Search Results (1,099)

Quercetin (QE), a flavonol-type polyphenol, and oat β-glucan (OβG), a soluble dietary fiber, are natural active ingredients with the potential to reduce the risk of diabetes. OβG slows starch digestion by modifying chyme viscosity, while QE inhibits digestive enzyme activity. This study aimed to explore the formation mechanism and structural characteristics of QE-OβG complexes, as well as their functional properties in terms of viscosity and amylase inhibitory activities. It was found that QE and OβG formed stable non-covalent complexes via hydrogen bonding and hydrophobic interactions. At a mass ratio of 0.6, the binding capacity was relatively high with a moderate aggregation degree, representing a balanced interaction state. Changes in turbidity and particle size indicated that different environmental factors (pH, temperature, ionic strength) exert differential effects on the aggregation behavior of the complex. In addition, the complex exhibited a unique fibrous-block morphology, enhanced thermal stability, improved starch system viscoelasticity, and stronger mixed-type reversible α-amylase inhibition (IC₅₀ = 2.629 mg/mL). This study clarifies the interaction mechanism between QE and OβG, provides a reliable theoretical basis for the development of novel hypoglycemic foods, and offers new insights into multi-component regulation strategies for slow-digestion food design. Full article

Mercury pollution from artisanal and small-scale gold mining remains one of the most persistent environmental threats due to the high toxicity, mobility, and bioaccumulation of Hg(II). In this work, Colombian banana pseudostem waste is valorized into a lignocellulosic carbocatalyst through pyrolysis at 500 °C followed by MnCO₃-derived MnOx functionalization, producing a sustainable material for Hg(II) remediation. The transformation of the biomass leads from a fibrous structure (~25 µm) to a pyrolyzed carbon matrix (9.56 µm), and finally to a heterogeneous Mn-modified system with bimodal particle distribution (~25 µm and ~0.85 µm), the latter being associated with highly dispersed MnOx redox-active domains. Structural and textural analyses reveal that Mn incorporation significantly enhances surface properties, increasing the BET surface area from 140.8 to 213 m² g⁻¹ while reducing pore size to the meso–microporous range (~1.9 nm). Importantly, the material retains intrinsic minerals such as Ca, Mg, K, and Si, which contribute to surface basicity and ion-exchange capacity, supporting additional Hg(II) interaction pathways. Optical and electronic characterization shows a wide band gap semiconductor behavior (≈3.4 eV) and a conduction band position at −0.892 V vs. NHE, sufficiently negative to thermodynamically drive Hg²⁺ reduction to Hg⁰ under UV-A irradiation. Hg(II) quantification was validated using a UV–Vis method based on the Hg²⁺–dipicolinic acid (DPA) complex, confirming stable complex formation with 1:2 stoichiometry (Hg²⁺:DPA) and high analytical reliability (R² = 0.948, LOD = 1.85 mg L⁻¹). Photocatalytic experiments demonstrated negligible Hg(II) reduction under UV-A light in the absence of catalyst, whereas the carbon-based materials enabled significant Hg transformation through adsorption-assisted photoinduced electron transfer. Electrochemical analyses (Rct ≈ 11 Ω) confirmed efficient charge transport, while cyclic voltammetry evidenced reversible Mn(IV)/Mn(III)/Mn(II) redox cycling, which sustains electron mediation during photocatalysis. Overall, pristine biochar acts primarily through adsorption driven by oxygenated functional groups and porous structure, whereas Mn-functionalized biochar operates via a synergistic adsorption–photocatalytic mechanism. In this system, MnOx species function as redox-active centers that facilitate electron transfer from the carbon matrix to Hg(II), while the conductive lignocellulosic-derived framework enhances charge mobility. The combination of structural carbon stability, dispersed Mn active sites, and inherent mineral functionality establishes a highly efficient and sustainable carbocatalyst, demonstrating a green and scalable approach for mercury remediation in mining-impacted regions. Full article

Bone grafting remains limited, and the strategies to design even more structurally complex scaffolds—able to reproduce the hierarchical architecture of bone extracellular matrix—are rapidly growing. In this study, we report the fabrication of a hierarchically structured scaffold produced by layering poly(ε-caprolactone)/gelatin (PCL/Gt) or poly(lactic acid)/gelatin (PLA/Gt) electrospun nanofibers via coaxial electrospinning onto 3D-printed poly(lactic acid) (PLA) scaffolds via fused deposition modeling (FDM). After the printing process, PLA disks (10 × 1 mm, 20% infill, ~80% porosity, pore size ~1.57 mm) were coated with core/shell (PCL/Gt, PLA/Gt) fibers to investigate the in vitro interfacial response of osteoblasts in comparison with monocomponent fibrous coatings (PCL, PLA, Gt). SEM and TEM confirmed that core/shell fibers exhibited bead-free morphologies, with a significant reduction in fiber diameter (≈287–316 nm) and higher interfibrillar porosity compared to monocomponent fibers. FTIR and thermogravimetric analyses indicated the presence of hydrogen bonding between the polyester and gelatin, and the absence of residual solvent after deposition. At the same time, water contact angle measurements confirmed an increase in hydrophilic properties from 80–86° to 120° ascribable to the presence of gelatin. Accordingly, in vitro response of human fetal osteoblasts (hFOB 1.19) exhibited an evident improvement in the case of Gt-based fibrous coatings (i.e., PCL/Gt and PLA/Gt) in terms of early adhesion (4–24 h) and metabolic activity from 3 to 21 days, cell spreading into star-shaped morphologies, formation of extracellular matrix, and mineral phase deposition. In more detail, a remarkable increase in alkaline phosphatase activity was observed in Gt-based coaxial coatings from day 7 onward, with the highest values recorded for PLA/Gt. Overall, we demonstrated that the Gt-based coaxial fibrous coating provided a mix of topological and biochemical cues that synergistically promoted key osteoblast activities at the interface, supporting the regeneration of new bone tissue in highly tailored 3D-printed scaffolds, thus suggesting a promising strategy for personalized regenerative medicine. Full article

Persistent uncertainty in translating low-field nuclear magnetic resonance (NMR) T₂ relaxation spectra into geometrically meaningful pore–throat metrics has long hindered the quantitative characterization of tight reservoirs. To address this issue, this study develops an enhanced conversion framework that incorporates scale-dependent pore geometry, enabling more realistic estimation of pore–throat radius distributions. Core samples were collected from the first member of the Shanxi Formation and the eighth member of the Shihezi Formation in the Ordos Basin. A comprehensive experimental dataset was established, including porosity and permeability measurements, X-ray diffraction (XRD) mineral analysis, NMR experiments, high-pressure mercury intrusion (HPMI), and constant-rate mercury injection (CRMI). The results demonstrate that total clay content exhibits weak correlations with pore size and porosity. In contrast, the occurrence and morphology of specific clay minerals exert significant control on pore connectivity and flow behavior. In particular, fibrous illite increases pore–throat complexity, while early chlorite coatings help preserve primary intergranular pores. A single geometric model cannot fully represent the complex pore–throat system in tight sandstones. For pores, a spherical geometry is most appropriate and indeed necessary. Smaller throats connecting these pores often exhibit geometries more consistent with cylindrical shapes. Within the coarse pore size range, large pores dominate the reservoir space and generally exhibit geometries that better conform to a spherical shape. And larger pores dominate the volumetric contribution in the coarse pore-size range. These observations suggest that a scale-dependent composite model could further improve the accuracy of NMR-based pore-size estimations. Therefore, the spherical-pore model provides a physically meaningful framework for characterizing pore structures in tight reservoirs. At the same time, incorporating scale-dependent considerations offers a promising avenue for future methodological development. Full article

This study investigates the mechanical, structural, and thermal performance of bio-based composite laminates reinforced with nonwoven fibrous materials derived from polylactic acid (PLA), poly(butylene succinate) (PBS), and polyamide 1010 (PA1010). The fibrous reinforcements, produced using melt-blown and electrospinning techniques, were characterized in terms of morphology, fibre diameter distribution, and wettability, and subsequently incorporated into bio-resin laminates to strengthen them. The curing behaviour of the composites was evaluated using differential scanning calorimetry (DSC). The results demonstrate that fibre structure and morphology strongly influence resin impregnation and interfacial interactions. Mechanical properties varied significantly depending on the reinforcement type. PA1010-based laminates exhibited the highest strength and stiffness due to their compact and uniform fibrous structure. PBS-based systems showed intermediate behaviour, while PLA-based composites displayed lower strength but higher deformability. DSC results indicated that fibre type affected crosslinking efficiency. Thermogravimetric analysis (TGA) revealed similar initial thermal stability of laminates (T₅% ≈ 299–313 °C), governed by the resin matrix, while differences at higher temperatures reflected the type of reinforcement used. These findings highlight the importance of fibre morphology and interfacial compatibility in designing sustainable composite laminates reinforced with recycled fibrous materials. Full article

The textile industry has contributed significantly to global microplastic pollution, generating both primary and secondary microplastics. Primary microplastics, released during the manufacturing process of textiles, are the main concern due to their long-chain structure and persistence, while secondary microplastics are generated from the degradation of synthetic or blended textile products, which have already been in service or use. This review provides a comprehensive overview of methods for investigating fibrous primary microplastics generated throughout the major stages of the textile value chain, including yarn production, fabric manufacturing, garment processing, finishing, and packaging. In fact, there is an urgent need to deal with fibrous primary microplastics, as they are particularly hazardous due to their form (thin, long and often needle-like) and long-lasting life (can sustain in the environment over hundreds of years). Each manufacturing stage produces measurable microfiber losses. For example, pre-consumer production emits approximately 0.12 million metric tons of microplastics per year. High-speed yarn spinning releases additional MP (microplastics); rotor-spun polyester yarns shed 2000–8000 MFPs/g (microplastic fibers/g). The mechanical stresses such as friction, abrasion, and yarn breakage during weaving and knitting operations contribute significantly up to 10⁴–10⁶ microfibers per m² of fabric during production. Wet processing (dyeing, printing, and finishing) is another major hotspot for primary microplastic generation, with dye house effluents reporting up to 54,100 microfibers per liter. Moreover, during mechanical and chemical finishing operations, the generated nanoplastics (NPs) rose significantly, exceeding 10¹¹ particles per gram of material. Subsequently, the garments manufacturing units are estimated to produce 10,000 garments per day (5 tons of fabric), which equates to 5–25 kg/day of microplastic fiber waste. Targeted schemes for the study of primary microplastics at the earliest stages of textile production could significantly reduce environmental release and strengthen progress toward a more circular and sustainable textile economy. Full article

The NiO/Al₂O₃-CaO, CuO/Al₂O₃-CaO and CoO/Al₂O₃-CaO catalytic systems were investigated for the decomposition of ozone. Each of the three different Al₂O₃-CaO carriers was obtained after treatment of the initial precursor at 1100 °C for 2, 4 and 6 h, respectively, to examine the effect of annealing on support calcination. AAS, XRD, XPS, EPR, SEM and BET were applied for sample characterization. The carrier comprises a mixture of corundum α-Al₂O₃, θ-Al₂O₃ and Ca₃Al₂O₃. The XRD spectra of the active phases of the catalysts show the existence of Co₃O₄, NiO, Ni₂O₃ and CuO. The SEM micrographs reveal spherical particles for the NiO/Al₂O₃–CaO sample. In contrast, the CoO/Al₂O₃–CaO sample exhibits a morphology composed of wool-like fibers and perpendicularly oriented plate-like structures. The CuO/Al₂O₃–CaO sample consists not only of fibrous structures but also of distinct, separated aggregates. The obtained catalysts have highly developed specific surface areas. Their catalytic activity depends on the calcination conditions of the support, and the best results are observed after 2h treatment for all of the investigated samples due to the smaller crystallite size and higher specific surface area. The activity of the investigated catalysts for the ozone decomposition reaction follows the order NiO/Al₂O₃-CaO > CoO/Al₂O₃-CaO > CuO/Al₂O₃-CaO. Full article

Panax vietnamensis Ha et Grushv. (Vietnamese ginseng) is a plant of the Panax genus, Araliaceae family. It is a rare medicinal plant found in China and Vietnam, known for its structurally diverse ginsenosides, and holds significant value in the pharmaceutical and health food sectors. As market demand and its value continue to rise, the P. vietnamensis industry has developed rapidly. However, since Vietnamese ginseng is difficult to distinguish from other Panax materials based on appearance, especially Panax notoginseng, there is a lack of relevant standards for quality control. In this study, UPLC-Q/TOF-MS technology was employed for the qualitative identification and comparative analysis of ginsenosides in different parts of P. vietnamensis and three other Panax species. Additionally, an UFLC-MS/MS method was established to determine the content of 21 ginsenosides in P. vietnamensis. Based on the UPLC-Q/TOF-MS analysis, 55 ginsenosides were preliminarily identified, including 30 protopanaxadiol-type, 21 protopanaxatriol-type, 3 ocotillol-type, and 1 oleanane-type ginsenosides. Further comparative analysis revealed variations in the ginsenosides of P. vietnamensis and three Panax species, identifying 41 components present in all species, while 14 saponins were detected only in some species. Compared to three Panax species, the main roots of P. vietnamensis contained characteristic components such as majonoside R₂, majonoside R₁, and vinaginsenoside R₂. Quantitative analysis of 21 ginsenosides in different Panax species indicated that P. vietnamensis and P. notoginseng contained higher levels of ginsenoside Rg₁, Rd, Rb₁, and notoginsenoside R₁. For instance, the average content of ginsenoside Rg₁ in P. vietnamensis was 25.57 mg/g. Quantitative analysis of ginsenosides in different parts of P. vietnamensis revealed that the taproots and fibrous roots had a diverse array of ginsenosides with higher concentrations, while the stems and leaves contained fewer ginsenosides with lower levels. Significantly, certain components such as notoginsenoside Re and ginsenoside Rd, Re, and Rb2 were present at higher concentrations in the leaves. Based on the qualitative and quantitative analysis results of ginsenosides from different parts of P. vietnamensis, it was concluded that the main roots, fibrous roots, and leaves all have potential for development and utilization. Full article

A conformal SiNx coating on carbon nanotubes (CNTs) was achieved by combining transient UV–ozone surface functionalization with a two-step atomic layer deposition (ALD) process. UV–ozone treatment gradually increased the defect density of CNTs, with the I_D/I_G ratio increasing from 0.05 for pristine CNTs to 0.25 after 7 min of exposure, while the overall fibrous CNT network remained intact. However, prolonged UV–ozone exposure beyond 10 min led to a sharp increase in the I_D/I_G ratio to 0.46, accompanied by structural degradation of the CNT membrane. Hydroxyl (-OH), epoxy (C-O-C), and carbonyl (C=O) groups were introduced by UV–ozone treatment and were partially removed during subsequent high-temperature processing. Accordingly, direct high-temperature ALD resulted in incomplete SiNx coverage of the CNTs, suggesting insufficient nucleation. A two-step ALD process, consisting of several cycles of low-temperature nucleation at 100 °C followed by high-temperature growth at 700 °C, enabled more conformal deposition of SiNx on CNTs. In addition, both annealing and ALD reduced the defect level toward that of pristine CNTs, supporting the transient nature of UV–ozone-induced functionalization. Full article

Background/Objectives: The composition of atherosclerotic plaques is increasingly recognized as a key factor determining cardiovascular risk. Features such as intraplaque hemorrhage, a necrotic lipid core, and the integrity of the fibrous cap are strongly associated with plaque instability and the occurrence of adverse clinical events. Magnetic resonance imaging (MRI) allows for non-invasive characterization of plaque microstructure through quantitative mapping of T1 and T2 relaxation times; however, image noise may limit the accuracy of these measurements. Methods: In this experimental study, a total of 15 ex vivo atherosclerotic plaque samples were imaged using a 1.5T scanner with a fast spin-echo sequence featuring variable repetition times (TR: 200–12,000 ms) and echo times (TE: 21–240 ms) to obtain T1 and T2 maps. An Attention–Residual–Dense U-Net neural network was trained on pairs of noisy and reference images to reduce Rician noise while preserving structural details. Results: The 15 samples examined exhibited T1 values ranging from 1768 to 3294 ms and T2 values ranging from 138 to 202 ms, which were shorter than those for water (T1: 3323 ms; T2: 114 ms), which is consistent with the presence of collagen, lipids, and mineral deposits. Variability among samples reflected differences in composition, with the shortest relaxation times suggesting advanced calcifications. The application of deep learning methods allowed for a threefold improvement in the signal-to-noise ratio (SNR) while preserving the microarchitecture of the lamina. Conclusions: Quantitative T1/T2 mapping combined with deep learning-based image enhancement methods constitutes a robust tool for high-resolution characterization of atherosclerotic plaque composition under ex vivo conditions. The results obtained indicate the potential for translating this method to in vivo studies to better detect tissue heterogeneity and features associated with plaque instability. Full article

Introduction. The superficial musculoaponeurotic system (SMAS) is fundamental for facial soft tissue support and surgical rejuvenation. Although its morphology in the midface and neck is well characterized, the structure of its cranial extension to the forehead remains a subject of terminological uncertainty. The aim of this study was to conduct a detailed histological and immunohistochemical examination of the forehead supporting structures to characterize their morphology and propose an expanded, region-specific classification of the SMAS. Material and methods. Full-thickness tissue specimens (n = 30) were obtained from five standardized facial regions (parotid, buccal, temporal, frontal, and cervical) from 12 male and 18 female body donors (aged 25–70 years). Specimens were processed for histological analysis using hematoxylin and eosin, van Gieson staining, and Masson’s trichrome. Immunohistochemical staining for S100 protein was used to identify neural structures. Morphometric analysis was performed on digitized sections to quantify interseptal distances and the depth of superficial nerve trunks. Results. The analysis confirmed the established SMAS types (I–V) in the cheek, parotid gland, and neck, confirming the validity of the method. Two distinct, sequentially arranged structures were identified on the forehead, proposed as new types. Type VI (neurovascular arborization) is a discrete fan-shaped structures with a central collagen core surrounding a neurovascular bundle, showing positive S100 staining. These structures, spaced approximately 2.2 mm apart, function as true retaining ligaments. Type VII (fibroseptal) SMAS patterns is vertically oriented, purely fibrous septa (retinacula cutis) connecting the aponeurosis to the dermis, devoid of neural elements, and spaced approximately 9.2 mm apart. Importantly, the superficial nerve trunks were located at an average depth of only 1.09 mm (range: 0.57–1.97 mm) from the skin surface. Conclusion. This study identified two novel SMAS patterns in the forehead—neurovascular arborization (type VI) and fibroseptal (type VII)—supporting the expanded functional seven-type classification of the SMAS. The extremely superficial location of the forehead nerves (average 1.1 mm) defines a critical “danger zone” for aesthetic procedures. These findings provide a refined anatomical basis for improving the precision and safety of both surgical and minimally invasive facial procedures. Full article

The production of cultivated meat relies on in vitro animal cell growth and requires the use of scaffolds that structurally resemble key features of the extracellular matrix (ECM), providing mechanical support and biochemical cues for cell adhesion, proliferation, and differentiation. Electrospinning has emerged as a promising technique for manufacturing three-dimensional edible scaffolds because it is robust, versatile, and capable of producing nanofibers with a high surface area-to-volume ratio, tunable porosity, and ECM-like fibrous architectures. Natural biopolymers are promising candidates for the fabrication of electrospun scaffolds, combining biocompatibility, biodegradability, and processing compatibility with food-grade requirements. However, the absence of fully food-grade electrospinning systems, coupled with limited scalable green-processing strategies, remains a critical barrier to industrial translation. In this context, this review presents recent advances in the food-grade electrospinning of natural biopolymers focused on cultivated meat production. Furthermore, scientific gaps in the development of fully edible scaffolds are discussed, along with the need for alternatives to animal-derived materials and synthetic carrier polymers, considering sustainability, consumer acceptance, and the translation from laboratory-scale studies to industrial systems. Finally, this review outlines a strategic roadmap to accelerate the transition from proof-of-concept studies toward scalable, regulatory-compliant, and industrially viable electrospinning technologies for cultivated meat production. Full article

Water contamination resulting from anthropogenic activities poses a critical threat to ecosystems and human health. The development of efficient, sustainable, and selective materials for water purification has therefore become a pressing necessity. In this study, polyurethanes (PUs) with tailored soft and hard segments were synthesized and characterized to evaluate their suitability for the fabrication of electrospun membranes. ATR-FTIR confirmed successful polymerization, while thermal analyses revealed that molecular design strongly influences the polymers’ thermal behavior. Among the synthesized materials, only two PUs exhibited solubility and spinnability, leading to homogeneous nanofibrous mats with average fiber diameters of approximately 500 nm. To enhance the adsorption capacity, specific surface area and interaction diversity of the membranes, metal–organic framework (MOF) particles were incorporated into the polymer solutions prior to electrospinning, allowing their immobilization within the fibrous polymer matrix. The resulting hybrid membranes showed remarkable improvements in methylene blue uptake, increasing from 29 to 34 mg·m⁻² in pristine membranes and 57 to 115 mg·m⁻² in the MOF-containing ones. This enhancement was attributed to the synergistic effect between the aromatic urethane structures and the MOF linkers, as well as to the increased effective surface area provided by the nanofibrous architecture. The results demonstrate the potential of electrospun PU-based membranes as pollutant removal, combining structural versatility, functional tunability, and compatibility. Full article

Certain clayey soils are susceptible to swelling and shrinkage due to moisture variations, which can lead to ground deformation and structural damage. Although traditional stabilization methods using lime and cement are effective, they involve high energy consumption and significant CO₂ emissions. In response to sustainability concerns, this study investigates the potential of in situ geopolymer stabilization of clay soils using industrial by-products as eco-friendly binders. Experimental studies were conducted on clay specimens stabilized with geopolymer binders produced from fly ash and waste brick powder activated by alkaline solutions. The selected clay exhibited stiff to very stiff behavior and was used as a reference material to ensure reliable evaluation without the influence of severe initial degradation. Reference samples with identical water content but without alkaline activation were also prepared. The primary objective was to assess geopolymers as a sustainable alternative to conventional binders, focusing on moisture sensitivity and long-term mechanical performance. Laboratory strength tests demonstrated that geopolymer-treated specimens exhibited significantly higher strength compared to untreated samples, indicating substantial improvement in engineering properties. Furthermore, Scanning Electron Microscopy (SEM) analyses revealed that the combination of dual activators (NS+NH) and thermal curing at 85 °C transformed the weak clay matrix into a dense, fibrous geopolymer network. However, the high curing temperature was primarily used to study the reaction mechanisms; the practical applicability of the method should be evaluated based on results obtained at ambient temperature. This structure enhanced particle bonding and mechanical interlocking by filling voids within the matrix. Overall, the findings confirm that geopolymer stabilization using industrial waste materials is an effective and environmentally sustainable alternative to conventional soil stabilization techniques, contributing to reduced carbon emissions in geotechnical engineering. Full article

In this study, electrospun poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) biopapers were produced by annealing electrospun fiber mats from two commercial grades (151C and X131A) and compared with films prepared by the conventional melt-mixing/compression molding method. To obtain continuous biopapers, the fiber mats were subjected to mild thermal post-processing at various temperatures. The selected annealing temperatures were 140 °C (151C) and 130 °C (X131A), where interfiber coalescence occurred within a short annealing time (10 s), yielding continuous fibrous films (biopapers). To elucidate the structural mechanisms underlying interfiber coalescence, time-resolved synchrotron SAXS/WAXS and temperature-dependent FTIR spectroscopy were performed. These analyses showed that coalescence occurred through an interplay between thermally induced local ordering at sub-melting temperatures and premelting/partial melting of thin, ill-defined lamellae, with grade-dependent contributions. The resulting biopapers were evaluated against compression-molded films for optical, mechanical, and barrier properties relevant to packaging. All samples showed similar transparency, although compression-molded films were slightly more opaque. The lower-rigidity grade (151C) exhibited more ductile and tougher behavior than X131A. Biopapers showed slightly lower water and oxygen barrier performance than compression-molded films, attributed to differences in material compactness. Overall, brief mild annealing after electrospinning enabled continuous PHBH biopapers with balanced properties, supporting their potential for sustainable PHBH-based food-packaging applications. Full article