Symplectic torus actions with coisotropic principal orbits

In this paper we completely classify symplectic actions of a torus $T$ on a compact connected symplectic manifold $(M, \sigma)$ when some, hence every, principal orbit is a coisotropic submanifold of $(M, \sigma)$. That is, we construct an explicit model, defined in terms of certain invariants, of the manifold, the torus action and the symplectic form. The invariants are invariants of the topology of the manifold, of the torus action, or of the symplectic form. In order to deal with symplectic actions which are not Hamiltonian, we develop new techniques, extending the theory of Atiyah, Guillemin-Sternberg, Delzant, and Benoist. More specifically, we prove that there is a well-defined notion of constant vector fields on the orbit space $M/T$. Using a generalization of the Tietze-Nakajima theorem to what we call $V$-parallel spaces, we obtain that $M/T$ is isomorphic to the Cartesian product of a Delzant polytope with a torus. We then construct special lifts of the constant vector fields on $M/T$, in terms of which the model of the symplectic manifold with the torus action is defined

Moduli spaces of toric manifolds

We construct a distance on the moduli space of symplectic toric manifolds of dimension four. Then we study some basic topological properties of this space, in particular, path-connectedness, compactness, and completeness. The construction of the distance is related to the Duistermaat-Heckman measure and the Hausdorff metric. While the moduli space, its topology and metric, may be constructed in any dimension, the tools we use in the proofs are four-dimensional, and hence so is our main result.Comment: To appear in Geometriae Dedicata, minor changes to previous version, 19 pages, 6 figure

Multicultural literature: changes in perceptions and attitudes in fourth graders

In 1954, the Supreme Court voted to end segregation in American public schools. However, this landmark decision did not end racism, discrimination, and inequality. Students of color continue to be invisible across the curriculum. This study is a qualitative teacher action research. The purpose of the study was to assess school personnel perceptions and attitudes toward multicultural education in a rural northern California district, and how the implementation of multicultural literature changes perceptions and attitudes in fourth grade students. The setting for the study took place in Steelhead Elementary, located in a rural section of Northern California. Participants included K-8 educators, bilingual aides, and 60 fourth grade students. Teachers were given a survey, engaged in focus groups, and participated in interviews that measured their general cultural awareness. Students participated in a social justice, critical multicultural literacy curriculum. Major findings include lack of teacher cultural diversity awareness, lack of teacher support for multicultural practices, problematic curriculum, and student consciousness development. This research concludes that critical multicultural literature is essential for addressing racism, discrimination, and lack of cultural representation in the classroom

Persistent BCG bacilli perpetuate CD4 T effector memory and optimal protection against tuberculosis

AbstractTuberculosis (TB) remains one of the most important infectious diseases of man and animals, and the only available vaccine (BCG) requires urgent replacement or improvement. To facilitate this, the protective mechanisms induced by BCG require further understanding. As a live attenuated vaccine, persistence of BCG bacilli in the host may be a crucial mechanism.We have investigated the long term persistence of BCG following vaccination and the influence on the induced immune response and protection, using an established murine model. We sought to establish whether previously identified BCG-specific CD4 TEM cells represent genuine long-lived memory cells of a relatively high frequency, or are a consequence of continual priming by chronically persistent BCG vaccine bacilli.By clearing persistent bacilli, we have compared immune responses (spleen and lung CD4: cytokine producing T effector/TEM; TCR-specific) and BCG-induced protection, in the presence and absence of these persisting vaccine bacilli. Viable BCG bacilli persisted for at least 16 months post-vaccination, associated with specific CD4 T effector/TEM and tetramer-specific responses. Clearing these bacilli abrogated all BCG-specific CD4 T cells whilst only reducing protection by 1log10.BCG may induce two additive mechanisms of immunity: (i) dependant on the presence of viable bacilli and TEM; and (ii) independent of these factors.These data have crucial implications on the rational generation of replacement TB vaccines, and the interpretation of BCG induced immunity in animal models

Symplectic geometry on moduli spaces of J-holomorphic curves

Let (M,\omega) be a symplectic manifold, and Sigma a compact Riemann surface. We define a 2-form on the space of immersed symplectic surfaces in M, and show that the form is closed and non-degenerate, up to reparametrizations. Then we give conditions on a compatible almost complex structure J on (M,\omega) that ensure that the restriction of the form to the moduli space of simple immersed J-holomorphic Sigma-curves in a homology class A in H_2(M,\Z) is a symplectic form, and show applications and examples. In particular, we deduce sufficient conditions for the existence of J-holomorphic Sigma-curves in a given homology class for a generic J.Comment: 16 page

Enhanced equivalent model algorithm for solar mirrors

The SolarPACES Reflectance Guideline provides an essential tool to obtain comparable reflectance measurements, but because of the lack of adequate commercial instrumentation, till now the exhaustive characterization of reflectance behaviour versus incidence ¿i and (half) acceptance angle ¿ is unachieved. An expert group in Task III has been working to outline some practicable solutions. The Equivalent Model Algorithm (EMA) was found quite promising: with few input data, EMA allows to predict any reflectance feature by computation. The recent availability of reliable reflectance measurements at oblique incidence made possible the refinement of EMA by analysing a representative set of commercial solar mirrors. This paper describes the new EMA for solar mirror, named EMA4SM, and reports its validation

A System to Generate SignWriting for Video Tracks Enhancing Accessibility of Deaf People

Video content has increased much on the Internet during last years. In spite of the efforts of different organizations and governments to increase the accessibility of websites, most multimedia content on the Internet is not accessible. This paper describes a system that contributes to make multimedia content more accessible on the Web, by automatically translating subtitles in oral language to SignWriting, a way of writing Sign Language. This system extends the functionality of a general web platform that can provide accessible web content for different needs. This platform has a core component that automatically converts any web page to a web page compliant with level AA of WAI guidelines. Around this core component, different adapters complete the conversion according to the needs of specific users. One adapter is the Deaf People Accessibility Adapter, which provides accessible web content for the Deaf, based on SignWritting. Functionality of this adapter has been extended with the video subtitle translator system. A first prototype of this system has been tested through different methods including usability and accessibility tests and results show that this tool can enhance the accessibility of video content available on the Web for Deaf people