Search Results (12,550)

This study investigated the self-healing behavior of Engineered Cementitious Composites (ECCs), with a focus on the influence of fiber content. ECC mixtures have shown a distinctive response under tensile loading, particularly their high tensile strain capacity, which leads to the formation of microcracks and the redistribution of stress. Three-point bending tests (at 80–90% of the maximum load) were performed to induce controlled cracking in beam specimens, followed by weekly wet–dry curing. Crack closure was monitored at the specimen surface using microscopic image acquisition and within the specimens by means of ultrasonic monitoring. The results indicated that higher fiber dosage generally promoted microcracking and reduced crack widths, thereby creating favorable conditions for self-healing. Specimens with crack widths not exceeding 0.10 mm exhibited complete or nearly complete crack closure after approximately 60 days of weekly wet–dry curing, whereas specimens with wider cracks showed only partial healing. These findings highlight the beneficial role of fibers in controlling crack development, limiting crack widths, and providing favorable sites for the formation of apparent healing products, thereby enhancing the self-healing capacity of ECCs. Full article

This study investigates the influence of controlled fiber orientation on the mechanical and microstructural properties of cellulose excelsior fiber cementitious composites with an excelsior content of 75% by volume. Two different sets of composites were fabricated. In one set, no effort was made to orient the fibers, while in the other set fibers were preferentially aligned through manual placement and compressive consolidation. The mechanical performance, including elastic modulus and flexural strength, was evaluated. The internal structure, specifically porosity and 3D fiber orientation, was quantified using X-ray Computed Tomography (XCT) and subsequent 3D image analysis. The results demonstrate that the composites with aligned fibers exhibited a 20% higher bulk density and a significantly lower porosity (5.1%) compared to the non-aligned composites (9.0%), representing a 43% reduction in void volume. Further image analysis showed distinct differences in fiber orientation relative to the axis of the specimen. These different distributions led to a 120% increase in elastic modulus and a 58% increase in flexural strength. These results demonstrate how, within limits, the mechanical properties of the composite system can be controlled to meet application demands. Full article

Ornamental palm pruning residues represent a locally abundant, underutilized lignocellulosic waste stream with potential as a waste-valorized epoxy reinforcement. This study investigates the flexural behavior of particulate epoxy composites reinforced with Washingtonia robusta leaf stalk residue, evaluating the influence of reinforcement granulometry on mechanical and microstructural response. Four specimen families were fabricated from a Bisphenol A/F epoxy resin cured with a cycloaliphatic amine hardener: neat resin (RS, reference) and composites reinforced with fine (RF), coarse (RG) and mixed-fraction (RM) particles at 20 vol.% loading. Flexural properties were assessed by three-point bending and fracture surfaces were characterized by SEM. The neat resin exhibited a non-monotonic, viscoelastic-dominated response with no fracture within the extended deformation range tested, whereas all reinforced systems fractured within a substantially narrower window (~8–14.5 mm). RF showed the highest observed flexural modulus (≈15.8 GPa), followed by RM (≈15.4 GPa) and RG (≈14.2 GPa). These differences were not statistically significant (one-way ANOVA, p > 0.05). Damage tolerance followed a similar descriptive trend: RG failed earliest, linked to large interfacial pull-out cavities; RF delayed fracture through crack deflection; and RM showed the most favorable overall balance, combining a modulus comparable to RF with superior crack path tortuosity. These results indicate the potential of Washingtonia robusta, particularly in mixed-granulometry form, as a candidate reinforcement for semi-structural epoxy biocomposites, pending further characterization of properties such as tensile strength, impact resistance, moisture absorption, and long-term durability. Full article

AZ91D is a lightweight, representative commercial magnesium alloy known for its excellent castability and specific strength. However, the mechanical properties of as-cast AZ91D remain limited by inherent brittleness, relatively low strength, and microstructural inhomogeneity caused by enrichment of secondary phases at grain boundaries. In this study, AZ91D/Csf (short carbon fiber at 0, 2.5, and 5 wt.%) composites were prepared by gravity casting with mechanical stirring, followed by post-casting T4 heat treatment and equal-channel angular pressing (ECAP). Material characterization included optical microscopy (OM), field-emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), uniaxial tensile testing, and microhardness tests. The results demonstrate that T4 treatment reduced intermetallic β-Mg₁₇Al₁₂ segregation and homogenized the microstructure, whereas one-pass ECAP further refined the grains. Mechanically, these two processes enable the (AZ91D/5 wt.% Csf) composite to achieve higher ultimate tensile strength (280.7 MPa by T4/280.2 MPa by T4 + one-pass ECAP), larger maximum strain (12.1% by T4/5.4% by T4 + one-pass ECAP), and higher microhardness (63.9 HV by T4/78.1 HV by T4 + one-pass ECAP). Compared to as-cast AZ91D, these findings demonstrate that T4 treatment provides a better strength–ductility balance via solid solution, whereas one-pass ECAP preferentially enhances surface microhardness by plastic deformation. This study highlights the performance of AZ91D/Csf composites and their potential for lightweight, high-strength-demand applications. Full article

The rapid expansion of fiber-reinforced polymers (FRPs) in wind energy, transportation, and aerospace is generating increasing amounts of accompanied waste, making effective valorization essential to a circular economy. This review compares FRP recovery technologies in terms of recovered-fiber quality, operating conditions, post-treatment, environmental impacts, and industrial applicability. Then, it also examines direct reuse, FRP remanufacturing, and reuse in cementitious composites. Quantitative synthesis indicates that high-quality recycled carbon fibers (rCFs) generally retain more than 90% of their original strength, whereas mechanically recovered glass fibers (rGFs) typically retain approximately 70–90%. The preferred pathway depends on the intrinsic value, damage state, morphology, and residual properties. Components with sufficient residual capacity should be directly reused; high-quality fibers are better suited to polymer remanufacturing; and heterogeneous or lower-grade glass-FRP (GFRP) fractions are more compatible with cementitious applications, where mechanically recycled GFRP can provide interfacial bond strengths comparable to conventional engineering macrofibers. Future research should establish quantitative links among recovered material quality, processing, interfacial behavior, and end-use performance, while adopting consistent environmental and economic assessment boundaries. A graded utilization framework is therefore required to support both large-scale and value-added reuse of FRP waste. Full article

Out-of-autoclave (OoA) manufacturing of Fiber Metal Laminates (FMLs) remains challenging because their mechanical performance and failure mechanisms are sensitive to processing-induced variations in phase distribution and interfacial bonding quality. Three FML-2/1 configurations (FML/Al-20, FML/Al-40, and FML/Al-60), where the numerical values indicate the exposure time (minutes) of 3003-H14 aluminum to NaOH alkaline etching, were physically characterized after bonding to a basalt fiber-reinforced polymer (BFRP) core to quantify constituent and void volumetric fractions. Based on previously reported differences in interlaminar strength, FML/Al-40 was selected to evaluate tensile behavior at room temperature and high temperature. The average density across all FML configurations was about 2.15 g/cm³, corresponding to a 21% reduction relative to aluminum. Compositional analysis revealed significant differences among configurations in both the complete FML and the renormalized matrix–fiber–void composition of the BFRP core, indicating that surface treatment is associated with changes in internal phase distribution beyond the metallic contribution. At room temperature, FML/Al-40 exhibited an ultimate tensile strength of 262.7 MPa. Relative to this value, tensile strength was retained at 83%, 54%, and 31% at 100, 150, and 200 °C, respectively, demonstrating a progressive reduction in strength with increasing temperature and a corresponding change in the thermomechanical response associated with evolving failure mechanisms. Full article

Background/Objectives: Obesity is a chronic, progressive, and relapsing disease that requires long-term, multidisciplinary management rather than episodic weight-loss treatment. Although novel incretin-based anti-obesity pharmacotherapies, including GLP-1 receptor agonists and dual GIP/GLP-1 receptor agonists, have markedly improved the clinical management of obesity, weight reduction alone does not fully capture treatment success. Body composition, lean mass preservation, physical function, nutritional adequacy, psychological well-being, adherence, and long-term weight-loss maintenance are increasingly recognized as essential therapeutic outcomes. This narrative review critically examines the role of lifestyle medicine as a co-therapeutic strategy during modern anti-obesity pharmacotherapy, with particular attention to physical activity, nutrition, behavioral support, and individualized monitoring. Methods: A narrative literature search was conducted in PubMed up to June 2026. The review included studies addressing adults with overweight or obesity and evidence related to anti-obesity pharmacotherapy, physical activity, nutrition, body composition, functional outcomes, eating behavior, quality of life, treatment tolerability, adherence, weight regain, and long-term maintenance. Results: Current evidence indicates that incretin-based therapies produce substantial and clinically meaningful weight loss, but pharmacological efficacy may be limited by reductions in lean mass, gastrointestinal adverse events, inadequate nutritional intake, treatment discontinuation, and weight regain after drug withdrawal. Physical activity should be considered a therapeutic component rather than only a tool for increasing energy expenditure, as aerobic exercise supports cardiometabolic health and cardiorespiratory fitness, while resistance training helps preserve muscle strength, bone health, and functional capacity. Nutritional strategies are equally important, particularly during appetite suppression, to maintain adequate protein, fiber, fluids, micronutrients, and diet quality. Behavioral factors, including sleep, stress, mood, stigma, self-regulation, and the food environment, may influence adherence and long-term outcomes. Conclusions: Novel anti-obesity drugs should not be viewed as replacements for lifestyle medicine but as powerful tools within an integrated chronic-care model. The goal of treatment should move beyond maximal body-weight reduction to durable improvements in body composition, metabolic health, physical function, nutritional status, quality of life, and weight-loss maintenance. Full article

This study develops an integrated Analytic Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) multi-criteria decision-making (MCDM) framework to systematically evaluate and rank composite material combinations based on 24 fibers (16 natural and 8 synthetic), 15 matrices (thermosets, thermoplastics, and biopolymers), and 9 fiber volume fractions (30–70%) for UAV inlet applications. Ten evaluation criteria covering technical performance, environmental sustainability, and economic viability were weighted using AHP pairwise comparisons based on Saaty’s 1–9 scale, yielding a consistency ratio of CR = 0.009, which confirms the reliability of the judgments. The TOPSIS analysis identified Carbon (PAN-HM)/Epoxy as the optimal composite material, achieving the highest TOPSIS score of 0.8893. In contrast, Flax/Epoxy emerged as the best natural fiber composite, with a TOPSIS score of 0.2686, indicating a performance gap of approximately 231% in favor of the synthetic composite. Comprehensive sensitivity analysis across four weighting scenarios (Equal, Technical, Environmental, and Economic) confirmed the stability of the reinforcement rankings, with Carbon (PAN-HM) remaining the top synthetic fiber and flax the top natural fiber across all scenarios. The findings contribute to the growing body of knowledge on sustainable aerospace materials and provide practical guidance for UAV designers seeking to optimize material selection for micro-turbojet engine inlet components, supporting the development of more environmentally responsible UAV designs while maintaining the performance requirements for safe and reliable operation. Full article

The issue of near-field electromagnetic interference (EMI) is being made worse by the widespread use of highly integrated electronic devices, including commercial LED displays. Although highly conductive pristine carbon networks, like recycled carbon fiber nonwovens (rCFNWs), have excellent far-field shielding effects (~43 dB) in theory, their purely reflection-oriented mechanisms cause severe secondary signal interference in practical near-field applications due to reflective inefficiency. This study suggests employing a custom-formulated silicone-carbon nanotube (Si-CNT) composite to switch to an absorption-based shielding mechanism in order to get around these restrictions. This study used FE-SEM, Raman spectroscopy, XPS, ICP-AES, FTIR, and TGA-DTG to systematically investigate the morphological, chemical, and thermal properties of the rCFNW, Si-CNT composite, and a Cu-integrated variant (Si-CNT-Cu). Surface reflection was greatly reduced by adding CNTs to the silicone matrix, converting the materials into absorption-oriented localized shielding composite materials (~16 dB). Both the designed Si-CNT membrane and the Cu-integrated Si-CNT-Cu product totally eliminated the 850 MHz switching noise peak (>40 dBuV) in real near-field tests of commercial LED modules running under worst-case conditions (5.36 A). Additionally, the bare Si-CNT membrane showed a lower coefficient of thermal expansion (CTE) in the thermomechanical analysis (TMA) than the Si-CNT-Cu product. On the other hand, the macroscopic integration of Cu wires in the Si-CNT-Cu composite provided remarkable thermomechanical stability, preventing thermal softening by preserving an exceptionally high storage modulus of 97.54 MPa at 198 °C, according to dynamic mechanical analysis (DMA). These findings show that using absorptive suppression to overcome near-field inefficiency is a very successful method for creating dependable EMI shielding composite materials in high-power electronic systems. Full article

Battery packs for new energy vehicles have evolved from simple load-bearing and protective assemblies into multifunctional safety structures integrating structural support, crash protection, thermal-runaway mitigation, flame retardancy, electrical insulation, electromagnetic interference shielding, waterproof sealing, and long-term reliability. Fiber-reinforced polymer composites are promising for upper covers, underbody shields, trays, cross beams, side frames, and local protective structures because of their low density, corrosion resistance, design flexibility, and functional-integration potential. However, composite-part performance is strongly governed by forming. Resin flow, impregnation, curing or cooling shrinkage, fiber orientation, filler dispersion, and interfacial bonding may induce voids, dry spots, resin-rich regions, delamination, warpage, and fiber waviness, thereby affecting load bearing, sealing, thermal protection, and durability. This review focuses on composite-forming technologies for new energy-vehicle battery packs. It summarizes component-level service requirements and material systems and compares representative forming routes, including sheet molding compound (SMC), prepreg compression molding/wet compression molding (PCM/WCM), resin transfer molding/high-pressure resin transfer molding (RTM/HP-RTM), vacuum-assisted resin transfer molding (VARTM), long-fiber thermoplastic direct processing (LFT-D), glass-mat thermoplastic (GMT), thermoplastic sheet forming, pultrusion, and multi-material joining. These routes are evaluated from six dimensions: material form, forming cycle, typical defects, representative mechanical performance, applicable components, and engineering maturity. The review further discusses defect mechanisms, performance effects, detection and control methods, and the roles of in-line monitoring, non-destructive testing, process simulation, machine learning, and digital twins in closed-loop quality manufacturing. Finally, engineering challenges are examined in multi-material joining, thermal-safety integration, low-carbon recycling, and standard certification. Composite-material battery-pack structures should therefore be developed as coordinated design and closed-loop manufacturing systems linking materials, processes, defects, performance, and validation. Full article

The functions of noncoding variants associated with complex traits in livestock remain poorly understood. In this study, we investigated two candidate noncoding variants within the XKR4-CHCHD7 locus identified from our previous analysis. Dual-luciferase reporter assays demonstrated allele-specific regulatory activity of these two regions in bovine muscle satellite cells (BMSCs), 293T cells, and C2C12 cells. Endogenous deletion of the candidate regions using a clustered regularly interspaced short palindromic repeats (CRISPR)-based high-fidelity Cas12Max (hfCas12Max) system revealed that the region containing chr14:22840845 (SNP-0845) exerted broader effects on BMSC function including reduced proliferation and migration, altered cell-cycle progression, and enhanced myogenic differentiation. Expression screening of candidate effector genes further identified PENK and TMEM68 as downstream candidate genes for SNP-0845. Rescue experiments further showed that PENK exerted stronger recovery effects than TMEM68 on the proliferation and migration defects caused by deletion of this region, supporting PENK as a major candidate effector downstream of the SNP-0845. Functional assays showed that PENK knockdown impaired BMSC proliferation and migration while promoting myogenic differentiation, whereas PENK overexpression partially reversed these effects. In vivo Penk knockdown reduced quadriceps femoris weight and altered muscle fiber composition in mice. Collectively, our findings suggest that a noncoding regulatory region modulates BMSC fate and muscle growth-related processes through PENK. Full article

Lupins have been cultivated since ancient times. Poland ranks second in the world in terms of lupin cultivation area (second only to Australia), particularly for narrow-leaved lupin. It is used in various industries. The purpose of this review is to analyze data on the chemical composition of narrow-leaved lupin in comparison with other species of this genus, as well as to identify its potential applications. The literature data characterize narrow-leaved lupin in terms of its content of protein, lectins, fat, carotenoids, phytosterols, fiber, sugars, alkaloids, vitamins, flavonoids, phenolic compounds, volatile organic compounds, and micro- and macronutrients. Due to its interesting qualitative and quantitative composition, this species may play a significant role in human nutrition—not only as an alternative source of protein, but above all as a source of health-promoting compounds. Studies conducted on humans and animals have demonstrated a wide range of biological effects, including anti-inflammatory, antioxidant and cholesterol-lowering effects. In addition, in vitro studies suggest anticancer effects. Among the tangible outcomes of research and commercialization efforts is the availability on the consumer market of food and cosmetic products containing lupin. Due to its properties, this species has a wide range of applications. However, to meet the requirements of various industrial sectors, a collaborative approach is necessary among plant breeders, scientists, and industry representatives working to improve this species. Only through joint efforts can the use of narrow-leaved lupin be expanded. Full article

Fused filament fabrication (FFF) has become an important additive manufacturing technique for producing functional polymer-composite components. The tensile performance of carbon fiber-reinforced polyethylene terephthalate glycol (PETG/CF) fabricated by FFF depends on multiple printing parameters. This study presents an integrated experimental and predictive framework for investigating the effects of extrusion temperature, printing speed, layer height, infill pattern, and infill density on the tensile strength of PETG/CF containing 15 wt.% carbon fiber. A mixed-level Taguchi L36 orthogonal array was employed, comprising 36 experimental runs with three independently printed specimens per run, resulting in 108 ASTM D638 Type V specimens. Analysis of variance showed that the printing speed had the largest contribution to tensile strength (20.51%), followed by layer height (18.29%). The highest tensile strength of 33.225 MPa was obtained using grid infill, 60% infill density, 270 °C extrusion temperature with 40 mm/s printing speed, and 0.3 mm layer height. An artificial neural network (ANN) was developed for the tensile-strength prediction, achieving R = 0.9801, R² = 0.9569, and MAPE = 1.52% for the overall dataset. Scanning electron microscopy qualitatively revealed bead-interface defects, fiber pullout, and localized void-like features. The proposed framework provides a systematic approach for evaluating process-parameter effects and predicting tensile strength within the investigated PETG/CF parameter domain. Full article

The pollution generated during the synthesis and processing of synthetic fibers demands new raw materials for the textile industry. Natural fibers are a good solution due to their increased comfort while wearing, and their biodegradability. However, the use of some of these fibers, such as cotton or ramie, comes with limitations like competition with edible plants for land and water during cultivation, and the pollution generated during their processing. Thus, finding other sources of fibers that do not compete with plants for food seems to be a good solution. Pineapple fibers represent a good example of synergy, with the fruit being intended for food while the leaves, once considered waste, can be valorized as fibers. This paper describes the progress in research on obtaining pineapple fibers and their properties depending on their mode of preparation. The technical progress in preparing pineapple fibers is emphasized. Their application in textile materials, alone or as composites, is presented. According to the literature, pineapple fibers may also be applied in other fields besides the textile industry. Moreover, the fact that waste is the raw material for these fibers represents a great asset, and the development of new technologies for their production and application is recommended. Full article

Durum wheat straw is an abundant by-product in Mediterranean cereal systems, but its low protein and high fiber content limit its use as ruminant feed. Integrating forage legumes as living mulches in durum wheat may enhance its feeding value through the addition of nutrient-rich legume biomass. A two-year field trial evaluated three forage legumes (Vicia sativa L., Trifolium michelianum Savi, Trifolium subterraneum L.) grown as living mulch with organic durum wheat (Triticum turgidum subsp. durum (Desf.) Husn.) under two NPK fertilization rates (target 60 and 120 kg N ha⁻¹), with or without rhizobial inoculation. Chemical composition and forage quality indices were determined for sole-wheat straw (SB) and legume biomass (LB) and subsequently used to estimate the nutritional characteristics of wheat straw–legume biomass mixtures (TSB). Biomass production was significantly affected by legume species in the first growing season and by legume species and rhizobial inoculation in the second, with Vicia sativa consistently showing the best performances. Correlation analysis showed that increasing LB contribution was significantly associated with all forage quality indices of the resulting TSB. These results indicate that rhizobially inoculated forage legume living mulch may improve the potential use of wheat straw as an on-farm feed resource in Mediterranean organic farming. Full article