Nematic liquid crystal dynamics under applied electric fields

In this paper we investigate the dynamics of liquid crystal textures in a two-dimensional nematic under applied electric fields, using numerical simulations performed using a publicly available LIquid CRystal Algorithm (LICRA) developed by the authors. We consider both positive and negative dielectric anisotropies and two different possibilities for the orientation of the electric field (parallel and perpendicular to the two-dimensional lattice). We determine the effect of an applied electric field pulse on the evolution of the characteristic length scale and other properties of the liquid crystal texture network. In particular, we show that different types of defects are produced after the electric field is switched on, depending on the orientation of the electric field and the sign of the dielectric anisotropy.Comment: 7 pages, 12 figure

First study of the gluon-quark-antiquark static potential in SU(3) Lattice QCD

We study the long distance interaction for hybrid hadrons, with a static gluon, a quark and an antiquark with lattice QCD techniques. A Wilson loop adequate to the static hybrid three-body system is developed and, using a 24^3 x 48 periodic lattice with beta=6.2 and a ~ 0.075 fm, two different geometries for the gluon-quark segment and the gluon-antiquark segment are investigated. When these segments are perpendicular, the static potential is compatible with confinement realized with a pair of fundamental strings, one linking the gluon to the quark and another linking the same gluon to the antiquark. When the segments are parallel and superposed, the total string tension is larger and agrees with the Casimir Scaling measured by Bali. This can be interpreted with a type-II superconductor analogy for the confinement in QCD, with repulsion of the fundamental strings and with the string tension of the first topological excitation of the string (the adjoint string) larger than the double of the fundamental string tension.Comment: 4 pages RevTeX, 4 figure

Ecologia de Dermatobia hominis L. JR.1781 (Diptera:Cuterebridae) na região de São Carlos, estado de São Paulo, Brasil.

Lavras de Dermatobia hominis forma expostas, em condições naturais, para estudo da fase de vida livre

Temperature Measurement and Phonon Number Statistics of a Nanoelectromechanical Resonator

Measuring thermodynamic quantities can be easy or not, depending on the system that is being studied. For a macroscopic object, measuring temperatures can be as simple as measuring how much a column of mercury rises when in contact with the object. At the small scale of quantum electromechanical systems, such simple methods are not available and invariably detection processes disturb the system state. Here we propose a method for measuring the temperature on a suspended semiconductor membrane clamped at both ends. In this method, the membrane is mediating a capacitive coupling between two transmission line resonators (TLR). The first TLR has a strong dispersion, that is, its decaying rate is larger than its drive, and its role is to pump in a pulsed way the interaction between the membrane and the second TLR. By averaging the pulsed measurements of the quadrature of the second TLR we show how the temperature of the membrane can be determined. Moreover the statistical description of the state of the membrane, which is directly accessed in this approach is significantly improved by the addition of a Josephson Junction coupled to the second TLR.Comment: 9 pages, 5 figures. To appear in New Journal of Physic

Epidemiologia dos nematÓdeos gastrintestinais de bovinos leiteiros no município de São Carlos, Estado de São Paulo.

Durante o período de janeiro de 1981 ajaneiro de 1984 foram estudados os aspectos epide-miológicos dos nematódeosgastrintestinais de bovinos mestiços (Holandês x Zebu) no município de São Carlos, Estado de São Paulo. Das necropsias, foram recuperadas formas adultas e imaturas de nemató-deos, sendo constatadas as seguintes espácies:Cooperia punctata e C. pectinata;lfaemonchuscontor-sus e R. sim/lis; Trichostrongylus axei: Oesophagostornum radiatum; Diclyocaulus viviparus e Trichu-ris discolor. O crescimento do número de Jjaemonchug foi verificado na primavera, havendo em seguida um rápido declínio no início do verão. A maior incidência foi observada no final do verão,coinci-dindo com o final da estação chuvosa. As formas imaturas em hipobiose de Ifaemonchus foram obser-vadas em maio, julho e agosto. Os bioclimatográficos demonstraram a existência de condições desfa-voráveis para o desenvolvimento da forma de vida livre durante a estação seca, correspondendo aos meses de junho, julho, agosto e inicio de setembro

Fatores que afetam economicamente a produção de couro de bovinos.

Prejuízos materiais causadas a industria coureiro-calcadista, pela danificações nas peles de bovinos

Relação entre o peso da postura e o peso da fêmea ingurgitada de Boophilus microplus (Can). (Acarina: Ixodidae).

Foi observado o peso da postura e o peso da fêmea ingurgitada. As fêmeas foram colocadas em gaiolas individuais, sendo antes pesadas, o mesmo acontecendo com a oviposição final