Examining the evolution of the maximum of valence quark distribution, qV, weighted by Bjorken x, h(x,t)≡xqV(x,t), it is observed that h(x,t) at the peak becomes a one-parameter function; h(xp,t)=Φ(xp(t)), where xp is the position of the peak, t=logQ2, and Q2 is the resolution scale. This observation is used to derive a new model-independent relation which connects the partial derivative of the valence parton distribution functions (PDFs) in xp to the quantum chromodynamics (QCD) evolution equation through the xp derivative of the logarithm of the function Φ(xp(t)). A numerical analysis of this relation using empirical PDFs results in an observation of the exponential form of the Φ(xp(t))=h(xp,t)=CeDxp(t) for leading to next-to-next leading order approximations of PDFs for the range of Q2, covering four orders in magnitude. The exponent, D, of the observed “height-position” correlation function converges with the increase in the order of approximation. This result holds for all the PDF sets considered. A similar relation is observed also for the pion valence quark distribution, indicating that the obtained relation may be universal for any non-singlet partonic distribution. The observed “height-position” correlation is used also to indicate that no finite number of exchanges can describe the analytic behavior of the valence quark distribution at the position of the peak at fixed Q2.

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Plant-based protein sources, such as soybean, are widely used in fish nutrition due to their market availability, wide distribution and acceptable nutritional quality. However, in some fish species, soybean meal-based diets cause gut inflammation, decreasing both nutrient absorption and growth rates. A suitable alternative to avoid these problems could be the application of additives with anti-inflammatory activity to the diet. In this study, an Aloe vera (Aloe barbadensis Miller, AV) extract was analyzed as a dietary additive to reduce the gut inflammation in Atlantic salmon (Salmo salar) fed with soybean meal (SBM) diet. Fish were distributed in four duplicated groups and fed 28 days with fish meal control diet (FM), AV inclusion diet (AV), FM diet supplemented with AV (FM+AV), SBM diet to induce enteritis and SBM+AV. The fish gut response to these treatments was analyzed in distal intestine by histopathological scores, tissue morphometric measurements and immune gene expression parameters. The score results in fish fed with SBM-based diet clearly showed enteritis, meanwhile fish fed with AV supplemented diet significantly reduced the intestinal SBM signs of damage. These findings were associated to reduction of goblet cells number, lamina propria thickness and sub-epithelial mucosa size, with a significant decrease on pro-inflammatory cytokine il-1β to basal levels, similar to those present in fish fed FM diets. In conclusion, the administration of AV in salmon diet showed a protective intestinal activity against the detrimental effects of SBM, opening the possibility to improve its use as a feed additive in aquafeeds.

Electro-disintegration of the deuteron at large 𝑄 2 currently represents on of the most promising reactions which allows to probe the bound nuclear state at internal momenta comparable to the rest mass of the nucleon. Large internal momentum in this case makes non-nuncleonic states energetically more feasible and the question that we address is what are the signatures that will indicate the existence of such states in the ground state of the nuclear wave function. To probe such states we developed a light-front formalism for relativistic description of a composite pseudovector system in which emerging proton and neutron are observed in electro-disintegration reaction. In leading high energy approximation our calculations show the possibility of the existence of a new "incomplete" P-state-like structure in the deuteron at extremely large internal momenta. The incompleteness of the observed P-state violates the angular condition for the momentum distribution, which can happen only if the deuteron contains non-nucleonic structures, such as ΔΔ, 𝑁 * 𝑁 or hidden color components. Because such states have distinctive angular momentum (𝑙 = 1) they significantly modify the polarization properties of the deuteron wave function. As a result in addition to angular anisotropy of the LF momentum distribution of the nucleon in the deuteron one predicts strong modification of the tensor polarization asymmetry of the deuteron beyond the S-and D-wave predictions at large internal momenta in the deuteron.

We calculate the cross section of the electron scattering from a bound nucleon within light-front approximation. The advantage of this approximation is the possibility of systematic account for the off-shell effects which become essential in high energy electro-nuclear processes aimed at probing the nuclear structure at small distances. We derive a new dynamical parameter which allows to control the extent of the "off-shellness" of electron -bound-nucleon electromagnetic current for different regions of momentum transfer and initial light-cone momenta of the bound nucleon. The derived cross section is compared with the results of other approaches in treating the off-shell effects in electron-nucleon scattering.