DGIST Scholar는 학술문화팀에서 운영하는 기관 리포지터리로, 학술정보 공유와 글로벌 확산을 위해 DGIST에서 생산되는 학술성과물(논문, 프로시딩, 학위논문, 특허, 연구보고서 등)을 수집, 관리하는 Open Access 디지털 저장소입니다.
Magnetic and pH-Sensitive dual actuation of biohybrid microswimmer of targeted drug release suitable for cancer cell microenvironment
2025-06Journal of Science: Advanced Materials and Devices, v.10, no.2
The chemotherapeutic agents most frequently used in cancer treatment often have limited effectiveness because of their low specificity for tumors and poor therapeutic performance. In addition to the aforementioned therapeutic challenges the drug delivery carriers conjugated with the drug encounter early detection and elimination from the immune system before arriving at the affected area continues to be a significant research focus among researchers. To address this prevalent issue, an effective approach has been developed that leverages the physiological differences between normal and tumor tissue to enhance the efficacy of anticancer drugs. This drug delivery system is designed based on pH-sensitive drug release, ensuring targeted release within cancer cells. In the present study, we have developed a drug carrier called as biohybrid magnetic microswimmer (BMM). The BMM was formed through a three-step process: firstly, bacterial surfaces were functionalized with biotinylated PEG which enables the bacteria to escape the phagocytosis process; secondly, the anticancer drug lenalidomide was PEGylated to enhance solubility; and finally, both complexes were conjugated via streptavidin-biotin interaction. The study investigated bond formation, bacterial viability after drug treatment, pH-dependent release, and cytotoxicity in various cell lines (MCF-7 and THP-1 cells), and the results revealed that the concentration of the drug, released from BMM gradually increased as the pH of the solvent decreased from neutral to acidic, mimicking the surrounding environment of normal cells and cancer cells, respectively, which in turn affects the cancer cell viability negatively. Therefore, BMM shows promise in targeted drug delivery, utilizing magnetic manipulation and pH-triggered release, providing advantages that include bacteria's maneuverability and PEG's stealth properties, enhancing drug efficacy. © 2025 Vietnam National University, Hanoi
Twist-Induced Dimensional Crossover and Topological Phase Transitions in Bismuthene Quasicrystals
ACCEPTChemistry of Materials
Twisted bismuthene homojunctions, comprised of a Bi(111) bilayer atop two Bi(110) monolayers, exhibit a distinct growth orientation that is facilitated by self-assembly. Our cross-sectional structural analysis reveals an unexpected growth alignment of Bi(110) layers on transition-metal dichalcogenides, deviating from the anticipated Bi(111) bilayer structure. This self-assembly process, driven by the crystal symmetry interplay, induces a topological phase transition beyond a critical thickness. The dimensional crossover in the Fermi surfaces marks the electronic transition from two-dimensional (2D) Bi(110) to 1D Bi(111) quasicrystals. Additionally, the emergence of the topologically nontrivial band structures, an enhanced 1D carrier density, and a metal-insulator transition through band inversion indicate that the twisted bismuthene quasicrystals are promising candidates for higher-order topological quasicrystalline insulators. These findings pave the way for low-resistance contacts in 2D transistors, advancing the development of next-generation electronic devices. © 2025 American Chemical Society.
An Overview of Flame-Retardant Materials for Triboelectric Nanogenerators and Future Applications
2025-03Advanced Materials, v.37, no.9
Triboelectric nanogenerators (TENGs) have gained significant attention for ability to convert mechanical energy into electrical energy. As the applications of TENG devices expand, their safety and reliability becomes priority, particularly where there is risk of fire or spontaneous combustion. Flame-retardant materials can be employed to address these safety concerns without compromising the performance and efficiency of TENGs. The primary focus of this review is on flame-retardant materials, including polymers, biomaterials, liquid polymers, aerogels, and carbon-based materials. The fundamental properties of these materials for TENG applications are elucidated. The characteristics of each material type are described, along with their potential to boost the safety and performance of TENGs. The importance of flame retardancy in advancing TENG technology can be projected from its usage in wearable electronics, self-powered sensors, and smart textiles. Current challenges such as material compatibility, fabrication complexity, and environmental concerns are addressed, along with proposed strategies for overcoming them. This review underscores the significance of flame-retardant materials in strengthening the functionality and safety of TENG devices, paving the way for their widespread adoption across various industries. © 2025 Wiley-VCH GmbH.
Miniature Li+ solvation by symmetric molecular design for practical and safe Li-metal batteries
ACCEPTNature Energy
Developing high-safety Li-metal batteries (LMBs) with rapid rechargeability represents a crucial avenue for the widespread adoption of electrochemical energy storage devices. Realization of LMBs requires an electrolyte that combines non-flammability with high electrochemical stability. Although current electrolyte technologies have enhanced LMB cyclability, rational electrolyte fabrication capable of simultaneously addressing high-rate performance and safety remains a grand challenge. Here we report an electrolyte design concept to enable practical, safe and fast-cycling LMBs. We created miniature anion–Li+ solvation structures by introducing symmetric organic salts into various electrolyte solvents. These structures exhibit a high ionic conductivity, low desolvation barrier and interface stabilization. Our electrolyte design enables stable, fast cycling of practical LMBs with high stability (LiNi0.8Co0.1Mn0.1O2 cell (twice-excessed Li): 400 cycles) and high power density (pouch cell: 639.5 W kg−1). Furthermore, the Li-metal pouch cell survived nail penetration, revealing its high safety. Our electrolyte design offers a viable approach for safe, fast-cycling LMBs. © The Author(s), under exclusive licence to Springer Nature Limited 2025.
Hybridized nanogenerators: Materials and structural design for improving energy harvesting
ACCEPTMRS Bulletin
As technology advances and enhances modern lifestyles, energy consumption is increasing dramatically. Harnessing energy from ambient sources—such as light, water, wind, and mechanical forces—presents a promising and eco-friendly method for converting renewable energy into usable electrical power. Recent developments in nanogenerators have led to the creation of hybridized nanogenerators, significantly improving overall power generation and providing sufficient energy to support electronic devices essential to today’s technology-driven lifestyle. The latest developments in hybrid nanogenerators are reviewed in this article, with a focus on material fabrication and architectural designs; particularly, emphasis is placed on multifunctional materials capable of harvesting multiple forms of energy. © The Author(s), under exclusive License to the Materials Research Society 2025.
Utility of hypervariable region in hepatitis E virus for genetic evolution analysis and epidemiological studies
2025-02Journal of General Virology, v.106, no.2
Clinical and experimental studies have advanced our understanding of hepatitis E virus (HEV) infection; however, translating the findings to improve prevention and clinical outcomes remains challenging. Phylogenetic analyses of HEV show inconsistencies due to variations in the nucleotide regions studied. This study examined specific HEV regions to facilitate comprehensive molecular and phylogenetic analyses by examining the complete genome and commonly studied partial genome regions. We compared topological similarities between phylogenetic trees and evaluated evolutionary divergence using base substitutions and pairwise distances. The hypervariable region (HVR) showed the closest topology (Robinson–Foulds, Jaccard Robinson–Foulds and clustering information) to the complete genome and a higher mutation rate, resulting in longer branch lengths and clearer genotypic distinctions. Pairwise analysis revealed greater intra- and intergenotypic diversity in the HVR than in other regions. The higher base substitution rate and longer branch lengths of HVR suggest its key role in genotype evolution. Classifying HEV using HVR instead of the other partial genomic regions can reveal subtypes that more accurately reflect the genetic characteristics of HEV. Future research could focus on HVRs to better compare clinical symptoms and genetic features of HEV. © 2025 The Authors.
Construction of NiCoO2-(Ni,Co)Se2 hybrid nanorods as an effective bifunctional interlayer for lithium‑sulfur batteries
2025-03Journal of Energy Storage, v.113
The practical application of lithium‑sulfur (Li[sbnd]S) batteries is hindered by the shuttle effect caused by the dissolution of polysulfides in the electrolyte during the charge-discharge process, and the sluggish kinetic conversion of polysulfides. In this work, we present a novel hybrid material, nanorod-shaped NiCoO2-(Ni,Co)Se2 hybrid (NCOSe), synthesized through simple hydrothermal and further selenization methods. These NCOSe hybrid nanorods were uniformly coated onto a commercial polypropylene (PP) separator via vacuum filtration for application in Li[sbnd]S batteries. In the hybrid structure, the NiCoO2 nanorod component exhibits strong polysulfides adsorption due to its high polarity, while (Ni,Co)Se2 part promotes favorable polysulfides conversion due to superb catalytic conversion properties. Electrochemical testing reveals that the Li[sbnd]S full cell with the bifunctional NCOSe/PP separator delivers an initial specific capacity of 1277 mAh g−1 at a current density of 0.1C (1C = 1675 mA g−1). After 200 cycles at 0.2C, the specific capacity reaches 793 mAh g−1, with a low average capacity decay of just 0.123 % per cycle. With a higher sulfur loading of 3.0 mg cm−2, the cell achieves a specific capacity of 455 mAh g−1 after 220 cycles at 0.5C, and with a maximum sulfur loading of 4.4 mg cm−2 at 0.5C, it still maintains 72 % (311 mAh g−1) of its initial capacity after 400 cycles. This study introduces a novel hybrid material with dual functionalities-enhanced polysulfides adsorption and accelerated polysulfides conversion, offering improved cycling stability of Li[sbnd]S batteries. © 2025 Elsevier Ltd
Regioselective Formal Hydroamidation of Alkynes: Synthesis of α-Substituted Acrylamides
ACCEPTEuropean Journal of Organic Chemistry
The formal hydroamidation of alkyne is a powerful synthetic method that enables the formation of various α,β-unsaturated amides. In this article, the efficient formal hydroamidation of terminal and internal alkynes is described, which constitutes the Ni-catalyzed α-selective hydroalumination of alkynes and subsequent treatment with isocyanates. This method is gram-scalable and the synthetic utility is highlighted by the synthesis of a β-lactam from α-phenyl acrylamide. © 2025 Wiley-VCH GmbH.
A highly sensitive disease pre-screening approach for glycosuria: Triboelectric sensing at the liquid-solid interface
2025-03Chemical Engineering Journal, v.508
Prescreening and disease detection offer significant benefits in the prevention of serious illnesses. Traditional screening methods for disease identification have been complex and expensive, often requiring invasive procedures, which can be both harmful and uncomfortable. To address these limitations, various non-invasive screening technologies have been developed. Among recent innovations, the liquid–solid interface concept has emerged as a promising avenue for nanogenerator applications, enabling the harvesting and sensing of liquid energy and substances. In this study, we introduce a liquid–solid interface triboelectric sensor (LS-TES) for non-invasive disease screening and sensing. The LS-TES, utilizing a double-electrode configuration, delivers an immediate electrical response upon droplet contact with the solid surface and top electrode. In the case of urine glucose monitoring, our findings demonstrate a significant reduction in electrical signals with increasing concentrations of glucose, as glucose molecules hinder electron transfer from water to the solid surface, thereby disrupting the formation of the electrical double layer at the liquid–solid interface. The sensor exhibits excellent glucose sensing performance within a concentration range of 0.2 mM to 14 mM, with a detection limit of 0.25 mM and a rapid response time of 5–10 s. The LS-TES is cost-effective, highly stable, and reusable, maintaining consistent electrical responses across ten cycles of alternating droplet measurements. This work presents a preclinical assessment approach, specifically for urine glucose monitoring, utilizing an innovative sensor based on the liquid–solid interface. The proposed concept has the potential to serve as an individual indicator for early medical symptom detection, offering relief to a large number of patients. © 2025 Elsevier B.V.
Effects of artificial interior stone (AIS) sludge incorporation on strength enhancement of cement mortar after exposed to elevated temperatures
2025-07Case Studies in Construction Materials, v.22
There has been increasing interest in developing recycling strategies for artificial interior stone (AIS) sludge in light of climate change, carbon neutrality objectives, and environmental concerns. In this study, a recycling strategy that incorporates AIS sludge into the production of interior and exterior wall materials with high early strengths is newly proposed. Additionally, this research is the first, to our knowledge, to investigate the thermo-mechanical properties of AIS sludge-incorporated cement mortar following exposure to elevated temperatures. Initially, the early strength of specimens was compared under three different curing conditions (i.e., air at 25°C and 60°C, and water at 90°C) to identify the optimal curing conditions. Subsequently, the specimens were exposed to elevated temperatures of 400, 600, and 800°C, and their strength degradation was assessed. The results were thoroughly analyzed using X-ray diffraction (XRD), thermogravimetric analysis (TGA), and permeable void measurements. The experimental results revealed a reduction in density of approximately 15 % across all specimens. Furthermore, the normalized specific flexural strength exhibited a significant increase, with improvements exceeding 800 % after exposure to a temperature of 800°C. The findings revealed that AIS sludge, when used as a replacement for sand in cement mortar, offers significant potential for producing lightweight, high-strength wall panels capable of withstanding elevated temperatures. © 2025 The Authors
SoN: Selective Optimal Network for smartphone-based indoor localization in real-time
2025-05Expert Systems with Applications, v.272
Deep learning-based scene recognition algorithms have been developed for real-time application in indoor localization systems. However, owing to the slow calculation time resulting from the deep structure of convolutional neural networks, deep learning-based algorithms have limitations in the usage of real-time applications, despite their high accuracy in classification tasks. To significantly reduce the computation time of these algorithms and slightly improve their accuracy, we thus propose a path-selective deep learning network, denoted as Selective Optimal Network (SoN). The SoN selectively uses the depth-variable networks depending on a new indicator, denoted as the classification-complexity of a source image. The SoN reduces the prediction time by selecting optimal depth for the baseline networks corresponding to the input samples. The network was evaluated using two public datasets and two custom datasets for indoor localization and scene classification, respectively. The experimental results indicated that, compared to other deep learning models, the SoN exhibited improved accuracy and enhanced the processing speed by up to 78.59%. Additionally, the SoN was applied to a smartphone-based indoor positioning system in real-time. The results indicated that the SoN shows excellent performance for rapid and accurate classification in real-time applications of indoor localization systems. © 2025
Gintonin Binds to Reduced LPA4 Receptor Subtype in Human Cortical Neurons in Alzheimer's Disease Brains
2025-02Biomolecules, v.15, no.2
Ginseng, a traditional herbal medicine with a long history of use, is known to support human health, particularly by influencing brain function. Recent studies have identified gintonin, a lysophosphatidic acid (LPA) receptor ligand derived from ginseng, as a key bioactive. However, the specific LPA receptor subtypes targeted by gintonin in the human brain to exert its anti-Alzheimer’s (AD) effects remain unclear. This study aimed to elucidate the LPA receptor subtype targeted by gintonin in the human cortex. Using a fluorescent gintonin conjugate, we investigated receptor binding in cortical samples from healthy individuals (n = 4) and AD patients (n = 4). Our results demonstrated that fluorescent gintonin selectively binds to human cortical neurons rather than glial cells and that gintonin-binding sites are co-localized with the LPA4 receptor subtype. Furthermore, the expression of LPA4 receptors was significantly reduced in the cortical neurons of AD patients. These results suggest that the LPA4 receptor may serve as a novel histopathological marker for AD and represent a promising therapeutic target for gintonin-based prevention and treatment strategies. © 2025 by the authors.