106 results on '"De Albuquerque J"'
Search Results
2. Asymptotic behavior of Musielak-Orlicz-Sobolev modulars
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de Albuquerque, J. C., de Assis, L. R. S., Carvalho, M. L. M., and Salort, A.
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Mathematics - Analysis of PDEs - Abstract
In this article we study the asymptotic behavior of anisotropic nonlocal nonstandard growth seminorms and modulars as the fractional parameter goes to 1. This gives a so-called Bourgain-Brezis-Mironescu type formula for a very general family of functionals. In the particu\-lar case of fractional Sobolev spaces with variable exponent, we point out that our proof asks for a weaker regularity of the exponent than the considered in previous articles.
- Published
- 2023
3. On Fractional Musielak-Sobolev spaces and applications to nonlocal problems
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de Albuquerque, J. C., de Assis, L. R. S., Carvalho, M. L. M., and Salort, A.
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Mathematics - Analysis of PDEs ,46E30, 35R11, 47G20 - Abstract
In this work, we establish some abstract results on the perspective of the fractional Musielak-Sobolev spaces, such as: uniform convexity, Radon-Riesz property with respect to the modular function, $(S_{+})$-property, Brezis-Lieb type Lemma to the modular function and monotonicity results. Moreover, we apply the theory developed to study the existence of solutions to the following class of nonlocal problems \begin{equation*} \left\{ \begin{array}{ll} (-\Delta)_{\Phi_{x,y}}^s u = f(x,u),& \mbox{in }\Omega, u=0,& \mbox{on }\mathbb{R}^N\setminus \Omega, \end{array} \right. \end{equation*} where $N\geq 2$, $\Omega\subset \mathbb{R}^N$ is a bounded domain with Lipschitz boundary $\partial \Omega$ and $f:\Omega \times \mathbb{R} \rightarrow \mathbb{R}$ is a Carath\'{e}odory function not necessarily satisfying the Ambrosetti-Rabinowitz condition. Such class of problems enables the presence of many particular operators, for instance, the fractional operator with variable exponent, double-phase and double-phase with variable exponent operators, anisotropic fractional $p$-Laplacian, among others.
- Published
- 2023
4. Regularity results for quasilinear elliptic problems driven by the fractional $\Phi$-Laplacian operator
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Carvalho, M. L., Silva, E. D., de Albuquerque, J. C., and Bahrouni, S.
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Mathematics - Analysis of PDEs - Abstract
It is established $L^{p}$ estimates for the fractional $\Phi$-Laplacian operator defined in bounded domains where the nonlinearity is subcritical or critical in a suitable sense. Furthermore, using some fine estimates together with the Moser's iteration, we prove that any weak solution for fractional $\Phi$-Laplacian operator defined in bounded domains belongs to $L^\infty(\Omega)$ under appropriate hypotheses on the $N$-function $\Phi$. Using the Orlicz space and taking into account the fractional setting for our problem the main results are stated for a huge class of nonlinear operators and nonlinearities.
- Published
- 2021
5. Schrödinger-poisson system with zero mass in R2 involving (2, q)-Laplacian: existence, asymptotic behavior and regularity of solutions
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de Albuquerque, J. C., Carvalho, J., and Silva, E. D.
- Published
- 2023
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6. Revised regularity results for quasilinear elliptic problems driven by the $\Phi$-Laplacian operator
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Silva, E. D., Carvalho, M. L., and de Albuquerque, J. C.
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Mathematics - Analysis of PDEs - Abstract
It is establish regularity results for weak solutions of quasilinear elliptic problems driven by the well known $\Phi$-Laplacian operator given by \begin{equation*} \left\{\ \begin{array}{cl} \displaystyle-\Delta_\Phi u= g(x,u), & \mbox{in}~\Omega, u=0, & \mbox{on}~\partial \Omega, \end{array} \right. \end{equation*} where $\Delta_{\Phi}u :=\mbox{div}(\phi(|\nabla u|)\nabla u)$ and $\Omega\subset\mathbb{R}^{N}, N \geq 2,$ is a bounded domain with smooth boundary $\partial\Omega$. Our work concerns on nonlinearities $g$ which can be homogeneous or non-homogeneous. For the homogeneous case we consider an existence result together with a regularity result proving that any weak solution remains bounded. Furthermore, for the non-homogeneous case, the nonlinear term $g$ can be subcritical or critical proving also that any weak solution is bounded. The proofs are based on Moser's iteration in Orclicz and Orlicz-Sobolev spaces., Comment: Here we consider some regularity results for quasilinear elliptic problems involving nonhomoegeneous operators
- Published
- 2018
7. Revised regularity results for quasilinear elliptic problems driven by the Φ-Laplacian operator
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Silva, E. D., Carvalho, M. L., and de Albuquerque, J. C.
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- 2020
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8. Schrödinger-poisson system with zero mass in $$\mathbb {R}^2$$ involving (2, q)-Laplacian: existence, asymptotic behavior and regularity of solutions
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de Albuquerque, J. C., primary, Carvalho, J., additional, and Silva, E. D., additional
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- 2023
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9. Determination of thermal and optical parameters of melanins by photopyroelectric spectroscopy
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de Albuquerque, J. E., Giacomantonio, C., White, A., and Meredith, P.
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Condensed Matter - Soft Condensed Matter ,Condensed Matter - Disordered Systems and Neural Networks - Abstract
Photopyroelectric spectroscopy (PPE) was used to study the thermal and optical properties of electropolymerized melanins. The photopyroelectric intensity signal and its phase were independently measured as a function of wavelength, as well as a function of chopping frequency for a given wavelength in the saturation part of the PPE spectrum. Equations for both the intensity and the phase of the PPE signal were used to fit the experimental results. From the fittings we obtained for the first time, with great accuracy, the thermal diffusivity coefficient, the thermal conductivity and the specific heat of the samples, as well as a value for the condensed phase optical gap, which we found to be 1.70 eV., Comment: 4 Page Letter
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- 2005
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10. Fourth-order nonlocal type elliptic problems with indefinite nonlinearities
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Silva, Edcarlos D., de Albuquerque, J. C., and Cavalcante, T. R.
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- 2021
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11. On Fractional Musielak–Sobolev Spaces and Applications to Nonlocal Problems
- Author
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de Albuquerque, J. C., primary, de Assis, L. R. S., additional, Carvalho, M. L. M., additional, and Salort, A., additional
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- 2023
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12. Periodic and asymptotically periodic quasilinear elliptic systems
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Silva, Edcarlos D., primary, de Albuquerque, J. C., additional, and Silva, Maxwell L., additional
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- 2020
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13. POSITIVE GROUND STATES FOR A CLASS OF SUPERLINEAR -LAPLACIAN COUPLED SYSTEMS INVOLVING SCHRÖDINGER EQUATIONS
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DE ALBUQUERQUE, J. C., primary, MARCOS DO Ó, JOÃO, additional, and SILVA, EDCARLOS D., additional
- Published
- 2019
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14. Revised regularity results for quasilinear elliptic problems driven by the $$\Phi $$Φ-Laplacian operator
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Silva, E. D., primary, Carvalho, M. L., additional, and de Albuquerque, J. C., additional
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- 2019
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15. On nonquadratic fractional coupled elliptic systems in ℝ
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Silva, E. D., primary, de Albuquerque, J. C., additional, and do Ó, J. M., additional
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- 2018
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16. POSITIVE GROUND STATES FOR A CLASS OF SUPERLINEAR $(p,q)$ -LAPLACIAN COUPLED SYSTEMS INVOLVING SCHRÖDINGER EQUATIONS.
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DE ALBUQUERQUE, J. C., MARCOS DO Ó, JOÃO, and SILVA, EDCARLOS D.
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SCHRODINGER equation , *LAPLACIAN operator , *MANIFOLDS (Mathematics) - Abstract
We study the existence of positive ground state solutions for the following class of $(p,q)$ -Laplacian coupled systems $$\begin{eqnarray}\left\{\begin{array}{@{}lr@{}}-\unicode[STIX]{x1D6E5}_{p}u+a(x)|u|^{p-2}u=f(u)+\unicode[STIX]{x1D6FC}\unicode[STIX]{x1D706}(x)|u|^{\unicode[STIX]{x1D6FC}-2}u|v|^{\unicode[STIX]{x1D6FD}}, & x\in \mathbb{R}^{N},\\ -\unicode[STIX]{x1D6E5}_{q}v+b(x)|v|^{q-2}v=g(v)+\unicode[STIX]{x1D6FD}\unicode[STIX]{x1D706}(x)|v|^{\unicode[STIX]{x1D6FD}-2}v|u|^{\unicode[STIX]{x1D6FC}}, & x\in \mathbb{R}^{N},\end{array}\right.\end{eqnarray}$$ where $1. Here the coefficient $\unicode[STIX]{x1D706}(x)$ of the coupling term is related to the potentials by the condition $|\unicode[STIX]{x1D706}(x)|\leq \unicode[STIX]{x1D6FF}a(x)^{\unicode[STIX]{x1D6FC}/p}b(x)^{\unicode[STIX]{x1D6FD}/q}$ , where $\unicode[STIX]{x1D6FF}\in (0,1)$ and $\unicode[STIX]{x1D6FC}/p+\unicode[STIX]{x1D6FD}/q=1$. Using a variational approach based on minimization over the Nehari manifold, we establish the existence of positive ground state solutions for a large class of nonlinear terms and potentials. [ABSTRACT FROM AUTHOR]
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- 2020
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17. On nonquadratic fractional coupled elliptic systems in ℝ.
- Author
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Silva, E. D., de Albuquerque, J. C., and do Ó, J. M.
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BOUND states , *SCHRODINGER equation , *CONTINUOUS functions , *INFINITY (Mathematics) - Abstract
In this paper, we study the existence of positive solutions for the following class of nonlocal linearly coupled systems involving Schrödinger equations where denotes the fractional Laplacian, and. The coupling function is a bounded and continuous function which is related with the potentials by , for some. We deal with periodic and asymptotically periodic bounded potentials and. On the nonlinear terms and , we assume 'superlinear' at infinity and at the origin. Employing a variational approach, we obtain existence of bound and ground states solutions without assuming the well-known Ambrosetti–Rabinowitz condition on the nonlinear terms. Furthermore, we give a description of the ground states when the coupling function goes to zero in the norm. [ABSTRACT FROM AUTHOR]
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- 2019
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18. Study of thermal and optical properties of the semiconductor CdTe by photopyroelectric spectroscopy.
- Author
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de Albuquerque, J. E., de Oliveira, P. M. S., and Ferreira, S. O.
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THERMAL properties , *PROPERTIES of matter , *OPTICAL properties , *SEMICONDUCTORS , *EPITAXY , *THERMAL conductivity - Abstract
In this study, photopyroelectric spectroscopy (PPES) was used to obtain thermal and optical properties of CdTe thin films in the 300–1200 nm wavelength range. The samples studied were grown on glass or BaF2 substrates using the hot wall epitaxy technique with varying thicknesses. The normalized photopyroelectric signal intensity and its phase were independently measured as a function of wavelength λ and chopping frequency f. Equations of both the intensity and the phase of the PPES signal, taking into account the thermal and the optical characteristics of the pyroelectric detector, were used to fit the experimental results. From the fittings, we have obtained the values of thermal diffusivity coefficient α, thermal conductivity k, optical absorption coefficient, and the optical gap of CdTe. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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19. Determination of thermal and optical properties of ion implanted polyetheretherketone films by photothermal spectroscopies.
- Author
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de Albuquerque, J. E., Tavenner, E., Curry, M., Giedd, R. E., and Meredith, P.
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NITROGEN , *ION implantation , *THIN films , *PHOTOTHERMAL spectroscopy , *PROPERTIES of matter , *PHOTOACOUSTIC spectroscopy , *THERMAL diffusivity - Abstract
Photothermal spectroscopies, photopyroelectric spectroscopy and photoacoustic spectroscopy (PAS), were used to study the thermal and optical properties of untreated and N+ ion implanted polyetheretherketone (PEEK) films. The photopyroelectric (PPE) intensity signal and its phase were independently measured as a function of wavelength and chopping frequency in the saturation part of the PPE spectrum. Equations for both the intensity and the phase of the PPE signal were used to fit the experimental results. From these fits we obtained the thermal diffusivity coefficient, the thermal conductivity, and the specific heat of the samples, as well as a value for the condensed phase optical gap. Additionally, using PAS we carried out a quantitative depth profile analysis of the optical properties of the ion implanted PEEK films. Since the thermal diffusion length varies inversely with the square root of chopping modulation frequency, at high chopping frequencies surface information is obtained. At low chopping frequencies information concerning the properties of the bulk is obtained. The overall objectives of this study are to understand and quantify how ion implantation affects the thermal and optical properties of the polymer, particularly within the implant region. We find that significant changes do occur, and our results have implications for the use of ion implantation to create plastic electronic and sensor devices. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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20. On coupled systems of nonlinear Schrödinger equations with critical exponential growth
- Author
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do Ó, J. M., primary and de Albuquerque, J. C., additional
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- 2017
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21. On coupled systems of nonlinear Schrödinger equations with critical exponential growth.
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do Ó, J. M. and de Albuquerque, J. C.
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NONLINEAR Schrodinger equation , *EXISTENCE theorems , *MANIFOLDS (Mathematics) , *MAXIMUM principles (Mathematics) , *EXPONENTIAL functions - Abstract
In this paper, we prove the existence of positive ground state solutions to the following class of coupled systems involving nonlinear Schrödinger equations where the nonlinearities
and have exponential critical growth of the Trudinger-Moser type. Moreover, the coupling term satisfies . We use the minimization technique over the Nehari manifold and strong maximum principle to get a positive ground state solution. [ABSTRACT FROM AUTHOR] - Published
- 2018
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22. Role of estrogen on skeletal muscle mitochondrial function in ovariectomized rats: a time course study in different fiber types
- Author
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Cavalcanti-de-Albuquerque, J. P. A., primary, Salvador, I. C., additional, Martins, Eduarda Lopes, additional, Jardim-Messeder, D., additional, Werneck-de-Castro, J. P. S., additional, Galina, A., additional, and Carvalho, D. P., additional
- Published
- 2014
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23. Decreased Serum T3 after an Exercise Session is Independent of Glucocorticoid Peak
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Neto, R., additional, de Souza dos Santos, M., additional, Rangel, I., additional, Ribeiro, M., additional, Cavalcanti-de-Albuquerque, J., additional, Ferreira, A., additional, Cameron, L., additional, Carvalho, D., additional, and Werneck de Castro, J., additional
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- 2013
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24. Regulatory impact analysis of smart meters implementation in Brazil
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Leite, D. R. V., primary, Lamin, H., additional, de Albuquerque, J. M. C., additional, and Camargo, I. M. T., additional
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- 2012
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25. Determination of thermal and optical parameters of melanins by photopyroelectric spectroscopy
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de Albuquerque, J. E., primary, Giacomantonio, C., additional, White, A. G., additional, and Meredith, P., additional
- Published
- 2005
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26. Determination of thermal and optical parameters of the semiconductor CdTe by photopyroelectric spectroscopy
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de Albuquerque, J. E., primary, de Oliveira, P. M.S., additional, and Ferreira, S. O., additional
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- 2005
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27. Depth profile study of polyaniline films by photoacoustic spectroscopy
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de Albuquerque, J. E., primary, Balogh, D. T., additional, and Faria, R. M., additional
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- 2005
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28. Determination of physical parameters of conducting polymers by photothermal spectroscopies
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de Albuquerque, J. E., primary, Melo, W. L. B., additional, and Faria, R. M., additional
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- 2003
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29. Photothermal Spectroscopy of Polyaniline Films
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De Albuquerque, J. E., primary, Melo, W. L. B., additional, and Faria, R. M., additional
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- 2002
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30. Photopyroelectric spectroscopy of polyaniline films
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De Albuquerque, J. E., primary, Melo, W. L. B., additional, and Faria, R. M., additional
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- 2000
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31. Study of optical absorption differences of doped polyaniline films by photothermal spectroscopies.
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de Albuquerque, J. E., Melo, W. L. B., and Faria, R. M.
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DOPED semiconductors , *ABSORPTION , *THIN films , *PHOTOTHERMAL spectroscopy , *PHOTOACOUSTIC spectroscopy , *SPECTRUM analysis - Abstract
In this work, we studied the optical absorption spectral differences between doped and slightly doped polyaniline films and a derivative by photopyroelectric and photoacoustic spectroscopies. There exist great spectral differences between doped and slightly doped samples as shown by conventional optical absorption spectroscopy, but not greatly evidenced by photopyroelectric spectroscopy. The latter was applied to obtain thermal parameters such as thermal diffusivity and thermal conductivity, and as a result it showed that these thermal properties of polyaniline films are very similar for doped and slightly doped samples. Also it showed that for thicker films (about 20 μm), there are no significant optical absorption differences between them. However, for thin films both techniques showed greater optical absorption differences for doped and slightly doped samples, mainly detected by photoacoustic spectroscopy. These behaviors are in accordance with published results which is the granular metal model for polyaniline. This model explains the polyaniline polymeric matrix as formed by conductive islands in the insulating bulk material. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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32. Quantitative depth profile study of polyaniline films by photothermal spectroscopies.
- Author
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de Albuquerque, J. E., Balogh, D. T., and Faria, R. M.
- Subjects
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CONDUCTING polymers , *PHOTOTHERMAL spectroscopy , *PHOTOACOUSTIC spectroscopy , *THERMAL diffusivity , *HYDROCHLORIC acid , *SEMICONDUCTOR doping , *POLYMERIZATION - Abstract
In this study, we carried out a quantitative depth profile analysis of the optical properties of slightly and strongly doped polyaniline (PANI) films, using both photoacoustic and photopyroelectric spectroscopies. As the thermal diffusion length varies inversely to chopper modulation frequency, then at high chopping frequencies information about the sample near the surface is obtained, while at low chopping frequencies the data come from deeper within the sample. The objective of this study is to analyze how the polyaniline doping process in acidic media occurs in the polymeric chain using the photothermal techniques. The results showed that polymeric chains of the doped samples are composed of undoped regions, while polymeric chains of slightly doped samples present doped regions to a lesser degree. These conclusions are in accordance with published results in which doped PANI films exhibit a granular conductive regions in a quasi undoped matrix. In addition, the photothermal spectra showed that the doping process of PANI, in which films are dipped in hydrochloric acid solution, is more effective in the external surface of the films. [ABSTRACT FROM AUTHOR]
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- 2007
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33. Joint use of microwave and glycerol-zinc (II) acetate catalytic system in the synthesis of 2-pyridyl-2-oxazolines
- Author
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Carmona Rafaela C., Schevciw Evelyn P., de Albuquerque João L. Petrarca, Wendler Edison P., and Dos Santos Alcindo A.
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2-pyridyl-2-oxazoline ,glycerol-zinc (ii) acetate catalyst ,microwave irradiation ,Chemistry ,QD1-999 - Abstract
Glycerol combined with zinc (II) acetate catalyzed the reaction of 2-amino alcohols and 2-cyanopyridines under microwave irradiation, resulting in 2-pyridyl-2-oxazolines. Comparing the conversion to that obtained by conventional heating, a significant decrease in the reaction time was achieved. At the end of the reaction, the product was isolated and the glycerol-zinc (II) acetate catalytic system was recycled four times for the same transformation in reasonable to acceptable yields. The products were obtained in their pure form by simple filtration in a short pad of silica.
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- 2013
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34. Stromatolites of the Morrison Formation (Upper Jurassic), Union County, New Mexico--A preliminary report
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Neuhauser, Kenneth R., primary, Lucas, S. G., additional, de Albuquerque, J. Stephen, additional, Louden, Robert J., additional, Hayden, Steven N., additional, Kietzke, Kennety K., additional, Oakes, Wayne, additional, and Des Marais, David, additional
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- 1987
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35. ChemInform Abstract: MASS SPECTRA OF SUBSTITUTED Δ(2)-1,2,4-OXADIAZOLINES (I). PART 2.
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DE ALBUQUERQUE, J. F. C., primary and SRIVASTAVA, R. M., additional
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- 1981
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36. Identification of Rare Antigen-Specific T Cells from Mouse Lungs with Peptide:Major Histocompatibility Complex Tetramers.
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Shin DS, Barreto de Albuquerque J, and Moon JJ
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- Animals, Mice, Peptides immunology, Peptides chemistry, T-Lymphocytes immunology, Major Histocompatibility Complex immunology, Epitopes, T-Lymphocyte immunology, Lung immunology, Lung cytology
- Abstract
The identification and characterization of antigen-specific T cells during health and disease remains a key to improving our understanding of immune pathophysiology. The technical challenges of tracking antigen-specific T cell populations within the endogenous T cell repertoire have been greatly advanced by the development of peptide:MHC tetramer reagents. These fluorescently labeled soluble multimers of MHC class I or class II molecules complexed to antigenic peptide epitopes bind directly to T cells with corresponding T cell receptor (TCR) specificity and can, therefore, identify antigen-specific T cell populations in their native state without a requirement for a functional response induced by ex vivo stimulation. For exceedingly rare populations, tetramer-bound T cells can be magnetically enriched to increase the sensitivity and reliability of detection. As the investigation of tissue-resident T cell immunity deepens, there is a pressing need to identify antigen-specific T cells that traffic to and reside in nonlymphoid tissues. In this protocol, we present a detailed set of instructions for the isolation and characterization of antigen-specific T cells present within mouse lungs. This involves the isolation of T cells from digested lung tissue followed by a general T cell magnetic enrichment step and tetramer staining for flow cytometry analysis and sorting. The steps highlighted in this protocol utilize common techniques and readily available reagents, making it accessible for nearly any researcher engaged in mouse T cell immunology, and are highly adaptable for a variety of downstream analyses of any low frequency antigen-specific T cell population residing within the lungs.
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- 2024
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37. Optimizing Socket-Tunnel Position for Meniscal Allograft Transplantation Combined With ACL Reconstruction: A 3D Model Analysis.
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DeFroda S, Bourbon de Albuquerque J 2nd, Bezold W, Cook CR, Nuelle CW, Stannard JP, and Cook JL
- Abstract
Background: Socket-tunnel overlap during meniscal allograft transplantation (MAT) combined with anterior cruciate ligament reconstruction (ACLR) may compromise graft integrity and lead to impaired fixation and treatment failure., Purpose/hypothesis: The purpose of this study was to determine optimal socket-tunnel drilling parameters for medial and lateral MAT with concurrent ACLR using artificial tibias and computed tomography (CT) scans for 3-dimensional (3D) modeling. It was hypothesized that clinically relevant socket tunnels could be created to allow for concurrent medial or lateral MAT and ACLR without significant risk for overlap at varying tunnel guide angles., Study Design: Descriptive laboratory study., Methods: A total of 27 artificial right tibias (3 per subgroup) were allocated to 9 experimental groups based on the inclination of the socket tunnels (55°, 60°, and 65°) created for simulating medial and lateral MAT and ACLR. Five standardized socket tunnels were created for each tibia using arthroscopic guides: one for the ACL tibial insertion and one for each meniscus root insertion. CT scans were performed for all specimens and sequentially processed using computer software to produce 3D models for quantitative assessment of socket-tunnel overlap risk. Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney U tests., Results: No subgroup consistently presented significantly safer distances than other subgroups for all distances measured. Three cases (11%) and 24 cases (~90%) of tunnel overlap occurred between the ACL tunnel and tunnels for medial and lateral MAT, respectively. Most socket-tunnel overlap (25 of 27; 92.6%) occurred between sockets at depths ranging between 6.3 and 10 mm from the articular surface. For ACLR and posterior root of the lateral meniscus setting, the guide set at 65° increased socket-tunnel distances., Conclusion: When combined ACLR and MAT using socket tunnels for graft fixation is performed, the highest risk for tibial socket-tunnel overlap involves the ACLR tibial socket and the lateral meniscus anterior root socket at a depth of 6 to 10 mm from the tibial articular surface., Clinical Relevance: Setting tibial guides at 65° to the tibial articular surface with the tunnel entry point anteromedial and socket aperture location within the designated anatomic "footprint" will minimize the risk for socket-tunnel overlap., Competing Interests: One or more of the authors has declared the following potential conflict of interest or source of funding: S.D. has received research support from Arthrex; education payments from Arthrex, Encore Medical, Smith+Nephew, Medical Device Business Services, and Zimmer Biomet; nonconsulting fees from DJO and Synthes; honoraria from Encore Medical; and hospitality payments from Stryker. C.R.C. has received research support from Arthrex and Zimmer; consulting fees from Arthrex and CONMED Linvatec; nonconsulting fees from Arthrex, CONMED Linvatec, and Musculoskeletal Transplant Foundation; and royalties from Arthrex, CONMED Linvatec, and Musculoskeletal Transplant Foundation. C.W.N. has received education payments from Arthrex and Encore Orthopedics, consulting fees from Guidepoint Consulting and Arthrex, nonconsulting fees from Arthrex and Vericel, hospitality payments from Synthes GmbH, and other financial or material support from the AO Foundation. J.P.S. has received research support from Arthrex; education payments from Elite Orthopedics; consulting fees from Arthrex, DePuy Synthes/Medical Device Business Services, Orthopedic Designs North America, and Smith+Nephew; nonconsulting fees from Synthes and Medical Device Business Services; and royalties from Thieme. J.L.C. has received research support from AO Trauma, Arthrex, Collagen Matrix, DePuy Synthes, Musculoskeletal Transplant Foundation, Purina, Regenosine, and Sites Medical; consulting fees from Arthrex and Trupanion; royalties from Arthrex, Musculoskeletal Transplant Foundation, and Thieme; and was a board or committee member for the Musculoskeletal Transplant Foundation. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto., (© The Author(s) 2024.)
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- 2024
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38. Identification of mouse CD4 + T cell epitopes in SARS-CoV-2 BA.1 spike and nucleocapsid for use in peptide:MHCII tetramers.
- Author
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Bricio-Moreno L, Barreto de Albuquerque J, Neary JM, Nguyen T, Kuhn LF, Yeung Y, Hastie KM, Landeras-Bueno S, Olmedillas E, Hariharan C, Nathan A, Getz MA, Gayton AC, Khatri A, Gaiha GD, Ollmann Saphire E, Luster AD, and Moon JJ
- Subjects
- Animals, Mice, CD4-Positive T-Lymphocytes, Epitopes, T-Lymphocyte, Nucleocapsid chemistry, Peptides chemistry, Histocompatibility Antigens Class II chemistry, Spike Glycoprotein, Coronavirus chemistry, COVID-19, SARS-CoV-2 chemistry
- Abstract
Understanding adaptive immunity against SARS-CoV-2 is a major requisite for the development of effective vaccines and treatments for COVID-19. CD4
+ T cells play an integral role in this process primarily by generating antiviral cytokines and providing help to antibody-producing B cells. To empower detailed studies of SARS-CoV-2-specific CD4+ T cell responses in mouse models, we comprehensively mapped I-Ab -restricted epitopes for the spike and nucleocapsid proteins of the BA.1 variant of concern via IFNγ ELISpot assay. This was followed by the generation of corresponding peptide:MHCII tetramer reagents to directly stain epitope-specific T cells. Using this rigorous validation strategy, we identified 6 immunogenic epitopes in spike and 3 in nucleocapsid, all of which are conserved in the ancestral Wuhan strain. We also validated a previously identified epitope from Wuhan that is absent in BA.1. These epitopes and tetramers will be invaluable tools for SARS-CoV-2 antigen-specific CD4+ T cell studies in mice., Competing Interests: GG receives research funding from Merck and Moderna. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Bricio-Moreno, Barreto de Albuquerque, Neary, Nguyen, Kuhn, Yeung, Hastie, Landeras-Bueno, Olmedillas, Hariharan, Nathan, Getz, Gayton, Khatri, Gaiha, Ollmann Saphire, Luster and Moon.)- Published
- 2024
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39. Tunnel Overlap Occurs 25% of the Time With Simultaneous Anterior Cruciate Ligament Reconstruction and Lateral Meniscal Root Repair.
- Author
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DeFroda S, Bourbon de Albuquerque J 2nd, Bezold W, Cook CR, Nuelle CW, Stannard JP, and Cook JL
- Abstract
Purpose: To assess the risk of socket-tunnel overlap for posterior medial or lateral meniscal root repair combined with anterior cruciate ligament reconstruction (ACLR) using artificial tibias and computed tomography scans for 3-dimensional modeling., Methods: Artificial tibias (n = 27; n = 3/subgroup) were allocated to groups based on inclination of socket-tunnels (55°, 60°, 65°) created for posterior root of the medial meniscus (MMPR) and lateral meniscus posterior root (LMPR) repair, and ACLR. Three standardized socket-tunnels were created: one for the ACL and one for each posterior meniscal root insertion. Computed tomography scans were performed and sequentially processed using computer software to produce 3-dimensional models for assessment of socket-tunnel overlap. Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney U tests. Significance was set at P < .05., Results: The present study found no significant risk of tunnel overlap when drilling for combined ACLR and MMPR repair, whereas 7 cases of tunnel overlap occurred between ACL tunnels and LMPR (25.9% of cases). No subgroup or specific pattern of angulation consistently presented significantly safer distances than other subgroups for all distances measured., Conclusions: This study demonstrated 25.9% rate of overlap for combined LMPR repair and ACLR, compared with 0% for MMPR repair with ACLR. Lower ACL drilling angle (55 or 60°) combined with greater lateral meniscus drilling angle (65°) produced no socket-tunnel overlap., Clinical Relevance: Socket-tunnel overlap during meniscal root repair combined with ACLR may compromise graft integrity and lead to impaired fixation and treatment failure of either the ACL, the meniscus, or both. Despite this, risk for socket-tunnel overlap has not been well characterized., Competing Interests: The authors report the following potential conflicts of interest or sources of funding: S.D. reports grants from Arthrex and board member/owner/officer/committee appointments from American Orthopaedic Society for Sports Medicine, Arthroscopy, and AANA. C.R.C. reports grants and royalties or licenses from, and payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational events from Arthrex, Collagen Matrix, and the Musculoskeletal Transplant Foundation. C.W.N. reports royalties or licenses from Arthroscopy, consulting fees from Guidepoint Counseling, and payment or honoraria for lectures, presentations, speakers’ bureaus, manuscript writing, or educational events from Arthrex and Vericel, leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid: American Academy of Orthopaedic Surgeons, AANA, American Orthopaedic Society for Sports Medicine, and Arthroscopy; and other financial or nonfinancial interests from the AO Foundation. J.P.S. reports grants or contracts from Arthrex, 10.13039/100000002National Institutes of Health (National Institute of Arthritis and Musculoskeletal and Skin Diseases and Eunice Kennedy Shriver 10.13039/100000071National Institute of Child Health and Human Development), and 10.13039/100000005U.S. Department of Defense; royalties or licenses from Thieme; consulting fees from 10.13039/100007307Arthrex, DePuy, A Johnson & Johnson Company, Orthopedic Designs North America, and Smith & Nephew; and leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid: 10.13039/100005382American Orthopaedic Association, Journal of Knee Surgery, AO Foundation, Mid-America Orthopaedic Association, and AO North America. J.L.C. reports grants from AO Trauma, DePuy, A 10.13039/100004331Johnson & Johnson Company, Arthrex, the Musculoskeletal Transplant Foundation, Collagen Matrix, National Institutes of Health (National Institute of Arthritis and Musculoskeletal and Skin Diseases and Eunice Kennedy Shriver National Institute of Child Health and Human Development), Orthopaedic Trauma Association, SITES Medical, Purina, U.S. Department of Defense, and Regenosine; royalties or licenses from Arthrex, the Musculoskeletal Transplant Foundation, and Thieme; and consulting fees from Arthrex and Trupanion; leadership or fiduciary role in other board, society, committee or advocacy group, paid or unpaid: Midwest Transplant Network and Musculoskeletal Transplant Foundation. All other authors (J.B.d.A., W.B.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Full ICMJE author disclosure forms are available for this article online, as supplementary material., (© 2024 The Authors.)
- Published
- 2024
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40. Exocrine gland-resident memory CD8 + T cells use mechanosensing for tissue surveillance.
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Ruef N, Martínez Magdaleno J, Ficht X, Purvanov V, Palayret M, Wissmann S, Pfenninger P, Stolp B, Thelen F, Barreto de Albuquerque J, Germann P, Sharpe J, Abe J, Legler DF, and Stein JV
- Subjects
- Mice, Animals, Immunologic Memory, Exocrine Glands, Signal Transduction, CD8-Positive T-Lymphocytes metabolism, Virus Diseases
- Abstract
Tissue-resident CD8
+ T cells (TRM ) continuously scan peptide-MHC (pMHC) complexes in their organ of residence to intercept microbial invaders. Recent data showed that TRM lodged in exocrine glands scan tissue in the absence of any chemoattractant or adhesion receptor signaling, thus bypassing the requirement for canonical migration-promoting factors. The signals eliciting this noncanonical motility and its relevance for organ surveillance have remained unknown. Using mouse models of viral infections, we report that exocrine gland TRM autonomously generated front-to-back F-actin flow for locomotion, accompanied by high cortical actomyosin contractility, and leading-edge bleb formation. The distinctive mode of exocrine gland TRM locomotion was triggered by sensing physical confinement and was closely correlated with nuclear deformation, which acts as a mechanosensor via an arachidonic acid and Ca2+ signaling pathway. By contrast, naïve CD8+ T cells or TRM surveilling microbe-exposed epithelial barriers did not show mechanosensing capacity. Inhibition of nuclear mechanosensing disrupted exocrine gland TRM scanning and impaired their ability to intercept target cells. These findings indicate that confinement is sufficient to elicit autonomous T cell surveillance in glands with restricted chemokine expression and constitutes a scanning strategy that complements chemosensing-dependent migration.- Published
- 2023
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41. A spatio-temporal analysis investigating completeness and inequalities of global urban building data in OpenStreetMap.
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Herfort B, Lautenbach S, Porto de Albuquerque J, Anderson J, and Zipf A
- Abstract
OpenStreetMap (OSM) has evolved as a popular dataset for global urban analyses, such as assessing progress towards the Sustainable Development Goals. However, many analyses do not account for the uneven spatial coverage of existing data. We employ a machine-learning model to infer the completeness of OSM building stock data for 13,189 urban agglomerations worldwide. For 1,848 urban centres (16% of the urban population), OSM building footprint data exceeds 80% completeness, but completeness remains lower than 20% for 9,163 cities (48% of the urban population). Although OSM data inequalities have recently receded, partially as a result of humanitarian mapping efforts, a complex unequal pattern of spatial biases remains, which vary across various human development index groups, population sizes and geographic regions. Based on these results, we provide recommendations for data producers and urban analysts to manage the uneven coverage of OSM data, as well as a framework to support the assessment of completeness biases., (© 2023. The Author(s).)
- Published
- 2023
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42. Regulator of G-protein signaling 1 critically supports CD8 + T RM cell-mediated intestinal immunity.
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von Werdt D, Gungor B, Barreto de Albuquerque J, Gruber T, Zysset D, Kwong Chung CKC, Corrêa-Ferreira A, Berchtold R, Page N, Schenk M, Kehrl JH, Merkler D, Imhof BA, Stein JV, Abe J, Turchinovich G, Finke D, Hayday AC, Corazza N, and Mueller C
- Subjects
- Animals, Mice, Protein Subunits metabolism, T-Lymphocyte Subsets, CD8-Positive T-Lymphocytes, GTP-Binding Proteins metabolism, Listeria monocytogenes
- Abstract
Members of the Regulator of G-protein signaling (Rgs) family regulate the extent and timing of G protein signaling by increasing the GTPase activity of Gα protein subunits. The Rgs family member Rgs1 is one of the most up-regulated genes in tissue-resident memory (T
RM ) T cells when compared to their circulating T cell counterparts. Functionally, Rgs1 preferentially deactivates Gαq, and Gαi protein subunits and can therefore also attenuate chemokine receptor-mediated immune cell trafficking. The impact of Rgs1 expression on tissue-resident T cell generation, their maintenance, and the immunosurveillance of barrier tissues, however, is only incompletely understood. Here we report that Rgs1 expression is readily induced in naïve OT-I T cells in vivo following intestinal infection with Listeria monocytogenes -OVA. In bone marrow chimeras, Rgs1-/- and Rgs1+/+ T cells were generally present in comparable frequencies in distinct T cell subsets of the intestinal mucosa, mesenteric lymph nodes, and spleen. After intestinal infection with Listeria monocytogenes -OVA, however, OT-I Rgs1+/+ T cells outnumbered the co-transferred OT-I Rgs1- /- T cells in the small intestinal mucosa already early after infection. The underrepresentation of the OT-I Rgs1-/- T cells persisted to become even more pronounced during the memory phase (d30 post-infection). Remarkably, upon intestinal reinfection, mice with intestinal OT-I Rgs1+/+ TRM cells were able to prevent the systemic dissemination of the pathogen more efficiently than those with OT-I Rgs1-/- TRM cells. While the underlying mechanisms are not fully elucidated yet, these data thus identify Rgs1 as a critical regulator for the generation and maintenance of tissue-resident CD8+ T cells as a prerequisite for efficient local immunosurveillance in barrier tissues in case of reinfections with potential pathogens., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 von Werdt, Gungor, Barreto de Albuquerque, Gruber, Zysset, Kwong Chung, Corrêa-Ferreira, Berchtold, Page, Schenk, Kehrl, Merkler, Imhof, Stein, Abe, Turchinovich, Finke, Hayday, Corazza and Mueller.)- Published
- 2023
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43. Microbial uptake in oral mucosa-draining lymph nodes leads to rapid release of cytotoxic CD8 + T cells lacking a gut-homing phenotype.
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Barreto de Albuquerque J, Altenburger LM, Abe J, von Werdt D, Wissmann S, Martínez Magdaleno J, Francisco D, van Geest G, Ficht X, Iannacone M, Bruggmann R, Mueller C, and Stein JV
- Subjects
- Lymph Nodes, Phenotype, T-Lymphocytes, Cytotoxic, CD8-Positive T-Lymphocytes, Mouth Mucosa
- Abstract
The gastrointestinal (GI) tract constitutes an essential barrier against ingested microbes, including potential pathogens. Although immune reactions are well studied in the lower GI tract, it remains unclear how adaptive immune responses are initiated during microbial challenge of the oral mucosa (OM), the primary site of microbial encounter in the upper GI tract. Here, we identify mandibular lymph nodes (mandLNs) as sentinel lymphoid organs that intercept ingested Listeria monocytogenes (Lm). Oral Lm uptake led to local activation and release of antigen-specific CD8
+ T cells that constituted most of the early circulating effector T cell (TEFF ) pool. MandLN-primed TEFF disseminated to lymphoid organs, lung, and OM and contributed substantially to rapid elimination of target cells. In contrast to CD8+ TEFF generated in mesenteric LN (MLN) during intragastric infection, mandLN-primed TEFF lacked a gut-seeking phenotype, which correlated with low expression of enzymes required for gut-homing imprinting by mandLN stromal and dendritic cells. Accordingly, mandLN-primed TEFF decreased Lm burden in spleen but not MLN after intestinal infection. Our findings extend the concept of regional specialization of immune responses along the length of the GI tract, with CD8+ TEFF generated in the upper GI tract displaying homing profiles that differ from those imprinted by lymphoid tissue of the lower GI tract.- Published
- 2022
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44. The effect of a mindfulness-based intervention on executive, behavioural and socio-emotional competencies in very preterm young adolescents.
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Siffredi V, Liverani MC, Hüppi PS, Freitas LGA, De Albuquerque J, Gimbert F, Merglen A, Meskaldji DE, Borradori Tolsa C, and Hà-Vinh Leuchter R
- Subjects
- Adolescent, Adolescent Behavior psychology, Adolescent Development, Child, Child Behavior psychology, Child Development, Child, Preschool, Female, Humans, Infant, Infant, Newborn, Male, Premature Birth psychology, Emotions, Executive Function, Infant, Extremely Premature, Mindfulness methods, Premature Birth epidemiology, Social Behavior
- Abstract
Very preterm (VPT) children and adolescents show executive, behavioural and socio-emotional difficulties that persists into adulthood. This study aims to assess the effectiveness of a mindfulness-based intervention (MBI) in improving these competencies in VPT young adolescents using a randomised controlled trial design. 56 young adolescents aged 10-14 years, born before 32 gestational weeks, were randomly assigned to an "intervention" or a "waiting" group and completed an 8-week MBI in a cross-over design. Executive, behavioural and socio-emotional competencies were assessed at three different time points via parent and self-reported questionnaires, neuropsychological testing and computerised tasks. The data were analysed using an intention-to-treat approach with linear regression modelling. Our findings show a beneficial effect of MBI on executive, behavioural and socio-emotional competencies in VPT young adolescents measured by parent questionnaires. Increased executive competencies were also observed on computerised task with enhanced speed of processing after MBI. Two subgroups of participants were created based on measures of prematurity, which revealed increased long-term benefits in the moderate-risk that were not observed in the high-risk subgroups of VPT young adolescents. MBI seems a valuable tool for reducing detrimental consequences of prematurity in young adolescents, especially regarding executive, behavioural and socio-emotional difficulties.Clinical Trial Registration ClinicalTrials, NCT04638101. Registered 20 November 2020-Retrospectively registered, https://clinicaltrials.gov/show/NCT04638101 ., (© 2021. The Author(s).)
- Published
- 2021
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45. Improving executive, behavioural and socio-emotional competences in very preterm young adolescents through a mindfulness-based intervention: Study protocol and feasibility.
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Siffredi V, Liverani MC, Smith MM, Meskaldji DE, Stuckelberger-Grobéty F, Freitas LGA, De Albuquerque J, Savigny E, Gimbert F, Hüppi PS, Merglen A, Borradori Tolsa C, and Leuchter RH
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- Adolescent, Child, Emotions, Feasibility Studies, Humans, Infant, Extremely Premature, Infant, Newborn, Randomized Controlled Trials as Topic, Surveys and Questionnaires, Mindfulness methods
- Abstract
Background: Very preterm (VPT) children and adolescents show executive, behavioural and socio-emotional difficulties that persist into adulthood. Despite the promising role of mindfulness-based intervention (MBI) in improving theses competences in children and adolescents, the effectiveness of an MBI has not been assessed in a VPT population so far., Aims: To describe the protocol and to evaluate the feasibility and acceptability of a clinical trial on an 8-week MBI program to enhance executive and socio-emotional competences in a cohort of VPT young adolescents., Study Design: A randomised controlled trial (RCT) and a pre-post intervention designs., Participants: 164 VPT young adolescents from 10 to 14 years old, born before 32 gestational weeks, without major intellectual, sensory or physical impairments, and attending mainstream school, were invited to participate in an 8-week MBI program., Outcome Measures: Completion rate of the study was recorded. Acceptability, satisfaction and attendance measures of the MBI were collected using self-reported questionnaires and registration of attendance., Results: Of the 63 participants who were enrolled in the study (38.2% of families invited to participate), 52 (82.5%) completed all assessments. Acceptability was high as shown by the high attendance rate in the sessions and the feedback evaluation questionnaire., Conclusions: Our findings suggest that an MBI is feasible to implement and show a high acceptability among participants. The use of an RCT design in our study constitutes the gold standard for testing the efficacy of such intervention in VPT young adolescents. If effective, the MBI program could potentially be a valuable tool for improving executive and socio-emotional competences in the vulnerable VPT population., Trial Registration: ClinicalTrials, NCT04638101. Registered 19 November 2020 - retrospectively registered, https://clinicaltrials.gov/show/NCT04638101., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2021
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46. Tissue-Resident T Cells in Chronic Relapsing-Remitting Intestinal Disorders.
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Barreto de Albuquerque J, Mueller C, and Gungor B
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- Animals, Cell Differentiation, Chronic Disease, Host-Pathogen Interactions, Humans, Immunologic Memory, Inflammation Mediators metabolism, Inflammatory Bowel Diseases metabolism, Inflammatory Bowel Diseases pathology, Intestinal Mucosa metabolism, Intestinal Mucosa pathology, Lymphocyte Activation, Phenotype, Recurrence, Signal Transduction, T-Lymphocytes, Regulatory metabolism, Immunity, Cellular, Inflammatory Bowel Diseases immunology, Intestinal Mucosa immunology, T-Lymphocytes, Regulatory immunology
- Abstract
Tissue-resident memory T (T
RM ) cells critically contribute to the rapid immunoprotection and efficient immunosurveillance against pathogens, particularly in barrier tissues, but also during anti-tumor responses. However, the involvement of TRM cells also in the induction and exacerbation of immunopathologies, notably in chronically relapsing auto-inflammatory disorders, is becoming increasingly recognized as a critical factor. Thus, TRM cells may also represent an attractive target in the management of chronic (auto-) inflammatory disorders, including multiple sclerosis, rheumatoid arthritis, celiac disease and inflammatory bowel diseases. In this review, we focus on current concepts of TRM cell biology, particularly in the intestine, and discuss recent findings on their involvement in chronic relapsing-remitting inflammatory disorders. Potential therapeutic strategies to interfere with these TRM cell-mediated immunopathologies are discussed.- Published
- 2021
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47. The evolution of humanitarian mapping within the OpenStreetMap community.
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Herfort B, Lautenbach S, Porto de Albuquerque J, Anderson J, and Zipf A
- Abstract
In the past 10 years, the collaborative maps of OpenStreetMap (OSM) have been used to support humanitarian efforts around the world as well as to fill important data gaps for implementing major development frameworks such as the Sustainable Development Goals. This paper provides a comprehensive assessment of the evolution of humanitarian mapping within the OSM community, seeking to understand the spatial and temporal footprint of these large-scale mapping efforts. The spatio-temporal statistical analysis of OSM's full history since 2008 showed that humanitarian mapping efforts added 60.5 million buildings and 4.5 million roads to the map. Overall, mapping in OSM was strongly biased towards regions with very high Human Development Index. However, humanitarian mapping efforts had a different footprint, predominantly focused on regions with medium and low human development. Despite these efforts, regions with low and medium human development only accounted for 28% of the buildings and 16% of the roads mapped in OSM although they were home to 46% of the global population. Our results highlight the formidable impact of humanitarian mapping efforts such as post-disaster mapping campaigns to improve the spatial coverage of existing open geographic data and maps, but they also reveal the need to address the remaining stark data inequalities, which vary significantly across countries. We conclude with three recommendations directed at the humanitarian mapping community: (1) Improve methods to monitor mapping activity and identify where mapping is needed. (2) Rethink the design of projects which include humanitarian data generation to avoid non-sustainable outcomes. (3) Remove structural barriers to empower local communities and develop capacity.
- Published
- 2021
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48. Immune synapse instructs epigenomic and transcriptomic functional reprogramming in dendritic cells.
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Alcaraz-Serna A, Bustos-Morán E, Fernández-Delgado I, Calzada-Fraile D, Torralba D, Marina-Zárate E, Lorenzo-Vivas E, Vázquez E, Barreto de Albuquerque J, Ruef N, Gómez MJ, Sánchez-Cabo F, Dopazo A, Stein JV, Ramiro A, and Sánchez-Madrid F
- Subjects
- Cell Movement, Dendritic Cells, Lymph Nodes, Receptors, CCR7, Synapses, Epigenomics, Transcriptome
- Abstract
Understanding the fate of dendritic cells (DCs) after productive immune synapses (postsynaptic DCs) with T cells during antigen presentation has been largely neglected in favor of deciphering the nuances of T cell activation and memory generation. Here, we describe that postsynaptic DCs switch their transcriptomic signature, correlating with epigenomic changes including DNA accessibility and histone methylation. We focus on the chemokine receptor Ccr7 as a proof-of-concept gene that is increased in postsynaptic DCs. Consistent with our epigenomic observations, postsynaptic DCs migrate more efficiently toward CCL19 in vitro and display enhanced homing to draining lymph nodes in vivo. This work describes a previously unknown DC population whose transcriptomics, epigenomics, and migratory capacity change in response to their cognate contact with T cells., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)
- Published
- 2021
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49. Impact of the societal response to COVID-19 on access to healthcare for non-COVID-19 health issues in slum communities of Bangladesh, Kenya, Nigeria and Pakistan: results of pre-COVID and COVID-19 lockdown stakeholder engagements.
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Ahmed SAKS, Ajisola M, Azeem K, Bakibinga P, Chen YF, Choudhury NN, Fayehun O, Griffiths F, Harris B, Kibe P, Lilford RJ, Omigbodun A, Rizvi N, Sartori J, Smith S, Watson SI, Wilson R, Yeboah G, Aujla N, Azam SI, Diggle PJ, Gill P, Iqbal R, Kabaria C, Kisia L, Kyobutungi C, Madan JJ, Mberu B, Mohamed SF, Nazish A, Odubanjo O, Osuh ME, Owoaje E, Oyebode O, Porto de Albuquerque J, Rahman O, Tabani K, Taiwo OJ, Tregonning G, Uthman OA, and Yusuf R
- Subjects
- Africa South of the Sahara, Asia, Western, Betacoronavirus, COVID-19, Humans, Public Health, SARS-CoV-2, Stakeholder Participation, Coronavirus Infections, Health Services Accessibility, Pandemics, Pneumonia, Viral, Poverty Areas
- Abstract
Introduction: With COVID-19, there is urgency for policymakers to understand and respond to the health needs of slum communities. Lockdowns for pandemic control have health, social and economic consequences. We consider access to healthcare before and during COVID-19 with those working and living in slum communities., Methods: In seven slums in Bangladesh, Kenya, Nigeria and Pakistan, we explored stakeholder perspectives and experiences of healthcare access for non-COVID-19 conditions in two periods: pre-COVID-19 and during COVID-19 lockdowns., Results: Between March 2018 and May 2020, we engaged with 860 community leaders, residents, health workers and local authority representatives. Perceived common illnesses in all sites included respiratory, gastric, waterborne and mosquitoborne illnesses and hypertension. Pre-COVID, stakeholders described various preventive, diagnostic and treatment services, including well-used antenatal and immunisation programmes and some screening for hypertension, tuberculosis, HIV and vectorborne disease. In all sites, pharmacists and patent medicine vendors were key providers of treatment and advice for minor illnesses. Mental health services and those addressing gender-based violence were perceived to be limited or unavailable. With COVID-19, a reduction in access to healthcare services was reported in all sites, including preventive services. Cost of healthcare increased while household income reduced. Residents had difficulty reaching healthcare facilities. Fear of being diagnosed with COVID-19 discouraged healthcare seeking. Alleviators included provision of healthcare by phone, pharmacists/drug vendors extending credit and residents receiving philanthropic or government support; these were inconsistent and inadequate., Conclusion: Slum residents' ability to seek healthcare for non-COVID-19 conditions has been reduced during lockdowns. To encourage healthcare seeking, clear communication is needed about what is available and whether infection control is in place. Policymakers need to ensure that costs do not escalate and unfairly disadvantage slum communities. Remote consulting to reduce face-to-face contact and provision of mental health and gender-based violence services should be considered., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2020
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50. Biological Evaluation of Arylsemicarbazone Derivatives as Potential Anticancer Agents.
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Nascimento da Cruz AC, Brondani DJ, I Talo de Santana T, Oliveira da Silva L, da Oliveira Borba EF, de Faria AR, Ferreira Cavalcanti de Albuquerque J, Piessard S, Matos Ximenes R, Baratte B, Bach S, Ruchaud S, Bezerra Mendonça Junior FJ, Bazin MA, Montenegro Rabello M, Hernandes MZ, Marchand P, and Gonçalves da Silva T
- Abstract
Fourteen arylsemicarbazone derivatives were synthesized and evaluated in order to find agents with potential anticancer activity. Cytotoxic screening was performed against K562, HL-60, MOLT-4, HEp-2, NCI-H292, HT-29 and MCF-7 tumor cell lines. Compounds 3c and 4a were active against the tested cancer cell lines, being more cytotoxic for the HL-60 cell line with IC
50 values of 13.08 μM and 11.38 μM, respectively. Regarding the protein kinase inhibition assay, 3c inhibited seven different kinases and 4a strongly inhibited the CK1δ/ε kinase. The studied kinases are involved in several cellular functions such as proliferation, migration, cell death and cell cycle progression. Additional analysis by flow cytometry revealed that 3c and 4a caused depolarization of the mitochondrial membrane, suggesting apoptosis mediated by the intrinsic pathway. Compound 3 c induced arrest in G1 phase of the cell cycle on HL-60 cells, and in the annexin V assay approximately 50% of cells were in apoptosis at the highest concentration tested (26 μM). Compound 4a inhibited cell cycle by accumulation of abnormal postmitotic cells at G1 phase and induced DNA fragmentation at the highest concentration (22 μM).- Published
- 2019
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