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116
- 작성자박은영
- 작성일2025-02-28
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Dual-biased metal oxide electrolyte-gated thin-film transistors for enhanced protonation in complex biofluidsby Hwang, Chuljin;Song, Yoonseok;Baek, Seokhyeon;Choi, Jun-Gyu;Park, SungjunScientific Reports 2024, 14, 30772; https://doi.org/10.1038/s41598-024-80005-0AbstractpH sensing technology is pivotal for monitoring aquatic ecosystems and diagnosing human health conditions. Indium–gallium–zinc oxide electrolyte-gated thin-film transistors (IGZO EGTFTs) are highly regarded as ion-sensing devices due to the pH-dependent surface chemistry of their sensing membranes. However, applying EGTFT-based pH sensors in complex biofluids containing diverse charged species poses challenges due to ion interference and inherently low sensitivity constrained by the Nernst limit. Here, we propose a dual-biased (DB) EGTFT pH sensing platform, acquiring back-gate-assisted sensitivity enhancement and recyclable redox-coupled protonation at the semiconductor-biofluid interface. A solution-processed amorphous IGZO film, used as the proton-sensitive membrane, ensures scalable uniformity across a 6-inch wafer. These devices demonstrate exceptional pH resistivity over several hours when submerged in solutions with pH levels of 4 and 8. In-depth electrochemical investigations reveal that back-gate bias significantly enhances sensitivity beyond the Nernst limit, reaching 85 mV/pH. This improvement is due to additional charge accumulation in the channel, which expands the sensing window. As a proof of concept, we observe consistent variations in threshold voltage during repeated pH cycles, not only in standard solutions but also in physiological electrolytes such as phosphate-buffered saline (PBS) and artificial urine, confirming the potential for reliable operation in complex biological environments.
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114
- 작성자박은영
- 작성일2025-02-28
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Skin Structure and Physiology in Transdermal Drug Deliveryby Sofia Brito, Moonki Baek, Bum-Ho BinPharmaceutics 2024, 16(11), 1403; https://doi.org/10.3390/pharmaceutics16111403AbstractSeveral industries are increasingly focused on enhancing the delivery of active ingredients through the skin to optimize therapeutic outcomes. By facilitating the penetration of active ingredients through the skin barrier, these enhancers can significantly improve the efficacy of various formulations, ranging from skincare products to therapeutic agents targeting systemic circulation. As the understanding of skin physiology and the mechanisms of drug absorption deepen, these industries are adopting permeation enhancers more widely, ultimately leading to better patient outcomes and expanded treatment options. However, the structure and physiological function of the skin can vary according to different factors, such as the area of the body and between individuals. These variations, along with external environmental exposures, aging and pathological conditions, introduce complexities that must be carefully considered when designing effective delivery systems. Considering the intricacies of skin structure and physiology, tailoring systems to account for regional differences, individual variability, and changes induced by environmental factors or disease is critical to optimizing therapeutic outcomes. This review discusses the features of skin structure, physiology, and pathologies, as well as the application of permeation enhancers in these contexts. Furthermore, it addresses the use of animal skin models in transdermal delivery and dermatological studies, along with the latest developments in this field.Keywords: skin structure; skin physiology; skin disease; skin aging; skin models; transdermal drug delivery
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112
- 작성자박은영
- 작성일2025-02-28
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Fabrication of a uniform quantum dot film with a high quantum yieldby Min Woo Oh, Byung Hee Son, Jee Sang Yoon, Yonghwan Yoo, Yongduk Kim, Soo Bong Choi, Yeong Hwan Ahn, Won Bae Cho, Doo Jae ParkNanotechnology 2024, 36(3), 35705; https://doi.org/10.1088/1361-6528/ad86c6AbstractWe present a method that uses viscosity-lowering materials to fabricate flexible polydimethylsiloxane-based quantum dot (QD) films with high quantum yield (QY) and improved uniformity. We found that the aggregation of individual QDs was prevented, and the QY improved simultaneously in films that contained surfactants. These films showed an improved absorption of approximately 27% in the near-UV and blue light regions, along with an improved photoluminescence of approximately 18%, indicating improved light conversion from the UV to the visible frequency region.
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110
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- 작성일2025-02-28
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Metamaterial Sensing of Cyanobacteria Using THz Thermal Curve Analysisby Jeong, Tae Hee;Jun, Seung Won;Ahn, Yeong HwanBiosensors 2024, 14(11), 519; https://doi.org/10.3390/bios14110519AbstractIn this study, we perform thermal curve analyses based on terahertz (THz) metamaterials for the label-free sensing of cyanobacteria. In the presence of bacterial films, significant frequency shifts occur at the metamaterial resonance, but these shifts become saturated at a certain thickness owing to the limited sensing volume of the metamaterial. The saturation value was used to determine the dielectric constants of various cyanobacteria, which are crucial for dielectric sensing. For label-free identification, we performed thermal curve analysis of THz metamaterials coated with cyanobacteria. The resonant frequency of the cyanobacteria-coated metasensor changed with temperature. The differential thermal curves (DTC) obtained from temperature-dependent resonance exhibited peaks unique to individual cyanobacteria, which helped identify individual species. Interestingly, despite being classified as Gram negative, cyanobacteria exhibit DTC profiles similar to those of Gram-positive bacteria, likely due to their unique extracellular structures. DTC analysis can reveal unique characteristics of various cyanobacteria that are not easily accessible by conventional approaches.Keywords: terahertz; cyanobacteria; metamaterials
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108
- 작성자박은영
- 작성일2025-02-28
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Cost-Effective Synthesis of Unsymmetric Tetrazinesby Jiwon Hwang, Byeongjip Yoon, Sung-Eun SuhBulletin of the Korean Chemical Society 2024, 45, 867-872; https://doi.org/10.1002/bkcs.12903Abstract1,2,4,5-Tetrazines serve as versatile two-carbon synthons, essential for synthesizing a variety of (hetero)aromatic compounds. Their specific reactivity with certain dienophiles, without interfering with biochemical processes, makes them ideal for bioorthogonal ligation. Despite their broad utility, current synthetic methods are costly and raise safety concerns, particularly during scale-up. This study introduces safer and more cost-effective synthetic strategies utilizing zinc chloride or boron trifluoride diethyl etherate as catalysts. These alternatives significantly reduce costs and enhance safety, potentially expanding the applicability of tetrazine synthesis across broader research domains.Keywords: formamidine; hydrazine; Lewis acid; nitrile; tetrazine
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106
- 작성자박은영
- 작성일2025-02-28
- 28
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Aryne Chemistry: Generation Methods and Reactions Incorporating Multiple Arynesby Nayoung Kim;Myungsoo Choi;Sung-Eun Suh;David M. ChenowethChemical Reviews 2024, 124, 11435–11522; https://doi.org/10.1021/acs.chemrev.4c00296AbstractArynes hold significance for the efficient fusion of (hetero) arenes with diverse substrates, advancing the construction of complex molecular frameworks. Employing multiple equivalents of arynes is particularly effective in the rapid formation of polycyclic cores found in optoelectronic materials and bioactive compounds. However, the inherent reactivity of arynes often leads to side reactions, yielding unanticipated products and underlining the importance of a detailed investigation into the use of multiple arynes to fine-tune their reactivity. This review centers on methodologies and syntheses in organic reactions involving multiple arynes, categorizing based on mechanisms like cycloadditions, σ-bond insertions, nucleophilic additions, and ene reactions, and discusses aryne polymerization. The categorization based on these mechanisms includes two primary approaches: the first entails multiple aryne engagement within a single step while the second approach involves using a single equivalent of aryne sequentially across multiple steps, with both requiring strict reactivity control to ensure precise aryne participation in each respective step. Additionally, the review provides an in-depth analysis of the selection of aryne precursors, organized chronologically and by activation strategy, offering a comprehensive background that supports the main theme of multiple aryne utilization. The expectation remains that this comprehensive review will be invaluable in designing advanced syntheses engaging multiple arynes.Subjects: Addition reactions; Anions; Hydrocarbons; Precursors; Salts
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104
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- 작성일2025-02-28
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Anomalous Reaction Pathways to Methane Production in Photocatalytic Ethanol Oxidationby Azam Nasirian, Kihyuk Sung, Hye-Young Jang, Sungju YuACS Applied Materials & Interfaces 2024, 16(39), 52191-52199; https://doi.org/10.1021/acsami.4c08729AbstractPhotocatalytic reduction reactions occasionally utilize sacrificial agents to scavenge photogenerated holes, thus enhancing the kinetics and efficiency of electron harvesting. However, exploring alternative hole-mediated oxidation reactions and their potential impact on photoredox processes is limited. This study investigates the products resulting from the oxidation of ethanol, a commonly used hole scavenger, and the underlying mechanisms involved. We examine a homogeneous eosin Y photoreaction scheme containing a Cu complex coordinated with an N-heterocyclic carbene, a combination often employed in CO2 conversion. Under visible-light excitation, this photosystem yields methane as an unusual product, alongside acetaldehyde and carbon monoxide. Mechanistic analysis reveals that ethanol undergoes a catalytic cascade involving oxidative processes, C–C bond cleavage, and intermolecular hydrogen atom transfer. Notably, the Lewis-acidic metal center of the Cu complex activates a novel pathway for ethanol oxidation. This work presents the influence of catalyst selection and reaction condition optimization on the emergence of new or unexpected catalytic processes.Keywords: Eosin Y; photocatalysis; HAT; sacrificial electron donor; hole scavenger
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102
- 작성자박은영
- 작성일2025-02-28
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Coupling between electrons and charge density wave fluctuation and its possible role in superconductivityby Lee, Yeonghoon; Sur, Yeahan; Kim, Sunghun; Cha, Jaehun; Hyun, Jounghoon; Lim, Chan-young; Hashimoto, Makoto; Lu, Donghui; Kim, Younsik; Huh, Soonsang; Kim, Changyoung; Ideta, Shinichiro; Tanaka, Kiyohisa; Kim, Kee Hoon; Kim, YeongkwanAdvanced Science 2024, 11(41), 2406043; https://doi.org/10.1002/advs.202406043AbstractIn most charge density wave (CDW) systems of different material classes, ranging from traditional correlated systems in low-dimension to recent topological systems with Kagome lattice, superconductivity emerges when the system is driven toward the quantum critical point (QCP) of CDW via external parameters of doping and pressure. Despite this rather universal trend, the essential hinge between CDW and superconductivity has not been established yet. Here, the evidence of coupling between electron and CDW fluctuation is reported, based on a temperature- and intercalation-dependent kink in the angle-resolved photoemission spectra of 2H-PdxTaSe2. Kinks are observed only when the system is in the CDW phase, regardless of whether a long- or short-range order is established. Notably, the coupling strength is enhanced upon long-range CDW suppression, albeit the coupling energy scale is reduced. Interestingly, the estimation of the superconducting critical temperature by incorporating the observed coupling characteristics into McMillan's equation yields results closely resembling the known values of the superconducting dome. The results thus highlight a compelling possibility that this new coupling mediates Cooper pairs, which provides new insights into the competing relationship not only for CDW but also for other competing orders.Keywords: angle-resolved photoemission spectroscopy; charge density wave; superconductivity
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100
- 작성자박은영
- 작성일2025-02-28
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Bijections on pattern avoiding inversion sequences and related objectsby JiSun Huh, Sangwook Kim, Seunghyun Seo, and Heesung ShinAdvances in Applied Mathematics 2024, 161, 102771; https://doi.org/10.1016/j.aam.2024.102771AbstractThe number of inversion sequences avoiding two patterns 101 and 102 is known to be the same as the number of permutations avoiding three patterns 2341, 2431, and 3241. This sequence also counts the number of Schröder paths without triple descents, restricted bicolored Dyck paths, (101, 021)-avoiding inversion sequences, and weighted ordered trees. We provide bijections to integrate them together by introducing F-paths. Moreover, we define three kinds of statistics for each of the objects and count the number of each object with respect to these statistics. We also discuss direct sums of each object.Keywords: Schröder paths; Permutations; Inversion sequences; Ordered trees; Pattern avoidance; Direct sum
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98
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- 작성일2025-02-28
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- 동영상동영상
[논문] 권순선, 안수현 - Enhanced trajectory data visualization: a dynamic time warping integrated t-SNE approach with ... 위치 확인
