Search Results (508)

Traditionally, repairing coated substrates requires completely removing damaged, wear-resistant layers before recoating. This process leads to high costs, extended downtime, and material waste. Flexible brazing tapes, which are composed of alloy powder and an organic binder, offer an alternative to full coating removal for targeted repairs. Despite this, the process of vacuum brazing these tapes may lead to the formation of defects, including pores caused by trapped gases or residual binder, which compromise coating durability and corrosion resistance. This study focuses on the utilization of laser remelting as a method for post-processing nickel- and iron-based mixed alloy brazing tapes, with the aim of improving the integrity of the coating. Surface quality was assessed via microscopy and microhardness testing by systematically varying laser power, scanning speed, and hatch distance. Among the parameters studied, the most suitable laser parameter combination was found to be 350 W laser power, 250 mm/s scanning speed, and a hatch distance of 0.02 mm. These parameters yielded crack- and pore-free coatings with a remelting depth of 160.3 ± 17.2 µm and a microhardness of 701 ± 23 HV1, which is an 85% increase over as-brazed samples. Wear testing revealed a reduced coefficient of friction, and electrochemical corrosion tests showed lower corrosion current density and enhanced repassivation behavior in remelted coatings. These improvements demonstrate that laser remelting significantly enhances the microstructure, hardness, wear resistance, and corrosion performance of brazed coatings, providing an effective method for localized repair while minimizing material consumption and processing duration. Full article

Continuous unidirectional (UD) thermoplastic composite tapes are increasingly used in aerospace, automotive, and energy applications because of their high specific strength, low weight, recyclability, and compatibility with automated manufacturing. Since final component performance strongly depends on tape quality, reliable defect characterization and detection are essential. In this study, manufacturing-induced defects in polypropylene-based UD tapes reinforced with carbon and glass fibers were investigated using real images acquired directly from laboratory-scale production without synthetic data. Defects related to interfacial integrity, matrix distribution, fiber architecture, and surface irregularities were systematically analyzed, and a practical four-class defect taxonomy was established. To enable automated inspection under limited-data conditions, lightweight YOLOv8, YOLOv11, and the new YOLO26 models were comparatively evaluated using a UD tape-specific augmentation strategy combining physically constrained Albumentations and on-the-fly augmentation. Among the tested models, YOLO26-s achieved the best overall performance, reaching a mean mAP@0.5 of 0.87 ± 0.03, outperforming YOLOv11 (0.83) and YOLOv8 (0.78), with 0.90 precision and 0.85 recall. Interfacial (0.92 mAP) and matrix-related (0.90 mAP) defects were detected most reliably, whereas fiber-related (0.89 mAP) and surface defects (0.79 mAP) remained more challenging, particularly in glass-fiber-reinforced tapes due to transparency-masking effects. The results demonstrate the potential of compact deep learning models for computationally efficient and manufacturing-relevant in-line quality monitoring of UD tape production. Full article

With Aligned Formable Fibre Technology (AFFT^™), fibers are reformatted into highly oriented epoxy prepreg tapes, enabling the structural reuse of recycled composite waste. The present study investigates whether discontinuous fiber laminates produced with AFFT^™ can be characterized and optimized with the same finite-element workflows long established for continuous fiber composites and whether the resulting structures meet demanding stiffness targets. Initially, various manufacturing methods were adopted, including vacuum bagging, compression molding at 7 bar to simulate autoclave conditions, and compression molding at 90 bar, comprising the three most reasonable manufacturing processes for AFFT^™ laminates. Experimentally measured orthotropic properties were introduced into a finite-element model representing an idealized bicycle top tube, which was chosen as a case study. A genetic algorithm screened candidate stacking sequences, minimizing the combined bending-and-torsion deflection. The best lay-ups reduced deformation by more than 30% compared to a quasi-isotropic baseline, showing that well-oriented short fibers can significantly contribute to the stiffness of composites. Tubes produced with the optimized lay-up were tested in three-point bending tests, and the measured stiffness matched simulations within 5%. These results confirm a key point for sustainable engineering: despite the absence of continuous fibers, conventional simulation strategies accurately predict the performance of AFFT^™ laminates and can be used as the basis for effective genetic optimization. This validation is significant: it enables the design of stiff, high-performance structures from recycled materials using established, cost-effective methods. By proving that optimization strategies developed for traditional continuous fiber composites apply to AFFT^™, this study offers a trusted and accessible pathway to scale circular economy solutions in next-generation composite products. Full article

Digital trade rules have proliferated rapidly, yet the literature still treats institutional environments and firm behavior in a comparative-static manner, overlooking the feedback loops and stock-like accumulation dynamics through which regulatory openness shapes firm capabilities over time. Drawing on general systems theory and system dynamics, this paper models the digital trade rule regime as an “institutional system” and the overseas subsidiary network of digital MNEs as an “enterprise system,” linked through three capability stocks (market, production, knowledge), cross-subsystem coupling, absorptive capacity modulation, and five internal feedback loops. We derive a reduced-form dynamic panel equation mapping structural parameters onto estimable coefficients, and test its static counterpart using data on 6850 subsidiaries of UNCTAD’s top 100 digital MNEs (2000–2024) matched with the TAPED database. Three findings emerge. First, institutional openness—measured by rule depth and breadth—exerts a positive causal effect on subsidiary ROA, surviving IV estimation and multiple robustness checks. Second, the effect transmits through market expansion, production efficiency, and knowledge accumulation channels, confirmed by Baron–Kenny mediation with Sobel tests. Third, the New Digital Economy (NDE) module displays point estimates 4–8 times larger than other modules, and joint Wald tests reject coefficient equality, providing qualified support for Meadows’ leverage-point hierarchy. Our contribution lies in bridging system dynamics modeling with econometric causal identification, and in unifying transaction cost theory, the OLI paradigm, and the knowledge-based view within a single open-system framework. Full article

Long-term operation of drip emitters under sediment-laden water conditions readily induces particle deposition and clogging, leading to discharge reduction and deterioration of irrigation uniformity. To clarify the temporal evolution and spatial distribution of clogging and to support structure-oriented anti-clogging improvement, three integrated drip tape emitters with different labyrinth-channel geometries were tested at sediment concentrations of 1, 2, and 3 g·L⁻¹ under a constant pressure of 100 kPa. The average relative discharge ratio (Dra) and Christiansen’s uniformity coefficient (CU) were continuously monitored, and cross-sectional observation and numerical simulation were combined to identify dominant deposition hotspot regions within the labyrinth channel. The results showed that increasing sediment concentration significantly accelerated clogging development and shortened operating lifetime. At 1 g·L⁻¹, the times required for the three emitter types to reach the clogging criterion of Dra < 75% were 120, 81, and 107 h, respectively, whereas at 3 g·L⁻¹ these values decreased to 39, 42, and 39 h. CU continuously declined with operating time and, in some treatments, responded earlier than Dra to system deterioration. Sediment deposition was mainly concentrated in the inlet section and bend regions, indicating that these locations were the dominant hotspots for clogging initiation and propagation. These findings demonstrate that clogging in drip emitters is jointly regulated by sediment load and labyrinth-channel geometry, and that hotspot-based structural optimization provides an effective basis for improving anti-clogging performance under sediment-laden water conditions. Full article

Body weight (BW) is an important trait in dairy cows; however, large-scale direct measurements are challenging. Heart girth (HG) has been proposed as a practical indicator of BW, but limited information is available for lactating cows, especially for locally adapted breeds. This study aimed to develop equations to estimate BW from HG in lactating Holstein, Simmental, and Rendena cows. A total of 293 cows (94 Holstein, 52 Simmental, and 147 Rendena) were selected from 6 farms equipped with an automatic milking system located in northern Italy. Both HG and BW were recorded on the same day, with HG measured using a tape and BW using a scale integrated into the automatic milking system. For each breed, linear, quadratic, and cubic regressions of BW on HG were tested, adjusting for days in milk and parity effects. The coefficient of determination and the root mean square error were reported. The best predictive performance was obtained with models adjusted for both days in milk and parity, with the highest accuracy achieved for Holstein and Simmental cows. These results corroborate that HG is a reliable predictor of BW in lactating cows of these breeds. Full article

Background/Objectives: Senescence has been recently described in brain cells following ischemic stroke. The potential of targeting senescence as an effective therapeutic approach in the treatment of ischemic stroke requires further investigation. This study evaluated the effects of the senolytic drug navitoclax after experimental ischemic stroke. Methods: Navitoclax was injected into male young Wistar rats at doses of 10 and 30 mg/kg (i.p.). to evaluate its pharmacokinetics, cerebral levels and potential to cause thrombocytopenia. Subsequently, a second group of rats underwent 60 min of transient middle cerebral artery occlusion (tMCAO). Navitoclax (10 mg/kg, i.p.) or vehicle was injected every other day between days 3 and 13 after tMCAO. Neurofunctional performance, infarct size, and senescence markers were assessed on day 14. Results: Navitoclax (10 mg/kg) administration resulted in a maximum plasma concentration of 0.702 mg/L and half-life of 11.33 h. Additionally, a brain concentration of 0.04 ± 0.02 µg/g was detected. Moderate thrombocytopenia was induced by 10 mg/kg, and to a greater extent by 30 mg/kg. Navitoclax (6 × 10 mg/kg) improved neurofunctional impairment, as indicated by significant decrease by 66% in the total time for the tape removal test, and significantly reduced infarct area by 52% when compared to vehicle. Moreover, navitoclax significantly reduced levels of SA-β-gal (by 80%), lipofuscin (by 91%), and Checkpoint kinase 2 (Chk2; by 69%) in the ischemic hemisphere. Conclusions: Navitoclax protects the brain after ischemic stroke by improving neurofunctional outcome and reducing infarct size, which is associated with reducing senescence markers. Although moderate thrombocytopenia warrants caution, targeting senescence emerges as a promising therapeutic strategy for ischemic stroke. Full article

Background: Patellofemoral pain syndrome (PFPS) is a common musculoskeletal disorder that involves various biomechanical factors, including the altered positioning of the patella, weakness of the lower extremity muscles, delayed activation of the vastus medialis muscle, and excessive pronation of the foot. Although the short- and long-term effects of external support among the recommended conservative treatment methods for PFPS have been examined, there remains a lack of consensus regarding their impacts. This study was conducted to investigate the immediate effects of braces and rigid taping applied to control pain on proprioception, functional status, and balance in patients with PFPS, and to compare these outcomes with normative values obtained from healthy individuals. Methods: The study included 18 patients with PFPS and 18 healthy individuals who met the inclusion criteria. Through randomization of the intervention sequence, patients were evaluated under conditions of rigid taping, support, or without any support. Their pain levels before and after the application were assessed using the Visual Analog Scale; their functional status was evaluated with the Kujala Patellofemoral Scoring, the 10-Step Up Test, and the Squat; their balance performance was measured using the Y-Balance Test and the Single Leg Stance Test; and their proprioception was assessed with the Joint Position Sense Test. Results: It has been determined that rigid taping and bracing have similar effects in the immediate management of pain, proprioception, functional status, and balance issues in patients with PFPS. The interventions were observed to bring patients’ static balance and proprioception parameters closer to the values seen in healthy individuals. Conclusions: Rigid taping and bracing are both effective interventions in the management of PFPS, offering benefits such as pain relief, prevention of proprioceptive deficits, mitigation of balance impairments, and enhancement of functional outcomes. The selection of the most appropriate modality should be based on the individual patient’s characteristics and tolerance levels. Full article

Background: This study evaluates short-term skin compatibility and biophysical changes in new cosmetic preparations containing PRF and EGF, conducted through in vivo studies. Material and Methods: The study involved 20 healthy volunteers (aged 20–40) who received three identically packaged creams to be applied for a period of four weeks to specific facial areas: formulation 1: base formulation (control); formulation 2: base formulation human epidermal growth factor (EGF) loaded; and formulation 3: base formulation platelet-rich fibrin (PRF) loaded. Skin assessments were conducted at baseline (week 0) and at weeks 1, 2, and 4. Transepidermal water loss (TEWL), skin hydration using corneometry to determine the moisture content of the stratum corneum, skin elasticity using a cutometer to measure the skin’s ability to return to its original state after deformation, and dermal bioavailability were measured. EGF concentration in the stratum corneum will be measured using the tape-stripping method followed by HPLC (high-performance liquid chromatography) analysis. Results: A significant decrease in TEWL was observed for all tested formulations (24%, 37%, and 34%, for formulations 1, 2, and 3, respectively), indicating improved skin barrier function. Formulation 3 showed the highest increase in skin hydration (by 95%), followed by formulation 2. Both formulations 2 and 3 demonstrated improvements in skin elasticity, with formulation 3 showing the greatest enhancement. EGF concentration in the stratum corneum increased over the four-week period, reaching equilibrium with the product concentration by week four. Conclusions: The in vivo instrumental compatibility studies confirmed that the new cosmetic formulations were well tolerated and associated with short-term improvement in selected skin parameters. Full article

Earthen immovable cultural relics, such as murals and painted clay sculptures, are prone to deterioration (e.g., efflorescence, flaking, and cracking) under long-term preservation conditions. While conventional restoration materials primarily offer reinforcement, they fail to regulate the migration of soluble salts within the relics, which is the main cause of such damage. Herein, aimed at protecting the painted sculptures and murals of the Yungang Grottoes, nano calcium-aluminum layered double hydroxides (Ca-Al LDHs) were prepared, and their effectiveness in regulating salt crystallization within the earthen ground layer, as well as their reinforcement performance were investigated. Simulated salt crystallization tests revealed that coating the ground layer with Ca-Al LDHs delayed salt-induced damage time by 150%. This can be attributed to the ability of Ca-Al LDHs to adsorb sulfate ions from soluble salts, thereby inhibiting the crystallization of magnesium sulfate on the surface of the ground layer. After curing Ca-Al LDHs-coated samples at 35 °C and 55% relative humidity (RH) for 7 days, their surface Leeb hardness increased by 3.1%, and the weight loss rate (measured via tape peeling test) decreased by 38.3%. These results indicate that the surface bonding strength was enhanced following Ca-Al LDHs coating, with the underlying mechanism being the transformation of part of the LDHs into calcium carbonate under the influence of water and carbon dioxide. This study demonstrates that Ca-Al LDHs not only suppress magnesium sulfate crystallization but also provide effective surface consolidation, showing promising potential for application in conserving painted sculptures and murals at the Yungang Grottoes. Full article

Enterobiasis, caused by the nematode Enterobius vermicularis, remains a widespread public health issue, yet data regarding its genetic structure in Southeast Europe are scarce. This study presents the first molecular and phylogenetic characterization of E. vermicularis isolates from Bulgaria. Between 2022 and 2025, perianal tape test samples were collected from 128 individuals (92.2% of whom were children) with enterobiasis from 17 regions of the country. Molecular identification was performed via nested PCR targeting a 324 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene, followed by Sanger sequencing. Phylogenetic relationships were analyzed using Maximum Likelihood (IQ-TREE), and population genetic indices were calculated using DnaSP v6. Phylogenetic analysis revealed that all 128 Bulgarian isolates belong to genotype B, clustering closely with sequences from other European and Asian countries. Genetic diversity analysis showed remarkably low variation, with a haplotype diversity (Hd) of 0.1507 ± 0.0416 and a nucleotide diversity (π) of 0.00082 ± 0.00015. Among the 11 identified haplotypes, a single dominant haplotype (Hap_1) accounted for 92.2% of all samples and was distributed across all sampled geographic regions. Tajima’s D was significantly negative (−2.314, < 0.05), suggesting a recent population expansion or purifying selection. The dominance of genotype B and the extremely low genetic diversity suggest a recent introduction or clonal expansion of E. vermicularis in Bulgaria. These findings provide essential baseline data for monitoring transmission dynamics and implementing effective control strategies in the Balkan region. Full article

Unidirectional glass fiber-reinforced thermoplastic (UGFT) composite tapes are promising recyclable structural materials for applications such as composite pressure pipes. However, their durability under hydrothermal environments remains a critical concern. This study emphasizes metrology-driven evaluation of aging behavior in polypropylene-based UGFT tapes. Specimens were conditioned at 95 °C in a deionized-water environment for up to 4 weeks, and multiple complementary measurement techniques were applied to quantify degradation. Mass-change metrology was performed to characterize water uptake kinetics and establish diffusion-driven aging progression. Tensile testing enabled quantitative assessment of mechanical strength retention, defining a >25% reduction in strength as a threshold for significant deterioration. Acoustic emission (AE) acted as the central non-destructive monitoring method, capturing high-fidelity waveforms generated during loading. AE waveform descriptors, such as amplitude, rise time, and frequency content, served as measurable indicators of internal damage mechanisms including matrix cracking, interfacial debonding and fiber breakage. To process large AE datasets, principal component analysis was used for dimensionality reduction, followed by k-means clustering to group signals by damage type. Optical microscopy provided microstructural verification of these classifications. The integrated metrological framework demonstrates a reliable pathway to monitor, identify, and quantify damage evolution in hydrothermally aged UGFT structures. Full article

Two commercial adhesive tape strips (Fungi-Tape^TM and Filmoplast^® P) and a polyvinyl alcohol–borax (PVA-B) gel were tested as novel physical cleaning alternatives to micro-aspiration for removing visible fungal colonisation from a cotton canvas. In addition, clove essential oil (CEO) and Cyrene™ were incorporated in the PVA-B gel for testing the potential of each to improve fungal cleaning. For the trials, canvas mock-ups were separately inoculated with two fungal species identified as Penicillium chrysogenum and Aspergillus westerdijkiae. Removal of fungi and related impacts were evaluated by DOM, FESEM, ATR-FTIR and ImageJ software. Inhibition of fungal spores and residual growth were assessed by in vitro growth tests and CLSM. Removal of A. westerdijkiae was more effective than removal of P. chrysogenum, especially for dense coverage. Both tape strips removed slightly more fungus than micro-aspiration, except for dense coverage of P. chrysogenum. The PVA-B gel, both with and without CEO or Cyrene™, yielded the best (similar) results, removing the fungal material found on the surface and subsurface of canvas without damaging the canvas fibres. Although further testing is required, the antifungal activity of PVA-B gel+ Cyrene™ seems comparable to that of PVA-B gel+ CEO, the former being especially effective against A. westerdijkiae. Full article

The objective of this study was to conduct preliminary tests to determine if differing concentrations of atrazine affected locomotion and/or food-seeking behaviors of juvenile (second and third instar) virile crayfish after a 4-day (96 h) exposure period. After exposing crayfish to 0, 5, 10, 20, and 100 parts per billion (ppb) atrazine treatments, crayfish were tested and video-taped individually in a flow-through test arena before and during introduction of a food odor. Walking speeds (pre-odor, post-odor, and pre- to post-ratios), time to locate the food-odor source, and success rates in finding the food odor were compared among atrazine treatments. Pre-odor walking speeds, time to locate the food-odor source, and post-odor walking speeds did not differ among the control and treatment crayfish. Crayfish success rates in locating the food-odor source also did not differ among treatments and controls. Crayfish in controls and all atrazine treatments walked slightly, but not significantly, faster after a food odor was presented than before. Virile crayfish food-seeking behavior and locomotion were not affected after exposures up to 100 ppb atrazine, so these behaviors likely are not useful indicators of crayfish exposure to environmentally relevant (5 ppb or less) atrazine levels like those measured periodically in regional streams. Expanded replication and testing may be helpful in assessing the effects of atrazine (especially concentrations at or above 100 ppb) on the food-seeking behaviors of this species, although simple behavioral studies of crayfish may not be sensitive enough to assess the true effects of atrazine on aquatic organisms and communities. Full article

During industrial construction, steel measuring tapes are frequently exposed to alkaline cement environments, leading to rapid degradation of protective coatings and corrosion of the steel substrate. In this study, acrylic–amino resin composite coatings incorporating three different inhibitor systems (RZ/ZMP, RZ/ZPO, and RZ/ZPA) were prepared, and their corrosion resistance in alkaline media was systematically evaluated. The microstructure and composition of the coatings were characterized by SEM, EDS, and XRD, while surface wettability was assessed by water contact angle measurements. Corrosion protection performance was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and long-term alkaline immersion tests. The results show that the incorporation of inhibitors significantly enhances the corrosion resistance of the coatings. Compared with the inhibitor-free acrylic–amino resin coating, the corrosion current density of the RZ/ZPA coating decreases by approximately 1.9 times, while that of the RZ/ZPO coating decreases by about 1.7 times. EIS analysis further reveals that the RZ/ZPO/acrylic–amino resin coating exhibits the highest coating resistance (1.41 × 10⁷ Ω·cm²), which is approximately 4.2 times higher than that of the inhibitor-free coating and 188 times higher than that of the steel substrate, indicating the strongest ion-blocking capability. Based on combined electrochemical parameters and long-term alkaline immersion behavior, the corrosion resistance of the coatings increases in the following order: acrylic–amino resin coating < RZ/ZPA < RZ/ZMP < RZ/ZPO. Overall, the synergistic effect of multiple inhibitors significantly improves both the electrochemical corrosion resistance and long-term alkaline durability of acrylic–amino resin coatings. Full article