769 research outputs found

    Trajectory Analysis for Sport and Video Surveillance

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    In video surveillance and sports analysis applications, object trajectories offer the possibility of extracting rich information on the underlying behavior of the moving targets. To this end we introduce an extension of Point Distribution Models (PDM) to analyze the object motion in their spatial, temporal and spatiotemporal dimensions. These trajectory models represent object paths as an average trajectory and a set of deformation modes, in the spatial, temporal and spatiotemporal domains. Thus any given motion can be expressed in terms of its modes, which in turn can be ascribed to a particular behavior. The proposed analysis tool has been tested on motion data extracted from a vision system that was tracking radio-guided cars running inside a circuit. This affords an easier interpretation of results, because the shortest lap provides a reference behavior. Besides showing an actual analysis we discuss how to normalize trajectories to have a meaningful analysis

    High Temperature Emissivity, Reflectivity, and X-ray absorption of BiFeO3

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    We report on the lattice evolution of BiFeO3 as function of temperature using far infrared emissivity, reflectivity, and X-ray absorption local structure. A power law fit to the lowest frequency soft phonon in the magnetic ordered phase yields an exponent {\beta}=0.25 as for a tricritical point. At about 200 K below TN~640 K it ceases softening as consequence of BiFeO3 metastability. We identified this temperature as corresponding to a crossover transition to an order-disorder regime. Above ~700 K strong band overlapping, merging, and smearing of modes are consequence of thermal fluctuations and chemical disorder. Vibrational modes show band splits in the ferroelectric phase as emerging from triple degenerated species as from a paraelectric cubic phase above TC~1090 K. Temperature dependent X-ray absorption near edge structure (XANES) at the Fe K-edge shows that lower temperature Fe3+ turns into Fe2+. While this matches the FeO w\"ustite XANES profile, the Bi LIII-edge downshift suggests a high temperature very complex bond configuration at the distorted A perovskite site. Overall, our local structural measurements reveal high temperature defect-induced irreversible lattice changes, below, and above the ferroelectric transition, in an environment lacking of long-range coherence. We did not find an insulator to metal transition prior to melting.Comment: Accepted for publicatio

    Collective Phase-like Mode and the Role of Lattice Distortions at TN~TC in RMn2O5 (R= Pr, Sm, Gd, Tb, Bi)

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    We report on electronic collective excitations in RMn2O5 (R= Pr, Sm, Gd, Tb) showing condensation starting at and below TN\simTC\sim40-50 K. Its origin is understood as partial delocalized eg electron orbitals in the Jahn-Teller distortion of the pyramids dimmer with strong hybridized Mn3+-O bonds. Our local probes, Raman, infrared, and X-ray absorption, back the conclusion by which there is no structural phase transition at TN\simTC. Ferroelectricity is magnetically assisted by electron localization triggering lattice polarizability by unscreening. We have also found phonon hardening as the rare earth is sequentially replaced. This is understood as consequence of lanthanide contraction. It is suggested that partially f-electron screened Rare Earth nuclei might be introducing a perturbation to eg electrons prone to delocalize as the superexchange interaction takes place.Comment: Journal of Physics Cond. Matter April 12, 2012. In pres

    IRX-2, a novel biologic, favors the expansion of T effector over T regulatory cells in a human tumor microenvironment model

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    IRX-2, a natural cytokine biological with multiple components, has been used in preclinical and clinical studies to promote antitumor activity of T lymphocytes. To define cellular mechanisms responsible for antitumor effects of IRX-2, its ability to induce effector T cells (Teff) was examined in a model simulating the tumor microenvironment. An in vitro model containing conventional CD4+CD25− cells co-cultured with autologous immature dendritic cells, irradiated tumor cells, and cytokines was used to study differentiation and expansion of regulatory T cells (Treg) and Teff in the presence and absence of IRX-2. Phenotype, suppressor function, signaling, and cytokine production were serially measured using flow cytometry, Western blots, CFSE-based suppressor assays, and Luminex-based analyses. The presence of IRX-2 in the co-cultures promoted the induction and expansion of IFN-Îł+Tbet+ Teff and significantly (p < 0.01) decreased the induction of inducible IL-10+TGF-ÎČ+ Treg. The responsible mechanism involved IFN-Îł-driven T cell polarization towards Teff and suppression of Treg differentiation. In an in vitro model simulating the human tumor microenvironment, IRX-2 promoted Teff expansion and antitumor activity without inducing Treg. Thus, IRX-2 could be considered as a promising component of future antitumor therapies

    EficĂĄcia do exercĂ­cio fĂ­sico na fadiga dos pacientes com cĂąncer durante o tratamento ativo: revisĂŁo sistemĂĄtica e meta-anĂĄlise

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    El objetivo del estudio fue determinar la efectividad del ejercicio fĂ­sico en la fatiga de pacientes con cĂĄncer durante el tratamiento activo. Las bases de datos de PubMed Central, EMBASE y OVID fueron consultadas hasta abril de 2014 para identificar ensayos clĂ­nicos aleatorizados, que evaluaran el efecto del ejercicio en la fatiga de pacientes con cĂĄncer sometidos a tratamiento activo. Once estudios (n = 1.407) fueron incluidos. La quimioterapia fue el tratamiento mĂĄs comĂșn (n = 1.028). Los estudios tuvieron bajo riesgo de sesgo y alta calidad metodolĂłgica. Las estimaciones de efecto mostraron que el ejercicio fĂ­sico mejorĂł significativamente la fatiga (SMD = -3,0; IC95%: -5,21; -0,80), p < 0,0001. Se encontraron efectos similares para el entrenamiento de resistencia (SMD = -4,5; IC95%: -7,24; -1,82), p = 0,001. Se encontraron mejoras significativas en pacientes con cĂĄncer de mama y de prĂłstata (p < 0,05). El ejercicio es una intervenciĂłn segura y eficaz en el control de la fatiga en pacientes sometidos a tratamiento activoThis study aimed to determine the effectiveness of physical exercise in decreasing fatigue in cancer patients during active treatment. The PubMed Central, EMBASE, and OVID databases were consulted up to April 2014 to identify randomized clinical trials that evaluated the effect of exercise on fatigue in cancer patients undergoing active treatment. Eleven studies (n = 1,407) were included. Chemotherapy was the most common form of treatment (n = 1,028). The studies showed a low risk of bias and high methodological quality. Effect estimates showed that physical exercise significantly improved fatigue (SMD = -3.0; 95%CI: -5.21; -0.80), p < 0.0001. Similar effects were found for resistance training (SMD = -4.5; 95%CI: -7.24; -1.82), p = 0.001. Significant improvements were found in breast and prostate cancer patients (p < 0.05). Exercise is a safe and effective intervention in the management fatigue in cancer patients undergoing active treatmentO objetivo foi determinar a efetividade do exercĂ­cio fĂ­sico sobre a fadiga em pacientes com cĂąncer durante o tratamento ativo. As bases de dados PubMed Central, EMBASE e OVID foram consultadas atĂ© abril de 2014 para identificar ensaios clĂ­nicos randomizados que avaliaram o efeito do exercĂ­cio sobre a fadiga em pacientes com cĂąncer em tratamento ativo. Onze estudos (n = 1.407) foram incluĂ­dos. A quimioterapia foi o tratamento mais comum (n = 1.028). Os estudos tiveram baixo risco de viĂ©s e alta qualidade metodolĂłgica. As estimativas de efeito mostraram que o exercĂ­cio melhorou significativamente a fadiga (DMP = -3,0; IC95%: -5,21; -0,80), p < 0,0001. Efeitos semelhantes sobre o treinamento de resistĂȘncia (DMP = -4,5; IC95%: -7,24; -1,82), p = 0,001 foram encontrados. O exercĂ­cio fĂ­sico Ă© uma intervenção segura e eficaz contra a fadiga em pacientes submetidos ao tratamento ativoEl presente trabajo forma parte del Proyecto PrĂĄctica del autoexamen de seno y los conocimientos, factores de riesgo y estilos de vida relacionados con el cĂĄncer de mama en mujeres jĂłvenes de la Universidad Santo TomĂĄs de BogotĂĄ: un anĂĄlisis transversal (9ÂȘ Convocatoria FODEIN- CĂłdigo del proyecto 4110060001 - 008)
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