On the Space Time of a Galaxy

We present an exact solution of the averaged Einstein's field equations in the presence of two real scalar fields and a component of dust with spherical symmetry. We suggest that the space-time found provides the characteristics required by a galactic model that could explain the supermassive central object and the dark matter halo at once, since one of the fields constitutes a central oscillaton surrounded by the dust and the other scalar field distributes far from the coordinate center and can be interpreted as a halo. We show the behavior of the rotation curves all along the background. Thus, the solution could be a first approximation of a ``long exposition photograph'' of a galaxy.Comment: 8 pages REVTeX, 11 eps figure

Two Distinct, Geographically Overlapping Lineages of the Corallimorpharian Ricordea Florida (Cnidaria: Hexacorallia: Ricordeidae)

We examined the genetic variation of the corallimorpharian Ricordea florida; it is distributed throughout the Caribbean region and is heavily harvested for the marine aquarium trade. Eighty-four distinct individuals of R. florida were sequenced from four geographically distant Caribbean locations (Curaçao, Florida, Guadeloupe, and Puerto Rico). Analysis of the ribosomal nuclear region (ITS1, 5.8S, ITS2) uncovered two geographically partially overlapping genetic lineages in R. florida, probably representing two cryptic species. Lineage 1 was found in Florida and Puerto Rico, and Lineage 2 was found in Florida, Puerto Rico, Guadeloupe, and Curaçao. Because of the multi-allelic nature of the ITS region, four individuals from Lineage 1 and six from Lineage 2 were cloned to evaluate the levels of hidden intra-individual variability. Pairwise genetic comparisons indicated that the levels of intra-individual and intra-lineage variability (\u3c1%) were approximately an order of magnitude lower than the divergence (~9%) observed between the two lineages. The fishery regulations of the aquarium trade regard R. florida as one species. More refined regulations should take into account the presence of two genetic lineages, and they should be managed separately in order to preserve the long-term evolutionary potential of this corallimorpharian. The discovery of two distinct lineages in R. florida illustrates the importance of evaluating genetic variability in harvested species prior to the implementation of management policies

Bose-Einstein condensate dark matter phase transition from finite temperature symmetry breaking of Klein-Gordon fields

In this paper the thermal evolution of scalar field dark matter particles at finite cosmological temperatures is studied. Starting with a real scalar field in a thermal bath and using the one loop quantum corrections potential, we rewrite Klein-Gordon's (KG) equation in its hydrodynamical representation and study the phase transition of this scalar field due to a Z_2 symmetry breaking of its potential. A very general version of a nonlinear Schr\"odinger equation is obtained. When introducing Madelung's representation, the continuity and momentum equations for a non-ideal SFDM fluid are formulated, and the cosmological scenario with the SFDM described in analogy to an imperfect fluid is then considered where dissipative contributions are obtained in a natural way.Additional terms appear compared to those obtained in the classical version commonly used to describe the \LambdaCDM model, i.e., the ideal fluid. The equations and parameters that characterize the physical properties of the system such as its energy, momentum and viscous flow are related to the temperature of the system, scale factor, Hubble's expansion parameter and the matter energy density. Finally, some details on how galaxy halos and smaller structures might be able to form by condensation of this SF are given.Comment: Substantial changes have been made to the paper, following the referees recommendations. 16 pages. Published in Classical and Quantum Gravit

Quintessence and Scalar Dark Matter in the Universe

Continuing with previous works, we present a cosmological model in which dark matter and dark energy are modeled by scalar fields $\Phi$ and $\Psi$, respectively, endowed with the scalar potentials $V(\Phi)=V_{o}[ \cosh {(\lambda \sqrt{\kappa_{o}}\Phi)}-1]$ and $\tilde{V}(\Psi)=\tilde{V_{o}}[ \sinh {(\alpha \sqrt{\kappa_{o}}\Psi)}] ^{\beta}$. This model contains 95% of scalar field. We obtain that the scalar dark matter mass is $m_{\Phi}\sim 10^{-26}eV.$ The solution obtained allows us to recover the success of the standard CDM. The implications on the formation of structure are reviewed. We obtain that the minimal cutoff radio for this model is $r_{c}\sim 1.2 kpc.$Comment: 4 pages REVTeX, 3 eps color figures. Minor changes and references updated. To appear in Classical and Quantum Gravity as a Letter to the Editor. More information at http://www.fis.cinvestav.mx/~siddh/PHI

Mass Production and Morphology of Marandu Brachiaria Under Different Nitrogen Rates in the Brazilian Savannah

Nitrogen is the nutrient that most contributes to increase forage productivity and quality. The objective was to evaluate Marandu brachiaria submitted to nitrogen doses in the Brazilian savannah through the total and green mass production, leaf:stem and brachiaria:weed ratio. Plots were established in a randomized block design, with four replications and four N doses 0, 50, 100 and 150 kg N/ha). After the uniformization cut, the data collect cycles occurred when the canopy reached 30 cm average height. Samples were taken until 15 cm from the ground in an area of 0.25 m2. Fractions were separated according botanical (brachiaria and weeds) and morphological (leaf, stem, dead material and inflorescence) components. The highest value of dry matter production and green mass production occurred at 96 and 72 kg N/ha dose (2,669 kg and 1,946 DM/ha). Above and below this value the mass production decreased . The highest relation green mass:dead material ratio was 4.00 at 150 kg N/ha dose. Marandu was able to control the weeds, and the best performance (4.67) was observed at 78 kg N/ha dose. Forage accumulation rate is the mass production/day and the highest accumulation rate occurred at 50 kg N/ha dose. Marandu had higher leaf:stem ratio with nitrogen dose 107 kg N/ha but above 50 kg/N the mass accumulation rate decrease which means that the fertilization cost is not favorable over up this dose, especially above dose 72 kg N/kg when there green mass production decrease

Complications of endomyocardial biopsy in heart transplant patients: a retrospective study of 2117 consecutive procedures

BACKGROUND: Endomyocardial biopsy (EMB) remains the gold standard for the diagnosis of graft rejection after heart transplantation (HT). Our purpose was to evaluate the rate of complications of this invasive procedure. METHODS: This was a retrospective study of 175 patients, who were transplanted between November 2003 and October 2010 and survived more than 1 month after surgery. We evaluated the number of inconclusive EMB and described the incidence, nature, and subsequent management of several complications associated with this procedure. RESULTS: Over a period of approximately 7 years, we performed 2217 EMB yielding 4972 specimens, namely, an average of 2.3 fragments per procedure. The majority of EMBs (95.3%) were performed by the femoral approach. Only 12 EMB (0.57%) were inconclusive. The overall complication rate was 0.71%. During puncture, one patient experienced a vasovagal reaction and another one, a femoral artery false aneurysm. During the biopsy, there was one case of cardiac perforation with tamponade, two cases of supraventricular tachycardia, and three atrioventricular conduction abnormalities. In 19 patients, histological analysis revealed chordal tissue, but only two patients developed mild tricuspid regurgitation. We observed five cases of coronary artery fistulae. The clinical outcomes were favorable in all cases. CONCLUSION: EMB proved to be a suitable, safe method to monitor rejection after HT

Regeneração de espécies silvestres brasileiras de arroz através do cultivo de embrião.

O objetivo deste trabalho foi regenerar os acessos das espécies silvestres de arroz brasileiras através do cultivo de embriões

Quantum mechanical counterpart of nonlinear optics

Raman-type laser excitation of a trapped atom allows one to realize the quantum mechanical counterpart of phenomena of nonlinear optics, such as Kerr-type nonlinearities, parametric amplification, and multi-mode mixing. Additionally, huge nonlinearities emerge from the interference of the atomic wave function with the laser waves. They lead to a partitioning of the phase space accompanied by a significantly different action of the time evolution in neighboring phase-space zones. For example, a nonlinearly modified coherent "displacement" of the motional quantum state may induce strong amplitude squeezing and quantum interferences.Comment: 6 pages, 4 figures, to be published in Phys. Rev. A 55 (June