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Influence of the genetic structure of the red and blue shrimp, Aristeus antennatus (Risso, 1816), on the sustainability of a deep-sea population along a depth gradient in the western Mediterranean

  • Sardà, Francisco
  • Roldán Borassi, María Inés
  • Heras Mena, Sandra
  • Maltagliati, Ferruccio
The red and blue shrimp, Aristeus antennatus, inhabits deep shelf waters in the Mediterranean Sea, where the shallower portion of its distribution supports a large commercial fishery. Recent prospecting surveys in the western Mediterranean have detected virgin stocks dwelling at more than 1000 m, but the extent of gene flow between the exploited shallow-dwelling stock and the deep-dwelling stock is unknown. To investigate the genetic structure of the population and estimate the depth component of gene flow, a portion of the mitochondrial DNA 16S gene (547 pb) was sequenced for 321 individuals from four different depths (350, 700, 1100 and 1500 m) at a location in the Catalan Sea. Haplotype and nucleotide diversity values were low and did not significantly differ across depths. Analysis of molecular variance showed no significant genetic differences between depths. Mismatch distribution and neutrality tests indicated that A. antennatus has undergone recent demographic expansion in the two shallowest layers. Our results suggest that the species is genetically structured as a sort of metapopulation in which gene flow that occurs during the larval and juvenile stages, when larvae are carried downstream and juveniles are carried upstream by cascading, plays an important role in the resilience of the exploited layers, La gamba rosada Aristeus antennatus habita las aguas profundas del Mar Mediterráneo, donde los stocks de aguas más someras soportan una importante presión pesquera. Recientes campañas de prospección llevadas a cabo en el Mediterráneo Occidental han detectado stocks vírgenes a más de 1000 m de profundidad, pero se desconoce el flujo génico entre estos stocks y los menos profundos. Con el fin de investigar la estructura genética de dichos stocks, y estimar el componente de flujo génico entre ellos, se secuenció una porción de ADN mitocondrial, el gen 16S (547 bp) en 321 individuos procedentes de cuatro profundidades (350, 700, 1100 y 1500 m) de una localidad del mar Catalán. Los valores de diversidad haplotípica y nucleotídica fueron bajos y no resultaron significativos entre profundidades. El análisis de la varianza molecular tampoco mostró diferencias significativas entre profundidades. La distribución mismatch y los tests de neutralidad indicaron que A. antennatus tuvo una expansión demográfica reciente en las dos fracciones menos profundas. Nuestros resultados sugieren que la gamba rosada está genéticamente estructurada como una metapoblación donde el flujo génico ocurre, en parte, mediante la deriva de larvas y de juveniles, cuando éstos últimos aparecen en las zonas menos profundas en los períodos siguientes al cascading. Este aspecto juega un rol importante en la capacidad de recuperación de los stocks explotados
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[Resssenya del llibre] La catalogazione dei manoscriti miniati come strumento di conoscenza. Esperienze, metodologia, prospettive, a cura di Silvia Maddalo e Michela Torquati

  • Molina i Figueras, Joan
Ressenya del llibre 'La catalogazione dei manoscriti miniati come strumento di conoscenza. Esperienze, metodologia, prospettive', a cura di Silvia Maddalo e Michela Torquati, publicat per Istituto Storico per il Medio Evo l'any 2010. Comentari a les actes d'un congrés que es va celebrar l'abril del 2009 a Viterbo sobre la catalogació de manuscrits
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L'Assentament ibèric de Sant Sebastià de la Guarda (Palafrugell, Baix Empordà)

  • Burch, Josep
  • Rojas, Antoni
  • Vivo i Llorca, Jordi
Sobre l'assentament ibèric de Sant Sebastià de la Guarda (Palafrugell, Baix Empordà)
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Communications on quantum similarity (2): A geometric discussion on holographic electron density theorem and confined quantum similarity measures

  • Carbó-Dorca, Ramon
  • Besalú i Llorà, Emili
The so-called holographic electron density theorem (HEDT) is analyzed from an algebraic perspective, and a brief analytical point of view is also given. The connection of the HEDT with quantum similarity measures (QSM) over electronic density functions (DF) is studied using GTO functions, atomic ASA DF, and promolecular ASA DF. Restricted integration of QSM over a box of finite side length is discussed for all this DF. This work emphasizes the geometric aspects of HEDT, but for the sake of completeness, some analytical insight based on a general Taylor series expansion is also given at the end, Contract/grant sponsor: Spanish Ministerio de Educación y Ciencia; contract/grant number: CTQ2009-09370/BQU
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Exposició virtual Martin Gardner: la màgia de la ciència

  • Universitat de Girona. Biblioteca
Exposició virtual sobre el matemàtic, divulgador científic i filòsof de la ciència, Martin Gardner, que va morir a Oklahoma (EEUU) el 22 de maig del 2010
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La recerca en l’ensenyament de la geografia per al desenvolupament sostenible

  • Granados Sánchez, Jesús
Geography seems to assume an inexorable function as a bridging discipline between nature and society. Geography’s distinctive preoccupation with place, space and synthesis adds a new dimension to the analysis and pursuit of sustainable development. This paper examines the main research on geographical education for sustainable development of the last years. This research highlights mainly how education for sustainable development (ESD) is implemented into the teacher training programs and how the curriculum reorientation is interpreted in different cultural contexts, La géographie est une discipline de synthèse qui, à travers l’étude de l’espace et des lieux, peut être utile pour les questions sur le développement durable puisqu’elle intègre des connaissances des sciences naturelles, des sciences sociales et des humanités. L’enseignement de la géographie pour le développement durable est un champ de recherche relativement récent qui compte aujourd’hui avec beaucoup d’études qui nous montrent comment les différents contextes culturels interprètent l’Éducation pour le développement durable (EDS). Le but de cet article est de présenter un panorama des principaux apports qui ont été faits dans les dernières années dans ce champ de la didactique, avec une attention spéciale sur la position de la géographie dans les curriculums nationaux de l’Éducation obligatoire, la durabilité du curriculum et de la pensée, la formation initiale et continue des enseignants, La geografía es una disciplina de síntesis que, mediante el estudio del espacio i los lugares, puede ayudar en las cuestiones del desarrollo sostenible, ya que integra conocimientos de las ciencias naturales, las ciencias sociales y las humanidades. La enseñanza de la geografía para el desarrollo sostenible es un campo de investigación relativamente joven, pero cuenta ya hoy con muchas investigaciones que nos muestran como los distintos contextos culturales interpretan a la educación para el desarrollo sostenible (EDS). Este artículo tiene como finalidad presentar una panorámica de las principales aportaciones que se han hecho en los últimos años en este campo de la didàctica, con especial atención a la posición de la geografía en los currículos escolares, la sostenibilización curricular y el pensamiento, la formación inicial y continua del profesorado, La geografia és una disciplina de síntesi que, mitjançant l’estudi de l’espai i els llocs, pot ajudar en les qüestions del desenvolupament sostenible, ja que integra coneixements de les ciències naturals, les ciències socials i les humanitats. L’ensenyament de la geografia per al desenvolupament sostenible és un camp d’investigació relativament recent que disposa avui de moltes investigacions que ens mostren com els diferents contextos culturals interpreten l’educació per al desenvolupament sostenible (EDS). Aquest article té com a finalitat presentar una panoràmica de les aportacions principals que s’han fet en els darrers anys en aquest camp de la didàctica, amb una atenció especial en la posició de la geografia en els currículums nacionals de l’educació obligatòria, la sostenibilització curricular i el pensament, la formació inicial i contínua del professorat
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A global picture of the S1/S0 conical intersection seam of benzene

  • Li, Quansong
  • Mendive-Tapia, David
  • Paterson, Martin J.
  • Migani, Annapaola
  • Bearpark, Michael J.
  • Robb, Michael A.
  • Blancafort San José, Lluís
A global picture of the S1/S0intersection seam of benzene is presented. Eleven new conical intersection critical points were located at the CASSCF level, the connectivity was mapped and the energies refined with CASPT 2. There are two seam branches related with pairs of degenerate A1g/B2uand Egstates at D6hsymmetry, respectively, and the two branches are connected by a seam segment of Cssymmetry. The global energy minimum of the seam is the half-boat shaped intersection that leads to a pre-fulvenic intermediate [I.J. Palmer, I.N. Ragazos, F. Bernardi, M. Olivucci, M.A. Robb, J. Am. Chem. Soc. 115 (1993) 673]. Several other intersections that can lead to the same intermediate or vibrationally hot benzene lie in a range of 3.7 eV above the global seam minimum. There is a recurrent connectivity pattern where permutationally isomeric seam segments are connected by intersections of a higher symmetry point group, This work has been supported by Grant CTQ2008-06696 from the Spanish Ministerio de Ciencia e Innovación (MICINN)
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A linear matrix inequality approach to robust fault detection filter design of linear systems with mixed time-varying delays and nonlinear perturbations

  • Karimi, Hamid Reza
  • Zapateiro de la Hoz, Mauricio Fabián
  • Luo, Ningsu
In this paper, the problem of robust fault detection filter (RFDF) design for a class of linear systems with some nonlinear perturbations and mixed neutral and discrete time-varying delays is investigated. By using a descriptor technique, Lyapunov-Krasovskii functional and a suitable change of variables, new required sufficient conditions are established in terms of delay-dependent linear matrix inequalities (LMIs) to synthesize the residual generation scheme. Based on the Luenberger type observers, the explicit expression of the filters is derived for the fault such that both asymptotic stability and a prescribed level of disturbance attenuation are satisfied for all admissible nonlinear perturbations. A numerical example is provided to demonstrate the effectiveness and the applicability of the proposed method
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Effect of environmental factors and bulb mass on the invasive geophyte Oxalis pes-caprae development

  • Verdaguer i Murlà, Dolors
  • Sala, Anna M.
  • Vilà Suñé, Montserrat
Oxalis pes-caprae is an invasive pseudoannual plant that reproduces exclusively via offspring bulbs in the introduced range. It is most abundant in disturbed, fertile sites such as agricultural fields, but it is also found in undisturbed shrublands and shadier forest habitats. Oxalis infestation depends on long distance bulb dispersal (mainly anthropogenic) and on the ability of bulbs to grow and reproduce successfully. We conducted a greenhouse experiment to test the effects of parent bulb size on Oxalis growth and offspring production as a function of light availability (ambient and shade), planting depth (surface vs. 9 cm deep), and soil volume (full pots and pots with reduced soil volume). Oxalis grew and reproduced prolifically in all treatments. However, plant development and final offspring bulb production were sensitive to environmental conditions. Shading and reduced soil volume reduced maximum plant biomass relative to control and planting depth treatments, which produced either higher number of offspring bulbs (control) or larger offspring bulbs and higher total offspring bulb biomass (planting depth). Parent bulb size and vegetative reproductive organs had little effect on plant growth and offspring production. Our results are consistent with the lower abundance of Oxalis in undisturbed soils and shadier habitats in the field but indicate that even in these marginal habitats Oxalis can reproduce prolifically and contribute to further spread
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