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In the teleparallel $f(T)$ gravity scenario, we consider a five-dimensional thick brane. This scenario is interesting because this theory can provide explanations for inflation, radiation, and dark matter under certain conditions. It is convenient to assume, for our study, a polynomial profile of the function $f(T)$. Indeed, some polynomial profiles can produce internal structures for which a brane splitting occurs. For functions $f(T)$ with this capability, geometrically contracted matter field configurations are obtained. These contractions of the matter field for the profiles of $f(T)$ reproduce compact-like settings. To complement the study, we analyze the stability of the brane using the concept of Configurational Entropy (CE). The CE arguments are interesting because they tell us the most stable and likely configurations from the brane in this gravitational background. Therefore, we can indicate the best profile of the function $f(T)$., Comment: 22 pages, 15 captioned figures. To appear in International Journal of Modern Physics D

The thick brane scenario built on the f(T,B) teleparallel gravity theory was considered for the study of phase transitions, internal structures, and new classes of solutions in a model. In this theory, T denotes the torsion scalar, and B is a boundary term. An interesting result was observed when brane splitting occurs, i. e., internal structures in the model arise as a consequence of the appearance of new domain walls in the theory. In fact, this preliminary result influences the profile of the matter field (from kink to multi-kink) so that for appropriate values of the parameters $k_{1,2}$ multiple phase transitions are identified. To perform this analysis, the Differential Configurational Entropy (DCE) which has the ability to predict the existence of phase transitions through critical points was used. Furthermore, the DCE is able to select the most stable solutions since it gives us details about the informational content of the field settings., 20 pages,10 captioned figures. Updated version to match accepted one in IJMPD. Title changed. Minor modifications

In this research article, we use the Shannon's formalism to investigate the quantum information entropy of a particle trapped by the Aharonov-Bohm-type effect. For quantum information study, it is necessary to investigate the eigenstates of the quantum system, i. e., the wave functions and energies of the quantum states. We assumed that the particle is in principle, confined in a cylindrical box in the presence of an Aharonov-Bohm-type effect due to dislocation defect. Analysis of the quantum information entropy, reveals that the dislocation influences the eigenstates and, consequently, the quantum information of the system., 15 pages, 2 captioned figures. Title changed. Enhanced version to appear in Physica Scripta

The topological structures of a $\phi^6$ theory with multi-field are studied. The $\phi^6$ theory is interesting because it is a theory that allows the shrinkage of topological structures generating double-kink or even multi-kink configurations. In this work, we consider and study the solutions of a two real scalar fields model. To reach our purpose, we investigate the BPS properties of the fields using the approach proposed by Bogomol'nyi-Prasad-Sommerfield. Using the BPS energy density, the differential configurational entropy (DCE) of the BPS structures is studied. The result of the DCE indicates the most likely field configuration of one of the topological sectors of the model., Comment: 15 pages, 7 captioned figures. To appear in Europhysics Letters

We introduced a generalized Maxwell-Higgs model in a $(3+1)$ isotropic spacetime, and we found their stationary solutions using the BPS approach in curved spacetime. In order to investigate the compact-like vortices, we assume a particular choice for the generalization term. The model is controlled by a potential driven by a single real parameter that can be used to change the vortex solutions profile as they approach their bound values. Resembling some flat spacetime vortex solutions, our model tends to compress the vortices when the parameter $l$ increases. Through numerical analysis, we also show the energy behavior and the magnetic field of the model., 17 pages, 5 figures. To appear in Annals of Physics

A Majorana fermion is the single fermionic particle that is its own antiparticle. Its dynamics is determined by the Majorana equation, where the spinor field is by definition equal to its charge-conjugate field. In this paper, we investigated Shannon's entropy of linear Majorana fermions to understand how this quantity is modified due to an external potential of the linear type linear. Subsequently, we turn our attention to the construction of an ensemble of these Majorana particles to study the thermodynamic properties of the model. Finally, we show how Shannon's entropy and thermodynamic properties are modified under the linear potential action., 26 pages, 7 figures

In this paper, we explore the five-dimensional f(T,B) teleparallel modified gravity with f_1(T,B)=T+k_1B^{n_1} and f_2(T,B)=B+k_2T^{n_2} in the brane scenario. Asymptotically, the bulk geometry converges to an AdS_5 spacetime whose cosmological constant is produced by parameters that control torsion and boundary term. The analysis of the energy density condition reveals a splitting brane process satisfying the weak and strong energy conditions for some values of the parameters n_{1,2} and k_{1,2}. In addition, we investigate the behavior of the gravitational perturbations in this scenario. In the bulk, the torsion keeps a gapless non-localizable, and stable tower of massive modes. Inside the brane core, the torsion produces new barriers and potential wells, leading to small amplitude massive modes and a massless mode localized for some values of the parameters n_{1,2} and k_{1,2}., 26 pages, 30 figures. Updated to match the published version to appear in Physical Review D. Some modifications in the text in order to clarify arguments but the results are unchanged

In the context of non-relativistic quantum mechanics, we investigated Shannon's entropy of a non-Hermitian system to understand how this quantity is modified with the cyclotron frequency. Subsequently, we turn our attention to the construction of an ensemble of these spinless particles in the presence of a uniform magnetic field. Then, we study the thermodynamic properties of the model. Finally, we show how Shannon's entropy and thermodynamic properties are modified with the action of the magnetic field., 19 pages, 14 figures. To appear in International Journal of Quantum Chemistry

In this paper, we study the thick brane scenario constructed in the recently proposed $f(T,\mathcal{T})$ theories of gravity, where $T$ is called the torsion scalar, and $\mathcal{T}$ is the trace of the energy-momentum tensor. We use the first-order formalism to find analytical solutions for models that include a scalar field as a source. In particular, we describe two interesting cases in which, in the first, we obtain a double-kink solution, which generates a splitting in the brane. In the second case, proper management of a kink solution obtained generates a splitting in the brane intensified by the torsion parameter, evinced by the energy density components satisfying the weak and strong energy conditions. In addition, we investigate the behavior of the gravitational perturbations in this scenario. The parameters that control the torsion and the trace of the energy-momentum tensor tend to shift the massive modes to the core of the brane, keeping a gapless non-localizable and stable tower of massive modes and producing more localized massless modes., Comment: 31 pages, 49 figures. Revised version to match published version in EPJC

In order to investigate possible topological vortex structures in generalized models, we developed a perturbative generation approach for scalar-vector theories. We demonstrate explicitly that the dielectric permeability functions must have a nonpolynomial shape, i. e., the form of the logarithmic function. Basing on this result, we built models in $(2+1)D$ with logarithmic dielectric permeability in order to investigate the presence of topological vortex structures in a Maxwell model. This type of scalar-vector models is important because they can generate stationary field solutions in theories describing the dynamics of the scalar field. As examples, we chose models of the complex scalar field coupled to the Maxwell field. Subsequently, we investigated the model's Bogomol'nyi equations to describe the field configurations. Then, we demonstrate numerically, for an ansatz with rotational symmetry, that the solutions of the complex scalar field generating minimum energy configurations are topological structures depending on the parameters obtained in the perturbative generation of the vector-scalar theory., Comment: 26 pages, 13 figures

In the context of non-relativistic quantum mechanics, we use information theory to study Shannon’s entropy of a non-Hermitian system and understand how the information is modified with the cyclotron frequency. Subsequently, we turn our attention to the construction of an ensemble of these spinless particles in the presence of a uniform magnetic field. Then, we study the thermodynamic properties of the model. Finally, we show how information and thermodynamic properties are modified with the action of the magnetic field.Keywords: Non-relativistic Quantum Mechanics; Quantum Information; Shannon Entropy.

In this work, we propose an exponentially generalized Abelian model. We investigated the presence of vortex structures in models coupled to Maxwell and Chern-Simons fields. We chose to investigate the dynamics of the complex scalar field in models coupled separately to the Maxwell term and the Chern-Simons term. For this, we analyze the Bogomol'nyi equations in both cases to describe the static field configurations. An interesting result appears when we note that scalar field solutions generate degenerate minimum energy configurations by a factor of $\nu^{2}$ in Maxwell's case. On the other hand, in the case of Chern-Simons, the solutions in this sector are degenerate by a factor of $\kappa\nu^{2}/a_{s}$. Finally, we solve the Bogomol'nyi equations numerically and discuss our results., Comment: 17 pages. 5 figures. To appear in Europhysics Letters

We investigate the presence of vortex structures in a Maxwell model with a logarithmic generalization. This generalization becomes important because it generates stationary field solutions in models that describe the dynamics of a scalar field. In this work, we will choose to investigate the dynamics of the complex scalar field with the gauge field governed by Maxwell term. For this, we will investigate the Bogomol'nyi equations to describe the static field configurations. Then, we show numerically that the complex scalar field solutions that generate minimum energy configurations have internal structures. Finally, assuming a planar vision, the magnetic field and the density energy show the interesting feature of the ringlike vortex., Comment: 15 pages, 6 figures. To appear in Europhysics Letters

In this paper, we investigate the thermodynamic properties of an Aharonov-Bohm (AB) quantum ring in a heat bath for both relativistic and non-relativistic cases. For accomplishing this, we used the partition function which was obtained numerically using the Euler-Maclaurin formula. In particular, we determined the energy spectra as well as the behavior of the main thermodynamic functions of the canonical ensemble, namely, the Helmholtz free energy, the mean energy, the entropy and the heat capacity. The so-called Dulong-Petit law was verified only for the relativistic case. We noticed that in the low energy regime, the relativistic thermodynamic functions are reduced to the non-relativistic case as well., Comment: 12 pages, 8 figures

In this work, we study emission correlations in Rainbow Gravity (RG) black holes known to have black hole remnants. Non-thermal corrections are responsible for generating non-zero correlations between particle emission events during the black hole evaporation process. With this in mind, we calculate the temperatures considering back-reaction effects. Then, we obtain the correlations between emission events for a RG metric proposed by Magueijo and Smolin. We also discuss through a numerical analysis the emission correlations behavior in the last stages of evaporation of the black hole., Comment: 17 pages, 5 figures. Updated to match the published version to appear in Annals of Physics. Some modifications in the text but the results are unchanged

In this work, we investigate the solutions of vortices in the O ( 3 ) -sigma model with the gauge field governed by the Chern–Simons term and subject to a hyperbolic self-dual potential. We show that this model admits both topological and nontopological soliton solutions. Employing numerical analysis, we realize that the topological solutions of the model can be transformed into compacton-like solutions. On the other hand, after modifying the model by the introduction of a dielectric constant, an exciting feature appears; namely, the nontopological solutions can be transformed into kink-like solutions through the numerical variation of the dielectric constant. Furthermore, we discuss the degeneracy for the topological solitons in a given sector. Finally, we present the numerical solutions of the first model.

In this work, we investigated the existence of compacton-like configuration in the O(3)-sigma model. We consider a minimally coupled O(3)-sigma model with a gauge field governed by a generalized Chern-Simons term. Contrary to that established in the literature, we impose a new set of boundary conditions and, we find solutions of the variable fields and the respective energy density in the Bogomol'nyi limit. On the other hand, the introduction of a parameter $\omega$ in the Chern-Simons term can be adjusted to leads to finite-energy solutions of the model. Moreover, compact-like structures were studied with the evolution of this $\omega$ generalized Chern-Simons term., Comment: 12 pages, 7 figures

Nowadays, in Brazil there is a large energy potential that comes from hydro mineral sources, which most part of the electricity consumed comes from this source. According to this, it is important emphasize that the decision-making related with planning of the operation of the reservoirs of hydroelectric plants has been done based mainly on preview knowledge of the flow. Thereby, this work aims to conduct an exploratory study about the Artificial Neural Networks type MLP to estimate which is the best setting to perform the stream flow forecast. This study was applied to the Rio Grande basin, in addition, with the achieved results, it was possible to observe that the search of appropriate parameters shows significant gains in the execution of the forecasts and can to reduce the error level obtained.

In order to define the roles of the K-ras and p53 genes in the development of lung cancer, especially in young adults, we compared the clinicopathological features of the patients between younger (or = 45 years, n = 47) and older (55 years, n = 50) groups. The gene alterations were examined by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method. The K-ras gene alterations were detected only in adenocarcinomas, and the p53 gene alterations in all histologic types of lung cancer. There were no significant differences in the frequency of both K-ras and p53 gene alterations between the younger and older groups (9 vs. 11%, 36 vs. 32%). In the younger group, but not in the older one, the percentage for smokers was significantly higher in the p53 gene alteration-positive group than for the negative group (65 vs. 30%). As to the prognosis, there were no significant differences between the p53 gene alteration-positive and -negative cases in both the younger and older groups as well as in all subjects, while a tendency of poorer prognosis was observed in K-ras gene alteration-positive cases than for the -negative ones with adenocarcinomas. These results suggest that (1) the K-ras and p53 gene alterations would have no special roles in terms of the lung carcinogenesis in young adults; (2) a positive relationship between smoking and p53 gene alteration would exist in young adults with lung cancer, and (3) K-ras gene alteration would become a prognostic factor in lung cancer.

The potential utility of flow cytometric (FCM) analysis in routine diagnostic cytology for effusions was assessed with 104 samples from body cavity fluids. Conventional cytology showed no positivity (0/33) for effusions from patients with non-malignant diseases, and 45% positivity (38/71) for effusions from patients with malignant diseases. Conversely, FCM showed no positivity (aneuploid) (0/33) for effusions from patients with non-malignant diseases, and 18% positivity (13/71) with malignant diseases. In 13 cases examined, 8 cases (62%) showed an identical DNA ploidy pattern between effusion site and primary site. FCM showed positivity in four cytologically negative samples (3 malignant lymphomas and 1 clear cell carcinoma). In cases with malignant lymphoma, conventional cytology showed 40% positivity (4/10) and FCM 60% (6/10) positivity. These results indicate that DNA analysis of cells in malignant effusions does not have a diagnostic value as a routine test, but it may have in cases of malignant lymphoma.

Clinicopathological features of surgically-treated peripheral T1 adenocarcinoma of the lung were compared between 30 females and 26 males, and the following sex differences were observed; 1) Females were younger than males, 2) There was a higher percentage of smokers among males, 3) The acinar histologic subtype was less frequently found in females, 4) Well differentiated tumors were more frequently found in females, 5) K-ras gene mutations were observed only in males, 6) Prognosis was slightly better in females. As to other factors such as N-factor, tumor ploidy or central fibrosis, there was no statistical difference between the two groups. Although we were not able to explain the causes for the above sex differences, it was speculated that smoking was mainly responsible for them.

The effect of various nitrogen sources on growth and efficiency parameters of Ascobolus furfuraceus was investigated. As nitrogen sources, sodium nitrate and nitrite, inorganic ammonium salts and nitrated organic compounds have been used. The results showed that all of them could be used by the fungus, with the exceptions of sodium nitrite and ammonium oxalate. Good correlation was observed among the growth parameters, the 'economic coefficients' of uptake and internal conversion of sources, and the specific respiration rates. The best nitrogen source - estimated as growth and efficiency parameters - was ammonium carbonate in the culture conditions used. The possibility of heterotrophic carbon fixation is discussed.

Ascobolus furfuraceus mycelium showed morphological variations when grown with different nitrogen sources. The hyphae were compared using as parameters cell diameter and length, branching and vacuolization. The variations in cell size, vacuolar area and branching, in response to the nitrogen source, suggest that the nitrogen régime plays a controlling role in the growth of the mycelium as well as in the morphogenesis of the cells. The results are discussed in relation to previous data on the metabolic efficiency of the fungus.