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Sustainable acid dye removal: A biocatalytic approach using glyoxal-immobilized oxidase enzymes
No full textImmobilized oxidase enzymes have been widely investigated for their potential to degrade dyes, and offer a promising approach for textile wastewater treatment. However, in many immobilization methods, a major obstacle in applying immobilized enzymes to wastewater treatment is the reliance on potentially toxic chemicals, in particular, crosslinking agents for covalent immobilization, which can introduce secondary risks to the aquatic ecosystem. This study evaluates the use of glyoxal, a less toxic alternative, as a crosslinking agent for immobilizing horseradish peroxidase (HRP) and laccase onto chitosan beads. The immobilized enzymes were tested for the removal of Acid Green 25 (AG 25) and Acid Red 1 (AR 1) dyes under various pH levels, temperatures, and contact times. At 30 °C and pH 6.5, the immobilized enzymes removed (80 −84) % of Acid Green 25 dye and 71 % of Acid Red 1 dye after 4 h. Characterization of the immobilized enzymes confirmed successful crosslinking and structural stability, while metabolite analysis suggested potential dye degradation pathways. By utilizing glyoxal at a lower concentration (0.4 %) compared to traditional glutaraldehyde methods (typically 0.8 %), this approach reduces chemical input and ecotoxicity while maintaining high dye removal efficiency. These findings highlight the potential of glyoxal-crosslinked immobilized enzymes on chitosan beads as a sustainable and effective solution for textile wastewater treatment. © 2025 Elsevier LtdFALSEsciescopu
Single-Step Synthesis of Mesoporous Vinyl Polymers via Hierarchical Assembly of Stereocontrolled Chains and Their Unique Properties
No full textMesoporous materials, vital in energy, environmental, and medical applications, require resource-intensive production. Mesoporous vinyl polymers, p-alkyl-N-phenyl-acrylamide (APAA) polymers is introduced, which offer unprecedented advantages in mass production. APAA monomers swiftly form syndiotactic chains through Monomer Aggregation-mediated Rapid, Radical Stereocontrolled (MARRS) polymerization, spontaneously creating mesoporous structures. Structural analyses (X-ray, NMR, DSC, FTIR, TEM, and Brunauer-Emmett-Teller measurements) and molecular mechanics simulations suggest the formation of Y-shaped clusters via intermolecular hydrogen bonding between the syndiotactic chains, which then form either a lamellar or hexagonal cylindrical structure containing mesopores. APAA polymers are highly processable, enabling the straightforward production of microfibers, films, and microparticles. They exhibit significant blue light emission (Quantum Yield: 7–18%) while maintaining exceptional transparency in the visible range. UV-crosslinked APAA polymer fibers, which have both superhydrophobicity and strong water adhesion (petal effect), along with crosslinked APAA polymer microparticles, are highly effective at absorbing liquid-phase volatile organic compounds (VOCs) such as chloroform, tetrahydrofuran, benzene, and toluene. They achieve both rapid absorption (<10 s) and high absorption capacity. Their remarkably simple and economical synthesis, together with their unique physicochemical properties, position APAA polymers as promising, commercially sustainable mesoporous materials with diverse applications such as UV absorbers, transparent blue-emitting films, anti-counterfeiting materials, and water remediation. © 2025 The Author(s). Small published by Wiley-VCH GmbH.TRUEsciescopu
Compact multimode interference coupler based on hybrid silicon rich nitride-thin film lithium niobate platform
No full textOn-chip multimode couplers are essential optical components in photonic integrated circuits (PIC). Recently, optical waveguides and devices based on lithium niobate on insulator (LNOI), also known as thin-film lithium niobate (TFLN), have gained significant attention due to their high refractive index contrast between the core and the cladding, enabling strong optical confinement [1]. However, CMOS compatible hybrid platform such as silicon rich nitride-thin film lithium niobate (SRN-LN) address existing challenges faced by monolithic TFLN platforms. These includes slanted waveguide sidewall, LiF diffusion, and LN redeposition during dry etching processes, which stem from the strong physical and chemical stability of LN material [2]. In this paper, we present the design and demonstration of a compact 1×2 MMI compact multimode interference (MMI) coupler coupler based on the hybrid SRN-LN platform. Furthermore, we analyze the MMI's performance in terms of loss, and uniform power splitting ratio. © 2025 Elsevier B.V., All rights reserved
Single-Molecule Investigation of Plasmonic Near-Field Effects on a Dissociation Reaction
No full textPlasmonic near-field effects have attracted more attention as a means of enhancing photoexcitation and photoresponses in materials and devices. Although chemical reactions are one of the important applications, a detailed microscopic understanding of the plasmonic near-field effect in chemical reactions is still lacking. In this study, we reveal that the degree of coupling between the plasmonic electric field and the molecular transition dipole moment governs the reactivity at the single-molecule level. This was demonstrated via single-molecule analysis of the reactivity for dimethyl disulfide weakly chemisorbed on Ag(111) by the combination of experiments using a scanning tunneling microscope (STM) and theoretical calculations. Through precise analysis of the dependence of the reactivity on the angle between the molecular axis and the local plasmonic field, the adsorption configuration dependence of dissociation can be explained by the interaction of the molecules with the plasmonic electric field anisotropically distributed at the nanogap in the STM junction. © 2025 American Chemical Society.FALSEsciescopu
Advanced strategies for enzyme–electrode interfacing in bioelectrocatalytic systems
Full text linkAdvances in protein engineering-enabled enzyme immobilization technologies have significantly improved enzyme–electrode wiring in enzymatic electrochemical systems, which harness natural biological machinery to either generate electricity or synthesize biochemicals. In this review, we provide guidelines for designing enzyme–electrodes, focusing on how performance variables change depending on electron transfer (ET) mechanisms. Recent advancements in enzyme immobilization technologies are summarized, highlighting their contributions to extending enzyme–electrode sustainability (up to months), enhancing biosensor sensitivity, improving biofuel cell performance, and setting a new benchmark for turnover frequency in bioelectrocatalysis. We also highlight state-of-the-art protein-engineering approaches that enhance enzyme–electrode interfacing through three key principles: protein–protein, protein–ligand, and protein–inorganic interactions. Finally, we discuss prospective avenues in strategic protein design for real-world applications. © 2024 The Author(s)TRUEsciescopu
Immuno-Oncological Study of PFKL Targeting and Discovery of an Anti-Aging Microbiome
No full textCancer immunotherapy and anti-aging therapies are among the hottest areas of research in modern medicine. This study explores both fields by identifying novel targets for cancer immunotherapy and discovering novel microbiome strains that exhibit anti-aging effects. First, we investigated the potential of phosphofructokinase (PFKL, liver type) as a novel therapeutic target for cancer immunotherapy from an immunological perspective. Analyzing clinical data, we found that patients with lower PFKL expression had a higher survival rate. Using CRISPR-Cas9-based gene editing technology, we created PFKL knockdown (KD) cells and performed a series of in vitro and animal model experiments. The results showed that the PFKL KD cell line induced antitumor effects through increased activation of T cells and other myeloid cells. These results suggest that PFKL may be a promising therapeutic target to improve the efficacy of cancer immunotherapy. Second, we demonstrated that gut microbial strains Lactococcus lactis LL23, GEN3013, and Bifidobacterium adescentis KCTC3216 can induce anti-aging effects. We first screened strains expressing key enzymes involved in the anti-aging pathway through cell experiments, and then used the selected strains in both cell and animal experiments to demonstrate their anti-aging efficacy. Furthermore, FACS analysis confirmed the anti-aging effects from an immunological perspective. These results highlight the therapeutic potential of these strains as new targets for anti-aging treatment. This study presents the possibility of overcoming the limitations of cancer immunotherapy and anti- aging treatments through two innovative approaches: PFKL KD and the discovery of new anti-aging strains. The findings provide a foundation for developing new therapeutic strategies in both fields and emphasize the practical applications of immunological and microbiological research.MasterAbstract i
Contents ii
I. Part 1. PFKL as a Novel Therapeutic Target Enhancing Cancer Immunotherapy via Immune
Activation 1
1. Introduction 1
2. Materials and Methods 3
3. Results and Discussion 11
4. Discussion 32
II. Part 2. Identification of Novel Microbiome Strains with Anti-Aging Potential and Immune-Modulating
Effects 34
1. Introduction 34
2. Materials and Methods 36
3. Results. 41
4. Discussion 55
V. References 57
VI. Acknowledgements 6
Thrombospondin-1 Modulation by Bifidobacterium spp. Mitigates Lung Damage in an Acute Lung Injury Mouse Model
No full textOur study shows that Bifidobacterium spp. supplementation reduces lung damage in acute lung injury by enhancing immune cell activity and restoring thrombospondin-1 levels, offering a promising therapeutic approach for the treatment of ALI/ARDS. Background: Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are critical conditions characterized by severe lung inflammation and damage, often exacerbated by mechanical ventilation. Probiotics, particularly those containing Bifidobacterium spp. (Bifidus) have shown promise in modulating immune responses and reducing inflammation. Methods: In this study, we investigated the effects of Bifidus supplementation in a mouse model of lipopolysaccharide induced ALI and ventilator-induced lung injury. Results: Our results demonstrate that Bifidus significantly ameliorates lung injury by enhancing efferocytosis and reducing pro-inflammatory cytokine levels. Single-cell RNA sequencing revealed significant changes in lung immune cell populations, particularly macrophages and monocytes, which showed increased efferocytosis activity and modulation of key signaling pathways such as TNF, MAPK and TLR. Notably, Bifidus feeding restored thrombospondin-1 levels in lung tissue, facilitating clearance of apoptotic cells and promoting resolution of inflammation. Conclusions: Overall, our study highlights the potential of Bifidus as a therapeutic strategy to mitigate lung injury in ALI/ARDS. © 2025 The AuthorsFALSEsciescopu
A study on the next-generation secondary batteries incorporating vanadium oxide-based cathodes
No full textMetal battery systems have emerged as promising candidates for next-generation energy storage due to their high capacity and low cost. Among them, high-power and energy lithium metal batteries (LMBs) and high- energy and safe aqueous zinc metal batteries (AZMBs) are considered two of the most promising and complementary systems for modern applications, including electric vehicles (EVs), advanced air mobility (AAM), and grid-scale energy storage systems (ESSs). However, the practical deployment of these systems remains hindered by electrode structural degradation and interfacial instability. To address these challenges, this dissertation presents system-level design strategies with in-depth degradation mechanism studies for both LMBs and AZMBs, focused on the use of vanadium oxide (VO) cathodes. VO is particularly attractive due to its high theoretical capacity, structural versatility, and cost-effectiveness, making it a strong candidate for achieving high-performance metal battery systems. For the LMB system, configuration of a low-voltage, high-capacity structural modified VO cathode with a low-concentration ether-based electrolyte (1 M LiFSI in DME, denoted E-LCE) is suggested. The nanoplate- stacked VO structure facilitates short Li+ diffusion pathways, while the E-LCE enables the formation of a thin, ionically conductive sulfur-rich cathode–electrolyte interphase (CEI) and a robust, elastic solid electrolyte interphase (SEI) on the lithium metal anode. This synergistic design delivers stable cycling at high current densities (5 C, full cell) and induces a favorable phase transition from α– to γ′– V2O5, enhancing both power and energy densities, along with long-term stability. Simultaneously, degradation mechanisms in VO-based AZMBs are elucidated, with particular focus on vanadium ion cross-talk as a critical but underexplored degradation pathway. Using a V2O5·nH2O cathode and 2 M ZnSO4 electrolyte, a vanadium shuttling is identified, in which dissolved vanadium species undergo spontaneous reduction at the zinc anode, leading to interfacial instability, open-circuit voltage (OCV) drift, and capacity fading, especially under moderate current densities (<500 mA g−1). From these findings, holistic strategies to suppress shuttling are also proposed. This dissertation highlights the importance of physicochemical insights into both material structures and interfacial reactions for the rational design of high performance next-generation metal battery systems.DoctorAbstract i
Contents ii
List of Figures iv
List of Tables x
Chapter 1. Introduction 1
Chapter 2. Design Strategy for High-Performance Lithium Metal Batteries: From Materials to Interfaces 10
2.1. Introduction 10
2.2. Research Background 15
2.2.1. Challenges and Opportunities in Lithium Metal Anodes 15
2.2.2. Critical Role of Electrode−Electrolyte Interfaces 16
2.2.3. Cathode Materials for Lithium Metal Batteries 19
2.2.4 Phase Transition of V2O5 and the Corresponding Operating Potential Range 22
2.3. Structural Modification of Vanadium Oxide Cathode 24
2.3.1. Motivation and Objectives 24
2.3.2. Experiments 26
2.3.3. Results and Discussion 28
2.3.3.1. Design of a high-performance vanadium oxide cathode through nanoarchitecture 28
2.3.3.2. Material Characterization of nanoplate-stacked vanadium oxide cathode 34
2.3.3.3. Electrochemical analysis of nanoplate–stacked vanadium oxide cathode 41
2.3.3.4. Cell performance of a LMB full-cell 45
2.3.4. Conclusion 48
2.4. Interfacial Engineering for High-Energy, High-Power, and Long-Life Lithium Metal Batteries 49
2.4.1. Motivation and Objectives 49
2.4.2. Experiments 51
2.4.3. Results and Discussion 54
2.4.3.1. Structural characterization of pristine VO and its electrochemical behavior 54
2.4.3.2. The interfacial evolution of the VO cathodes 76
2.4.3.3. The structural evolution of the VO cathodes 84
2.4.3.4. The electrochemical performances and stabilities of lithium metal anodes 90
2.4.3.5. High-energy and high-power performance of LMB full-cells 100
2.4.4. Conclusion 104
Chapter 3. A Mechanistic Study of Cross-Talk Toward Understanding Performance Degradation in Vanadium-Based Aqueous Zinc Metal Batteries 113
3.1. Introduction 113
3.2. Research Background 118
3.2.1. Vanadium Oxide Cathodes for Aqueous Zinc Metal Batteries 118
3.2.2. Undesirable Issues in VO-based AZMBs 122
3.2.3. Cathode-to-Anode Crosstalk 125
3.3. Experiments 128
3.4. Results and Discussion 130
3.4.1. Electrode characterization and electrochemical indications of interfacial cross-talk 130
3.4.2. Cathode reversibility and its limitation in explaining cross-talk 138
3.4.3. Current-density-dependent interfacial redox interactions between vanadium species and Zn anode 143
3.4.4. Voltage-driven onset of vanadium dissolution initiating cathode‒anode cross-talk 155
3.4.5. Redox-driven vanadium shuttling and self-discharge behavior in AZMBs 158
3.4.6. Mechanistic summary of vanadium-induced hidden cross-talk in VO-based AZIBs 165
3.5. Conclusion 167
Chapter 4. Conclusion 173
Acknowledgements 17
