University of Toronto

About: University of Toronto is a education organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 126067 authors who have published 294940 publications receiving 13536856 citations. The organization is also known as: UToronto & U of T.

Generalized complex geometry

Abstract: Generalized complex geometry, as developed by Hitchin, contains complex and symplectic geometry as its extremal special cases. In this thesis, we explore novel phenomena exhibited by this geometry, such as the natural action of a B-field. We provide new examples, including some on manifolds admitting no known complex or symplectic structure. We prove a generalized Darboux theorem which yields a local normal form for the geometry. We show that there is an elliptic deformation theory and establish the existence of a Kuranishi moduli space. We then define the concept of a generalized Kahler manifold. We prove that generalized Kahler geometry is equivalent to a bi-Hermitian geometry with torsion first discovered by physicists. We then use this result to solve an outstanding problem in 4-dimensional bi-Hermitian geometry: we prove that there exists a Riemannian metric on the complex projective plane which admits exactly two distinct Hermitian complex structures with equal orientation. Finally, we introduce the concept of generalized complex submanifold, and show that such sub-objects correspond to D-branes in the topological A- and B-models of string theory.

Incidence, risk factors and prevention of mild traumatic brain injury: results of the WHO Collaborating Centre Task Force on Mild Traumatic Brain Injury.

Abstract: Objective: We undertook a best-evidence synthesis on the incidence, risk factors and prevention of mild traumatic brain injury. Methods: Medline, Cinahl, PsycINFO and Embase were searched for relev ...

Between facets and domains: 10 aspects of the Big Five.

Abstract: Factor analyses of 75 facet scales from 2 major Big Five inventories, in the Eugene-Springfield community sample (N=481), produced a 2-factor solution for the 15 facets in each domain. These findings indicate the existence of 2 distinct (but correlated) aspects within each of the Big Five, representing an intermediate level of personality structure between facets and domains. The authors characterized these factors in detail at the item level by correlating factor scores with the International Personality Item Pool (L. R. Goldberg, 1999). These correlations allowed the construction of a 100-item measure of the 10 factors (the Big Five Aspect Scales [BFAS]), which was validated in a 2nd sample (N=480). Finally, the authors examined the correlations of the 10 factors with scores derived from 10 genetic factors that a previous study identified underlying the shared variance among the Revised NEO Personality Inventory facets (K. L. Jang et al., 2002). The correspondence was strong enough to suggest that the 10 aspects of the Big Five may have distinct biological substrates.

Sterile-neutrinos as dark matter

Abstract: The simplest model that can accommodate a viable nonbaryonic dark matter candidate is the standard electroweak theory with the addition of right-handed (sterile) neutrinos. We consider a single generation of neutrinos with a Dirac mass [mu] and a Majorana mass [ital M] for the right-handed component. If [ital M][much gt][mu] (standard hot dark matter corresponds to [ital M]=0), then sterile neutrinos are produced via oscillations in the early Universe with energy density independent of [ital M]. However, [ital M] is crucial in determining the large scale structure of the Universe; for [ital M][similar to]100 eV, sterile neutrinos make an excellent warm dark matter candidate.

Bargaining and Markets

Abstract: Introduction. Bargaining Theory: The Axiomatic Approach. Nash's Solution. The Strategic Approach. A Model of Alternating Offers. The Relation between the Axiomatic and Strategic Approaches. A Strategic Model of Bargaining between Incompletely Informed Players. Models of Decentralized Trade: First Approach Using the Nash Solution. Strategic Bargaining in a Steady State Market. Strategic Bargaining in a Market with One-Time Entry. The Role of the Trading Procedure. The Role of Anonymity. References. Index.