• Research in Plant Disease
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• v.10 no.1
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• pp.63-68
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• 2004

Twenty-three strains of Serratia sp., isolated from surface-sterilized rice roots collected in Chonbuk and Chungnam province, were identified and characterized. They were Gram-negative, rod shaped and red pigmented typically and their endophytism was confirmed by inoculation and reisolation of the strains in planta. Their antifungal activity against 4 rice pathogenic fungi was compared and ranged from 62.4 to 85.2％ against Rhizoctonia solani and 68.0 to 88.5％ against Pyricularia grisea. Among the 23 strains tested, strain Rsm220 showed the strongest inhibition activity against 4 pathogenic fungi. The strain was, therefore, selected as a biocontrol candidate for both the pathogens and its bacteriological characteristics and 165 rDNA sequences were analyzed. Phenotypic and biochemical characteristics of the selected Rsm220 were highly related to the type strain of S. marcescens and 165 rDNA sequencing of Rsm220 showed a homology of 98.2％ to the type strain of S. marcescens. The strain Rsm220 was identified as S. marcescens and the inhibition result of this endophytic strain indicates that it is a potential biocontrol agent for R. solani and R grisea.

• YAKHAK HOEJI
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• v.41 no.2
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• pp.225-232
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• 1997

The in vitro antibacterial activity of DWP20367 (1-Cyclopropyl-6-fluoro-8-chloro-7-(2,7-diazabicyclo[3,3,0]oct-4-ene-7-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid), a new broad-spectrum fluoroquinolone, was compared with those of ciprofloxacin (CPFX), sparfloxacin (SPFX) and ofloxacin (OFLX). DWP20367 was showed antibacterial activity much higher than CPFX, SPFX and OFLK against gram-positive bacteria, while it was slightly more superior to quinolones against gram-negative bacteria. DWP20367 was particularly effective against MRSA, and its $MlC_{90}$ against clinical isolates of methicillin-susceptible S. aureus, low methicillin-resistant S. aureus and high methicillin-resistant S. aureus were 0.098, 0.781 and 1.563 micro g/ml, respectively. Against S. pneumoniae, MIC90 of DWP20367 was 2- to 8-fold higher than those of CPFX. With a view of MIC90, DWP20367 showed slightly more potent activity against P. aeruginosa and E. coli isolates than the control quinolones. DWP20367 activity was not affected by inoculum size and medium pH. But addition of $Mg^{2+}, \;Ca^{2+} $Mg2+, Ca2+ or horse serum (25%) decreased its antibacterial activity. DWP20367 was showed rapidly bactericidal activity within 2 to 4 h, and regrowth was not observed even after 24 h incubation at concentrations near the 4-fold of MIC.

• Journal of Environmental Impact Assessment
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• v.21 no.6
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• pp.841-857
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• 2012

Preliminary ecological environmental assessments including physico-chemical constituents, water quality, fish fauna analysis, physical habitat health, and ecological health assessment were conducted as a primary step for Jeungchon micro-habitat ecosystem restoration in 2012. Water chemistry analysis of conductivity, dissolved oxygen, chlorophyll-a and etc. indicated that there were no significant differences(p < 0.05) among 6 sites between the headwaters and downstream. Multi-metric model analysis of Qualitative Habitat Evaluation Index(QHEI) showed that brooklets were at "good condition" as a mean QHEI of 158.7(n = 6) and the longitudinal differences of the model values between the sites were minor(QHEI range: 153 - 165). Total fish species and the number of individuals were 12 and 481, respectively, and dominant species were Zacco platypus(49.5%) and Zacco koreanus(36.8%). Tolerance guild analysis showed that the proportion of sensitive species($S_S$) had a negative linear function[$S_S=86.35-0.31(D_H)$; $R^2$ = 0.892, p < 0.01] with a distance from the headwaters, while the proportion of tolerant species($T_S$) had a positive linear function($R^2$ = 0.950, F = 90.28, p < 0.001) with the distance. Trophic feeding guild analysis showed that the proportion of insectivore species($I_n$) had a negative linear function($R^2$ = 0.934, p < 0.01) with a distance from the headwaters, while the proportion of omnivore species($O_m$) had a positive linear function($R^2$ = 0.958, p < 0.001) with the distance. Index of Biological Integrity(IBI) model, based on fish assemblages, showed a "fair condition" as a mean IBI of 23(n = 6), and there was a distinct differences of ecological health between the headwaters(S1 = 30; "good condition") and the downstreams(S6 = 14; "poor condition"). Overall, the preliminary environmental impact assessments suggest that water quality, physical habitat conditions(QHEI model), and ecological health(IBI model) were maintained well, even if the state was not an excellent conditions.

• Journal of Periodontal and Implant Science
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• v.28 no.4
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• pp.691-703
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• 1998

The 16S rRNA analyzing method is a bacterial identification method that is useful in identifying bacteria which is difficult to do by other means. The following 7 types of bacteria which are Treponema, A. actinomycetemcomitans, P. gingivalis, Fusobacterium, B. forsythus, P. intermedia, P. micros were evaluated in order to study their distribution among patients with adult periodontitis. The 16S rRNA analyzing method was used to compare bacterial distribution among 3 groups. Subgingival plaque acquired from the affected sites(pocket depth ${\geq}6mm$) of 29 patients with adult periodontitis were grouped as the experimental group while plaque from the non-affected sites(pocket depth ${\leq}3mm$) were grouped as control 2 and finally plaque acquired from students with healthy periodontal tissues were grouped as control 1. The results are as follows ; 1. The distribution of Treponema was 12.5% for control 1, 21.4% for control 2 and 75.4% for the experimental group. For A. actinomycetemcomitans the distribution was 0.5%, 19.0%, 44.4% in respect to the order of groups mentioned above. P.gingivalis showed 10.5%, 43.1%, 94.0% distribution, Fusobacterium 33.0%, 48.3%, 81.0% distribution, B. forsythus 9.5%, 17.2%, 65.9% distribution, P. intermedia 1.0%, 12.1%, 26.3% distribution and finally P. micros 5.0%, 19.0%, 48.7% respectively. In all 7 types of bacteria, the experimental group showed higher bacterial distribution compared to the other two groups with statistically significant difference. 2. In the case of Treponema, A. actinomycetemcomitans, gingivalis,Fusobacterium, B. forsythus, P. intermedia, P. micros showed significant difference between control 1 and 2. These results suggest that the 16S rRNA analyzing method which was applied on Koreans for the first time could be utilized and useful in finding potential pathogens of periodontal disease.

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.243-248
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• 2004

Production of (R)-3-hydroxybutyric acid (R3HB) by fed-batch culture and continuous culture of metabolically engineered Escherichia coli harboring Ralstonia eutropha PHB biosynthesis and depolymerase genes was examined in a 30 1 pilot-scale fermentor. A new stable two-plasmid system, pBRRed containing the R. eutropha PHB depolymerase gene and pMCS 105 containing the R. eutropha PHB biosynthesis genes, was developed. Among a variety of E. coli strains harboring plasmids, recombinant E. coli XL-10 Gold (pBRRed, pMCS105) was able to produce R3HB with the highest efficiency in a batch culture. By the fed-batch culture of recombinant E. coli XL-10 Gold(pBRRed, pMCS 105) in a 30 1 fer-mentor, the final R3HB concentration was 22.4 g/l giving a productivity of 0.97 g/l-h. To produce R3HB to a high concentration with high productivity, a new strategy of fed-batch culture followed by a continuous culture was investigated. The maximum productivity and R3HB concentration were 5.06 g/l-h and 25.3 g/l, respectively. These results show that economical production of R3HB is possible by recombinant E. coli in large scale.

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.157-167
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• 2021

This study is a descriptive research study to find out the relationship between degree of Self-Esteem, Anger-Out, Anger-In, Anger-Control and SNS Addiction Tendency of high school students, and the factors that influence SNS addiction tendency. For a total of 10 days from May 18 to 28, 2020, a total of 100 people were collected using online questionnaires to those who were attending high schools in S and G regions and using SNS. As a result of the study, SNS addiction tendency and self-esteem(r=.385, p<.001), anger-control(r=-.354, p<.001) showed a normal inverse correlation, and an anger-out (r=.321, p=.001), anger-in (r=308, p=.002) showed a common net correlation. Factors affecting SNS addiction tendencies were self-esteem(β=-.297, p=.001), gender(β=.266, p=.003), and anger-out(β=.247, p=.007), with 27.7% explanatory power in the regression model(F=12.279, p<.001). Therefore, it is necessary to develop programs to increase high school students' self-esteem and lower their anger-out in order to reduce SNS addiction tendencies, especially for female high school students in gender.

• 한국체육학회지인문사회과학편
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• v.55 no.3
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• pp.543-551
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• 2016

The study was aimed at investigating the relationship between biomechanical properties of cervical muscles and smartphone addiction score in fifty healthy males using smartphone more than 60 minutes each day. The usage of smartphone was evaluated by smartphone addiction survey developed from Korean International Society Agency. Biomechanical properties of three major cervical muscles; splenius capitis, sternocleidomastoid and upper trapezius, were measured by Myoton, and conducted five parameters; frequency, decrement, stiffness, creep, and relaxation time. As results, all parameters had less than 2% of coefficient of variation(CV) between measurement intervals. Also, intra-class correlation coefficient(ICC) indicated a high reliability(ICC>.9, p<.01). Moreover, the smartphone addiction score was significantly different in frequency(r=.353, p<.05) and stiffness(r=.346, p<.05) on upper trapezius; in addition, in decrement(r=-.284, p<.05) and creep(r=.288, p<.05) on sternocleidomastoid. Especially, splenius capitis was closely related with the overuse of smartphone(frequency, r=-.368, p<.01; decrement, r=-.405, p<.01; stiffness, r=-.424, p<.01). In conclusion, this study implied that the overuse of smartphone is significantly related with the damage of cervical muscles, cervical pain, and headache; furthermore, Myoton can be used as an effective device to assess mechanical properties of cervical muscles.

• Korean Journal of Community Nutrition
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• v.7 no.3
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• pp.327-335
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• 2002

This study was performed to investigate the relationships among bone mineral densities (BMD), anthropometric data and lifestyle factors in the elderly. Subjects included 138 elderly (male: 38, female: 100) aged over 65 years, who were home-(dwelling in a low-income area of Puchon City. The BMDs of the lumbar spines (LS), femoral necks (FN), Ward′s triangles (WT) and trochanters (TC) were measured by dual energy X-ray absorptiometry. The females showed significantly lower BMDs in four sites (p < 0.0001) . The elderly aged over 75 revealed significantly more decreased femoral BMDs than the elderly aged 65 to 74. Female with BMIs of 20 to 25, showed significantly higher BMDs in LS, FN and trochanter than those with BMIs of less than 20. However, males displayed significantly higher BMDs in only LS with increasing BMIs. THe BMDs of LS correlated with weights (r = 0.543, p < 0.001), heights (r = 0.477, p < 0.001), upper arm circumferences (r=0.368, p < 0.01), waist circumferences (r=0.367, p < 0.001), subscapular skinfold thicknesses (r=0.363, p < 0.001) and flip circumferences (r=0.231, p < 0.01). Non-smokers and non-drinkers shelved significantly higher BMDs in trochanters only in the case of the males. Female milk-drinkers showed significantly elevated LS BMDs. Eighteen percent of the males were assessed as having osteoporosis, as compared to fifty percent of the females. Ninety-three percent of the females and 81.6% of the males responded that they often or always had "difficulty in standing for a long time".

• Korean Journal of Mathematics
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• v.23 no.1
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• pp.129-151
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• 2015

In this paper, we prove an $L^p$ version of Donoho-Stark's uncertainty principle for the inverse of the hypergeometric Fourier transform on $\mathbb{R}^d$. Next, using the ultracontractive properties of the semigroups generated by the Heckman-Opdam Laplacian operator, we obtain an $L^p$ Heisenberg-Pauli-Weyl uncertainty principle for the inverse of the hypergeometric Fourier transform on $\mathbb{R}^d$.

• Child Health Nursing Research
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• v.9 no.2
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• pp.198-205
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• 2003

Purpose: The purpose of this study is to investigate the degree of school children's internet addiction and to explicit the relationship among the internet addiction, family environment and school adjustment. Method: The subjects of the study were 640 students from 5th and 6th year children of five elementary schools in G city. The data were analyzed by SAS program with frequency, percentage, means, standard deviation, χ² -test, ANOVA and Pearson's Correlation Coefficient. Result: In the degree of the internet addiction were 10.0％ of addiction group, 58.0％ of intermediate group, and 32.0％ of nonaddiction group. There were significant differences in family environment score(F=25.09, p=.0001) and school adjustment score(F=34.46, p=.0001) regarding internet addiction degree. The relationship among internet addiction score, family environment score and school adjustment score revealed a significant inverse correlation(r=-0.32, p=.0001, r=-0.35, p=.0001). And the relationship between family environment score and school adjustment score revealed a significant correlation(r=0.52, p=.0001). Conclusion: The degree of school children's internet addiction has been found to be very high and correlated to the family environment and school adjustment. Therefore, programs should be developed in order to improve this situation.