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The recently discovered twist-bend nematic phase, Ntb, is a non-uniform equilibrium nematic phase that presents a spontaneous bend with a precession of the nematic director,n, on a conical helix with a tilt angleθand helical pitchP. The stability of the Ntbphase has been recently demonstrated from the elastic point of view by extending the Frank elastic energy density of the nematic phase to include the symmetry element of the helical axis,t. In the present article, we investigate the influence of an external bulk field (magnetic or electric) on the Ntbphase. Using symmetry arguments we derive the expression for the flexoelectric polarisation in twist-bend nematic phases. We show that, besides the standard contribution related to the spatial variation of the nematic director, two new contributions connected with the existence of the helical axis appear. In the ground state, where the nematic deformation is a pure heliconical deformation, the new contribution vanishes identically, and the total flexoelectric polarisation is perpendicular to the nematic director. Furthermore, as an example, we study the role of an external magnetic field applied parallel to the helical axis for a material with positive magnetic susceptibility anisotropy. We show that the field modifies the range of values of the coupling parameter between the director and the helical axis, thus shifting the interval of values for which this coupling results in the Ntbphase. [ABSTRACT FROM PUBLISHER]

A reinervação dos nervos periféricos pode ser realizada através de anastomoses término - terminais ou término-laterais, e este fenômeno tem sido amplamente estud ado. As anastomoses nervosas término-laterais tem sido utilizadas com pouca freqüência em relação as anastomoses término-terminais e contestada por alguns autores quanto a possibilidade de reinervação, quando a integridade do epineuro é mantida. Devido a estas divergências, estudou-se o efeito do epineuro na reinervação em anastomoses término-laterais, em ratos. Foram utilizados 20 ratos Wistar, adultos, distribuídos em dois grupos (A e B). No grupo A, 10 animais foram submetidos à secção do nervo fibular no membro pélvico direito e fixação desde à musculatura; no membro pélvico esquerdo foi realizada a secção do nervo fibular e anastomasado término-lateral com o nervo tibial. No grupo B, os procedimentos foram idênticos aos realizados no grupo A, sendo somente invertido os membros pélvicos. No nonagésimo dia do ato operatório, foi realizada uma biópsia em cada nervo fibular para análise histológica à microscópia óptica, onde a reinervação foi objeto de estudo. A reinervação ocorreu mostrando que a integridade do epineuro não impediu a regeneração axonal.

Protein has become an increasingly valuable food component with high global demand. Consequently, unconventional sources, such as industrial and agroindustrial wastes and by-products, emerge as interesting alternatives to meet this demand, considering the UN Sustainable Development Goals and the transition to a circular economy. In this context, this work presents a review of the use of Steam Explosion (SE), a green technique that can be employed as a pretreatment for various waste materials, including bones, hide/leather, feathers, and wool, aimming the extraction of protein compounds, such as low molecular weight biopeptides, gelatin, and keratin, as well as to enhance the protein functionality of grains and meals. The SE technique and the main factors affecting the process's efficiency were detailed. Promising experimental studies are discussed, along with the mechanisms responsible for protein extraction and functionality improvement, as well as the main reported and suggested applications. In general, steam explosion favored yields in subsequent extraction processes, ranging from 27 to 95%, in addition to enhancing solubility and functional protein properties. Nonetheless, it is crucial to maintain the continuity of research on this topic to drive advancements in ensuring the safety of the extracted compounds for use in consumable products and oral ingestion., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Association of Food Scientists & Technologists (India) 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

In the cheese industry, whey, which is rich in lactose and proteins, is underutilized, causing adverse environmental impacts. The fractionation of its components, typically carried out through filtration membranes, faces operational challenges such as membrane fouling, significant protein loss during the process, and extended operating times. These challenges require attention and specific methods for optimization and to increase efficiency. A promising strategy to enhance industry efficiency and sustainability is the use of enzymatic pre-treatment with the enzyme transglutaminase (TGase). This enzyme plays a crucial role in protein modification, catalyzing covalent cross-links between lysine and glutamine residues, increasing the molecular weight of proteins, facilitating their retention on membranes, and contributing to the improvement of the quality of the final products. The aim of this study is to review the application of the enzyme TGase as a pretreatment in whey protein filtration. The scope involves assessing the enzyme's impact on whey protein properties and its relationship with process performance. It also aims to identify both the optimization of operational parameters and the enhancement of product characteristics. This study demonstrates that the application of TGase leads to improved performance in protein concentration, lactose permeation, and permeate flux rate during the filtration process. It also has the capacity to enhance protein solubility, viscosity, thermal stability, and protein gelation in whey. In this context, it is relevant for enhancing the characteristics of whey, thereby contributing to the production of higher quality final products in the food industry. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

The food industry is always looking for new strategies to extend the shelf life of food. In recent years, the focus has been on edible films and coatings. These play an essential role in the quality, safety, transport, storage, and display of a wide variety of fresh and processed foods and contribute to environmental sustainability. In this sense, this study aimed to carry out a bibliometric analysis and literature review on the production of whey-based films for application in food packaging. Whey-based films have different characteristics when compared to other biopolymers, such as antimicrobial and immunomodulatory capacity. A wide variety of compounds were found that can be incorporated into whey films, aiming to overcome their limitations related to high solubility and low mechanical properties. These compounds range from plasticizing agents, secondary biomacromolecules added to balance the polymer matrix (gelatin, starch, chitosan), and bioactive agents (essential oils, pigments extracted from plants, and other antimicrobial agents). The most cited foods as application matrix were meat (fish, chicken, ham, and beef), in addition to different types of cheese. Edible and biodegradable films have the potential to replace synthetic polymers, combining social, environmental, and economic aspects. The biggest challenge on a large scale is the stability of physical, chemical, and biological properties during application. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

Gelatin is the product resulting from collagen denaturation, which, in addition to conventional sources of extraction, can be recovered from wastes and byproducts rich in collagen widely generated by the industrial activities of poultry and cattle slaughterhouses and the fishing industry. Given the properties of good film-forming ability, nontoxicity, and biocompatibility for the addition of other compounds to obtain composite materials, gelatin is a potential polymer for the production of biodegradable films and, if extracted from waste sources, can contribute to the reduction of environmental pollution and positively impact several of the Sustainable Development Goals from the United Nations Organization. The gelatins extracted from porcine, poultry, and fish skins and untanned bovine hide wastes, or by-products can be used for the production of packaging films or edible coatings, while chromium-tanned leather wastes can be applied with mulching films in agriculture aiming at greater crop yield for food production. Also, the crosslinking of gelatin protein chains and the addition of plasticizers and other additives have shown promising results in improving gelatin films' mechanical, barrier, and solubility properties. In this sense, this paper reviewed gelatin-based films from wastes, covering the main characteristics of gelatin, techniques for film production and characterization, and applications of obtained films for the food field, in addition to considerations about social, environmental, and economic aspects., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: The technological advances in agriculture, driven by the increased demand for food attributed to population growth, have led to the search for technologies that allow greater control over the variables that interfere in crop yield. Several techniques stand out for optimizing yield capacity, including cultivation in a protected environment, mulching and low tunneling. To expand the use of these techniques, synthetic petroleum-based polymers are employed due to their low cost, easy processing, and lightness. However, they take a long time to degrade, and, since they are discarded at the end of each cycle of cultivation, end up accumulating in the environment causing irreversible damage., Results: The use of biodegradable films, made of starch and/or a protein source such as gelatin, has been studied as a promising alternative. Both stand out because of their film-forming ability, and because they come from abundant sources and are biodegradable., Conclusion: This study aimed to review the current findings on starch and gelatin films that can be used as alternatives to conventional plastics in agricultural crops. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

Purpose: To evaluate axonal regeneration after end-to-side nerve repair with fibrin glue in rats., Methods: Forty-five Wistar rats were divided into three groups: group A (n=15), were not submitted to surgery (control group); group B (n=15) were submitted to fibular transection without repair; and group C (n=15), were submitted to fibular transection with end-to-side nerve anastomosis using fibrin glue, in the lateral surface of an intact tibial nerve. The three groups were submitted to walking track (30 and 90 days) and posterior morphometrical analysis (90 days)., Results: The functional tests demonstrated that there was no difference in the walking track during the study in group A (p>0.05). The group B had walking pattern impairment in the two tests (p>0.05). The group C had walking pattern impairment in the first test, with important recovery in the second test (p<0.05). The morphometrical assessment revealed significantly higher number of regenerated mielinates axons in group C, compared to group B (p<0.05)., Conclusion: The end-to-side nerve repair with fibrin glue shows axonal recovery, demonstrated through functional and morphometrical ways in rats.