Search Results (5,018)

In engineering practice, additively manufactured (AM) metal and metal alloy structural components, which often contain geometric discontinuities to fulfil functional requirements, are subjected to cyclic service loads. Among the possible loading configurations, far-field Mode I loading is frequently considered as a nominal reference condition. Within this context, a methodology for the fatigue assessment of notched AM Scalmalloy components subjected to Mode I far-field loading is proposed, combining the Strain Energy Density (SED) approach with a multiaxial critical plane-based fatigue criterion. The fatigue assessment is carried out at a verification point whose position is defined as a function of the characteristic length of the SED control volume for Mode I loading, determined through two alternative procedures, and of the surface roughness of the component. The proposed methodology is validated against experimental fatigue data available in the literature for AM Scalmalloy specimens featuring a circumferential semi-circular notch and subjected to Mode I far-field cyclic loading, which induces a locally multiaxial stress state at the notch root, given that the formulation does not rely on material-specific assumptions and could in principle be extended to other notched AM metal and metal alloy components. Full article

Vibrational energy harvesters typically generate only low voltages and low powers, making high-efficiency power conversion essential to extract usable energy from such sources. To address this challenge, suitable rectifier circuits must be designed to operate efficiently under low-voltage conditions. In this study, three rectifier topologies—a standard bridge rectifier and two alternative designs from the literature—were investigated in a two-step methodology: first, measurements were performed in the laboratory using a function generator to simulate controlled excitation conditions, followed by experiments with a real electromagnetic energy harvester. Component-level testing allowed the identification of the most suitable components for each topology, highlighting the influence of parameters such as MOSFET gate-source threshold voltage on overall performance. Using the selected optimal components, the circuits were then compared under varying excitation amplitudes and load conditions. Small modifications were introduced to the literature designs to improve switching behavior and reduce conduction losses. Across all tested conditions, the active-diode rectifier consistently achieved the highest harvested power, demonstrating both the effectiveness of component selection and the practical benefit of the adapted topology. These results provide a systematic basis for designing high-efficiency rectifiers for low-voltage vibrational energy harvesting applications. Full article

This study explores the viability of condensate petroleum, an ultra-light hydrocarbon derived from natural gas production, as an alternative diesel engine fuel. The researchers tested six different fuel blends, increasing the condensate volume by 10% increments, in a compression ignition engine under three distinct load conditions (25%, 50%, and 75%) to evaluate both combustion characteristics and emission performance. The results demonstrate that condensate blends significantly enhance key combustion parameters. The heat release rate, in-cylinder pressure, and in-cylinder temperature all increased, with the highest heat release rate improvement of 35.6% observed at a 75% load using a 60% condensate petroleum blend. However, increasing the condensate ratio also extended ignition delay times and raised the ringing intensity, which peaked with a 34.7% increase at a 25% load. Brake thermal efficiency improved at lower and medium loads—achieving a maximum 11.2% increase with the 50% condensate petroleum blend at 50% load—but decreased when the engine reached 75% load. In terms of environmental impact, the condensate blends proved largely beneficial. Carbon monoxide emissions dropped by 57.9% (at 75% load, 60% condensate petroleum), smoke opacity decreased by 72.6% (at 25% load, 40% condensate petroleum), and hydrocarbons fell by 34.4% (at 50% load, 60% condensate petroleum). The primary drawback was that nitrogen oxide emissions worsened, increasing by 20.4% at 75% load with the 50% condensate petroleum blend. Overall, the study concludes that the effects of condensate petroleum are highly acceptable, making it a promising alternative fuel and additive for diesel engines. Full article

This paper presents a systematic application of the Homotopy Perturbation Method (HPM) to the nonlinear static analysis of cantilever beams subjected simultaneously to three coplanar follower loads: an axial force H, a transverse force V, and a bending moment M₁. The studied configuration introduces complex mathematical self-coupling, as the bending moment depends on the solution of the differential equation even in its boundary conditions (γ₁), transforming the problem into a nonlinear one that is resistant to standard analytical methods. The primary methodological contribution of this work is the successful extension of the HPM framework to treat, within a unified mathematical formalism, this complete loading case, which has practical applications in compliant mechanisms, micro-electromechanical systems (MEMSs), and auxetic structures. The paper provides a complete mathematical formulation and explicit derivation of the HPM solution terms up to the third order and a rigorous demonstration of the method’s convergence, with quantitative error estimates and the establishment of a practical domain of validity, γ₁ < 30°, for an accuracy below 0.5%. As a direct consequence of this analytical advancement, we derive a series of practical engineering tools: nomograms, simplified empirical formulas, interaction diagrams, and a systematic six-step design procedure, which includes an adaptive algorithm for selecting the auxiliary parameter η to optimize convergence. The solution’s structure also lends itself to AI-based optimization frameworks, demonstrating how HPM solutions can serve as a foundation for machine learning surrogates and automated multi-objective optimizations. HPM proves to be a robust and efficient alternative, providing semi-analytical solutions in the form of convergent series without requiring an explicitly small physical parameter. This enables a direct parametric understanding of the structural response and offers rapid tools for the conceptual and preliminary sizing phases, thereby complementing the intensive numerical methods used in the final design stages. Full article

Background/Objectives: Lung cancer remains a major global health burden, largely driven by cigarette use. Although electronic cigarettes (e-cigarettes) are viewed as safer alternatives due to their reduced chemical load, growing evidence shows their vapor can disrupt cellular transcriptomes, including long noncoding RNAs (lncRNAs). In this study, we examined the regulation and function of vape-associated lncRNA transcript 1 (VALT1), a novel transcript upregulated in the oral transcriptomes of e-cigarette users and similarly elevated in non-small-cell lung cancer (NSCLC) tumors. Methods: Publicly available RNA-seq datasets were analyzed, and VALT1 was identified as an e-cigarette-responsive lncRNA. Its dose-dependent induction by e-cigarette smoke extract (eCSE) and cytoplasmic localization were confirmed via RT-qPCR. Its effects on cancer-associated phenotypes including proliferation, ROS detoxification, resistance to apoptosis, migration, cytoskeletal disorganization, and nuclear remodeling were assessed through overexpression and siRNA-mediated knockdown in A549 and BEAS-2B cells. Results: Acute eCSE exposure induced a biphasic, dose-dependent increase in VALT1 expression, accompanied by enhanced proliferation, ROS detoxification, apoptosis resistance, migration, cytoskeletal disorganization, and nuclear remodeling in A549 cells. VALT1 overexpression reproduced these phenotypes in both cell lines without eCSE treatment, whereas knockdown attenuated them. VALT1 promoted survival under cytotoxic stress in A549 but not BEAS-2B cells. Conclusions: These findings support an active role for VALT1 as an e-cigarette vapor-upregulated transcript that contributes to its phenotypic readout and enhances cellular survival under extracellular chemical stress—thereby aggravating tumorigenic phenotypes even in the absence of mutations that contribute to malignant transformation. Full article

Concrete-encased steel (CES) bridge piers can be considered as a robust alternative to traditional reinforced concrete sections, especially in regions prone to seismic activity. CES piers combine the ductility of steel with the compressive strength of concrete, offering improved energy dissipation and resilience during earthquakes. Given the lack of CES design specifications in the Canadian design code, it is crucial to compile a body of knowledge describing the behavior of the CES bridge pier in order to facilitate the codification of the design guide. This study assesses the seismic performance of CES rectangular bridge piers with a focus on how variations in the steel section configuration affect the pier’s overall behavior under seismic loads. To conduct this assessment, a fiber element model was employed to model CES bridge piers subjected to seismic loading. The thickness and height of the web and the width and the thickness of the flanges of the I-shape steel section were varied to understand their impact on the bridge’s seismic performance. In addition to the I-shape sections, a crossed two-I-shape section was also studied. Spectral analysis, nonlinear pushover analysis and nonlinear time-history analysis was performed on the bridge models in order to better understand the seismic performance of the studied bridge piers. Simulation results indicate that larger flanges increase the pier’s bending moment capacity, allowing it to absorb greater seismic energy and undergo larger deformations without failing. This increases the overall ductility of the pier and enhances its ability to dissipate seismic energy. However, excessively large flanges or web can reduce the concrete cover and reduce the durability of the pier in the context of Canadian extreme-winter conditions. The study concludes that a balance between web thickness and flange width must be achieved to ensure the bridge can resist seismic forces while maintaining sufficient ductility and energy dissipation. Therefore, an optimized design, according to seismic demands, enhances the overall resistance of CES bridge piers. Full article

Optimizing energy-intensive manufacturing under time-varying electricity tariffs requires scheduling strategies that reduce cost without compromising operational feasibility. This study is grounded in readily available industrial sensing: we exclusively use time-series measurements of aggregated active power and energy at the main distribution board of a quicklime production plant. We propose a tariff-aware load-shifting framework in which a Proximal Policy Optimization (PPO) reinforcement learning agent is trained in a custom Gymnasium environment to apply discrete consumption scaling actions constrained to 80–125% of a baseline profile during the operating shift (08:00–16:00), explicitly accounting for demand-charge exposure in the TOU peak window (13:00–15:00). The reward design combines instantaneous electricity cost with cumulative energy-tracking penalties and terms associated with operational constraints. Multi-day validation over $N=30$ working days shows consistent economic benefits, with a median total cost reduction on the order of 10% (narrow IQR) driven by reduced peak-window energy and demand peaks. However, the script-based binary compliance indicators (viol_energy, viol_prod_min) reveal deviations from the energy-balance criterion and occasional minimum-production shortfalls under the tolerances used, highlighting the cost–production trade-off and the need for stricter constraint handling for industrial deployment. In addition, we benchmark against dynamic programming (DP), an alternative RL policy (DQN), and a greedy heuristic (GREEDY), comparing cost; operational performance; and, when applicable, computational efficiency, which positions PPO as a competitive alternative among the considered methods. Overall, this work demonstrates how learning-based decision making can be coupled with real-world industrial sensing infrastructures, providing a data-driven tariff-aware scheduling layer for industrial energy management under practical constraints. Full article

Plant-derived extracellular vesicles (PDEVs), engineered phytosomes, bioinspired polymeric plant-based nanoparticles (PBNPs), hybrid phyto-inorganic nanocomposites, green-synthesized metal nanoparticles, self-assembled nanoarchitectures, and multifunctional composites represent a rapidly advancing class of sustainable, nature-inspired nanocarriers. These platforms combine exceptional biocompatibility, negligible immunogenicity, and renewable sourcing with tunable drug loading, targeted delivery, and controlled release properties. This review synthesizes translational advances from 2020 to 2026, covering scalable isolation/bioprocessing (bioreactors, elicitation), multi-parametric physicochemical/multi-omics characterization, rational engineering/hybridization, and rigorous in vitro/in vivo assessments of uptake, biodistribution, pharmacokinetic (PK), and efficacy. Phytosomes and PBNPs markedly enhance oral bioavailability and targeted delivery of lipophilic phytochemicals, while PDEVs offer unique immunomodulatory, anti-inflammatory, and gene-regulatory activities. Hybrid and green-synthesized systems provide structural stability, redox modulation, and synergistic effects, and self-assembled/multifunctional composites address solubilization barriers with stimuli-responsive design. Early-phase human studies on grapefruit-, ginger-, turmeric-, and ginseng-derived PDEVs report excellent short-term safety, favorable PK, and preliminary bioactivity signals, with no observed immunogenicity or dose-limiting toxicities; however, these trials remain exploratory, constrained by small sample sizes and safety-focused endpoints. Despite challenges, including methodological heterogeneity, variable yields, long-term safety uncertainties (notably for inorganic hybrids), and regulatory ambiguities, emerging strategies such as clustered regularly interspaced short palindromic repeats (CRISPR)-engineered plant line; artificial-intelligence-driven process optimization; standardized guidelines, and integrated clinical, intellectual property, and commercialization frameworks are progressively addressing these barriers. Collectively, these advances position plant-derived nanocarriers as immunologically privileged, eco-friendly alternatives to synthetic and mammalian platforms, laying the foundation for a sustainable era of precision phytomedicine. Full article

The regularity of the catenary system and the stability of pantograph–catenary interaction are crucial for ensuring continuous and stable current collection quality in high-speed trains. Given that the dropper is a key suspension component within the catenary, the state of service integrity directly determines the regularity of, and dynamics within, the pantograph–catenary system. However, under long-term alternating loads and environmental influences, the dropper inevitably suffers damage due to strand fracture. The geometric regularity of the catenary is consequently disrupted, and the current collection quality of trains can deteriorate. While substantial efforts have been devoted to the study of pantograph–catenary dynamics under ideal or intact dropper conditions, research on current collection quality when the dropper has different types of damage remains insufficiently understood. This study focuses on the practical operational situation of high-speed railways, investigating the impact of dropper damage on current collection quality. Firstly, based on the pantograph–catenary parameters of an actual line, a dynamic model capable of simulating different types of dropper damage was built. Secondly, the current contact quality under various types of damage was explored in detail by several time-domain statistical features. Finally, within the typical speed range of 250 km/h to 350 km/h, the evolution of pantograph–catenary dynamic behavior under the combined effects of operating speed and dropper damage was analyzed, providing a theoretical basis for the reliable assessment of pantograph–catenary current collection quality and the formulation of stable operation and maintenance strategies. Full article

Implantable artificial kidneys represent a promising alternative for patients with end-stage renal disease (ESRD), aiming to overcome the limitations of conventional dialysis through the integration of microfluidic and electrokinetic technologies. In this study, we present a sawtooth electrode microfluidic chamber that achieves blood cell separation via negative dielectrophoresis at a record-low operating voltage of 1.4 V, representing a fivefold reduction compared with rectangular electrode designs and supporting potential integration into implantable artificial kidney systems. A microfluidic chip incorporating an asymmetric sawtooth electrode geometry was developed to enhance local electric field gradients while reducing power consumption. Device performance was investigated using COMSOL Multiphysics simulations. Response Surface Methodology (RSM) based on a Box–Behnken design was employed to optimize the number of teeth per unit length (N), sawtooth height (H), and applied voltage (V), while excitation frequency was fixed at 1 MHz and flow velocity was maintained constant at 0.1 µL·min⁻¹. Statistical analysis was conducted using analysis of variance (ANOVA) in Minitab (Version 27; Minitab, LLC, State College, PA, USA, 2024). The optimization model showed strong predictive capability (R² = 95.8%) and identified applied voltage (59.45% contribution) and sawtooth height (33%) as the dominant factors affecting separation efficiency, with a significant H × V interaction (p = 0.023). Comprehensive voltage-response mapping over the range of 0.8–4.0 V revealed four operational regimes, including a previously unreported high-voltage failure zone above 2.8 V, where electrothermal flow and electroporation degrade performance. Under physiological conductivity conditions, the optimized design maintained a separation efficiency of 78.3% at 1.4 V with a tip temperature rise of only 1.2 °C, while full recovery of performance was achieved at 2.2 V. Cell-specific separation efficiencies reached 97.3% for white blood cells, 95.8% for red blood cells, and 84.7% for platelets, reducing the downstream cellular load by 92.6%. These findings demonstrate that the proposed low-voltage, high-efficiency separation platform has strong potential as a cellular pre-filtration module in implantable artificial kidney systems and other lab-on-chip biomedical devices. Full article

Managed colonies of the Western honey bee, Apis mellifera, are essential to global food security by ensuring the pollination of a wide array of crops that are crucial for human consumption. However, substantial declines in managed honey bee populations have been reported worldwide, including in Australia, the United States and Europe. These losses have been attributed to the multifaceted interplay of stressors encompassing agrochemical impact, climate fluctuations, pathogens, suboptimal forage conditions, and habitat reduction. In particular, Paenibacillus larvae, the causative agent of American foulbrood (AFB), is one of the most destructive bacterial pathogens for honey bees due to its high transmissibility, environmental persistence, and capacity to cause complete colony collapse. Recurrent and widespread AFB outbreaks impose significant economic and biosecurity burdens on apiarists, exacerbating declines in pollination services and agricultural productivity. This review synthesises the current landscape of therapeutic strategies targeting AFB, including bacteriophage-based approaches, vaccine development, probiotics, and essential oils, and evaluate their reported field applications, efficacy, and practical limitations. Bacteriophages and immune-priming approaches show the greatest potential to reduce larval mortality and pathogen load, although their application is constrained by formulation stability, delivery challenges, and limited large-scale field validation. Probiotics and essential oils produce highly variable and inconsistent effectiveness under field conditions. Overall, these alternatives currently represent promising complementary tools rather than standalone treatments, underscoring the need for further investigation. Full article

Background: This study aimed, in U11 male football players, (i) to investigate the effects of an 8-week running-based HIIT or SSGs program on aerobic fitness, neuromuscular performance and internal load, and (ii) to compare training-induced changes in performance variables between training modalities. Methods: Sixteen U11 football players were randomly assigned to either the SSGs group (4 vs. 4 format, 5 × 3 min with 1 min of rest between bouts) or the HIIT group (5 × 3 min of 15 s running at 100% peak velocity (Vpeak) alternating with 15 s of recovery, and 1 min of rest between sets). The intervention period lasted 8 weeks. Aerobic fitness (Yo-Yo Intermittent Recovery Level 1 Children’s Test, YYIR1C), sprint time performance (10 m and 20 m sprints tests) and change-of-direction (COD) ability (Arrowhead Agility Test) were assessed before and after the intervention. Heart rate (HR) and rating of perceived exertion (RPE) were assessed as indices of internal load. Results: Both SSGs and running-based HIIT produced comparable improvements in YYIR1C distance, Vpeak (p < 0.05), with no significant change in the between-group difference. Neuromuscular gains occurred only after SSGs (p < 0.05), with similar 10 m sprint improvements between groups but superior 20 m gains for SSGs (p < 0.01). COD ability improved in both groups (p < 0.05), with broader enhancements following SSGs (p < 0.05). Finally, running-based HIIT elicited greater HRpeak and higher RPE than SSGs (p < 0.05) across most intervention weeks. Conclusions: In U11 male football players, both SSGs and running-based HIIT effectively improved aerobic fitness and COD performance. However, SSGs may offer additional benefits for sprint development with lower perceived psychological stress. Full article

Ammonia is one of the most important and widely produced basic chemicals worldwide. However, this highly toxic gas is also produced in livestock farming and a variety of industrial processes, posing a potential threat to humans, animals and the environment and also significantly contributing to the formation of persistent particulate matter. The aim of this project was to develop a textile-based adsorber material and to demonstrate a suitable test system for purifying ammonia-contaminated air from production-related sources using the example of pig fattening and PCB production. This aim was achieved through the wash-resistant immobilization of polyacrylic acid on a polyester needle felt at laboratory, pilot plant and industrial scales. In addition, various system concepts have been developed in which air or phosphoric acid can flow through the adsorber textile, whereby in the latter case, the phosphoric acid is both actively involved in ammonia adsorption and also serves to elute the bound ammonia, enabling continuous and low-maintenance operation. Concurrently, the high-quality inorganic fertilizer ammonium phosphate is produced. In summary, an efficient alternative to existing solutions for ammonia minimization has been developed, which is fundamentally characterized by its universal applicability in different load scenarios, including small mobile systems in production facilities with local ammonia pollution, in addition to scenarios for large-scale agricultural operations. Full article

Lignin nanoparticles (LNPs) offer sustainable alternatives to petroleum-derived nanofillers, yet their industrial application remains limited by poor dispersion control and trade-offs between loading, optical clarity, and mechanical performance. Here, we present a molecular architecture-driven design framework that systematically decouples polymer network physics from nanoparticle dispersion in poly(vinyl alcohol)/LNP nanocomposites. Through eco-friendly self-precipitation, we synthesize uniform LNPs with size tunability, overcoming persistent reproducibility challenges. Systematic investigation across PVA molecular weights and LNP loadings reveals entanglement-controlled dispersion behavior. Combined rheological and small-angle X-ray scattering analyses demonstrate that macroscopic suspension rheology is governed exclusively by polymer chain overlap, remaining invariant across LNP loadings. Conversely, the nanoscale LNP microstructural organization—ranging from depletion-driven clustering in weakly entangled networks to network-confinement stabilization in densely entangled systems—fundamentally dictates the film’s optical clarity and mechanical toughness. This rheology-microstructure decoupling establishes critical processing windows for industrial formulations, where polymer entanglement ensures suspension processability while the LNP dispersion state enables optical–mechanical tunability. The entangled network’s structure-filtering effect provides robust protocols for fabricating sustainable, transparent bio-composites suitable for packaging, optics, and functional films. Our quantitative composition–structure–performance framework advances fundamental understanding of entanglement-mediated interfacial phenomena while delivering practical design rules for next-generation sustainable bio-composites. Full article

Objective: The objective of this study was to evaluate the efficacy of a ropivacaine-loaded poloxamer 407 (P407)-based thermosensitive hydrogel applied at the subfascial site compared with a continuous local anesthetic delivery system using a catheter for postoperative pain control after cesarean section (CS), in combination with standard intravenous patient-controlled analgesia (IV-PCA). Methods: This single-center, prospective randomized controlled trial included 72 pregnant women undergoing CS between April and October 2025. Participants were randomly assigned to receive either ropivacaine hydrogel or catheter-based ropivacaine infusion, both in conjunction with IV-PCA. Primary outcomes included numeric rating scale (NRS) pain scores at 3, 6, 12, 24, and 48 h postoperatively. Secondary outcomes included the time to first NSAID request and the cumulative use of rescue NSAIDs. Results: There were no significant differences in baseline characteristics between the groups. NRS pain scores did not differ significantly at any time point, although they varied significantly over time within each group. The hydrogel group showed a statistically significant delay in the time to first NSAID request (6.3 ± 5.1 h vs. 5.0 ± 6.1 h, p = 0.049) and higher cumulative NSAID use (2.4 ± 1.7 vs. 1.6 ± 1.2, p = 0.035). No serious complications were observed in either group. Conclusion: The ropivacaine hydrogel provided postoperative pain control comparable to that of the continuous catheter system, with no statistically significant differences in NRS scores observed between groups. Given its ease of use, absence of catheter-related concerns, and substantially lower total anesthetic dose, the P407-based hydrogel may represent a practical and patient-friendly alternative for post-cesarean analgesia. Full article