4,213 research outputs found

    Nonequivalent Seiberg-Witten maps for noncommutative massive U(N) gauge theory

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    Massive vector fields can be described in a gauge invariant way with the introduction of compensating fields. In the unitary gauge one recovers the original formulation. Although this gauging mechanism can be extended to noncommutative spaces in a straightforward way, non trivial aspects show up when we consider the Seiberg-Witten map. As we show here, only a particular class of its solutions leads to an action that admits the unitary gauge fixing.Comment: General solutions for the map and important reference included, 6 pages, no figure

    Hamiltonian embedding of the massive noncommutative U(1) theory

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    We show that the massive noncommutative U(1) can be embedded in a gauge theory by using the BFFT Hamiltonian formalism. By virtue of the peculiar non-Abelian algebraic structure of the noncommutative massive U(1) theory, several specific identities involving Moyal commutators had to be used in order to make the embedding possible. This leads to an infinite number of steps in the iterative process of obtaining first-class constraints. We also shown that the involutive Hamiltonian can be constructed.Comment: 8 pages, Revtex (multicol

    Noncommutative Particles in Curved Spaces

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    We present a formulation in a curved background of noncommutative mechanics, where the object of noncommutativity θμν\theta^{\mu\nu} is considered as an independent quantity having a canonical conjugate momentum. We introduced a noncommutative first-order action in D=10 curved spacetime and the covariant equations of motions were computed. This model, invariant under diffeomorphism, generalizes recent relativistic results.Comment: 1+15 pages. Latex. New comments and results adde

    New insight into breast cancer cells involving drug combinations for dopamine and serotonin receptors

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    The breast cancer therapies available are insufficient, especially since first-line treatments, such as paclitaxel, result in drug resistance and their toxicity often limits their concentration. Strategies like drug repurposing are beneficial, and novel treatments can emerge by repurposing drugs that interfere with the dopamine and serotonin receptors, and thus influence tumor growth. In this study, the MTT assay was used to test the efficacy of such repurposed drugs commonly used for neurodegenerative disorders that act on the dopamine and serotonin receptors to reduce the MCF7 cell’s viability, either by their single use or in combination with the reference drug paclitaxel. Furthermore, the expression of vimentin and E-cadherin was assayed by immunofluorescence. The dopamine receptor-altering drugs benztropine and thioridazine resulted in the strongest reduction of cell viability when combined with paclitaxel, which may be connected to the alteration of E-cadherin rather than vimentin expression. More studies are needed to understand the mechanism of action of the combinations tested and the efficacious role of dopamine and serotonin.This work was supported by Fundação para a Ciência e Tecnologia (FCT, Portugal) and FEDER (Fundo Europeu de Desenvolvimento Regional) funds through the COMPETE 2020 Operational Programme for Competitiveness and Internationalisation (POCI), Portugal, in the framework of the project IF/00092/2014/CP1255/CT0004. N.V. thanks Fundação para a Ciência e a Tecnologia (FCT, Portugal) for supporting these studies through nationally-funded projects within the CINTESIS R&D unit (reference UIDB/4255/2020). The contents of this report are solely the responsibility of the authors and do not necessarily represent the official view of the FCT

    Using the post‐operative quality recovery scale to evaluate recovery with different neuromuscular blocking reversal agentsin the Portuguese population ‐ interim analysis results: 1AP3‐8

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    Background and Goal of Study: Post-operative Quality Recovery Scale (PQRS), is the first scale evaluating several domains of postoperative recovery. The objectives of this study were to compare overal and physiologic, cognitive, and functional domains of post-operative recovery af ter elective surgical procedures using neostigmine or sugammadex as neuromuscular blocking (NMB) reversal agents, to validate the use of PQRS in the Portuguese population and to objectively assess muscular strength recovery. Materials and Methods: Prospective multicenter observational study comparing postoperative recovery between 2 cohorts of 50 adult patients submitted to elective surgical procedures with general anesthesia using Nondepolarizing Muscle Relaxants and NMB reversal with neostigmine or sugammadex. Measurements obtained using Portuguese version of PQRS at dif ferent timepoint: baseline,15 minutes (T15), 40 minutes (T40), one and three days af ter surgery. Full recovery defined as return to values identical or higher than those measured at baseline, prior to surgery. Muscular strength measured with KERN- MAP® Dynamometer. Ethics Committees approval was obtained. Statistics used linear T-Test, Qui Square and Fisher exact test, data presented as mean±SD for continuous variables. Interim analysis results presented Results and Discussion: Thirty patients received neostigmine and 21 sugammadex. Age and BMI 50.4±11.8 and 28.6±5.6 in the neostigmine group and 38.2±12.7 and 24.7± 4.5 in the sugammadex group (p< 0,001). Overall response rate at T15 was 86% for neostigmine and 95% for sugammadex (p= 0.22). Dif ferences in favor of sugammadex group noted in nociceptive and emotional domains, 80 vs 100% respectively (p=0.04). Overall response rate at T40 was 80% for neostigmine and 65% for sugammadex (p=0.33), primarily reflecting constraints on activities of daily life. Muscular strength did not dif fer. Improvements in recovery scores from T15 to T40 were observed in both groups, without significant dif ferences . Postoperative assessments were feasible using PQRS at T15 and T40 and seem appropriate for comparisons between postoperative recovery domains and overall recovery . These preliminary results suggest nociceptive and emotional domains recovery at T15 may be faster with sugammadex. Conclusion: The results support the adopted PQRS validation process and the potential of this scale as a tool for the evaluation of post operative recovery evaluation in the Portuguese populatio

    Textile effluente treatment though oxidation via activated humidity

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    Diversos problemas envolvem as estações de tratamento de efluentes têxteis, principalmente o baixo nível de eficiência quanto a remoção da cor. Em função de normas mais rigorosas que estão sendo estabelecidas, as indústrias têxteis têm que encontrar métodos efetivos para a descoloração de seus efluentes. O presente trabalho investigou através de estudos em laboratório, a remoção de cor destes efluentes através da oxidação por via úmida ativada (Processo de Oxidação Avançada-AOP) utilizando como oxidante o peróxido de hidrogênio, ativado pela radiação ultravioleta. A fotodegradação foi realizada em batelada em um reator equipado com uma lâmpada de vapor de mercúrio de média pressão, de imersão. Três diferentes doses de peróxido de hidrogênio foram testadas (15, 30 e 45 mg/L) em amostras com diferentes pHs (3, 7 e 11). A degradação da cor mostrou seguir uma cinética de pseudo primeira ordem, sendo as condições mais adequadas para o pH alcalino, na presença de 45 mg/L de H2O2.Several problems are found in the textile effluent treatment stations, mainly the low level of efficiency concerning color removal. As a result of more rigorous standards that have been established the textile industries are forced to find effective methods for discoloration of their effluents. This work concerns a laboratory investigation on the removal of color from these effluents through oxidation by activated wet process, (Advanced Oxidation Process-OAP), using hydrogen peroxide as an oxidizing agent, activated by ultraviolet radiation. Photo-degradation was carried out in a bark in a reactor equipped with an immersion mercury vapor lamp at medium pressure. Three different dosages of hydrogen peroxide were tested (15, 30 and 45 mg/L) using samples with different pHs (3, 7, 11). Color degradation proved to follow a kinetics of pseudo first order, being the most appropriate conditions for an alkaline pH, in the presence of 45 mg/L of H2O2

    Traça voraz.

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    O ataque de Cryptoblabes gnidiella aos cachos da videira pode comprometer até 60% da produção. Além dos danos diretos, os ferimentos provocados pelo inseto abrem caminho para a proliferação de fungos. Saiba como controlar a praga

    25 and 50G optical access network deployment forecasts using bi-logistic curves

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    Different forecast scenarios for the 25G-PON and 50G-PON Globally for both ONT/ONU markets are presented based on modeling by a Bi-Logistic function with reference to GPON existing data.info:eu-repo/semantics/acceptedVersio
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