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•Productivity of antioxidant peptides obtained from red tilapia viscera hydrolysates increases with the use of cross-flow filtration using ceramic membranes.•Response Surface Methodology can be used for optimize the cross-flow filtration of red tilapia viscera hydrolysates.•The fraction of hydrolysates of red tilapia viscera lower to 3 kDa contains the peptides with major antioxidant activity.•Cross-flow filtration of hydrolysates of red tilapia viscera is affected by pH.

Metal-chelating peptides represent an alternative for overcoming iron deficiencies, a common nutritional disease affecting populations worldwide. This study explored the iron-chelating activity of California red worm hydrolysates (WH) and its fractions. WH was obtained by hydrolysis with Alcalase 2.4 L and fractionated using a ceramic membrane with molecular weight cutoff 3 kDa. Both the complete hydrolysate and its fractions were assessed for their in-vitroiron-chelating activity and their ability to improve iron bioavailability through ferritin formation by differentiated Caco-2 cells assay. Finally, peptides in the fraction with the highest activity were sequenced by LC-MS/MS analysis and molecular docking was performed to elucidate the chelation mechanism. The findings reveal that the smallest fraction (F < 3 kDa) exhibits the most potent iron-chelating activity with IC50value like carnosine. Moreover, in intestinal-like differentiated Caco-2 cells, this fraction enhances iron bioavailability in a remarkable 77.9% in comparison to FeSO4alone. On the other hand, the peptide SLLDDRLDEK identified in this fraction presents the lowest value of affinity energy (−1.5 kcal/mol) and exhibits specific interactions with iron, allowing iron ions to be trapped within its structure. These results underscore the potential of F < 3 kDa fractions from WH as promising candidates for increasing iron bioavailability and addressing iron deficiency and related health concerns.

Orlicz-type modules are module analogues of classical Orlicz spaces. We study duality and stable compactness in Orlicz-type modules. We characterize the conditional Köthe dual of an Orlicz-type module as the space of all σ-order continuous module homomorphisms. We find an order continuity criterion for stable compactness in Orlicz-type modules. As an application, we obtain a robust representation result for conditional risk measures on Orlicz spaces.

Background: In modern society, there is a tendency to consume products with natural origins and minimum chemical additives. This has encouraged the replacement of synthetic antioxidants for the ones obtained from natural sources, such as the antioxidants acquired from enzymatic protein hydrolysates. Objective: In this study, the process of enzymatic hydrolysis of proteins from bovine plasma, which produces hydrolysates with an Antioxidant Capacity (AC), was scaled up from 1 to 5 L. Methods: An experimental design was developed in 1 L to evaluate the effect of the Substrate concentration (So) on the time needed to reach a Degree of Hydrolysis (DH) of 20% as well as the AC. Results: The best conditions in the 1 L reactor controlled by a Titrando 842 were transferred to 5L in a BioFlo310 reactor. These conditions were achieved at a ratio of 80g/L of the substrate and 0.89 AU of Alcalase 2.4L/g of the substrate in order to obtain a level of 16.36 ± 0.21min of the 20% of DH and antioxidant capacity of 58.98 ± 1.80%. Conclusion: The results showed that DH depends significantly on So, while the antioxidant capacity only depends on the DH. Additionally, the dimensional analysis using Re as a scaling criterion allowed us to obtain the same results in the model (1 L) and the prototype (5 L).

Colletotrichumspecies are the most important postharvest spoilage fungi of papaya fruit. The objective of this research was to evaluate the effect of temperature and relative humidity on growth rate and time for growth to become visible of five strains of Colletotrichum gloeosporioidesisolated from papaya fruit in a complex medium. As a primary model, the radial growth rates were estimated using the Baranyi and Roberts model in papaya agar. The Solver MS Excel function was used to obtain the time to visible mycelium (tv). Secondary models obtained with the Rosso et al. cardinal model of inflection were applied to describe the effect of temperature on the growth rate (μ). The Arrhenius-Davey model was used to model tv. The obtained models seem to be satisfactory for describing both μ and tv. The relative humidity had an effect on μ and tvfor all tested C. gloeosporioidesisolates, but no model accurately described the behavior of the fungus. External validation of models was performed with papaya fruit. Growth models were developed with the same models used in vitro. The bias and the accuracy factors as indices for performance evaluation of predictive models in food microbiology as a function of temperature and RH were 1.22 and 1.33, respectively, for μ and 1.18 and 1.62, respectively, for tv,indicating accurate predictions. The supply chain of papaya is complex and requires constant conditions, and poor conditions can result in damage to the fruit. Knowledge of the behavior of C. gloeosporioideson papaya fruit and application of the developed models in the supply chain will help to establish transport control strategies to combat these fungi. This research has contributed to development of the first models of growth for C. gloeosporioidesin Mexico.

A review of the gene expression relating to capsaicinoid biosynthesis was carried out, in different species and varieties, within the Capsicumgenus. The results were obtained using different molecular approaches with a variety of species of Capsicumgenus (mainly C. frutescens L.,C. chinenseJacq. and C. annuumL.). The analysis of these results indicated that some genes determine the pungency or non-pungency in these species, mainly by recessive or non-functional alleles. In addition, the level of expression of other genes modulates the level of capsaicinoids. Environmental factors and abiotic stress influence the expression of candidate genes, impacting the capsaicinoid biosynthesis and, in turn, the fruit pungency. Other factors such as fruit tissue (placenta, pericarp) and plant varieties also influence the transcriptomic profile. Finally, the transcriptome approaches demonstrated gene regulation in the capsaicinoid biosynthesis pathway, and interestingly, in other genes responsible for the phenylpropanoids synthesis and the amino acid precursor synthesis, which also play a role in the capsaicinoids accumulation.

Background: Fish is an essential source of nutrients for human nutrition due to the composition of proteins, vitamins, and minerals, among other nutrients. Enzymatic hydrolysis represents an alternative for the use of by-products of the aquaculture industry. Objective: We propose to evaluate the effect of stirring speed, temperature, and initial protein concentration on the degree of hydrolysis of proteins and antioxidant activity of red tilapia (Oreochromis spp.) viscera hydrolysates. Methods: The effect of stirring speed, temperature, and initial protein concentration on the degree of hydrolysis of proteins and antioxidant activity was evaluated using an experimental design that was adjusted to a polynomial equation. The hydrolysate was fractioned to determine the antioxidant activity of the fractions, and functional properties were also measured. Results: Stirring speed and protein concentration presented a statistically significant effect (p <0.05) on all the response variables. However, the temperature did not present a statistically significant effect on the degree of hydrolysis. Discussion: The best conditions of hydrolysis were stirring speed of 51.44 rpm, a temperature of 59.15°C, and the protein concentration of 10 g L-1. The solubility of the hydrolysate protein was high at different pH, and the hydrolysate fraction with the highest antioxidant activity has a molecular weight <1 kDa. Conclusion: The degree of hydrolysis and the biological activity of red tilapia viscera hydrolysates (Oreochromis spp.) are affected by temperature, substrate concentration, and stirring speed. The optimal conditions of hydrolysis allowed to obtain a hydrolysate with antioxidant activity are due to the peptides with low molecular weight.

Background: The animal blood that is produced in a slaughterhouse is a potential source of inexpensive proteins used in the food industry around the world. However, 60% of it is surplus, and it ends with a negative environmental impact. Introduction: The enzymatic hydrolysis of proteins represents a good way to produce peptides with different biological activities. Methods: Enzymatic hydrolysis of bovine plasma with subtilisin at an alkaline pH and 61.5°C was performed using the pH-stat method. Experiments were conducted considering the effects of a high initial substrate concentration (So) and the enzyme/substrate ratio (E/S) minimizing the processing time necessary to obtain a specific degree of hydrolysis (DH). Results: The best conditions obtained were 42 g/L of So and 0.89 AU/g substrate of E/S until a DH of 20% in 11,1 ± 1,1 min was achieved to the tested conditions, which result in a fitted empirical polynomial equation of degree 3. Conclusion: A kinetic equation is established to relate the DH and the reaction time to a relative error of less than 5% in the fit, to obtain a good antioxidant product in an industrially interesting time. Additionally, the results suggest a good adjustment of the data with a determination coefficient (R2) of 0.9745 in validation.

The control of solar thermal systems is challenging due to the non-linear dynamic behaviour of the heat transfer process occurring at the receivers, such as direct steam generation. Model predictive controllers can outperform classical control approaches by incorporating nonlinear model behaviour and constraints. This study presents a model predictive controller based on a piecewise affine approximation of a direct steam generation receiver that explicitly incorporates constraints. Simulations in this study show that a piecewise affine approximation based model predictive controller outperforms both a MPC based on a linear approximation of the receiver and a classic state-space controller.

We present an implementation of Wilson's renormalization group and a continuum limit tailored for loop quantization. The dynamics of loop-quantized theories is constructed as a continuum limit of the dynamics of effective theories. After presenting the general formalism we show as a first explicit example the 2D Ising field theory, an interacting relativistic quantum field theory with local degrees of freedom quantized by loop quantization techniques.

We present an interpretation of loop quantization in the framework of lattice gauge theory. Within this context the lack of appropriate notions of effective theories and renormalization group flow exhibit loop quantization as an incomplete framework. This interpretation includes a construction of embedded spin foam models which does not rely on the choice of any auxiliary structure (e.g. triangulation) and has the following straightforward consequences:

1. The values of the coupling constants need to be those of an UV-attractive fixed point.
2. The kinematics of canonical loop quantization and embedded spin foam models are compatible.
3. The weights assigned to embedded spin foams are independent of the 2-polyhedron used to regularize the path integral, |J|_x = |J|_x'.
4. An area spectrum with edge contributions proportional to l_PL²(j + 1/2) is not compatible with embedded spin foam models and/or canonical loop quantization.

We investigated the effects of salinity stress-relief on the growth and mineral composition (leaf and root) of one-year-old seedlings of Cleopatra mandarin (Citrus reticulata Blanco) and Sour orange (Citrus aurantium [L]). Salinization reduced plant dry weight more in Sour orange than in Cleopatra mandarin plants, although there was no correlation between Cl and Na concentration in leaves and shoot fresh weight reduction. We observed that regulation of Na+ and Cl– uptake and transport from root to shoot appear to involve different mechanisms which break down during a long period of salinization. Salinity induced a decrease in K+, Ca2+ and total N in Cleopatra mandarin leaves and an increase in K+ in Sour orange leaves. Growth of both cultivars was not recovered totally in the relief period, since relative growth rates of recovered plants were lower than for control plants after 60 days of relief.

Polypeptides encoded by plastid ndhgenes form a complex (Ndh) which could reduce plastoquinone with NADH. Through a terminal oxidase, reduced plastoquinone would be oxidized in chlororespiration. However, isolated Ndh complex has low activity with plastoquinone and no terminal oxidase has been found in chloroplasts, thus the function of Ndh complex is unknown. Alternatively, thylakoid hydroquinone peroxidase could oxidize reduced plastoquinone with H2O2. By immunoaffinity chromatography, we have purified the plastid Ndh complex of barley (Hordeum vulgareL.) to investigate the electron donor and acceptor specificity. A detergent-containing system was reconstructed with thylakoid Ndh complex and peroxidase which oxidized NADH with H2O2in a plastoquinone-dependent process. This system and the increases of thylakoid Ndh complex and peroxidase activities under photooxidative stress suggest that the chlororespiratory process consists of the sequence of reactions catalyzed by Ndh complex, peroxidase (acting on reduced plastoquinone), superoxide dismutase, and the non-enzymic one-electron transfer from reduced iron-sulfur protein (FeSP) to O2. When FeSP is a component of cytochrome b6·fcomplex or of the same Ndh complex, O2may be reduced with NADH, without requirement of light. Chlororespiration consumes reactive species of oxygen and, eventually, may decrease their production by lowering O2concentration in chloroplasts. The common plastoquinone pool with photosynthetic electron transport suggests that chlororespiratory reactions may poise reduced and oxidized forms of the intermediates of cyclic electron transport under highly fluctuating light intensities.

A zymographic screening of peroxidases (EC 1.11.1.7) capable of oxidizing 4-hydroxystilbene was carried out by means of the peroxidase-catalyzed oxidative coupling of 4-hydroxystilbene and 4-aminoantipyrine. This screening reveals that only a few isoperoxidases are active in oxidizing 4-hydroxystilbene to viniferin-type compounds in in vitro cultures of grapevine. Unlike total peroxidase activity measured with 4-methoxy-a-naphthol, the levels of total peroxidase activity measured using 4-hydroxystilbene are related to disease resistance against downy mildew in axillary bud cultures of Vitis vinifera and (Vitis vinifera x Vitis rupestris) x Vitis riparia. From this observation, and using the above zymographic assay, it was found that a 4-hydroxystilbene-oxidizing isoperoxidase was overexpressed in both leaves and stems of the hybrid in relation to the increase in disease resistance of this species. These results suggest that constitutive 4-hydroxystilbene-oxidizing isoperoxidases may participate through their role in viniferin synthesis in the constitutive resistance mechanism that grapevines show against downy mildew.

The canonical quantization of diffeomorphism invariant theories of connections in terms of loop variables is revisited. Such theories include general relativity described in terms of Ashtekar-Barbero variables and extension to Yang-Mills fields (with or without fermions) coupled to gravity. It is argued that the operators induced by classical diffeomorphism invariant or covariant functions are respectively invariant or covariant under a suitable completion of the diffeomorphism group. The canonical quantization in terms of loop variables described here, yields a representation of the algebra of observables in a separable Hilbert space. Furthermore, the resulting quantum theory is equivalent to a model for diffeomorphism invariant gauge theories which replaces space with a manifestly combinatorial object.

The identification of human violence determinants has sparked multiple questions from different academic fields. Innovative methodological assessments of the weight and interaction of multiple determinants are still required. Here, we examine multiple features potentially associated with confessed acts of violence in ex-members of illegal armed groups in Colombia (N = 26,349) through deep learning and feature-derived machine learning. We assessed 162 social-contextual and individual mental health potential predictors of historical data regarding consequentialist, appetitive, retaliative, and reactive domains of violence. Deep learning yields high accuracy using the full set of determinants. Progressive feature elimination revealed that contextual factors were more important than individual factors. Combined social network adversities, membership identification, and normalization of violence were among the more accurate social-contextual factors. To a lesser extent the best individual factors were personality traits (borderline, paranoid, and antisocial) and psychiatric symptoms. The results provide a population-based computational classification regarding historical assessments of violence in vulnerable populations.

This article focuses on the commentary and web casting aspects of the 2007 Junior World Orienteering Championships (JWOC). Information regarding the channels used to propagate the commentators' voices and the music are given. Details related to the mixer output and the SHOUTcast server are presented. Also included are the two most popular events at the JWOC, the high tech requirements of the coverage, and the sponsorship agreement with Clear Networks.

Different media were tested (MS and Knudson), as well as diverse organic and inorganic substrates (peat, maquique, vermiculite and perlite), for the germination of spores of three species of wild ferns with ornamental potential -- Adiantum and Asplenium. [ABSTRACT FROM AUTHOR]