Fermionic vacuum polarization induced by a non-Abelian vortex

In this paper, we analyze the fermionic condensate (FC) and the vacuum expectation value (VEV) of the energy-momentum tensor associated with an isospin-$1/2$ charged massive fermionic field induced by the presence of a $SU(2)$ vortex, taking into account the effect of the conical geometry produced by this object. We consider the vortex as an idealized topological defect, i.e., very thin, straight and carrying a magnetic flux running along its core. Besides the direct coupling of the fermionic field with the iso-vector gauge field, we also admit the coupling with the scalar sector of the non-Abelian vortex system, expressed as a vector in the three-dimensional isospace. Due to this interaction, the FC is expressed as the sum of two contributions associated with the two different effective masses for the $\pm 1/2$ fermionic components of the isospin operator, $\tau^3/2$. The VEV of the energy-tensor also presents a similar structure. The vacuum energy density is equal to the radial and axial stresses. As to the azimuthal one, it is expressed in terms of the radial derivative of energy-density. Regarding to the magnetic flux, both, the FC and the VEV of the energy-momentum tensor, can be positive or negative. Another interesting consequence of the interaction with the bosonic sector, the FC and VEV of the energy-momentum tensor, present different intensity for different values of the ratio between the scalar coupling constant and the mass of the fermionic field. This is a new feature that the system presents.Comment: 24 pages, 4 figures. Version accepted for publication in IJMP

Bosonic Casimir effect in an aether-like Lorentz-violating scenario with higher order derivatives

In this paper we investigate the bosonic Casimir effect in a Lorentz-violating symmetry scenario. The theoretical model adopted consists of a real massive scalar quantum field confined in a region between two large parallel plates, having its dynamics governed by a modified Klein-Gordon equation that presents a Lorentz symmetry breaking term. In this context we admit that the quantum field obeys specific boundary conditions on the plates. The Lorentz-violating symmetry is implemented by the presence of an arbitrary constant space-like vector in a CPT-even aether-like approach, considering a direct coupling between this vector with the derivative of the field in higher order. The modification on the Klein-Gordon equation produces important corrections on the Casimir energy and pressure. Thus, we show that these corrections strongly depend on the order of the higher derivative term and the specific direction of the constant vector, as well as the boundary conditions considered.Comment: 21 pages, 5 figure

Produção de matéria seca de meloeiro adubado com compostos orgânicos provenientes de diferentes resíduos.

A compostagem tem sido utilizada em cultivos perenes em substituição ao esterco puro e como alternativa para reciclagem de resíduos provenientes da atividade agrícola. Existem diversos materiais que podem ser transformados em composto e osteriormente enriquecidos para o fornecimento de nutrientes essenciais em cultivo orgânico. O objetivo do presente trabalho foi avaliar a produção de matéria seca de meloeiro adubado com compostos orgânicos provenientes de diferentes resíduos. O compostos que produziram maior matéria seca do melão foram os que tinham como base o bagaço de coco. As massas da matéria seca de folha e de ramos foram muito influenciadas pelos tipos de compostos utilizados, enquanto o de flores + gavinhas praticamente não foi afetado.Edição dos resumos expandidos do 45. Congresso Brasileiro de Olericultura; 15. Congresso Brasileiro de Floricultura e Plantas ornamentais; 2. Congresso Brasileiro de Cultura de Tecidos de Plantas, Fortaleza, ago. 2005. 1 CD-ROM

Considerations about Ucides cordatus cordatus fishing in the Parnaíba River Delta Region, Brazil.

The uçá-crab, Ucides cordatus cordatus, is distinguished as one of the most explored fisherie resources in Brazil. The Parnaíba River Delta Region, located between the states of Piauí and Maranhão, has the greatest concentration of crab catcher in the entire country. Evidence of over-exploitation highlights need of better control over crab fishing activities in this region. The present work has as objective to determine the uçá-crab capture per effort unit (CPUE) in the Parnaíba River Delta, in order to supply subsidies for the fisherie management of this resorce. Fishery data collection was carried out during 1999 throughout 2002, between the latitudes 2º40' and 2º45' and the longitudes 41º51' and 42º05'. The CPUE was determined as the number of crabs captured by catcher per day. The total monthly capture was esteemed considering the average between all years and the number of 4.500 operating catchers in the region. The average CPUE values varied between 14.6 and 22.6 crabs per catcher per day. The total monthly capture varied between 1.314.000 and 2.034.000 crabs, in the months of minimum and maximum CPUE, respectively. In the period of one year, about 21 millium crabs are captured. The obtained results, added to the over-fishing indications, bring to the conclusion that the collapse of crab fishing is a question of time in the region of the Parnaíba River Delta if the appropriate measures for adequate managing of the resource.Proceedings of the 8thInternational Coastal Symposium - ICS 2004

Considerations about Ucides cordatus cordatus fishing in the Parnaíba River Delta Region, Brazil.

The uçá-crab, Ucides cordatus cordatus, is distinguished as one of the most explored fisherie resources in Brazil. The Parnaíba River Delta Region, located between the states of Piauí and Maranhão, has the greatest concentration of crab catcher in the entire country. Evidence of over-exploitation highlights need of better control over crab fishing activities in this region. The present work has as objective to determine the uçá-crab capture per effort unit (CPUE) in the Parnaíba River Delta, in order to supply subsidies for the fisherie management of this resorce. Fishery data collection was carried out during 1999 throughout 2002, between the latitudes 2º40' and 2º45' and the longitudes 41º51' and 42º05'. The CPUE was determined as the number of crabs captured by catcher per day. The total monthly capture was esteemed considering the average between all years and the number of 4.500 operating catchers in the region. The average CPUE values varied between 14.6 and 22.6 crabs per catcher per day. The total monthly capture varied between 1.314.000 and 2.034.000 crabs, in the months of minimum and maximum CPUE, respectively. In the period of one year, about 21 millium crabs are captured. The obtained results, added to the over-fishing indications, bring to the conclusion that the collapse of crab fishing is a question of time in the region of the Parnaíba River Delta if the appropriate measures for adequate managing of the resource

Oxidative stress involving changes in Nrf2 and ER stress in early stages of Alzheimer's disease

AbstractOxidative stress and endoplasmic reticulum (ER) stress have been associated with Alzheimer's disease (AD) progression. In this study we analyzed whether oxidative stress involving changes in Nrf2 and ER stress may constitute early events in AD pathogenesis by using human peripheral blood cells and an AD transgenic mouse model at different disease stages. Increased oxidative stress and increased phosphorylated Nrf2 (p(Ser40)Nrf2) were observed in human peripheral blood mononuclear cells (PBMCs) isolated from individuals with mild cognitive impairment (MCI). Moreover, we observed impaired ER Ca2+ homeostasis and increased ER stress markers in PBMCs from MCI individuals and mild AD patients. Evidence of early oxidative stress defense mechanisms in AD was substantiated by increased p(Ser40)Nrf2 in 3month-old 3xTg-AD male mice PBMCs, and also with increased nuclear Nrf2 levels in brain cortex. However, SOD1 protein levels were decreased in human MCI PBMCs and in 3xTg-AD mice brain cortex; the latter further correlated with reduced SOD1 mRNA levels. Increased ER stress was also detected in the brain cortex of young female and old male 3xTg-AD mice. We demonstrate oxidative stress and early Nrf2 activation in AD human and mouse models, which fails to regulate some of its targets, leading to repressed expression of antioxidant defenses (e.g., SOD-1), and extending to ER stress. Results suggest markers of prodromal AD linked to oxidative stress associated with Nrf2 activation and ER stress that may be followed in human peripheral blood mononuclear cells

Molecular characterization of Burkholderia mallei strains isolated from horses in Brazil (2014-2017).

Glanders is an infectious zoonosis caused by Burkholderia (B.) mallei that mainly affects equids. The objective of this work was to provide additional knowledge on the diversity of the strains circulating in Brazil. Six Burkholderia mallei isolates obtained during necropsies of glanderous horses between 2014 and 2017 in two different states (Pernambuco and Alagoas) were analyzed by polymerase chain reaction?high-resolution melting (PCRHRM). While four strains (9902 RSC, BM_campo 1, BM_campo 3 and UFAL2) clustered in the L3B2 branch, which already includes the Brazilian 16-2438_BM#8 strain, two strains (BM_campo 2.1 and BM_campo 2.2) clustered within the L3B3sB3 branch, which mostly includes older isolates, from Europe and the Middle East. Whole genome sequencing of two of these strains (UFAL2 and BM_campo 2.1), belonging to different branches, confirmed the HRM typing results and refined the links between the strains, including the description of the L3B3Sb3Gp1SbGp1 genotype, never reported so far for contemporary strains. These results suggest different glanders introduction events in Brazil, including a potential link with strains of European origin, related to colonization or trade