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A bstract We show that classical, non-supersymmetric Yang-Mills theories coupled to spin-1/2 and spin-0 elementary matter fields, in (3 + 1)-dimensional Minkowski space-time, possess exact structures that resemble integrability, with an infinite number of conserved charges in involution. Such structures live in the space of non-abelian electric and magnetic charges, and are based on flat connections in generalized loop spaces, presenting an R -matrix, and Sklyanin relation. We present two novel symmetries of Yang-Mills theories. The first one corresponds to global transformations generated by the infinity of those conserved charges under the Poisson brackets. The gauge and matter fields, as well as Wilson lines and fluxes, have interesting transformation laws under such a global symmetry. The second one corresponds to symmetries of the integral Yang-Mills equations, which lead to the conserved charges. They generate an infinite-dimensional group, where the elements are holonomies of connections on the loop space of functions from the circle S 1 to the space-time. Our approach certainly applies to the Standard Model of the Fundamental Interactions. The conserved charges are gauge invariant, and so, in the case of QCD, they are color singlets and perhaps are not confined. Therefore, the hadrons may carry such charges. Our results open up the way for the construction of non-perturbative methods for Yang-Mills theories.

A bstract We use ideas of generalized self-duality conditions to construct real scalar field theories in (1 + 1)-dimensions with exact self dual sectors. The approach is based on a pre-potential U that defines the topological charge and the potential energy of these theories. In our algebraic method to construct the required pre-potentials we use the representation theory of Lie groups. This approach leads naturally to an infinite set of degenerate vacua and so to topologically non-trivial self-dual solutions of these models. We present explicit examples for the groups SU(2), SU(3) and SO(5) and discuss some properties of these solutions.

The fundamental vacuum state of quantum fields, related to Minkowski space, produces divergent fluctuations that must be suppressed in order to bring reality to the description of physical systems. As a consequence, negative vacuum expectation values of classically positive-defined quantities can appear. This has been addressed in the literature as subvacuum phenomenon. Here it is investigated how a scalar charged test particle is affected by the vacuum fluctuations of a massive scalar field in D + 1 spacetime when the background evolves from empty space to a thermal bath, and also when a perfectly reflecting boundary is included. It is shown that when the particle is brought into a thermal bath it gains an amount of energy by means of positive dispersions of its velocity components. The magnitude of this effect is dependent on the temperature and also on the field mass. However, when a reflecting wall is inserted, dispersions can be positive or negative, showing that subvacuum effect happens even in a finite temperature environment. Furthermore, a remarkable result is that temperature can even improve negative velocity fluctuations. The magnitude of the residual effects depends on the switching interval of time the system takes to evolve between two states.

A bstract If a scalar field theory in (1+1) dimensions possesses soliton solutions obeying first order BPS equations, then, in general, it is possible to find an infinite number of related field theories with BPS solitons which obey closely related BPS equations. We point out that this fact may be understood as a simple consequence of an appropriately generalised notion of self-duality. We show that this self-duality framework enables us to generalize to higher dimensions the construction of new solitons from already known solutions. By performing simple field transformations our procedure allows us to relate solitons with different topological properties. We present several interesting examples of such solitons in two and three dimensions.

A bstract We propose a new Skyrme-like model with fields taking values on the sphere S 3 or, equivalently, on the group SU(2). The action of the model contains a quadratic kinetic term plus a quartic term which is the same as that of the Skyrme-Faddeev model. The novelty of the model is that it possess a first order Bogomolny type equation whose solutions automatically satisfy the second order Euler-Lagrange equations. It also possesses a lower bound on the static energy which is saturated by the Bogomolny solutions. Such Bogomolny equation is equivalent to the so-called force free equation used in plasma and solar Physics, and which possesses large classes of solutions. An old result due to Chandrasekhar prevents the existence of finite energy solutions for the force free equation on the entire three-dimensional space . We construct new exact finite energy solutions to the Bogomolny equations for the case where the space is the three-sphere S 3 , using toroidal like coordinates.

Novel drug delivery systems, such as solid lipid nanoparticles (SLN), have been proposed to reduce retinoic acid (RA)-induced skin irritation. However, one question still remains: could it be accomplished without reducing efficacy? To evaluate this question the comedolytic effects and epidermal thickening of RA-loaded SLN were compared to the conventional RA formulations (gel or cream), as well as the potential of these formulations to induce skin irritation. The comedolytic effects and epidermal thickening of these formulations, both containing RA at 0.01 or 0.05%, were investigated in a rhino mouse model, while the studies of RA-induced skin irritation were evaluated through rabbit skin irritation tests and in the rhino mouse model. RA-loaded SLN, as compared to the placebo, produced a comedolytic effect with a significant reduction of the utricle diameter, which proved to be similar to that observed for marketed gels or creams regardless of the RA concentration. RA formulations (SLN or marketed cream) also induced an epidermal proliferation leading to a thickened epidermis in treated animals. In both animals studied (rhino mice and rabbits), the RA-loaded SLN, when compared to conventional formulations, promoted a significant reduction in RA-induced skin irritation (erythema and scaling). Then, RA-loaded SLN represents an interesting alternative to reduce RA-induced skin irritation without reducing efficacy, and constitutes an innovative approach for the topical treatment of acne with RA.

Transporting live fish is a common practice in fish farming, and is certainly one of the main problems that affect fish homeostasis. In this scenario, the use of natural additives has shown promise in improving fish resistance to adverse situations. This study aimed to assess the impact of Ocimum gratissimum L. essential oil (OGEO) on water quality, hematological parameters, and residue levels in the plasma, fillet, and liver of juvenile piraputanga (Brycon hilarii) during a two-hour transportation period. The fish were divided into plastic bags (4 L) and exposed to three different OGEO concentrations (10, 20, and 30 mg L-1), while a control group received no OGEO (three repetitions each). After the two-hour transportation, blood samples were collected, as well as portions of the fillet and liver for quantifying essential oil compounds, which were also measured in the plasma. Oxygen levels remained high throughout the transportation period, in all groups, while the pH decreased. Hemoglobin, MCHC, and MCH increased in fish exposed to OGEO concentrations of 20 and 30 mg L-1, compared to the control group. However, lymphocyte counts and the concentrations of essential oil compounds in plasma, fillet, and liver increased with higher OGEO concentrations. The use of 10 mg L-1 OGEO in the two-hour transport water is promising to ensure the survival and well-being of Brycon hilarii juveniles (weighing 16 g), showing to be safe and effective. The residual concentration of eugenol the major compound of OGEO in the fillet remains below the maximum limit of the recommended daily intake.

Abstract This study evaluated the use of the essential oil of Lippia origanoides (EOLO) as an anesthetic for juvenile pacu, Piaractus mesopotamicus. Two experiments were performed. In Experiment I, anesthetic induction and recovery times and ventilatory frequency (VF) were determined for fish (n= 48; 29.94 ± 6.69 g) exposed to different EOLO concentrations [0 (control - 4000 µL alcohol L-1), 25, 50, 100, 200 and 400 µL L-1]. From the responses obtained in Experiment I, the EOLO concentrations of Experiment II (n= 36; 29.25 ± 5.90 g) were determined, which evaluated the effects of 0 (control - 2000 µL alcohol L-1), 50 (outside recommended induction and recovery times) and 200 µL L-1 (within recommended induction and recovery times) by analyzing immunohematological and biochemical parameters at different collection times (1 h and 24 h post-induction). Fish survival was 100% in both experiments. The EOLO concentration of 25 µL L-1 was not able to induce deep anesthesia in the animals, while the concentration of 200 µL L-1 showed induction and recovery times within the range indicated for fish and was efficient at reducing VF during induction. No differences were observed in immunohematological and biochemical parameters among concentrations, but differences were observed in comparisons between collection times. Nonetheless, blood variables returned to levels considered normal for the species in approximately 24 hours. Therefore, an EOLO concentration of 200 µL L-1 can be considered safe for use prior to biometric management of P. mesopotamicus. Resumo Este estudo avaliou o uso do óleo essencial de Lippia origanoides (EOLO) como anestésico para juvenis de pacu, Piaractus mesopotamicus. Foram realizados dois experimentos. No Experimento I foram determinados os tempos de indução e recuperação anestésica e a frequência ventilatória (FV) para peixes (n= 48; 29,94 ± 6,69 g) expostos a diferentes concentrações de EOLO [0 (controle - 4000 µL álcool L-1), 25, 50, 100, 200 e 400 µL L-1]. A partir dos resultados obtidos no Experimento I foram determinadas as concentrações de EOLO do Experimento II (n= 36; 29,25 ± 5,90 g), na qual avaliou os efeitos de 0 (controle - 2.000 µL álcool L-1), 50 (fora da indução recomendada e tempos de recuperação) e 200 µL L-1 (dentro dos tempos de indução e recuperação recomendados), sob os parâmetros imunohematológicos e bioquímicos em diferentes tempos de coleta (1 hora e 24 horas pós-indução). A sobrevivência dos peixes foi de 100% em ambos os experimentos. A concentração de EOLO de 25 µL L-1 não foi capaz de induzir anestesia profunda nos animais, enquanto a concentração de 200 µL L-1 apresentou tempos de indução e recuperação dentro da faixa indicada para peixes e foi eficiente na redução da FV durante a indução. Não foram observadas diferenças nos parâmetros imunohematológicos e bioquímicos entre as concentrações, mas foram observadas diferenças nas comparações entre os tempos de coleta. Porém, a maioria das variáveis sanguíneas retornaram a níveis considerados normais para a espécie 24 horas após a anestesia. Portanto, uma concentração EOLO de 200 µL L-1 pode ser considerada segura para uso antes do manejo biométrico de P. mesopotamicus.

A bstract Following our attempts to define quasi-integrability in which we related this concept to a particular symmetry of the two-soliton function we check this condition in three classes of modified sine-Gordon models in (1 + 1) dimensions. We find that the numerical results seen in various scatterings of two solitons and in the time evolution of breather-like structures support our ideas about the symmetry of the field configurations and its effects on the anomalies of the conservation laws of the charges.

Matrix metalloproteinases (MMPs) are involved in cardiac remodelling. We examined whether MMP-2 genetic polymorphisms are associated with hypertension and left ventricular (LV) remodelling in hypertensive patients. We studied 160 hypertensive patients and 123 healthy controls. Echocardiography was performed in all patients and the C −1306 T (rs243865) and C −735 T (rs 2285053) MMP-2 polymorphisms were analysed. Haplo.stats analysis was used to evaluate whether MMP-2 haplotypes are associated with hypertension and with extremes in LV mass index (LVMI). Multiple linear regression analysis was performed to assess whether MMP-2 genotypes or haplotypes affect LVMI and other echocardiography parameters. The C −1306 T ‘CC’ genotype was associated with reduced LVMI and LV end-diastolic diameter (EDD) ( P =0.0365 and P =0.0438, respectively). The haplotype ‘C, C’ was associated with reduced LVMI and EDD ( P =0.0278 and P =0.0322, respectively). The comparison of upper and lower extremes of the LVMI phenotype showed that the ‘C, C’ haplotype was more common in the lower LVMI group ( P =0.0060), whereas the ‘T, C’ haplotype was more common in the higher quartile of LVMI ( P =0.0187), and this haplotype was associated with increased risk of higher LVMI values (odds ratio=3.5121, 95% confidence interval=1.3193–9.3494). The findings suggest that MMP-2 polymorphisms affect hypertension-induced LV remodelling.