7,953 research outputs found

    Lagrangians for invariant sub-spaces of the squared Pauli-Lubanski vector

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    We present an alternative formalism to the Rarita-Schwinger framework for the description of "has-been" higher spins at rest that avoids the Velo-Zwanziger problem.Comment: 3 pages, Contribution to the X Mexican School on Particles and Fields, 2002; The calculations by the symbolic program Mathematica have been performed by us during the time period Sept. 10, 2002-Febr. 05, 2003 at the computer heritage.reduaz,mx, courtesy D.V.Ahluwali

    Optimal Brand Umbrella Size

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    Role of heat generation and thermal diffusion during frontal photopolymerization

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    Frontal photopolymerization (FPP) is a rapid and versatile solidification process that can be used to fabricate complex three-dimensional structures by selectively exposing a photosensitive monomer-rich bath to light. A characteristic feature of FPP is the appearance of a sharp polymerization front that propagates into the bath as a planar traveling wave. In this paper, we introduce a theoretical model to determine how heat generation during photopolymerization influences the kinetics of wave propagation as well as the monomer-to-polymer conversion profile, both of which are relevant for FPP applications and experimentally measurable. When thermal diffusion is sufficiently fast relative to the rate of polymerization, the system evolves as if it were isothermal. However, when thermal diffusion is slow, a thermal wavefront develops and propagates at the same rate as the polymerization front. This leads to an accumulation of heat behind the polymerization front which can result in a significant sharpening of the conversion profile and acceleration of the growth of the solid. Our results also suggest that a novel way to tailor the dynamics of FPP is by imposing a temperature gradient along the growth directio

    From vortex molecules to the Abrikosov lattice in thin mesoscopic superconducting disks

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    Stable vortex states are studied in large superconducting thin disks (for numerical purposes we considered with radius R = 50 \xi). Configurations containing more than 700 vortices were obtained using two different approaches: the nonlinear Ginzburg-Landau (GL) theory and the London approximation. To obtain better agreement with results from the GL theory we generalized the London theory by including the spatial variation of the order parameter following Clem's ansatz. We find that configurations calculated in the London limit are also stable within the Ginzburg-Landau theory for up to ~ 230 vortices. For large values of the vorticity (typically, L > 100), the vortices are arranged in an Abrikosov lattice in the center of the disk, which is surrounded by at least two circular shells of vortices. A Voronoi construction is used to identify the defects present in the ground state vortex configurations. Such defects cluster near the edge of the disk, but for large L also grain boundaries are found which extend up to the center of the disk.Comment: 15 pages, 10 figures, RevTex4, submitted to Phys. Rev.

    A semantic web service-based architecture for the interoperability of e-government services

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    We propose a semantically-enhanced architecture to address the issues of interoperability and service integration in e-government web information systems. An architecture for a life event portal based on Semantic Web Services (SWS) is described. The architecture includes loosely-coupled modules organized in three distinct layers: User Interaction, Middleware and Web Services. The Middleware provides the semantic infrastructure for ontologies and SWS. In particular a conceptual model for integrating domain knowledge (Life Event Ontology), application knowledge (E-government Ontology) and service description (Service Ontology) is defined. The model has been applied to a use case scenario in e-government and the results of a system prototype have been reported to demonstrate some relevant features of the proposed approach

    Approaching Document Review in a Systematic Way

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    Blog post to AEA365, a blog sponsored by the American Evaluation Association (AEA) dedicated to highlighting Hot Tips, Cool Tricks, Rad Resources, and Lessons Learned for evaluators. The American Evaluation Association is an international professional association of evaluators devoted to the application and exploration of program evaluation, personnel evaluation, technology, and many other forms of evaluation. Evaluation involves assessing the strengths and weaknesses of programs, policies, personnel, products, and organizations to improve their effectiveness

    Letter from David M. Cabral to Faculty

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    Providence College Department of Theatre, Dance & Film Letter from David Cabral (Managing Director, Blackfriars Theatre), to faculty about Our Country\u27s Good\u27s acceptance into the American Theatre Festival. February 18, 1992https://digitalcommons.providence.edu/country_pubs/1000/thumbnail.jp

    HLA-DR in Cytotoxic T lymphocytes predicts breast cancer patients' response to neoadjuvant chemotherapy

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    Prediction of breast cancer response to Neoadjuvant Chemotherapy (NACT) is an urgent need to promptly direct non-responder patients to alternative therapies. Infiltrating T lymphocytes, namely cytotoxic T lymphocytes (CTLs) have been appointed as predictors of response. However, cancer cells have the ability to dampen CTLs' activity and thus, the prognostic value of the CTLs, per se, is debatable. Here, we disclose that more than the occurrence of CTLs, it is their activation state, revealed by HLA-DR expression, that can accurately predict response to NACT. Flow cytometry analysis of breast cancer biopsies showed that the frequency of CTLs and other lymphocytes were similar regardless disease stage and between NACT responders and non-responders. However, only breast cancer patients without axillary lymph node metastasis and NACT responders have HLA-DRhi CTLs. Interestingly, HLA-DR levels in tumor CTLs is correlated with HLA-DR levels in systemic CTLs. These HLA-DR+ CTLs produce IFN-γ and Granzyme B, enlightening their effector and probable anti-tumor activity profile. Moreover, the level of HLA-DR in CTLs is negatively correlated with the level of HLA-DR in T regulatory lymphocytes and with immunosuppressive and pro-tumor molecules in the tumor microenvironment. Hence, HLA-DR levels in CTLs is a highly sensitive and specific potential predictive factor of NACT-response, which can be assessed in blood to guide therapeutic decisions.Fundacao para a Ciencia e Tecnologia: PD/BD/114023/2015; PTDC/BBB-BMD/4497/2014. Liga Portuguesa Contra o Cancroinfo:eu-repo/semantics/publishedVersio

    Letter from David M. Cabral to the Dominican Community

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    Providence College Department of Theatre, Dance & Film Blackfriars Theatre Letter from David Cabral (TDF Managing Director) to the Dominican community regarding the production of Blood and Ice. September 28, 1989https://digitalcommons.providence.edu/blood_pubs/1000/thumbnail.jp
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