Initial-condition problem for a chiral Gross-Neveu system

A time-dependent projection technique is used to treat the initial-value problem for self-interacting fermionic fields. On the basis of the general dynamics of the fields, we derive formal equations of kinetic-type for the set of one-body dynamical variables. A nonperturbative mean-field expansion can be written for these equations. We treat this expansion in lowest order, which corresponds to the Gaussian mean-field approximation, for a uniform system described by the chiral Gross-Neveu Hamiltonian. Standard stationary features of the model, such as dynamical mass generation due to chiral symmetry breaking and a phenomenon analogous to dimensional transmutation, are reobtained in this context. The mean-field time evolution of nonequilibrium initial states is discussed.

Sodium chloride added to transport water and physiological responses of Matrinxã Brycon amazonicus (Teleost: Characidae)

A adição de sal à água tem sido utilizada para a mitigação de estresse e aumento da taxa de sobrevivência em peixes. O presente estudo avaliou o efeito do cloreto de sódio (0,0; 1,0; 3,0 e 6.0 g/l) nas concentrações de cortisol plasmático, glicemia, triglicerídios, proteínas total plasmática, hematócrito, hemoglobina, número de eritrócitos, glicogênio e lipídio hepáticos, e lipídio muscular em matrinxã Brycon amazonicum adultos após quatro horas de transporte e durante período de recuperação de 96 h. Amostras foram coletadas antes e depois do transporte, bem como 24 e 96 h após a chegada. O nível de cortisol plasmático estava mais elevado logo após o transporte quando comparado à condição inicial (pré-transporte), exceto para os peixes transportados com sal nas concentrações 3,0 e 6,0 g/l. Comportamento semelhante foi observado para a glicemia, porém os peixes dos tratamentos 0,0, 1,0 e 3,0 g/l necessitaram de período superior a 24 h para recuperar a condição inicial. Foram registrados níveis mais baixos de glicogênio hepático em peixes do tratamento controle (0,0 g/l). Os parâmetros hemoglobina, número de eritrócitos, proteína plasmática total e lipídio hepático não apresentaram alterações durante o período experimental. Os valores de hematócrito diminuíram logo após o transporte em todos os tratamentos, retornando aos níveis iniciais após 24 h. Todos os tratamentos apresentaram redução nos níveis de lipídio muscular e triglicerídios durante o período de recuperação. Os resultados sugerem que a adição de 6,0 g/l de sal na água de transporte reduz as alterações fisiológicas de estresse e que é necessário período de 96 h após o transporte para a recuperação da condição inicial de matrinxãs transportados sem a adição de sal.

Physiological responses of piau (Leporinus friderici, Bloch 1794) to transportation

This study evaluated stress indicators of juvenile piau (Leporinus friderici) during and after a 4-hour transportation in order to establish an appropriate transportation protocol for this type of fish. Fish were transported in plastic bags (133.1 g/L) and sampled before loading, during 1, 2, 3 and 4 h and after transportation (2, 6, 12 and 24 h). Blood samples were analyzed for cortisol and glucose levels, hematocrit, hemoglobin level, number and mean corpuscular volume of erythrocytes. Water pH, dissolved oxygen, temperature and ammonia were monitored before, during and after transportation. No mortality was observed through the experiment. Ammonia levels increased throughout transportation, but the low pH values kept NH3 in safe levels for fish. Cortisol levels increased within 4 h of transportation, and returned to control condition 2 h after arrival. Plasma glucose increased within one hour of transportation, reaching peak value within 4 h and returning to initial condition 2 h after arrival. Erythrocyte number and hemoglobin levels showed the lowest levels 2 h after arrival, and mean corpuscular volume increased during transportation, decreasing at 12 and 24 h after arrival. Transporting piau is stressful, but fish recover the initial condition in short time, showing tolerance to the changes in the water quality parameters.

HOPF BIFURCATION FROM LINES of EQUILIBRIA WITHOUT PARAMETERS IN MEMRISTOR OSCILLATORS

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

3D relativistic hydrodynamic computations using lattice-QCD-inspired equations of state

In this communication, we report results of three-dimensional hydrodynamic computations, by using equations of state with a critical end Point as suggested by the lattice QCD. Some of the results are an increase of the multiplicity in the mid-rapidity region and a larger elliptic-flow parameter nu(2). We discuss also the effcts of the initial-condition fluctuations and the continuous emission.

Land reform in NE Brazil: a stochastic frontier production efficiency evaluation

O objetivo desse artigo é caracterizar as fontes da ineficiência técnica e alocativa em um conjunto de 308 beneficiários de um programa de reforma agrária de mercado, chamado Cédula da Terra;, distribuídos em cinco estados do Nordeste brasileiro. Estudos conduzidos por Buainain et al. (2002) mostraram existem poucas diferenças entre as características de beneficiários deste programa e dos programas tradicionais de reforma agrária por expropriação e que portanto, os resultados obtidos por este trabalho permitem visualizar as dificuldades enfrentadas pelos assentamentos no Brasil. Para medir eficiência, estimou-se uma função de produção potencial segundo a metodologia de Battese e Coelli (1995) e a partir disto, procurou-se explicar as razões da ineficiência (relativa) encontrada. Os resultados apontam para a existência de ineficiência técnica e alocativa que é identificada principalmente nas situações em que a presença de produção para consumo é elevada. Tratase de um resultado que revela a pouca maturidade da maioria dos lotes dos assentados do PCT e a dificuldade de superar as limitações impostas pela condição inicial de formação dos assentamentos de reforma agrária, principalmente na região nordeste do Brasil.

Distant stable direct orbits around the Moon

In the present work we explore regions of distant direct stable orbits around the Moon. First, the location and size of apparently stable regions are searched for numerically, adopting the approach of temporary capture time presented in Vieira Neto & Winter (2001). The study is made in the framework of the planar, circular, restricted three-body problem, Earth-Moon-particle. Regions of the initial condition space whose trajectories are apparently stable are determined. The criterion adopted was that the trajectories do not escape from the Moon during an integration period of 10(4) days. Using Poincare surface of sections the reason for the existence of the two stable regions found is studied. The stability of such regions proved to be due to two families of simple periodic orbits, h1 and h2, and the associated quasi-periodic orbits that oscillate around them. The robustness of the stability of the larger region, h2, is tested with the inclusion of the solar perturbation. The size of the region decreases, but it is still significant in size and can be useful in spacecraft missions.

Time analysis for temporary gravitational capture - Stable orbits

In a previous work, Vieira Neto & Winter (2001) numerically explored the capture times of particles as temporary satellites of Uranus. The study was made in the framework of the spatial, circular, restricted three-body problem. Regions of the initial condition space whose trajectories are apparently stable were determined. The criterion adopted was that the trajectories do not escape from the planet during an integration of 10(5) years. These regions occur for a wide range of orbital initial inclinations (i). In the present work it is studied the reason for the existence of such stable regions. The stability of the planar retrograde trajectories is due to a family of simple periodic orbits and the associated quasi-periodic orbits that oscillate around them. These planar stable orbits had already been studied (Henon 1970; Huang & Innanen 1983). Their results are reviewed using Poincare surface of sections. The stable non-planar retrograde trajectories, 110 degrees less than or equal to i < 180, are found to be tridimensional quasi-periodic orbits around the same family of periodic orbits found for the planar case (i = 180 degrees). It was not found any periodic orbit out of the plane associated to such quasi-periodic orbits. The largest region of stable prograde trajectories occurs at i = 60 degrees. Trajectories in such region are found to behave as quasi-periodic orbits evolving similarly to the stable retrograde trajectories that occurs at i = 120 degrees.

Ceramic Primer Heat-Treatment Effect on Resin Cement/Y-TZP Bond Strength

The purpose of this study was to evaluate the effect of different heat-treatment strategies for a ceramic primer on the shear bond strength of a 10-methacryloyloxydecyl-dihydrogen-phosphate (MDP)-based resin cement to a yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramic. Specimens measuring 4.5 x 3.5 x 4.5 mm(3) were produced from Y-TZP presintered cubes and embedded in polymethyl methacrylate (PMMA). Following finishing, the specimens were cleaned using an ultrasound device and distilled water and randomly divided into 10 experimental groups (n=14) according to the heat treatment of the ceramic primer and aging condition. The strategies used for the experimental groups were: GC (control), without primer; G20, primer application at ambient temperature (20 degrees C); G45, primer application + heat treatment at 45 degrees C; G79, primer application + heat treatment at 79 degrees C; and G100, primer application + heat treatment at 100 degrees C. The specimens from the aging groups were submitted to thermal cycling (6000 cycles, 5 degrees C/55 degrees C, 30 seconds per bath) after 24 hours. A cylinder of MDP-based resin cement (2.4 mm in diameter) was constructed on the ceramic surface of the specimens of each experimental group and stored for 24 hours at 37 degrees C. The specimens were submitted to a shear bond strength test (n=14). Thermal gravimetric analysis was performed on the ceramic primer. The data obtained were statistically analyzed by two-way analysis of variance and the Tukey test (alpha=0.05). The experimental group G79 without aging (7.23 +/- 2.87 MPa) presented a significantly higher mean than the other experimental groups without aging (GC: 2.81 +/- 1.5 MPa; G20: 3.38 +/- 2.21 MPa; G100: 3.96 +/- 1.57 MPa), showing no difference from G45 only (G45: 6 +/- 3.63 MPa). All specimens of the aging groups debonded during thermocycling and were considered to present zero bond strength for the statistical analyses. In conclusion, heat treatment of the metal/zirconia primer improved bond strength under the initial condition but did not promote stable bonding under the aging condition.

Tosse, uma visão do otorrinolaringologista.

Persistent cough leads individuals to seek for medical assistance. Clinical investigation, however, may not reveal any alteration within the clinic's sphere of action. Often enough, some professionals treat the symptom as a disease, introducing several medicines, unsuccessfully. The author's experience, as an otolaryngologist, allows to state that many of these professionals ignore the upper aerodigestive tract as a cough-generator site. The present work discusses the alterations on the mentioned tract, which may provoke the cough reflex, reviewing, initially, the cough mechanism and the localization of the specific receptors. Cough is produce by stimulus at the receptor level or far from it. In upper and lower parts of the aerodigestive tract secretions may run to several directions. Secretion from the paranasal sinus is a frequent cause of cough. Acute sinusitis may occur insidiously bringing about the chronification of the inflammation with cough being the only great apparent symptom. Nasal and dental alterations favor sinusal infection. Signs and symptoms, even if minimum, may be detected through an accurate anamnesis. Nasal allergy, laryngitis, post nasal dripping and septal deviation may also produce cough. The ORL examination is, therefore, imperative, and no radiologic examination can substitute for it. An inadequate treatment, particularly of the sinusitis, may bring about a worsening and extension of the initial condition.

Interaction of pulses in the nonlinear Schrödinger model

A study was conducted on the interaction of two pulses in the nonlinear Schrodinger (NLS) model. The presence of different scenarios of the behavior depending on the initial parameters of the pulses, such as the pulse areas, the relative phase shift, the spatial and frequency separations were shown. It was observed that a pure real initial condition of the NLS equation can result in additional moving solitons.

Effects of latticeQCD EoS and continuous emission on some observables

Effects of lattice-QCD-inspired equations of state and continuous emission on some observables are discussed, by solving a 3D hydrodynamics. The particle multiplicity as well ν 2 are found to increase in the mid-rapidity. We also discuss the effects of the initial-condition fluctuations. © 2006 American Institute of Physics.

On the Chaotic Suppression of Both Ideal and Non-ideal Duffing Based Vibrating Systems, Using a Magnetorheological Damper

In this paper the dynamics of the ideal and non-ideal Duffing oscillator with chaotic behavior is considered. In order to suppress the chaotic behavior and to control the system, a control signal is introduced in the system dynamics. The control strategy involves the application of two control signals, a nonlinear feedforward control to maintain the controlled system in a periodic orbit, obtained by the harmonic balance method, and a state feedback control, obtained by the state dependent Riccati equation, to bring the system trajectory into the desired periodic orbit. Additionally, the control strategy includes an active magnetorheological damper to actuate on the system. The control force of the damper is a function of the electric current applied in the coil of the damper, that is based on the force given by the controller and on the velocity of the damper piston displacement. Numerical simulations demonstrate the effectiveness of the control strategy in leading the system from any initial condition to a desired orbit, and considering the mathematical model of the damper (MR), it was possible to control the force of the shock absorber (MR), by controlling the applied electric current in the coils of the damper. © 2012 Foundation for Scientific Research and Technological Innovation.

Advanced network reconfiguration system applied to CEMIG-D system

In the network reconfiguration context, the challenge nowadays is to improve the system in order to get intelligent systems that are able to monitor the network and produce refined information to support the operator decisions in real time, this because the network is wide, ramified and in some places difficult to access. The objective of this paper is to present the first results of the network reconfiguration algorithm that has been developed to CEMIG-D. The algorithm's main idea is to provide a new network configuration, after an event (fault or study case), based on an initial condition and aiming to minimize the affected load, considering the restrictions of load flow equations, maximum capacity of the lines as well as equipments and substations, voltage limits and system radial operation. Initial tests were made considering real data from the system, provided by CEMIG-D and it reveals very promising results. © 2013 IEEE.

Recuperação de perfis atmosféricos a partir de ocultação GPS: fundamentos, implementação e análise de resultados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)