The Teleparallel Lagrangian and Hamilton-Jacobi Formalism

We analyze the Teleparallel Equivalent of General Relativity (TEGR) from the point of view of Hamilton-Jacobi approach for singular systemsComment: 11 pages, no figures, to appear in GR

Cosmic strings in axionic-dilatonic gravity

We first consider local cosmic strings in dilaton-axion gravity and show that they are singular solutions. Then we take a supermassive Higgs limit and present expressions for the fields at far distances from the core by applying a Pecci-Quinn and a duality transformation to the dilatonic Melvin's magnetic universe.Comment: Latex file. 16 page

An analysis of cosmological perturbations in hydrodynamical and field representations

Density fluctuations of fluids with negative pressure exhibit decreasing time behaviour in the long wavelength limit, but are strongly unstable in the small wavelength limit when a hydrodynamical approach is used. On the other hand, the corresponding gravitational waves are well behaved. We verify that the instabilities present in density fluctuations are due essentially to the hydrodynamical representation; if we turn to a field representation that lead to the same background behaviour, the instabilities are no more present. In the long wavelength limit, both approachs give the same results. We show also that this inequivalence between background and perturbative level is a feature of negative pressure fluid. When the fluid has positive pressure, the hydrodynamical representation leads to the same behaviour as the field representation both at the background and perturbative levels.Comment: Latex file, 18 page

Was the GLE on May 17, 2012 linked with the M5.1-class flare the first in the 24th solar cycle?

On May 17, 2012 an M5.1-class flare exploded from the sun. An O-type coronal mass ejection (CME) was also associated with this flare. There was an instant increase in proton flux with peak at $\geq 100$ MeV, leading to S2 solar radiation storm level. In about 20 minutes after the X-ray emission, the solar particles reached the Earth.It was the source of the first (since December 2006) ground level enhancement (GLE) of the current solar cycle 24. The GLE was detected by neutron monitors (NM) and other ground based detectors. Here we present an observation by the Tupi muon telescopes (Niteroi, Brazil, $22^{0}.9 S$, $43^{0}.2 W$, 3 m above sea level) of the enhancement of muons at ground level associated with this M5.1-class solar flare. The Tupi telescopes registered a muon excess over background $\sim 20\%$ in the 5-min binning time profile. The Tupi signal is studied in correlation with data obtained by space-borne detectors (GOES, ACE), ground based neutron monitors (Oulu) and air shower detectors (the IceTop surface component of the IceCube neutrino observatory). We also report the observation of the muon signal possibly associated with the CME/sheath striking the Earth magnetosphere on May 20, 2012. We show that the observed temporal correlation of the muon excess observed by the Tupi muon telescopes with solar transient events suggests a real physical connection between them. Our observation indicates that combination of two factors, the low energy threshold of the Tupi muon telescopes and the location of the Tupi experiment in the South Atlantic Anomaly region, can be favorable in the study and detection of the solar transient events. Our experiment provides new data complementary to other techniques (space and ground based) in the study of solar physics.Comment: 9 pages, 10 figure

Propagating Torsion in 3D-Gravity and Dynamical Mass Generation

In this paper, fermions are minimally coupled to 3D-gravity where a dynamical torsion is introduced. A Kalb-Ramond field is non-minimally coupled to these fermions in a gauge-invariant way. We show that a 1-loop mass generation mechanism takes place for both the 2-form gauge field and the torsion. As for the fermions, no mass is dynamically generated: at 1-loop, there is only a mass shift proportional to the Yukawa coupling whenever the fermions have a non-vanishing tree-level mass.Comment: 13 pages, latex file, no figures, some corrections adde

Consumo voluntário das silagens de capim elefante com diferentes níveis de subprodutos da indústria do suco de caju.

O trabalho foi realizado com objetivo de avaliar o consumo voluntário das silagens de capim elefante (Pennisetum purpureum Schum) confeccionadas com adição de 0, 12, 24, 36 e 48% de bagaço de caju (subproduto da agroindústria de suco caju) em relação à matéria natural. O delineamento utilizado foi o inteiramente casualizado com quatro repetições. O consumo das silagens ( g/animal/dia e g/UTM) foram efetuados utilizando carneiros machos sem raça definida (SRD). Os animais foram mantidos em gaiolas de metabolismo individuais, durante 21 dias, sendo, 14 dias para adaptação dos animais e 7 dias para determinação do consumo voluntário. Nesse período foram coletadas amostras de silagens e sobras para determinação do consumo de matéria seca (CMS), proteína bruta (CPB), fibra em detergente neutro (CFDN), fibra em detergente ácido (CFDA) e carboidratos totais (CCT). A adição de bagaço de caju (BC) promoveu aumento no consumo de CMS, CPB, CFDN, CFDA e CCT, evidenciados nos tratamentos com 36 e 48%. Pelos resultados obtidos conclui-se que o bagaço de caju melhora o valor nutritivo, embora os valores tenham sido inferiores, quando comparados com silagens convencionais

Viabilidade econômica da terminação de cordeiros em pastagem cultivada.

O presente trabalho, realizado na Embrapa Caprinos, em Sobral - CE, avaliou a terminação de cordeiros em pastagem de capim gramão e capim tanzânia, sob duas taxas de lotação. O período de terminação foi de 83 dias. O lucro obtido com a terminação de cordeiros em pastagem de gramão (Cynodon dactylon) e venda dos animais em pé foi de R$1,58/cordeiro e R$ 3,77/cordeiro, para taxas de lotação de 40 e 60 animais/h a, respectivamente. Nas áreas de tanzânia (Panicum maximum), o lucro obtido foi de R$4,31/cordeiro e R$ 2,64/cordeiro, para taxas de lotação de 40 e 60 animais/ha, respectivamente. Entretanto, cada ha permitiu a terminação de 4,4 lotes por ano. Com isso, o lucro anual da terminação no gramão foi de R$277,30/ha e R$ 995,66/ha nas taxas de lotação de 40 e 60 animais/ha, respectivamente. A terminação à pasto no tanzânia proporcionou um lucro anual de R$758,64/ha e R$ 697,65/ha nas taxas de lotação de 40 e 60 animais/ha, respectivamente. A venda dos animais abatidos proporcionou um lucro anual de R$94,79/ha e de R$ 233,23/ha para taxas de lotação de 40 e 60 animais/ha, respectivamente, no gramão. Já em pastagem de tanzânia, a venda dos animais abatidos proporcionou um lucro anual de R$198,79/ha e R$ 891 ,95/ha para as taxas de lotação de 40 e 60 anímais/ha, respectivamente. Economic viability of lamb finishing on cultivated pasture. Abstract: The present work carried out at Embrapa Caprinos, Sobral-CE, evaluated lamb finishing on cultivated pastureof coast-cross (Cynodon dactylon) and tanzania grass (Panicum maximum cv. tanzania) with two stocking rates. Finishing took 83 days. The profit obtained with lamb finishing on coast-cross grass was of R$1.58/lamb and R$ 3.77/lamb for stocking rates of 40 and 60 lambs/ha, respectively. In the areas of tanzania grass the achieved profit was of R$4.31/lamb and R$ 2.64/lamb for stocking rates of 40 and 60 lambs/ha, respectively. However, each ha allowed the termination of 4.4 flocks per year. With this, the annual profit of the termination on pasture of coast-cross was of R$277.30/ha and R$ 995.66/ha for stocking rates of 40 and 60 lambs/ha, respectively. The termination in pasture of tanzania grass enabled an annual profit of R$758.64/ha and R$ 697.65/ha for stocking rates of 40 and 60 lambs/ha, respectively. When commercializing carcass, the yearly profit obtainable was of R$94.79/ha and R$ 233.23/ha for stocking rates of 40 and 60 lambs/ha, respectively, on coast-cross. On tanzania grass, the yearly obtainable profit was of R$198.79/ha and R$ 891.95/ha for stocking rates of 40 and 60 lambs/ha, respectively. Lamb finishing on pasture was economically vi able