Spacetime quantization induced by axial currents

In the present contribution we show that the introduction of a conserved axial current in electrodynamics can explain the quantization of electric charge, inducing at the same time a dynamical quantization of spacetime.Comment: To appear in Chaos Solitons & Fractal

Electromagnetic Structure of the Pion

In this work, we analyze the electromagnetic structure of the pion. We calculate its electromagnetic radius and electromagnetic form factor in low and intermediate momentum range. Such observables are determined by means of a theoretical model that takes into account the constituent quark and antiquark of the pion within the formalism of light-front field theory. In particular, we consider a nonsymmetrical vertex in this model, with which we calculate the electromagnetic form factor of the pion in an optimized way, so that we obtain a value closer to the experimental charge radius of the pion. The theoretical calculations are also compared with the most recent experimental data involving the pion electromagnetic form factor and the results show very good agreement.Comment: Paper with 4 pages, 1 figure, presented in XII HADRON PHYSICS Conference - to appear in AIP Conference Proceeding

Calculation of excited polaron states in the Holstein model

An exact diagonalization technique is used to investigate the low-lying excited polaron states in the Holstein model for the infinite one-dimensional lattice. For moderate values of the adiabatic ratio, a new and comprehensive picture, involving three excited (coherent) polaron bands below the phonon threshold, is obtained. The coherent contribution of the excited states to both the single-electron spectral density and the optical conductivity is evaluated and, due to the invariance of the Hamiltonian under the space inversion, the two are shown to contain complementary information about the single-electron system at zero temperature. The chosen method reveals the connection between the excited bands and the renormalized local phonon excitations of the adiabatic theory, as well as the regime of parameters for which the electron self-energy has notable non-local contributions. Finally, it is shown that the hybridization of two polaron states allows a simple description of the ground and first excited state in the crossover regime.Comment: 12 pages, 9 figures, submitted to PR

Oxidation of potato starch with different sodium hypochlorite concentrations and its effect on biodegradable films

AbstractThe objective of this study was to evaluate the effects of oxidation with sodium hypochlorite at different concentrations of active chlorine (0.5, 1.0 and 1.5 g/100 g) on the physicochemical, morphological, pasting, thermal and gel texture properties of potato starch. The native and oxidized starches were used in different concentrations (3.0, 4.0 and 5.0 g starch/100 mL) for the preparation of biodegradable films using glycerol as plasticizer. The films were evaluated for their mechanical properties, color, water solubility and permeability of water vapor. The degree of oxidation potato starches was more intense as there was an increased concentration of active chlorine in the reaction. Films made with oxidized starch with the highest level of active chlorine had lower tensile strength when compared to native starch films. Also, these films had a lower water solubility and water vapor permeability as compared to the native starch films

Structural, morphological, and physicochemical properties of acetylated high-, medium-, and low-amylose rice starches

AbstractThe high-, medium-, and low-amylose rice starches were isolated by the alkaline method and acetylated by using acetic anhydride for 10, 30, and 90min of reaction. The degree of substitution (DS), the Fourier-transformed infrared spectroscopy (FTIR), the X-ray diffractograms, the thermal, morphological, and pasting properties, and the swelling power and solubility of native and acetylated starches were evaluated. The DS of the low-amylose rice starch was higher than the DS of the medium- and the high-amylose rice starches. The introduction of acetyl groups was confirmed by FTIR spectroscopy. The acetylation treatment reduced the crystallinity, the viscosity, the swelling power, and the solubility of rice starch; however, there was an increase in the thermal stability of rice starch modified by acetylation

Valproic acid influences the expression of genes implicated with hyperglycaemia-induced complement and coagulation pathways

Because the liver plays a major role in metabolic homeostasis and secretion of clotting factors and inflammatory innate immune proteins, there is interest in understanding the mechanisms of hepatic cell activation under hyperglycaemia and whether this can be attenuated pharmacologically. We have previously shown that hyperglycaemia stimulates major changes in chromatin organization and metabolism in hepatocytes, and that the histone deacetylase inhibitor valproic acid (VPA) is able to reverse some of these metabolic changes. In this study, we have used RNA-sequencing (RNA-seq) to investigate how VPA influences gene expression in hepatocytes. Interesting, we observed that VPA attenuates hyperglycaemia-induced activation of complement and coagulation cascade genes. We also observe that many of the gene activation events coincide with changes to histone acetylation at the promoter of these genes indicating that epigenetic regulation is involved in VPA action11CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP304668/2014-12010/50015-6; 2012/03238-5; 2014/10198-5; 2015/10356-2NHMRC; International Joint Program. Professor Sam El-Osta is a National Health and Medical Research Council; Senior Research Fello

Antifungal activity of a novel chromene dimer

The activity on Aspergillus spp. growth and on ochratoxin A production of two novel chromene dimers (3) was evaluated. The results of the bioassays indicate that the chromene dimer 3a inhibited mycelia growth by approximately 50% (EC50) at 140.1 μmol L−1 for A. niger, 384.2 μmol L−1 for A. carbonarius, 69.1 μmol L−1 for A. alliaceus and 559.1 μmol L−1 for A. ochraceus. When applied at concentrations of 2 mmol L−1, 3a totally inhibited the growth of all Aspergillus spp. tested. Furthermore, ochratoxin A production by A. alliaceus was reduced by about 94% with a 200 μmol L−1 solution of this compound. A moderate inhibitory effect was observed for the analogous structure 3b on ochratoxin A production but not in mycelia growth. No inhibition was registered for compounds 2a and 2b, used as synthetic precursors of the dimeric species 3.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/ 11228/2002

Numerical study of the E⊗eE\otimes e Jahn-Teller polaron and bipolaron

The properties of the polaron and bipolaron are explored in the 1D Jahn-Teller model with dynamical quantum phonons. The ground-state properties of the polaron and bipolaron are computed using a recently developed variational method. Dynamical properties of the ground state of a polaron are investigated by calculating the optical conductivity $\sigma(\omega)$. Our numerical results suggest that the Jahn-Teller and Holstein polarons are similar. However, in the strong-coupling regime qualitative differences in $\sigma(\omega)$ between the two models are found and discussed. The influence of the electron-phonon coupling and the electrostatic repulsion on the bipolaron binding energy, bipolaron masses, and correlation functions is investigated.Comment: 9 pages including 11 figures. To appear in PR

Mucinose folicular na infância: um diagnóstico raro, mas significante

TCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências da Saúde. Medicina.Follicular mucinosis (MF) is a rare cutaneous disease with unclear etiology, it was firstly described by Pinkus et. al. in 1957, who named it mucinous alopecia, referring to a characteristic process of the MF, which leads to alopecia. As this process was not seen on all developments of the disease, in 1959 Jablonska et. al. proposed to name it Follicular mucinosis. Follicular mucinosis is uncommon in children. Using the online searching databases Scielo and PubMed, during the past 10 years, there were found only 16 pediatric case reports about the disease: 3 associated with mycosis fungoides (MFg), 1 about the acneiform presentation of the disease, 9 discussing the primary type, 1 did not specify the diagnosis in the report and 2 were about other presentations of the disease. The main concern of diagnosing a child with MF is whether it is associated with MFg, a cutaneous T-cell lymphoma, that although rare in children, when present is mostly associated with MF. The earlier the diagnosis of MFg is made, the better is the prognosis of the patient. Therefore, it is of great importance that a general practitioner pediatrician can diagnose a case of MF and identify whether it is associated with MFg or other systemic diseases.Mucinose folicular (MF) é uma doença cutânea rara e de etiologia incerta, mas que pode impactar drasticamente a qualidade de vida e o prognóstico dos pacientes. Dessa forma, o presente estudo busca divulgar, no meio científico, uma das possíveis apresentações clínicas da doença, além de reforçar a importância do seu diagnóstico e acompanhamento. A MF foi descrita pela primeira vez por Pinkus et. al. em 1957, que a nomeou Alopecia mucinosa referindo-se a um processo característico da MF, que leva a alopecia. Entretanto, como esse processo não ocorre em todos os casos da doença, em 1959, Jablonska et. al. propôs a alteração do nome para mucinose folicular. A MF é incomum em crianças: usando as bases de dados online da Scielo e do PubMed, foram encontrados apenas 16 relatos de casos pediátricos da doença durante os últimos 10 anos. Entre esses relatos, 3 eram associados à micose fungoide (MFg), 1 sobre a apresentação acneiforme (primária) da doença, 9 discutindo a forma primária clássica da doença, 1 não especificou o diagnóstico no relato e 2 são sobre outras apresentações da doença. A principal preocupação ao fazer um diagnóstico de mucinose folicular é investigar se ele é ou não associado à micose fungoide. A MFg é um linfoma cutâneo de células T, cujo diagnóstico precoce é essencial para um melhor prognóstico do paciente. Apesar de rara em crianças, quando a MFg está presente, é comumente associada a MF. Dessa forma, é de grande importância que um médico generalista consiga identificar um caso de mucinose folicular a fim de dar o encaminhamento necessário ao paciente, excluindo possíveis malignidades associadas