• Korean Chemical Engineering Research
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• v.49 no.1
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• pp.62-68
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• 2011

In the study, acrylate copolymer as MMA-co-GMA-co-AA with a high hardness and flexibility was synthesized for applying to the clear protection film, where GMA was used as a mediator to enhance polymerization-efficiency between MMA and AA. With an increase of GMA content, molecular weight and hardness of acrylate copolymer increased, however, flexibility decreased. With an increase of AA content, its molecular weight and hardness decreased, however, flexibility increased. Molar ratio of GMA/MMA and AA/GMA were optimized as 1.6 and 1.8, respectively, at 30 g of MMA to enhance hardness and flexibility of acrylate copolymer film. Molecular weight and Tg of the acrylate copoylmer were 13,300 g/mol and 136.5 $^{\circ}C$, respectively. Hardness of the coated film at 1.4 g/$m^2$ of spread was 1 H and no crack was observed at expansion ratio of 5% and 15%, respectively. Hardness of film was improved to 3 H by increasing spread of 4.1-4.6 g/$m^2$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4450-4458
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• 2011

The aim of this study was to investigate the capacity of the xylitol-sensitive(Xs) and xylitol-resistant(Xr) S. mutans to induce dental caries in the presence of various carbohydrate. S. mutans KCTC3065 was cultured with 0.4% glucose and 1% xylitol in TYE medium for 30 days at $37^{\circ}C$, 10% $CO_2$ to form Xr S. mutans. Both Xs and Xr strains were cultured in four different carbohydrate environments; 0.5% glucose containing basal culture TYE medium(G-TYE), G-TYE plus 0.5% sucorse, G-TYE plus 0.5% fructose, G-TYE plus 0.5% maltose. Then cell growth, acid production, and extracellular polysaccharides synthesis were analyzed. The final growth level and extracellular polysaccharides contents in the Xr strain were significantly lower than in the Xs strain in all carbohydrates except fructose. While, acid production was no significantly difference between Xs and Xr strain. These results indicate that the virulence of Xr strains is significantly lower than that of Xs strains, which supports Xr strains may be less cariogenic than Xs strains.

• The Journal of Korean Medicine
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• v.30 no.4
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• pp.129-141
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• 2009

Objective: This study was to investigate the anti-tumor effect, safety, safety, mechanism and metabolizing enzyme of Agrimonia pilosa LEDEB (APL) in female C57B/L mouse tumor (in vivo). Method: First, to evaluate the antitumor activity of APL, we divided the mice into four groups: normal, control, APL50 (50mg/kg), and APL100 (100mg/kg). LLC-obtained American Type Culture Collection was used. LLC had been inoculated to induce tumors. To measure the anti-tumor effect of APL, we calibrated tumor size and weight. To analyze the mechanism of anti-tumor in APL, we used western blotting and to observe metabolizing enzyme in APL we used to real-time PCR. Result: APL50 and APL100 significantly inhibited tumor growth from 12 days after medicine injected. APL did not induce caspase-dependent apoptosis in LLC-bearing mouse tumor. In APL100, it decreased 41% and 71% in CYP2D22 and CYP3A11, respectively. Conclusion: These results suggest that APL has some anti-tumor effects in female C57B/L mouse tumor. APL should be used carefully with other drugs related with CYP2D22 and CYP3A11.

• Journal of Korean society of Dental Hygiene
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• v.14 no.1
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• pp.101-108
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• 2014

Objectives : The purpose of this study was to evaluate the tooth whitening effect of 0.74% and 2.80% hydrogen peroxide toothpastes and safety on tooth and gingival tissue. Methods : Toothpastes containing 0.74% and 2.80% hydrogen peroxide were evaluated. In in-vitro test, some additives (sodium metaphosphate, sodium pyrophosphate and titanium dioxide) were added to the toothpastes. Hydroxyapatite specimens (HAPs) were made and stained using modified Stookey's methods. HAPs were treated for 1 hour at shaking incubator and brushed for 1,000 times as 250 gF with each diluted toothpaste. Before and after color was measured by colorimeter. Using double blind method, 99 Korean with natural maxillary anterior teeth were selected and the initial brightness (baseline) was measured by SHADEEYE-EX. Based on this measurement they were crossly distributed into control group (0% hydrogen peroxide), test 1 (0.74% hydrogen peroxide) and test 2 (2.80% hydrogen peroxide). After 2 weeks, people of each group were provided toothpaste and told to use 3 times a day right after every meal for 3 minutes. The brightness of teeth was measured 3 times for every one month. Results : ${\Delta}L$ was statistically significant among three groups in shaking test. ${\Delta}L$ of two test groups was statistically significant compared with control group but not between each test group in brushing test. After using toothpaste for 3 months, test 1 group and test 2 group were 15.89% and 31.23% more whitened compared with control group respectively (p<0.05). Rate of more whitened person of each test group was 24.2% and 40.5% more than control group respectively (p<0.05). There was no difference in the hypersensitivity during 3 months using toothpastes and no side effect on teeth or gums. Conclusions : Toothpastes containing 0.74% and 2.80% hydrogen peroxide showed tooth whitening effect and both were safe enough to use for tooth whitening.

• Clinical and Experimental Pediatrics
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• v.50 no.3
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• pp.292-297
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• 2007

Purpose : Kawasaki disease (KD) rarely occurs in school-aged children. We clarified the characteristics of KD in this age group to provide tips for a high index of suspicion. Methods : Features of 38 patients with KD who were 7 years of age or older were retrospectively reviewed. Results : The incidence of the KD patients ${\geq}7years$ was 4.9 percent. The ratio of male to female was 2.5:1. Of the 38 patients, nine patients (24.0 percent) were diagnosed with typical KD and 29 patients (76.0 percent) with incomplete KD. In incomplete KD patients, cervical lymphadenopathy (69.0 percent) occurred most frequently, followed by conjunctival injection (62.0 percent) and polymorphous rash (45.0 percent). These patients occasionally presented with other additional symptoms including abdominal pain, headache, vomiting and arthralgia. Incomplete KD was initially diagnosed as cervical lymphadenitis (34.0 percent), viral infection (14.0 percent), scarlet fever (7.0 percent), meningitis (7.0 percent), and Kikuchi disease (7.0 percent). Coronary complications were noted in 15 patients (39.0 percent). Of the 37 patients treated with intravenous immunoglobulin, five (14.0 percent) were resistant to the therapy and all had coronary abnormalities. Conclusion : Most patients with KD ${\geq}7years$ of age have incomplete presentations. They tend to have a higher incidence of initial presentations of unilateral neck mass and coronary artery involvement. In school-aged children, fever and cervical lymphadenitis or suspected neck infection unresponsive to intravenous antibiotics should signal the possibility of KD. A high index of suspicion and prompt treatment is essential in this age group of patients.

• Korean Journal of Applied Biomechanics
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• v.19 no.3
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• pp.457-466
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• 2009

This study puts the purpose in providing the scientific basis of dance motion as an artistic expression by analyzing the kinematic variable and the distribution factor of power affecting the motion, which is connected to the turn, right after the arabesque motion according to the existence and non existence of using the arm in the arabesque motion of modern dance. As a result of this study, arabesque turn motion, not using the upper limbs, used more turning force of head and body than the arabesque turn motion, using the upper limbs, and arabesque turn using the upper limbs obtained the turning force, using the right shoulder. The range of the hip joint on the left and the position change of left tiptoe in the Arabesque turn motion using the upper limbs is largely ascended to the vertical axis, while, the position of tiptoe in the Arabesque turn motion, not using the upper limbs is dropped to the lower part of each event. In the replacement of body center, Arabesque turn motion using the upper limbs is moved more to the turning axis than arabesque turn motion not using the upper limbs. As a result of maximum vertical ground reaction force, Arabesque turn motion using the upper limbs appeared to be a lower value than the Arabesque turn motion not using the upper limbs.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.2
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• pp.178-187
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• 2016

Objectives: Diisocyanates are a potent inducer of diseases of the airways, especially asthma. In this study, toluenediamine(TDA) and methylenedianiline(MDA) in urine were evaluated as biomarkers of exposure to tolunenediisocyanate(TDI) and methylenediphenyl diisocyanate(MDI), respectively. Methods: Workers exposed to TDI and MDI, as well as non-occupationally exposed subjects, were studied and pre- and post-shift urine samples were collected from 8 control subjects and 8 workers from a factory which manufactures polyurethane products for reducing noise and vibration in automobiles. Airborne TDI and MDI(n=8) were sampled on solvent-free glass filters impregnated with n-butylamine and detected by liquid chromatography atmospheric pressure ionization tandem mass spectrometry. Urinary TDA and MDA were detected as pentafluoropropionic acid anhydride(PFPA) derivatives by liquid chromatography electrospray ionization tandem mass spectrometry. Results: The median levels of urinary 2,6-TDA(p<0.001), 2,4-TDA(p=0.001), and MDA(p<0.001) of workers in post-shift samples were significantly higher than those of controls. The median levels of urinary 2,6-0TDA($0.63{\mu}g/g$ creatinine vs $0.34{\mu}g/g$ creatinine, p=0.017) and MDA($4.21{\mu}g/g$ creatinine vs $3.18{\mu}g/g$ creatinine, p=0.017) of workers in post-shift samples were significantly higher than those of the pre-shift samples. There were significant correlations between the urinary 2,6-TDA, 2,4-TDA, and MDA of workers in post-shift samples and the airborne 2,6-TDI(rho=0.952, p<0.001), 2,4-TDI(rho=0.833, p=0.001), and MDI(rho=0.952, p<0.001). Conclusions: These urinary diamines, metabolites of diisocyanates, in post-shift samples were useful biomarkers to assess occupational exposure to diisocyanates.

• The Journal of Internal Korean Medicine
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• v.34 no.3
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• pp.231-239
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• 2013

Objectives : This study was performed to evaluate inter-rater and intra-rater reliability of interpretation and reproducibility of a pulse analyser (MAXMAC27-Plus). Methods : 38 of 40 volunteers completed the pulse analysis consecutively. Three Korean medical doctors who had at least 2 years of clinical experience interpreted the pulse waves for 3 aspects of size, depth and shape, then inter-rater reliability and crude agreement was obtained. Reinterpretation was done 2 weeks later and intra-rater reliability and crude agreement was obtained. Intra-rater reliability and crude agreement between 1st and 2nd measurement was calculated. Cohen's weighted kappa for size, Cohen's kappa for depth and shape were used as statistical analysis. Results : Inter-rater reliability of size, depth and shape among 3 raters was 0.598, 0.604, and 0.312, respectively, showing moderate to substantial agreement. Average intra-rater reliability between 1st and 2nd interpretation of size, depth and shape was 0.806, 0.705, and 0.638, respectively, showing substantial to almost perfect agreement. However, intra-rater reliability between consecutive measurements of size, depth and shape was 0.221, 0.121, and 0.194, respectively, which showed only poor to fair agreement. Conclusions : Intra-rater and inter-rater reliability of one pulse wave showed relatively high concordance. Training by a clinical expert may effect better concordance among raters. Test-retest reliability showed poor agreement. Improvement of measurement technique and device performance will be needed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.36-42
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• 2015

This study was conducted from 2013 to 2014 to explore the feasibility of the cultivation of warm-season grass as an annual Korean forage crop, while concurrently evaluating the characteristics and forage production of warm-season grass in Korea. The experimental design was a randomized block design (RBD) with three replications. Five bermudagrass [Cynodon dactylon (L.) Pers.] cultivars, two teffgrass (Paspalum notatum Flugge) cultivars, and a Kleingrass [Panicum coloratum L.] cultivar were compared for forage production and quality in the middle region of Korea. After seeding, the numbers of days until seedling emergence for bermudagrass and kleingrass were observed at approximately day 11 and day 12, respectively. The heading dates of teffgrass and kleingrass were on July 12 and July 26, respectively. The dry matter (DM) yield of bermudagrass Tifton 85 was usually greater than the other entries. The crude protein content (CPC) and total digestibility nutrient (TDN) for the teffgrass cultivars were usually greater than the other entries at all study sites. The acid detergent fiber (ADF) and in vitro DM digestibility (IVDMD) were similar across all cultivars.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.292-297
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• 2019

In this study, whole crop rice samples were used to develop near-infrared reflectance (NIR) equations to estimate six forage quality parameters: Moisture, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), Ash and relative feed value (RFV). A population of 564 whole crop rice representing a wide range in chemical parameters was used in this study. Undried finely chopped whole crop rice samples were scanned at 1 nm intervals over the wavelength range 680-2500 nm and the optical data recorded as log 1/Reflectance (log 1/R). NIRS calibrations were developed by means of partial least-squares (PLS) regression. The correlation coefficients of cross-validation (R²_cv) and standard error of cross-validation (SECV) for whole crop rice calibration were 0.98 (SECV 1.81%) for moisture, 0.89 (SECV 0.50%) for CP, 0.86 (SECV 1.79%) for NDF, 0.89 (SECV 0.86%) for ash, and 0.84 (SECV 5.21%) for RFV on a dry matter (%), respectively. The NIRS calibration equations developed in this study will be useful in predicting whole crop rice quality for these six quality parameters.