Search Results (1,462)

Electroactive biofilms (EABs) are essential for the performance of bioelectrochemical systems (BESs), but their formation in Geobacter, critically on conductive pili and exopolysaccharides, limits application under conditions where these components are deficient. Herein, we investigated the restorative effects of exogenous flavin mononucleotide (FMN) on EAB formation and extracellular electron transfer (EET) in two defective mutants of Geobacter sulfurreducens: the pili-deficient PCAΔ1496 and exopolysaccharides-deficient PCAΔ1501. Results show that FMN significantly promoted biofilm thickness in PCAΔ1496 (250%) and PCAΔ1501 (33%), while boosting maximum current outputs by 175-fold and 317.7%, respectively. Spectroscopic and electrochemical analyses revealed that FMN incorporates into biofilms, binds to outer membrane c-type cytochromes (c-Cyts), and enhances electron exchange capacity. Differential pulse voltammetry further confirmed that FMN did not exist independently in the biofilm but bound to outer membrane c-Cyts as a cofactor. Collectively, exogenous FMN plays dual roles (electron shuttle and cytochrome-bound cofactor) in defective Geobacter EABs, effectively restoring biofilm formation and enhancing EET efficiency. This study expands the understanding of the formation mechanism of Geobacter EABs and provides a novel strategy for optimizing BES performance. Full article

With the acceleration of industrialization, the problems of water resource pollution and shortage caused by oil spills and industrial wastewater discharge have become increasingly severe, posing a major threat to ecological sustainable development. Therefore, efficient oil–water separation technology has become a key breakthrough to alleviate this crisis. In this study, Janus membranes with asymmetric wettability were prepared by layer-by-layer electrospinning. The influence of the thickness ratio between the hydrophobic layer and the hydrophilic layer on the mechanical properties, separation flux, and oil–water mixture efficiency of the Janus membranes was examined, and an optimized membrane configuration was determined: the optimal thickness ratio between hydrophobic and hydrophilic layers was 4:6. Under these conditions, the fracture stress of the fiber membranes reached 99% MPa, the fracture strain was 55.63 ± 4.77%, the separation flux values were 1888.22 and 1042.66 L m⁻² h⁻¹ for the oil–water mixture and water-in-oil emulsion, respectively, with the separation efficiencies all exceeding 99%. After 50 cycles of separation for two different oil-in-water emulsions, the separation flux and separation efficiency of the optimal sample remained relatively stable, demonstrating strong practicability. In general, the Janus fiber membranes met the expected requirements, laying a good foundation for future applications in oil–water separation, floating oil collection in water, and other fields. Full article

This pilot study assessed the effectiveness of the intravitreal dexamethasone implant (Ozurdex) in retinal vein occlusion (RVO) patients and explored potential pre-treatment biomarkers to improve management and prognosis. Eighteen patients with branch RVO (BRVO) and twenty-four with central RVO (CRVO) receiving two intravitreal injections of Ozurdex (at baseline and between 4 and 6 months) were included. Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were recorded at baseline and after 3, 6, and 12 months. Retinal morphology was assessed using optical coherence tomography (OCT), and serum biomarkers were analyzed by ELISAs. No significant BCVA improvement was observed in RVO patients, while CRT significantly decreased from 3 to 12 months. Patients without defects of the retinal inner layers, ellipsoid zone, and external limiting membrane showed significantly higher BCVA at 6 and 12 months. Both BRVO and CRVO groups demonstrated significant BCVA improvement and CRT reduction at 6 and 12 months, with better outcomes in BRVO patients. These patients exhibited lower baseline serum levels of xanthine oxidase (XO) and thrombospondin-1 (TSP-1), which inversely correlated with BCVA at 12 months. Ozurdex was effective in real-life RVO treatment, particularly in BRVO. Serum XO and TSP-1 may serve as prognostic biomarkers for RVO. Full article

Sluggish oxygen reduction reaction (ORR) remains a critical barrier to advancing intermediate-temperature electrochemical energy devices. Here, we demonstrate that strain engineering in two platforms, epitaxial thin films and freestanding membranes, systematically tunes ORR kinetics in Ruddlesden-Popper LaSrCoO₄. In epitaxial films, film thickness is varied to control in-plane tensile strain, whereas in freestanding membranes strain relaxation during the release step using water-soluble sacrificial layers produces flat or wrinkled architectures. Electrochemical impedance spectroscopy analysis reveals more than an order of magnitude increase in the oxygen surface exchange coefficient for tensile-strained films relative to relaxed films, together with a larger oxygen vacancy concentration. Wrinkled freestanding membranes provide a further increase in oxygen surface exchange kinetics and a lower activation energy, which are attributed to increased active surface area and local strain variation. These results identify epitaxial tensile strain and controlled wrinkling as practical design parameters for optimizing ORR activity in Ruddlesden-Popper oxides. Full article

We investigate optical bistability (OB) in a hybrid system comprising a semiconductor quantum dot (SQD), a metallic nanoshell (MNS), and a cell membrane within the framework of the multipole approximation. Bistability phase diagrams plotted in the system’s parameter subspaces demonstrate that, in the weak exciton–phonon coupling regime, dynamic switching of bistable states among no-channel, single-channel, and dual-channel configurations can be achieved via precise modulation of the MNS’s dielectric shell thickness. Especially, a critical sensing threshold is identified: the absorption peak disappears and a bistable effect emerges when only 1.82% of normal cells undergo malignant transformation. Furthermore, the bistable region exhibits a gradual broadening trend with an increasing proportion of cancerous cells, yielding a quantitative and ultra-sensitive readout that underpins a highly accurate strategy for early cancer diagnosis. These findings not only deepen our fundamental understanding of bistability regulation in hybrid quantum-plasmonic systems interfaced with biological materials but also offer valuable insights for the development of next-generation optical switches and biomedical sensing platforms. Full article

Background: Autologous platelet concentrates, including platelet-rich fibrin (PRF) matrices, have been proposed as biologically active scaffolds for vital pulp therapy. Evidence on the clinical use of different solid PRF matrices for direct pulp capping remains limited. Objective: The aim of this study is to describe and monitor two clinical cases of reversible pulpitis treated with direct pulp capping using two PRF membranes prepared by different centrifugation approaches, namely advanced platelet-rich fibrin plus (A-PRF+) and horizontal platelet-rich fibrin plus (H-PRF). Methods: In Case 1, A-PRF+ was prepared using a fixed-angle centrifugation protocol; in Case 2, H-PRF was prepared using a horizontal centrifugation protocol. In both cases, deep carious lesions with small carious pulp exposures (<1.5 mm) were managed by caries removal, ozone-assisted dentin disinfection, and direct pulp capping with the respective PRF membrane, followed by temporary calcium-silicate cement definitive coronal restoration. Clinical and radiographic follow-up, including cone-beam computed tomography, was performed for up to 12 months. Results: In Case 1 (A-PRF+), reparative dentin bridge formation was confirmed at 90 days, with a thickness of 0.2 mm. In Case 2 (H-PRF), reparative dentin was observed within 46 days, with a thickness of 0.28 mm. In both cases, pulp vitality was maintained, and no clinical symptoms or periapical changes were detected during the 12-month follow-up. Conclusions: These two cases suggest that direct pulp capping using PRF membranes (A-PRF+ or H-PRF), combined with ozone-assisted dentin disinfection and adequate coronal sealing, may be associated with maintained pulp vitality and hard-tissue repair after carious pulp exposure diagnosed as reversible pulpitis. Due to the descriptive two-case design and major confounding factors (including age and lesion characteristics), no comparative conclusions can be drawn. Prospective controlled clinical studies with standardized protocols are warranted. Full article

Background: Extended platelet-rich fibrin (e-PRF) membranes are a novel 100% autologous biomaterial with a longer resorption time (4–6 months) than traditional solid-PRF membranes (two weeks). In part 1 of this 2-part publication series, four clinical variations for using these novel e-PRF membranes for socket preservation were introduced. In this randomized clinical trial (RCT), all four iterations of e-PRF membranes were compared to traditional collagen membranes in alveolar ridge preservation for hard and soft tissue dimensional changes and early wound healing outcomes. Methods: A single-center RCT was conducted, including 55 patients requiring the extraction of a single tooth with planned implant placement. All sockets were grafted with a “sticky bone” (bone allograft mixed with PRF) and secured with either a collagen membrane (control) or e-PRF membranes utilizing the four variations present in Part 1 (both formed extra-orally or intra-orally, each with or without an overlying solid PRF membrane). The time of fabrication and application of each e-PRF iteration was recorded. Cone beam computed tomography was utilized to evaluate horizontal and vertical ridge dimensions at baseline and 3 months post-operatively, and soft tissue thickness was also measured at both time intervals utilizing an endodontic reamer. Early wound healing was recorded at 2 weeks, utilizing the Landry, Turnbull, and Howley Index by three blinded clinicians. Results: The results demonstrated that, at 3 months, the e-PRF membranes fabricated utilizing all 4 treatment variations demonstrated equal improvements in horizontal and vertical ridge dimensions and soft tissue thickness when compared to collagen membranes. Additionally, the membrane (p = 0.029) and membrane w/solid (p = 0.021) groups demonstrated statistically significant superior early wound healing compared to the collagen membrane group. Notably, the Bio-Filler groups demonstrated statistically significant reduction in fabrication/application time compared to the membrane groups. Conclusions: Within the limitations of this RCT, all e-PRF iterations performed comparably to collagen membranes in maintaining both hard and soft tissue ridge dimensions when combined with sticky bone, while also significantly improving soft tissue wound healing. Future RCTs with alternative grafting materials, direct wound-margin assessment, and evaluation of patient-reported outcomes are necessary to clarify the advantages of each membrane type. Full article

Background/Objectives: Ocular graft-versus-host disease (oGVHD) is a chronic, immune-mediated complication of allogeneic hematopoietic stem cell transplantation that can progress to corneal ulceration or perforation. These cases are often refractory to standard therapy and present a high risk of graft failure after keratoplasty. We report a case of oGVHD-related corneal perforation successfully managed with a novel amniotic membrane-assisted “envelope” technique during corneal transplantation. Case Report: A 42-year-old man with chronic oGVHD and a full-thickness corneal perforation underwent urgent repair with a lamellar patch graft completely wrapped in cryopreserved amniotic membrane, followed by penetrating keratoplasty (PKP) using an amniotic membrane envelope surrounding the donor lenticule. Results: The amniotic membrane provided a 360° biological barrier that isolated graft antigens from the inflammatory environment while supporting epithelial healing and stromal remodeling. Despite recurrent inflammatory episodes and multiple procedures—including cataract extraction, pars plana vitrectomy, and multilayer amniotic membrane transplantation—the graft remained clear and stable at 12-month follow-up, achieving a best-corrected visual acuity of 20/40. Conclusions: The amniotic membrane envelope technique may represent a valuable adjunct in managing high-risk corneal perforations secondary to oGVHD. By combining immune modulation and regenerative support, this approach can enhance tectonic stability, reduce rejection risk, and promote durable surface recovery, potentially delaying or avoiding keratoprosthesis in refractory cases. Full article

At present, conventional cold storage facilities in China are poorly suited to on-farm storage demands for agricultural produce, mainly due to their large spatial requirements, complex and labor-intensive installation procedures, limited portability, and insufficient coverage in rural areas. These limitations significantly contribute to post-harvest losses of perishable crops such as cherry tomatoes. To address this challenge, the present study proposes a compact and temporary cold storage system—gas-inflated membrane cold storage (GIMCS)—which exploits the inherent safety, cost-effectiveness, ease of deployment, and adaptability of inflatable membrane structures. A series of mechanical performance tests, including tensile strength, pressure resistance, and burst tests, were conducted on PA/PE (Polyamide/Polyethylene) composite membranes. The optimal configuration was identified as a membrane thickness of 70 μm, a gas column width of 2 cm, and a PA/PE composition ratio of 35%/65%. Thermal performance evaluations further revealed that filling the inflatable structure with 100% CO₂ yielded the most effective insulation. Through structural optimization, a cotton-filled gas-inflated membrane cold storage system (CF-GIMCS) incorporating a dual insulation strategy—combining intra-membrane and extra-membrane insulation—was developed. This multilayer configuration significantly reduced conductive and convective heat transfer, resulting in enhanced thermal performance. A comparative evaluation between GIMCS and a conventional cold storage system of equivalent capacity was conducted over a 15-day storage period, considering construction cost, temperature uniformity, and fruit preservation quality. The results showed that the construction cost of GIMCS was only 38% of that of conventional cold storage. The internal temperature distribution of GIMCS was highly uniform, with a maximum horizontal temperature difference of 1.4 °C, demonstrating thermal stability comparable to conventional systems. No statistically significant differences were observed between the two systems in key post-harvest quality indicators, including weight loss and respiration rate. Notably, GIMCS exhibited superior performance in maintaining fruit firmness, with a hardness of 1.30 kg·cm⁻² compared to 1.26 kg·cm⁻² in conventional storage, indicating a potential advantage in shelf-life extension. Overall, these findings demonstrate that GIMCS represents an affordable, technically robust, and portable cold storage solution capable of delivering preservation performance comparable to—or exceeding—that of conventional cold storage. Its modularity, mobility, and ease of relocation make it particularly well suited to the operational and economic constraints of smallholder farming systems, offering a practical and scalable pathway for improving on-farm cold chain infrastructure. Full article

Controlled-release systems must translate material design choices into predictable pharmacokinetic (PK) profiles, yet purely mechanistic or purely data-driven models often underperform when tuning complex polymer networks. Here, we develop tunable poly(vinyl formal) membranes (PVFMs) for diclofenac delivery and integrate classical kinetic analysis with a Generalized Regression Neural Network (GRNN) to connect formulation variables to release behavior and PK-relevant targets. PVFMs were synthesized across a gradient of crosslink densities by varying HCl content; diclofenac release was quantified under standardized conditions with geometry and dosing rigorously controlled (thickness, effective area, surface-area-to-volume ratio, and areal drug loading are reported to ensure reproducibility). Release profiles were fitted to Korsmeyer–Peppas, zero-order, first-order, Higuchi, and hyperbolic tangent models, while a GRNN was trained on material descriptors and time to predict cumulative release and flux, including out-of-sample conditions. Increasing crosslink density monotonically reduced swelling, areal release rate, and overall release efficiency (strong linear trends; r ≈ 0.99) and shifted transport from anomalous to Super Case II at the highest crosslinking. Classical models captured regime transitions but did not sustain high accuracy across the full design space; in contrast, the GRNN delivered superior predictive performance and generalized to conditions absent from training, enabling accurate interpolation/extrapolation of release trajectories. Beyond prior work, we provide a material-to-PK design map in which crosslinking, porosity/tortuosity, and hydrophobicity act as explicit “knobs” to shape burst, flux, and near-zero-order behavior, and we introduce a hybrid framework where mechanistic models guide interpretation while GRNN supplies robust, data-driven prediction for formulation selection. This integrated PVFM–GRNN approach supports rational design and quality control of controlled-release devices for diclofenac and is extendable to other therapeutics given appropriate descriptors and training data. Full article

Polymeric membranes based on chitosan (Cs) were extracted from shrimp shells and evaluated. These membranes were modified using polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), and glycerol (Gly) and crosslinked with glutaraldehyde (GA) to examine their suitability for water filtration processes. The Cs exhibited high purity, a total nitrogen content of 6.49%, and an average molecular weight of 456 kDa, all of which are suitable for membrane formation. Four membranes (Cs-GA, B2: Cs-PEG, B5: Cs-PEG-PVP, and B7: Cs-Gly) were characterized by means of FTIR, SEM, AFM, thickness, contact angle, tensile testing, TGA, DSC, and filtration with distilled water at 4.83 bar. B2 and B5 showed thicknesses of 207 and 190 μm and contact angles of 56.7° and 58.9°, lower than that of Cs-GA (89.4°). In filtration, B2 achieved a flux of 2222.70 LMH, a permeance of 460.19 LMH·bar⁻¹, and a hydraulic resistance of 8.79 × 10¹¹ m⁻¹, while Cs-GA, B5, and B7 exhibited fluxes of 24.10, 40.43, and 24.77 LMH, respectively, permeances of 9.75, 8.37, and 5.13 LMH·bar⁻¹, and hydraulic resistances of 4.15 × 10¹³, 4.83 × 10¹³, and 7.89 × 10¹³ m⁻¹, in the same order. Overall, membranes B2 and B5 are recognized as the most promising for water filtration under pressured operating conditions. Full article

Photocatalytic water sterilization has emerged as a promising sustainable technology for addressing microbial contamination across diverse sectors including healthcare, food production, and environmental management. This review examines the fundamental mechanisms and recent advances in photocatalytic water sterilization, with a particular emphasis on the differential bactericidal pathways against Gram-negative and Gram-positive bacteria. Gram-negative bacteria undergo a two-step inactivation process involving initial outer membrane lipopolysaccharide (LPS) degradation followed by inner membrane disruption, whereas Gram-positive bacteria exhibit simpler kinetics due to direct oxidative attacks on their thick peptidoglycan layer. Escherichia coli has long been used as the gold standard in photocatalytic sterilization studies owing to its aerobic nature and suitability for the colony-counting method. In contrast, Lactobacillus casei, a facultative anaerobe, can be cultured statically and evaluated rapidly using turbidity-based optical density measurements. Therefore, both organisms serve complementary roles depending on the experimental objectives—E. coli for precise quantification and L. casei for rapid, practical assessments of Gram-positive bacterial inactivation under laboratory conditions. We also describe sterilization using light alone while comparing it to photocatalytic sterilization and then discuss two innovative suspension-based photocatalyst systems: polystyrene bead-supported TiO₂/SiO₂ composites offering balanced reactivity and separability and magnetic TiO₂-SiO₂/Fe₃O₄ nanoparticles enabling rapid magnetic recovery. Future research directions should prioritize enhancing visible-light efficiency using metal-doped TiO₂ such as Cu-doped systems; improving catalyst durability; developing new applications of photocatalysts, such as protecting RO membranes; and validating scalability across diverse industrial and medical water treatment applications. Full article

Fouling is a major challenge in membrane-based filtration processes, leading to higher operating and capital costs. Developing new membranes with better fouling resistance has always been a research focus in the membrane field. In particular, designing functional surfaces which mitigate fouling is an effective approach. We successfully fabricated membranes with a graphene functional layer using a single-step laser irradiation known as laser-induced graphene (LIG) on the membrane surface. The LIG ultrafiltration (UF) membranes were prepared by directly lasing poly(ether sulfone) (PES) membrane substrates. Scanning electron microscopy demonstrated the successful ablation of the PES membranes with controlled thickness. Water filtration tests confirmed that the permeance increased by 240% as the laser power increased from 2.4 to 3.2 W; the membrane lased with the highest ablation power (LIG-P8) displayed a high water permeance of ~400 L m⁻² h⁻¹ bar⁻¹ and a corresponding bovine serum albumin (BSA) rejection of 92.5%. Fouling experiments using BSA, humic acid (HA), and sodium alginate showed better permeance recovery ratios (78–90%) with LIG membranes compared to the neat PES membrane (65–68%). LIG membranes were also evaluated for antibioufouling filtration tests, which showed exceptional biofilm resistance and potent antibacterial killing effects when treated with Staphylococcus aureus. Applied external voltage and contact time were the key variables to optimize the antibiofouling properties of the LIG UF membranes. Full article

In the context of guided bone regeneration (GBR), the selection of an appropriate resorbable membrane plays a crucial role in the clinical success of the procedure. Precise knowledge about the distinct differences in properties is fundamental for correct selection of the membrane. This article presents an integrated comparative analysis between membranes, conducted for this given purpose and one step beyond: to fabricate a novel membrane with dedicated enhanced properties according to the targeted function. Our previous analysis showed that polymer membranes that met most histopathological criteria also produced the most remarkable results when radiologically observed. The most effective scaffolds were those containing active macromolecules released conditionally and staged. The PLGA and polycaprolactone scaffolds were found in this category and they granted a marked increase in bone density and improvement in osteoinduction. Based on these results, we decided to create a new polycaprolactone membrane in order to compare it with a standard currently on the market, the Jason membrane. The Jason^® membrane is a natural collagen scaffold derived from porcine pericardium. Due to the unique production process, the membrane shows a natural honeycomb-like, multilayered collagen structure with an increased content of collagen type III, leading to remarkable tear resistance and a slow degradation rate. Also, the low thickness of 0.05–0.35 mm facilitates the soft tissue management. The Jason scaffold was compared to an innovative synthetic membrane based on polycaprolactone (PCL), focusing on their physicochemical characteristics, biological behavior, and clinical applicability. The Jason^® membrane was distinguished by its high biocompatibility and rapid integration, while PCL offered superior mechanical stability and long-term durability, making it a preferred option for complex or customized 3D regenerations. Based on this integrated analysis, we fabricated an innovative electrospun PCL membrane, enriched with a novel synthesized nanohydroxyapatite, in order to enhance its specific properties for the beneficial use in targeted reconstructions. Full article

Gas-assisted coaxial electrospinning (GACES), a simple and versatile technique for the large-scale fabrication of coaxial nanofiber membranes, possesses significant industrial potential across advanced manufacturing sectors including semiconductors—particularly for fabricating high-precision dielectric layers, high-uniformity encapsulation materials, and flexible semiconductor substrates requiring tailored core-shell architectures. However, there is still a lack of relevant studies on the effective regulation of the core-shell structures of coaxial fibers based on GACES, which greatly limits the batch preparation and wide application of coaxial fibers. Finite element simulation analysis of the flow field and development of the coaxial jet mechanics model with a gas-driven flow field—two key methodologies in this study—successfully uncovered the influence mechanism of gas-assisted flow fields on the core-shell structures of coaxial nanofibers. By adjusting the gas-assisted flow fields parameters, we reduced the total diameter of coaxial fibers by 47.33% (average fiber diameter: 334.12 ± 16.29 nm → 175.98 ± 1.18 nm), decreased the shell thickness by 72.98%, increased the core-shell ratio by 289% (core-shell ratio: 0.49 → 1.91), and improved the uniformity of the total diameter distribution of coaxial fibers by 30.64%. This study delivers a practical conceptual framework and robust experimental underpinnings for the scalable fabrication of coaxial nanofiber membranes with controllable core-shell structures, thereby promoting their practical application in semiconductor devices such as ultra-thin dielectric layers, precisely structured encapsulation materials, and high-uniformity templates for nanoscale circuit patterning. Full article