Search Results (346)

This study evaluated how a partial substitution of pea protein isolate (PPI) with brewer’s spent grain (BSG) or barley rootlets (BRs) affects high-moisture meat analogues (HMMAs). PPI was substituted with 10% and 20% with BSG or BRs, respectively. Extrudates were produced on a co-rotating twin-screw extruder at maximum temperatures of 140 °C and 160 °C. Extrudates were assessed for colour, moisture, firmness and fibre morphology. Furthermore, the technofunctional and nutritional properties of the raw materials were determined. Extrudates with BSG produced the darkest colour, whereas PPI and BR formulations exhibited the lightest. A stronger reddish tint was observed at 160 °C, while the colour within the yellow–blue spectrum was largely temperature-independent. Firmness was generally higher at 160 °C, consistent with lower end-product moisture. Side stream addition lowered protein content and weakened fibre formation, with the effect most pronounced for BRs. Overall, formulation was the dominant factor influencing lightness, while temperature modestly increased redness and firmness. Preliminary sensory evaluation supported these trends. Extrudates produced at 140 °C were perceived as having a more fibrous structure. Higher substitution levels resulted in a weaker, more crumbly texture. With respect to the environmental assessment, a 20% replacement of PPI with BRs or BSG reduced overall environmental impacts by up to 19% and climate impacts by up to 16%. With regard to the novel food status, the EU Novel Food Status Catalogue classifies BSG as not novel, whereas BRs are not novel only when used in food supplements. Any other food uses, other than as, or in, food supplements, might considered to be novel and consequently might need to be authorised under the novel food regulation framework prior to market placement. Full article

This preliminary study investigates the viability of substituting high-performance Aalborg white Portland cement (CEM I 52.5 R) with five diverse industrial byproducts: wood ash, silica waste, clay brick, glass fibre, and calcined sewage sludge ash. Sewage sludge ash was produced in a laboratory from two different sludges from wastewater treatment plants in the Latvian cities of Jelgava and Liepaja. The research evaluates the influence of substitution levels ranging from 5% to 20% on the rheology of fresh material and its early-age mechanical performance (day 7). Results indicate that particle morphology largely dictates workability; porous and angular materials, such as wood ash, clay brick, and sewage sludge ash, reduce flowability, whereas non-absorbent milled glass fibres unexpectedly improve spread diameter. Regarding mechanical performance, glass fibre and clay brick waste demonstrated the highest potential, exceeding the 48–62 MPa reference compressive strengths by achieving up to 69 MPa at a 10% substitution level. Conversely, wood ash and silica waste exhibited significant strength degradation at higher substitution levels, due to agglomeration and high water demand. This approach not only identifies viable waste streams for cement substitution but also diverts significant industrial waste from landfills, thereby reducing CO₂e emissions and advancing more sustainable construction practices. Full article

This study investigated the surface characteristics and wettability behaviour of grey poplar (Populus × canescens) compared with spruce (Picea abies) in order to evaluate its potential as an alternative raw material for bonded structural wood products. Surface roughness was analysed on freshly planed radial surfaces using amplitude and functional roughness parameters, complemented by multivariate factor analysis and dynamic contact angle measurements. The results showed that grey poplar sapwood exhibited roughness values comparable to spruce (R_a ≈ 6–7 μm; R_z ≈ 35–40 μm). Grey poplar heartwood showed slightly higher roughness and greater variability, which can be attributed to its heterogeneous anatomical structure characterised by larger vessel elements and higher extractive content. Hybrid roughness parameters indicated favourable bonding-related surface characteristics in sapwood due to lower R_pk values, suggesting fewer protruding fibres, while higher R_vk values reflected the diffuse-porous anatomical structure of poplar. Static contact angle measurements revealed higher initial values for grey poplar (37.9° for heartwood and 41.9° for sapwood) compared with spruce (31.7°), indicating lower initial wettability with polar liquids. However, dynamic measurements demonstrated faster early-stage spreading in grey poplar heartwood (Δθ = 26.1° within the first second) compared with sapwood (16.8°) and spruce (17.5°), suggesting that vessel-driven capillary uptake may facilitate liquid penetration once wetting begins. Overall, the results indicate that grey poplar—particularly its sapwood fraction—exhibits surface characteristics comparable to spruce after planing. Despite slightly lower initial wettability, its spreading behaviour and surface morphology indicate favourable conditions for adhesive interaction. These findings support the potential use of grey poplar as an alternative raw material for laminated structural products such as glulam or bonded panels, provided that adhesive application parameters are properly adjusted. Full article

Neutrophil extracellular traps (NETs) critically influence thrombosis by promoting platelet aggregation, fibrin formation, and thrombus stabilisation. However, primary human neutrophils present experimental limitations, including short lifespan ex vivo and ethical concerns. In this article, we discuss the available data on PLB-985 cells, a neutrophil-like model with potential to replace human neutrophils in research. Additionally, we present novel structural comparisons showing that both PLB-985- and human neutrophil-derived NETs significantly increased fibrin fibre thickness compared to thrombin-only controls, with similar fibre morphology across conditions. Notably, we also see spherical particles resembling microvesicles within PLB-985-derived NETs, suggesting potential additional procoagulant effects via microvesicle-associated tissue factor level in these cells. New and existing data presented in this article suggest that differentiated PLB-985 cells are able to effectively replicate key structural and functional aspects of human neutrophil NETs. These observations support the use of PLB-985 cells as an ethical, reproducible, and practical alternative for in vitro studies of NETs. Further characterisation is required to determine differences between human neutrophils and neutrophil-like models in macrovesicle formation and implication in NET-related thrombosis research. Full article

Polyester resin composites containing expanded graphite often exhibit reduced mechanical strength due to the porous structure of the filler. The aim of this study was to enhance mechanical performance without compromising electrical behaviour. Although carbon fibre and expanded graphite are chemically identical carbon allotropes, their distinct morphologies motivated the use of carbon fibre to reinforce expanded graphite-filled polyester composites. To examine the role of expanded graphite porosity, ultrasonicated EG was used to produce exfoliated, lower-porosity particles, while vacuum processing was applied to remove entrapped air prior to curing. Adding 0.5–5 wt% milled carbon fibre increased electrical conductivity by up to three orders of magnitude relative to neat polyester while maintaining 70–80% of the original specific strength at moderate fibre contents. Ultrasonicated EG reduced tensile strength by more than 50% at 5 wt% loading and decreased conductivity due to additional grain boundary formation. Vacuum-processed EG not only provided slight mechanical enhancements but also significantly improved electrical properties by lowering surface resistance by 6–10 orders of magnitude, reaching the tens-of-Ω range at 3–5 wt% EG. This performance is comparable to previously reported conductive EG/polymer systems, which exhibit surface resistances of 10–10² Ω at 5 wt% EG. This systematic comparison offers practical guidelines for balancing conductive percolation and mechanical reinforcement in expanded graphite polyester composites. Full article

This experimental study investigates the influence of selected bed joint reinforcement systems on the evolution of damage and crack development in masonry elements subjected to axial compression. Autoclaved aerated concrete masonry samples reinforced with steel truss reinforcement, unidirectional carbon fibre mesh and steel cords embedded in a fibreglass matrix were tested and compared to an unreinforced reference specimen. Full-field deformation and strain localisation were monitored using digital image correlation (DIC). The results indicate that bed joint reinforcement does not lead to a measurable increase in compressive load-bearing capacity, as differences in ultimate load remain within experimental uncertainty. However, clear differences in the evolution and spatial distribution of damage were observed. Steel truss reinforcement promoted strain redistribution and delayed localisation of tensile strains, while the remaining reinforcement systems exhibited only limited influence on crack morphology. The findings confirm that bed joint reinforcement in compressed masonry should be classified as a nonstructural solution and demonstrate the diagnostic value of full-field deformation monitoring for assessing damage evolution and crack control in masonry structures. Full article

This study experimentally investigates the settling behavior of bent (V-shaped and curved) and straight rods in a quiescent fluid at low and finite Reynolds numbers ($\mathrm{Re}<3$). The impact of the rod morphology on the terminal settling velocity and drag coefficient was examined, with a particular focus on V-shaped rods compared to straight rods of the same dimensions (diameter and length) and curved rods of the same dimensions and projected area. The results show that V-shaped rods consistently settle faster than straight rods, with velocity differences influenced by the bend angle. This velocity difference reaches a maximum of 57% for a V-shaped rod with a diameter of 0.50 mm, an aspect ratio of 90, and a bend angle of 45 degrees. When compared to curved rods, V-shaped rods exhibit slightly higher terminal velocities, with a maximum difference of 4% in this study, attributed to differences in mean inclination angles. Furthermore, the drag coefficient trends reflect the interplay between the settling velocity and projected area changes with the rod geometry. A new semi-empirical model with an RMS error of 7.1% was also developed to predict the drag coefficients and terminal velocities of straight and bent rods within the ranges studied. These findings and the model presented underscore the significance of the fibre shape in accurately predicting settling dynamics, with implications for atmospheric transport modeling and industrial applications involving fibrous particles. Full article

Soil–steel interface shear governs load transfer and long-term serviceability in piles, retaining systems, and buried infrastructure; yet the large-displacement interface mechanics of fibre-reinforced sands remain poorly resolved, limiting sustainable design. This study couples large-displacement ring-shear testing with physics-guided hybrid AI to quantify and predict the peak and residual resistance of sand–polypropylene fibre mixtures sliding on smooth and rough steel. Two quartz sands with contrasting particle morphology were tested under 25–200 kPa normal stress and 0–1.0% fibre content, producing a design-oriented database that captures post-peak evolution and residual states. The experiments reveal a strongly nonlinear reinforcement law: an optimum fibre range enhances dilation, stabilises the shear band, suppresses post-peak softening, and increases residual strength, whereas excessive fibres disrupt the granular skeleton and reduce mobilisation efficiency. Roughness and confinement act as amplifiers, intensifying fibre-driven dilation and asperity interlock. To translate mechanisms into prediction, three strategies were benchmarked: a deep neural network (DNN), the Physics-Guided Neural Additive Model (PG-NAM++), and the physics-anchored Residual-DNN that learns only the correction to a mechanical baseline. Residual-DNN achieved the tightest agreement and the highest physical consistency for both peak and residual strength, enabling robust parameter selection with reduced uncertainty and overdesign. The combined experimental–AI framework advances the United Nations Sustainable Development Goals (SDGs) by supporting SDG 9 through resilient, innovation-led infrastructure design and contributing to SDG 12 by enabling optimised (rather than maximal) use and reuse of reinforcement materials within circular ground-improvement practice. Full article

A tissue-engineered heart valve is a fully functional tissue facilitated through the cultivation of autologous cells on appropriate scaffolds. Scaffold’s surface charge and wettability are the main factors that significantly affect cell adhesion, which is known to be favourable on hydrophilic surfaces. Moreover, biocompatible scaffolds that induce minimal immunogenic response are also essential for successful tissue engineering (TE). However, commonly used biocompatible polymers with preferable bulk properties lack desirable surface properties. For example, poly-ε-caprolactone (PCL), which is widely used as a scaffold in TE, is known for its satisfying structural and mechanical properties, but due to its surface characteristics, cell attachment and, consequently, cell growth on this polymer are limited. In this study, we investigated the possible effect of H₂-N₂ plasma treatment on the surface wettability of electrospun PCL nanofibres to see the feasibility of improvement in cell adhesion and proliferation. Our results showed an increase in the hydrophilicity of the 650 nm PCL specimens after plasma treatment, which was followed by a significant enhancement in cell attachment without altering PCL mechanical properties. Plasma surface modification is a promising approach that can be used to improve hiMSCs growth without altering the desired bulk properties and fibre morphology of 650 nm PCL specimens. Full article

Cortical microtubules comprise heterodimeric units of α- and β-tubulin which have been shown to guide the deposition of cellulose microfibrils in plant cell walls where their arrangement is important in determining cell morphology and cell wall properties. Tubulin genes are highly expressed in woody tissues and a functional study has demonstrated a role for a β-tubulin gene family member in affecting the orientation of cellulose microfibrils in wood fibre cells, an important trait in determining the mechanical properties of wood fibres. To further understand the role of tubulins in plant cell trait determination, this study identified and investigated the expression of the α- and β-tubulin gene families in Eucalyptus and then, using transgenesis techniques, investigated the role of specific eucalypt tubulin isoforms in determining secondary cell wall traits of wood fibres in plant stems. This study found that the α- and β-tubulin gene families in Eucalyptus are relatively small compared to other species and show higher expression in woody stem tissue when compared to leaf. Functional studies revealed that cambial cells transformed with α- and β-tubulin overexpression and knockdown vectors, either on their own or in combination, lead to changes in the angle of microfibrils in the secondary cell wall of wood fibre cells with Class I- and Class I-like gene family members explicitly involved. This study demonstrates the importance of tubulins in determining the mechanical properties of wood fibres through a mechanism involving specific tubulin isoform expression during wood fibre formation. Full article

This study evaluated the effect of rearing conditions with outdoor access on carcass traits, technological meat quality, and muscle fibre morphology in broiler chickens. Hubbard JA757 broilers were reared until 81 days of age under either control or experimental conditions. Both groups were housed indoors under identical management until day 35; thereafter, the experimental group had access to an outdoor paddock, while the control group remained indoors. At 81 days of age, birds were slaughtered, carcass composition was recorded, and breast (pectoralis major) and thigh (biceps femoris) muscles were analyzed for pH, colour, cooking loss, and shear force. Muscle fibre characteristics were assessed histochemically. Control birds showed higher slaughter and chilled carcass weights, whereas experimentally reared birds exhibited higher carcass yield, lower breast proportion, higher thigh proportion, and reduced abdominal fat. Experimental rearing was associated with higher L* values, higher shear force, and lower cooking loss in both muscles. In the pectoralis major, fibre density was higher in controls, while fibre diameter was higher in the experimental group. In the biceps femoris, the experimental group showed a higher proportion of oxidative βR fibres and larger fibre cross-sectional areas. These results demonstrate that the rearing system influences carcass composition, technological meat properties, and muscle fibre characteristics, leading to distinct phenotypic and technological differences between the groups. Full article

The growing demand for sustainable alternatives to synthetic composites has increased the interest in natural-fibre-reinforced composites (NFRCs), due to their reduced environmental impact. This study presents a comparative investigation of the mechanical properties of mono-fibre and intraply sisal/flax hybrid composites as cost-effective bio-based solutions. Flax offers high tensile performance but is constrained by higher cost and geographical availability. Sisal, on the other hand, is widely available at lower cost, but exhibits a coarser morphology and reduced processing versatility. Mechanical testing demonstrated that intraply hybrids achieved well-balanced performance, with reduced flax content still delivering competitive tensile strength and stiffness when compared to the higher performing mono-fibre flax composites. However, sisal-rich and hybrid laminates outperformed mono-fibre flax composites in transverse and shear behaviour, with the 67% sisal/33% flax hybrid composite exhibiting the highest transverse properties and the 33% sisal/67% flax hybrid achieving the highest shear properties. Rule-of-mixtures models predicted longitudinal tensile behaviour effectively, while Halpin–Tsai models successfully estimated shear but not transverse and compressive properties. Compressive strength showed limited variation across configurations. Failure analysis identified intra-yarn fracture in flax, limited resin infiltration in sisal, and compressive failure modes such as brooming and microbuckling. Overall, intraply sisal/flax hybrid mats provide a structurally efficient, sustainable, and economically viable alternative to mono-fibre natural composites. Full article

The textile industry generates significant volumes of waste, making the development of reliable methods to evaluate biodegradability a pressing need. While standardised protocols exist for plastics, no specific methodologies have been established for textiles, and the quantification of non-degraded residues is commonly based on mass loss: a measurement that is prone to recovery errors. This study investigated the biodegradation of cotton, polyester, and cotton/polyester blend fabrics in soil under thermophilic conditions using a combined methodological approach. Carbon mineralisation was quantified through a respirometric assay that was specifically adapted for textile substrates, while residual solid fractions were assessed in situ by X-ray microtomography (micro-CT), thus avoiding artefacts associated with sample recovery. Complementary analyses were performed using SEM and FTIR to characterise morphological and chemical changes. Results showed substantial biodegradation of cotton, negligible degradation of polyester, and intermediate behaviour for the cotton/polyester blend. Micro-CT enabled the visualisation of fibre fragmentation and the quantification of the residual. The integration of respirometric, imaging, and spectroscopic techniques provided a comprehensive assessment of textile biodegradability. This study highlights the potential of micro-CT as a non-destructive tool to improve the accuracy and robustness of textile biodegradability assessment by enabling direct quantification of the residual solid fraction that can support future LCA studies and the development of standardised protocols for textile biodegradability. Full article

This study investigates the design of bio-hybrid sandwich composites by combining polyester/glass skins with cores reinforced by continuous Musa paradisiaca fibres. The aim is to quantify how fibre weight fraction and alkaline surface treatment control the Charpy impact performance of these systems. Sandwich laminates were manufactured with three fibre loadings in the core (20, 25 and 30 wt.%), using fibres in the as-received condition and after alkaline treatment in NaOH solution. Charpy impact specimens were machined from the laminates and tested according to ISO 179-1. Fibre morphology and fracture surfaces were examined by scanning electron microscopy, while Fourier-transform infrared spectroscopy was used to monitor changes in surface chemistry after alkaline treatment. The combined effect of fibre content and treatment on absorbed energy was assessed through a two-way analysis of variance. Increasing Musa paradisiaca fibre content up to 30 wt.% enhanced the impact energy of the sandwich composites, and alkaline treatment further improved performance by strengthening fibre–matrix adhesion and promoting fibre pull-out, crack deflection and bridging mechanisms. The best Charpy impact response was obtained for cores containing 30 wt.% NaOH-treated fibres, demonstrating that surface modification and optimised fibre loading are effective design parameters for toughening polyester/glass bio-hybrid sandwich composites. Full article

Oats (Avena sativa L.) are a rich source of β-d-glucans, dietary fibre, proteins, and lipids. However, the behaviour of these components in wheat–oat composite systems during baking, particularly with regard to matrix-dependent analytical responses, remains unclear. This study evaluated the compositional changes, technological performance, and sensory quality of wheat bread enriched with various forms of oat. Composite flours containing 5–15% wholegrain oat flour, commercial oat bran, milled commercial oat flakes, or milled sprouted oat grain (sprouted under laboratory conditions for three days at 25 °C) were prepared using the Slovakian oat cultivar ‘Peter’. The raw materials, flour blends, and baked breads were analysed for β-d-glucans (BG), total dietary fibre (TDF), starch, proteins, and lipids using standardised enzymatic, gravimetric, and polarimetric methods. Bread quality was assessed through loaf volume measurements and a sensory evaluation using a 5-point hedonic scale by seven trained panellists. Multivariate statistical analysis was applied to integrate compositional, technological, and sensory data. Compared to wheat flour (0.24% BG and 3.45% TDF), the incorporation of oats significantly increased the contents of BG, TDF, proteins, and lipids, with oat bran showing the strongest enrichment effect (owing to 15.69% TDF in the raw material). Baking induced oat-form-dependent changes in the measured BG and TDF content. The level of BG diminished in wholegrain oat blends but increased or remained stable in bran-rich systems. This reflects differences in matrix structure and analytical extractability, rather than true compositional gains. Meanwhile, starch content consistently declined across all composite breads. Fibre-rich formulations exhibited reduced loaf volume and altered both bread geometry and morphology, particularly at 15% substitution. Breads containing 5% oat flour or moderate levels of oat bran (5 or 10%) were considered the most acceptable in terms of nutritional enhancement and quality attributes. Germinated oat breads showed the greatest technological impairment and the lowest sensory scores. Overall, moderate oat enrichment strikes a balance between nutritional improvement and technological performance without significantly compromising sensory quality. These findings emphasise the significance of matrix effects when interpreting standard total dietary fibre and β-d-glucans analyses and offer an integrated analytical and technological framework for the rational design of fibre-enriched cereal products. Full article