Vector meson quasinormal modes in a finite-temperature AdS/QCD model

We study the spectrum of vector mesons in a finite temperature plasma. The plasma is holographically described by a black hole AdS/QCD model. We compute the boundary retarded Green's function using AdS/CFT prescriptions. The corresponding thermal spectral functions show quasiparticle peaks at low temperatures. Then we calculate the quasinormal modes of vector mesons in the soft-wall black hole geometry and analyse their temperature and momentum dependences.Comment: 27 pages, 9 figure

Minimum cbits for remote preperation and measurement of a qubit

We show that a qubit chosen from equatorial or polar great circles on a Bloch spehere can be remotely prepared with one cbit from Alice to Bob if they share one ebit of entanglement. Also we show that any single particle measurement on an arbitrary qubit can be remotely simulated with one ebit of shared entanglement and communication of one cbit.Comment: Latex, 7 pages, minor changes, references adde

Análise da variabilidade espaço-temporal da precipitação pluviométrica no estado do rio grande do sul.

O objetivo deste estudo foi analisar a variabilidade espaço-temporal da precipitação pluviométrica no estado do Rio Grande do Sul entre 1987 e 2006, por meio da definição de zonas pluviometricamente homogêneas. Foram utilizados dados diários de precipitação pluviométrica de 79 estações adquiridos junto ao site da Agência Nacional de Águas (ANA). A série foi dividida em dois períodos de 10 anos (1987 a 1996 e 1997 a 2006). A clusterização (agrupamento) foi a tarefa empregada e o programa computacional utilizado para obtenção das zonas homogêneas foi o Weka®, sendo o k-means o algoritmo escolhido. A partir da análise dos dados mensais foram definidas quatro regiões homogêneas, nos dois períodos analisados. Comparando-se os dois períodos, verificou-se um deslocamento espacial dos agrupamentos, assim como um aumento da precipitação no período de 1997 a 2006.SBIAgro 2009

Scattering and Bound State Green's Functions on a Plane via so(2,1) Lie Algebra

We calculate the Green's functions for the particle-vortex system, for two anyons on a plane with and without a harmonic regulator and in a uniform magnetic field. These Green's functions which describe scattering or bound states (depending on the specific potential in each case) are obtained exactly using an algebraic method related to the SO(2,1) Lie group. From these Green's functions we obtain the corresponding wave functions and for the bound states we also find the energy spectra.Comment: 21 Latex pages. Typos corrected. Results unchanged. Version to appear in JM

Recent results of a seismically isolated optical table prototype designed for advanced LIGO

The Horizontal Access Module Seismic Attenuation System (HAM-SAS) is a mechanical device expressly designed to isolate a multipurpose optical table and fit in the tight space of the LIGO HAM Ultra-High-Vacuum chamber. Seismic attenuation in the detectors' sensitivity frequency band is achieved with state of the art passive mechanical attenuators. These devices should provide an attenuation factor of about 70dB above 10Hz at the suspension point of the Advanced LIGO triple pendulum suspension. Automatic control techniques are used to position the optical table and damp rigid body modes. Here, we report the main results obtained from the full scale prototype installed at the MIT LIGO Advanced System Test Interferometer (LASTI) facility. Seismic attenuation performance, control strategies, improvements and limitations are also discussed

The mysterious eruption of V838 Mon

V838 Mon is marking one of the most mysterious stellar outbursts on record. The spectral energy distribution of the progenitor resembles an under-luminous F main sequence star (at V=15.6 mag), that erupted into a cool supergiant following a complex and multi-maxima lightcurve (peaking at V=6.7 mag). The outburst spectrum show BaII, LiI and lines of several s-elements, with wide P-Cyg profiles and a moderate and retracing emission in the Balmer lines. A light-echo discovered expanding around the object helped to constrain the distance (d=790+/-30 pc), providing M_V=+4.45 in quiescence and M_V=-4.35 at optical maximum (somewhat dependent on the still uncertain E(B-V)=0.5 reddening). The general outburst trend is toward lower temperatures and larger luminosities, and continuing so at the time of writing. The object properties conflict with a classification within already existing categories: the progenitor was not on a post-AGB track and thus the similarities with the born-again AGB stars FG Sge, V605 Aql and Sakurai's object are limited to the cool giant spectrum at maximum; the cool spectrum, the moderate wind velocity (500 km/sec and progressively reducing) and the monotonic decreasing of the low ionization condition argues against a classical nova scenario. The closest similarity is with a star that erupted into an M-type supergiant discovered in M31 by Rich et al. (1989), that became however much brighter by peaking at M_V=-9.95, and with V4332 Sgr that too erupted into an M-type giant (Martini et al. 1999) and that attained a lower luminosity, closer to that of V838 Mon. M31-RedVar, V4332 Sgr and V838 Mon could be manifestations of the same and new class of astronomical objects.Comment: A&A, in pres

Operações de álgebra de mapas em sistema de informações geográficas para estimativa da aptidão agrícola das terras.

The land suitability evaluation is used to establish land zonings for agriculture. Geographic information systems (GIS) are useful for integrating different attributes necessaries to define apt and not apt lands. In tropical environment, soil fertility and water availability for cultures are very important in agricultural systems management. The present study had as main objective to describe procedures to define land suitability using GIS, soils maps, and data soils profiles data, emphasizing procedures to define fertility deficiency and water deficiency. Numerical terrain models (NTM) had been construct for cation exchange capacity, basis saturation, clay content and silt+clay content using kriging (geostatistical interpolator), and for aluminum saturation using the inverse-square-distance. Boolean operations for handling geographic fields (thematic maps and NTM) to produce information plans are describe

Fidelity of Quantum Teleportation through Noisy Channels

We investigate quantum teleportation through noisy quantum channels by solving analytically and numerically a master equation in the Lindblad form. We calculate the fidelity as a function of decoherence rates and angles of a state to be teleported. It is found that the average fidelity and the range of states to be accurately teleported depend on types of noise acting on quantum channels. If the quantum channels is subject to isotropic noise, the average fidelity decays to 1/2, which is smaller than the best possible value 2/3 obtained only by the classical communication. On the other hand, if the noisy quantum channel is modeled by a single Lindblad operator, the average fidelity is always greater than 2/3.Comment: 6 pages, 5 figures, accepted for publication in Phys. Rev.

Clinical outcome of latissimus dorsi tendon transfer and partial cuff repair in irreparable postero-superior rotator cuff tear

Background and purpose Irreparable rotator cuff tears are a common cause of pain in adult population, requiring in many cases a surgical treatment. Possible alternatives are debridement, partial repair, muscle transfers and joint replacement. We evaluated two groups of patients with irreparable rotator cuff tear treated surgically: one group received an arthroscopic-assisted latissimus dorsi tendon transfer (LDTT), and the other an arthroscopic rotator cuff partial repair. Aim of our study was to compare clinical results and quality of life in two groups of patients with massive irreparable rotator cuff tear: one receiving an arthroscopic LDTT and the other receiving an arthroscopic rotator cuff partial repair. Methods Forty patients were assigned to two groups: 20 patients to group TT treated with LDTT and 20 patients to group PR treated with a partial repair. The average follow-up duration was 2.8 years (1\u20135, SD 3). Pre- and postoperative modified UCLA shoulder score, ROM, measurement of the strength and the rotator cuff quality of life (RC-QOL) were used to asses the outcome. Results LDTT showed significative improvements when compared to partial repair in UCLA score results, strength and RC-QOL questionnaire. No differences were found between the groups in pain relief. Conclusion Both techniques are effective in reducing patients\u2019 symptoms. We believe that in younger, high-demanding patients with no or mild osteoarthritis, the LDTT represents a valid treatment option with better modified UCLA score improvement and strength at our follow-up