L'interaction entre Corynespora cassiicola et Hevea brasiliensis

Des inoculations in vitro de folioles d'hévéa par des gouttes de suspension de spores d'isolats de Corynespora ou leurs pulvérisations in planta montrent des différences de résistance-sensibilité (R/S) chez les clones testés. Cette R/S varie selon l'isolat, la densité des spores, l'état physiologique de l'arbre, l'intensité lumineuse, etc. PB 260 est très sensible, GT 1 est presque totalement résistant, dans nos conditions. L'excrétion d'une toxine, isolée et identifiée comme un glycopeptide de faible masse moléculaire, dans le milieu de culture de Corynespora, ou dans le fluide de germination des spores, a été confirmée. L'utilisation de ces 2 milieux conduit au même classement R/S des 9 clones étudiés que l'inoculation par des spores. La sensibilité d'un clone d'hévéa dépendrait de son aptitude à reconnaître cette toxine et/ou de sa capacité à la neutraliser. L'emploi de cette toxine en application foliaire ponctuelle conduirait à un classement précoce de la R/S des clones en milieu naturel. Des anticorps pourraient être utilisés pour rechercher une corrélation entre la virulence des isolats et leur production de toxine. (Résumé d'auteurs

Exhumation tectonics of the ultrahigh-pressure metamorphic rocks in the Qinling orogen in east China: New petrological-structural-radiometric insights from the Shandong Peninsula

International audienceIn eastern China, the Sulu area is recognized as the eastern extension of the Qinling-Dabie Belt, which is famous for its ultrahigh-pressure (UHP) metamorphism. Although numerous petrologic and geochemical works are available, structural data are still rare. This paper provides the first extensive study of bulk geometry and kinematic analysis of the Shandong Peninsula. The study area is divided into three tectonic areas by Cretaceous faults, namely, a southern UHP belt or Sulu area, a northern migmatite area, and an eastern eclogite and migmatite area or Weihai area. Conversely to the deeply entrenched idea that the later area belongs to the North China Belt, and the two others to the South China Block (SCB), we argue that all three areas are parts of the SCB. Structural, petrologic, 40Ar/39Ar, and U/Pb data comply with this new interpretation. In the North Shandong area, mafic granulites enclosed as blocks within gneissic migmatites do not significantly differ from the Sulu and Weihai eclogites which also experienced a granulite facies overprint before migmatization. The circa 210–200 Ma age of the main ductile deformation is related to an extensional event during the Triassic (or Indosinian) orogeny. This date corresponds to the temperature climax, but the time of the pressure peak, i.e., the real age of the UHP metamorphism is discussed

Ouvrages reçus par le Bulletin Hispanique

Espagne Alarcón Sierra (Rafael), Una Rana viajera: Las crónicas y los libros de viaje de Julio Camba. – España, Renacimiento, 2010, 175 p. (Colección Iluminaciones, Filología, crítica y ensayo, 59) : bibliografía – ISBN 978-84-8472-563-3. Ángeles Naval (María), Cuestión de memoria. Estudios sobre Ramón J. Sender, Luis Cernuda y Francisco Ayala. – Zaragoza, Institución Fernando el Católico (CSIC), 2010, 158 p. (Colección de letras). – ISBN 84-9911-043-1. Benito Pérez Galdós en el cine mexicano..

Correlation, Partitioning and the Probability of Casting a Decisive Vote under the Majority Rule

The main purpose of this paper is to estimate the probability of casting a decisive vote under the majority rule for a class of random electorate models encompassing the celebrated Impartial Culture (IC) and Impartial Anonymous Culture (IAC) models. The emphasis is on the impact of correlation across votes on the order of magnitude of this event. Our proof techniques use arguments from probability theory on one hand and combinatorial and algorithmic tools for counting integer points inside convex polytopes on the other hand

The Likelihood of a Condorcet Winner in the Logrolling Setting

The purpose of this note is to compute the probability of logrolling for three different probabilistic cultures. The primary finding is that the restriction of preferences to be in accord with the condition of separable preferences creates enough additional structure among voters' preference rankings to create an increase in the likelihood that a Condorcet winner will exist with both IC and IAC-based scenarios

The Likelihood of a Condorcet Winner in the Logrolling Setting

The purpose of this note is to compute the probability of logrolling for three different probabilistic cultures. The primary finding is that the restriction of preferences to be in accord with the condition of separable preferences creates enough additional structure among voters' preference rankings to create an increase in the likelihood that a Condorcet winner will exist with both IC and IAC-based scenarios

The Likelihood of a Condorcet Winner in the Logrolling Setting

The purpose of this note is to compute the probability of logrolling for three different probabilistic cultures. The primary finding is that the restriction of preferences to be in accord with the condition of separable preferences creates enough additional structure among voters' preference rankings to create an increase in the likelihood that a Condorcet winner will exist with both IC and IAC-based scenarios

Exploring the Effects on the Electoral College of National and Regional Popular Vote Interstate Compact: An Electoral Engineering Perspective

The main purpose of this paper is to explore the consequences of the formation of either a Regional Popular Vote Interstate compact or a National Popular Vote Interstate compact on the functioning of the Electoral College. The two versions of interstate Compact which are considered here differ in only one respect: in one case the interstate compact allocates its electoral votes to the regional popular winner while in the other case it allocates these votes to the national popular winner. They both differ from the ongoing National Popular Vote Interstate Compact as it is assumed that the agreement is effective as soon as the members sign it. The decisiveness and welfare analysis are conducted for a simplified symmetric theoretical version of the Electoral College where the malapportionment problems are absent. The three most popular probabilistic models are considered and the study is conducted either from the self-interest perspective of the initiators of the interstate compact or from a general interest perspective. The analysis combines analytical arguments and simulations