Joao Pessoa, Brazil

Federal University of Paraiba
Joao Pessoa, Brazil

The Federal University of Paraíba is a public university whose main campus is located in the city of João Pessoa, Paraíba, Brazil. Together with the Federal University of Campina Grande, it is the main university of the state of Paraiba, Brazil. UFPB offers degrees in areas such as the liberal arts , health science , engineering and technology , business, education and the fine arts . There are also campuses in Areia, Bananeiras and North Coast . Wikipedia.

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Alves A.,Federal University of São Paulo | Alves A.,Federal University of Paraiba | Dias A.G.,Federal University of ABC | Sinha K.,Syracuse University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2016

The resonance S at ~750 GeV in the diphoton channel observed by ATLAS and CMS, if it holds up, is almost certainly the (S)cion of a larger dynasty in a UV completion that may very well be connected to the hierarchy problem. At this stage, however, an effective field theory framework provides a useful way to parametrize searches for this resonance in other channels. Assuming that the excess is due to a new scalar or pseudoscalar boson, we study associated production of S ("S-strahlung") at the LHC and propose searches in several clean channels like γγℓℓ, γγℓET and ℓℓℓγET to probe dimension-5 operators coupling S to Standard Model gauge bosons. We consider a range of widths for S, from 5 GeV to 45 GeV, and find that the three channels probe complementary regions of parameter space and the suppression scale Λ. The finding of most immediate relevance is that with 3 fb-1, the LHC might already reveal new excesses in the γγℓℓ channel and a 5 (3) σ discovery may already be possible after collecting 65 (25) fb-1 of data with ℓℓℓγET events if the scale of the new physics is within ~9 TeV for couplings respecting 8 TeV LHC bounds and compatible with the observed excess in diphotons for a wide resonance as suggested by the ATLAS Collaboration. Beyond the EFT parametrization, we found realizations of models with heavy vector-like quarks and leptons which can simultaneously fit the diphoton excess and be discovered in the channels proposed here. © 2016 The Authors.

Federal University of Paraiba and Massachusetts Institute of Technology | Date: 2012-06-08

Methods and systems are provided for transporting a therapeutic or cosmetic substance into nanoporous mineralized tissue structures, such as teeth. The method may include contacting the nanoporous mineralized tissue structure with an ionic solution including the therapeutic or cosmetic substance; and simultaneously applying to the nanoporous mineralized tissue structure an electrical potential effective to transport the therapeutic or cosmetic substance into the nanopores of the nanoporous mineralized tissue structure. The system may include at least one pair of electrodes which includes a first electrode configured for contacting the nanoporous mineralized tissue structure and a second electrode; and a power source and control circuitry for generating an electrical potential between the first electrode and the second electrode effective to transport a therapeutic or cosmetic substance, in an ionic solution in contact with a surface of the nanoporous mineralized tissue structure, into the nanopores of the nanoporous mineralized tissue structure.

Bakke K.,Federal University of Paraiba | Furtado C.,Federal University of Paraiba
Annals of Physics | Year: 2015

By introducing the scalar potential as modification in the mass term of the Klein-Gordon equation, the influence of a Coulomb-type potential on the Klein-Gordon oscillator is investigated. Relativistic bound states solutions are achieved to both attractive and repulsive Coulomb-type potentials and the arising of a quantum effect characterized by the dependence of angular frequency of the Klein-Gordon oscillator on the quantum numbers of the system is shown. © 2015 Elsevier Inc.

Bakke K.,Federal University of Paraiba
International Journal of Modern Physics A | Year: 2011

We consider a neutral particle with permanent electric dipole moment interacting with a field configuration induced by the noninertial effects of the FermiWalker reference frame in the presence of a disclination and discuss the influence of curvature on the Landau - He - McKellar - Wilkens quantization. © 2011 World Scientific Publishing Company.

In this study honey samples produced by Melipona (Michmelia) seminigra merrillae, collected in seven counties distributed in the central and southern region of Amazonas state in Brazil, were analysed for their botanical origin, content and profile of phenolic compounds, and antioxidant and antimicrobial activities. Twenty-two pollen types were identified. The total phenolic content ranged from 17 to 66 mg GAE/g of extract; the highest contents were found in honeys produced from pollen types such as Clidemia and Myrcia. The antioxidant activity was higher in the samples that contained higher quantities of phenolic compounds. In relation to the antibacterial activity, samples CAD3, CAD4 and SAD3 presented the best results. Fourteen phenolic compounds were determined. Among them, we identified the flavonoid taxifolin, which has not previously been described in honeys from stingless bees, and we report the identification of catechol in Brazilian honey samples for the first time. Copyright © 2013 Elsevier Ltd. All rights reserved.

Bakke K.,Federal University of Paraiba
Annals of Physics | Year: 2014

We investigate torsion and noninertial effects on a spin-1/2 quantum particle in the nonrelativistic limit of the Dirac equation. We consider the cosmic dislocation spacetime as a background and show that a rotating system of reference can be used out to distances which depend on the parameter related to the torsion of the defect. Therefore, we analyse torsion effects on the spectrum of energy of a nonrelativistic Dirac particle confined to a hard-wall potential in a Fermi-Walker reference frame. © 2014 Elsevier Inc.

We discuss the arising of bound states solutions of the Schrödinger equation due to the presence of a Coulomb-type potential induced by the interaction between a moving electric quadrupole moment and a magnetic field. Furthermore, we study the influence of the Coulomb-type potential on the harmonic oscillator by showing a quantum effect characterized by the dependence of the angular frequency on the quantum numbers of the system, whose meaning is that not all values of the angular frequency are allowed. © 2013 Elsevier Inc.

Pedrosa I.A.,Federal University of Paraiba
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We present a quantum description of electromagnetic waves propagating through time-dependent homogeneous nondispersive conducting and nonconducting linear media without charge sources. Based on the Coulomb gauge and the quantum invariant method, we find the exact wave functions for this problem. In addition, we construct coherent and squeezed states for the quantized electromagnetic waves and evaluate the quantum fluctuations in coordinate and momentum space as well as the uncertainty product for each mode of the electromagnetic field. © 2011 American Physical Society.

Bakke K.,Federal University of Paraiba
General Relativity and Gravitation | Year: 2013

In this contribution, we study the Dirac oscillator under the influence of noninertial effects of a rotating frame in the cosmic string spacetime. We show that both noninertial effects and the topology of the cosmic string spacetime restrict the physical region of the spacetime where the quantum particle can be placed, and discuss two different cases of bound states solutions of the Dirac equation by analysing the behaviour of the Dirac oscillator frequency. © 2013 Springer Science+Business Media New York.

Bakke K.,Federal University of Paraiba
Annalen der Physik | Year: 2012

In this work, quantum effects are discussed which arise from the interaction between an electric quadrupole moment and electric fields. It is shown that, by choosing a diagonal electric quadrupole tensor whose components are constants, the interaction between an electric quadrupole moment and electric fields gives rise to the scalar Aharonov-Bohm effect and to bound states analogous to the confinement of a quantum particle to a quantum dot. Moreover, the influence of a constant force field on the confinement analogous to a quantum dot, and the influence of an antidot-like potential on the Landau levels of an electric quadrupole moment are discussed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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