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Double Raschel-Structured Fabric Based on SnTiO3 Nanorod-Embedded 8-Petal Cross-Section PVDF Fibers for an Advanced Disaster Warning System

ACCEPTAdvanced Functional Materials

This study investigates both structural and non-structural effects on the piezoelectric performance of polyvinylidene fluoride (PVDF) fibers, focusing on the impact of double Raschel fabric components. It identifies key factors influencing performance, with emphasis on optimizing fiber cross-sectional shape, specifically an eight-petal structure. This structure enhances piezoelectric output with an open-circuit voltage (Voc) of 41.28 V and short-circuit current (Isc) of 6.140 µA due to its large surface area. Incorporating 5% SnTiO3 nanorods as high-relative permittivity fillers results in maximum performance improvement. Structural optimization using double Raschel fabric with different spacer yarn lengths reveals that the 5 mm configuration provides the best performance, achieving a Voc of 92.80 V and Isc of 4.130 mA. The double Raschel structure has the most significant impact on piezoelectric performance, followed by the full transition of the structure to PVDF embedded with 5% SnTiO₃ nanorods. Modifying the spacer yarn composition plays a crucial role in enhancing Isc. The effect of air volume is found to be more dominant than that of the spacer yarn length. Notably, the optimized double Raschel structure fabrics demonstrate high durability as real-time landslide warning systems, capable of generating piezoelectric output with body motions and sending real-time warning messages via Bluetooth under simulated landslide conditions.

Electronic Nose Based on a Multi-Thin Film Transistor Sensor Array Structure for Detecting Odorants with High Selectivity

ACCEPTAnalysis and Sensing

Electrical noses that mimic the human olfactory system have been developed to detect odors or flavors. Unfortunately, little research on sensing reactions to various odors like a human nose can be found in the literature. Herein, an electronic nose is proposed using a multi-thin film transistor (TFT) sensor array with various polymer selectors and multi-output signal processing to detect various odorants with high selectivity. Through the combination of multi-output produced by eight polymer variables based on indium gallium zinc oxide (IGZO) TFTs, a specific radar pattern and its selectivity are generated for the eight different odor substances. Eight multi-output signal processing reduced the correlation coefficient of similarity from 77.9% to 45% relative to the case of four multi-output processing. Because the polymers have different functional groups, polymers showed specific reactions to various odorants, like the human's system, and multi-output analysis could distinguish various odors, even if polymers did not show single selectivity to a specific odor. And the sensitivity improved when compared to two-terminal structures by using TFTs based on IGZO. The advantage is that it can classify multiple odors with good selectivity and sensitivity. This sensor and signal processing concept can be applied to E-nose systems capable of odor monitoring. © 2025 Wiley-VCH GmbH.

The kinase ATM delays Arabidopsis leaf senescence by stabilizing the phosphatase MKP2 in a phosphorylation-dependent manner

2025-04Plant Cell, v.37, no.4

Arabidopsis thaliana (Arabidopsis) Ataxia Telangiectasia Mutated (ATM) kinase plays a vital role in orchestrating leaf senescence; however, the precise mechanisms remain elusive. Here, our study demonstrates that ATM kinase activity is essential for mitigating age- and reactive oxygen species-induced senescence, as restoration of wild-type ATM reverses premature senescence in the atm mutant, while a kinase-dead ATM variant is ineffective. ATM physically interacts with and phosphorylates Mitogen-Activated Protein Kinase Phosphatase 2 (MKP2) to enhance stability under oxidative stress. Mutations in putative phosphorylation sites S15/154 on MKP2 disrupt its phosphorylation, stability, and senescence-delaying function. Moreover, mutation of mitogen-activated protein kinase 6, a downstream target of MKP2, alleviates the premature senescence phenotype of the atm mutant. Notably, the dual-specificity protein phosphatase 19 (HsDUSP19), a predicted human counter protein of MPK2, interacts with both ATM and HsATM and extends leaf longevity in Arabidopsis when overexpressed. These findings elucidate the molecular mechanisms underlying the role of ATM in leaf senescence and suggest that the ATM-MKP2 module is likely evolutionarily conserved in regulating the aging process across eukaryotes.

Optical Properties of Macrocyclic Chiral Molecules: The Limitations of Ring Size Increase

2025-04The Journal of Physical Chemistry Letters, v.16, no.15, pp.3715 - 3720

Chiral macrocyclic molecules are extensively investigated as potential candidates to develop organic emitters exhibiting circularly polarized luminescence (CPL) with large dissymmetry factors (g). Here, based on time-dependent density functional theory calculations, we investigate the relationship between macrocycle size and chiral properties. Our results underline that the rotatory strength (R) of the transition to the first excited state (S0 -> S1) increases linearly with the macrocycle loop area. While this evolution could promote high g values in the case of very large rings, it is found that the increase in system size can lead to energetic quasi-degeneracy of several low-lying transitions. In large macrocycles, among those transitions, it is the slightly higher-energy transitions possessing large oscillator strengths but small g values that come to dominate over the S0 -> S1 transition. Also, the corresponding decrease in energy spacing among these lowest excited states can trigger a broken symmetry of the S1-state geometry via a pseudo Jahn-Teller effect. Overall, our results highlight that in large macrocycles the CPL can gain in intensity but this occurs at the expense of the g value. Thus, it is critical that the interaction of the S0 -> S1 transition with higher-energy states be carefully considered when designing large-size CPL emitters.

Neural activation in a septal area is related to intrinsic motivation for non-courtship singing in adult zebra finches

2025-04Scientific Reports, v.15, no.1

Intrinsic motivation, which drives animals, including humans, to exhibit various voluntary behaviors, spontaneously originates within the brain without immediate external stimuli such as rewards or punishments. The zebra finch, a songbird, provides an ideal model for studying the neural substrates of intrinsic motivation because male birds spontaneously produce many renditions of non-courtship song ("undirected song") with a highly quantifiable structure for vocal practice. Here, we identified a brain area associated with intrinsic motivation for undirected singing through brain-wide mapping of neuronal activity using immediate early gene expression in birds with different levels of singing motivation. We found that birds with relatively high singing motivation exhibit increased expression levels of Arc mRNA in a septal area, the nucleus of the hippocampal commissure (NHpC), compared with birds with low singing motivation. Such high Arc mRNA expression was not observed after highly motivated birds decreased their singing motivation. These findings demonstrate that neuronal activity in the NHpC is associated with the degree of singing motivation, marking a crucial initial step in understanding the neural circuitry regulating intrinsic motivation for spontaneous singing behavior in songbirds.

Targeted NMDA receptor knockdown in recall-activated neuronal ensembles impairs remote fear extinction

2025-04Molecular Brain, v.18, no.1

Fear extinction training in rodents decreases fear responses, providing a model for the development of post-traumatic stress disorder therapeutics. Fear memory recall reactivates the consolidated fear memory trace across multiple brain regions, and several studies have suggested that these recall-activated neurons are re-engaged during extinction. However, the molecular mechanisms linking this reactivation to extinction remain largely elusive. Here, we investigated the role of N-Methyl-d-Aspartate receptors (NMDARs) in remote memory recall-activated neurons within the basolateral amygdala and the medial prefrontal cortex during extinction training in mice. We found that Grin1 knockdown in these specific ensembles impaired extinction of remote fear memory, but did not reduce their reactivation during retrieval of the extinguished memory. These data suggest that while reactivation of these neuronal populations persists, their NMDARs are crucial for driving the synaptic plasticity needed to extinguish remote fear memories.

Ce-doped NiCoP/ Co3O4 composite Nanostructures on Ni foam and their enhanced performance for water and urea electrolysis

2025-08Journal of Colloid and Interface Science, v.692

Producing hydrogen through freshwater or urea-containing wastewater electrolysis using renewable electricity requires multifunctional catalysts made from nonprecious metals. In the current study, we disclose the rational fabrication of oxide/phosphide heterostructure nanorods with rare earth metal doping on nickel foam (NF), denoted Ce-NiCoP/Co3O4/NF, via partial phosphorization. Benefiting from intrinsic interface formation and doping effects, the interaction between the coupling components facilitates electron transfer, optimizing the electronic configuration of the Ce-NiCoP/Co3O4/NF catalyst. Ce-NiCoP/Co3O4/NF exhibited a competitive potential of − 0.151 V for hydrogen evolution reaction, 1.50 V for oxygen evolution reaction (OER), and 1.33 V (versus reversible hydrogen electrode) toward urea oxidation reactions (UOR) at 100 mA cm−2. In situ Fourier-transform infrared combined with electrochemical analysis detects *OOH and *O2− intermediates in OER, as well as CO32− and CNO− ions, alongside the N–H vibration in UOR, providing deeper insight into the OER and UOR mechanisms on the Ce-NiCoP/Co3O4/NF. More importantly, the catalyst exhibited an activity of 20 mA cm−2 requiring voltages as low as 1.52 V for unassisted water splitting and 1.27 V for urea-assisted electrolysis. © 2025 Elsevier Inc.

Two-step polymerization for tailored donor-acceptor interactions driving efficient hydrogen evolution in visible-light photocatalysts

ACCEPTEES Catalysis

The development of materials for organic solar cells has made significant strides through the strategic combination of diverse donor structures with acceptor units in polymer backbones. In contrast, semiconducting polymers for photocatalytic hydrogen evolution have primarily focused on acceptor moieties, with limited exploration of donor contributions, primarily owing to the emphasis on designing active sites for proton reduction in inorganic catalysts. To investigate the impact of highly electron-donating moieties on photocatalytic performance, we designed and synthesized benzothiadiazole (BT)-based polymers with randomly incorporated benzodithiophene (BDT) and fluorene units via a streamlined one-pot Stille-Suzuki two-step polymerization. Comprehensive molecular characterization and optical spectroscopic analyses confirmed the successful synthesis of the target polymers. Photocatalytic hydrogen evolution studies, supported by photophysical and spectroscopic investigations, demonstrated that optimizing the proportion of BDT units in the polymer backbone enhances hydrogen evolution rates significantly. Additionally, comparative analyses further highlighted the distinct differences in the photocatalytic efficiency between the BDT and fluorene donor units, providing critical insights into their functional roles. This work underscores the potential of advancing polymer photocatalysts by fine-tuning donor-acceptor interactions through optimization of donor moiety composition, offering a robust framework for achieving superior photocatalytic performance. © 2025 RSC.

Emerging fiber-based neural interfaces with conductive composites

ACCEPTMaterials Horizons

Neural interfaces that enable bidirectional communication between neural systems and external devices are crucial for treating neurological disorders and advancing brain-machine interfaces. Key requirements for these neural interfaces are the ability to modulate electrophysiological activity without causing tissue damage in the nerve system and long-term usability. Recent advances in biomedical neural electrodes aim to reduce mechanical mismatch between devices and surrounding tissues/organs while maintaining their electrical conductivity. Among these, fiber electrodes stand out as essential candidates for future neural interfaces owing to their remarkable flexibility, controllable scalability, and facile integration with systems. Herein, we introduce fiber-based devices with conductive composites, along with their fabrication technologies, and integration strategies for future neural interfaces. Compared to conventional neural electrodes, fiber electrodes readily combine with conductive materials such as metal nanoparticles, carbon-based nanomaterials, and conductive polymers. Their fabrication technologies enable high electrical performance without sacrificing mechanical properties. In addition, the neural modulation techniques of fiber electrodes; electrical, optical, and chemical, and their applications in central and peripheral nervous systems are carefully discussed. Finally, current limitations and potential advancements in fiber-based neural interfaces are highlighted for future innovations.

Layered Iron Vanadate for High-Performance and Stable Cathode Material for Aqueous Manganese Batteries

ACCEPTAdvanced Science

Aqueous rechargeable metal batteries have gained significant attention because of the low cost, high capacity, and inherent safety offered by nonflammable water-based electrolytes. Among these, Mn-based systems are promising owing to their intrinsic stability, abundance, affordability, and high energy density. Despite these advantages, the development of suitable host structures for Mn storage remains underexplored. This study introduces layered iron vanadate, FeV3O91.1H(2)O, as a new cathode material for aqueous Mn batteries, demonstrating exceptional performance. The cathode exhibits a reversible capacity of 306.9 mAh g(-1) at 0.25 A g(-1) and an excellent rate performance of 210.6 mAh g(-1) at 2 A g(-1). In addition, FeV3O91.1H(2)O exhibits outstanding cycling stability, retaining 73.4% of its initial capacity after 3000 cycles at 3 A g(-)(1), which is attributed to its low layered volume expansion. The underlying reaction mechanism is elucidated through spectroscopic and microscopic analyses. When integrated into the final Mn cell, the cathode system demonstrates superior performance compared to Zn batteries, underscoring its potential for next-generation aqueous battery systems. These findings advance the aqueous Mn battery technology, paving the way for safer, more cost-effective, and high-performance energy storage solutions.

Engineered extracellular vesicles with surface FGF21 and enclosed miR-223 for treating metabolic dysfunction-associated steatohepatitis

2025-10Biomaterials, v.321

Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive liver disorder with a complex pathogenesis that requires combination therapies rather than monotherapies. Extracellular vesicles (EVs) exhibit inherently efficient delivery to the liver and can be engineered to carry various therapeutic substances, making them promising agents. In this study, EVs were engineered to display fibroblast growth factor 21 (FGF21) on their surface and encapsulate miR-223 (223/F-EVs), aiming to improve steatosis and alleviate inflammation and fibrosis, respectively. Introducing the 223/F-EVs into human liver cell lines significantly reduced both basal and induced levels of lipid storage, inflammation, and fibrosis markers. Furthermore, using an FGF21-blocking antibody or miR-223 inhibitor effectively diminished the efficacy of the 223/F-EVs, confirming the essential roles of FGF21 and miR-223 in these processes. In a Choline-Deficient, L-Amino acid-defined, High-Fat Diet (CDAHFD)-fed mouse model, intravenously administered 223/F-EVs demonstrated liver-preferential delivery and a marked reduction in the MASH phenotype without compromising bone density, unlike conventional FGF21 treatment. Collectively, 223/F-EVs convey FGF21 and miR-223 exclusively to the liver, offering strategic advantages by mitigating MASH progression via multiple pathways. This study lays a solid foundation for further investigation of engineered EVs as a transformative therapeutic approach for treating MASH. © 2025 Elsevier Ltd

Role of phospholipase Cη1 in lateral habenula astrocytes in depressive-like behavior in mice

ACCEPTExperimental & Molecular Medicine

Phospholipase C (PLC) enzymes play crucial roles in intracellular calcium-signaling transduction. Several brain PLC subtypes have been extensively studied, implicating them in psychiatric disorders such as depression, epilepsy and schizophrenia. However, the role of the recently identified PLCη remains largely unknown. We found that PLCη1 is prominently expressed in lateral habenula (LHb) astrocytes. Here, to investigate its physiological role, we generated astrocyte-specific PLCη1 conditional knockout (cKO) mice (Plch1f/f; Aldh1l1-CreERT2). In these cKO mice, we observed a reduction in cellular morphological complexity metrics, such as total process length, as well as a decrease in the passive membrane conductance of LHb astrocytes. Additionally, neuronal function was impacted by the cKO, as the synaptic efficacy and firing rates of LHb neurons increased, while extrasynaptic long-term depression was impaired. Both tonic α-amino-3-hydroxy-5-methyl-4-isoxazolepdlropionic acid receptor/N-methyl-d-aspartate receptor (AMPAR/NMDAR) currents and extracellular glutamate levels were reduced. Interestingly, chemogenetic activation of astrocytes restored the reduced tonic AMPAR/NMDAR currents in cKO mice. Furthermore, LHb astrocyte-specific deletion of PLCη1 via AAV-GFAP-Cre injection induced depressive-like behaviors in mice, which were reversed by chemogenetic activation of LHb astrocytes. Finally, we found that restraint stress exposure decreased Plch1 mRNA expression in the LHb. These findings suggest that PLCη1 could be a potential therapeutic target for depression and highlight the critical role of astrocytes in the etiology of neuropsychiatric disorders. © The Author(s) 2025.