39 results on '"Hyang Yeon, Kim"'
Search Results
2. Analytical method development and dermal absorption of 2-amino-5-nitrophenol (2A5NP), a hair dye ingredient under oxidative condition
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Yu Jin Kim, Hyang Yeon Kim, Jung Dae Lee, Hong Yoon Kim, Jueng Eun Im, and Kyu-Bong Kim
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Health, Toxicology and Mutagenesis ,Toxicology - Published
- 2022
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3. Lithium Battery Performances of Porous Si-Ni-Fe Ternary Alloy Anode
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Hyoung-Kyu Kang, Sang-Hyoung Kim, Umirov Nurzhan, Hyang-Yeon Kim, and Sung-Soo Kim
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- 2021
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4. Metabolomics profiling of valproic acid-induced symptoms resembling autism spectrum disorders using 1H NMR spectral analysis in rat model
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Suhkmann Kim, Hyang Yeon Kim, Kyu-Bong Kim, Ji-Woon Kim, Yong Jae Lee, Mee Jung Ko, Jung Dae Lee, Chan Young Shin, and Sun Jae Kim
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Male ,medicine.medical_specialty ,Taurine ,Autism Spectrum Disorder ,Offspring ,Proton Magnetic Resonance Spectroscopy ,Health, Toxicology and Mutagenesis ,Urinary system ,Central nervous system ,Toxicology ,Creatine ,chemistry.chemical_compound ,Metabolomics ,Internal medicine ,medicine ,Animals ,Valproic Acid ,business.industry ,Brain ,Rats ,Glutamine ,Disease Models, Animal ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Maternal Exposure ,Female ,lipids (amino acids, peptides, and proteins) ,business ,Biomarkers ,medicine.drug - Abstract
Prenatal exposure to valproic acid (VPA) has been implicated in the manifestation of autism spectrum disorder (ASD)-like behavioral and functional changes both in human and rodents including mice and rats. The objective of this study was to determine metabolomics profiling and biomarkers related to VPA-induced symptoms resembling ASD using proton nuclear magnetic resonance (1H-NMR) spectral data. VPA was administered to pregnant rats at gestation day 12.5 and effects measured subsequently in male 4-week-old offspring pups. The sociability of VPA-treated animals was significantly diminished and exhibited ASD-like behavior as evidenced by reduction of social adaptation disorder and lack of social interactions. To find biomarkers related to ASD, the following were collected prefrontal brain cortices, urine bladder and blood samples directly from heart puncture. In all samples, principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) displayed significant clustering pattern differences between control and treated groups. Valine, taurine, myo-inositol, 3-hydroxybutyrate and 1,3-dihydroxyacetone were significantly decreased in brain cortices in treated rats. Serum metabolites of glucose, creatine phosphate, lactate, glutamine and threonine were significantly increased in VPA-administered animals. Urinary metabolites of pimelate, 3-hydroxyisovalerate and valerate were significantly reduced in VPA-treated rat, whereas galactose and galactonate levels were elevated. Various metabolites were associated with mitochondrial dysfunction metabolism and central nervous system disorders. Data demonstrated that VPA-induced alterations in endogenous metabolites of serum, urine, and brain cortex which might prove useful as biomarkers for symptoms resembling ASD as a model of this disorder.
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- 2021
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5. Effects of anti-wrinkle and skin-whitening fermented black ginseng on human subjects and underlying mechanism of action
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Jueng Eun Im, Hyang Yeon Kim, Jin Ju Park, Eun Young Lee, Dong-Wan Seo, Kyu-Bong Kim, Junmin An, Jaehyoun Ha, Jung Dae Lee, and Chang Hui Cho
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0301 basic medicine ,Cell Survival ,media_common.quotation_subject ,Health, Toxicology and Mutagenesis ,Skin Cream ,Panax ,Skin Pigmentation ,Matrix Metalloproteinase Inhibitors ,Toxicology ,Cosmetics ,Cell Line ,Mice ,Ginseng ,03 medical and health sciences ,0302 clinical medicine ,Animals ,Humans ,Medicine ,media_common ,Melanins ,Traditional medicine ,Monophenol Monooxygenase ,Plant Extracts ,business.industry ,food and beverages ,Skin whitening ,Dihydroxyphenylalanine ,Skin Aging ,carbohydrates (lipids) ,030104 developmental biology ,Mechanism of action ,Anti wrinkle ,030220 oncology & carcinogenesis ,Fermentation ,Collagen ,medicine.symptom ,business ,Oxidation-Reduction - Abstract
The aim of this study was to determine the effects of anti-wrinkle and skin-whitening of fermented black ginseng (FBG) in human subjects and to examine underlying biochemical mechanisms of action. A clinical study was performed to evaluate efficacy and safety using a 1% FBG cream formulation. Twenty-three subjects were recruited and instructed to apply control or FBG creams each on half of their face twice daily for 8 weeks. After 8 weeks, FBG cream significantly reduced the appearance of eye wrinkles compared to prior to exposure and control cream. Skin color was significantly brightened using FBG cream in comparison with a control cream. To determine the mechanism of actions involved in anti-wrinkle and skin-whitening effects various concentrations of FBG were applied to human fibroblast CCD-986sk and mouse melanoma B16F1 cells. Collagen synthesis in CCD-986sk cells was improved significantly at 1, 3, 10, or 30 µg/ml of FBG. At 30 µg/ml, FBG significantly inhibited (73%) collagenase, and matrix metalloproteinase-1 (MMP-1) compared to control. Tyrosinase activity and DOPA (3,4-dihydroxy-L-phenylalanine) oxidation were significantly decreased at all tested concentrations. Melanin production in B16F1 cells was concentration-dependently reduced from 15% to 60% by all concentrations of FBG. These results suggested that a 1% FBG cream exerted anti-wrinkle and skin-whitening effects.
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- 2020
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6. Pharmacokinetics and the Dermal Absorption of Bromochlorophene, a Cosmetic Preservative Ingredient, in Rats
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Yong-Jae Lee, Hyang-Yeon Kim, Quynh-Lien Pham, Jung-Dae Lee, and Kyu-Bong Kim
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Chemical Health and Safety ,integumentary system ,Health, Toxicology and Mutagenesis ,bromochlorophene ,in vitro dermal absorption ,in vivo pharmacokinetics ,Toxicology - Abstract
The cosmetic industry has flourished in recent years. Accordingly, the safety of cosmetic ingredients is increasing. Bromochlorophene (BCP) is a commonly used cosmetic preservative. To evaluate the effects of BCP exposure, in vitro dermal absorption and in vivo pharmacokinetic (PK) studies were conducted using gel and cream formulations. The Franz diffusion cell system and rat dorsal skin were used for tests according to the Korea Ministry of Food and Drug Safety guidelines for in vitro skin absorption methods. After the dermal application (1.13 mg/cm2) of BCP in the gel and cream formulations, liquid chromatography–mass spectrometry (LC–MS/MS) was used to evaluate the amount of BCP that remained unabsorbed on the skin (WASH), and that was present in the receptor fluid (RF), stratum corneum (SC), and (epi)dermis (SKIN). The total dermal absorption rate of BCP was 7.42 ± 0.74% for the gel formulation and 1.5 ± 0.9% for the cream formulation. Total recovery in an in vitro dermal absorption study was 109.12 ± 8.79% and 105.43 ± 11.07% for the gel and cream formulations, respectively. In vivo PK and dermal absorption studies of BCP were performed following the Organization for Economic Cooperation and Development guidelines 417 and 427, respectively. When intravenous (i.v.) pharmacokinetics was performed, BCP was dissolved in glycerol formal and injected into the tail vein (n = 3) of the rats at doses of 1 and 0.2 mg/kg. Dermal PK parameters were estimated by the application of the gel and cream formulations (2.34 mg/kg of BCP as an active ingredient) to the dorsal skin of the rats. Intravenous and dermal PK parameters were analyzed using a non-compartmental method. The dermal bioavailability of BCP was determined as 12.20 ± 2.63% and 4.65 ± 0.60% for the gel and cream formulations, respectively. The representative dermal absorption of BCP was evaluated to be 12.20 ± 2.63% based on the results of the in vivo PK study.
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- 2022
7. Crystallization Effect of Ti4ni4si7 Phase in Nano-Sized Silicon Embedded Silicide Alloy Matrix as Anode for Sulfide Based All-Solid-State Battery
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Hyoung-Kyu Kang, Yun-Chae Jung, Sang-Hyoung Kim, Hyang-Yeon Kim, Ji-Sang Yu, and Sung-Soo Kim
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- 2022
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8. Urinary Metabolomics in Young Soccer Players after Winter Training Season
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Hyang-Yeon Kim, Jung-Dae Lee, Yun-Hwan Lee, Sang-Won Seo, Ho-Seong Lee, Suhkmann Kim, and Kyu-Bong Kim
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winter training season ,young soccer players ,NMR analysis ,multivariate analysis ,recovery ,Endocrinology, Diabetes and Metabolism ,Molecular Biology ,Biochemistry - Abstract
During the off-season, soccer players in Korea attend the winter training season (WTS) to build running stamina for the next season. For young soccer players, proper recovery time is needed to prevent injury or muscle damage. In this study, urinary metabolites in young players after 1, 5, and 10 days of the WTS were analyzed using nuclear magnetic resonance spectroscopy (NMR) combined with multivariate analysis to suggest appropriate recovery times for improving their soccer skills. After NMR analysis of the urine samples obtained from young players, 79 metabolites were identified, and each group (1, 5, or 10 days after WTS) was separated from the before the WTS group in the target profiling analysis using partial least squares-discriminant analysis (PLS-DA). Of these, 15 metabolites, including 1-methylnicotinamide, 3-indoxylsulfate, galactarate, glutamate, glycerol, histamine, methylmalonate, maltose, N-phenylacetylglycine, trimethylamine, urea, 2-hydroxybutyrate, adenine, alanine, and lactate, were significantly different than those from before the WTS and were mainly involved in the urea, purine nucleotide, and glucose-alanine cycles. In this study, most selected metabolites increased 1 day after the WTS and then returned to normal levels. However, 4 metabolites, adenine, 2-hydroxybutyrate, alanine, and lactate, increased during the 5 days of recovery time following the WTS. Based on excess ammonia, adenine, and lactate levels in the urine, at least 5 days of recovery time can be considered appropriate.
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- 2022
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9. Pragmatic Approach to Design Silicon Alloy Anode by the Equilibrium Method
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Hyang-Yeon Kim, Nurzhan Umirov, Deok-Ho Seo, and Sung-Soo Kim
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Materials science ,Silicon ,020209 energy ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Anode ,Silicon alloy ,chemistry ,Amorphous matrix ,0202 electrical engineering, electronic engineering, information engineering ,Energy density ,General Materials Science ,Graphite ,Melt spinning ,Composite material ,0210 nano-technology ,Nano silicon - Abstract
Silicon fascinates with incredibly high theoretical energy density as an anode material and considered as a primary candidate to replace well-established graphite. However, further commercialization is hindered by the abnormal volume changes of Si in every single cycle. Silicon embedded in a buffer matrix using the melt-spinning process is a promising approach; however, its metastable nature significantly reduces the microstructure homogeneity, the quality of the composition, and, therefore, the electrochemical performances. Herein, we developed a new approach to design a high-performance Si-alloy with improved microstructure uniformity and electrochemical properties. Namely, annealing at a certain temperature of the melt-spun amorphous alloy ribbon allowed us to evenly distribute Si nanocrystallites in the microstructure with control of average grain size. As a result, the Si-alloy electrode delivers an initial discharge capacity of 900 mAh g
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- 2020
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10. Genome‐scale metabolic reconstruction and in silico analysis of the rice leaf blight pathogen,Xanthomonas oryzae
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Hyang Yeon Kim, Lokanand Koduru, Dong-Yup Lee, Meiyappan Lakshmanan, Bijayalaxmi Mohanty, Choong Hwan Lee, and Yi Qing Lee
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0106 biological sciences ,0301 basic medicine ,rice leaf blight pathogen ,Xanthomonas ,In silico ,Soil Science ,Virulence ,Plant Science ,Xanthomonas oryzae ,01 natural sciences ,03 medical and health sciences ,diffusible signal factor ,Bacterial Proteins ,Blight ,Molecular Biology ,Pathogen ,Gene ,Plant Diseases ,Genetics ,nitrogenous fertilizers ,biology ,Systems Biology ,food and beverages ,Oryza ,Original Articles ,genome‐scale metabolic model ,biology.organism_classification ,030104 developmental biology ,Regulon ,Original Article ,antibacterial targets ,Agronomy and Crop Science ,Bacteria ,010606 plant biology & botany - Abstract
Xanthomonas oryzae pv. oryzae (Xoo) is a vascular pathogen that causes leaf blight in rice, leading to severe yield losses. Since the usage of chemical control methods has not been very promising for the future disease management, it is of high importance to systematically gain new insights about Xoo virulence and pathogenesis, and devise effective strategies to combat the rice disease. To do this, we reconstructed a genome‐scale metabolic model of Xoo (iXOO673) and validated the model predictions using culture experiments. Comparison of the metabolic architecture of Xoo and other plant pathogens indicated that the Entner–Doudoroff pathway is a more common feature in these bacteria than previously thought, while suggesting some of the unique virulence mechanisms related to Xoo metabolism. Subsequent constraint‐based flux analysis allowed us to show that Xoo modulates fluxes through gluconeogenesis, glycogen biosynthesis, and degradation pathways, thereby exacerbating the leaf blight in rice exposed to nitrogenous fertilizers, which is remarkably consistent with published experimental literature. Moreover, model‐based interrogation of transcriptomic data revealed the metabolic components under the diffusible signal factor regulon that are crucial for virulence and survival in Xoo. Finally, we identified promising antibacterial targets for the control of leaf blight in rice by using gene essentiality analysis., We reconstructed a genome‐scale metabolic model of the rice leaf pathogen Xanthomonas oryzae for understanding its virulence and survival, and identified promising antibacterial targets.
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- 2020
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11. A Study on Critical Literacy Education Using Novel in General Education -Focusing on Kim Ae-ran’s 'Goliath under water'-
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Hyang-Yeon Kim
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Critical literacy ,Pedagogy ,Ran ,General education ,General Medicine ,Sociology - Published
- 2020
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12. Risk assessment of volatile organic compounds (VOCs) detected in sanitary pads
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Eunji Baek, Kyungwon Seo, Jung Dae Lee, Chungsik Min, Byung-Mu Lee, Hyang Yeon Kim, Joo Young Lee, Kyu-Bong Kim, Yong-Kyu Choi, Ok-Nam Bae, Ki Hwan Choi, Ji-Young Kim, and Sejin Kang
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Sanitary pads ,Health, Toxicology and Mutagenesis ,010501 environmental sciences ,Toxicology ,Body weight ,Risk Assessment ,01 natural sciences ,World health ,03 medical and health sciences ,Risk Factors ,Humans ,Medicine ,Health risk ,030304 developmental biology ,0105 earth and related environmental sciences ,Air Pollutants ,Volatile Organic Compounds ,0303 health sciences ,Reference dose ,business.industry ,Environmental Exposure ,Margin of exposure ,Consumer Product Safety ,Women's Health ,Cancer risk ,business ,Risk assessment ,Environmental Monitoring - Abstract
Disposable sanitary pads are a necessity for women's health, but safety concerns regarding the use of these products have created anxiety. The aim of this study was to conduct a risk assessment of 74 volatile organic compounds (VOCs), which were expected to be contained within sanitary pads. Of the 74 VOCs, 50 were found in sanitary pads retailed in Korea at concentrations ranging from 0.025 to 3548.09 µg/pad. In order to undertake a risk assessment of the VOCs, the toxicological database of these compounds in the United States Environmental Protection Agency (USEPA), Agency for Toxic Substances and Disease Registry (ATSDR), National Toxicology Program (NTP) and World Health Organization (WHO) was searched. Ethanol was found to exhibit the highest reference dose (RfD) while 1,2-dibromo-3-chloro-propane displayed the lowest RfD. Consequently, a worst-case exposure scenario was applied in this study. It was assumed that there was the use of 7.5 sanitary napkins/day for 7 days/month. In the case of panty liners or overnight sanitary napkins, the utilization of 90 panty liners/month or 21 overnight sanitary napkins/month was assumed, respectively. In addition, 43 kg, the body weight of 12 to 13-year-old young women, and 100% VOCs skin absorption were employed for risk assessment. The systemic exposure dose (SED) values were calculated ranging from 1.74 (1,1,2-trichloroethane) ng/kg/day to 144.4 (ethanol, absolute) µg/kg/day. Uncertainty factors (UFs) were applied ranging from 10 to 100,000 in accordance with the robustness of animal or human experiments. The margin of exposure (MOE) of 34 VOCs was more than 1 (acceptable MOE > 1). Applicable carcinogenic references reported that the cancer risk of five VOCs was below 10-6. Based on our findings, evidence indicates that the non-cancer and cancer risks associated with VOCs detected in sanitary pads currently used in South Korea do not pose an adverse health risk in women.
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- 2019
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13. Microstructure and electrochemical properties of rapidly solidified Si–Ni alloys as anode for lithium-ion batteries
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Hyang-Yeon Kim, Taekeun Kim, Deok-Ho Seo, Sung-Soo Kim, and Nurzhan Umirov
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Materials science ,Chemical substance ,Open-circuit voltage ,General Chemical Engineering ,Alloy ,chemistry.chemical_element ,02 engineering and technology ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,Microstructure ,01 natural sciences ,0104 chemical sciences ,Anode ,chemistry ,Chemical engineering ,Electrode ,engineering ,Lithium ,0210 nano-technology - Abstract
This paper reports an electrochemically highly reversible Si–Ni alloy based electrode through the microstructure and composition analysis using XRD and HR-TEM combined with EDS. Nano-Si (∼200 nm) embedded in the inactive NiSi2/NiSi matrix synthesized using industrial-scale rapid solidification process (RSP). In addition, comprehensive analysis of HR-TEM images, dQ/dV and OCV plots provides powerful insights into the cycle life degradation of Si-alloys caused by the material state change upon cycling.
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- 2019
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14. Effect of Application Amounts on In Vitro Dermal Absorption Test Using Caffeine and Testosterone
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Jin-Ju Park, Jueng-Eun Im, Hyang Yeon Kim, Kyu-Bong Kim, Jung Dae Lee, and Kyung-Soo Kang
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Pharmaceutical Science ,010501 environmental sciences ,01 natural sciences ,High-performance liquid chromatography ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Pharmacy and materia medica ,Dermis ,Stratum corneum ,medicine ,Testosterone ,030304 developmental biology ,0105 earth and related environmental sciences ,caffeine ,0303 health sciences ,Chromatography ,Epidermis (botany) ,integumentary system ,application amounts ,in vitro ,dermal absorption ,In vitro ,RS1-441 ,medicine.anatomical_structure ,chemistry ,testosterone ,Application dose ,Caffeine - Abstract
Dermal absorption of chemicals is a key factor in risk assessment. This study investigated the effects of different amounts of application on dermal absorption and suggested an appropriate application dose for proper dermal absorption. Caffeine and testosterone were chosen as test compounds. An in vitro dermal absorption test was performed using a Franz diffusion cell. Different amounts (5, 10, 25, and 50 mg (or µL)/cm2) of semisolid (cream) and liquid (solution) formulations containing 1% caffeine and 0.1% testosterone were applied to rat and minipig (Micropig®) skins. After 24 h, the concentrations of both compounds remaining on the skin surface and in the stratum corneum, dermis and epidermis, and receptor fluid were determined using LC-MS / MS or HPLC. Dermal absorption of both compounds decreased with increasing amounts of application in both skin types (rat and minipig) and formulations (cream and solution). Especially, dermal absorptions (%) of both compounds at 50 mg (or µL)/cm2 was significantly lower compared to 5 or 10 mg (or µL)/cm2 in both rat and minipig skins. Therefore, a low dose (5 or 10 mg (or µL)/cm2) of the formulation should be applied to obtain conservative dermal absorption.
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- 2021
15. Relationship between Mechanical and Electrochemical Property in Silicon Alloy Designed by Grain Size as Anode for Lithium-Ion Batteries
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Sang-Gu Ji, Nurzhan Umirov, Hyang-Yeon Kim, and Sung-Soo Kim
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Renewable Energy, Sustainability and the Environment ,Materials Chemistry ,Electrochemistry ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Abstract
While silicon has a very high theoretical capacity but has relatively the stresses produced by volume changes during charge/discharge cycling lead to structural modifications (around 300%). To overcome this problem, many studies are being conducted to commercialize silicon. Herein, we produced amorphous silicon alloy using a melt-spinning method. Then, through annealing under various temperatures, we gradually recrystallized the silicon phase. Average silicon grain sizes were 70 and 130 nm for silicon alloys annealed at 800 and 873 K, respectively. The initial reversible capacities of silicon alloy-based anodes were 844.3 (800 K) and 865.1 mAh g−1 (873 K), and, after 100 cycles, capacity retention rates were found to be 68.5 (800 K) and 40.5% (873 K). At this stage, to elucidate the effect of grain sizes on cycle life retention rate, we determined mechanical hardness through nanoindentation. And, by measuring volume expansion values between cycles through in situ dilation, we could identify the relationship between electrochemical property and mechanical hardness of silicon alloy samples depending on recrystallized grain sizes. Thus, by analyzing the mechanical and electrochemical properties of silicon alloys depending on silicon grain sizes, we want to highlight the importance of controlling silicon grain size.
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- 2022
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16. Metabolomics approach to biomarkers of dry eye disease using
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Jung Dae, Lee, Hyang Yeon, Kim, Jin Ju, Park, Soo Bean, Oh, Hyeyoon, Goo, Kyong Jin, Cho, Suhkmann, Kim, and Kyu-Bong, Kim
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Cornea ,Male ,Rats, Sprague-Dawley ,Proton Magnetic Resonance Spectroscopy ,Tears ,Animals ,Metabolomics ,Dry Eye Syndromes ,Biomarkers ,Rats - Abstract
Dry eye disease (DED) is a chronic and progressive lesion on the ocular surface and induces symptoms, such as burning sensation, itchy eyes, heavy eyes, tired eyes, dry feeling, facial flushing, and blurred vision. The present study was performed to develop DED biomarkers using metabolomics in a rat model. DED was induced by injecting scopolamine and exposing rats to a dry condition. Scopolamine (12 mg/kg/day for 7 days) was subcutaneously injected to male Sprague-Dawley rats. The rats were placed in dry condition with air-flow and dehumidifier. Tear volume and tear breakup time (TBUT) were measured, and eyes were examined through fluorescein staining to assess DED. Mucosal damage and immune reactions were also determined. Plasma and urinary endogenous metabolites were determined using
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- 2021
17. Metabolomics approach to biomarkers of dry eye disease using 1H-NMR in rats
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Kyong Jin Cho, Soo Bean Oh, Jung Dae Lee, Hyeyoon Goo, Kyu-Bong Kim, Suhkmann Kim, Hyang Yeon Kim, and Jin Ju Park
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0301 basic medicine ,Facial flushing ,medicine.medical_specialty ,Itchy eyes ,genetic structures ,business.industry ,Health, Toxicology and Mutagenesis ,Rat model ,Disease ,Toxicology ,eye diseases ,Lesion ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Ophthalmology ,Medicine ,Biomarker (medicine) ,sense organs ,medicine.symptom ,business ,Ocular surface ,Burning Sensation - Abstract
Dry eye disease (DED) is a chronic and progressive lesion on the ocular surface and induces symptoms, such as burning sensation, itchy eyes, heavy eyes, tired eyes, dry feeling, facial flushing, and blurred vision. The present study was performed to develop DED biomarkers using metabolomics in a rat model. DED was induced by injecting scopolamine and exposing rats to a dry condition. Scopolamine (12 mg/kg/day for 7 days) was subcutaneously injected to male Sprague–Dawley rats. The rats were placed in dry condition with air-flow and dehumidifier. Tear volume and tear breakup time (TBUT) were measured, and eyes were examined through fluorescein staining to assess DED. Mucosal damage and immune reactions were also determined. Plasma and urinary endogenous metabolites were determined using 1H-NMR analysis. Compared with control tear and TBUT levels were significantly decreased in the DED group whereas corneal damage was significantly increased. The levels of interleukins (IL-6) and IL-1β significantly elevated in the cornea and lacrimal glands in the DED group. TNF-α was numerically increased but not significantly different between groups. Pattern recognition using principal component analysis (PCA) and orthogonal projections to latent structure-discriminant analysis (OPLS-DA) of the NMR spectra in global profiling revealed different clusters between DED and control groups. Target profiling demonstrated that PCA and OPLS-DA score plots were separated between DED and controls in plasma and urine. Subsequently, 9 plasma metabolites were selected to examine different clustering between groups, and 26 urinary metabolites were also selected. Plasma metabolites showed a non-significant rising tendency in the DED group. Urinary phenylalanine, phenylacetate, pantothenate, glycine, succinate, methanol, valine, propylene glycol, histidine, threonine, lactate, and acetate were significantly different between control and DED rats. These results may contribute to understanding the metabolic regulation that is involved in DED and might be useful for potential biomarkers related to DED in rats.
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- 2021
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18. Analytical method development of methylisothiazolinone, a preservative, in rat plasma using LC-MS/MS
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Kyu-Bong Kim, Hyang Yeon Kim, and Yong Jae Lee
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Male ,Preservative ,Calibration curve ,Metabolite ,Clinical Biochemistry ,01 natural sciences ,Biochemistry ,Analytical Chemistry ,030207 dermatology & venereal diseases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Drug Stability ,Pharmacokinetics ,Limit of Detection ,Tandem Mass Spectrometry ,Methylisothiazolinone ,Animals ,Chromatography ,010401 analytical chemistry ,Selected reaction monitoring ,Area under the curve ,Reproducibility of Results ,Cell Biology ,General Medicine ,Rats ,0104 chemical sciences ,Thiazoles ,chemistry ,Toxicity ,Linear Models ,Chromatography, Liquid - Abstract
Methylisothiazolinone (MI) is a preservative used in consumer products to control bacterial and fungal growth. MI can be toxic, act as a skin sensitizer and irritant, and initiate lung diseases; therefore, it is important to understand the mechanisms underlying the toxicity of MI in the body. In this study, we developed a method to analyze plasma MI by using an LC-MS/MS-coupled multiple reaction monitoring (MRM) technique, which follows the fragments of a target metabolite in rat plasma. The MRM transition of MI was m/z 116 ➔ 101, and the lower limit of quantification (LLOQ) was set at 10 ng/mL. Including the concentration of LLOQ, a seven-point calibration curve explained much of the variation in the response, and it was strongly linear (R2 = 0.9998); its intra- and inter-day accuracy and precision values were within 15% of the standard deviation (SD%) and along with the FDA and Korea Ministry of Food and Drug Safety guidelines. For intravenous (iv) pharmacokinetic studies of MI using rats, we developed an analytical method that was useful in detecting the profile of MI in the plasma. We also determined half-life, and area under the curve (AUC) of MI using a non-compartment model, and these might be useful for the study of toxic mechanisms of MI in the body.
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- 2018
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19. Fundamental Approach to Capacity Prediction of Si-Alloys as Anode Material for Li-ion Batteries
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Jong Su Kim, Nurzhan Umirov, Hyang-Yeon Kim, and Sung-Soo Kim
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020209 energy ,0202 electrical engineering, electronic engineering, information engineering ,Electrochemistry ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences - Published
- 2018
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20. Measurements of Magnetic Properties of Melt-Spun Amorphous Ribbon by Single Strip Method
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Soo Young Park, Sung Woo Lee, Hyang Yeon Kim, Jae-Woong Lee, and Jong-Ryul Jeong
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Materials science ,Amorphous ribbon ,Composite material - Published
- 2017
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21. Novel silane-treated polyacrylonitrile as a promising negative electrode binder for LIBs
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Seongjun Moon, Nurzhan Umirov, Sung-Soo Kim, Kyung Jin Lee, Gyori Park, and Hyang Yeon Kim
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Materials science ,Silicon ,Mechanical Engineering ,Metals and Alloys ,Polyacrylonitrile ,chemistry.chemical_element ,02 engineering and technology ,Thermal treatment ,Current collector ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Silane ,0104 chemical sciences ,Anode ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Mechanics of Materials ,Electrode ,Materials Chemistry ,0210 nano-technology - Abstract
With the rapid increment of the electric vehicle market, silicon has attracted tremendous attention as a promising anode material for lithium-ion batteries (LIB) due to its tenfold higher gravimetrical energy density compared with a traditional graphite anode. To eliminate the well-known poor cycle life issue originated from the large volume expansion of the silicon-based electrode, the development of novel polymeric binder is essential. Herein, we synthesized a novel silane-treated polyacrylonitrile (Si-PAN) as an anode binder using facile azide-nitrile click reaction. Incorporation of silane to the cyclized-PAN structure enhances affinity between the electrode components and a current collector because it has organic and inorganic moiety simultaneously in polymeric backbone. This work implements a Si-alloy (Si70Ni20Cu10) based electrode with improved capacity retention through the optimization of silane amount and thermal treatment condition. Namely, the electrode composing Si-treated PAN-2.0 binder and Si-alloy, after being thermally treated at 450 °C shows stable discharge capacity of 760 mA h g−1 upon 50 cycles, resulting in 46% capacity retention improvement against pristine PAN binder (at 450 °C). New binder demonstrates a great potential to improve the electrochemical properties of next-generation electrode materials for energy storage systems.
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- 2020
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22. Si Nano-crystallites embedded in Cu-Al-Fe matrix as an anode for Li secondary batteries
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Hyang-Yeon Kim, Byeong-Chul Yu, Hun-Joon Sohn, Jae Wook Sung, Seon Kyong Kim, and Cheol Ho Park
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Quenching ,Reaction mechanism ,Materials science ,General Chemical Engineering ,Alloy ,Metallurgy ,Composite number ,engineering.material ,Anode ,Stress (mechanics) ,Chemical engineering ,Phase (matter) ,Electrochemistry ,engineering ,High-resolution transmission electron microscopy - Abstract
Si nanocrystallites embedded in Cu-Al-Fe matrix were developed using arc melting followed by a rapid quenching method which could produce a large scale at one time. Si nanocrystallites of approximately 100 nm were dispersed in matrix composed of Al 4 Cu 9 and AlFe phases. To identify the reaction mechanism, the ex situ XRD and HRTEM analyses were employed. Only Si reacted with Li forming a Li 15 Si 4 phase as the final product while the Al 4 Cu 9 and AlFe phases acted as inactive matrix during the first discharge. The Si/Cu-Al-Fe composite showed a good cycle performance with 836 mAh g −1 over 50 cycles. This indicated that inactive matrices not only endured the stress caused by volume expansion of Li-Si alloy but also provided a good electron path as a conductor.
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- 2014
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23. Garlic Sprouting Is Associated with Increased Antioxidant Activity and Concomitant Changes in the Metabolite Profile
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Alexandra Zakarova, Ji Yeon Seo, Jeong Hwan Kim, Jung-Hye Shin, Choong Hwan Lee, Jong-Sang Kim, Kye Man Cho, and Hyang Yeon Kim
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Antioxidant ,Oxygen radical absorbance capacity ,Plant Extracts ,medicine.medical_treatment ,Metabolite ,In vitro toxicology ,food and beverages ,General Chemistry ,Health benefits ,Antioxidant potential ,Allium sativum ,Antioxidants ,chemistry.chemical_compound ,chemistry ,Biochemistry ,cardiovascular system ,medicine ,Food science ,Garlic ,General Agricultural and Biological Sciences ,Sprouting - Abstract
Although garlic (Allium sativum) has been extensively studied for its health benefits, sprouted garlic has received little attention. We hypothesized that sprouting garlic would stimulate the production of various phytochemicals that improve health. Ethanolic extracts from garlic sprouted for different periods had variable antioxidant activities when assessed with in vitro assays, including the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity assay and the oxygen radical absorbance capacity assay. Extracts from garlic sprouted for 5 days had the highest antioxidant activity, whereas extracts from raw garlic had relatively low antioxidant activity. Furthermore, sprouting changed the metabolite profile of garlic: the metabolite profile of garlic sprouted for 5-6 days was distinct from the metabolite profile of garlic sprouted for 0-4 days, which is consistent with the finding that garlic sprouted for 5 days had the highest antioxidant activity. Therefore, sprouting may be a useful way to improve the antioxidant potential of garlic.
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- 2014
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24. Mass Spectrometry-Based Metabolite Profiling and Bacterial Diversity Characterization of Korean Traditional Meju During Fermentation
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Chi Kwang Song, Sarah Lee, Choong Hwan Lee, Maria John Muthaiya, Hyang Yeon Kim, Ji-Young Oh, Beom Seok Kim, hyung seok Ryu, Eun Jung Jeon, Su Yun Lee, and Jung Min Lee
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chemistry.chemical_classification ,Meju ,Bacteria ,biology ,Metabolite ,Soy Foods ,food and beverages ,Biodiversity ,General Medicine ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Gas Chromatography-Mass Spectrometry ,Lactic acid ,chemistry.chemical_compound ,Isoflavonoid ,Biochemistry ,chemistry ,Fermentation ,Metabolome ,Monosaccharide ,Lactic Acid ,Biotechnology - Abstract
The metabolite profile of meju during fermentation was analyzed using mass spectrometry techniques, including GC-MS and LC-MS, and the bacterial diversity was characterized. The relative proportions of bacterial strains indicated that lactic acid bacteria, such as Enterococcus faecium and Leuconostoc lactis, were the dominant species. In partial least-squares discriminate analysis (PLS-DA), the componential changes, which depended on fermentation, proceeded gradually in both the GC-MS and LC-MS data sets. During fermentation, lactic acid, amino acids, monosaccharides, sugar alcohols, and isoflavonoid aglycones (daidzein and genistein) increased, whereas citric acid, glucosides, and disaccharides decreased. MS-based metabolite profiling and bacterial diversity characterization of meju demonstrated the changes in metabolites according to the fermentation period and provided a better understanding of the correlation between metabolites and bacterial diversity.
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- 2012
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25. Metabolite Profiling and Bioactivity of Rice Koji Fermented by Aspergillus Strains
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Jung-Nam Choi, Kwang-Hyeon Liu, Soo-Hwan Yeo, Ji-Ho Choi, Choong Hwan Lee, Hyang Yeon Kim, Ji-Young Kim, Sait Byul Park, and Ah-Jin Kim
- Subjects
Aspergillus ,biology ,Aspergillus oryzae ,Metabolite ,Tyrosinase ,food and beverages ,Oryza ,General Medicine ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Gas Chromatography-Mass Spectrometry ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Metabolome ,Fermentation ,Gas chromatography–mass spectrometry ,Kojic acid ,Microbial inoculant ,Biotechnology - Abstract
In this study, the metabolite profiles of three Aspergillus strains during rice koji fermentation were compared. In the partial least squares discriminant analysis-based gas chromatography-mass spectrometry data sets, the metabolite patterns of A. oryzae (KCCM 60345) were clearly distinguished from A. kawachii (KCCM 60552) and only marginal differences were observed for A. oryzae (KCCM 60551) fermentation. In the 2 days fermentation samples, the overall metabolite levels of A. oryzae (KCCM 60345) were similar to the A. oryzae (KCCM 60551) levels and lower than the A. kawachii (KCCM 60552) levels. In addition, we identified discriminators that were mainly contributing tyrosinase inhibition (kojic acid) and antioxidant activities (pyranonigrin A) in A. oryzae (KCCM 60345) and A. kawachii (KCCM 60552) inoculated rice koji, respectively. In this study, we demonstrated that the optimal inoculant Aspergillus strains and fermentation time for functional rice koji could be determined through a metabolomics approach with bioactivity correlations.
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- 2012
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26. Comparison of14C-radioactivity in rice-paddy soil exposed to atmospheric and elevated CO2conditions after14C-carbaryl treatment
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Hyang-Yeon Kim, Han-Yong Kim, Seul-Ki Kim, In Seon Kim, and Seon-Hwa Kim
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Greenhouse soil ,food and beverages ,General Medicine ,Rice straw ,Pesticide ,complex mixtures ,Background level ,chemistry.chemical_compound ,chemistry ,Environmental chemistry ,Carbaryl ,Paddy field ,Environmental science ,Rice plant - Abstract
This study was performed to investigate if elevated affects the residue pattern of in the soil environment after -carbaryl treatment -carbaryl was applied on the rice plant-grown greenhouse soil exposed to atmospheric and elevated conditions. -radioactivity was measured in the rhizospheric soil and rice straw samples six months after -carbaryl application. Significantly high radioactivity was observed in the soil exposed to atmospheric as compared to that in the soil exposed to elevated C(h. Background level of radioactivity was observed in rice plant samples. These observations suggest the possibility that elevated may affect residual radioactivity of -carbaryl in the soil rather than that in the plant.
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- 2009
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27. Effect of composition on the crystallization and magnetic properties of Fe–Co–Si–B–Nb amorphous alloys
- Author
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Hyang-Yeon Kim
- Subjects
Amorphous metal ,Materials science ,Mechanical Engineering ,Alloy ,engineering.material ,Glass material ,law.invention ,Crystallization temperature ,Crystallography ,Mechanics of Materials ,law ,engineering ,Curie temperature ,General Materials Science ,Composition (visual arts) ,Crystallization ,Supercooling - Abstract
The crystallization behavior and magnetic properties of Fe62Co10Si15−xB18−yNb(x + y)−5amorphous alloys with x = 0–5 and y = 0–5 were examined. Primary crystallization temperature of Fe62Co10Si15−xB13Nbx and Fe62Co10Si10B18−yNbyalloys increased with the addition of Nb. The primary and secondary crystallization temperatures were well separated when the Nb content is above 4 at%. The alloys with 15–18 at% B showed a distinct supercooled region. The Nb addition decreased the Curie temperature as well as room temperature saturation magnetization. The glassy-type Fe62Co10Si10B18 alloy exhibited good soft magnetic properties as well as a supercooled liquid region of 39 K. The finding of the glassy-type Fe-based alloy without Nb element exhibiting high Bs above 1.4 T is promising for future use as a soft magnetic glass material.
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- 2007
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28. Metabolomics-Based Chemotaxonomic Classification of Streptomyces spp. and Its Correlation with Antibacterial Activity
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Jeong-Gu Kim, Joo-Won Suh, Sarah Lee, Choong Hwan Lee, Mee Youn Lee, and Hyang Yeon Kim
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Xanthomonas ,Oxytetracycline ,Microbial Sensitivity Tests ,Secondary metabolite ,Biology ,Applied Microbiology and Biotechnology ,Streptomyces ,Metabolomics ,Xanthomonas oryzae ,medicine ,Pathogen ,Plant Diseases ,food and beverages ,Oryza ,General Medicine ,biology.organism_classification ,Anti-Bacterial Agents ,Biochemistry ,Chemotaxonomy ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Metabolome ,Antibacterial activity ,Biotechnology ,medicine.drug ,Chromatography, Liquid - Abstract
Secondary metabolite-based chemotaxonomic classification of Streptomyces (8 species, 14 strains) was performed using ultraperformance liquid chromatography-quadrupole-time-offlight- mass spectrometry with multivariate statistical analysis. Most strains were generally well separated by grouping under each species. In particular, S. rimosus was discriminated from t he r emaining s ev en s pecies ( S. coelicolor, S. griseus, S. indigoferus, S. peucetius, S. rubrolavendulae, S. scabiei, and S. virginiae) in partial least squares discriminant analysis, and oxytetracycline and rimocidin were identified as S. rimosus-specific metabolites. S. rimosus also showed high antibacterial activity against Xanthomonas oryzae pv. oryzae , the pathogen responsible for rice bacterial blight. This study demonstrated that metabolite-based chemotaxonomic classification is an effective tool for distinguishing Streptomyces spp. and for determining their species-specific metabolites.
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- 2015
29. Electrode properties of rapidly solidified Mg67Ni23Pd10 amorphous alloy
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Yoshiaki Arata, Shin-ichi Yamaura, Akihisa Inoue, Hyang-Yeon Kim, and Hisamichi Kimura
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Electrode material ,Materials science ,Amorphous metal ,Mechanical Engineering ,Metallurgy ,Discharge current ,Metals and Alloys ,Discharge coefficient ,Amorphous solid ,Plateau pressure ,Mechanics of Materials ,Electrode ,Materials Chemistry ,Current density - Abstract
A Mg67Ni23Pd10 amorphous alloy was synthesized by rapid solidification and its electrode properties were examined. The discharge capacities increased with increasing cycle number and reached as high as 550 and 529 mAh/g at the discharge current densities of 10 and 20 mA/g, respectively. The plateau pressure of electrochemically derived P–C isotherm was about 10−5 MPa.
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- 2002
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30. Thermal stabilities and discharge capacities of melt-spun Mg–Ni-based amorphous alloys
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Akihisa Inoue, Shin-ichi Yamaura, Hisamichi Kimura, Yoshiaki Arata, and Hyang Yeon Kim
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Materials science ,Amorphous metal ,Hydrogen ,Mechanical Engineering ,Alloy ,Metallurgy ,Metals and Alloys ,chemistry.chemical_element ,engineering.material ,Amorphous solid ,law.invention ,Hydrogen storage ,Chemical engineering ,Amorphous carbon ,chemistry ,Mechanics of Materials ,law ,Materials Chemistry ,engineering ,Crystallization ,Melt spinning - Abstract
Mg–Ni–M (M=Ca, La or Pd) ternary alloys were synthesized by the melt-spinning technique. All as-solidified alloys possessed an amorphous single phase by the additional effect of the third element, though it was difficult to obtain an amorphous Mg 67 Ni 33 binary alloy by melt-spinning. We examined the thermal stability and electrochemical cyclic life property of the ternary amorphous alloys. The crystallization temperature of the amorphous alloys increases with increasing M content. All the alloys except Mg 67 Ni 28 Pd 5 examined in the present study maintain the amorphous structure even after hydrogen absorption at 373 K for Mg–Ni–Ca and Mg–Ni–Pd and at 423 K for Mg–Ni–La. The crystallization temperature increases by absorbing hydrogen, indicating that the alloys are thermally stabilized by hydrogen absorption. In the electrochemical cyclic life measurements up to five cycles, the Mg–Ni–Pd amorphous alloys exhibit high discharge capacities ranging from 100 to 400 mA h/g as well as small cyclic life degradation tendency, though the Mg–Ni–Ca and Mg–Ni–La amorphous alloys possess small discharge capacities of 10–100 mA h/g with significant cyclic life degradation. It is thus concluded that the good cyclic life property of the amorphous hydrogen storage alloys can be obtained by application of the melt-spinning technique to Mg-based alloys with appropriate alloy compositions.
- Published
- 2002
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31. Comparison of traditional and commercial vinegars based on metabolite profiling and antioxidant activity
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Hyang Yeon Kim, Yu Kyung Jang, Mee Youn Lee, Choong Hwan Lee, Seong Yeol Baek, Soo Hwan Yeo, and Sarah Lee
- Subjects
Metabolite ,Ethanol fermentation ,Mass spectrometry ,Applied Microbiology and Biotechnology ,Antioxidants ,Gas Chromatography-Mass Spectrometry ,Anthocyanins ,chemistry.chemical_compound ,Yeast, Dried ,Black raspberry ,Metabolomics ,Sugar ,Acetic Acid ,Principal Component Analysis ,Chromatography ,biology ,General Medicine ,biology.organism_classification ,chemistry ,Fermentation ,Multivariate Analysis ,Quercetin ,Gas chromatography ,Biotechnology - Abstract
Metabolite profiles of seven commercial vinegars and two traditional vinegars were performed by gas chromatography time-of-flight mass spectrometry with multivariate statistical analysis. During alcohol fermentation, yeast, nuruk, and koji were used as sugars for nutrients and as fermentation substrates. Commercial and traditional vinegars were significantly separated in the principal component analysis and orthogonal partial least square discriminant analysis. Six sugars and sugar alcohols, three organic acids, and two other components were selected as different metabolites. Target analysis by ultra-performance liquid chromatography quadruple-time-of-flight mass spectrometry and liquid chromatographyion trap-mass spectrometry/mass spectrometry were used to detect several metabolites having antioxidant activity, such as cyanidin-3-xylosylrutinoside, cyanidin-3-rutinoside, and quercetin, which were mainly detected in Rural Korean Black raspberry vinegar (RKB). These metabolites contributed to the highest antioxidant activity measured in RKB among the nine vinegars. This study revealed that MS-based metabolite profiling was useful in helping to understand the metabolite differences between commercial and traditional vinegars and to evaluate the association between active compounds of vinegar and antioxidant activity.
- Published
- 2014
32. Microstructure and Mechanical Properties of P/M Al-Fe-Cr-Ti-Mm (Mm: Misch Metal) and Al-V-Fe-Mm Alloys
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Teruaki Onogi, Akihisa Inoue, Kazuhiko Kita, Kenichiro Sasamori, Hyang-Yeon Kim, and Hisamichi Kimura
- Subjects
Materials science ,Mechanical Engineering ,Alloy ,Metallurgy ,Metals and Alloys ,chemistry.chemical_element ,engineering.material ,Microstructure ,Industrial and Manufacturing Engineering ,chemistry ,Aluminium ,Phase (matter) ,Powder metallurgy ,Ultimate tensile strength ,Vickers hardness test ,Materials Chemistry ,engineering ,Extrusion ,Composite material - Abstract
Al-Fe-Cr-Ti and Al-V-Fe alloys prepared by the powder metallurgy (P/M) process have high strength exceeding 600 MPa, high-elevated temperature strength exceeding 300 MPa after holding for 100 hours at 573 K and more excellent wear resistance than commercial A390 aluminum alloy. In this work mechanical properties of the P/M Al93Fe3Cr2Ti2 and Al94V4Fe2 alloys were found to be improved by the addition of misch metal (Mm). P/M Al92Fe3Cr2Ti2Mm1 alloys containing quasicrystalline phase were prepared by extrusion of argon gas atomized powders at 673 K, where the atomized powders sieved into the sizes smaller than 75μm were used. The P/M Al92Fe3Cr2Ti2Mm1 alloy has a mixed structure consisting of Al, quasicrystal and compounds phases and exhibits good mechanical properties as follows: ultimate tensile strength (σUTS) of 680±13 MPa, 0.2% proof strength (σ0.2) of 670±10 MPa, plastic elongation (eP) of 0.3±0.1%, Young's modulus (E) of 91±3 GPa and Vickers hardness (Hv) of 230±3, respectively, at room temperature, and alas of 347±5 MPa, σ0.2 of 315±3 MPa and eP of 1.8±0.3%, respectively, after holding for 100 hours at 573 K.
- Published
- 2001
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33. Effect of transition metal (TM) on the crystallization and the magnetic properties of Fe62Co10Si10B13Nb4TM1 melt-spun ribbons
- Author
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Hyang-Yeon Kim
- Subjects
Materials science ,Amorphous metal ,Mechanical Engineering ,Alloy ,Metallurgy ,Amorphous ribbon ,Thermodynamics ,engineering.material ,law.invention ,Atomic radius ,Transition metal ,Mechanics of Materials ,law ,Solid mechanics ,engineering ,Curie temperature ,General Materials Science ,Crystallization - Abstract
Crystallization and magnetic behavior of melt-spun Fe62Co10Si10B13Nb4TM1 amorphous ribbon where TM = Ni, Cr, V, Pd, Pt, Ti, Ta and Zr were examined. The alloy with Pt as transition metal showed the lowest crystallization temperature of 823 K among the studied alloys. Significant increase in crystallization temperature was observed when the atomic radius of the substituted transition metal was varied from that of Pt. High Curie temperature and high saturation magnetization were recognized for the alloys containing Pd, Pt or Ti. The amorphous alloys except the alloys containing Ti or V showed good soft magnetic properties.
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- 2007
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34. Lysophospholipid profile in serum and liver by high-fat diet and tumor induction in obesity-resistant BALB/c mice
- Author
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Hye Min Park, Choong Hwan Lee, Eun Ji Kim, Jiyoung Kim, Hyang Yeon Kim, Minhee Kim, and Jung Han Yoon Park
- Subjects
Male ,medicine.medical_specialty ,Colorectal cancer ,Endocrinology, Diabetes and Metabolism ,Metabolite ,Diet, High-Fat ,BALB/c ,chemistry.chemical_compound ,Metabolomics ,Colon carcinoma ,Internal medicine ,medicine ,Animals ,Obesity ,Mice, Inbred BALB C ,Nutrition and Dietetics ,biology ,Obesity resistant ,food and beverages ,Lysophosphatidylcholines ,High fat diet ,medicine.disease ,biology.organism_classification ,Dietary Fats ,Endocrinology ,chemistry ,Liver ,Tumor progression ,Immunology ,Colonic Neoplasms ,Lysophospholipids - Abstract
Objective: Our previous study revealed that chronic consumption of a high-fat diet (HFD) stimulates colon cancer progression in obesity-resistant BALB/c mice. The aim of the present study was to investigate the significant alteration of metabolites caused by tumor progression and an HFD in the serum and liver in the same mouse model. Methods: Male BALB/c mice were fed either a control diet or a HFD for 20.5 wk. The syngeneic CT26 colon carcinoma cells were injected into the right rear flank of mice after 16 wk of feeding. Metabolites in serum and liver samples were analyzed by ultra-performance liquid chromatographyquadrupole-time-of-flight-mass spectrometry-based metabolomics. Results: HFD feeding and tumor injection induced changes in the choline-containing phospholipids, namely, phosphatidylcholines and lysophosphatidylcholines (lysoPCs), and lysophosphatidylethanolamines in the serum and liver. The majority of these metabolite changes were due to HFD feeding (11 in sera and 5 in livers) rather than tumors (3 in sera and 1 in livers). Conclusion: The HFD- and tumor-related metabolite alterations of phospholipids, especially lysoPCs, in the liver and serum of obesity-resistant mice, suggesting that the lysoPCs are potential biomarkers for the chronic consumption of HFD in nonobese individuals.
- Published
- 2013
35. LC-MS-based chemotaxonomic classification of wild-type Lespedeza sp. and its correlation with genotype
- Author
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Jae Won Lee, Changyoung Lee, Young-Mi Kim, Nahyun Kim, Joongku Lee, Hyang Yeon Kim, Dong Hyuk Lee, Dongho Lee, Sang Hong Park, and Choong Hwan Lee
- Subjects
Spectrometry, Mass, Electrospray Ionization ,DNA, Plant ,Genotype ,Sequence analysis ,Plant genetics ,Plant Science ,Lespedeza ,Species Specificity ,Phylogenetics ,Botany ,DNA, Ribosomal Spacer ,Cluster Analysis ,Metabolomics ,Internal transcribed spacer ,Least-Squares Analysis ,Chromatography, High Pressure Liquid ,Phylogeny ,Principal Component Analysis ,Lespedeza cuneata ,biology ,Phylogenetic tree ,Plant Stems ,Plant Extracts ,DNA, Chloroplast ,Discriminant Analysis ,General Medicine ,Sequence Analysis, DNA ,biology.organism_classification ,Plant Leaves ,Phenotype ,Principal component analysis ,Multivariate Analysis ,Metabolome ,Agronomy and Crop Science - Abstract
In this study, 39 specimens belonging to Lespedeza species (Lespedeza cyrtobotrya, L. bicolor, L. maximowiczii, and Lespedeza cuneata) (Leguminosae) were classified phenotypically and genotypically. We constructed a phylogenetic tree based on the combined nrDNA (internal transcribed spacer; ITS) and cpDNA (trnL-trnF) sequences with the aim of classifying the genotypes. Samples were mainly divided into three genotypes. Samples of L. cyrtobotrya and L. bicolor were mixed in a single branch, whereas samples of L. maximowiczii and L. cuneata were clustered within species, respectively. We performed a liquid chromatography-electrospray ionization-mass spectrometry-based metabolite profiling analysis to classify the phenotypes. Multivariate statistical analyses such as principal component analysis (PCA) and hierarchical clustering analysis (HCA) were used for the clustering pattern analysis and distance analysis between species, respectively. According to the PCA and HCA results, leaves were classified into four phenotypes according to species. In both the genetic and chemotaxonomic classification methods, the distance between L. cyrtobotrya and L. bicolor was the closest between species, and L. cuneata was the farthest away from the other three species. Additionally, orthogonal partial least squares-discriminant analysis was employed to identify significantly different phytochemicals between species. We classified L. cyrtobotrya and L. bicolor by identifying significantly different phytochemicals. Interestingly, leaves and stems showed different phenotypic classifications based on the chemotaxonomic classification. Stem samples of the other three species were mixed regardless of species, whereas L. cyrtobotrya stem samples were clustered within species. The phenotypic classification of leaves coincided more with the genotypic classification than that of stems. Key message We classified four wild-type Lespedeza sp. by analyzing the combined nrDNA (ITS) and cpDNA (trnL-trnF) sequences. We also classified leaves and stems of Lespedeza sp. by applying liquid chromatography-mass spectroscopy-based metabolite profiling.
- Published
- 2012
36. Mass spectrometry-based chemotaxonomic classification of Penicillium species (P. echinulatum, P. expansum, P. solitum, and P. oxalicum) and its correlation with antioxidant activity
- Author
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Choong Hwan Lee, Hyang Yeon Kim, and Hye Min Park
- Subjects
Microbiology (medical) ,Spectrometry, Mass, Electrospray Ionization ,Metabolite ,Microbiology ,Gas Chromatography-Mass Spectrometry ,chemistry.chemical_compound ,Species Specificity ,Andrastin A ,DNA, Ribosomal Spacer ,Benzothiazoles ,Molecular Biology ,Phylogeny ,Oxaline ,Chromatography ,biology ,Dendrogram ,Penicillium ,Free Radical Scavengers ,Sequence Analysis, DNA ,biology.organism_classification ,chemistry ,Chemotaxonomy ,Multivariate Analysis ,Gluconic acid ,Metabolome ,Sulfonic Acids ,Salicylic acid ,Biomarkers - Abstract
In this study, 4 Penicillium species (17 strains) were classified on the basis of metabolite profile (chemotaxonomy) by using liquid chromatography-electrospray ionization ion trap-mass spectrometry (LC-ESI-MS), gas chromatography-ion trap-mass spectrometry (GC-IT-MS) and multivariate statistical analysis. The LC-ESI-MS-based dendrogram was similar to the internal transcribed spacer (ITS)-based dendrogram, in that Penicillium oxalicum was separated from the other 3 species. Moreover, vermiculidiol, meleagrin, oxaline, glandicolin A and B, and secalonic acid D were identified as metabolites that enable discrimination of Penicillium species by partial least squares discriminant analysis (PLS-DA). Evaluation of the species-specific metabolites produced by P. expansum, P. echinulatum, and P. solitum revealed that the 3 species differed from each other. On the other hand, GC-IT-MS-based dendrogram revealed that P. expansum was clearly classified separately from the other 3 species, and this result correlated with the antioxidant activity of the 4 species: P. expansum had a higher radical scavenging activity than the other 3 species. The metabolites produced in higher amounts in P. expansum were gluconic acid (12, 29, 33); andrastin A (16), B (15), and C (17); chaetoglobosin C (14), a class of sugar (31, 32); and salicylic acid (28). The results of this study demonstrated that metabolite-based chemotaxonomy could be used not only as a classification method but also as a tool for evaluation of species-specific activities.
- Published
- 2012
37. Antimicrobial compounds profile during Cheonggukjang fermentation against Xanthomonas oryzae pv. oryzae (Xoo)
- Author
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Choong Hwan Lee, Hyang Yeon Kim, Maria John Muthaiya, Gun Hee Son, Ji-Young Kim, and Sarah Lee
- Subjects
Models, Molecular ,Xanthomonas ,Bacillus ,Applied Microbiology and Biotechnology ,Mass Spectrometry ,Microbiology ,chemistry.chemical_compound ,Xanthomonas oryzae ,Xanthomonas oryzae pv. oryzae ,Chromatography, High Pressure Liquid ,biology ,Molecular Structure ,Daidzein ,food and beverages ,Oryza ,General Medicine ,Glycitein ,biology.organism_classification ,Antimicrobial ,Anti-Bacterial Agents ,Molecular Weight ,chemistry ,Fermentation ,Food Microbiology ,lipids (amino acids, peptides, and proteins) ,Soybeans ,Surfactin ,Bacteria ,Biotechnology - Abstract
Xanthomonas oryzae causes rice bacterial blight, which has been reported as one of the most destructive diseases of rice. Metabolites were identified through cheonggukjang, a traditional Korean fermented soybean product fermented by the Bacillus spp., to control the bacteria. HPLC, MS, and UPLC-Q-TOF-MS analyses were performed to identify metabolites responsible for antimicrobial activity. In this analysis, the m/z values of 253.0498, 283.0600, 269.0455, 992.6287, and 1,006.6436 were identified as daidzein, glycitein, genistein, surfactin B, and surfactin A, respectively. The levels of surfactin B and surfactin A were found to be high at 24 h (4.35 μg/ml) and 36 h (3.43 μg/ml) of fermentation, respectively.
- Published
- 2011
38. Laboratory and field evaluations of entomopathogenic Lecanicillium attenuatum CNU-23 for control of green peach aphid (Myzus persicae)
- Author
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Hyang Yeon, Kim, Hyang Burm, Lee, Young Cheol, Kim, and In Seon, Kim
- Subjects
Aphids ,Hypocreales ,RNA, Ribosomal, 18S ,Animals ,DNA, Intergenic ,Capsicum ,Pest Control, Biological ,Phylogeny - Abstract
An entomopathogenic fungus was isolated from an infected aphid. The isolate conformed most closely to Lecanicillium attenuatum CBS 402.78 (AJ292434) based on the internal transcribed spacer (ITS) region of its 18S rDNA, and thus was designated L. attenuatum CNU-23. Laboratory and field evaluations of CNU-23 blastospores were carried out for the control of green peach aphids. The laboratory evaluations of CNU-23 revealed an aphid mortality of about 80% with an estimated LT50 of 3.72 days after the application of CNU-23 at 1x106 blastospores/ ml. Meanwhile, the field evaluations of CNU-23 performed on greenhouse pepper plants during the rainy season showed an aphid mortality ranging from 72% to 97%. Significant sporulation was observed in the aphids treated with CNU-23. Therefore, the results suggest that L. attenuatum CNU-23 can be used as a biocontrol agent for green peach aphids on greenhouse pepper plants.
- Published
- 2009
39. Metabolite Profiling Reveals the Effect of Dietary Rubus coreanus Vinegar on Ovariectomy-Induced Osteoporosis in a Rat Model
- Author
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Soo Hwan Yeo, Seong Yeol Baek, Digar Singh, Mee Youn Lee, Choong Hwan Lee, Hyang Yeon Kim, and Yoo Kyoung Park
- Subjects
0301 basic medicine ,Metabolite ,Osteoporosis ,Pharmaceutical Science ,Rubus coreanus ,Phenylalanine ,Analytical Chemistry ,Butyric acid ,chemistry.chemical_compound ,0302 clinical medicine ,Drug Discovery ,Osteoporosis, Postmenopausal ,Acetic Acid ,mass spectrometry ,Alendronate ,biology ,ovariectomy ,multivariate analysis ,Chemistry (miscellaneous) ,030220 oncology & carcinogenesis ,Metabolome ,Ovariectomized rat ,Molecular Medicine ,Female ,Rubus coreanus vinegar ,medicine.medical_specialty ,Gas Chromatography-Mass Spectrometry ,Article ,lcsh:QD241-441 ,03 medical and health sciences ,Acetic acid ,lcsh:Organic chemistry ,Internal medicine ,medicine ,Animals ,Humans ,Physical and Theoretical Chemistry ,Dose-Response Relationship, Drug ,Plant Extracts ,Organic Chemistry ,medicine.disease ,biology.organism_classification ,osteoporosis ,Rats ,Disease Models, Animal ,030104 developmental biology ,Endocrinology ,chemistry ,Rubus - Abstract
The study was aimed at exploring the curative effects of Rubus coreanus (RC) vinegar against postmenopausal osteoporosis by using ovariectomized rats as a model. The investigations were performed in five groups: sham, ovariectomized (OVX) rats without treatment, low-dose RC vinegar (LRV)-treated OVX rats, high-dose RC vinegar (HRV)-treated OVX rats and alendronate (ALEN)-treated OVX rats. The efficacy of RC vinegar was evaluated using physical, biochemical, histological and metabolomic parameters. Compared to the OVX rats, the LRV and HRV groups showed positive effects on the aforementioned parameters, indicating estrogen regulation. Plasma metabolome analysis of the groups using gas chromatography-time of flight mass spectrometry (GC-TOF-MS) and ultra-performance liquid chromatography quadrupole-TOF-MS (UPLC-Q-TOF-MS) with multivariate analysis revealed 19 and 16 metabolites, respectively. Notably, the levels of butyric acid, phenylalanine, glucose, tryptophan and some lysophosphatidylcholines were marginally increased in RC vinegar-treated groups compared to OVX. However, the pattern of metabolite levels in RC vinegar-treated groups was found similar to ALEN, but differed significantly from that in sham group. The results highlight the prophylactic and curative potential of dietary vinegar against postmenopausal osteoporosis. RC vinegar could be an effective natural alternative for the prevention of postmenopausal osteoporosis.
- Published
- 2016
- Full Text
- View/download PDF
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