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关键词： Mammals  

摘要： Astaxanthin (AST) has been shown to have neuroprotective effects;however, its bioavailability in vivo is low due to its hydrophobic properties. In this study, lactoferrin (LF) was prepared by heat-treatment at different temperatures, and on this basis, a layer-by-layer self-assembly method was used to construct double-layer emulsions with LF as the inner layer and polysaccharide (beet pectin, BP or carboxymethyl chitosan, CMCS) as the outer layer. Then AST was encapsulated in the emulsions and their physiochemical properties and function were investigated. The results indicated that high temperature heated LF (95 degrees C) showed a more stable structure than the lower temperature one, and the exposed internal nonpolar groups of LF could give the emulsion an enhanced stability. The rheology results showed that compared with CMCS, the double-layer emulsion formed by BP had a higher viscosity. In addition, the 95 degrees C LF-AST-BP emulsion showed the best stability among all the bilayer emulsions. The best emulsion was then used as a model drug to investigate its effects on lipopolysaccharide (LPS)-induced neuroinflammation and learning-memory loss in C57BL/6J mice. Through animal behavioral experiments, it was found that dietary supplementation with the AST emulsion could effectively improve the brain cognitive and learning memory impairment caused by inflammation. Transmission electron microscopy, mRNA and western blotting results also illustrated that the AST emulsion could alleviate neuroinflammation caused by LPS. This study provides a feasible scheme for exploring an AST loaded system and may be suitable for food and drug applications.

关键词： Lithium-ion battery   Physico-chemical characterization   Parameter measurement   P2D model   Newman model  

摘要： To effectively evaluate battery performance by means of electrochemical modelling, a consistent set of parameters is essential. The aim of this work is to provide a complete physico-chemical methodology to measure all the necessary parameters for a pseudo-two-dimensional (P2D) electrochemical model. Com-ponent composition, thermodynamic, kinetic and transport properties, parameters related to the porous structures, internal battery configuration and full-cell electrode balancing are presented for a commer-cial lithium-ion battery. Then, the measured parameters are entered into the P2D model, and battery responses are evaluated against full-cell experimental curves (galvanostatic charge-discharge at different current rates, EIS responses and pulses) to correlate numerical-experimental results. ? 2021 Elsevier Ltd. All rights reserved.

关键词： Organic amendments   16S rRNA amplicon study   Soil respiration   Enzymatic activity   Carbon cycle   Soil bacterial co-occurrence patterns   Drylands  

摘要： The selection of a suitable organic amendment for recovery of semi-arid soils degraded by mining is key to the success of an ecological restoration. The aim of this research is to study the short-term responses of physicochemical, biochemical and biological properties, as well as the changes of a soil bacterial community at the genus level after application of five types of organic amendments in a limestone quarry in Almeria (SE, Spain). The relationship among bacterial taxa with biochemical and physicochemical properties and priming effect from restored soils was also analysed. Six months after the application of organic amendments, the values of different soil status, such as total organic carbon, total nitrogen, assimilable phosphorus and labile organic matter forms (carbohydrates and polyphenols), basal respiration (BR) and enzymatic activities increased significantly with respect to unrestored soils. Similarly, a positive priming effect of soil organic matter mineralisation was produced by all organic amendments, being significantly higher (p < 0.05) in sewage sludge-treated soils. Bacterial diversity was higher in restored than in control soils. The restoration caused changes in soil bacterial communities' composition at the phylum and genus levels. It was observed that soil bacterial communities were significantly related to several physical, chemical and biochemical soil properties, establishing two different co-occurrence patterns between restored and unrestored soils. A first bacterial co-occurrence pattern showed significant positive correlations to pH and C/N ratio and negativity with the rest of the soil properties. The second bacterial pattern was positively correlated with carbohydrates, mu g of C, priming effect, BR, beta-glucosidase and phosphatase and negatively with pH and C/N ratio. It was concluded that soil bacterial communities are clearly influenced by the types of organic amendments applied. Bacterial taxa such as Taibaiella or Pseudomonas c

关键词： fibers   membranes   morphology   nanoparticles   nanostructured polymers   nanowires and nanocrystals  

摘要： The incorporation of inorganic nanoparticles into polymers have gained significant attention to improving functional properties. The ultimate nanocomposite behaviors are influenced by many parameters, such as microstructural distribution that are produced during the treatment process. Herein, a hybrid material integrating a modified network into a polyimide PI matrix was produced via the sol-gel method by the reaction of pyromellitic dianhydride, 4, 4-oxydianaline, and 1, 5-diaminonaphthalene to synthesize copolyimides nanocomposite. The modified polyimide and unmodified polyimide silica (SiO2) nanoparticles were incorporated in the polyimide matrix to have polyimide silica nanocomposite. In modified silica nanoparticles, 3-aminopropyltriethosilane was introduced to have better compatibility among inorganic-organic hybrid with similar chemical contact due to their flexible alkyl group. The surface morphology or structure of silica and polyimide was affirmed by scanning electron microscopy, Fourier transforms infrared spectroscopy confirmed the synthesis of pure polyimide, unmodified polyimide, and modified polyimide silica via presence and absence of certain peaks. Thermogravimetric analysis (TGA) results showed high thermal stability of nanocomposites as silica content increases. In contrast to unmodified silica, the modified silica provides more thermal stability to the nanocomposites. Dynamic mechanical analysis was used to investigate the tensile stress of pure polyimide, unmodified, and modified silica nanocomposites. Thermal stability, storage modulus, and moisture absorption of these hybrid materials were improved with silica nanoparticles. The TG mass spectrum confirms the successful synthesis of modified silica networks. The substituted silica nanoparticles show higher mechanical toughness and storage in modified compared to unmodified silica nanocomposite, which exhibits stronger binding attraction between silica nanoparticles and polyimide matrix.

关键词： Cotton gin waste   Diethylene glycol   Glycerol   Urea   Ethyl cellulose   Sustainability  

摘要： A new cost-effective approach for producing bio-plastic from the combination of poly (vinyl alcohol) (PVA) and cotton gin trash (CGT) is reported in this study intended for probable replacement of non-biodegradable plastics in packaging. The effect of diethylene glycol, glycerol and urea as plasticisers and ethyl cellulose (EC) as coating agent were investigated. The plasticising effect was governed by the synergistic influence of the solubility parameter, molecular weight and the linearity of the plasticisers' chemical structure. A better plasticising effect reduced the vacant areas at CGT/PVA interfaces, and decreased the crystallinity and tensile strength, while improved the moisture absorption, transmission and thermal stability. Urea, as the plasticiser, showed the best performance among others (modulus 257 MPa, slightly higher than that of commercial LDPE (213.5 MPa), followed by glycerol. With complete flexibility (folding endurance >200), the tensile strength of the composite films was higher than LDPE. The film coated with EC was able to resist water drop penetration at least for 10 min. The films were semi-transparent and have excellent UV resistance. The related cost of electricity and chemicals per gram film production was estimated around 0.02 and 0.18-0.19 AUD, respectively. Overall, this study showed a sensible method of producing water-resistant flexible bio-plastic that could be beneficial in encountering current plastic pollution. (c) 2021 Elsevier Ltd. All rights reserved.

关键词： Dietary supplements   Interfaces   Peptides and proteins   Dietary fiber   Molecules  

摘要： The asymmetric water-air interface provides a dynamic aqueous environment with properties that are often very different than bulk aqueous or gaseous phases and promotes reactions that are thermodynamically, kinetically, or otherwise unfavorable in bulk water. Prebiotic chemistry faces a key challenge: water is necessary for life yet reduces the efficiency of many biomolecular synthesis reactions. This perspective considers water-air interfaces as auspicious reaction environments for abiotic synthesis. We discuss recent evidence that (1) water-air interfaces promote condensation reactions including peptide synthesis, phosphorylation, and oligomerization;(2) photochemistry at water-air interfaces may have been a significant source of prebiotic molecular complexity, given the lack of oxygen and increased availability of near-ultraviolet radiation on early Earth;and (3) water-air interfaces can promote spontaneous reduction and oxidation reactions, potentially providing protometabolic pathways. Life likely began within a relatively short time frame, and water-air interfaces offer promising environments for simultaneous and efficient biomolecule production.

关键词： Electrolyte solutions   Electrodes   Inorganic carbon compounds   Solvents   Lithium  

摘要： Fluorinated ethyl acetate with a low dielectric constant was used as a solvent to obtain highly concentrated electrolyte solutions. LiPF6 and LiBF4 were dissolved at various concentrations in fluorinated ethyl acetate, and the solution structures were studied by Raman and Fourier transform infrared spectroscopy. The nearly saturated electrolyte solutions showed unique physicochemical characteristics different from those of conventional carbonate ester-based solutions. The effects on the electrochemical properties of LiNi0.8Co0.1Mn0.1O2 (NCM811) positive electrodes were also investigated. The fluorinated ethyl acetate-based electrolyte solutions had an excellent feature of suppressing the polarization even at high concentrations of lithium salts and delivered superior charge/discharge properties.

关键词： Colloidal particles   Antioxidant activity   beta-Lactoglobulin   3,5-di-O-caffeoylquinic acid   Physicochemical properties  

摘要： Milk proteins and polyphenols are increasingly being studied as functional ingredients due to the epidemiologically-proved health benefits. In this study, composite beta-lactoglobulin (beta-lg) or beta-lactoglobulin nanoparticles (beta-lgNPs)-3,5-di-O-caffeoylquinic acid (3,5diCQA) with superior physicochemical and antioxidant activity (AA) were produced using beta-lg and 3,5-di-O-caffeoylquinic acid. The main interactions between beta-lg or beta-lgNPs with 3,5diCQA were hydrogen bonding and hydrophobic effects. The 3,5diCQA caused a decrease in a-helix and beta-sheet structure with a corresponding increase in unordered structure. Compared to beta-lg alone, composite beta-lg or beta-lgNPs-3,5diCQA slightly decreased the particle size but increased their negative surface potentials especially for beta-lg or beta-lgNPs at a molar ratio of 5:1. The addition of 3,5diCQA appreciably improved the AA in a dose-dependent manner. These results shed light on the structural, physicochemical, and AA of composite beta-lg or beta-lgNPs-3,5diCQA non-covalent complexes, important for application as functional ingredients in food solutions as well as in the pharmaceutical industry.

关键词： Methylene blue (MB)   Metal-organic frameworks (MOFs)   Zeolitic imidazole framework (ZIFs)   Box-Behnken design (BBD)   Modeling   Parametric optimization  

摘要： Adsorption of methylene blue (MB) was explored using different metal-organic frameworks (MOFs) and zeolitic imidazole framework (ZIFs) to optimize the physicochemical parameters by parametric modeling and to study the kinetics and equilibrium of the adsorption process. The frameworks were synthesized using three different metals (Fe, Zn, Co) and two linkers (2-Methylimidazole, terephthalic acid). Based on screening analysis, ZIF-8 (Zn) with a cubic morphology exhibited the highest adsorption capacity of 43.1 mg g(-1) toward MB. The adsorption capacities of the rest studied MOFs were 25.0 mg g(-1) for MIL-53 (Fe), 22.7 mg g(-1) for MIL-88B (Fe), 18.4 mg g(-1) for Ni-MOF, 16.8 mg g(-1) for ZIF-67, and 15.5 mg g(-1) for MIL-101 (Fe). The effect of contact time, initial solution pH, the dosage of the utilized framework, and MB initial concentration and their bimodal interactions on dye removal were elucidated by modeling the process according to Box-Behnken design (BBD). The model explained an incremental MB removal by pH, contact time, and adsorbent mass and inversely by dye concentration. Parametric optimization of the model revealed that the highest dye removal was achieved at a contact time of 53.4 min, MOF dose of 0.68 g L-1, pH=8.5, and an MB initial concentration of 25mg L-1. Nonlinear Khan isotherm and Pseudo-first-order and Pseudo-second-order kinetic models described better MB removal. These findings revealed that the adsorption could be described as a monolayer phenomenon under low dye concentrations values, e.g., 25 mg L-1, while it switches to multilayer at higher MB concentrations around 100 mg L-1. (C) 2021 Elsevier B.V. All rights reserved.

关键词： D-glucans   Physicochemical properties   Prebiotic effect  

摘要： Mushroom D-glucans are recognized as dietary fibers and as biologically active natural polysaccharides, with the advantages of being quite inexpensive for production, tolerable, and having a range of possible structures and physicochemical properties. The prebiotic potential of mushroom D-glucans has been explored in recent years, but the relationship between their various structural features and activity is poorly understood. This review focuses on comprehensively evaluating the prebiotic potential of mushroom D-glucans in face of their structural variations. Overall, mushroom D-glucans provide a unique set of different structures and physicochemical properties with prebiotic potential, where linkage type and solubility degree seem to be associated with prebiotic activity outcomes. The understanding of the effects of distinct structures and physicochemical properties in mushroom D-glucans on the gut microbiota contributes to the design and selection of new prebiotics in a more predictable way.