Suicidal ideation in an adolescent clinical sample: Attachment patterns and clinical implications

Investigated the relationship between attachment patterns and suicidal ideation in a clinical sample of 116 adolescents (aged 10–17 yrs). Ss were assessed on level of current ideation through self-report questionnaires. Lethality of methods contemplated was also rated on a subset of the sample (16 Ss) who, in addition to endorsing current suicidal ideation, presented a plan on a diagnostic interview. Quality of attachment to caregivers based on a semistructured clinical interview was assessed using K. Bartholomew\u27s (see record 1990-30882-001) 2-dimensional, 4-category model of attachment. Categorical analyses indicated that youth with predominantly fearful or preoccupied attachment were more likely to endorse suicidal ideation than were predominantly secure or dismissing youth. Severity of suicidal ideation was positively correlated with ratings of fearfulness and negatively correlated with ratings on the secure and dismissing patterns. Greater lethality in methods of contemplated suicide was positively correlated with preoccupied tendencies. The importance of attachment theory for understanding the factors underlying suicidal ideation in troubled youth is discussed and implications for therapeutic intervention are presented

A coalescent dual process for a Wright-Fisher diffusion with recombination and its application to haplotype partitioning

Duality plays an important role in population genetics. It can relate results from forwards-in-time models of allele frequency evolution with those of backwards-in-time genealogical models; a well known example is the duality between the Wright–Fisher diffusion for genetic drift and its genealogical counterpart, the coalescent. There have been a number of articles extending this relationship to include other evolutionary processes such as mutation and selection, but little has been explored for models also incorporating crossover recombination. Here, we derive from first principles a new genealogical process which is dual to a Wright–Fisher diffusion model of drift, mutation, and recombination. The process is reminiscent of the ancestral recombination graph , a widely-used multilocus genealogical model, but here ancestral lineages are typed and transition rates are regarded as being conditioned on an observed configuration at the leaves of the genealogy. Our approach is based on expressing a putative duality relationship between two models via their infinitesimal generators, and then seeking an appropriate test function to ensure the validity of the duality equation. This approach is quite general, and we use it to find dualities for several important variants, including both a discrete L-locus model of a gene and a continuous model in which mutation and recombination events are scattered along the gene according to continuous distributions. As an application of our results, we derive a series expansion for the transition function of the diffusion. Finally, we study in further detail the case in which mutation is absent. Then the dual process describes the dispersal of ancestral genetic material across the ancestors of a sample. The stationary distribution of this process is of particular interest; we show how duality relates this distribution to haplotype fixation probabilities. We develop an efficient method for computing such probabilities in multilocus models

Figures de l'intellectuel au Québec : analyse des pratiques discursives orientées vers la construction de soi en tant qu'intellectuel

La présente recherche a pour but d'étudier comment se construisent des figures de l'intellectuel québécois contemporain par le biais du discours écrit. Pour ce faire, cinq textes publiés entre les années 2005 et 2010 sur différentes plates-formes médiatiques québécoises seront analysés dans le but de comprendre comment les auteurs mettent en place certaines pratiques discursives dans le but de se construire un éthos de l'intellectuel. La méthodologie privilégiée mobilise de nombreux critères inspirés de la pragmatique et des théories de l'analyse du discours, ce qui permet d'étudier le texte de manière exhaustive. En supposant que le discours est l'élément structurant de la construction de figures de l'intellectuel, nous observerons le corpus sous divers angles complémentaires, à savoir la dimension de l'énoncé, de l'énonciation, de l'interaction et de la stratégie discursive. La particularité d'une telle recherche est d'offrir un regard nouveau sur cette notion fort étudiée qu'est l'intellectuel, puisqu'il est ici observé comme un objet en construction dans les textes et entendu comme le résultat d'une certaine pratique de soi. Au terme de ce parcours, chacun des textes permettra de dégager des modalités d'appropriation du statut d'intellectuel, mais aussi de proposer une réflexion sur le statut et sur les conditions d'émergence de figures de l'intellectuel.\ud ______________________________________________________________________________ \ud MOTS-CLÉS DE L’AUTEUR : intellectuel, discours, pragmatique, pratique discursive, construction de soi

A valence bond view of isocyanides' electronic structure

International audienceHigh level Valence Bond calculations support a predominantly carbenic electronic structure for isocyanides, with a secondary zwitterionic character, despite their linear geometry. This geometry results from the significant energetic stabilization due to nitrogen π lone pair donation. Results are not changed by substitution or solvation effects

Evolutionary games in the multiverse

Evolutionary game dynamics of two players with two strategies has been studied in great detail. These games have been used to model many biologically relevant scenarios, ranging from social dilemmas in mammals to microbial diversity. Some of these games may in fact take place between a number of individuals and not just between two. Here, we address one-shot games with multiple players. As long as we have only two strategies, many results from two player games can be generalized to multiple players. For games with multiple players and more than two strategies, we show that statements derived for pairwise interactions do no longer hold. For two player games with any number of strategies there can be at most one isolated internal equilibrium. For any number of players $\boldsymbol{d}$ with any number of strategies n, there can be at most (d-1)^(n-1) isolated internal equilibria. Multiplayer games show a great dynamical complexity that cannot be captured based on pairwise interactions. Our results hold for any game and can easily be applied for specific cases, e.g. public goods games or multiplayer stag hunts

Determination of stable branches of relative equilibria of the NN-vortex problem on the sphere

We consider the $N$-vortex problem on the sphere assuming that all vorticities have equal strength. We investigate relative equilibria (RE) consisting of $n$ latitudinal rings which are uniformly rotating about the vertical axis with angular velocity $\omega$. Each such ring contains $m$ vortices placed at the vertices of a concentric regular polygon and we allow the presence of additional vortices at the poles. We develop a framework to prove existence and orbital stability of branches of RE of this type parametrised by $\omega$. Such framework is implemented to rigorously determine and prove stability of segments of branches using computer-assisted proofs. This approach circumvents the analytical complexities that arise when the number of rings $n\geq 2$ and allows us to give several new rigorous results. We exemplify our method providing new contributions consisting in the determination of enclosures and proofs of stability of several equilibria and RE for $5\leq N\leq 12$.Comment: 60 page