Identification of the het-r vegetative incompatibility gene of Podospora anserina as a member of the fast evolving HNWD gene family

In fungi, vegetative incompatibility is a conspecific non-self recognition mechanism that restricts formation of viable heterokaryons when incompatible alleles of specific het loci interact. In Podospora anserina, three non-allelic incompatibility systems have been genetically defined involving interactions between het-c and het-d, het-c and het-e, het-r and het-v. het-d and het-e are paralogues belonging to the HNWD gene family that encode proteins of the STAND class. HET-D and HET-E proteins comprise an N-terminal HET effector domain, a central GTP binding site and a C-terminal WD repeat domain constituted of tandem repeats of highly conserved WD40 repeat units that define the specificity of alleles during incompatibility. The WD40 repeat units of the members of this HNWD family are undergoing concerted evolution. By combining genetic analysis and gain of function experiments, we demonstrate that an additional member of this family, HNWD2, corresponds to the het-r non-allelic incompatibility gene. As for het-d and het-e, allele specificity at the het-r locus is determined by the WD repeat domain. Natural isolates show allelic variation for het-

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Impact of second phase content over rheological behaviour of rock salt under cyclic loading conditions applied to Underground Gas Storage

The use of caverns in rock salt for Underground Gas Storage (UGS) and Compressed Air Energy Storage (CAES) have been identified as a strategic option to meet seasonal energy demand fluctuations in the electricity grid. More recently, the Department for Business, Energy and Industrial Strategy (BEIS) presented for the UK Clean Growth strategy a plan to also integrate rock salt caverns as a storage solution for co-located carbon capture, utilisation and storage (CCUS) and hydrogen production. The creation of caverns in halite formations and the operational activities of gas injection and withdrawal occurring under lithostatic pressure are known to lead to local deviatoric stresses, resulting in rock salt creep deformation. Additionally, periodic injection-production activities in response to seasonal temperature changes and associated gas consumption imply regular fluctuation of both mechanical and thermal stresses in salt caverns. Rock salt is mainly composed of halite and has low i) creep strength, ii) porosity, iii) permeability, and iv) density, making it a very good seal rock to store gas. It also typically contains secondary mineral phases (e.g. anhydrite, polyhalite, carnallite, kieserite), as well as fluids trapped in inclusions in the halite crystals, at halite grain boundaries, or in pores. This presence of other minerals besides halite, or other rock layers between the rock salt formations at a range of scales, can have significant effects on the micro and macro-mechanical properties due to their different rheological behaviours, notably weakening the rock salt under high-stress conditions. This project investigates the impact of the secondary mineral phase content on the rock salt mechanical behaviour under cyclic loading conditions. A series of cyclic mechanical loading experiments, at two different ranges of cyclic mechanical load, have been performed on different rock salt samples with different types and amounts of second phase minerals content. In the first set of tests, different confining pressures of 12, 25 and 45 MPa and different temperatures, of 22-25, 55 and 75ºC, have been applied whilst the axial stress was cycled between 4.5 and 7.5 MPa, at 0.5 kN/s loading rate, during 48h (7200 cycles). In the second set of experiments, the axial stress was cycled between 6 and 20 MPa, at 0.5 kN/s loading rate, during 48h (7200 cycles) and confining pressures of 25 and 45MPa and temperatures of 22-25, 55 and 75ºC. Thin sections of each sample's microstructures, before and after mechanical deformation, were analysed by transmitted light microscopy and Scanning Electron Microscopy (SEM) to identify the micro-mechanisms and early damage induced by the cyclic loading conditions. The results demonstrate that high second phase content such as anhydrite layering operates as a strength weakening agent by displaying larger brittle deformation features in comparison to samples with a lower content in anhydrite, polyhalite or clay as second phase content. This rheological behaviour is further exacerbated by the cycling mechanical conditions and recorded by a marked step on Young's modulus and Poisson's ratio value evolution. The microstructure analysis reveals how halite grains accommodate most of the deformation induced by the cyclic mechanical loading conditions through brittle deformation with micro-fracturing network development. Other structures from different deformation mechanisms are also discussed. Two types of new porosity are observed: i) pores around isolated crystals of second phase minerals as a result of grain rotation under cyclic mechanical deformation, and ii) micro-cracks in areas with a high concentration of secondary minerals (such as anhydrite, polyhalite, carnallite or kieserite). This porosity change has strong implications for both the mechanical behaviour of the material and its potential permeability

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Del Laboratori a la Llei

Dos professors de la UAB, el Dr. Adolf Tobeña i el Dr. Óscar Vilarroya van organitzar el novembre de 2012 unes jornades de Neuroètica titulades "From Lab to Law". Ara es publica una compilació d'articles fruit d'aquesta trobada. La Neuroètica analitza les bases neurobiològiques de temes sociològics fonamentals i inclou una exploració de conceptes ètics com el judici moral, la predisposició vers la criminalitat i la responsabilitat legal.Dos profesores de la UAB, el Dr. Adolf Tobeña y el Dr. Óscar Vilarroya, organizaron en noviembre de 2012 unas jornadas de Neuroética tituladas "From Lab to Law". Ahora se publica una compilación de artículos fruto de este encuentro. La Neuroética analiza las bases neurobiológicas de temas sociológicos fundamentales e incluye una exploración de conceptos éticos como el juicio moral, la predisposición hacia la criminalidad y la responsabilidad legal.Two professors from the UAB, Dr Adolf Tobeña and Dr Oscar Vilarroya, organised a conference on Neuroethics titled "From Lab to Law" in November 2012. Now a compilation of articles from this meeting has been published. The Neuroethics examines the neurobiological basis of fundamental sociological issues and includes an exploration of ethical concepts such as moral judgement, the predisposition to crime and legal liability

La répartition des populations piscicoles en Creuse (Limousin), l’apport géographique des pêches électriques en tête de bassin

Le département de la Creuse a une situation hydrologique de tête de bassin, que le bon état écologique des cours d’eau permet de considérer comme un espace de référence. Les pêches électriques sont utilisées de manière géographique pour cartographier la répartition des poissons représentatifs d’une certaine qualité des eaux et leur suivi pendant sept ans sur un vaste espace de 5 600km². D’année en année, les espèces peu exigeantes (chevesne et vandoise) progressent de l’aval vers l’amont, tandis que les espèces les plus exigeantes (vairon) régressent pour ne plus subsister qu’en tête de bassin. Ces espèces sont les traceurs d’une dégradation des conditions physico-chimiques ou sédimentaires remontant d’aval en amont.The department of the Creuse is located in the highlands of the French Central Massif, where the headwater catchments constitute a reference area for the ecologically healthy small watercourses. Electrofishing is used here in a geographical way in order to chart the repartition of fish species representative of a certain water quality, covering a period of seven years and a large area of 5 600 km². Over the years, populations of the least sensitive species (chub and dace) progress towards upstream waters, while the most sensitive species (minnows) regress and only subsist in the headwaters. These species are indicators of a degradation of physicochemical or sedimentary conditions moving upstream

Impact of second phase content over rheological behaviour of rock salt under cyclic loading conditions applied to Underground Gas Storage

The use of caverns in rock salt for Underground Gas Storage (UGS) and Compressed Air Energy Storage (CAES) have been identified as a strategic option to meet seasonal energy demand fluctuations in the electricity grid. More recently, the Department for Business, Energy and Industrial Strategy (BEIS) presented for the UK Clean Growth strategy a plan to also integrate rock salt caverns as a storage solution for co-located carbon capture, utilisation and storage (CCUS) and hydrogen production. The creation of caverns in halite formations and the operational activities of gas injection and withdrawal occurring under lithostatic pressure are known to lead to local deviatoric stresses, resulting in rock salt creep deformation. Additionally, periodic injection-production activities in response to seasonal temperature changes and associated gas consumption imply regular fluctuation of both mechanical and thermal stresses in salt caverns. Rock salt is mainly composed of halite and has low i) creep strength, ii) porosity, iii) permeability, and iv) density, making it a very good seal rock to store gas. It also typically contains secondary mineral phases (e.g. anhydrite, polyhalite, carnallite, kieserite), as well as fluids trapped in inclusions in the halite crystals, at halite grain boundaries, or in pores. This presence of other minerals besides halite, or other rock layers between the rock salt formations at a range of scales, can have significant effects on the micro and macro-mechanical properties due to their different rheological behaviours, notably weakening the rock salt under high-stress conditions. This project investigates the impact of the secondary mineral phase content on the rock salt mechanical behaviour under cyclic loading conditions. A series of cyclic mechanical loading experiments, at two different ranges of cyclic mechanical load, have been performed on different rock salt samples with different types and amounts of second phase minerals content. In the first set of tests, different confining pressures of 12, 25 and 45 MPa and different temperatures, of 22-25, 55 and 75ºC, have been applied whilst the axial stress was cycled between 4.5 and 7.5 MPa, at 0.5 kN/s loading rate, during 48h (7200 cycles). In the second set of experiments, the axial stress was cycled between 6 and 20 MPa, at 0.5 kN/s loading rate, during 48h (7200 cycles) and confining pressures of 25 and 45MPa and temperatures of 22-25, 55 and 75ºC. Thin sections of each sample's microstructures, before and after mechanical deformation, were analysed by transmitted light microscopy and Scanning Electron Microscopy (SEM) to identify the micro-mechanisms and early damage induced by the cyclic loading conditions. The results demonstrate that high second phase content such as anhydrite layering operates as a strength weakening agent by displaying larger brittle deformation features in comparison to samples with a lower content in anhydrite, polyhalite or clay as second phase content. This rheological behaviour is further exacerbated by the cycling mechanical conditions and recorded by a marked step on Young's modulus and Poisson's ratio value evolution. The microstructure analysis reveals how halite grains accommodate most of the deformation induced by the cyclic mechanical loading conditions through brittle deformation with micro-fracturing network development. Other structures from different deformation mechanisms are also discussed. Two types of new porosity are observed: i) pores around isolated crystals of second phase minerals as a result of grain rotation under cyclic mechanical deformation, and ii) micro-cracks in areas with a high concentration of secondary minerals (such as anhydrite, polyhalite, carnallite or kieserite). This porosity change has strong implications for both the mechanical behaviour of the material and its potential permeability