403 research outputs found
Noncommutative massive Thirring model in three-dimensional spacetime
We evaluate the noncommutative Chern-Simons action induced by fermions
interacting with an Abelian gauge field in a noncommutative massive Thirring
model in (2+1)-dimensional spacetime. This calculation is performed in the
Dirac and Majorana representations. We observe that in Majorana representation
when goes to zero we do not have induced Chern-Simons term in the
dimensional regularization scheme.Comment: Accepted to Phys. Rev. D; 9 pages, Revtex4, no figures, references
added, minor improvements, Eq.31 correcte
Landau Analog Levels for Dipoles in the Noncommutative Space and Phase Space
In the present contribution we investigate the Landau analog energy
quantization for neutral particles, that possesses a nonzero permanent magnetic
and electric dipole moments, in the presence of an homogeneous electric and
magnetic external fields in the context of the noncommutative quantum
mechanics. Also, we analyze the Landau--Aharonov--Casher and
Landau--He--McKellar--Wilkens quantization due to noncommutative quantum
dynamics of magnetic and electric dipoles in the presence of an external
electric and magnetic fields and the energy spectrum and the eigenfunctions are
obtained. Furthermore, we have analyzed Landau quantization analogs in the
noncommutative phase space, and we obtain also the energy spectrum and the
eigenfunctions in this context.Comment: 20 pages, references adde
Supergravity brane worlds and tachyon potentials
We study massless and massive graviton modes that bind on thick branes which
are supergravity domain walls solutions in -dimensional supergravity
theories where only the supergravity multiplet and the scalar supermultiplet
are turned on. The domain walls are bulk solutions provided by tachyon
potentials. Such domain walls are regarded as BPS branes of one lower dimension
that are formed due to tachyon potentials on a non-BPS D-brane.Comment: RevTex4, 6 pages; version to appear in Phys. Rev.
Influence of the scrotum bipartite on the reproductive parameters in goats
Avaliou-se a influência do grau de bipartição escrotal sobre os parâmetros reprodutivos em caprinos. Foram utilizados 30 animais, distribuídos em três grupos: Grupo I, animais que apresentavam escroto sem bipartição (n =10); Grupo II, animais com bipartição escrotal até 50% do comprimento dos testículos (n=10); e Grupo III, caprinos com bipartição escrotal acima de 50% do comprimento testicular (n=10). Os parâmetros avaliados foram peso corporal, perímetro escrotal, comprimento testicular, características físicas e morfológicas do sêmen, concentração plasmática de testosterona e libido dos animais, comparando caprinos com escroto bipartido e não bipartido. Os animais que apresentavam bipartição escrotal expressaram maior peso corporal e comprimento testicular, quando comparados com os animais do grupo sem escroto bipartido, sendo que estes apresentaram maior número de células espermáticas defeituosas. Conclui-se que a bipartição escrotal influencia positivamente alguns parâmetros biométricos bem como a qualidade do sêmen em caprinos.The influence of scrotum division on the reproductive parameters in goats was evaluated. Thirty animals were divided into three groups of 10 animals each as follows. Group I: animals with simple scrotum (n=10); Group II: animals with 50% of scrotum bipartite (n=10); and Group III: animals with more than 50% of scrotum bipartite (n=10). It was evaluated: body weight, scrotum perimeter and the testicular length, the seminal characteristic, plasmatic concentration of testosterone, and the libido of the animals with different degrees of scrotum division. Animals with divided scrotum had higher weight and testicular length when compared with animals from the first group that had a higher percentage of spermatic defects. It is possible to conclude that there was a positive influence of scrotal bipartition on the biometric parameters and the sperm quality in goats
Incidência E Mortalidade Por Aids Em Crianças E Adolescentes: Desafios Na Região Sul Do Brasil
The objective of this study is to describe the time trend of coefficients of incidence and mortality associated with AIDS in children and adolescents. An ecological time trend study was conducted among individuals under 14 living in the regional context of high incidence of AIDS – Porto Alegre and the State of Rio Grande do Sul – from 1996 to 2012. For this purpose, a segmented regression model was adjusted for age categories and place of residence. AIDS morbidity and mortality indicators in Porto Alegre are still higher than those registered in the State, the southern region and other areas of the country. In Porto Alegre, 59.1% of cases (371/628) occurred in children under four years of age, the incidence showed peaks in the period and the mortality dropped from 9 to 2 per 100,000. A significant decreasing in annual percentage change in mortality was observed especially in children under 1 year of age in Porto Alegre. This drop may be related to prevention and treatment of pregnant women. The challenge is to identify possible fragilities of the STD/AIDS Program and its vulnerable points in order to make specific interventions and investments with a greater impact potential. © 2016, Associacao Brasileira de Pos - Graduacao em Saude Coletiva. All rights reserved.21123889389
The role of boundary conditions on the dynamics of green coffee beans in a rotated dryer
[EN] Coffee drying and roasting are usually performed in rotated dryers; therefore, the study of particle dynamics in this equipment is of great relevance to improve their efficiency and hence the quality of the final product. Thus, this work aimed to investigate experimentally and numerically the dynamics of coffee beans in a rotary dryer. The Euler-Euler model was employed to reproduce the particle velocity profile in the rolling regime under different boundary conditions. The results shown that the lower specularity coefficient (0.01), which characterizes the smooth wall and free slip condition, reproduced the bed behavior that most resembled the experimental one. On the other hand, the other coefficients (0.1 and 1.0) showed an increasing deformation in the bed surface, different from the observed experimental behavior. It was also verified that, as the filling degree increases, the bed surface deformation becomes more pronounced.The authors would like to thank FAPEMIG, CNPq and CAPES for the financial resources assigned to carry out this work.Machado, M.; Resende, I.; Lima, R.; Brandão, R.; Pivello, M.; Nascimento, S.; Duarte, C.... (2018). The role of boundary conditions on the dynamics of green coffee beans in a rotated dryer. En IDS 2018. 21st International Drying Symposium Proceedings. Editorial Universitat Politècnica de València. 331-338. https://doi.org/10.4995/IDS2018.2018.7455OCS33133
Mycoplasma gallisepticum como fator de risco no peso de lotes de frangos de corte com condenação por aerossaculite na Inspeção Sanitária Federal
Marker assisted identification of tospovirus resistant tomato genotypes in segregating progenies
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