In this thesis, using rigorous methods, we determine the low-lying energy-momentum spectrum of a lattice Quantum Chromodynamics model (QCD) in dimension 3 + 1, imaginary time and in the strong coupling regime. We consider a QCD model with the Wilson action, three quark avors and 4 X 4 Dirac spin matrices. Under these conditions, we reanalyze que question about the existence of baryon particles in the context of the Gell-Mann and Ne´eman Eightfold Way. Completing previous works, where the octet baryons where shown to exist, here we prove the existence of the decuplet baryons detected by showing the existence of isolated dispersion curves in the energy-momentum espectrum restricted to the subspace of the physical quantum-mechanical Hilbert H of the model, associated with states with an odd number of fermions. Besides, we obtain some smoothness properties veried by these curves, as well as analytical properties of the spectral measure for the two-baryon correlations. Also, the octet and the decuplet baryons are shown to be the only states in the odd subspace up to near the energy threshold of the meson-baryon bound state. Using the results obtained here, we can go up in the spectrum and validate some previously obtained results on the two-baryon bound state spectrum beyond the so called ladder approximation, for the complete model. / Nessa tese, usando métodos rigorosos, determinamos a parte inicial do espectro de energia-momento para o modelo de Cromodinâmica Quântica (QCD) na rede, em dimensão 3 + 1, com tempo imaginário e no regime de acoplamento forte. Consideramos o modelo de QCD com a ação de Wilson, três sabores de quarks e matrizes de spin de Dirac 4 X 4. Sob estas condições, reconsideramos a questão da demonstração da existência de bárions, no contexto do Eightfold Way de Gell-Mann e Ne ´eman. Complementando trabalhos anteriores onde a existência dos octetos de bárions foi demonstrada, aqui demonstramos a existência dos decupletos de bárions. Estas partículas são detectadas através de curvas de dispersão isoladas no espectro de energia-momento do modelo, considerando-se o subespaço H0, do espaço de Hilbert (quântico) físico H, com vetores com um número ímpar de férmions. Além disso, obtemos propriedades de suavidade destas curvas, assim como propriedade analíticas da medida espectral da correlação de dois bárions. Estes bárions são demonstrados ser os únicos estados espectrais no modelo, no subespaço ímpar, até o limiar de energia próximo do estado méson-bárion. Com os resultados obtidos nesta tese, podemos subir no espectro e validar, para o modelo completo, resultados espectrais envolvendo estados ligados de dois-bárion obtidos anteriormente na chamada aproximação escada (dominante).

Consideramos aqui a obtenção da parte inferior do espectro de energia-momento para modelos de Cromodinâmica Quântica (QCD) na rede, na formulação usando integral funcional com tempo imaginário e no regime de acoplamento forte, isto é, com o parâmetro de \"hopping\'\' κ > 0 satisfazendo 1 >> κ >> β > 0, onde β ≡ g-20 é o parâmetro de acoplamento da interação dos campos de calibre entre si, aqui definidos na álgebra de Lie $SU(3)$. Consideramos modelos de QCD com campos fermiônicos de quarks com um ou dois sabores (isospin) e em $2+1$ e $3+1$ dimensões, com diferentes dimensionalidades para matrizes de spin. Analisamos o setor mesônico: o espectro de uma e duas partículas. Detectamos estados de um méson e obtivemos suas aberturas de massa. Detectamos também, dependendo do modelo tratado, estados ligados de dois mésons. A existência de estados ligados de um méson e um bárion foi também analisada / We consider the energy-momentum spectrum of lattice quantum chromodynamics (QCD) models, using the functional integral formulation, with imaginary time and in the strong coupling regime. This regime corresponds to taking the hopping parameter $\\kappa>0$ satisfying $1>>\\kappa>>\\beta>0$, where $\\beta\\equiv g_0^$ is the coupling parameter among the gauge fields, here defined in the $SU(3)$ Lie algebra. We consider QCD models with fermionic quark fields with one and two flavors (isospin) and in $2+1$ and $3+1$ dimensions, and different types of spin matrices. We analyzed the mesonic sector: one and two-particle spectra. We detected one-meson states and obtained their mass splittings. Depending on the model, two-meson states were also obtained. The existence of bound states of one baryon and one meson was also analyzed

O trabalho tem como objetivo identificar a existência do efeito momento, de comprar ações com alto desempenho relativo no passado e vender as de baixo desempenho relativo no passado, e do efeito contrário, de comprar ações com baixo desempenho relativo no passado e vender as de alto desempenho relativo no passado. A análise considerou 662 ações negociadas na BM&FBOVESPA entre julho de 1994 e junho de 2015, considerando quatro períodos de formação (3, 6, 9 e 12 meses) e seis de manutenção (3, 6, 9 e 12, 18 e 24 meses) das carteiras. A metodologia adotada para o efeito momento utiliza a abordagem de Jegadeesh e Titman (1993) e, para o efeito contrário, optou-se por De Bondt e Thaler (1985). A partir da identificação das carteiras vencedoras e perdedoras, passou-se a calcular as diferenças dos retornos acumulados mensais com uma janela móvel para expurgar o viés de seleção. Das 24 estratégias analisadas, verificou-se que apenas uma não apresentou significância para o efeito momento e rejeitou-se a hipótese de existência do efeito contrário. Constatou-se o efeito momento em 23 estratégias, sendo que duas apresentaram desempenho médio mensal superior ao Ibovespa no mesmo período, nas carteiras \"12x3\" e \"9x6\", respectivamente, de 1,60% e 1,48%. As principais contribuições do trabalho foram a adoção de uma carteira móvel para a avaliação do desempenho das carteiras, o amplo período utilizado na análise e o grande número de ativos, o que proporciona maior robustez aos resultados encontrados. / The work aims to find momentum effect, that buys stocks with relative high return in the past and sells stocks with relative poor return in the past, and the contrarian effect, that buys stocks with relative poor return in the past and sells stocks with relative high performance in the past. The analysis included 662 stocks traded on BM&FBOVESPA between July 1994 and June 2015, considering four formation periods (3, 6, 9 and 12 months) and six holding periods (3, 6, 9 and 12, 18 and 24 months) for the portfolios. The methodology adopted for momentum effect uses the theory of Jegadeesh and Titman (1993) and the contrarian effect uses De Bondt and Thaler (1985) theory. From the identification of winners\' portfolios and losers\' portfolios, it was calculated the differences in monthly cumulative returns with a rolling window to purge the selection bias. Of the 24 strategies analyzed, it was found that only one has no significance for momentum effect, and the hypothesis of contrarian effect was rejected. Momentum effect was found in 23 strategies, and two had average monthly performance superior to Ibovespa in the same period in the \"12x3\" portfolios and \"9x6\" portfolios, respectively, 1.60% and 1.48%. The main contributions of this study was to adopt a rolling window for evaluating the performance of the portfolios, the extended period used in the analysis and the large number of stocks, which provides greater robustness to the results found

In this thesis, using rigorous methods, we determine the low-lying energy-momentum spectrum of a lattice Quantum Chromodynamics model (QCD) in dimension 3 + 1, imaginary time and in the strong coupling regime. We consider a QCD model with the Wilson action, three quark avors and 4 X 4 Dirac spin matrices. Under these conditions, we reanalyze que question about the existence of baryon particles in the context of the Gell-Mann and Ne´eman Eightfold Way. Completing previous works, where the octet baryons where shown to exist, here we prove the existence of the decuplet baryons detected by showing the existence of isolated dispersion curves in the energy-momentum espectrum restricted to the subspace of the physical quantum-mechanical Hilbert H of the model, associated with states with an odd number of fermions. Besides, we obtain some smoothness properties veried by these curves, as well as analytical properties of the spectral measure for the two-baryon correlations. Also, the octet and the decuplet baryons are shown to be the only states in the odd subspace up to near the energy threshold of the meson-baryon bound state. Using the results obtained here, we can go up in the spectrum and validate some previously obtained results on the two-baryon bound state spectrum beyond the so called ladder approximation, for the complete model. / Nessa tese, usando métodos rigorosos, determinamos a parte inicial do espectro de energia-momento para o modelo de Cromodinâmica Quântica (QCD) na rede, em dimensão 3 + 1, com tempo imaginário e no regime de acoplamento forte. Consideramos o modelo de QCD com a ação de Wilson, três sabores de quarks e matrizes de spin de Dirac 4 X 4. Sob estas condições, reconsideramos a questão da demonstração da existência de bárions, no contexto do Eightfold Way de Gell-Mann e Ne ´eman. Complementando trabalhos anteriores onde a existência dos octetos de bárions foi demonstrada, aqui demonstramos a existência dos decupletos de bárions. Estas partículas são detectadas através de curvas de dispersão isoladas no espectro de energia-momento do modelo, considerando-se o subespaço H0, do espaço de Hilbert (quântico) físico H, com vetores com um número ímpar de férmions. Além disso, obtemos propriedades de suavidade destas curvas, assim como propriedade analíticas da medida espectral da correlação de dois bárions. Estes bárions são demonstrados ser os únicos estados espectrais no modelo, no subespaço ímpar, até o limiar de energia próximo do estado méson-bárion. Com os resultados obtidos nesta tese, podemos subir no espectro e validar, para o modelo completo, resultados espectrais envolvendo estados ligados de dois-bárion obtidos anteriormente na chamada aproximação escada (dominante).

It is now believed that most, if not all, galaxies contain a supermassive black hole (SMBH) and that these play a crucial role in their host galaxies' evolution. Whilst accreting material, a SMBH (known as an active galactic nucleus, AGN, during this growth phase) releases energy which may have the effect of quenching star formation and constraining the growth of the galaxy. It is believed that AGNs can be divided into two broad fundamental categories, each with its own feedback mechanism. The radiative-mode of feedback occurs in gas-rich galaxies when substantial star formation is occurring and their young AGNs are growing rapidly through efficient accretion of cold gas. A fraction of the energy released by an AGN is transferred into the surrounding gas, creating a thermal "energy-driven" wind or pressure "momentum-driven" wind. Gas and dust may be expelled from the galaxy, so halting star formation but also cutting off the fuel supply to the AGN itself. The jet-mode occurs thereafter. The SMBH has now attained a large mass, but is accreting at a comparatively low level as gas slowly cools and falls back into the galaxy. The accretion process generates two-sided jets that generate shock fronts, so heating the gas surrounding the galaxy and partially offsetting the radiative cooling. This restricts the inflow of gas into the galaxy, so slowing the growth of the galaxy and SMBH. There are several convincing theoretical arguments to support the existence of these feedback mechanisms, although observational evidence has been hard to obtain. A new radio telescope - the Low Frequency Array (LOFAR) - recently started operations. LOFAR is especially suitable for investigating AGN feedback. It has been designed to allow exploration of low radio frequencies, between 10 and 240 MHz, which are particularly relevant for research into AGN activity. Also, with its large field-of-view and multi-beam capability, LOFAR is ideal for conducting extensive radio surveys. A project to image deeply the ELAIS-N1 field was started in May 2013. This thesis uses a number of surveys at different wavelengths, but particularly the low-frequency radio observations of the ELAIS-N1 field, to improve our knowledge of jet-mode AGN feedback and hence of the interplay between the complicated processes involved in galaxy formation and evolution. The more important pieces of research within the thesis are as follows: - A sample of 576 AGNs in the nearby universe was assembled and used to find a relationship between radio luminosity, X-ray luminosity and black hole mass. Moreover, the relationship is valid over at least 15 orders of magnitude in X-ray luminosity, strongly suggesting that the process responsible for the launching of radio jets is scale-invariant. - The established "Likelihood Ratio" technique was refined to incorporate colour information in order to optimally match the radio sources in the ELAIS-N1 field with their host galaxies. - The resulting catalogue was used to investigate ways in which radio sources can be matched automatically with their host galaxies (and so avoiding laborious visual examination of each source). The conclusions have helped the design of a pipeline for an extensive wide-area survey currently being conducted by the LOFAR telescope. - The catalogue was also used to investigate the evolution of jet-mode AGNs. This involved: deriving source counts; obtaining redshifts for each object; classifying the radio sources into the different populations of radiative-mode AGNs, jet-mode AGNs and star-forming galaxies; and using the above preparatory work in order to derive a luminosity function for jet-mode AGNs. - Key conclusions are that (1) feedback from jet-mode AGNs peaks at around a redshift of 0.75, (2) the space density of jet-mode AGNs declines steadily with redshift and (3) the typical luminosity of a jet-mode AGN increases steadily with redshift.

The present study assessed if embedding high probability responding (high-p) into an attentional cue, versus a general attentional cue (GA), would result in students with moderate and severe disabilities displaying differential responding for grade level science vocabulary word identification. Using an adapted alternating treatments design, three students with autism spectrum disorder received an intervention involving a GA cue and one with a high-p to determine which is more efficient. Hypothesized results are that the attentional cue with a high-probability motor sequence would be more effective for teaching vocabulary word identification.

Preference for one stimulus context over another and resistance to disruption within those contexts are a function of the conditions of reinforcement arranged within those contexts. According to behavioral momentum theory, these measures are converging expressions of the concept of response strength. Most studies have found that preference in concurrent chains and resistance to change are greater in contexts presenting higher rates or larger magnitudes of reinforcement. The present series of experiments attempted to extend behavioral momentum theory by examining whether differences in reinforcer type affect relative response strength with rats lever pressing for different types of food. In Experiment 1 of Chapter 2, several nonuniform disrupter types were examined that provided free access to a food type that was the same as one reinforcer type. Responding decreased more in the context presenting the same type of reinforcer as the disrupter, suggesting that many traditional disrupters (e.g., satiation) are inappropriate for examining how reinforcer type impacts response strength. Therefore, extinction was used throughout the remainder of the experiments to more uniformly disrupt responding across contexts. In Experiment 2 of Chapter 2, resistance to extinction was assessed when food pellets and a sucrose solution maintained responding across contexts. Moreover, relative reinforcer type was manipulated by changing the sucrose concentration across conditions. Relative response rates were systematically affected by changing sucrose concentration, but relative resistance to extinction was not. In Experiment 3 of Chapter 2, qualitative difference between reinforcers was enhanced and preference also was assessed to provide a converging measure of response strength. Preference and relative response rates were systematically affected, but relative resistance to extinction again was not. Finally, in Chapter 3, relative reinforcer rate and type were manipulated while assessing preference and resistance to extinction using the matching law. Preference, but not resistance to extinction, consistently was affected by changes in reinforcer rate and type. Systematic deviations in sensitivity and bias, however, suggested that different reinforcer types interacted with reinforcer rate. Overall, these findings suggest that the overall context of reinforcement, including interactions between different reinforcer types, should be considered when assessing preference and relative resistance to change.

Psychological disorders such as autism, obsessive-compulsive disorder, drug addiction, and attention-deficit/hyperactivity disorder involve atypically persistent behavior and atypical activity of the neurotransmitter dopamine. Behavioral momentum theory states that the persistence of behavior in a context is determined by the reinforcement received previously in that context. Contexts previously associated with higher rates of reinforcement yield greater persistence of behavior than contexts previously associated with lower rates of reinforcement. According to a prominent hypothesis in behavioral neuroscience, dopamine mediates the incentive salience of a stimulus. A synthesis of behavioral momentum theory and the incentive salience hypothesis proposes similar roles for dopamine activity and reinforcement in determining the persistence of behavior in a context. The aim of this dissertation was to determine the extent to which a history of dopamine modulation in a context affects the subsequent persistence of behavior in extinction and relapse. Three groups of rats were trained to press a lever for food in two alternating contexts of a multiple schedule. Following a stable baseline, rats entered a treatment phase in which they received a drug or saline injection before and after sessions in each context. In the drug context, rats received the indirect dopamine agonist amphetamine, dopamine D1 antagonist SCH 23390, or a combination of amphetamine and SCH 23390 prior to the session and a saline injection following the session. The injection schedule was reversed for the saline context such that rats received a saline injection prior to each session in the saline context and a drug injection following the session. During an extinction phase, access to food was withheld. Response-independent food was then provided in each context to trigger reinstatement of responding. A history of dopamine agonism in a context increased the relative persistence of behavior, while a history of dopamine antagonism at D1 receptors and a combination of dopamine agonism and dopamine antagonism had little impact on the relative persistence of behavior. Likewise, reinstatement was relatively greater in a context previously associated with dopamine agonism. This effect was blocked when dopamine agonism was preceded by D1 antagonism. A history of D1 antagonism alone did not affect reinstatement. These results suggest that dopamine plays a role in the persistence of behavior in extinction and relapse, but that different dopamine receptors mediate these effects.

L’écoulement entre deux cylindres coaxiaux, appelé l’écoulement de Couette-Taylor, a été étudié lorsque le cylindre intérieur tourne. Quatre dispositifs ont été utilisés avec différentes tailles d’entrefer. Les visualisations montrent l’évolution des motifs avec le nombre de Reynolds, Re. La variation du couple sur le cylindre intérieur a été déterminée en utilisant le pseudo-nombre de Nusselt, qui est une mesure du taux de dissipation d’énergie.Pour des faibles valeurs de Re, l’écoulement est laminaire et azimutal, et le couple est proportionnel à Re. Au-delà d’une valeur critique de Re, les rouleaux de Taylor apparaissent et la pente de variation du couple change brutalement. Pour de grandes valeurs de Re, les rouleaux deviennent turbulents et la pente du couple augmente à cause de la dissipation d’énergie turbulente. Le couple a été mesuré jusqu’à Re=45.000 et montre une dépendance avec le rapport de rayons des cylindres et du nombre de vortex. Avant le régime ultime de la turbulence, les états avec plus de rouleaux présentent un couple plus grand et la situation est inversée dans le régime ultime.Une étude du couple agissant sur le cylindre intérieur a été menée en présence d’un liquide viscoélastique contenant des polymères de grande masse molaire. En appliquant des cycles d’accélération-décélération de la rotation du cylindre intérieur, le couple présente une boucle d’hystérèse dont l’aire augmente avec la concentration de polymère. Les statistiques des fluctuations de la turbulence élastique ont été analysées. Le couple exercé par les vortex solitaires obtenus lors de la phase de décélération, avant la relaminarisation complète de l’écoulement, a été étudié. / The flow between two concentric cylinders, i.e., the Couette-Taylor flow, has been investigated when only the inner cylinder rotates. Four set-ups have been employed with 4 values of the radius ratio. Flow visualisations have been performed to analyse the evolution of the flow patterns with the Reynolds number, Re. The variation of the torque acting on the inner cylinder with different parameters has been quantified using the pseudo-Nusselt number, which measures the rate of energy dissipation in the flow.At low Re, the flow is laminar and azimuthal, and the torque is proportional to Re. Above a critical value of Re, Taylor vortices emerge in the flow and the slope of the torque changes drastically. At high values of Re, the vortices become turbulent and the increase rate of torque is enhanced due to the energy dissipation of turbulence. The torque measured up to Re=45 000 depends on the radius ratio of the cylinders and on the number of vortices. Below the ultimate regime of turbulence, flows containing larger number of vortices exert larger levels of torque; above it, flows containing larger number of vortices exert lower levels of torque.A specific study of the torque exerted on the inner cylinder has been carried out with viscoelastic fluids made of large-weight-molecule polymers. If acceleration-deceleration cycles of the rotation of the inner cylinder are applied, the torque exhibits a hysteretic loop, which increases with the polymer concentration. The statistics of the elastic turbulence fluctuations have been analysed. A special focus was made on the torque induced by the solitary vortices obtained in the deceleration phase, before the flow relaminarisation.

本研究採2003年12月至2010年6月上市上櫃公司為研究樣本，檢驗當期投資人情緒、公司治理、及動能投資策略對下期股價獲利的影響，與先前研究不同之處在於，投資人情緒使用世新大學投資人情緒資料庫所提供之「投資人情緒指數」。實證結果為: 1、當期投資人情緒悲觀會使得當期股價低估，而使下期股價向上修正時有較高的報酬率。 2、公司治理佳的股票報酬率顯著大於公司治理劣的股票報酬率。 3、過去股價報酬率較高者未來也有較高的獲利，反之則較低。 4、投資人情緒相較於公司治理及動能策略而言，為主要的影響股價的因素。 5、金融海嘯時，投資人情緒悲觀仍使下期股價有較高的報酬率，但公司治理劣者報酬率顯著大於公司治理佳者。