37 results on '"Young Yu"'
Search Results
2. A retrospective study on the incidence, management and risk factors of skin rash in patients with advanced prostate cancer in Japan
- Author
-
Raf De Moor, Yosuke Koroki, David Bin-Chia Wu, Dae Young Yu, Mikiko Tohyama, and Chikara Ohyama
- Subjects
Reproductive Medicine ,Urology ,General Medicine - Abstract
Background Worldwide, prostate cancer (PC) is the second most diagnosed cancer and the fifth leading cause of cancer death in men. Hormonal therapies, commonly used for PC, are associated with a range of treatment-emergent adverse events (TEAEs). The population from Japan seems to be at higher risk of developing TEAEs of skin rash compared to the overall global population. This study was conducted to get a better insight into the incidence, management, and risk factors for skin rash during active treatment for advanced PC in Japan. Methods A retrospective cohort of PC patients was identified and subsequently categorized, into non-metastatic and metastatic castration-resistant prostate cancer patients (nmCRPC and mCRPC), and metastatic castration-naïve prostate cancer patients (mCNPC). The analysis was based on a dataset from the Medical Data Vision (MDV) database. Descriptive statistics were determined, and a multivariate Cox proportional hazards model was used to the associated risk factors for the onset of rash. Results Overall, 1,738 nmCRPC patients, 630 mCRPC patients, and 454 mCNPC patients were included in this analysis. The median age was 78 years old and similar across the three cohorts. The skin rash incidence was 19.97% for nmCRPC cohort, 28.89% for mCRPC cohort, and 28.85% for mCNPC cohort. The median duration of skin rash ranged from 29 to 42 days. Statistically significant risk factors for developing skin rash included a history of allergy or hypersensitivity (all cohorts), increased age (nmCRPC and mCRPC), a body mass index (BMI) of Conclusion This study provides a better understanding of the real-world incidence, onset, duration, management and risk factors of skin rash in patients on active PC treatment in Japan. It was observed that approximately 20–30% of PC patients experience skin rash. Development of skin rash was associated with previous allergy or hypersensitivity, BMI of
- Published
- 2023
3. The Relationship between the Drug Delivery Properties of a Formulation of Teriparatide Microneedles and the Pharmacokinetic Evaluation of Teriparatide Administration in Rats
- Author
-
Yu-Jeong, Oh, Nae-Won, Kang, Hye-Rin, Jeong, Seo-Yeon, Sohn, Yae-Eun, Jeon, Na-Young, Yu, Yura, Hwang, Sunkyung, Kim, Dae-Duk, Kim, and Jung-Hwan, Park
- Subjects
Pharmacology ,Sucrose ,Microinjections ,Swine ,Organic Chemistry ,Pharmaceutical Science ,Administration, Cutaneous ,Rats ,Drug Delivery Systems ,Pharmaceutical Preparations ,Needles ,Carboxymethylcellulose Sodium ,Teriparatide ,Animals ,Molecular Medicine ,Pharmacology (medical) ,Skin ,Biotechnology - Abstract
Teriparatide is an effective drug for the treatment of osteoporosis. This study examines the relationship between the drug delivery properties of the solid formulation with teriparatide and the pharmacokinetic properties of teriparatide in vivo.Teriparatide microneedles with different dissolution rates were prepared using sucrose and carboxymethylcellulose (CMC). There were three aspects of this study: (1) The dissolution rate of teriparatide from both formulations (sucrose and CMC) was measured in vitro. (2) After administration into porcine skin ex vivo, the diffusion rate of FITC-dextran was observed using a confocal microscope. (3) Pharmacokinetic studies were performed in rats and pharmacokinetic data compared with the release rate and the diffusion pattern.In the in vitro dissolution experiment, 80% of teriparatide was released within 30 min from the CMC MNs, whereas 80% of teriparatide was released within 10 min from the sucrose MNs. After 30 min, the fluorescence intensity on the surface of the MNs was 40% of the initial intensity for sucrose MNs and 90% for CMC MNs. In the pharmacokinetic study, the CWhen teriparatide is delivered into the skin using microneedles, the release rate from the solid formulation determines the drug's pharmacokinetic properties. The diffusion pattern of fluorescence into the skin can be used to anticipate the pharmacokinetic properties of the drug.
- Published
- 2022
4. Ultrasensitive and Highly Stretchable Multiple-Crosslinked Ionic Hydrogel Sensors with Long-Term Stability
- Author
-
Jin-Young Yu, Seung Eon Moon, Jeong Hun Kim, and Seong Min Kang
- Subjects
Electrical and Electronic Engineering ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Abstract
Flexible hydrogels are receiving significant attention for their application in wearable sensors. However, most hydrogel materials exhibit weak and one-time adhesion, low sensitivity, ice crystallization, water evaporation, and poor self-recovery, thereby limiting their application as sensors. These issues are only partly addressed in previous studies. Herein, a multiple-crosslinked poly(2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide-co-acrylamide) (P(SBMA-co-AAm)) multifunctional hydrogel is prepared via a one-pot synthesis method to overcome the aforementioned limitations. Specifically, ions, glycerol, and 2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide are incorporated to reduce the freezing point and improve the moisture retention ability. The proposed hydrogel is superior to existing hydrogels because it exhibits good stretchability (a strain of 2900%), self-healing properties, and transparency through effective energy dissipation in its dynamic crosslinked network. Further, 2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide as a zwitterion monomer results in an excellent gauge factor of 43.4 at strains of 1300–1600% by improving the ion transportability and achieving a strong adhesion of 20.9 kPa owing to the dipole–dipole moment. The proposed hydrogel is promising for next-generation biomedical applications, such as soft robots, and health monitoring.
- Published
- 2023
5. Analysis of NVMe over fabrics with SCinet DTN-as-a-Service
- Author
-
Xiao Wang, Jim Chen, Se-young Yu, Fei Yeh, Anna Giannakou, Marc Lyonnais, Joe Mambretti, and Eric Pouyoul
- Subjects
Service (systems architecture) ,Computer Networks and Communications ,business.industry ,Computer science ,Distributed computing ,NVM Express ,Big data ,Volume (computing) ,Supercomputer ,Wide area ,business ,Computer communication networks ,Software ,Data transmission - Abstract
Supporting transfers of science big data over Wide Area Networks (WANs) with Data Transfer Nodes (DTNs) requires optimizing multiple parameters within the underlying infrastructure. New solutions for such data movement require new paradigms and technologies, such as NVMe over Fabrics, which provides high-performance data movement with direct remote NVMe device access over traditional fabrics. However, recent NVMe over Fabrics studies have been limited to local storage fabrics. To support increasing demands for the large volume of science data movement during Supercomputing (SC) conferences, we proposed a SCinet DTN-as-a-Service framework orchestrating the desired optimization to meet users, applications, and providers’ requirements. Furthermore, we extend the SCinet DTN-as-a-Service framework to incorporate new techniques, solve optimization issues in data-intensive science and evaluate NVMe over Fabrics with multiple WAN testbeds to examine its performance and discover new opportunities for optimization.
- Published
- 2021
6. Automatic segmentation of corneal dystrophy on photographic images based on texture analysis
- Author
-
Seul Ki Bang, Kyung Hyun Jin, Jang Ryul Park, Wang-Yuhl Oh, Jong In You, Ki-Young Kim, and Seung-Young Yu
- Subjects
genetic structures ,Iris ,Corneal dystrophy ,Texture (music) ,Pupil ,Cornea ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,medicine ,Humans ,Iris (anatomy) ,Corneal Dystrophies, Hereditary ,business.industry ,Dystrophy ,Pattern recognition ,medicine.disease ,eye diseases ,Pearson product-moment correlation coefficient ,Ophthalmology ,medicine.anatomical_structure ,030221 ophthalmology & optometry ,symbols ,Automatic segmentation ,sense organs ,Artificial intelligence ,business ,Algorithms ,030217 neurology & neurosurgery - Abstract
To develop an automatic algorithm to analyze dystrophic lesions on photographic images of corneal dystrophy. The dataset included 32 images of corneal dystrophy. The dystrophic area was manually segmented twice. Manually labeled dystrophy areas were compared with automatically segmented images. First, we manually removed the light reflex from the image of the cornea. Using an automatic approach, we extracted the brown color of the iris. Then, the program detected the circular region of the pupil and the corneal surface. A whitish dystrophy area was defined based on the image intensity on the iris and the pupil. The sliding square kernel was applied to clearly define the dystrophic region. For the manual analysis and the twice automatic approach, the Dice similarity was 0.804 and 0.801, respectively. The Pearson correlation coefficient was 0.807 and 0.806, respectively. The total number of distinct dystrophic areas showed no significant difference between the manual and automatic approaches according to the Wilcoxon signed-rank test (p
- Published
- 2021
7. Reciprocal impacts of telomerase activity and ADRN/MES differentiation state in neuroblastoma tumor biology
- Author
-
Syed S. Zahid, Xi Kathy Zhou, Eun Young Yu, Neal F. Lue, Nai-Kong V. Cheung, Sarah Aloe, and Erik Falck-Pedersen
- Subjects
Telomerase ,animal structures ,QH301-705.5 ,Cell ,Medicine (miscellaneous) ,Development ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,Paediatric cancer ,Neuroblastoma ,Cancer epigenetics ,Cell Line, Tumor ,Cancer genomics ,medicine ,Humans ,Biology (General) ,Gene ,Innate immune system ,Mesenchymal stem cell ,Cell Differentiation ,Mesenchymal Stem Cells ,medicine.disease ,In vitro ,Telomere ,Cell biology ,Telomeres ,medicine.anatomical_structure ,General Agricultural and Biological Sciences - Abstract
Telomere maintenance and tumor cell differentiation have been separately implicated in neuroblastoma malignancy. Their mechanistic connection is unclear. We analyzed neuroblastoma cell lines and morphologic subclones representing the adrenergic (ADRN) and mesenchymal (MES) differentiation states and uncovered sharp differences in their telomere protein and telomerase activity levels. Pharmacologic conversion of ADRN into MES cells elicited consistent and robust changes in the expression of telomere-related proteins. Conversely, stringent down-regulation of telomerase activity triggers the differentiation of ADRN into MES cells, which was reversible upon telomerase up-regulation. Interestingly, the MES differentiation state is associated with elevated levels of innate immunity factors, including key components of the DNA-sensing pathway. Accordingly, MES but not ADRN cells can mount a robust response to viral infections in vitro. A gene expression signature based on telomere and cell lineage-related factors can cluster neuroblastoma tumor samples into predominantly ADRN or MES-like groups, with distinct clinical outcomes. Our findings establish a strong mechanistic connection between telomere and differentiation and suggest that manipulating telomeres may suppress malignancy not only by limiting the tumor growth potential but also by inducing tumor cell differentiation and altering its immunogenicity., Yu et al. identify marked differences in the telomere and immunologic profiles of neuroblastoma cell lines displaying MES and ADRN lineage characteristics. They show that pharmacologically converting ADRN into MES cells triggers associated switch in telomere/immunologic protein profiles whereas inhibiting telomerase activity in ADRN cells induces reversible conversion into MES cells.
- Published
- 2021
8. Progressive retinal neurodegeneration and microvascular change in diabetic retinopathy: longitudinal study using OCT angiography
- Author
-
Do Gyun Kim, Eung Suk Kim, Seung-Young Yu, and Ki-Young Kim
- Subjects
Male ,medicine.medical_specialty ,Longitudinal study ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,030204 cardiovascular system & hematology ,Retina ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,Oct angiography ,Diabetic Neuropathies ,Ophthalmology ,Diabetes Mellitus ,Internal Medicine ,medicine ,Humans ,Macula Lutea ,Longitudinal Studies ,Fluorescein Angiography ,Aged ,Retrospective Studies ,Diabetic Retinopathy ,business.industry ,Neurodegeneration ,Retinal Vessels ,Retrospective cohort study ,Retinal ,General Medicine ,Diabetic retinopathy ,Middle Aged ,medicine.disease ,Inner plexiform layer ,Ganglion ,medicine.anatomical_structure ,chemistry ,Case-Control Studies ,Nerve Degeneration ,Disease Progression ,Female ,sense organs ,business ,Diabetic Angiopathies ,Tomography, Optical Coherence ,Retinal Neurons - Abstract
To investigate the association between progressive macular ganglion cell/inner plexiform layer (mGCIPL) thinning and change of optical coherence tomography angiography (OCTA)-derived microvascular parameters in early-stage diabetic retinopathy (DR). A retrospective cohort study involved 40 eyes presenting with no DR or mild non-proliferative DR at baseline, and 30 healthy controls were included. All participants underwent spectral-domain OCT and OCTA at baseline and at 6, 12, 18, and 24 months. Change of mGCIPL thickness and OCTA metrics including foveal avascular zone (FAZ) area and FAZ circularity, vessel density (VD), and perfusion index (PI) was measured. Correlations between mGCIPL thickness and OCTA metrics were explored using regression models. Average progressive mGCIPL loss was 0.45 µm per year. Three microvascular parameters were significantly impaired at 24 months compared to baseline (FAZ area: 0.34–0.36 mm2, VD: 18.9–18.5/mm, PI: 0.35–0.34). A strong positive correlation was found between loss of mGCIPL and VD from baseline to 24 months (r = 0.817, p
- Published
- 2019
9. Optimization of pulsed current in resistance spot welding of Zn-coated hot-stamped boron steels
- Author
-
Vijeesh Vijayan, Joo Yong Cheon, Yeong-Do Park, Ji Young Yu, Jae-Hun Kim, Changwook Ji, and Sivaprasad Murgun
- Subjects
Materials science ,Mechanical Engineering ,Contact resistance ,Metallurgy ,Weldability ,Welding ,law.invention ,Surface coating ,Mechanics of Materials ,law ,Faying surface ,Contact area ,Spot welding ,Nugget Formation - Abstract
Metallic coatings have been widely used for hot-stamped boron steel in automotive applications. Surface coating in hot-stamped boron steels has improved corrosion resistance. However, a thick coating layer degrades resistance spot weldability. In the case of a Zn-coated hot-stamped boron steel, the high contact resistance and material stiffness with low vaporization temperature of the alloyed layers result in a narrow current passage at the faying surface. Expulsion occurs at low current due to rapid heat development, resulting in a narrow weld current range. The pulsed current can control the heat input by applying a fast cool time during welding to improve the mechanical properties of the joint and acceptable current range. In this study, Zn-coated hot-stamped steels were resistance spot welded using various pulse current procedures, and welding condition was optimized via three pulsed current steps. Step 1: Contact area was controlled without nugget formation. Step 2: Nugget growth was minimized and contact area was maximized. Step 3: The maximum acceptable current range and nugget diameter were achieved. These welding conditions improved the acceptable current range and mechanical properties of spot welds due to increased spot weld size.
- Published
- 2019
10. Central serous chorioretinopathy in elderly subjects: angiographic and tomographic characteristics
- Author
-
Seung-Young Yu, Kyung Tae Kim, Eung Suk Kim, Se Woong Kang, Kunho Bae, Seung Wan Nam, and Sang Jin Kim
- Subjects
Adult ,Male ,Fovea Centralis ,medicine.medical_specialty ,Fundus Oculi ,Indocyanine green angiography ,Visual Acuity ,Spectral domain ,Retinal Pigment Epithelium ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,0302 clinical medicine ,Depigmentation ,Ophthalmology ,Humans ,Medicine ,Fluorescein Angiography ,Aged ,Retrospective Studies ,030304 developmental biology ,0303 health sciences ,Retinal pigment epithelium ,medicine.diagnostic_test ,Choroid ,business.industry ,Retinal ,Middle Aged ,Fluorescein angiography ,eye diseases ,Sensory Systems ,Serous fluid ,medicine.anatomical_structure ,Central Serous Chorioretinopathy ,chemistry ,030221 ophthalmology & optometry ,Female ,sense organs ,medicine.symptom ,Subretinal fluid ,business ,Tomography, Optical Coherence ,Follow-Up Studies - Abstract
To investigate the angiographic, tomographic, and clinical characteristics of idiopathic central serous chorioretinopathy (CSC) in elderly patients. The patients were divided into two groups according to a cutoff age of 60 years at baseline. Patients underwent spectral domain optical coherence tomography, fluorescein angiography, and indocyanine green angiography. Angiographic and tomographic features were compared between the two groups (young vs. elderly group). Of 176 patients, 26 patients (15.1%) were 60 years or older. Complete resolution of subretinal fluid after treatment was noted in 72.0% of the elderly group and 90.8% of the young group (P = 0.021). The elderly group showed worse baseline and final vision, more bilateral involvement, and lower male preponderance than the young group (P
- Published
- 2018
11. Longitudinal changes in retinal microvasculature after panretinal photocoagulation in diabetic retinopathy using swept-source OCT angiography
- Author
-
Ki-Young Kim, Seung-Young Yu, and Eung Suk Kim
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Capillary plexus ,Science ,Light Coagulation ,Panretinal photocoagulation ,Article ,Retina ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Oct angiography ,Ophthalmology ,Humans ,Medicine ,Longitudinal Studies ,Diabetic Retinopathy ,Multidisciplinary ,business.industry ,Length density ,Diabetes ,Retinal ,Diabetic retinopathy ,Foveal avascular zone ,Middle Aged ,medicine.disease ,Retinal diseases ,030104 developmental biology ,chemistry ,Microvessels ,030221 ophthalmology & optometry ,Female ,sense organs ,business ,Perfusion ,Tomography, Optical Coherence - Abstract
This study evaluated quantitative changes in microvascular parameters after panretinal photocoagulation (PRP) in diabetic retinopathy (DR), using swept-source OCT Angiography (SS-OCTA). A total of 27 treatment-naïve eyes were subjected to PRP and followed-up for > 12 months after the procedure. Foveal avascular zone (FAZ) area, macular perfusion density (PD), and vessel length density (VLD) were calculated on a 3 × 3 mm en face OCTA image and nonperfusion area (NPA) was obtained on a 12 × 12 mm en face OCTA image. One month after PRP, PD and VLD of superficial and deep capillary plexus decreased and subsequently, increased progressively across the next 12 months, with statistically significant differences (P = 0.015 and 0.02). Continuous decreasing trends in total NPA values was observed across 12 months after PRP (P = 0.125). A difference in PD of the superficial capillary plexus between baseline and 6 months post PRP, was significantly associated with the progression of DR, 12 months after PRP (OR 0.528; P = 0.025). We found significant longitudinal retinal microvascular changes after PRP in DR. Overall macular perfusion status was impaired and progressively recovered across the next 12 months, compared to the baseline. Additionally, the early treatment responses in PD can predict the long-term outcomes of PDR after PRP.
- Published
- 2021
12. Two-dimensional amine and hydroxy functionalized fused aromatic covalent organic framework
- Author
-
Hyung-Joon Shin, Jeong-Min Seo, Ishfaq Ahmad, Javeed Mahmood, Jong-Beom Baek, Hyuk-Jun Noh, Minbok Jung, Soo-Young Yu, and Young Hyun Kim
- Subjects
010405 organic chemistry ,Chemistry ,Aromatization ,Dynamic covalent chemistry ,General Chemistry ,Crystal structure ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,Biochemistry ,eye diseases ,Reversible reaction ,0104 chemical sciences ,lcsh:Chemistry ,Crystallinity ,lcsh:QD1-999 ,Covalent bond ,Polymer chemistry ,Materials Chemistry ,Environmental Chemistry ,sense organs ,Covalent organic framework - Abstract
Ordered two-dimensional covalent organic frameworks (COFs) have generally been synthesized using reversible reactions. It has been difficult to synthesize a similar degree of ordered COFs using irreversible reactions. Developing COFs with a fused aromatic ring system via an irreversible reaction is highly desirable but has remained a significant challenge. Here we demonstrate a COF that can be synthesized from organic building blocks via irreversible condensation (aromatization). The as-synthesized robust fused aromatic COF (F-COF) exhibits high crystallinity. Its lattice structure is characterized by scanning tunneling microscopy and X-ray diffraction pattern. Because of its fused aromatic ring system, the F-COF structure possesses high physiochemical stability, due to the absence of hydrolysable weak covalent bonds. Two-dimensional covalent organic frameworks (2D COFs) are commonly synthesised through dynamic covalent chemistry, as it allows for thermodynamic ‘error correction' which enhances crystallinity. Here a crystalline 2D COF with amine and hydroxyl functional groups within the pores is synthesised through kinetically-controlled reactions.
- Published
- 2020
13. Simplified Technique for Predicting Offshore Pipeline Expansion
- Author
-
Do Kyun Kim, Junhyeon Seo, Kee-Cheol Park, Han-Suk Choi, and Su Young Yu
- Subjects
Computer science ,020209 energy ,Mechanical Engineering ,Flow assurance ,Process (computing) ,020101 civil engineering ,Ocean Engineering ,02 engineering and technology ,Pipeline (software) ,0201 civil engineering ,Pipeline transport ,Lead (geology) ,Offshore geotechnical engineering ,0202 electrical engineering, electronic engineering, information engineering ,Submarine pipeline ,Marine engineering ,Subsea - Abstract
In this study, we propose a method for estimating the amount of expansion that occurs in subsea pipelines, which could be applied in the design of robust structures that transport oil and gas from offshore wells. We begin with a literature review and general discussion of existing estimation methods and terminologies with respect to subsea pipelines. Due to the effects of high pressure and high temperature, the production of fluid from offshore wells is typically caused by physical deformation of subsea structures, e.g., expansion and contraction during the transportation process. In severe cases, vertical and lateral buckling occurs, which causes a significant negative impact on structural safety, and which is related to on-bottom stability, free-span, structural collapse, and many other factors. In addition, these factors may affect the production rate with respect to flow assurance, wax, and hydration, to name a few. In this study, we developed a simple and efficient method for generating a reliable pipe expansion design in the early stage, which can lead to savings in both cost and computation time. As such, in this paper, we propose an applicable diagram, which we call the standard dimensionless ratio (SDR) versus virtual anchor length (LA) diagram, that utilizes an efficient procedure for estimating subsea pipeline expansion based on applied reliable scenarios. With this user guideline, offshore pipeline structural designers can reliably determine the amount of subsea pipeline expansion and the obtained results will also be useful for the installation, design, and maintenance of the subsea pipeline.
- Published
- 2018
14. Changes in aqueous concentrations of various cytokines after intravitreal bevacizumab and subtenon triamcinolone injection for diabetic macular edema
- Author
-
Dae Yeong Lee, Dong Heun Nam, and Seung-Young Yu
- Subjects
Male ,0301 basic medicine ,genetic structures ,Tenon Capsule ,medicine.medical_treatment ,Visual Acuity ,Angiogenesis Inhibitors ,Triamcinolone Acetonide ,chemistry.chemical_compound ,0302 clinical medicine ,Macula Lutea ,Prospective Studies ,Interleukin ,Middle Aged ,Sensory Systems ,Bevacizumab ,Vascular endothelial growth factor ,Treatment Outcome ,Cytokine ,medicine.anatomical_structure ,Intravitreal Injections ,Cytokines ,Female ,Injections, Intraocular ,Tomography, Optical Coherence ,medicine.drug ,Adult ,medicine.medical_specialty ,Combination therapy ,Macular Edema ,Aqueous Humor ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Ophthalmology ,medicine ,Humans ,Glucocorticoids ,Aged ,Diabetic Retinopathy ,business.industry ,Growth factor ,Monocyte ,Therapeutic effect ,eye diseases ,030104 developmental biology ,chemistry ,030221 ophthalmology & optometry ,business ,Follow-Up Studies - Abstract
The purpose of this study was to compare the changes in the aqueous cytokine levels after intravitreal bevacizumab with those after combined intravitreal bevacizumab and subtenon triamcinolone injection in diabetic macular edema (DME). This study examined 24 eyes of 23 patients with DME. Each patient with DME received randomly either an intravitreal injection of bevacizumab (IVBe) or IVBe with a subtenon triamcinolone injection (IVBe + STTA). Best corrected visual acuity and foveal thickness were evaluated and aqueous samples were obtained before and 4 weeks after the injection. The aqueous concentrations of interleukin (IL)-6, IL-8, interferon-induced protein (IP)-10, monocyte chemotactic protein (MCP)-1, platelet-derived growth factor (PDGF)-AA, and vascular endothelial growth factor (VEGF) were measured using a multiplex bead assay. After the injection, the foveal thickness decreased more in the IVBe + STTA group than in the IVBe group (P = 0.042). The MCP-1, PDGF-AA, and VEGF levels decreased significantly in the IVBe + STTA group (p = 0.013, p = 0.004 and p = 0.018 respectively), but only the VEGF level decreased in the IVBe group (p = 0.001). IL-8 was significantly increased in the IVBe + STTA group (p = 0.003) but the changes in the VEGF levels were smaller than in the IVBe group (p = 0.025). Intravitreal bevacizumab and subtenon triamcinolone injection reduces the VEGF, MCP-1 and PDGF-AA levels and increases the IL-8 level in the plural cytokine profiles of patients with DME, which might explain the limited therapeutic effect of combination therapy.
- Published
- 2017
15. Automatic detection of major depressive disorder using electrodermal activity
- Author
-
Seunghwan Kim, Han Young Yu, Sangwon Byun, Ah Young Kim, Hong Jin Jeon, Eun Hye Jang, and Kwan Woo Choi
- Subjects
Adult ,Male ,medicine.medical_specialty ,Support Vector Machine ,lcsh:Medicine ,Feature selection ,Audiology ,Mental arithmetic ,Sensitivity and Specificity ,Article ,Arousal ,Automation ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Medicine ,lcsh:Science ,Depressive symptoms ,Depressive Disorder, Major ,Multidisciplinary ,business.industry ,Autonomic arousal ,Decision tree learning ,lcsh:R ,Reproducibility of Results ,Diagnostic marker ,Galvanic Skin Response ,Middle Aged ,medicine.disease ,030227 psychiatry ,Case-Control Studies ,Major depressive disorder ,Female ,lcsh:Q ,business ,030217 neurology & neurosurgery - Abstract
Major depressive disorder (MDD) is a common psychiatric disorder and the leading cause of disability worldwide. However, current methods used to diagnose depression mainly rely on clinical interviews and self-reported scales of depressive symptoms, which lack objectivity and efficiency. To address this challenge, we present a machine learning approach to screen for MDD using electrodermal activity (EDA). Participants included 30 patients with MDD and 37 healthy controls. Their EDA was measured during five experimental phases consisted of baseline, mental arithmetic task, recovery from the stress task, relaxation task, and recovery from the relaxation task, which elicited multiple alterations in autonomic activity. Selected EDA features were extracted from each phase, and differential EDA features between two distinct phases were evaluated. By using these features as input data and performing feature selection with SVM-RFE, 74% accuracy, 74% sensitivity, and 71% specificity could be achieved by our decision tree classifier. The most relevant features selected by SVM-RFE included differential EDA features and features from the stress and relaxation tasks. These findings suggest that automatic detection of depression based on EDA features is feasible and that monitoring changes in physiological signal when a subject is experiencing autonomic arousal and recovery may enhance discrimination power.
- Published
- 2018
16. Plasma glutamine and glutamic acid are potential biomarkers for predicting diabetic retinopathy
- Author
-
Ki-Young Kim, Jeong Taek Woo, Sang Youl Rhee, Su Jin Jeong, Eun Sung Jung, Hye Min Park, Choong Hwan Lee, Suk Chon, and Seung-Young Yu
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Glutamine ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,030209 endocrinology & metabolism ,Biochemistry ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,Metabolomics ,Diabetes complications ,Diabetic retinopathy ,Diabetes mellitus ,Internal medicine ,medicine ,Receiver operating characteristic ,business.industry ,Diabetes mellitus, type 2 ,Glutamic acid ,medicine.disease ,030104 developmental biology ,Cohort ,Original Article ,business ,Complication - Abstract
Introduction Diabetic patients with a long disease duration usually accompanied complication such as diabetic retinopathy, but in some patients had no complication. Objectives We analyzed differences in plasma metabolites according to the presence or absence of diabetic retinopathy (DR) in type 2 diabetic (T2D) patients with disease duration ≥ 15 years. Methods A cohort of 183 T2D patients was established. Their biospecimens and clinical information were collected in accordance with the guidelines of the National Biobank of Korea, and the Korean Diabetes Association. DR phenotypes of the subjects were verified by ophthalmologic specialists. Plasma metabolites were analyzed using gas chromatography time-of-flight mass spectrometry and ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry. And these results were analyzed using multivariate statistics. Results For metabolomic study, propensity score matched case and control subjects were chosen. Mean age of the subjects was 66.4 years and mean T2D duration was 22.2 years. Metabolomic identification revealed various carbohydrates, amino acids, and organic compounds that distinguished between age- and sex-matched non-diabetic controls and T2D subjects. Among these, glutamine and glutamic acid were suggested as the most distinctive metabolites for the presence of DR. Receiver operating characteristics curves showed an excellent diagnostic value of combined (AUC = 0.739) and the ratio (AUC = 0.742) of glutamine and glutamic acid for DR. And these results were consistent in validation analyses. Conclusion Our results imply that plasma glutamine, glutamic acid, and their ratio may be valuable as novel biomarkers for anticipating DR in T2D subjects. Electronic supplementary material The online version of this article (10.1007/s11306-018-1383-3) contains supplementary material, which is available to authorized users.
- Published
- 2018
17. Attogram mass sensing based on silicon microbeam resonators
- Author
-
Han Young Yu, Jin-Hwa Ryu, Won Ik Jang, In-Bok Baek, Seongjae Lee, Bong Kuk Lee, Sangwon Byun, Yarkyeon Kim, and Yong Sun Yoon
- Subjects
Microelectromechanical systems ,Multidisciplinary ,Materials science ,Silicon ,business.industry ,Surface stress ,010401 analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,Microbeam ,021001 nanoscience & nanotechnology ,01 natural sciences ,Article ,0104 chemical sciences ,Resonator ,chemistry.chemical_compound ,chemistry ,Silicon nitride ,Optoelectronics ,Thin film ,0210 nano-technology ,business ,Beam (structure) - Abstract
Using doubly-clamped silicon (Si) microbeam resonators, we demonstrate sub-attogram per Hertz (ag/Hz) mass sensitivity, which is extremely high sensitivity achieved by micro-scale MEMS mass sensors. We also characterize unusual buckling phenomena of the resonators. The thin-film based resonator is composed of a Si microbeam surrounded by silicon nitride (SiN) anchors, which significantly improve performance by providing fixation on the microbeam and stabilizing oscillating motion. Here, we introduce two fabrication techniques to further improve the mass sensitivity. First, we minimize surface stress by depositing a sacrificial SiN layer, which prevents damage on the Si microbeam. Second, we modify anchor structure to find optimal design that allows the microbeam to oscillate in quasi-one dimensional mode while achieving high quality factor. Mass loading is conducted by depositing Au/Ti thin films on the local area of the microbeam surface. Using sequential mass loading, we test effects of changing beam dimensions, position of mass loading, and distribution of a metal film on the mass sensitivity. In addition, we demonstrate that microbeams suffer local micro-buckling and global buckling by excessive mass loading, which are induced by two different mechanisms. We also find that the critical buckling length is increased by additional support from the anchors.
- Published
- 2017
18. Fan and Tsai: Intracommunity Variation in Plant-Based Food Consumption at the Market Street Chinatown, San Jose, California
- Author
-
Linda Scott Cummings, Chad Yost, Kathryn Puseman, Ryan Kennedy, Peter Kováčik, Barbara L. Voss, Connie Young Yu, and Megan S. Kane
- Subjects
Consumption (economics) ,Gerontology ,Archeology ,History ,060102 archaeology ,Range (biology) ,Chinatown ,media_common.quotation_subject ,05 social sciences ,Immigration ,Food consumption ,Foodways ,Plant based ,06 humanities and the arts ,Geography ,Variation (linguistics) ,0502 economics and business ,0601 history and archaeology ,Socioeconomics ,050212 sport, leisure & tourism ,media_common - Abstract
Most archaeobotanical research on Chinese immigrant communities in North America has relied on aggregate, site-wide data sets. The question of foodways variability within Chinese immigrant communities has been relatively neglected. An intrasite comparative approach is used here to investigate differences in plant-food consumption between residents of merchant households and those of tenement buildings in the Market Street Chinatown, a major urban Chinese immigrant community in San Jose, California, from 1866 to 1887. Residents of both household types consumed a nutritious diet rich in vegetables and fresh fruits; however, some merchant households consumed greater varieties of cereal grains, while residents of some working-class tenements consumed a wider range of legumes, vegetables, fruits, and nuts. These class-based differences were not consistent, however, suggesting that specific occupation, more than class position, may have influenced access to or preference for certain plant foods.
- Published
- 2014
19. Amylase and cysteine proteinase gene knockdown in rice cells using RNA interference for enhancing production of recombinant proteins
- Author
-
Nan-Sun Kim, Hwa-Young Yu, Seon-Hui Jang, Nguyen-Duc Chung, Tae-Ho Kwon, Tae-Geum Kim, and Moon-Sik Yang
- Subjects
Gel electrophoresis ,Gene knockdown ,Protease ,medicine.diagnostic_test ,medicine.medical_treatment ,Transgene ,food and beverages ,Horticulture ,Biology ,Molecular biology ,Genetically modified rice ,Biochemistry ,Western blot ,Cell culture ,RNA interference ,medicine - Abstract
A rice cell suspension culture with the rice α-amylase 3D promoter expression system which is induced by sucrose starvation was previously reported to generate a good yield of recombinant proteins. However, this expression system is limited by the accumulation of undesirable α-amylase and proteases in the culture medium. Rice α-amylase is a dominant protein at 43 % of total secreted proteins, and cysteine proteinase (CysP) is a major secreted protease in rice cell suspension cultures following induction via sugar depletion. Here, we nearly eliminated rice α-amylase and CysP proteinase via RNA interference (RNAi) technology to improve the recombinant protein yield in rice cell suspension culture. The effects of RNAi were characterized by sodium dodecyl sulfate–polyacrylamide gel electrophoresis, Western blot analysis with anti-CysP antibody, and quantitative real-time reverse transcription polymerase chain reaction analysis (RT-PCR). The mRNA levels of α-amylase and CysP were reduced by 94.8 and 95.0 %, respectively. Transgenic rice cell suspension cultures expressing both human granulocyte–macrophage colony-stimulating factor (hGM-CSF) and ihpRNA of α-amylase and CysP genes evidenced a reduction of α-amylase and CysP activity and up to 2.4-fold improvement of hGM-CSF production compared to that in a transgenic cell line expressing hGM-CSF only. Our rice cell suspension culture for the reduction of α-amylase accumulation and protease activity in the culture medium could improve recombinant protein production as an efficient protein expression system using RNA interference technology in plant biotechnology.
- Published
- 2013
20. Overview of the KoRIA Facility for Rare Isotope Beams
- Author
-
Seonho Choi, Kwang Souk Sim, Joon Kon Kim, Kyong Sei Lee, Byoung Jin Suh, Young Kwan Kwon, Sunghyun Kim, Won Namkung, In Sik Hahn, W. Kim, Byung Yoon Park, Claudio Tenreiro, Chang Ill Choi, Eunah Joo, Y. Blumenfeld, Jerry Nolen, Young Ku Yang, Do Yoon Kim, Kang Seog Lee, Yongseok Oh, Kie Hyung Chung, Dong Uk Kim, Jong Won Kim, Myung-Ki Cheoun, Eunjoo Kim, Jaeho Jang, Tae Sun Park, Yeon Suk Choi, Byung-Sik Hong, Sang Hoon Hwang, Doh Yun Jang, Hee Jeong Seo, Woon Young So, Byung Gu Cheon, Byung Geel Yu, Hyo Jung Choi, Sun Chan Jeong, Woo-Yoon Park, Zhou Tong, Chun Sik Lee, Gi Dong Kim, Aram Kim, Hae Ryong Yang, Yeong Heum Yeon, Yong Sub Cho, Jong Tae Kim, Seung il Nam, V. K. Manchanda, Jin Ah Park, Jae Min Han, EunMi Choi, Seung Kook Ko, Hyung Ju Woo, Myeun Kwon, Chong Cheoul Yun, Jong Seo Chai, Yong Yung Lee, H. S. Lee, Jang Min Han, Ho Seung Song, Seung-wook Shin, Hee Jung Lee, Yacine Kadi, Sun Young Ryu, Won Ju Yi, Seung-Woo Hong, Chang Ho Hyun, Ju Hahn Lee, Sang-Hoon Kim, Chang-Hwan Lee, Ki Hyeon Park, P. Sigg, Chung Yeol Ryu, Jung Keun Ahn, Byoung Hwi Kang, Se Hwan Park, Su Houng Lee, Hee Seock Lee, Jang Ho Ha, Yasushige Yano, Donghyun Cho, Kang Ok Lee, Dai Hyuk Yu, Byoung Noh Lee, Bo Young Lee, Young Sung Lee, Min Sik Choi, Tae Keun Choi, Seon Young Yu, Wan Hong, Sang Duk Lee, Hideyuki Sakai, Seok Kwan Lee, Sang-Ho Kim, Bong Hyuk Choi, Chang Bum Moon, G. Jhang, Min Sang Ryu, Dong-O Jeon, Jae Won Shin, Yong Kyun Kim, Robert E. Tribble, In Kwon Yoo, Hyun-Chul Kim, Hoon Su Kang, Doo Jeong, Byung Hoon Oh, Jin Yong Park, Sang In Bak, Cheol Woo Lee, Jin Hwan Oh, Tae Yung Song, Dong Lak Kim, In Gyu Kim, Eun Ja Ha, Young Ouk Lee, Institut de Physique Nucléaire d'Orsay (IPNO), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
- Subjects
Physics ,Isotope ,010308 nuclear & particles physics ,Cyclotron ,chemistry.chemical_element ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,Uranium ,7. Clean energy ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Linear particle accelerator ,law.invention ,Nuclear physics ,chemistry ,law ,0103 physical sciences ,010306 general physics - Abstract
See paper for full list of authors; The Korea Rare Isotope Accelerator, currently referred to as KoRIA, is briefly presented. The KoRIA facility is aimed to enable cutting-edge sciences in a wide range of fields. It consists of a 70 kW isotope separator on-line (ISOL) facility driven by a 70 MeV, 1 mA proton cyclotron and a 400 kW in-flight fragmentation (IFF) facility. The ISOL facility uses a superconducting (SC) linac for post-acceleration of rare isotopes up to about 18 MeV/u, while the SC linac of IFF facility is capable of accelerating uranium beams up to 200 MeV/u, 8 pμA and proton beams up to 600 MeV, 660 μA. Overall features of the KoRIA facility are presented with a focus on the accelerator design.
- Published
- 2012
21. Nuclear Corrections in ν A DIS and Their Compatibility with Global NPDF Analyses
- Author
-
Ji-Young Yu, Jorge G. Morfin, F. I. Olness, I. Schienbein, K. Kovařík, J. F. Owens, T. Stavreva, C. E. Keppel, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Physics ,Particle physics ,010308 nuclear & particles physics ,High Energy Physics::Phenomenology ,Nuclear Theory ,Parton ,Deep inelastic scattering ,01 natural sciences ,Nuclear environment ,Atomic and Molecular Physics, and Optics ,Nuclear physics ,Distribution function ,[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph] ,0103 physical sciences ,Individual data ,High Energy Physics::Experiment ,Nuclear Experiment ,010306 general physics ,ComputingMilieux_MISCELLANEOUS ,Charged current - Abstract
We perform a global χ 2-analysis of nuclear parton distribution functions using data from charged current neutrino–nucleus (ν A) deep inelastic scattering (DIS), charged-lepton–nucleus (l ± A) DIS, and the Drell–Yan (DY) process. We show that the nuclear corrections in ν A DIS are not compatible with the predictions derived from l ± A DIS and DY data. We quantify this result using a hypothesis-testing criterion based on the χ 2 distribution which we apply to the total χ 2 as well as to the χ 2 of the individual data sets. We find that it is not possible to accommodate the data from ν A and l ± A DIS by an acceptable combined fit. This implies that either the twist-2 parton distribution functions in nuclei are not universal, or that higher-twist terms play a more important role in the nuclear environment and have to be taken into account.
- Published
- 2012
22. Combinatorial engineering of ldh-a and bcl-2 for reducing lactate production and improving cell growth in dihydrofolate reductase-deficient Chinese hamster ovary cells
- Author
-
Min Kyoung Jeon, Gyun Min Lee, and Da Young Yu
- Subjects
Cell Survival ,Recombinant Fusion Proteins ,Gene Expression ,Apoptosis ,CHO Cells ,Applied Microbiology and Biotechnology ,Cricetulus ,Downregulation and upregulation ,Cricetinae ,Dihydrofolate reductase ,Animals ,Lactic Acid ,chemistry.chemical_classification ,L-Lactate Dehydrogenase ,biology ,Cell growth ,Chinese hamster ovary cell ,General Medicine ,Metabolism ,Immunoglobulin Fc Fragments ,Isoenzymes ,Tetrahydrofolate Dehydrogenase ,Enzyme ,Proto-Oncogene Proteins c-bcl-2 ,Biochemistry ,chemistry ,Cell culture ,biology.protein ,Lactate Dehydrogenase 5 ,Oxidation-Reduction ,Biotechnology - Abstract
In Chinese hamster ovary (CHO) cells, rapid glucose metabolism normally leads to inefficient use of glucose, most of which is converted to lactate during cell cultures. Since lactate accumulation during the culture often exerts a negative effect on cell growth and valuable product formation, several genetic engineering approaches have been developed to suppress lactate dehydrogenase-A (LDH-A), the enzyme converting pyruvate into lactate. However, despite the reduced lactate accumulation, such cell cultures are eventually terminated in the late period of the culture, mainly due to apoptosis. Therefore, we developed an apoptosis-resistant, less lactate-producing dhfr(-) CHO cell line (CHO-Bcl2-LDHAsi) by overexpressing Bcl-2, one of the most well-known anti-apoptotic proteins, and by downregulating LDH-A in a dhfr(-) CHO cell line. When the dhfr(-) CHO-Bcl2-LDHAsi cell line was used as a host cell line for the development of recombinant CHO (rCHO) cells producing an Fc-fusion protein, the culture longevity of the rCHO cells was extended without any detrimental effect of genetic engineering on specific protein productivity. Simultaneously, the specific lactate production rate and apparent yield of lactate from glucose were reduced to 21-65% and 37-78% of the control cells, respectively. Taken together, these results show that the use of an apoptosis-resistant, less lactate-producing dhfr(-) CHO cell line as a host cell line saves the time and the effort of establishing an apoptosis-resistant, less lactate-producing rCHO cells for producing therapeutic proteins.
- Published
- 2011
23. Controlled Synthesis of Monolayer Graphene Toward Transparent Flexible Conductive Film Application
- Author
-
Han-Young Yu, Goo-Hwan Jeong, and Byeong-Joo Lee
- Subjects
Materials science ,Hydrogen ,Nanochemistry ,chemistry.chemical_element ,Nanotechnology ,Chemical vapor deposition ,law.invention ,chemistry.chemical_compound ,Materials Science(all) ,law ,lcsh:TA401-492 ,Polyethylene terephthalate ,General Materials Science ,Wafer ,Thin film ,Chemistry/Food Science, general ,Transparent conducting film ,Nano Express ,Material Science ,Graphene ,Engineering, General ,Materials Science, general ,Conductive film ,Condensed Matter Physics ,Transfer ,Physics, General ,chemistry ,Chemical engineering ,Transparent ,Raman spectroscopy ,Molecular Medicine ,lcsh:Materials of engineering and construction. Mechanics of materials ,Flexible - Abstract
We demonstrate the synthesis of monolayer graphene using thermal chemical vapor deposition and successive transfer onto arbitrary substrates toward transparent flexible conductive film application. We used electron-beam-deposited Ni thin film as a synthetic catalyst and introduced a gas mixture consisting of methane and hydrogen. To optimize the synthesis condition, we investigated the effects of synthetic temperature and cooling rate in the ranges of 850–1,000°C and 2–8°C/min, respectively. It was found that a cooling rate of 4°C/min after 1,000°C synthesis is the most effective condition for monolayer graphene production. We also successfully transferred as-synthesized graphene films to arbitrary substrates such as silicon-dioxide-coated wafers, glass, and polyethylene terephthalate sheets to develop transparent, flexible, and conductive film application.
- Published
- 2010
24. The Synergistic Effect of Tautomycetin on Cyclosporine A-Mediated Immunosuppression in a Rodent Islet Allograft Model
- Author
-
Jin Hee Kim, Seung Young Yu, Monica Young Choi, Sang Kyou Lee, Yang-Hee Kim, Duck Jong Han, Yu Mee Wee, Choong Hoon Kang, and Song Cheol Kim
- Subjects
Graft Rejection ,Male ,Cell Survival ,medicine.medical_treatment ,Lymphocyte ,Islets of Langerhans Transplantation ,Pharmacology ,Biology ,Diabetes Mellitus, Experimental ,Rats, Sprague-Dawley ,Islets of Langerhans ,Transplantation Immunology ,Genetics ,medicine ,Splenocyte ,Animals ,Transplantation, Homologous ,Lymphocytes ,Viability assay ,Furans ,Pancreas ,Molecular Biology ,Genetics (clinical) ,Cell Proliferation ,geography ,geography.geographical_feature_category ,Interleukin ,FOXP3 ,Drug Synergism ,Forkhead Transcription Factors ,Islet ,Immunohistochemistry ,Lipids ,Interleukin-10 ,Rats ,Transplantation ,Disease Models, Animal ,medicine.anatomical_structure ,Liver ,Rats, Inbred Lew ,Immunology ,Cyclosporine ,Molecular Medicine ,Female ,Immunosuppressive Agents ,Spleen ,Research Article ,Allotransplantation - Abstract
Most immunosuppressive drugs that support successful allograft survival act by inhibiting or depleting T lymphocytes. Tautomycetin (TMC) is a specific inhibitor of protein phosphatase 1, which has a role in cell-cycle control and T-cell activation and promotes T-cell–specific apoptosis. In this study, we investigated the effect on rat islet transplantation of TMC alone and in combination with cyclosporine A (CsA). TMC treatment inhibited splenocyte proliferation in mixed lymphocyte reactions (MLR) without affecting cell viability. When used alone in islet allograft recipients, TMC did not significantly increase the survival of grafted islets. However, cotreatment of TMC and subtherapeutic doses of CsA significantly prolonged islet graft survival from 5.1 d to more than 100 d (P < 0.05). At 100 d, there was no evidence of specific organ toxicity, and histological analyses of grafted liver tissue revealed the presence of viable islets. CD4+ and CD8+ T-cell infiltration and interleukin (IL)-2 mRNA levels were decreased in TMC/CsA-cotreated rats, whereas IL-10 levels were increased. In addition, the number of FoxP3-expressing cells and FoxP3 mRNA levels were also increased. We suggest that CsA and TMC act synergistically to reduce the function of T-effector cells and enhance regulatory cell function in this islet allotransplantation model.
- Published
- 2010
25. Characteristics and link structure of a national scholarly Web space: The case of South Korea
- Author
-
Yong Kwang Kim, Suyeon Kim, Young Mee Chung, and So-Young Yu
- Subjects
Structure (mathematical logic) ,Sociology of scientific knowledge ,Government ,General Social Sciences ,Directory ,Library and Information Sciences ,Data science ,Scholarly communication ,Backlink ,Computer Science Applications ,World Wide Web ,Geography ,Ranking ,Metric (mathematics) - Abstract
This study performs a webometric analysis to explore the communication characteristics of scientific knowledge in a national scholarly Web space comprising top ranking universities and government supported research institutions in South Korea. We found significant differences in scholarly communication activity as well as linking behavior among different subspaces in addition to institutional differences. We also found the usefulness of the ADM approach in analyzing the metric data containing extreme outliers and discovered the directory model as the most appropriate. Page counts were found significantly correlated with inlinks as well as with outlinks at the directory level in the whole scholarly Web space.
- Published
- 2009
26. On Tracking Hua Kiu: A Chinese American Historian’s View
- Author
-
Connie Young Yu
- Subjects
Archeology ,History ,Art history ,Tracking (education) ,Chinese americans - Published
- 2008
27. Sulfur and oxygen isotopic compositions of the dissolved sulphate in the meteoric water in Chuncheon, Korea
- Author
-
Jae-Young Yu, Randall E. Mielke, Youngyun Park, and Max Coleman
- Subjects
Pollutant ,Global meteoric water line ,business.industry ,chemistry.chemical_element ,Oxygen ,Sulfur ,chemistry.chemical_compound ,chemistry ,Environmental chemistry ,Meteoric water ,Kinetic fractionation ,General Earth and Planetary Sciences ,Coal ,Sulfate ,business ,General Environmental Science - Abstract
The meteoric water deposited in the Chuncheon area was collected from July 2002 to May 2004 and its chemical and isotopic compositions were analyzed to examine if the isotopic data can help trace the sources of the sulfur pollutant and understand the details of acid formation processes in the air. The chemical compositions of the meteoric water indicate that the sulfate mostly comes from anthropogenic sources. The sulfur isotopic compositions of the dissolved sulfate in the meteoric water (δ34Sso4) vary from 2.6 to 7.5‰ with little seasonal differences, which are significantly different from those of the sulfur in the coal being locally consumed (−4.5 to −0.7‰). This difference indicates that the local coal consumption gives insignificant contribution to the pollutant sulfur in the acid deposition of the area. The relationship between (δ34Sso4) and the concentration of sulfate suggests that the sources of pollutant sulfur are variable and inhomogeneous. The oxygen isotopic compositions of the dissolved sulfate in the meteoric water (δ18O4) range from 9.0 to 17.2‰ which are generally lower in winter than in spring. Comparison between the measured and calculated values of (δ18Oso4) suggests that the oxygen isotopic exchange between sulfite and water occurs before its oxidation to sulfate. The extent of isotopic exchange seems to be not controlled by equilibrium but by kinetic fractionation. The poor correlation between δ34S4) and the oxygen isotopic composition of the meteoric water confinns the disequilibrium nature of the isotopic exchange.
- Published
- 2007
28. On the intrinsic bottom content of the nucleon and its impact on heavy new physics at the LHC
- Author
-
Florian Lyonnet, Fred Olness, K. Kovarik, Aleksander Kusina, ans Ji-Young Yu, Ingo Schienbein, T. Jezo, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), and LHC
- Subjects
Physics ,Quark ,Quantum chromodynamics ,Nuclear and High Energy Physics ,Particle physics ,010308 nuclear & particles physics ,Physics beyond the Standard Model ,High Energy Physics::Phenomenology ,Degrees of freedom (physics and chemistry) ,FOS: Physical sciences ,Parton ,01 natural sciences ,Bottom quark ,Nuclear physics ,High Energy Physics - Phenomenology ,High Energy Physics - Phenomenology (hep-ph) ,[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph] ,0103 physical sciences ,High Energy Physics::Experiment ,Charm (quantum number) ,Nuclear Experiment ,010306 general physics ,Nucleon - Abstract
Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon splitting and do not involve any non-perturbative degrees of freedom. It is clearly necessary to test this hypothesis with suitable QCD processes. Conversely, a non-perturbative, intrinsic heavy quark parton distribution has been predicted in the literature. We demonstrate that to a very good approximation the scale-evolution of the intrinsic heavy quark content of the nucleon is governed by non-singlet evolution equations. This allows us to analyze the intrinsic heavy quark distributions without having to resort to a full-fledged global analysis of parton distribution functions. We exploit this freedom to model intrinsic bottom distributions which are so far missing in the literature in order to estimate the impact of this non-perturbative contribution to the bottom-quark PDF, and on parton--parton luminosities at the LHC. This technique can be applied to the case of intrinsic charm, albeit within the limitations outlined in the following., 23 pages, 11 figures
- Published
- 2015
29. Adsorption of phenol and chlorophenols on hexadecyltrimethylammonium-and tetramethylammonium-montmorillonite from aqueous solutions
- Author
-
Jung-Ju Seo, Jin-Hwan Noh, Mi-Young Shin, and Jae-Young Yu
- Subjects
Tetramethylammonium ,Order of reaction ,Aqueous solution ,Inorganic chemistry ,Langmuir adsorption model ,symbols.namesake ,chemistry.chemical_compound ,Adsorption ,chemistry ,Bentonite ,symbols ,General Earth and Planetary Sciences ,Phenol ,Freundlich equation ,General Environmental Science - Abstract
Batch experiments were carried out at 25°C to obtain the adsorption isotherms of phenol, 2-cholorophenol, 4-chlorophenol and 2,4-dichlorophenol on hexadecyltrimethylammonium-exchanged-and tetramethylammonium-exchanged-montmorillonite (HDTMA-M and TMA-M) prepared from Wyoming bentonite SWy-2. The isotherms were interpreted principally using the Freundlich model. The reaction orders (n) and Freundlich constants (k F) for the adsorption of an adsorbate on HDTMA-M and TMA-M remain approximately constant against the variation of adsorbate to adsorbent ratios. Then value for most of the phenolic adsorbates on HDTMA-M is close to unity, indicating Langmuir-type adsorption but that on TMA-M is variable among different phenolic adsorbates. The degree of adsorption of phenolic compounds on HDTMA-M is primarily controlled by the hydrophobicity of the adsorbates but those on TMA governed by the complicated combinations of size, shape and hydrophobicities of the adsorbates. The estimated model parameters for the adsorption isotherms on HDTMA-M are in disagreement with those of earlier workers probably because of the differences in experimental conditions. This study also estimated the model parameters on TMA-M, which are not available in the literature.
- Published
- 2004
30. Adsorption of phenol and chlorophenols on Ca-montmorillonite in aqueous solutions
- Author
-
Mi-Young Shin, Jung-Ju Seo, Jin-Hwan Noh, and Jae-Young Yu
- Subjects
Chlorophenol ,chemistry.chemical_compound ,Adsorption ,Montmorillonite ,Aqueous solution ,chemistry ,Freundlich model ,Inorganic chemistry ,General Earth and Planetary Sciences ,Phenol ,Freundlich equation ,Dichlorophenol ,General Environmental Science - Abstract
Adsorption of phenol, 2-chlorophenol, and 2,4-dichlorophenol on Ca-montmorillonite was studied with batch experiments at 25°C. The results from the experiments show that the amount of the adsorption of the phenolic compounds increases with chlorination, i.e., phenol
- Published
- 2004
31. Theoretical calculation of Gibbs free energy of mixing of biotite: phlogopite-annite-eastonite-siderophyllite system
- Author
-
Jae-Young Yu
- Subjects
Spinodal ,Materials science ,Annite ,Thermodynamics ,Ideal solution ,Entropy of mixing ,engineering.material ,Siderophyllite ,engineering ,General Earth and Planetary Sciences ,Phlogopite ,Solvus ,Biotite ,General Environmental Science - Abstract
The Gibbs free energy of mixing (ΔG mix ) can be represented as the sum of the ideal mixing energy (ΔG id ) and the excess energy (G ex ). For biotite in phlogopite (Ph)-annite (An)-eastonite (Es)-siderophyllite (Sd) system, ΔG id is estimated based on MOS (mixing on site) model andG ex is obtained from the theoretically calculated binding energies of biotite. Previous experimental works suggested that Ph-An and possibly Ph-Es pairs form ideal solutions. In this study, however,G ex shows that none of the binary solutions among Ph-An-Es-Sd end-members are ideal. The calculated ΔG mix indicates that Ph-An and Es-Sd pairs form complete solutions, but Ph-Es and An-Sd pairs both mixed by Tschermak's substitution show miscibility gaps. The limit of Tschermak's substitution in biotite is a function of the mole fraction of Fe in the trioctahedral site,X(Fe), and temperature. A comparison of the solvus and spinodal points obtained from the calculated ΔG mix with the chemical compositions of the synthesized and natural biotites implies that Es and Sd are metastable and the limits of Tschermak's substitution are determined not by solvus curves but by spinodal ones. Most chemical compositions of natural biotite fall fairly well within the range defined by the estimated spinodal curves at 800°C, although there are some out-lying biotites especially when theirX(Fe) is between 0.5 and 0.7. The general good agreement in limits of Tschermak's substitution between what natural biotite shows and what this study predicts suggests that the theoretical function of thermodynamic mixing of this study seems promising to be applied for understanding the behavior of not only biotite but also other similar solid solutions, particulary when experimental approach is difficult.
- Published
- 1997
32. The fabrication technique and electrical properties of a free-standing GaN nanowire
- Author
-
Ung Hwan Pi, Han Young Yu, Cheol Jin Lee, Sung-Yool Choi, Byung Hyun Kang, and Chan Woo Park
- Subjects
Fabrication ,Materials science ,business.industry ,Schottky barrier ,Nanogenerator ,Nanowire ,General Chemistry ,Substrate (electronics) ,Atmospheric temperature range ,Etching (microfabrication) ,Optoelectronics ,General Materials Science ,Reactive-ion etching ,business - Abstract
We fabricated a free-standing structure of a GaN nanowire by selectively etching Si3N4, previously grown on a SiO2 substrate, for application to three-dimensional integrated circuits such as nanorelays and actuators. In the nanowire-deposition process we adopted electrophoresis and reactive ion etching techniques to achieve a well-aligned and free-standing nanowire. The electrical transport measurements were performed from room temperature down to liquid-nitrogen temperature. The current–voltage (I–V) characteristics showed a rectifying behavior in the whole temperature range. We analyze this property as a Schottky barrier formation between the nanowire and electrodes.
- Published
- 2005
33. Dual modality intravascular imaging of unstable, symptomatic but 'hemodynamically insignificant' carotid stenosis
- Author
-
Martin K.C. Ng, Young Yu, Harry C. Lowe, G. Michael Halmagyi, and Belinda Gray
- Subjects
medicine.medical_specialty ,Stenosis ,Neurology ,business.industry ,medicine ,Dual modality ,Neurology (clinical) ,Radiology ,medicine.disease ,business ,Intravascular imaging ,Neuroradiology - Published
- 2013
34. Precipitation of Fe and Al compounds from the acid mine waters in the dogyae area, Korea: A qualitative measure of equilibrium modeling applicability and neutralization capacity?
- Author
-
Jae-Young Yu
- Subjects
Chemistry ,Precipitation (chemistry) ,Aqueous two-phase system ,Mineralogy ,engineering.material ,Ferrihydrite ,Geophysics ,Geochemistry and Petrology ,Phase (matter) ,engineering ,Pyrite ,Compositional data ,Gibbsite ,Chemical composition - Abstract
To investigate the applicability of equilibrium modeling for the estimation of the chemical changes of acid mine waters, the phases predicted to precipitate by equilibrium calculation were compared with what actually precipitates from the stream and acid mine waters in the Dogyae area, Korea. The computer program MINTEQA2 was used for the equilibrium calculations based on the chemical compositional data of the water samples collected in the study area. XRD, IR, thermal and chemical analyses of the collected precipitates were performed to identify their phases. The results of the identification of the collected precipitates are inconsistent with what the equilibrium calculations predict. The equilibrium calculations indicate that ferrihydrite, FeOHSO4, gibbsite, and AlOHSO4 should precipitate from the stream and acid mine waters in the study area. However, the experimental analyses show that only ferrihydrite and Al4(OH)10SO4 are the recognizable precipitates on the bottom of the stream and mine drainage channels. Comparing the stability relations among the possible precipitates with the field occurrence of the precipitates in the study area suggests that FeOHSO4 and AIOHSO4 are kinetically inhibited to precipitate and metastable ferrihydrite and Al4(OH)10SO4 appear in their stability field instead. It indicates that the chemical compositional change of the waters due to the solid phase precipitation in the study area must be interpreted and predicted in terms of the precipitation of not the phases predicted by the equilibrium calculation but the actually identified ones. Assuming that the dissolved species in the aqueous phase are in equilibrium with respect to the currently precipitating solid phases in the study area, the water chemistries are attempted to interpret based on the plot of the theoretically calculated activities of the dissolved species on the stability diagram for the identified precipitates and gibbsite. The plot reveals a few evolution paths of the chemical composition of the acid mine water as the acid generation and neutralization progress. The evolution path producing ferrihydrite and then Al4(OH)10SO4 precipitation suggests that the system including acid producing pyrite has lost significant amounts of its neutralizing capacity and thus, become intolerable to the impacts from acid mine water.
- Published
- 1996
35. [Untitled]
- Author
-
Sung gun Ko, Joon Shin, In Kwon Chung, Toshiyuki Tanaka, Eun Young Yu, and Weon Tae Lee
- Subjects
Telomere-binding protein ,Genetics ,Oryza sativa ,biology ,Chemistry ,Domain (ring theory) ,Resonance ,Oryza ,biology.organism_classification ,Biochemistry ,Spectroscopy ,Telomere binding ,Telomere - Published
- 2003
36. Erratum to: The Synergistic Effect of Tautomycetin on Cyclosporine A-Mediated Immunosuppression in a Rodent Islet Allograft Model
- Author
-
Yu-Mee Wee, Monica Young Choi, Choong-Hoon Kang, Yang-Hee Kim, Jin-Hee Kim, Sang-Kyou Lee, Seung-Young Yu, Song-Cheol Kim, and Duck-Jong Han
- Subjects
Genetics ,Molecular Medicine ,Molecular Biology ,Genetics (clinical) - Published
- 2012
37. A proposed OB-fold with a protein-interaction surface in Candida albicans telomerase protein Est3
- Author
-
Young Yu, Eun, primary, Wang, Feng, additional, Lei, Ming, additional, and Lue, Neal F, additional
- Published
- 2008
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.