state, a thermo-mechanical element that takes into account thermal expansion and mechanical behaviour of the strand, a unilateral contact element, a mobile rigid boundary element to model the mould and its taper and an adapted loading element to model the ferrostatic pressure according to the liquid or solid state