Search Results (125)

Particulate matter (PM) pollution has become a major public health concern. Particularly, PM_0.3 in the air can cause significant damage to the human respiratory system. However, traditional air filtration materials, due to their limited protective functions, are facing challenges such as poor environmental adaptability, low transparency, and difficulties in balancing filtration efficiency with pressure drop. Inspired by the honeycomb structures and transparent dragonfly wings, this study successfully fabricated a bioinspired honeycomb-structured nanofibrous membranes (NFMs) using template-assisted electrospinning. By optimizing the mesh size of receiver, a directional distribution of the electric field was established on the receiver, promoting the simultaneous concentrated ordered stacking and sparse random orientation of fine-diameter nanofibers. This synergistic strategy of structural optimization and electric field modulation enables NFMs to achieve an optimal balance between filtration efficiency, pressure drop, environmental adaptability and transparency. Utilizing filtration mechanisms involving Brownian diffusion, electrostatic adsorption and physical interception, the honeycomb-structured NFMs achieved a filtration efficiency of over 98.51% for PM_0.3, with a pressure drop of only 34 Pa, whilst maintaining high transparency (85%) and high air permeability (130.8 mm/s). This bioinspired honeycomb-structured NFMs demonstrates broad application prospects in the field of air purification and offers novel insights for the development of multifunctional air filtration materials. Full article

Emerging micropollutants in drinking water sources represents a growing challenge for water treatment systems. Bisphenol-A (BPA) and 17β-estradiol (E2) are endocrine disruptors widely detected in aquatic matrices that are not efficiently removed by conventional treatment. This study evaluated, at the bench scale, operational performance and rejection of BPA and E2 by three nanofiltration membranes—NFM1, NFM2 and NFM3—operating at 8 bar and using ultrafiltered water from the Lago Norte Water Treatment Plant (WTP), Brasília/DF, Brazil, spiked with both compounds at 150–250 µg/L, as the feed matrix. Hydraulic parameters, such as permeate flux and water permeability, were assessed alongside rejection. NFM1 exhibited the highest permeate fluxes (136.1 and 171.7 L/h·m²); however, it showed the lowest rejection (E2: 57–73%; BPA: 28–60%). The NFM2 membrane showed intermediate rejection behavior (E2: 86–89%; BPA: 67–91%) but presented the lowest permeate flux (51.2 to 63.3 L/h·m²). The NFM3 membrane presented the highest rejection and greatest operational stability (E2: 90–95%; BPA: 95–97%), with a permeate flux of 59.1 to 67.0 L/h·m². Size exclusion was the predominant removal mechanism, though adsorption also contributed during the initial hours of operation. The results confirm a trade-off between permeate production and contaminant rejection, with no single membrane outperforming all others across all criteria. Full article

Ceramic nanofiber-based materials have wide applicability in high-temperature management and protection. The transformation of conventional two-dimensional ceramic nanofibrous membranes into three-dimensional nanofiber-based bulks can effectively improve their thermal insulation performance and expand their range of applications. Herein, lamellar-structured Al₂O₃-SiO₂ nanofibrous aerogels (LASO NFAs) with varying inorganic binder contents were prepared via a sequence of processes involving face-to-face stacking, impregnation, and calcination, using flexible Al₂O₃-SiO₂ nanofibrous membranes (ASO NFMs) as building units and aluminum dihydrogen phosphate as an inorganic binder. Varying the inorganic binder content in the aerogel matrix enables effective control over the compressive properties and interlayer spacing of the resulting aerogels. Specifically, the optimized LASO-20 NFAs demonstrated relatively good compression resilience, with a plastic deformation of 22.1% after undergoing 500 compressive cycles at a compressive strain of 50%. Moreover, profiting from the high-temperature resistance of ASO NFMs and substantial air content present within nanofiber interlayers, the LASO-20 NFAs with a thickness of 20 mm could effectively insulate against surface temperatures of 1000 °C down to 224 °C. Moreover, LASO-20 NFAs exhibited a room-temperature thermal conductivity of approximately 0.043 W·m⁻¹·K⁻¹, illustrating a favorable high-temperature thermal insulation characteristic. Furthermore, the LASO-20 NFAs presented promising service performance in extreme environments, providing a novel perspective in the development of new types of ceramic aerogels. Full article

Background: Human dental pulp stem cells (hDPSCs) are a promising source of multipotent mesenchymal stem cells (MSCs) for regenerative neurology because of their inherent neurogenic potential. However, robust and reproducible protocols for driving their terminal neuronal maturation in a fully defined, xeno-free environment are lacking. Methods: hDPSCs were isolated from a donor tooth and characterized for mesenchymal (CD105, CD90, CD73, CD13) and stemness-associated markers (SOX2, Oct3/4 and Nanog). Cells were differentiated in a novel, fully chemically defined medium 1% ITS medium (ITS: Insulin, Transferrin, Selenium) supplemented with glial cell line-derived neurotrophic factor (GDNF) or brain-derived neurotrophic factor (BDNF). Neuronal commitment and partial maturation were assessed via immunofluorescence, Western blot, and RT-PCR for markers such as NeuN (Neuronal nuclei) and NF-M (Neurofilament medium chain), and functionally by whole-cell patch-clamp electrophysiology. Results: Although undifferentiated hDPSCs expressed neural progenitor markers (βIII-tubulin and Nestin), only GDNF treatment in a chemically defined medium significantly upregulated mature neuronal markers (NeuN and NF-M) and downregulated mesenchymal markers. Importantly, GDNF-treated cells exhibited key functional changes, including hyperpolarized resting membrane potentials, increased membrane capacitance, and elevated input resistance, which are electrophysiological hallmarks of neural precursor or early neuronal maturation, compared to control cells cultured in medium containing fetal bovine serum (FBS). Although action potentials were not elicited, this represents a significant advancement toward achieving a functional neuronal state. Conclusion: This study demonstrates that a fully chemically defined medium enables GDNF to drive hDPSCs beyond the neural progenitor state towards a partially mature neuronal phenotype. This defined medium protocol eliminates serum variability, enhances reproducibility, and provides a critical step towards standardizing hDPSC-derived neuronal cells for disease modeling and cell-based therapy. Full article

Fermented soybean paste, a traditional high-salt condiment, faces challenges in standardization and quality control due to its reliance on natural fermentation. This study systematically evaluated the effects of a defined starter culture, Tetragenococcus halophilus CICC 10286, on soybean paste fermentation by comparing natural fermentation (NF) and fortified fermentation (FF). Compared with NF, FF maintained a higher moisture in the later stage (NF-LS: 50.30%; FF-LS: 60.08%) and lower total acid levels in the middle and later stages (NF-MS: 1.58 g/100 g; FF-MS: 0.96 g/100 g; NF-LS: 2.23 g/100 g; FF-LS: 1.11 g/100 g). Although protein degradation was more pronounced in the FF group at the midpoint (p < 0.0001), the lower accumulation of amino acid nitrogen suggests a potential shift in nitrogen metabolism, possibly toward enhanced transamination or deamination processes. Free amino acid profiling indicated that FF facilitated earlier accumulation of umami and sweet amino acids, but the total free amino acid content in the later stage was lower. Specifically, Glu and Asp reached 724.47 nmol/L and 305.52 nmol/L, respectively, in NF-LS, whereas the corresponding values in FF-LS were 397.16 nmol/L and 275.46 nmol/L. Meanwhile, Pro reached 337.81 nmol/L in FF-MS, indicating earlier accumulation of some amino acids under FF. Notably, the proportion of bitter amino acids in the FF group was reduced in the later stage. Microbial community analysis showed that FF promoted the enrichment of Tetragenococcus and halotolerant bacteria, such as Halomonas, at the midpoint, and increased the relative abundance of the aroma-producing yeast Zygosaccharomyces (NF-MS: 37.73%; FF-MS: 65.11%). Functional prediction based on PICRUSt2 suggested a higher predicted abundance of genes involved in pyruvate metabolism and branched-chain amino acid degradation in the FF group. These findings demonstrate that T. halophilus CICC 10286, as a starter culture, can effectively modulate the fermentation of soybean paste, providing a scientific basis for developing standardized and quality-controlled fermentation processes. Full article

Alzheimer’s disease (AD) is an age-related neurodegenerative disorder characterized by progressive synaptic dysfunction, axonal pathology, and cognitive decline, with the hippocampal circuits showing particular vulnerability during disease progression. However, early-life nutritional interventions may influence long-term synaptic resilience. In this study, we investigated the long-term effects of prenatal and lactational supplementation with choline, UMP, and fish oil in the 5XFAD mouse model. To this end, hippocampal synaptic and axonal pathology was assessed at 3, 6, and 9 months using Western blotting and immunofluorescence to measure synaptophysin, PSD-95, and neurofilament medium chain (NF-M), alongside a multidimensional behavioral battery that evaluated cognitive, affective, motor, and sensory outcomes. Results showed that early-life supplementation did not significantly improve the learning performance decline, increase nociception, or reverse changes in anxiety behavior in transgenic mice. However, it attenuated synaptic decline in transgenic animals by partially preserving synaptophysin and PSD-95 levels and reducing NF-M elevations. These molecular effects were accompanied by selective behavioral modulation, including preserved learning dynamics, altered anxiety-like behavior, and delayed nociceptive hypersensitivity, while late-stage motor impairments remained largely unaffected. Overall, prenatal and lactational supplementation produced modest, age-dependent effects on synaptic markers and partially prevented neurodegenerative progression in the 5XFAD model. Full article

Underwater sonar object detection is challenging because targets are often small, boundaries are blurred, background clutter is strong, and labeled sonar data are limited. To address these issues, we propose T2C-DETR, a detector built on RT-DETR with three task-oriented improvements: (i) a Transformer–Convolution dual-channel backbone (TCDCNet) for complementary global-context and local-detail modeling, (ii) a Noise Filtering Module (NFM) inserted before neck fusion to suppress noise-dominated activations, and (iii) a stage-wise transfer-learning strategy tailored to small sonar datasets. We evaluate the method under three pre-training sources (COCO 2017, DOTA, and an infrared dataset) and then fine-tune on a self-built sonar dataset. Experimental results show that T2C-DETR achieves AP50 of 97.8%, 98.2%, and 98.5% at 72–73 FPS, consistently outperforming the RT-DETR baseline, YOLOv5-Imp, and MLFFNet in the accuracy–speed trade-off. These results indicate that combining global–local representation learning with targeted noise suppression is effective for practical real-time sonar detection. Full article

This study examines the determinants of profitability for 21 Bulgarian commercial banks over the period from the first quarter of 2007 to the first quarter of 2025, using financial statement data. Bank profitability is measured by return on assets (ROA) and return on equity (ROE) and modeled within a panel autoregressive distributed lag (PMG-ARDL) framework. The empirical specification combines bank-specific and macroeconomic variables, allowing for the identification of both long-run equilibrium relationships and short-run bank-level dynamics. The long-term results indicate that the net interest margin (NIM), net fee and commission margin (NFM), government bond yields, the growth of the gross domestic product (GDP), and the loan-to-deposit ratio (LDR) positively affect profitability. On the other hand, higher unemployment, rising housing prices, increased loan loss impairments, and the ratio of cash holdings to total assets reduce profitability. The findings provide policy-relevant insights for bank management, regulators, and macroprudential authorities regarding efficiency, income diversification, and credit risk management. The findings facilitate a more comprehensive assessment of banking sector resilience and provide a foundation for the development and refinement of macroprudential and supervisory policy measures. Full article

Electromagnetic shielding (EMS) materials play an important role in modern technology and industry, especially in electronic equipment, communication technology, military applications and so on. With the continuous progress of technologies and the increasing demands for functional materials, EMS materials are expanding towards flexibility and being lightweight. Recently, metal–organic frameworks (MOFs) have garnered significant attention in the EMS field due to their unique structure and adjustable properties. In this paper, alloy-based porous nanospheres (CCZ-C) were fabricated by heat-treatment using CoCuZn-MOFs as precursors, and then electrospun CCZ-C/PVDF nanofiber membranes (NFMs) were prepared in a large-quantity by blending them with PVDF. Afterwards, a hierarchical porous structured NFM (MPPA) was obtained by loading a highly conductive Ag nanolayer on the surface of CCZ-C/PVDF nanofibers using pDA as a binder. By adjusting the CCZ-C content, it was determined that the EMS performance of MPPA was highest when the CCZ-C content was 2 wt.%, with an average SSE of 12,017.01 dB·cm²·g⁻¹. This was because the hierarchical porous structure formed by adding an appropriate amount of CCZ-C further improved the electromagnetic attenuation and impedance matching of MPPA. Full article

This review highlights the growing relevance of ion-exchange nanofibrous membranes (IEX-NFMs) in membrane chromatography (MC) for protein purification, emphasising their structural advantages such as high porosity, tunable surface functionality, and low-pressure drops. While the adsorption of IEX-NFMs in MC is expanding due to their potential for high throughput and rapid mass transfer, a critical limitation remains: the precise binding capacity of these membranes is not well understood. Traditional experimental methods to evaluate protein–membrane interactions and optimise binding capacities are labour-intensive, time-consuming, and costly. Therefore, this review underscores the importance of computational modelling as a viable predictive approach to guide membrane design and performance prediction. Yet major obstacles persist, including the challenge of accurate representation of the complex and often irregular pore structures, as well as limited and/or oversimplified adsorption models. Along with molecular-scale simulations such as molecular dynamics (MD) simulations and quantum simulations, meso-scale simulations can provide insight into protein–fibre and protein–protein interactions under varying physicochemical conditions for larger time scales and lower computational burden. These tools can help identify key parameters such as binding accessibility, ionic strength effects, and surface charge density, which are essential for the rational design and performance prediction of IEX-NFMs. Moreover, integrating simulations with experimental validation can accelerate optimisation process while reducing cost. This technical review sets the foundation for a computationally driven design framework for multifunctional IEX-NFMs, supporting their use in next-generation chromatographic separations and broadening their applications in bioprocessing and analytical biotechnology. Full article

Sodium-ion batteries (SIBs) present a sustainable alternative to lithium-ion systems due to the abundance and low environmental impact of sodium. However, their integration into multifunctional structural battery systems that combine electrochemical and mechanical properties remains unexplored. This work investigates the electrochemical performance of sodium-ion chemistry within a structural battery framework using unsized carbon fiber (UCF) as both a structural substrate and active electrode material. Ultrasonic spray coating was employed to deposit Mesocarbon Microbeads (MCMB) and NaNi_1/3Fe_1/3Mn_1/3O₂ (NFM) on UCF to form hybrid anode and cathode half-cells, respectively, with 1 M NaPF₆ in diglyme electrolyte. The MCMB on UCF hybrid anode demonstrated dual graphitic and carbon fiber storage mechanisms, achieving 50 mAh g⁻¹ capacity over 500 cycles at 1C with excellent Coulombic efficiency. The NFM–UCF cathode exhibited an initial capacity of 27.5 mAh g⁻¹ and maintained over 80% capacity retention for 230 cycles, continuing to cycle stably beyond 400 cycles. Post-cycling SEM imaging revealed surface cracking, particle expansion, and gas-pocket formation in both electrodes. These results demonstrate the electrochemical viability of sodium-ion chemistry in a multifunctional structural configuration and establish ultrasonic coating as a scalable, precise method for fabricating carbon fiber electrodes toward future sodium-ion structural batteries. Full article

O3-type NaNi_1/3Mn_1/3Fe_1/3O₂ (NFM) cathodes for sodium-ion batteries face critical challenges of sluggish Na⁺ diffusion and structural degradation during cycling. In this study, we implement an Sb³⁺ doping strategy that enhances structural stability and interfacial stability by modulating the NFM grain morphology to promote densification of primary particles and shorten Na⁺ migration paths. The optimized Sb-doped NFM1Sb (1%mol Sb) cathode exhibits excellent electrochemical performance, achieving 86.48% capacity retention after 200 cycles at 1 C and a high rate capability of 122.2 mAh g⁻¹ at 5 C. These improvements are attributed to the alleviation of stress concentration and suppression of microcrack formation during cycling. This work demonstrates the critical role of grain morphology regulation through heavy-metal doping in developing long-life and high-rate SIBs, providing a viable pathway toward next-generation energy storage systems. Full article

With their considerable capacity and structurally favorable characteristics, layered transition metal oxides have become strong contenders for cathode use in sodium-ion batteries (SIBs). Nevertheless, their practical deployment is challenged by pronounced capacity loss, predominantly induced by unstable cathode–electrolyte interphase (CEI) at elevated voltages. In this study, difluoroethylene carbonate (DFEC) is introduced as a functional electrolyte additive to engineer a robust and uniform CEI. The fluorine-enriched CEI effectively suppresses parasitic reactions, mitigates continuous electrolyte decomposition, and facilitates stable Na⁺ transport. Consequently, Na/NaNi_1/3Fe_1/3Mn_1/3O₂ (Na/NFM) cells with 2 wt.% DFEC retain 78.36% of their initial capacity after 200 cycles at 1 C and 4.2 V, demonstrating excellent long-term stability. Density functional theory (DFT) calculations confirm the higher oxidative stability of DFEC compared to conventional solvents, further supporting its interfacial protection role. This work offers valuable insights into electrolyte additive design for high-voltage SIBs and provides a practical route to significantly improve long-term electrochemical performance. Full article

The O3-type layered oxide materials have the advantage of high specific capacity, which makes them more competitive in the practical application of cathode materials for sodium-ion batteries (SIBs). However, the existing reported O3-type layered oxide materials still have a complex irreversible phase transition phenomenon, and the cycle life of batteries needs, with these materials, to be further improved to meet the requirements. Herein, we performed structural characterization and electrochemical performance tests on O3-NaNi_0.6−xFe_0.25Mn_0.15Mg_xO₂ (x = 0, 0.025, 0.05, and 0.075, denoted as NFM, NFM-2.5Mg, NFM-5.0Mg, and NFM-7.5Mg). The optimized NFM-2.5Mg has the largest sodium layer spacing, which can effectively enhance the transmission rate of sodium ions. Therefore, the reversible specific capacity can reach approximately 148.1 mAh g⁻¹ at 0.2C, and it can even achieve a capacity retention of 85.4% after 100 cycles at 1C, demonstrating excellent cycle stability. Moreover, at a low temperature of 0 °C, it also can keep capacity retention of 86.6% after 150 cycles at 1C. This study provides a view on the cycling performance improvement of sodium-ion layered oxide cathodes with a high theoretical specific capacity. Full article

Mainlobe suppression jamming significantly degrades radar detection performance. The conventional blind source separation (BSS) algorithms often fail under high-jamming-to-signal-ratio (JSR) and low-signal-to-noise-ratio (SNR) conditions. To overcome this limitation, we propose an enhanced BSS method combining variational mode decomposition (VMD) and wavelet packet decomposition (WPD), termed VMD-WPD-JADE. The proposed approach first applies VMD-WPD for noise reduction in radar signals and then utilizes the JADE algorithm to compute the separation matrix of the denoised signals, effectively achieving blind source separation of radar echoes for interference suppression. We evaluate the method using noise-amplitude modulation and noise-frequency modulation jamming scenarios. The experimental results show that at a JSR = 50 dB and an SNR = −5 dB, our method successfully separates the target signals. Compared with the conventional blind source separation (BSS) algorithms, the proposed technique demonstrates superior robustness, achieving a 4–11% improvement in the target detection probability under noise-amplitude modulation (NAM) jamming and a 4–16% enhancement under noise-frequency modulation (NFM) jamming within a signal-to-noise ratio (SNR) range of −5 dB to 5 dB. Full article