• Journal of Periodontal and Implant Science
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• v.24 no.3
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• pp.529-540
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• 1994

Rapidly progressive periodontitis is known to be usually associated with systemic problems and improved with antibiotic therapy. Recent experiments in which bioresorbable polycaprolactone was polymerized with minocycline has shown that the system released effective antibiotic concentration during the 7 days' period. This clinical trial was to compare the efficacy of a minocycline film(poly-caprolactone+polyglycol+10% minocycline) insertion plus supragingival scaling(MS) or subgingival scaling & root planing(MSRP) with the scaling(S) or subgingival scaling & root planing alone(SRP), at improving the periodontal condition in RPP. Fifteen patients were examined for plaque accumulation, gingival inflammation, probing depth and attachment loss at baseline, then 1, 2, 4 and 8 weeks after 4 treatment regimens were randomly undergone in 4 comparable sites(PD>5mm, LA>3mm) in each subject. Results revealed statistically significant treatement effect with a reduction in a probing depth in SRP(2.0mm), MS(1.8mm), and MSRP(2.1mm). There was no significant reduction in the supragingival scaling alone group(0.6mm). Similarly, attachment levels were significantly improved in the SRP(1.5mm), MS(2.0mm) and MSRP(2.0mm) groups. Net % BOP reduction at 8 week compared to baseline was 6.7% (S), 26.7% (MS), 26.7% (SRP), and 33.3% (MSRP). MSRP produced the greatest improvement in BOP at 8 week. This data suggests that a subgingival minocycline delivery system as a adjunct to scaling alone or scaling & root planing may produce significant clinical benefits over scaling alone in rapidly progressive periodontitis patients.

• Mass Spectrometry Letters
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• v.2 no.1
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• pp.1-7
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• 2011

China's rapid economic growth has resulted in significant environmental side effects. Therefore, China has been interested in reducing her dependence on foreign oil and gas by developing technologies needed for hydrogen, in addition to her increasing energy mix of nuclear and renewable energy form, such as solar and wind power. There are three isotopes of hydrogen, i.e. protium (P or H), deuterium (D), and tritium (T). Both deuterium and tritium are important materials in nuclear fuel cycle industry. Tritium is one of the critical radioactive nuclides. Planning for and implementing contamination control as a part of normal operation and maintenance activities is an important function in any hydrogen facility, especially tritium facility. The development of hydrogen isotopes analysis is the key issues in this area. Mass spectrometry (MS) with medium (about 600) and high resolution (> 1,400) is commercially available; however, the routine analysis of hydrogen isotopes is done with low-resolution MS (< 200) in China. This paper summarizes the progress of MS measurement technology for hydrogen isotope abundance in China, focusing on our lab's research program and technical status. An analyzing method has been introduced for accurate measurement of tritium abundance in the H.D.T system by low resolution MAT-253 MS. The quotient of compression ratio coefficient is determined by building up equipment for laboratory-scale preparation of secondary standard gases and by considering the difference in sensitivity between hydrogen isotopes. The results show that the measured value is reproducible within the relative error range of 0.8% for gas samples of different tritium abundance.

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.161-168
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• 2004

Optimal regeneration conditions of ginseng transformants were studied. It has been known that Ferritin Light Heavy Chain (FLHC) gene remove the several heavy metal by combination, store and transport. To obtain the ginseng tolerant to heavy metal, binary vector was introduced in Agrobacterium by tri-parental mating and then Agrobacterium tumefaciens MP90/FLHC was selected on the AB media and MS media containing kanamycin. Explants were co-cultured with Agrobacterium tumefaciens MP90/FLHC, which contained NPT II as a selectable marker, tadpole ferritin heavy chain (FLHC) gene and human ferritin light chain gene and then a number of embryos were induced. The induced embryo transferred to shooting media consisting of MS medium supplemented with GA 10 mg/L. As a result of examination that induced the normal growth of transfomants, transformants showed the equivalent growth in both root and shoot on the media containing the 1/3 MS.

• Journal of Life Science
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• v.9 no.1
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• pp.29-34
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• 1999

Cotyledon and hypocotyl explants of perilla were cultured on MS medium containing a combined concentration of BA(0.5, 1.0 and 1.5mg/$\ell$) and NAA(0.1, 0.5 and 2.0mg/$\ell$) in order to regenerate the explant and induce the callus. The best regeneration of the explant and induction of the callus were observed in a combined concenteration of 0.5mg/$\ell$ of BA and 0.5mg/$\ell$ NAA both in cotyledon and hypocotyl explants. In cotyledon explants, rooting was achieved upon transferring shoots to MS medium containing 0.5mg/$\ell$ of BA and 0.1mg/$\ell$ of NAA. We also investigated the change of protein and RNA content on developmental stage of callus and plant regeneration of perilla. Protein content was increased but RNA content was decreased as the culture period increases. The banding pattern of polypeptide revealed that both 30KD and 45KD polypeptides were obvious in cotyledon obtained from pre-culture explants, but only 30KD polypeptide was further getting obvious as the culture period increases.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.5
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• pp.67-74
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• 2013

A low-power 12-bit resistor string DAC for wireless sensor applications is presented. Two-step approach reduces complexity, minimizes power consumption and area, and increases speed. This chip is fabricated in 0.18-${\mu}m$ CMOS and the die area is $0.76mm{\times}0.56mm$. The measured power consumption is 1.8mW from the supply voltage of 1.8V. Measured SFDR(Spurious-Free Dynamic Range) is 70dB when the sampling frequency is less than 1 MHz.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.9
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• pp.1227-1232
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• 2008

Carcass characteristics data of Hanwoo (N = 1,084) were collected from two stations of the National Livestock Institute of Animal Science (NIAS), Korea and records from thirteen individual cow-calf operators were analyzed to estimate variance and covariance components and the effect of different slaughter endpoints. Carcass traits analyzed were cold carcass weight (CWT, kg), REA (rib eye area, cm2), back fat thickness (mm) and marbling score (1-7). Four different models were examined. All models included sex and contemporary group as fixed effects and the animal's direct genetic potential and environment as random effects. The first model fitted a linear covariate of age at slaughter. The second model fitted both linear and quadratic covariates of age at slaughter. The third model fitted a linear covariate of body weight at slaughter. The fourth model fitted both linear covariates of age at slaughter and body weight at slaughter. Variance components were estimated using the REML procedure with Gibb's sampler. Heritability estimate of CWT was in the range of 0.08-0.11 depending on the model applied. Heritability estimates of BF, REA and MS were in the ranges of 0.23-0.28, 0.19-0.26, and 0.44-0.45, respectively. Genetic correlations between CWT and BF, between CWT and REA, and between CWT and MS were in the ranges of -0.33 - -0.14, 0.73-0.84, and -0.01- 0.11, respectively. Genetic correlations between REA and BF, between MS and BF and between REA and MS were in the ranges of -0.82 ~ -0.72, 0.04~0.28 and -0.08 ~ -0.02, respectively. Variance and covariance components estimated varied by model with different slaughter endpoints. Body weight endpoint was more effective for direct selection in favor of yield traits and body weight endpoints affected more of the correlated response to selection for the traits of yield and quality of edible portion of beef.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.97-101
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• 2001

The transport and allocation of photosynthetic assimilate is an important regulatory factor in plant productivity, In order to modify assimilate partitioning in rice, transgenic plants containing a potato sucrose transporter (SuT) gene were developed. Calli derived from rice seeds (Oryza sativa L. cv Dongjin) were cocultured with A. tumefaciens LBA 4404 harboring the SuT gene. Calli were transferred to MS medium supplemented with 50 mg/L hygromycin, 500 mg/L carbenicillin, 2 mg/L kinetin, 0.1 mg/L NAA. After 2 weeks, hygromycin resistant shoots were obtained from the calli on the selection medium. Roots were induced from the putative transgenic shoots on rooting MS medium supplemented with 250 mg/L cabenicillin. Plant regeneration rate from the calli was about 150%. Stable incorporation of the potato SuT gene into rice genomic DNA was confirmed by PCR and Southern blot analysis.

• Journal of Yeungnam Medical Science
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• v.31 no.2
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• pp.94-98
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• 2014

Background: We analyzed the changes in QT dispersion (QTd) in children with Kawasaki disease (KD), and determined the presence of repolarization abnormality in these children even in the absence of coronary artery abnormalities. Methods: Ninety-one children with KD and 20 healthy controls were enrolled in this retrospective study. Serial echocardiographic and electrocardiographic (ECG) measurements in the beginning of treatment, 2nd month and 6th month after the diagnosis were compared. Fifty-one of 91 children had at least 2 serial ECG data. The number of patients who had 3 consecutive ECG data was 23. Results: Among the 67 KD patients with no coronary artery changes, the consecutive mean QTd values were 41.86 ms, 37.84 ms, and 25.47 ms, respectively (26 ms for controls). In the analysis of changes among KD patients without coronary artery abnormalities, QTd showed a significant decrease with time (p=0.01). Especially, the 1st month and the 6th month QTd values were significantly different (p=0.028). The mean QTd values in KD patients with coronary artery changes were significantly higher than those in KD patients with no coronary artery changes at each time (1st, 2nd, and 6th month exam). Conclusion: QTd is significantly increased in children during the early stage of KD. Repolarization abnormality may exist during the acute stage of KD, regardless of the echocardiographic changes.

• Journal of Environmental Health Sciences
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• v.48 no.1
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• pp.36-43
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• 2022

Background: Preservatives are used to prevent product deterioration in modeling clay. Parabens, a representative preservative, have been found to be endocrine disruptors and cause skin irritation and allergic reactions. Isothiazolinone preservatives can be irritating to the skin, respiratory tract, and eyes. Thorough investigation and regulation of clay are necessary because clay is marketed to children, who are more sensitive to the toxic effect of chemicals. Objectives: In this study, the presence of 16 preservatives was analyzed in modeling clay and the results were compared with current standards. Methods: A total of 200 samples were collected from 28 children's clay products sold in South Korea (13 from Korea and 15 imported from overseas). Twelve preservatives, such as parabens, were analyzed using high-performance liquid chromatography (HPLC). Isothiazolinone preservatives (chloromethylisothiazolinone; CMIT, methylisothiazolinone; MIT, octylisothiazolinone; OIT, and benzisothiazolinone; BIT) were analyzed using ultra performance liquid chromatography-tandem mass spectrometery (UPLC-MS/MS). Results: Dehydroacetic acid (DHA) was detected the most in the clays at 51.50% (103 cases) detection; 38 cases (median 190.42 ㎍/g) in Korean products and 65 cases (median 169.62 ㎍/g) in Chinese products. CMIT, which is prohibited in Korea, was detected in 14 (median 16.28 ㎍/g) Chinese products. OIT, which has a chemical structure similar to CMIT was found in 28 (median 68.38 ㎍/g) samples in Korean products. Conclusions: The use of CMIT and MIT in children's products is prohibited in Korea and the European Union (EU). The detection of CMIT in Chinese clay products suggests that management is necessary for imported products. It is necessary to review the safety and regulatory status for OIT because OIT was used as a substitute for CMIT and MIT in Korean products.

• Analytical Science and Technology
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• v.24 no.5
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• pp.352-359
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• 2011

An analytical method for solvent-free determination of benzene, toluene, ethylbenzene, and xylenes (BTEX) in water using repetitive membrane extractions coupled to cryofocusing and GC-MS was derived. BTEX compounds that permeated through a nonporous silicone membrane from the aqueous phase and evaporated into the acceptor phase were purged into a cryofocusing trap ($-100^{\circ}C$) with helium gas. The BTEX compounds, thus enriched in the trap, were thermally desorbed into a capillary column GC and detected using an MS. The flow rate of the donor phase (30 mL water) was set at 10 mL/min, and membrane extractions, accomplished by returning the water drained from the extraction module to the sample container, were repeated three times at $20{\pm}2^{\circ}C$. Although recoveries (%) were variable, from the highest for benzene (approximately 80%) to the lowest for ethylbenzene and xylenes (3.5-10%), the method showed satisfactory precision (RSD 2.2-10%) with good-linearity calibration curves ($r^2$ 0.9976-0.9997 in 1-100 ${\mu}g$/L range) for all of the compounds. The method detection limits (MDLs) ranged from 0.16 to 1.8 ${\mu}g$/L. The results showed the method's advantages such as short analysis time and overall simplicity without solvent compared to the conventional techniques.