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Ice Recrystallization Inhibition via 2D Janus Peptide Nanosheets
No full textAntifreeze proteins (AFPs) play a key role in the survival of polar organisms by selectively binding to specific ice crystal facets and regulating their growth. To mimic this mechanism, a series of amphiphilic peptides were developed incorporating aromatic residues, anionic groups, and hydrophobic tails. These peptides spontaneously self-assembled into two-dimensional Janus nanosheets. At the nanoscale peptide binds to ice crystal surfaces to block their growth, while at the macroscale hydrophobic face prevents water access to inhibit ice recrystallization. Cryo in-situ imaging revealed binding between the nanosheets and ice surfaces. These findings highlight the potential of amphiphilic peptide nanosheets as efficient cryoprotective agents for the preservation of sensitive biological materials such as sperm, oocytes, and stem cells
Conversion of ozone into hydroxyl radical by granular activated carbon with and without biofilms: Implications for micropollutant abatement
No full textThe transformation of ozone (O-3) into hydroxyl radical ((OH)-O-center dot) during the ozonation was evaluated in the presence of granular activated carbon (GAC) and biofilm-covered granular activated carbon (BGAC). While both GAC and BGAC accelerated O-3 decomposition, the manner in which they generated (OH)-O-center dot was different. GAC catalyzed the conversion of O-3 into (OH)-O-center dot, with increasing hydroxyl radical exposure (integral[(OH)-O-center dot]dt) by 24 -72 % depending on the GAC dose. Conversely, BGAC exhibited limited capacity for (OH)-O-center dot generation from O-3 decomposition, resulting in decreased integral[(OH)-O-center dot]dt by 14 -25 % at higher BGAC doses. This disparity is likely attributable to biofilms on BGAC surface obstructing catalytic sites and hinder O-3-to-(OH)-O-center dot conversion. These different behaviors influenced the degradation of contaminants during ozonation. Specifically, GAC enhanced the degradation of O-3-resistant contaminants, whereas BGAC inhibited it. Machine learning (ML) models were developed based on experimental data to predict oxidant exposures (R-2 > 0.99 for integral[O-3]dt and integral[(OH)-O-center dot]dt). The elimination of several contaminants in systems was successfully predicted by these ML models, coupled with a straightforward kinetic equation that included adsorption and oxidation parameters. Additionally, ozonation modified the catalytic properties of GAC and BGAC. Extended ozonation oxidized GAC surface, diminishing its capability to convert O-3 into (OH)-O-center dot. In contrast, oxidation of BGAC disrupted surface biofilms, thereby restoring its catalytic function.FALSEsciescopu
Microwave-enhanced catalytic degradation of organic compounds with silica-coated iron oxide nanocrystals via fenton-like reaction pathway
No full textMicrowave (MW)-enhanced catalytic oxidation processes are emerging and effective techniques for the degradation of organic compounds in water and wastewater treatment processes. In this study, through applied MW irradiation, monodisperse, superparamagnetic iron oxide nanocrystals (IONCs) with thin, amorphous silica coatings are demonstrated to rapidly catalyze the degradation of organic compounds in water through a thermally enhanced, Fenton−type process. For this, we precisely synthesize amorphous silica-coated various metal oxide (single domain) nanocrystals, and then evaluate the degradation of methyl orange (MO) and benzoic acid (BA), chosen as model organic molecules. We examine (and optimize) the effects of core (nanocrystal) composition, size, and concentration, along with solution pH and hydrogen peroxide (H2O2) concentration. Further, we describe the catalytic degradation of BA with IONCs under MW irradiation through radical scavenger controls and electron paramagnetic resonance (EPR) analysis, which support the proposed reaction mechanism. For materials evaluated, the amorphous silica coating not only prevents the loss of nanocrystal integrity but also provides a reactive, yet stable, interface between nanocrystals and bulk solutions, where the degradation of organic compounds can occur. Synthesized IONCs show high performance, which is repeatable for over five cycles without any deterioration of the nanocrystals core or metal leaching. Taken together, this research highlights the potential of enhanced MW-enhanced oxidation processes appropriately coated (i.e., designed) MW absorbers (here as superparamagnetic IONCs) for advanced water treatment. © The Author(s) 2025.TRUEsciescopu
Network controllability of structured networks: a survey on graph-theoretical approaches
Full text linkThis paper provides an extensive overview of research on the controllability of linear structured networks. In structured networks, the connection weight between agents is characterized as either a fixed zero or any non-zero value, leading to numerous possible realizations. We refer to these non-zero values of connection weights within structured networks as network parameters. Such structured networks exhibit control uncertainty due to variations in network parameters. This paper delves into this aspect, offering insights into how changes in the network parameters affect the controllability of a structured network. By reviewing graph-theoretical results from the past decade, this paper introduces a hierarchical approach to controllability that addresses both entire graphs and individual nodes. Finally, this paper highlights unresolved issues in the field of structured network controllability and suggests future directions. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.TRUEscopu
Advancement of Urea Elimination Using Pre-Halogenation Processes in UV254/Bromine and UV254/Chlorine Systems
No full textAnalysis and mitigation of circulating common mode current in large-scale PCS-integrated ESS sites
No full textThis paper presents an analysis of common mode current (CMC) problems at a large-scale energy storage system (ESS) site with power conversion system (PCS) rated at approximately 80 MW. The site experienced significant troubles such as IGBT damage and sporadic shutdowns, which may be caused by CMCs. A series of measurements were made to find the root cause of the CMC, and the field data were studied through the analysis based on the common mode equivalent circuit. Meanwhile, the variation of the resonance peak of CMC was considered for different operating conditions. As a result, it has been clarified that the main flow path of the CMC includes a wye-connected capacitors (YCAP) installed as an electromagnetic compatibility (EMC) filter. In addition, the parameters of the system could be obtained and applied to the derived equivalent circuit. It has been verified that the frequency analysis results via Bode plot and field measurement were in close agreement. Finally, the hardware-in-the-loop simulation (HILS) was executed with the derived parameters. The HILS results strongly aligned with the actual measurements, confirming the accuracy of the simulation model. Finally, the preview hardware-in-the-loop (HIL) test showed that the elimination of YCAP significantly reduces the CMC. The effectiveness of YCAP removal was also shown in the field. This study could provide valuable guidance for addressing similar issues that may arise in future large-scale ESS installations
Effects of Acupuncture on the mRNA Expression of NF-кB p65/TNF-α Activated by Fat Accumulation in High-fat Diet-induced Nonalcoholic Fatty Liver Disease Rats
No full textBackground: We studied the effects of manual acupuncture (MA) and warm acupuncture (WA) on early-stage nonalcoholic steatohepatitis in relation to fat accumulation by observing the mRNA expression of nuclear factor-κB (NF-κB) p65 and tumor necrosis factor-α (TNF-α) in a rat model with nonalcoholic fatty liver disease (NAFLD) induced by high-fat diet. Methods: The experiment was performed using Sprague Dawley rats randomly divided into control (CON), NAFLD, NAFLD + MA and NAFLD + WA groups. Acupuncture was performed on the SP9 + BL18 acupoint from each group for 5 min, twice a week for 8 weeks. Total cholesterol (TC) was measured in the serum and triglyceride (TG) and resistin were measured in the hepatic tissue. In addition, hematoxylin and eosin stain, Masson’s trichrome stain, Oil red O stain and perilipin immunohistochemistry were used for histological analysis. Finally, quantitative polymerase chain reactions were performed to observe the changes in TLR4, NF-κB p65 and TNF-α. Result: Resitin and TLR4 decreased in the NAFLD + WA group. The NAFLD + MA group exhibited reduced levels of TC and TG, which mitigated NF-κB p65 and TNF-α mRNA downregulation through downregulation of the TLR4. © 2025 Agricultural Research Communication Centre. All rights reserved.TRUEsciescopu
Neural Dynamics of Group Interaction in the Iterate Multi-player Prisoner’s Dilemma Game: Multilayer Network Approach
No full textUnderstanding social interaction from various human behaviors is a complex task. Hyperscanning research tackles this challenge by delving into behavioral mechanisms through a neuroscience lens. While traditional studies focus on inter-brain synchrony in paired functional brain networks, they often lack methods for measuring interactions at the group level. In this study, we propose a multilayer network approach to estimate group brain synchrony and gain deeper insights into the brain’s intricate organization. By utilizing the Prisoner’s Dilemma Game, our goal is to find group interaction processes through distinct behaviors such as cooperation and defection. Thus, the inter-brain synchrony along with differences in network connectivity and structural properties within the functional group network were statistically analyzed between cooperation and defection. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025
Ad hoc calibration of interferometric system for measuring nanometer-scale displacements induced by laser ultrasound
No full textLaser Ultrasound (LUS) is commonly used in many fields including thickness measurement and defect inspection. In a conventional LUS system, a piezo-based transducer (PZT) is generally used for detecting the ultrasound echo waves, which requires direct contact with a specimen and thus prolongs measurement time when any lateral scanning is necessary. We present a novel non-contact interferometric system based on a 3 × 3 optical fiber coupler. Even though the 3 × 3 interferometric system works stably at any operating point and allows quantitative measurements, it is generally known that careful calibration is necessary before main measurements. Experimentally, it was observed that the surface displacement, induced by the ultrasound wave of LUS, of a cornea phantom was so minute that averaging was necessary. In this study, we discovered that by using the multiple data sets acquired for averaging, we could obtain the system ad hoc characteristic ellipse without performing the conventional calibration process. Furthermore, by utilizing coherent average we could extract the displacement with a 0.14 nm sensitivity. We could also measure the thickness variation, induced by ocular pressure, of the cornea phantom with a resolution of 4.3 μm by measuring the time of a round trip of the ultrasound wave. This straightforward system, composed solely of a 3 × 3 coupler, is expected to promise a compact and efficient solution to diverse applications. © 2024 The AuthorsTRUEsciescopu