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Development of carbon monoxide-tolerant fluorescent reporter system functional under anoxic conditions in Eubacterium callanderi KIST612
No full textThis study aimed to develop a fluorescent reporter system optimized for acetogen Eubacterium callanderi KIST612, addressing key challenges such as autofluorescence and CO exposure. To support reporter selection, autofluorescence in E. callanderi KIST612 was characterized. Fluorescence-activating and absorption-shifting tags (FAST), particularly FAST1-HMBR, was identified as the most suitable candidate due to its spectral properties, kinetics, and compatibility with the anaerobic strain. Under strict anoxic environments, FAST1-expressing strains exhibited significantly greater fluorescence intensity than controls-4.55-fold in glucose and 4.54-fold in CO conditions. Functional validation using a CO-sensing system showed a proportional increase in fluorescence intensity with the increasing CO partial pressure (R2, 0.97), confirming the system's sensitivity and capability in anaerobic CO conditions.FALSEsciescopu
Polyethyleneimine-modified SnO2 electron transport layers enabling defect passivation and interface engineering for scalable and flexible perovskite solar cells
No full textDefect passivation and interfacial optimization in the tin oxide (SnO2) electron transport layer (ETL) remain critical challenges in advancing high-efficiency and scalable perovskite solar cells (PSCs). In this work, we report a novel interfacial engineering strategy using polyethyleneimine (PEI) as a multifunctional modifier for SnO2 ETLs. The amine groups in PEI chemically interact with surface hydroxyls, effectively suppressing oxygen vacancies and simultaneously increasing surface energy. This dual effect not only improves interfacial wettability and perovskite crystallization, but also significantly reduces interfacial recombination at the ETL/perovskite absorber. Consequently, PSCs fabricated on PEI-modified SnO2 achieved power conversion efficiencies of 22.58 % (rigid, 1 cm2) and 22.56 (flexible, 0.12 cm2), demonstrating both exceptional performance and compatibility with scalable processing. Our findings establish a simple yet powerful interface modification technique that offers mechanistic insight and practical advancement for the development of next-generation, scalable and flexible perovskite-based photovoltaics. © 2025 Elsevier B.V., All rights reserved.FALSEsciescopu
A Physics-Informed Reinforcement Learning Approach to Vehicle-to-Grid Control With Real-Time Battery Degradation
No full textThe Vehicle-to-Grid (V2G) system has been a significant solution for enhancing the power grid's stability and supporting renewable energy. However, the primary barrier to the practical application of V2G technology has been a fundamental economic conflict: the accelerated battery degradation from aggressive battery cycling required to provide grid services creates a direct trade-off between generating revenue from grid services and preserving the battery asset's life. Therefore, the objective of this research is to develop an intelligent control framework to optimize both the profit generated from grid services provided and the longevity of the batteries. The proposed Physics-Informed Deep Reinforcement Learning (PI-DRL) framework utilizes a Digital Twin of the electrochemical behavior of the batteries to generate a real-time physics-based cost signal of degradation, which guides the learning of the policy by a deep reinforcement learning agent. Comprehensive VPP simulation results demonstrate that the proposed PI-DRL framework outperforms all benchmark approaches, achieving significant increases in net profitability and drastic reductions in fleet-wide capacity fade. The agent learned sophisticated control strategies, including making proactive deviations from the optimal control trajectory to avoid acute mechanical stress on the battery and optimizing operations across a heterogeneous fleet by using robust chemistries for high-intensity grid service tasks. A key implication of this research is that there is now a viable blueprint for the economically sustainable and equitable provision of V2G services, with an asset-preserving strategy being the most profitable method.TRUEsciescopu
Data-driven demand response aggregation for public EV charging stations: Overcoming decoupled governance challenges
No full textElectrification of the transportation sector will expand the public charging infrastructure globally to 600 GW by 2030, enabling stations to mitigate renewable energy curtailment through an upward demand response. With prohibitive smart charging and bidirectional power flow costs, greedy charging-based demand response participation remains the only viable pathway for integrating electric vehicles (EVs) as flexible resources until advanced technologies mature. However, this integration is hindered by decoupled governance challenges unique to public charging stations. Our proposed data-driven aggregation framework addresses these challenges through machine learning techniques, providing practical solutions for demand response aggregators (DRAs) to effectively integrate distributed resources despite their inherent operational uncertainties. The framework utilizes readily available station-level data to support critical decision-making problems in market participation through three interconnected processes: comprehensive flexibility assessment, dispatchable demand response amount prediction for resources without market records, and efficient classification of distributed small-scale charging stations. Validation using data from 700 public charging stations on Jeju Island, South Korea, demonstrated the framework's effectiveness, revealing unique characteristics of EV charging stations compared to conventional demand resources. Economic analysis confirmed that our tier-based selective aggregation significantly improved cost-effectiveness over that of conventional practices in the actual market. This promotes reduction in the gap between DRAs’ cleared volume and actual dispatch amount, thereby contributing to cost-effective system operation. © 2025 Elsevier B.V., All rights reserved.FALSEsciescopu
Phosphate-Binding Zn(II)-Coordinated Antimicrobial Peptoids: Enhancing Selectivity through Specific Recognition of Bacterial Membranes
No full textThe global spread of multidrug-resistant bacteria underscores the urgent need for antimicrobial agents with enhanced efficacy and selectivity. Here, we developed antimicrobial peptoids conjugated with zinc-dipicolylamine (ZnDPA) and bivalent Zn2BPMP motifs for improved bacterial membrane recognition via phosphate binding. The Zn2BPMP-containing peptoids, 5_Zn-2 and 8_Zn-4, exhibited the highest bacterial selectivity, achieving an increase in selectivity index of >10-fold. Cytotoxicity assays confirmed reduced toxicity against mammalian cells. Mechanistically, Zn2BPMP conjugation enhanced binding to anionic bacterial surface components, including lipopolysaccharides and lipoteichoic acids, and promoted inner membrane disruption. Furthermore, in a model of multidrug-resistant E. coli-induced sepsis, 5_Zn-2 exhibited potent antimicrobial and anti-inflammatory activity with low in vivo toxicity and therapeutic efficacy. These findings provide insights into the rational design of antimicrobial peptoids and peptidomimetics to selectively target bacteria and highlight their potential as next-generation therapeutics.FALSEsciescopu
Impact of rare JAK/STAT germline mutations on vaccination-induced innate immune responses in a Tyrolian population
No full textVaccination triggers the release of pro-inflammatory cytokines, the stimulation of the Janus Kinase (JAK) – Signal Transducer and Activator of Transcription (STAT) pathway and the activation of interferon response genes. While some JAK/STAT variants are associated with hematopoietic malignancies, the impact of the vast majority is unknown. Here we identify JAK/STAT germline variants in a Tyrolian cohort, including octogenarians, and link specific rare variants to enhanced vaccine-induced interferon transcriptomic responses. AlphaFold 3 predicted conformational changes in JAK and STATs variants, impacting their interactions and formation of receptor complexes. We also identified co-occurring variants in TYK2 and other modulators of interferon signaling that possibly modify the impact of JAK and STAT variants in the innate immune response. Our results demonstrate that the vaccine-induced innate immune transcriptomic response can be used for an in vivo functional assessment of mutations controlling key genetic pathways in the innate immune response. © The author(s).FALSEscopu
Correlation functions in expanding universes
No full textBy using the braneworld model, we investigate the time evolution of microscopic and macroscopic correlations in expanding universes. To describe the FLRW cosmologies in the holographic setup, we take into account a braneworld moving in the p-brane gas geometry, where the radial motion of the braneworld determines the cosmology in the braneworld. We show that the braneworld model reproduces the standard cosmology exactly. In this braneworld model, we investigate the time-dependent mutual information between two disjoint macroscopic subregions and the time-dependent two-point functions in the expanding universes. We find that the mutual information becomes zero when the distance between two subregions is slightly larger than the subsystem size. We also find that it decreases as time and the density of matter increase. However, the microscopic two-point function in the short-distance limit decreases by a power law, whereas it is exponentially suppressed in the long-distance limit due to the screening effect. In addition, we find that the two-point function is also suppressed by a power law with time.FALSEsciescopu
Solid-phase crystallization of amorphous Ga2O3/sapphire(0001) thin films monitored using in-situ multimodal X-ray probe technique
No full textWe investigated the crystallization behavior and structural evolution of amorphous Ga2O3 thin films deposited on sapphire (0001) substrates via solid phase epitaxy (SPE) using a synchrotron-based in-situ multimodal X-ray probe station. Real-time X-ray diffraction (XRD) and electrical conductance measurements during post-annealing revealed that crystallization into the alpha-Ga2O3 phase begins at approximately 500 degrees C, accompanied by a marked increase in conductance owing to thermally activated carrier transport. High-resolution XRD confirmed the formation of a high-quality alpha-Ga2O3 film with the c-axis oriented along the surface normal and fully relaxed lattice parameters in the in-plane and out-of-plane directions. Azimuthal angle scans revealed six-fold symmetry, confirming epitaxial in-plane alignment between the alpha-Ga2O3 film and sapphire (0001) substrate. Rocking curve analysis yielded dislocation densities of similar to 1.07 x 10(8) (screw) and similar to 4.34 x 10(9) cm(-2) (edge), corresponding to a total threading dislocation density of approximately 4.45 x 10(9) cm(-2), which is comparable to previously reported values for directly grown alpha-Ga2O3 films. These findings demonstrate that SPE is a promising alternative to conventional epitaxy for producing high-quality alpha-Ga2O3 thin films. This approach enables phase-selective crystallization with excellent structural quality, without the need for high-temperature deposition or complex substrate engineering, thereby offering a viable pathway for integration into thermally sensitive device platforms.FALSEsciescopu