• Applied Biological Chemistry
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• v.37 no.2
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• pp.100-104
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• 1994

From the 48 hour-cultured mycelial broth of Phellinus linteus, six compounds were isolated by means of ethyl acetate extraction, silica gel column chromatography and preparative thin layer chromatography, consecutively. Compound 1 was identified as a succinic acid by the comparison of its spectral data with authentic sample. Compounds 2 and 3 were identified as p-hydroxyphenyl acetic acid methyl ester and p-hydroxybenzaldehyde by spectroscopic studies, respectively. NMR and MS studies of compound 6 revealed that it was 2,5-dihydroxymethyl furan. Compound 4, which showed similar NMR absorptions and MS fragmentation pattern with those of compound 6 was identified as 2-hydroxymethyl-5-methoxymethylfuran. These structures were verified by the spectral data of the acetate derivatives of the compounds. Compound 5 was supposed to be a N-acetyltyramine from its $^1H-NMR$ and EI-MS data, and its structure was confirmed by a synthesis starting from tyramine.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.12 s.354
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• pp.55-64
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• 2006

This work proposes a calibration-free 14b 70MS/s 0.13um CMOS ADC for high-performance integrated systems such as WLAN and high-definition video systems simultaneously requiring high resolution, low power, and small size at high speed. The proposed ADC employs signal insensitive 3-D fully symmetric layout techniques in two MDACs for high matching accuracy without any calibration. A three-stage pipeline architecture minimizes power consumption and chip area at the target resolution and sampling rate. The input SHA with a controlled trans-conductance ratio of two amplifier stages simultaneously achieves high gain and high phase margin with gate-bootstrapped sampling switches for 14b input accuracy at the Nyquist frequency. A back-end sub-ranging flash ADC with open-loop offset cancellation and interpolation achieves 6b accuracy at 70MS/s. Low-noise current and voltage references are employed on chip with optional off-chip reference voltages. The prototype ADC implemented in a 0.13um CMOS is based on a 0.35um minimum channel length for 2.5V applications. The measured DNL and INL are within 0.65LSB and l.80LSB, respectively. The prototype ADC shows maximum SNDR and SFDR of 66dB and 81dB and a power consumption of 235mW at 70MS/s. The active die area is $3.3mm^2$.

• Physical Therapy Korea
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• v.29 no.4
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• pp.255-261
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• 2022

Background: For the elderly, masticatory function is one of the most important oral functions and the masticatory ability is related to the wearing of dentures. Many older people wear dentures for their masticatory function, but a significant number of older people who use dentures have found that they feel uncomfortable when performing their daily activities, such as performing masticating functions or talking. Objects: The purpose of this study is to investigate how the forward head posture (FHP), respiratory function and thickness of masseter (MS), and sternocleidomastoid (SCM) are affected by the presence or absence of dentures in the elderly, and what kind of correlation there is between these variables. Methods: The study was conducted on 11 patients in the normal group and 13 in the denture group. The participant's cognitive ability was evaluated using Mini-Mental State Examination Korean (MMSE-K), and the FHP was evaluated by measuring the craniovertebral angle (CVA). The thickness of the MS and SCM muscles were measured using ultrasound, and respiration was measured with a spirometry. As for the statistical method, the correlation of each variable was investigated using Spearman's correlation coefficient. Results: In the normal group, there was a significant correlation between forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) (p < 0.001), and in the denture group, FVC and FEV1 (p < 0.001), maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) (p < 0.001), CVA and Lt. MS (p = 0.012). Conclusion: CVA and Lt. MS of the denture group have a high negative correlation, it is related that the thickness of MS may be thick when the elderly wearing dentures are FHP.

• Journal of IKEEE
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• v.23 no.1
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• pp.35-43
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• 2019

A capacitor self-calibration is proposed to improve the linearity of the capacitor digital-to-analog converter (CDAC) for an asynchronous successive approximation register (SAR) analog-to-digital converter (ADC) with 10-bit resolution. The proposed capacitor self-calibration is performed so that the value of each capacitor of the upper 5 bits of the 10-bit CDAC is equal to the sum of the values of the lower capacitors. According to the behavioral simulation results, the proposed capacitor self-calibration improves the performances of differential nonlinearity (DNL) and integral nonlinearity (INL) from -0.810/+0.194 LSBs and -0.832/+0.832 LSBs to -0.235/+0.178 LSBs and -0.227/+0.227 LSBs, respectively, when the maximum capacitor mismatch of the CDAC is 4%. The proposed 10-bit 20-MS/s asynchronous SAR ADC is implemented using a 110-nm CMOS process with supply of 1.2 V. The area and power consumption of the proposed asynchronous SAR ADC are $0.205mm^2$ and 1.25 mW, respectively. The proposed asynchronous SAR ADC with the capacitor calibration has a effective number of bits (ENOBs) of 9.194 bits at a sampling rate of 20 MS/s about a $2.4-V_{PP}$ differential analog input with a frequency of 96.13 kHz.

• Journal of Life Science
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• v.29 no.1
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• pp.90-96
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• 2019

The objective of this study was to evaluate the potential of Diospyros malabarica stem extract, a natural materials, in oral health material. With this aim in mind, thin layer chromatography (TLC), TLC-bioautography, high-performance liquid chromatography (HPLC), electrospray ionization-mass spectrometry (ESI-MS), scanning electron microscopy (SEM), and real-time qPCR were performed. The antibacterial activity of D. malabarica stem extract against Streptococcus mutans KCTC3065 was confirmed in an n-hexane fraction with low polarity. The molecular weight of the antibacterial compound was estimated to be 188 by ESI-MS analysis. The inhibitory effects of the extract on biofilm formation and gene expression related to biofilm formation of S. mutans were determined by SEM and real-time PCR analysis. The extract inhibited the formation of S. mutans biofilms at D. malabarica stem extract concentrations of 1 mg/ml, as shown by SEM. The real-time PCR analysis showed that the expression of the gtfC gene, which is associated with biofilm formation, was significantly decreased in a dose-dependent manner. Based on the above results, it can be concluded that D. malabarica stem extracts, a natural materials, can be used in oral health products to suppress the formation of biofilms by inhibiting tooth adhesion of S. mutans, a causative agent of dental caries.

• Economic and Environmental Geology
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• v.48 no.4
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• pp.301-312
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• 2015

A commercial gas field was found in the southwestern continental shelf of the Ulleung Basin, East Sea in the late 1990s. To develop additional gas field, an exploration well was drilled through the coarse infill of submarine canyon near the gas field, but it was uneconomic to develop hydrocarbons. Using newly acquired deep seismic reflection and previous well data, we have identified additional geological structure which has hydrocarbon potentials below submarine canyons in the southwestern margin of the basin. Based on the interpretation of the deep seismic reflection and well data, the sequences of the study area can be classified into the syn-rift megasequence(MS1), post-rift megasequence(MS2), syn-compressional megasequence(MS3), and post-compressional megasequence(MS4) in relation to the tectonic events. MS1, deposited simultaneously with the basin formation before the middle Miocene, is characterized by chaotic seismic facies with low- to moderate-amplitude and low frequency reflections. MS2 comprises laterally continuous, low- to moderate-amplitude reflections, showing progradational stacking patterns due to high rates of sediment supply during basin expansion in the middle Miocene. MS3 is mainly composed of continuous reflections with high amplitude and moderate- to high-frequency which are interpreted as coarse-grained sediments. The coarse-grained sediments of MS3 sequence is widely truncated by several submarine canyons which filled with fine-grained sediment of MS4 to form a stratigraphic trap of hydrocarbon. Therefore, the reservoir and seal of the hydrocarbon trap in the study area are coarse-grained sediment of MS3 and submarine canyon filled with fine-grained sediment of MS4, respectively. A flat-spot seismic anomaly, which may indicate the presence of hydrocarbon, is observed within the stratigraphic trap.

• Journal of Genetic Medicine
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• v.4 no.1
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• pp.45-52
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• 2007

Purpose : A simple, rapid, and highly sensitive analytical method for Gb3 in plasma was developed without labor-ex tensive pre-treatment by electrospray ionization MS/ MS (ESI-MS/MS). Measurement of globotriaosy lceramide (Gb3, ceramide trihex oside) in plasma has clinical importance for monitoring after enzyme replacement therapy in Fabry disease patients. The disease is an X-linked lipid storage disorder that results from a deficiency of the enzyme ${\alpha}$-galactosidase A (${\alpha}$-Gal A). The lack of ${\alpha}$-Gal A causes an intracellular accumulation of glycosphingolipids, mainly Gb3. Methods : Only simple 50-fold dilution of plasma is necessary for the extraction and isolation of Gb3 in plasma. Gb3 in diluted plasma was dissolved in dioxane containing C17:0 Gb3 as an internal standard. After centrifugation it was directly injected and analyzed through guard column by in combination with multiple reaction monitoring mode of ESI-MS/MS. Results : Eight isoforms of Gb3 were completely resolved from plasma matrix. C16:0 Gb3 occupied 50% of total Gb3 as a major component in plasma. Linear relationship for Gb3 isoforms w as found in the range of 0.001-1.0 ${\mu}g$/mL. The limit of detection (S/N=3) was 0.001 ${\mu}g$/mL and limit of quantification was 0.01 ${\mu}g$/mL for C16:0 Gb3 with acceptable precision and accuracy. Correlation coefficient of calibration curves for 8 Gb3 isoforms ranged from 0.9678 to 0.9982. Conclusion : This quantitative method developed could be useful for rapid and sensitive 1st line Fabry disease screening, monitoring and/or diagnostic tool for Fabry disease.

• Journal of Chest Surgery
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• v.49 no.5
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• pp.350-355
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• 2016

Background: Mitral stenosis (MS) remains one of the important heart diseases. There are many factors that influence the clinical outcomes, and little is known about how left ventricular (LV) dysfunction clinically affects the prognosis of the patient with MS after mitral valve replacement (MVR). We reviewed our clinical experiences of MVR in patients with MS who had LV dysfunction. Methods: Between January 1991 and January 2013, 110 patients with MS who underwent MVR were analyzed and divided into two groups according to ejection fraction (EF). Group 1 ($EF{\leq}45%$) included 13 patients and group 2 (EF>45%) included 97 patients. Results: Thromboembolism occurred in 8 patients after MVR (group 1: n=3, 23.1%; group 2: n=5, 5.2%) and its incidence was significantly higher in group 1 than in group 2 (p=0.014). There were 3 deaths each in groups 1 and 2 during follow-up. The overall rate of cardiac-related death in group 1 was significantly higher than in group 2 (group 1: n=3, 23.1%; group 2: n=3, 3.1%; p=0.007). The cumulative survival rate at 1 and 15 years was 83.9% and 69.9% in group 1 and 97.9% and 96.3% in group 2 (p=0.004). The Cox regression analysis revealed that survival was significantly associated with postoperative stroke (p=0.011, odds ratio=10.304). Conclusion: This study identified postoperative stroke as an adverse prognostic factor in patients with MS after MVR, and a s more prevalent in patients with LV dysfunction. Postoperative stroke should be reduced to improve clinical outcomes for patients. Preventive care should be made in multiple ways, such as management of LV dysfunction, atrial fibrillation, and anticoagulation.

• Journal of Plant Biotechnology
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• v.29 no.1
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• pp.63-68
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• 2002

The possibility for mass production of phytol, inhibitory diterpene against ACAT (Acyl-CoA: Cholesterol acyltransferase) was investigated by using callus culture of lettuce. The callus were induced from lettuce cotyledon explants on MS medium containing 0.5 mg.L$^{-1}$ NAA after 4 week's culture. Adventitious roots were formed from the explants on MS medium containing 0.5 mg.L$^{-1}$ IBA or 1.0 mg.L$^{-1}$ NAA. Adventitious shoots and roots were emerged from the callus when the callus was transferred to MS medium containing auxin alone, or with cytokinin. The plant growth regulators and their concentrations for the organogenesis were 1.0 mg.L$^{-1}$ NAA, 0.1 mg.L$^{-1}$ BA, 0.5 mg.L$^{-1}$ NAA with 0.1 mg.L$^{-1}$ kinetin, or 0.5 g.L$^{-1}$ 2.4-D with 1.0 mg.L$^{-1}$ kinetin. Analyses of chlorophyll contents showed that chlorophyll contents were higher in morphogenic calli than in non-morphogenic calli. However, the chemical analyses of gas chromatography indicated that phytol contents were not proportionate to the chlorophyll contents of callus. The content of phytol was higher in callus than in lettuce cotyledon.ledon.

• Korean Journal of Medicinal Crop Science
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• v.13 no.1
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• pp.57-62
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• 2005

Salt-tolerant transgenic Panax ginseng plants were produced by introducing the SAL1 geue (3'(2'), 5'-bis-phosphate nucleotidase) that confers tolerance to the salts through Agrobacterium tumefaciens co-cultivation. Cotyledon explants of immature ginseng zygotic embryos cultured on Murashige and Skoog medium lacking growth regulators formed somatic embryos directly with below 10%, but the 74% tranformation rate were observed at the treatment of phytohormone with 1.0 mg/l 2,4-D and 0.5 mg/l kinetin. Somatic embryos were initially cultured on MS medium supplemented with 250 mg/l cefotaxime for 3 weeks and subsequently subcultured five times to a medium containing 100 mg/l kanamycin and 250 mg/l cefotaxime. Upon development into the cotyledonary stage, these somatic embryos were transferred to on the medium containing 50 mg/l kanamycin and 10 mg/l gibberellic acid to induce germination and strong selection. Integration of the transgene into the plants was confirmed by polymerase chain reaction with specific primers. The ginseng transformants with well-developed shoots and roots were successfully acclimatized in a greenhouse when they were planted in soil.