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中国有色金属学会会刊：英文版 2009年第4期19卷 824-828页

作者： jin-young cho Duck-young HWANG Dong-H eon LEE Bongyoung YOO Dong-Hyuk SHIN Department of Metallurgy and Materials Scienc e Hanyang University

The effect of potassium pyrophosphate in the electrolyte on plasma electrolytic oxidation(PEO) process for AZ91 Mg alloy was *** morphologies and chemical compositions of the coating layer on the AZ91 Mg alloy were evaluated and corrosion resistance was also estimated by potentiodynamic polarization *** coating layer on AZ91 Mg alloy coated from the Bath 2 containing 0.03 mol/L of potassium pyrophosphate for 360 s exhibited considerably dense structure and contained 11%-18%(mass fraction) of *** higher content of phosphorous of coating layer coated from Bath 2 could be detected at the bottom of oxide layer,which strongly implied that the phosphorous ion might be concentrated at the barrier *** potential of coating layer of AZ91 Mg alloy increased and corrosion current density decreased with increasing the concentration of potassium *** polarization resistance(Rp) of coating layer of AZ91 Mg alloy coated from Bath 2 was 4.65×107 Ω/cm2,which was higher than that(Rp=3.56×104 Ω/cm2) of the sample coated from electrolyte without potassium *** coating layer coated from Bath 2 containing 0.03 mol/L potassium pyrophosphate exhibited the best corrosion resistance.

关键词： AZ91镁合金合金涂层焦磷酸钾电解氧化等离子体电解质腐蚀电流密度耐腐蚀性

A New Encryption Mechanism Supporting the Update of Encrypted Data for Secure and Efficient Collaboration in the Cloud Environment

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 813-834页

作者： Chanhyeong cho Byeori Kim Haehyun cho Taek-young Youn Department of Cyber Security Dankook UniversityYongin16890Republic of Korea Department of Software Soongsil UniversitySeoul07027Republic of Korea

With the rise of remote collaboration,the demand for advanced storage and collaboration tools has rapidly ***,traditional collaboration tools primarily rely on access control,leaving data stored on cloud servers vulnerable due to insufficient *** paper introduces a novel mechanism that encrypts data in‘bundle’units,designed to meet the dual requirements of efficiency and security for frequently updated collaborative *** bundle includes updated information,allowing only the updated portions to be reencrypted when changes *** encryption method proposed in this paper addresses the inefficiencies of traditional encryption modes,such as Cipher Block Chaining(CBC)and Counter(CTR),which require decrypting and re-encrypting the entire dataset whenever updates *** proposed method leverages update-specific information embedded within data bundles and metadata that maps the relationship between these bundles and the plaintext *** utilizing this information,the method accurately identifies the modified portions and applies algorithms to selectively re-encrypt only those *** approach significantly enhances the efficiency of data updates while maintaining high performance,particularly in large-scale data *** validate this approach,we conducted experiments measuring execution time as both the size of the modified data and the total dataset size *** show that the proposed method significantly outperforms CBC and CTR modes in execution speed,with greater performance gains as data size ***,our security evaluation confirms that this method provides robust protection against both passive and active attacks.

关键词： Cloud collaboration mode of operation data update efficiency

High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation

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Neural Regeneration Research 2025年第1期20卷 107-115页

作者： Hanki Kim Bum Jun Kim Seungyon Koh Hyo jin cho Xuelian jin Byung Gon Kim Jun young choi Department of Brain Science Ajou University School of MedicineSuwonSouth Korea Department of Biomedical Sciences Ajou University Graduate School of MedicineSuwonSouth Korea Department of Neurology Ajou University School of MedicineSuwonSouth Korea Department of Geriatrics The Affiliated Suqian First People’s Hospital of Nanjing Medical UniversitySuqianJiangsu ProvinceChina

High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and ***-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain *** drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system *** it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system *** this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory *** targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1.

关键词： central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 inflammation neural stem cells neurodevelopment oligodendrocyte progenitor cells redox status regeneration

Current guidelines for Helicobacter pylori treatment in East Asia 2022:Differences among China,Japan,and South Korea

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World Journal of Clinical Cases 2022年第19期10卷 6349-6359页

作者： Jun-Hyung cho So-young jin Digestive Disease Center Soonchunhyang University HospitalSeoul 04401South Korea Department of Pathology Soonchunhyang University HospitalSeoul 04401South Korea

Helicobacter pylori (H. pylori) infection is highly prevalent in East Asia. The overallseroprevalence rate of H. pylori infection is 44.2% in China, 37.6%-43.2% in Japan,and 51.0% in South Korea. H. pylori can cause peptic ulcer disease and gastriccancer. East Asian countries have high rates of gastric cancer (age-standardizedincidence rate: 20-30 per 100000). The Kyoto global consensus report emphasizedthat H. pylori gastritis should be considered the main cause for the development ofgastric cancer. H. pylori treatment guidelines in China, Japan, and South Koreahave recently been revised according to data from each of those ***, emerging antibiotic resistance is an important barrier to H. pylorieradication. The recommended H. pylori treatment regimens differ among thosethree East Asian countries. In this review, recent guidelines and up-to-dateresearch on H. pylori treatment regimens from China, Japan, and South Korea arediscussed.

关键词： Helicobacter pylori Treatment Antibiotic resistance China Japan South Korea

Super-resolution localization photoacoustic microscopy using intrinsic red blood cells as contrast absorbers

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Light(Science & Applications) 2019年第1期8卷 212-222页

作者： Jongbeom Kim jin young Kim Seungwan Jeon jin Woo BAIK Seong Hee cho Chulhong Kim Departments of Creative IT Engineering Electrical EngineeringMechanical Engineeringand Interdisciplinary Bioscience and BioengineeringPohang University of Science and Technology(POSTECH)77 Cheongam-roNam-guPohangGyeongbuk 37673Republic of Korea

Photoacoustic microscopy(PAM)has become a premier microscopy tool that can provide the anatomical,functional,and molecular information of animals and humans in ***,conventional PAM systems suffer from limited temporal and/or spatial ***,we present a fast PAM system and an agent-free localization method based on a stable and commercial galvanometer scanner with a custom-made scanning mirror(L-PAM-GS).This novel hardware implementation enhances the temporal resolution significantly while maintaining a high signal-to-noise ratio(SNR).These improvements allow us to photoacoustically and noninvasively observe the microvasculatures of small animals and humans in ***,the functional hemodynamics,namely,the blood flow rate in the microvasculature,is successfully monitored and quantified in *** importantly,thanks to the high SNR and fast B-mode rate(500 Hz),by localizing photoacoustic signals from captured red blood cells without any contrast agent,unresolved microvessels are clearly distinguished,and the spatial resolution is improved by a factor of 2.5 in ***-GS has great potential in various fields,such as neurology,oncology,and pathology.

关键词： resolution absorber scanner

Beta-nerve growth factor gene therapy alleviates pyridoxine-induced neuropathic damage by increasing doublecortin and tyrosine kinase A in the dorsal root ganglion

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Neural Regeneration Research 2020年第1期15卷 162-168页

作者： Hyun-Kee cho Woosuk Kim Kwon-young Lee jin-Ok Ahn Jung Hoon choi In Koo Hwang jin-young Chung Department of Veterinary Internal Medicine and Institute of Veterinary Science College of Veterinary MedicineKangwon National UniversityChuncheonKangwon-doSouth Korea Department of Anatomy and Cell Biology College of Veterinary MedicineResearch Institute for Veterinary ScienceSeoul National UniversitySeoulSouth Korea Department of Anatomy College of Veterinary MedicineKangwon National UniversityChuncheonKangwon-doSouth Korea

Beta-nerve growth factor(β-NGF) is known to be a major leading cause of neuronal plasticity. To identify the possible action mechanisms of β-NGF gene therapy for sciatic nerve recovery, experimental dogs were randomly divided into control, pyridoxine, and pyridoxine + β-NGF groups. We observed chronological changes of morphology in the dorsal root ganglia in response to pyridoxine toxicity based on cresyl violet staining. The number of large neurons positive for cresyl violet was dramatically decreased after pyridoxine intoxication for 7 days in the dorsal root ganglia and the neuron number was gradually increased after pyridoxine withdrawal. In addition, we also investigated the effects of β-NGF gene therapy on neuronal plasticity in pyridoxine-induced neuropathic dogs. To accomplish this, tyrosine kinase receptor A(TrkA), βIII-tubulin and doublecortin(DCX) immunohistochemical staining was performed at 3 days after the last pyridoxine treatment. TrkA-immunoreactive neurons were dramatically decreased in the pyridoxine group compared to the control group, but strong TrkA immunoreactivity was observed in the small-sized dorsal root ganglia in this group. TrkA immunoreactivity in the dorsal root ganglia was similar between β-NGF and control groups. The numbers of βIII-tubulin-and DCX-immunoreactive cells decreased significantly in the pyridoxine group compared to the control group. However, the reduction of βIII-tubulin-and DCX-immunoreactive cells in the dorsal root ganglia in the β-NGF group was significantly ameliorated than that in the pyridoxine group. These results indicate that β-NGF gene therapy is a powerful treatment of pyridoxine-induced neuropathic damage by increasing the TrkA and DCX levels in the dorsal root ganglia. The experimental protocol was approved by the Institutional Animal Care and Use Committee(IACUC) of Seoul National University, South Korea(approval No. SNU-060623-1, SNU-091009-1) on June 23, 2006 and October 9, 2009, respectively.

关键词： β-nerve growth factor βIII-tubulin doublecortin gene therapy neuron-glial antigen 2 neuropathy pyridoxine

Preliminary experimental study of a supercritical CO2 power cycle test loop with a high-speed turbo-generator using R134a under similarity conditions

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Frontiers in Energy 2017年第4期11卷 452-460页

作者： Junhyun cho Hyungki SHIN Jongjae cho young-Seok KANG Ho-Sang RA Chulwoo ROH Beomjoon LEE Gilbong LEE Byunghui KIM young-jin BAIK Thermal Energy System Laboratory Korea Institute of Energy Research 152 Gajeong-ro Yusung-gu Daejeon 34129 Republic of Korea Engine Component Research Team Korea Aerospace Research Institute (KARl) 169-84 Gwahak-ro Yusung-gu Daejeon 34133 Republic of Korea InGineers 21 Saman-ro 16 Beon-gil Gimhae-si Gyeongsangnam-do 621-220 Republic of Korea

Research on applying a supercritical carbon dioxide power cycle （S-CO2） to concentrating solar power （CSP） instead of a steam Rankine cycle or an air Brayton cycle has been recently conducted. An S-CO2 system is suitable for CSP owing to its compactness, higher efficiency, and dry-cooling capability. At the Korea Institute of Energy Research （KIER）, to implement an S-CO2 system, a 10 kWe class test loop with a turbine- alternator-compressor （TAC） using gas foil bearings was developed. A basic sub-kWe class test loop with a high- speed radial type turbo-generator and a test loop with a capability of tens of kWe with an axial type turbo- generator were then developed. To solve the technical bottleneck of S-CO2 turbomachinery, a partial admission nozzle and oil-lubrication bearings were used in the turbo- generators. To experience the closed-power cycle and develop an operational strategy of S-CO2 operated at high pressure, an organic Rankine cycle （ORC） operating test using a refrigerant as the working fluid was conducted owing to its operational capability at relatively low- pressure conditions of approximately 30 to 40 bar. By operating the sub-kWe class test loop using R134a as the working fluid instead of CO2, an average turbine power of 400 W was obtained.

关键词： supercritical CO2 power cycle turbomachin-ery compressor turbine

Monolayer Graphitic Carbon Nitride as Metal-Free Catalyst with Enhanced Performance in Photo- and Electro-Catalysis

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Nano-Micro Letters 2022年第3期14卷 308-321页

作者： Huiyan Piao Goeun choi Xiaoyan jin Seong‑Ju Hwang young Jae Song Sung‑Pyo cho jin‑Ho choy Intelligent Nanohybrid Materials Laboratory(INML) Institute of Tissue Regeneration Engineering(ITREN)Dankook UniversityCheonan 31116Republic of Korea College of Science and Technology Dankook UniversityCheonan 31116Republic of Korea Department of Nanobiomedical Science and BK21 PLUS NBM Global Research Center for Regenerative Medicine Dankook UniversityCheonan 31116Republic of Korea Department of Materials Science and Engineering College of EngineeringYonsei UniversitySeoul 03722Republic of Korea SKKU Advanced Institute of Nanotechnology(SAINT) Sungkyunkwan University(SKKU)Suwon 440‑746Republic of Korea Department of Nano Engineering Sungkyunkwan University(SKKU)Suwon 440‑746Republic of Korea National Center for Inter‑University Research Facilities(NCIRF) Seoul National UniversitySeoul 08826Republic of Korea Graphene Research Center Advanced Institute of Convergence TechnologySuwon 16229Republic of Korea Department of Pre‑Medical Course College of MedicineDankook UniversityCheonan 31116Republic of Korea Tokyo Tech World Research Hub Initiative(WRHI) Institute of Innovative ResearchTokyo Institute of TechnologyYokohama 226‑8503Japan

The exfoliation of bulk graphitic carbon nitride(g-C_(3)N_(4))into monolayer has been intensively studied to induce maximum sur-face area for fundamental studies,but ended in failure to realize chemi-cally and physically well-defined monolayer of g-C_(3)N_(4)mostly due to the difficulty in reducing the layer thickness down to an atomic *** has,therefore,remained as a challenging issue in two-dimensional(2D)chemistry and physics *** this study,an“atomic monolayer of g-C_(3)N_(4)with perfect two-dimensional limit”was successfully prepared by the chemically well-defined two-step *** atomically resolved monolayer of g-C_(3)N_(4)was also confirmed by spectroscopic and micro-scopic *** addition,the experimental Cs-HRTEM image was collected,for the first time,which was in excellent agreement with the theoretically simulated;the evidence of monolayer of g-C_(3)N_(4)in the perfect 2D limit becomes now clear from the HRTEM image of orderly hexagonal symmetry with a cavity formed by encirclement of three adjacent heptazine *** to bulk g-C_(3)N_(4),the present g-C_(3)N_(4)monolayer showed significantly higher photocatalytic gen-eration of H2O2 and H2,and electrocatalytic oxygen reduction *** addition,its photocatalytic efficiency for H2O2 production was found to be the best for any known g-C_(3)N_(4)nanomaterials,underscoring the remarkable advantage of monolayer formation in optimizing the catalyst performance of g-C_(3)N_(4).

关键词： Graphitic carbon nitride Monolayer Atomic image Electro-and photo-catalysis

High-index-contrast photonic structures:a versatile platform for photon manipulation

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Light(Science & Applications) 2022年第11期11卷 2617-2632页

作者： young-Bin Kim jin-Woo cho Yun-Jo Lee Dukkyu Bae Sun-Kyung Kim Department of Applied Physics Kyung Hee UniversityYonginGyeonggido 17104Republic of Korea Hexa Solution Co. LtdSuwonGyeonggi-do 16229Republic of Korea

In optics,the refractive index of a material and its spatial distribution determine the characteristics of light ***,exploring both low-and high-index materials/structures is an important consideration in this *** cavities,which are defined as low-index bases,exhibit a variety of unusual or even unexplored optical characteristics and are used in numerous functionalities including diffraction gratings,localised optical antennas and low-loss *** this report,we discuss the fabrication of hollow cavities of various sizes(O.2-5μm in diameter)that are supported by conformal dielectric/metal shells,as well as their specific applications in the ultraviolet(photodetectors),visible(light-emitting diodes,solar cells and metalenses),near-infrared(thermophotovoltaics)and mid-infrared(radiative coolers)*** findings demonstrate that hollow cavities tailored to specific spectra and applications can serve as versatile optical platforms to address the limitations of current optoelectronic ***,hollow cavity embedded structures are highly elastic and can minimise the thermal stress caused by high *** such,future applications will likely include high-temperature devices such as thermophotovoltaics and concentrator photovoltaics.

关键词： versatile index ultraviolet

Effect of Co-Deposited Iron on Microstructures and Properties of Electroplated Nanocrystalline Nickel-Iron Alloys

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Journal of Rare Earths 2006年第z1期24卷 94-99页

作者： Myung Hwan Byun jin Woo cho Beom Suck Han young Keun Kim Yo Seung Song Department of Materials Engineering Hankuk Aviation University 200-1 Goyang Korea Nano Technology Based Information & Energy Storage Research Center Korea Electronics Technology Institute Bundang-gu Seongnam-Si 463-816 Korea Department of Materials Science and Engineering Korea University Seoul 136-713 Korea Materials and Processing Research Team Korea Automobile Technology Institute Chonan Chungnam 330-912 Korea Department of Materials Science and Engineering Korea University Seoul 136-713 Korea Department of Materials Engineering Hankuk Aviation University 200-1 Goyang Korea

Nickel-iron nanocrystalline alloys with different compositions and grain sizes were fabricated by electroplating for MEMS devices. The iron content of the deposits was changed by varying the nickel/iron ion ratio in the electrolyte. X-ray diffraction (XRD) analysis was applied for measuring the strength of the texture and grain size of the deposits. The nickel/iron atom ratio of the deposits was analyzed by EDS. The hardness of the alloys was evaluated by Vickers hardness indenter. The internal stress of the deposits was measured by thin film stress measurement using Stoney's formula. Surface morphology and roughness were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Hardness and internal stress mechanism of the electroplated structure as a function of Fe ion content and current density were revealed. With increasing the iron content, the hardness and internal stress of the deposits increase. An excellent correlation between the increase in the internal stress and the loss of (200) texture were found.

关键词： MEMS electroplating nanocrystalline nickel-iron alloy grain size internal stress hardness roughness