Search Results (4,189)

This study investigates the influence of PLA flowability and talc content on the performance of compostable thermoplastic starch/poly(butylene succinate) (TPS/PBS)-based systems for rigid applications. Different PLA grades with varying melt flow index (PLA23, PLA8 and PLA70) and talc contents (0, 5 and 10 wt%) were incorporated. Twelve formulations were compounded by twin-screw extrusion and processed by injection moulding. FTIR confirmed the coexistence of TPS, PBS and PLA phases without evidence of chemical interactions. Morphological analysis showed that PLA flowability plays a key role in phase distribution, with higher-flow PLA promoting improved dispersion and interfacial adhesion, while talc addition (5 and 10 wt%) increased structural heterogeneity; at higher loadings, particularly, DSC analysis revealed that talc acted as a nucleating agent for the PBS phase, increasing crystallisation temperatures from approximately 73 °C to 81 °C depending on formulation. Mechanical results showed that Young’s modulus increased from approximately 1.4 GPa to 2.7 GPa with decreasing PLA flowability and increasing talc content. Formulations containing low-flow PLA reached tensile strengths close to 32 MPa, although elongation at break decreased to values near 2%. In contrast, high-flow PLA formulations exhibited a more balanced mechanical response, with elongation values up to approximately 8%, associated with improved phase dispersion. Hybrid PLA systems showed intermediate behaviour, reaching elongations up to 22% while maintaining modulus values around 1.8 GPa. Talc provided additional reinforcement but reduced deformation capacity. HDT values remained relatively constant, indicating limited improvement in thermomechanical resistance despite increased stiffness. These results demonstrate that the combined control of PLA molecular characteristics and talc content enables tuning of the mechanical and thermomechanical performance of TPS/PBS/PLA/talc systems for rigid packaging applications. Full article

Modern prosthetic dentistry has been significantly reshaped by adhesive dentistry, CAD/CAM technologies, and advanced ceramic materials, leading to the development of minimally invasive all-ceramic restorative approaches. However, the longevity of the adhesive interface is fundamental to the long-term effectiveness of these restorations. With a focus on bond durability and clinical performance, this narrative review aims to evaluate modern adhesive strategies, tooth preparation requirements, and cementation techniques in all-ceramic minimally invasive restorations. Methods: A narrative review of the literature was performed using Google Scholar, Web of Science, and PubMed/MEDLINE databases. Publications from 2000 to 2026 were analysed. In vitro research, narrative reviews, and systematic reviews related to adhesive systems, resin cements, CAD/CAM materials, and minimally invasive prosthodontic principles were the core subjects of the research. Results: The findings indicate that material selection, surface conditioning techniques, and cementation methods have a significant impact on the clinical effectiveness of all-ceramic restorations. Retention and marginal sealing are greatly enhanced by resin-based adhesive systems. Nevertheless, hydrolytic degradation, procedure sensitivity, and substrate-related factors remain a challenge to the adhesive interface. Advances in CAD/CAM and ultra-conservative designs, like occlusal veneers and partial-coverage restorations, have increased treatment alternatives while ensuring acceptable functional and aesthetic results. Conclusions: Minimally invasive all-ceramic restorations represent a conservative and clinically effective treatment approach in modern prosthodontics. Their long-term performance is primarily dependent on adhesive interface stability and adherence to evidence-based clinical protocols. Continued developments in adhesive materials and ceramic systems are expected to improve bond durability and broaden clinical indications. Full article

This study validated a controlled in vivo test protocol using a patented particulate exposure chamber (Korean Patent No. 10-2020-0068941) to evaluate the anti-particulate adhesion efficacy of a cosmetic sunscreen formulation (SPF 50+, PA++++). The primary aim was methodological—to demonstrate that the chamber system can reliably detect differences in carbon black adhesion under standardised conditions. A split-site paired design was applied to 22 healthy adult females (mean age 60.3 ± 5.2 years; range 46–68 years). Carbon black particles (≤10 μm) were dispersed via a precision dual-stage pneumatic nozzle within a sealed chamber (22 ± 2 °C; 50 ± 5% RH). Between-group comparison was assessed by the Wilcoxon signed-rank test (primary) and the generalised estimating equation (GEE) model (complementary between-group comparison per institutional SOP). The treated site showed a 55.0% reduction in carbon black adhesion (treated: 4243 ± 2225 pixels; control: 9430 ± 4769 pixels, SE = 4.82, 95% CI: −64.4 to −45.6, Wald Z = −11.41, p < 0.001; Cohen’s d = 2.43). The Wilcoxon test confirmed the result independently (Z = −4.11, p < 0.001). All 22 subjects (100%) showed consistent reduction directionality (individual rates: 22.6–74.2%; mean 51.8%; median 52.3%). Bootstrap resampling (n = 10,000), outlier-exclusion, and exact sign test sensitivity analyses all confirmed robustness. These findings represent proof-of-concept methodological validation applied to a single product under accelerated exposure conditions. Full article

Background: The generation of durable and hemocompatible small-diameter vascular grafts remains a major challenge in current vascular tissue engineering, as clinically available synthetic grafts are lacking hemocompatibility resulting in limited long-term patency. In recent years, fibrin has emerged as a promising scaffold material for various tissue engineering approaches due to its autologous nature, controllable fabrication, and mechanical properties. However, although pivotal for the translation into clinical application, systematic evaluation of hemocompatibility in fibrin-based small-caliber grafts is still missing. Methods: Here, the hemocompatibility of small-diameter fibrin-based grafts with and without heparin coating was compared to the current gold standard for prosthetic small-diameter vessel replacement in the form of heparin-coated ePTFE grafts using the Chandler Loop circulation model with human whole blood. Cell adhesion of thrombocytes, erythrocytes, and leucocytes was compared. Platelet activation, activation of the complement system, and plasmatic coagulation activity were assessed by ELISA analyses for P-Selectin, complement sC5b-9, and thrombin–antithrombin complex, respectively. Scanning electron microscopy (SEM) was performed to evaluate interactions and thrombocyte activation on the luminal graft surfaces. Results: The short-term hemocompatibility of the fibrin-based grafts with respect to the cell-count, activation of the coagulation pathways, and thrombocyte activation was comparable to the heparin-coated synthetic grafts even without heparin coating of the bioartificial grafts. Conclusions: The findings of this early-stage analysis support fibrin as a promising scaffold material for small-diameter vascular tissue engineering. Full article

Non-uniform fiber deposition remains a critical limitation in electrospun poly(lactic acid) (PLA) coating systems. In the present study, experimental characterization was combined with numerical simulations to evaluate the influence of electrospinning parameters on fiber morphology, coating uniformity, and thickness distribution. A 3% PLA solution was electrospun under different processing conditions by varying the applied voltage, needle-to-collector distance, flow rate, and deposition time. The resulting coatings were further analyzed using numerical simulations performed with ANSYS Fluent 2020 R2 software. The results demonstrated that both solution-related and operational parameters strongly influence fiber morphology and spatial deposition behavior. Increasing the applied voltage promoted the formation of thinner fibers; however, excessively high voltage values generated jet instability associated with fiber fragmentation and spray formation. Furthermore, the deposited fibrous layers showed preferential accumulation in the central region of the collector, together with a gradual decrease in coating thickness toward the peripheral areas. A strong correlation was observed between the numerical simulations and the experimental results, confirming the reliability of the proposed modeling approach. Among the investigated conditions, the optimal electrospinning parameters were identified as an applied voltage of 16 kV, a needle-to-collector distance of 17 cm, and a flow rate of 2.5 mL/h. These conditions enabled the formation of homogeneous PLA nanofibers with minimal structural defects and improved substrate adhesion. The combined experimental and numerical approach provides valuable insight into the optimization of electrospinning parameters governing fiber formation and deposition behavior. Full article

Polymer-based sandwich structures are widely used for their lightweight and tailorable properties, but interfacial failure phenomena often govern their performance. Among these, Mode I skin/core debonding is a critical mechanism that limits structural reliability. This review provides a unified and critical assessment of experimental methodologies for Mode I fracture characterisation, focusing on the ASTM D8637/D8637M standard and alternative setups, including Double Cantilever Beam (DCB), Single Cantilever Beam (SCB), and Climbing Drum Peel (CDP) tests. Alongside the influence of geometrical factors, processing conditions and intrinsic polymer properties on Mode I characterisation are detailed. Conventional DCB setups are shown to introduce mixed-mode effects due to asymmetric loading. In contrast, the modified DCB-UBM setup achieves near-pure Mode I conditions at the expense of increased complexity. Comparative analysis indicates that the SCB configuration with a roller base outperforms the standardised flexible-rod setup, particularly for specimens with non-linear responses. The review also indicates that Mode I debonding behaviour is strongly influenced by several factors, including interfacial adhesion quality, constituent material properties, manufacturing-induced defects, specimen configurations, and environmental factors. Therefore, the interpretation of debonding performance requires a comprehensive structure–property–processing framework. Moreover, geometric constraints imposed by ASTM D8637/D8637M are also revisited, demonstrating that reduced-dimension specimens can yield comparable fracture toughness, thereby enabling greater design flexibility. Additionally, while the standard prescribes Modified Beam Theory (MBT) and Area Method (AM) for initiation and propagation, both methods provide comparable propagation toughness under linear conditions. For non-linear systems, alternative data reductions based on CDP concepts, with the SCB–roller base setup, are effective. Based on this assessment, key challenges and potential improvements are identified, guiding the development of more accurate and reliable testing methodologies for polymer sandwich structures. Full article

Galectins are β-galactosyl-binding lectins with key roles in immune regulation and as pattern recognition receptors. To address their potential role(s) in viral infection of mucosal epithelia we currently investigate adhesion and entry mechanisms of the infectious hematopoietic necrosis virus (IHNV) using the zebrafish (Danio rerio) model system. We previously reported the recognition of IHNV envelope glycoprotein by the zebrafish galectin Drgal1-L2 and its inhibitory activity for viral adhesion to epithelial cells. Subsequently, we determined the structure of Drgal1-L2 and proposed a mechanism for Drgal1-mediated inhibition of IHNV spike fusion to the host epithelial cell. We now show that Drgal1 can also hinder viral adhesion and infection by binding to glycans on the host cell surface and epidermal mucus. We identified fibronectin, the reported IHNV receptor, as the cell surface glycoprotein recognized by Drgal1-L2. Surprisingly, IHNV also adhered in vitro to purified β1integrin, and pre-exposure of either IHNV or the immobilized β1integrin to Drgal1-L2 hindered IHNV adhesion. Binding of either anti-fibronectin or anti-β1integrin antibodies to the cell surface partially inhibited IHNV adherence. Drgal1-L2 also hindered IHNV adhesion by binding to mucus glycans. Taken together, our results suggest complementary mechanisms by which Drgal1-L2 may protect mucosal epithelial cells against IHNV infection and tentatively identify β1integrin as a novel receptor for IHNV. Full article

This paper proposes a physically based hybrid architecture for controlling mobile robot drives. It combines a model-based controller, an adaptive neural network compensator for residual dynamics, and a Lyapunov-based stability supervision mechanism. Unlike existing hybrid control approaches, the proposed architecture implements a structured injection of neural network correction directly into the physical drive model with a controlled Lyapunov-based adaptation constraint. A mathematical model of the electromechanical drive of a differential mobile platform is developed, taking into account electrical and mechanical dynamics, wheel-to-surface contact interaction, and the system’s energy characteristics. Numerical simulation results demonstrate that the hybrid approach improves tracking accuracy, improves transient response, and ensures stable operation of the control system under parametric uncertainty, adhesion changes, and external disturbances. The proposed architecture maintains the physical interpretability of the model while simultaneously enhancing the system’s adaptability. The obtained results confirm the effectiveness of the developed method and its potential for application in control systems for mobile robotic platforms. Full article

A controlled composting biodegradation system was implemented to evaluate a wood–plastic composite (WPC) composed of wood fibers and recycled HDPE (rHDPE), in accordance with ASTM D5338, by measuring CO₂ capture over 45 days. This evaluation was complemented with mechanical and physicochemical characterization, including stereomicroscopy/SEM, mass loss, water absorption, contact angle, tensile strength, FTIR, TGA, and DSC. The results showed 6.12% biodegradation, classifying the material as neither biodegradable nor compostable. SEM analysis revealed increased surface roughness, cracks, and microbial-like structures, together with a 10% decrease in contact angle. The mechanical properties declined by 33% (tensile strength), despite only 1.26% mass loss, which was attributed to weakening of the matrix–fiber interfacial adhesion due to water absorption. TGA, DSC, and FTIR supported the interpretation that degradation occurred preferentially in the wood fibers. Full article

Background/Objectives: Image-based finite element analysis (FEA) is increasingly used in dental biomechanics; however, its reliability is often limited by insufficient experimental benchmarking and a lack of standardized workflows. This study aimed to quantitatively benchmark a Cone beam computed tomography-based (CBCT) finite element pipeline using experimentally measured strain in restored human molars. Methods: Extracted human mandibular molars were restored using a total-etch adhesive system and bulk-fill composite resin. Specimen-specific finite element models were generated from CBCT data using a standardized segmentation and meshing workflow. Numerical simulations were compared with experimentally measured strain obtained during mechanical loading using Digital Image Correlation. Agreement between numerical and experimental data was assessed using regression analysis, Bland–Altman analysis, and equivalence testing. Results: A total of 304 spatially clustered paired measurements nested within 16 specimens were analyzed. FEM predictions showed strong correlation with experimental data (r = 0.91–0.97; R² up to 0.937) and low relative error (~5–6%). The model systematically overestimated deformation by approximately 10–15%. Equivalence was confirmed within ±15% for dentin and composite, and within ±20% for enamel. Bland–Altman analysis revealed proportional bias and heteroscedasticity, particularly in dentin. Conclusions: The proposed CBCT-based finite element workflow demonstrates strong benchmarking agreement with experimental measurements and provides reproducible estimates of mechanical behavior within defined tolerance limits under controlled experimental conditions. Despite systematic overestimation, the model exhibits stable and reproducible behavior under controlled conditions. These findings support the use of experimentally benchmarked, image-based FEA workflows in dental biomechanical research. Full article

Microplastics (MPs) are increasingly recognized as pervasive co-contaminants in aquatic environments, yet their impacts on advanced oxidation processes remain poorly understood. Herein, we systematically investigate the role of representative MPs in diclofenac (DCF) degradation within a permanganate–manganese dioxide (PM-MnO₂) catalytic system. Results show that PM alone exhibits limited reactivity toward DCF, while MnO₂ significantly enhances DCF degradation. In the absence of MnO₂, MPs increase PM consumption but do not influence DCF degradation, indicating that MPs primarily act as competing oxidant sinks. In contrast, under MnO₂ catalytic conditions, the effect of MPs strongly depends on their interaction with MnO₂. Pre-adhesion of MPs onto MnO₂ suppresses DCF degradation by blocking active sites and inhibiting interfacial electron transfer. However, when MPs are introduced without pre-adhesion, no inhibition is observed; instead, a slight enhancement in DCF removal occurs. This promotion is attributed to in situ oxidation of MPs, which consumes PM and simultaneously generates secondary MnO₂ colloids that provide additional reactive interfaces. Further analysis reveals that PM consumption is decoupled from DCF degradation due to multi-pathway oxidant partitioning, including DCF oxidation, MP oxidation, and Mn redox cycling. These findings demonstrate that MPs can act as both inhibitors and promoters depending on their interaction mode with catalysts, highlighting the importance of catalyst accessibility and reaction sequence. This study provides new insights into the complex roles of MPs in catalytic oxidation systems and offers guidance for applying PM-based technologies in realistic water matrices. Full article

Fiber contamination originating from disposable dental microapplicators has received limited attention despite its potential influence on adhesive procedures. The aim of this pilot in vitro study was to evaluate fiber-like structure release associated with different microapplicator types during the application of universal adhesive systems. Three universal adhesives (Clearfil Universal Bond Quick, Gluma Universal, and G-Premio BOND) and five microapplicator types (X-Slim, Clinique, Prima, Single TIM, and ZerofloX silicone-bristle microapplicators) were evaluated. A total of 75 adhesive applications were performed on standardized sandblasted glass substrates under controlled laboratory conditions. Adhesives were actively applied for 10 s, and fiber-like structures were quantified microscopically using ImageJ software. Statistical analysis included descriptive statistics, two-way ANOVA, and Tukey post hoc testing (α = 0.05). Significant differences were observed among microapplicator types. X-Slim applicators produced the highest fiber counts, whereas Single TIM applicators demonstrated substantially lower values. No detectable fiber-like structures were observed in specimens treated with the ZerofloX silicone-bristle microapplicator. Adhesive system type showed a comparatively smaller influence on fiber counts than microapplicator design. Within the limitations of this pilot in vitro study, microapplicator type appeared to be the primary factor influencing visible fiber contamination during adhesive application. Further studies are required to determine whether the contamination patterns observed influence adhesive performance under clinically relevant conditions. Full article

This study investigates the design and performance of lime mortars incorporating multi-phase change material (multi-PCM) systems as thermally responsive rendering materials for building-envelope applications under variable conditions. Moving beyond conventional single-PCM lime mortar approaches, this work proposes a controlled multi-PCM design framework in which a fixed total PCM dosage is distributed across selected phase-transition windows. Mortars combining PCMs with different transition temperatures (5–25 °C and 18–25 °C) were produced using two PCM types: silica-supported form-stable systems and polymeric-shell microencapsulated systems supplied as powders or aqueous slurries. All formulations contained 20% PCM and were optimized with polymeric additives, including a polycarboxylate ether-based superplasticiser and a starch-derived adhesion enhancer, to ensure suitable workability and applicability as rendering materials. Microstructural analyses showed that form-stable PCMs generated more heterogeneous pore structures, whereas polymeric-shell microencapsulated systems maintained pore structures similar to PCM-free mortars. Mortars containing metakaolin exhibited enhanced mechanical performance and durability, in some cases outperforming reference mortars, highlighting the importance of matrix refinement in the successful incorporation of multi-PCM systems. Thermal characterization revealed that form-stable systems produced broader phase transitions due to component interactions, while polymeric-shell microencapsulation preserved distinct transitions and enabled a wider, more controllable activation range. Under dynamic thermal conditions (−10 to 50 °C), all multi-PCM mortars demonstrated effective temperature buffering, achieving reductions of up to 1.5 °C during heating and 1.1 °C during cooling. Environmental and economic analyses highlighted that the benefits of PCM incorporation depend on matching PCM transition temperatures to specific climatic and application requirements. These findings position multi-PCM lime mortars as a promising route towards climate-adapted, thermally responsive renders with distributed and tailorable activation profiles. Full article

In the present study, the development of a high-density polyethylene/polylactic acid/titanium dioxide (HDPE–PLA–TiO₂) composite proposed for pellet-based additive manufacturing and the evaluation of its thermal and mechanical behavior are presented and discussed. The study was designed to address the printability limitations of high-HDPE-content systems, particularly extrusion instability and weak interlayer adhesion. PLA was introduced to improve processing stability, while TiO₂ was incorporated as an inorganic filler. The selected formulation allowed the production of filaments, pellets, and 3D-printed specimens. Thermal analysis indicated the absence of significant mass loss below approximately 300 °C under the applied thermogravimetric/differential thermal analysis (TG/DTA) conditions, suggesting that no major mass-loss degradation occurred within the selected processing window. However, this result should be interpreted as macroscopic thermal stability and does not exclude possible molecular-level changes in PLA during processing. Tensile tests indicated strengths of 20–25 MPa for extruded filaments and 7.86–10.36 MPa for printed specimens, with an elastic modulus of approximately 2 GPa. Scanning Electron microscopy equipped with Energy Dispersive X-Ray Spectroscopy (SEM/EDS) observations revealed a heterogeneous fracture morphology with cavities, microcracks, fibrillar structures, and local Ti-rich regions, supporting the influence of morphology and filler distribution on the mechanical response of the printed specimens. The results indicate improved printability, adequate thermal behavior for the selected processing conditions, and moderate but reproducible tensile performance, highlighting the potential of this formulation for pellet-based additive manufacturing applications where processability and rigidity are more relevant than maximum tensile strength. Full article

Engineered bamboo composites (EBCs) are increasingly considered as sustainable alternatives to tropical hardwoods in structural applications. In jacking systems, performance is primarily governed by compression perpendicular-to-grain (bearing), although improper use may introduce flexural demands. This study evaluates the bearing and flexural behavior of Dragonwood, a commercial parallel strand bamboo (PSB), in comparison to Ekki (Lophira alata) through 120 full-scale tests. Dragonwood exhibited higher mean bearing capacity than Ekki, with yield stresses exceeding those of Ekki by over 60%, indicating strong potential for bearing-dominated applications such as in jacking. However, face-bonded specimens showed sensitivity to glue-line orientation, resulting in flexural strength reductions of up to 42% and undesirable shear failures. Increasing adhesive content and pressing pressure in the manufacturing process did not eliminate this behavior. Single-lift specimens removed the glue-line and showed improved failure behavior in flexure, although with reduced strength. The results demonstrate that manufacturing strategy heavily influences PSB performance. While single-lift Dragonwood products show the most potential, further testing under bearing is required before its suitability for jacking applications can be fully established. Full article