Search Results (6,299)

The escalating production of fetal bovine serum generates substantial quantities of fetal bovine hide as an underutilized byproduct. In this study, we extracted collagen from this source, characterized it as predominantly type I collagen with intact triple-helical features, and fabricated a series of composite sponge dressings by blending it with chitosan. The best-balanced formulation (COL₁/CS₁, 1:1 ratio) exhibited markedly superior physicochemical properties relative to pure collagen sponges, as evidenced by higher porosity (91.3%), water uptake (2010%), moisture retention (23.7%), and water vapor transmission rate (4169.02 ± 86.45 g/m²/day). We hypothesize that the intrinsically lower cross-linking density of fetal collagen may expose a greater abundance of carboxyl and hydroxyl moieties, thereby fostering electrostatic complexation and hydrogen bonding with chitosan’s amino groups. This molecular interplay appears to promote the genesis of a highly uniform, interconnective porous network. In vitro, the COL₁/CS₁ sponge elicited a hemolysis rate below 5%, a blood coagulation index as low as 7.02%, no cytotoxicity toward L929 and MRC-5 cells, and a pronounced capacity to stimulate cell proliferation and wound repopulation. In a murine full-thickness excisional wound model, the COL₁/CS₁ group achieved a 98.1% closure rate by day 14, significantly outpacing both the pure collagen and untreated controls. Histological examinations corroborated these findings, revealing accelerated granulation tissue deposition, robust neovascularization, and orderly collagen remodeling, with no overt toxicity observed in vital organs under the tested conditions. This work presents a viable valorization pathway for an agricultural byproduct into high-value biomedical constructs and provides insights into how source-dependent collagen attributes may influence the functional performance of biomaterials. Full article

To enhance renewable energy accommodation and operational flexibility under high renewable energy penetration, this study proposes a multi-objective optimal capacity configuration method for an electricity–heat–hydrogen integrated energy system incorporating a reversible solid oxide cell (RSOC). First, considering the bidirectional electricity–hydrogen conversion capability and waste heat recovery of the RSOC, an electricity–heat–hydrogen multi-energy complementary system is constructed, and efficiency correction models are established for key energy conversion devices to characterize their part-load characteristics. Second, representative source–load scenarios are generated using Latin hypercube sampling and K-means clustering, and a multi-objective optimal capacity configuration model is formulated to minimize the annualized total cost and the wind and photovoltaic power curtailment rate. Finally, given the limitations of the non-dominated sorting genetic algorithm II (NSGA-II) in complex capacity configuration problems, such as premature convergence to local optima and insufficient population diversity, an adaptive crossover and mutation mechanism, a local search strategy, and a dynamic selection mechanism based on comprehensive crowding distance are introduced to improve its optimization performance. A balanced configuration scheme is then selected based on the knee point of the Pareto front obtained by the algorithm. Case-study results show that the Pareto solution set obtained by the improved NSGA-II (INSGA-II) has better overall quality than those obtained by NSGA-II and multi-objective particle swarm optimization (MOPSO). The resulting balanced configuration scheme has an annualized total cost of CNY 422.9 million and a wind and photovoltaic curtailment rate of 2.797%. The proposed method effectively coordinates system economic performance and renewable energy accommodation, enhances the coordinated utilization of electricity, heat, and hydrogen energy flows, and provides a reference for capacity planning of integrated energy systems under high renewable energy penetration. Full article

This review systematically elucidates the rapidly evolving field of biomimetic coacervate coatings, bridging the fundamental thermodynamic principles of liquid–liquid phase separation (LLPS) with advanced biomedical translations. While conventional surface modifications for medical implants frequently fail to maintain structural and functional integrity within dynamic, wet physiological environments, biomimetic coacervation inspired by natural underwater adhesive mechanisms offers a highly versatile, conformable, and robust interfacial strategy. Here, we analyze the critical physicochemical driving forces governing coacervate formation, emphasizing the synergistic interplay of electrostatic, hydrophobic, hydrogen-bonding, and cation–$\pi$ interactions. We comprehensively discuss diverse macromolecular design principles utilizing marine-derived biopolymers, synthetic or recombinant polypeptides, and hybrid organic–inorganic condensates, alongside key architectural orchestration methodologies including direct deposition, in situ triggerable coacervation, and layer-by-layer (LbL) assembly. Furthermore, we evaluate multi-functional clinical translations, highlighting breakthroughs in wet tissue sealing, bone repair, localized stimuli-responsive drug or nucleic acid delivery, anti-biofouling medical device coatings, and regenerative cell–material interfaces. Ultimately, this review underscores the profound potential of biomimetic coacervates as a cornerstone platform for next-generation multifunctional medical devices and personalized regenerative medicine. Full article

Background/Objectives: Thrombotic cardiovascular diseases remain a major cause of morbidity and mortality worldwide. Current antithrombotic therapies are limited by insufficient thrombus targeting. This study aimed to develop a fibrin-binding peptide-functionalized, hydrogen peroxide (H₂O₂)-responsive polymeric micelle and to evaluate its physicochemical properties and biological effects under H₂O₂-induced endothelial oxidative stress and preliminary FeCl₃-induced thrombosis conditions. Methods: A fibrin-binding peptide, P2 (VTFIKC), was screened using computer-aided drug design and evaluated through microscale thermophoresis and in vitro thrombus adhesion assays. An all-trans retinoic acid (atRA)-based boronate ester prodrug, BORA, was synthesized to enable H₂O₂-triggered degradation and drug release. BORA was co-assembled with P2-modified Mal-PEG-b-PAsp to prepare P2-Mal-PEG-b-PAsp/BORA micelles. Their physicochemical properties, H₂O₂ responsiveness, H₂O₂-scavenging activity, cytocompatibility, cytoprotective effects, anti-inflammatory activity, and preliminary in vivo efficacy were evaluated. Results: The resulting micelles exhibited a suitable nanoscale size, acceptable cytocompatibility, H₂O₂-responsive changes in particle size distribution, and concentration-dependent H₂O₂-scavenging activity. In H₂O₂-stimulated human umbilical vein endothelial cells, micelle treatment was associated with improved cell viability, lower intracellular ROS-associated fluorescence, and reduced TNF-α and IL-1β concentrations. In a FeCl₃-induced rat carotid artery thrombosis model, P2-Mal-PEG-b-PAsp/BORA micelles altered platelet- and leukocyte-related hematological indices and exhibited preferential accumulation in the thrombotic carotid artery. Conclusions: P2-Mal-PEG-b-PAsp/BORA micelles combine P2-mediated fibrin-binding potential, H₂O₂-responsive release behavior, and H₂O₂-scavenging activity. The findings provide preliminary support for further investigation of this peptide-functionalized nanoplatform. Full article

Zeolitic imidazolate framework-8 (ZIF-8) has emerged as a material for electrochemical energy conversion, serving dual primary roles in fuel cell technologies: (i) as an electrocatalyst precursor for oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) through pyrolysis-derived N-doped porous carbons and metal–nitrogen–carbon (M–N–C) structures, and (ii) as a membrane component that enhances proton conductivity via imidazole-mediated Grotthuss hopping while suppressing fuel crossover through molecular sieving. This comprehensive review systematically evaluates ZIF-8 performance across multiple fuel cell types, including primarily proton exchange membrane fuel cells (PEMFCs), as well as direct methanol fuel cells (DMFCs), anion exchange membrane fuel cells (AEMFCs), and microbial fuel cells (MFCs), while also covering related electrochemical applications such as zinc–air batteries, supercapacitors, and water splitting devices, where ZIF-8-derived materials demonstrate improved catalytic activity. The review examines structure–performance relationships, highlighting strategies such as heteroatom doping, bimetallic synergy, hierarchical porosity engineering, and polymer composite fabrication that have enabled ZIF-8-based catalysts to achieve ORR half-wave potentials and PEMFC power densities, rivaling commercial Pt/C systems. ZIF-8 composite membranes demonstrate proton conductivities in polybenzimidazole systems and effective methanol blocking. Despite improved progress, challenges persist regarding long-term stability, scalable synthesis, and degradation mechanism understanding. This review critically analyzes recent advances, identifies performance-limiting factors across applications, and outlines future research directions for developing commercially viable ZIF-8-based electrochemical technologies. Full article

Background: The vaginal microbiota of healthy women is predominantly composed of lactic acid bacteria (LAB), particularly species from the lactobacilli group, which contribute to the maintenance of vaginal health through multiple protective mechanisms. Objectives: In the present study, vaginal LAB isolated from healthy premenopausal Algerian women were evaluated for their probiotic potential. Methods: A total of 259 LAB isolates were initially screened for antimicrobial activity against vaginal pathogens, among which 164 strains exhibited inhibitory effects. Based on antimicrobial capacity and biofilm formation ability, 38 strains were selected for further characterization. A refined subset of 15 strains belonging to Lactiplantibacillus (Lpb.) plantarum, Limosilactobacillus (Lmb.) fermentum, and Ligilactobacillus (Lgb.) salivarius were subsequently identified according to their superior antimicrobial and probiotic-related properties. The selected strains were evaluated for several functional and safety characteristics, including antimicrobial activity, production of lactic acid and hydrogen peroxide (H₂O₂), biofilm formation, auto-aggregation, cell surface hydrophobicity, antibiotic susceptibility, hemolytic activity, and tolerance to acidic conditions. These studies were complemented with comparative genomics using the complete genome sequences of selected strains. Results: The isolates demonstrated significant inhibitory activity against vaginal pathogens associated with aerobic vaginitis, and vulvovaginal candidiasis. In addition, strong correlations were observed between metabolite production and antimicrobial activity. Several strains also exhibited enhanced biofilm formation, aggregation capacity, and favorable safety profiles. Among the tested isolates, Lmb. fermentum 70BJ2, Lpb. plantarum 87JG8, and Lpb.plantarum N17 emerged as particularly promising probiotic candidates due to their combined antimicrobial, metabolic, and adhesion-related properties. Conclusions: Overall, these findings demonstrate that the vaginal microbiota of healthy Algerian women represents a valuable source of potential probiotic strains and provide a strong basis for future in vivo validation and clinical application in the prevention and management of vaginal infections. Full article

Oxidative stress is strongly associated with neuronal damage in neurodegenerative diseases, such as Parkinson’s disease (PD). Fungal melanins are remarkable free radical scavengers; however, their capacity to protect neurons from reactive oxygen species (ROS)-induced damage remains understudied. This research evaluated the neuroprotective effects of fungal melanins and their arginine-modified counterparts on SH-SY5Y cells against neurotoxins, as well as their impact on ROS levels. Exposure to 0.6 mM H₂O₂ or 1 mM MPP⁺ markedly elevated ROS levels and reduced cell viability to approximately 56% and 60%, respectively. At 10 μg/mL, melanins from Apioperdon pyriforme, Russula nigricans, and Xylaria nigripes significantly protected cells against H₂O₂ cytotoxicity, whereas arginine-modified melanin from the skin of Scleroderma sinnamariense significantly attenuated MPP⁺ cytotoxicity. Further dose-dependent evaluation revealed that melanin from A. pyriforme (10–12 μg/mL) displayed activity comparable to the positive control (164 μg/mL N-Acetylcysteine (NAC)) against H₂O₂ by increasing cell viability up to 90%. Similarly, arginine-modified melanin from S. sinnamariense (6–10 μg/mL) and NAC showed a comparable protective effect against MPP⁺, boosting cell viability up to 80%. Both samples suppressed ROS to levels comparable to, or lower than, the untreated control. Melanin from A. pyriforme is a promising candidate for further research into complementary therapies for PD. Full article

Astrocyte senescence is a recognized feature of brain aging, but its impact on neuronal mitochondrial homeostasis remains poorly defined, particularly in human cells. Here we show that doxorubicin-induced senescence disrupts mitochondrial function in primary human astrocytes and compromises their capacity to sustain neuronal bioenergetics. Senescent astrocytes accumulated a denser population of smaller, ultrastructurally damaged mitochondria together with increased levels of fission, fusion and biogenesis-associated proteins. Despite this apparent expansion of the mitochondrial compartment, these cells displayed reduced mitochondrial membrane potential, intracellular ATP and cellular metabolic activity, indicating accumulation of a functionally impaired mitochondrial population. Senescence also remodeled the extracellular mitochondrial compartment: conditioned medium from senescent astrocytes contained fewer mitochondrial particles with lower membrane potential and reduced ATP. Functionally, conditioned medium from control astrocytes increased TOMM20 and PGC-1α levels in human postmitotic neurons, whereas medium from senescent astrocytes failed to elicit this response and instead promoted hydrogen peroxide accumulation, ATP depletion and reduced cellular metabolic activity in the absence of overt cytotoxicity. Neurons acquired an astrocyte-derived MitoTracker signal from both conditions. Our data indicate that factors released by senescent human astrocytes are sufficient to induce neuronal mitochondrial and redox dysfunction. Full article

Electric–hydrogen hybrid microgrids integrating distributed renewables with electrolysers can efficiently convert dispersed renewables into hydrogen, meeting local electricity demands. However, intermittent and uncertain renewables together with sudden load changes can cause severe bus voltage fluctuations and degrade power quality, especially in off-grid microgrids. Furthermore, the electrolyser’s auxiliary units require stable AC power supply even during fault events, which most likely occur at AC–DC converters. To ensure stability during renewable/load fluctuations and converter faults, this paper proposes a fault-resilient coordinated voltage control scheme by combining PI with piecewise active disturbance rejection control to mitigate DC bus voltage fluctuations during transient disturbances and regulates AC-side fuel cells via control switching to stabilise AC voltage after the complete disconnection converter fault. The scheme is tested using a simulated kW-scale electric–hydrogen hybrid microgrid in various operating scenarios and compared with conventional methods that combine PI with PI or linear active disturbance rejection control. The simulation results show that the proposed control scheme improves DC bus voltage stability by 14% during transient renewable/load fluctuations via the incorporation of PADRC and enhance system resilience against AC–DC converter faults through the synergy of batteries and fuel cells, which construct the voltage (and frequency) of DC and AC buses, respectively. Full article

Glioblastoma (GBM) frequently recurs after temozolomide (TMZ) therapy and exhibits substantial redox plasticity. Our previous work showed that the effects of hydrogen peroxide (H₂O₂) vary with its level and between parental and TMZ-resistant GBM cells. Succinate dehydrogenase subunit D (SDHD), a membrane-anchoring component of mitochondrial complex II, is positioned at the interface of electron transport and redox homeostasis, but its regulation in GBM remains unclear. We therefore examined whether SDHD expression changes across distinct H₂O₂-responsive contexts involving aquaporins (AQPs) and AKT. TCGA transcriptomic analysis showed higher SDHD mRNA expression in WHO grade IV than in grade II/III gliomas, whereas paired primary/recurrent high-grade glioma samples showed heterogeneous SDHD changes at recurrence. TMZ reduced SDHD, and SDHD knockdown decreased intracellular reactive oxygen species. Combined redox perturbation reduced SDHD, whereas AKT inhibition restored SDHD expression. Under receptor-associated signaling conditions, EGFRvIII expression or CXCL12 stimulation increased measured H₂O₂ together with AQP3, AKT Ser473 phosphorylation, and SDHD. In TMZ-resistant cells, pharmacological perturbation of aquaporin-associated signaling decreased AQP9 together with AKT Ser473 phosphorylation and SDHD. An AQP3-targeting compound further reduced cell density when combined with TMZ. Together, these findings suggest that changes in SDHD expression are consistent with a compensatory redox response in GBM cells and that its regulation varies with the nature of H₂O₂-associated signaling during TMZ-related stress. Full article

In grid-connected smart integrated energy systems with high shares of renewable generation, source-side variability and inadequate coordination among battery storage, other energy carriers, and the external grid limit local renewable-electricity utilization and impede deep decarbonization. This study proposes a machine-learning-assisted, renewable-driven framework for multi-energy coupling and scenario-based multi-objective optimization of electricity–heat–hydrogen–storage systems. Historical meteorological and load data are processed using K-means clustering and Latin hypercube sampling to construct representative operating scenarios across multiple volatility regimes and characterize source–load uncertainty. The equipment model includes photovoltaic arrays, wind turbines, heat pumps, electrolyzers, fuel cells, grid-interactive battery energy storage, thermal storage, and hydrogen storage; cross-carrier conversion dynamics and emissions from purchased electricity and natural gas are embedded in the energy-balance constraints. A mixed-integer linear programming formulation then co-optimizes battery charging and discharging, grid exchange, and other multi-energy flows with respect to operating cost, carbon emissions, and renewable-energy curtailment. At 95% renewable-energy penetration, the proposed method achieves a renewable-energy absorption rate of 91.6% and a curtailment rate of 8.4%. Across the carbon-price cases, annualized operating cost ranges from 126.5 × 10⁴ to 141.2 × 10⁴ USD yr⁻¹, while carbon-emission intensity ranges from 26.4 to 38.5 gCO₂/kWh_eq. Under the specified high-risk grid disturbances, the coordinated strategy limits load shedding to 1.8%—73% below deterministic scheduling and 79% below the heuristic benchmark—and maintains 92.6% hydrogen self-sufficiency. These results provide a data-driven modeling and decision framework for battery–grid coordination and deep decarbonization in smart integrated energy systems. Full article

The deployment of hydrogen-powered public transport requires operators to decide not only whether to adopt fuel-cell buses, but also how hydrogen should be supplied. This study compares two sourcing strategies, as follows: on-site hydrogen production (Make) and external procurement (Buy). An operator-centered framework combining Levelized Cost of Hydrogen (LCOH) and Total Cost of Ownership (TCO) is applied to two Italian cases, using project-specific procurement and technical data from Monfalcone/Gorizia and Ferrara together with explicit modeling assumptions. Under base-case assumptions, Make yields an LCOH of €13.67/kg H₂ and a fleet TCO of €2.34/km, compared with €2.51/km for Buy at a delivered green hydrogen price of €12/kg. The deterministic break-even price is €10.25/kg, while both hydrogen configurations remain more expensive than diesel (€1.24/km). A probabilistic analysis based on 10,000 Latin Hypercube simulations and six uncertain parameters shows that Make is less costly in 78.8% of cases and Buy in 21.2%. The median probabilistic break-even price is €10.38/kg, with a 5th–95th percentile range of €8.79–12.38/kg. Delivered hydrogen price is the main driver, followed by Make CAPEX, fleet utilization, and financing conditions. Hydrogen sourcing therefore remains a strategic investment choice, with implications for capital exposure, renewable-energy integration, economic sustainability, and supply resilience. Full article

Global warming is increasing the frequency of acute temperature fluctuations that may threaten ectothermic reptiles, but the underlying physiological and cellular mechanisms remain poorly understood. This study investigated physiological changes, oxidative imbalance, antioxidant systems, nitric oxide, iron metabolism, and red blood cell morphology in butterfly lizards (Leiolepis belliana belliana) under acute temperature elevation. Physiological responses were evaluated in vivo in butterfly lizards exposed to temperatures of 27–37 °C, whereas biochemical responses in red blood cells were examined in vitro at 27–39 °C, and red blood cell morphology was evaluated at 27–37 °C. Body temperature (p = 0.00000107) and pulse rate (p = 0.00000147) increased significantly with increasing temperature, whereas respiratory rate (p = 0.4185) and blood oxygen saturation (p = 0.7672) were not significantly affected. In blood cells, cellular metabolic activity (p = 0.00000674), malondialdehyde (p = 0.000256), protein oxidation (p = 0.0000526), ferric iron (p = 0.000000105), and vitamin E (p = 0.000464) increased significantly, whereas total antioxidant capacity (p = 0.0000000896), glutathione (p = 0.000453), nitric oxide (p = 0.000000252), and ferrous iron (p = 0.0000000182) decreased significantly. Hydrogen peroxide (p = 0.000181), glutathione peroxidase activity (p = 0.000000169), and catalase activity (p = 0.00000182) also showed significant temperature-dependent changes. Red blood cell elongation increased significantly (p = 0.0005), whereas nucleus size remained unchanged (nucleus length, p = 0.6800; nucleus width, p = 0.8814). Acute temperature elevation increased cellular metabolic activity and was accompanied by impaired antioxidant defense, oxidative damage, disruption of nitric oxide homeostasis, and iron dysregulation in butterfly lizard red blood cells. These findings improve our understanding of the cellular mechanisms underlying acute heat stress in ectothermic reptiles. Full article

Solid oxide electrolysis cells (SOECs) are promising devices for high-efficiency hydrogen production using variable renewable energy. However, dynamic operation involves complex interactions among electrochemical heat generation or absorption, gas heat transfer, temperature-dependent cell voltage, and thermal inertia of stack components. Therefore, mechanical reliability should be evaluated together with load-following performance. In this study, a transient stress analysis framework was developed for an SOEC stack by coupling a transient temperature distribution model, finite element stress analysis, and a surrogate model. The temperature model considers the active cell region, inactive cell region, and edge region, and calculates the evolution of in-plane temperature distributions during power fluctuations. The obtained temperature fields were transferred to finite element stress analysis to evaluate the stress states of the YSZ electrolyte, Ni-YSZ hydrogen-electrode support, and metal interconnector. To enable long-duration evaluation, a surrogate model was constructed from finite element results and applied to time-series temperature distributions under dynamic operating conditions. The suggested framework enables efficient estimation of transient stress histories and clarifies how temperature gradients formed during load changes affect stack components. This approach provides a useful basis for assessing mechanical reliability and designing operating strategies for SOEC stacks coupled with variable renewable energy. Full article

Lithium-ion batteries are widely used in electric mobility, renewable energy integration, portable electronics, and renewable–hydrogen hybrid energy systems. Despite significant advances in battery materials and design, long-term degradation remains a major challenge that affects system reliability, efficiency, and economic viability. In renewable–hydrogen hybrid architectures, battery degradation influences not only energy storage performance but also hydrogen production stability, electrolyzer operation, fuel cell utilization, and overall system efficiency. Major degradation mechanisms include solid electrolyte interphase (SEI) growth, electrolyte decomposition, lithium inventory loss, transition-metal dissolution, particle cracking, and structural phase transformations. This review provides a comprehensive assessment of degradation mechanisms affecting lithium-ion battery components and their implications for renewable–hydrogen hybrid systems. Advanced characterization techniques, including in situ and operando X-ray diffraction, electron microscopy, spectroscopy, electrochemical impedance spectroscopy, cyclic voltammetry, and differential capacity analysis, are examined for their ability to reveal chemical, structural, and morphological changes during battery operation. Particular emphasis is placed on the effects of dynamic load variations, partial state-of-charge cycling, temperature fluctuations, and intermittent renewable energy inputs that accelerate degradation in hybrid systems. The review further discusses mitigation strategies such as surface engineering, electrolyte optimization, material doping, thermal management, intelligent energy management systems, predictive maintenance, and machine learning-based prognostics. Key challenges associated with battery–hydrogen integration, including efficiency trade-offs, component ageing, hydrogen production stability, and lifecycle costs, are critically analysed. The adaptability of hybrid systems under varying operating conditions is also explored, highlighting the importance of degradation-aware control strategies, digital twins, and real-time diagnostics. Finally, future research directions are identified, including multiscale characterization, physics-informed machine learning, techno-economic optimization, and life-synergy modelling. These approaches are essential for developing reliable, adaptive, and cost-effective renewable–hydrogen hybrid energy systems capable of supporting long-term decarbonization objectives. Full article