• Journal of Environmental Science International
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• v.28 no.2
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• pp.225-233
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• 2019

In this study, we investigated the in vitro anti-biofilm activities of plant extracts of chives (Allium tuberosum), garlic (Allium sativum), and radish (Raphanus sativus L.) against environment harmful bacteria (gram-positive Staphylococcus aureus and, gram-negative Salmonella typhimurium and Escherichia coli O157:H7). In the paper disc assay, garlic extracts exhibited the highest anti-biofilm activity. The Minimal Inhibitory Concentration (MIC) of all plant extracts was generally higher for gram-negative bacteria than it was for gram-positive bacteria. Gram-negative bacteria were more resistant to plant extracts. The tetrazolium dye (XTT) assay revealed that, each plant extract exhibited a different anti-biofilm activity at the MIC value depending on the pathogen involved. Among the plant extracts tested, garlic extracts (fresh juice and powder) effectively reduced the metabolic activity of the cells of food-poisoning bacteria in biofilms. These anti-biofilm activities were consistent with the results obtained through light microscopic observation. Though the garlic extract reduced biofilm formation for all pathogens tested, to elucidate whether this reduction was due to antimicrobial effects or anti-biofilm effects, we counted the colony forming units of pathogens in the presence of the garlic extract and a control antimicrobial drug. The garlic extract inhibited the E. coli O157:H7 biofilm effectively compared to the control antimicrobial drug ciprofloxacin; however, it did not inhibit S. aureus biofilm significantly compared to ciprofloxacin. In conclusion, garlic extracts could be used as natural food preservatives to prevent the growth of foodborne pathogens and elongater the shelf life of processed foods.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.214-214
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• 2022

Soluble starch synthases (SSs) elongate α-glucans from ADP-Glc to the glucan nonreducing ends and play a critical role in synthesizing resistant starch in the rice. A total of 10 SSs isoforms were reported in rice, including granules-bound starch synthase I (GBSSI), GBSSII, starch synthase I (SSI), SSIIa (SSII-3), SSIIb (SSII-2), SSIIc (SSII-1), SSIIIa (SSIII-2), SSIIIb (SSIII-1), SSIVa (SSIV-1), and SSIVb (SSIV-2). SSIII proteins are involved in forming the B chain and elongating cluster filling chains in amylopectin metabolism. The functions of SSIIIb (SSIII-1) are less clear as compared to SSs. Here, we sought to shed light on the genetic diversity profiling of the SSIII-1 gene in 374 rice accessions composed of 54 wild-type accessions and 320 bred cultivars (temperate japonica, indica, tropical japonica, aus, aromatic, and admixture). In total, 17 haplotypes were identified in the SSIII-1 coding region of 320 bred cultivars, while 44 haplotypes were detected from 54 wild-type accessions. The genetic diversity indices revealed the most negative Tajima's D value in the temperate-japonica, followed by the wild type, while Tajima's D values in other ecotypes were positive, indicating balancing selection. Nucleotide diversity in the SSIII-1 region was highest in the wild group (0.0047) while lowest in temperate-japonica. Lower nucleotide diversity in the temperate-japonica is evidenced by the negative Tajima's D and suggested purifying selection. The fixation index (F_ST) revealed a very high level of gene flow (low F_ST) between the tropical-japonica and admixture groups (F_ST=-0.21) followed by admixture and wild groups (-0.04), indica and admixture groups (0.02), while low gene flow with higher F_ST estimates between the temperate-japonica and aus groups (0.72), tropical-japonica and aromatic groups (0.71), and temperate-japonica and admixture groups (0.52). Taken together, our study offers insights into haplotype diversity and evolutionary fingerprints of SSIII-1. It provides genomic information to increase the resistant starch content of cooked rice.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1728-1733
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• 2006

A Gram-negative, strictly aerobic, nonmotile, and nonspore-forming bacterial strain, designated $T5-12^T$, was isolated from compost and characterized using a polyphasic taxonomical approach. The isolate was positive for catalase and oxidase tests. It could degrade DNA, but was negative for degradation of macromolecules such as casein, collagen, starch, chitin, cellulose, and xylan. The DNA G+C content was 36.0 mol%. The predominant isoprenoid quinone was menaquinone 7 (MK-7). The major fatty acids were $iso-C_{15:0}$ (45.6%), $iso-C_{17:0}$ 3OH (17.2%), and summed feature 4 ($C_{16:0}\;{\omega}7c$ and/or $iso-C_{15:0}$ 2OH, 14.9%). Comparative 16S rRNA gene sequence analysis showed that strain $T5-12^T$ fell within the radiation of the cluster comprising members of the genus Sphingobacterium. Strain $T5-12^T$ exhibited lower than 94% of 16S rRNA gene sequence similarity with respect to the type strains of recognized Sphingobacterium species. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain $T5-12^T$ ($=KCTC\;12578^T=LMG\;23401^T=CCUG\;52467^T$) should be classified in the genus Sphingobacterium as the type strain of a novel species, for which the name Sphingobacterium composti sp. novo is proposed.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1537-1543
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• 2006

A bacterial strain named HY-3 that produces a highly active extracellular protease was isolated from the digestive tract of a spider, Nephila clavata. The bacterium was a Gram-negative, oxidase-negative, catalase-positive, nonhalophilic, nitrate-reducing, facultative anaerobe. Transmission and scanning electron microscopies demonstrated that the isolate was non-spare-forming, straight, rod-shaped, and motile by peritrichous flagella. The G+C content of the DNA was 57.0 mol%. The isoprenoid quinone type was ubiquinone with 8 isoprene units (Q-8). The morphological and biochemical characteristics including the predominant fatty acid and phospholipids profiles placed the isolate HY-3 in the family Enterobacteriaceae. Further biochemical characterization and phylogenetic studies including determination of an almost complete 16S ribosomal DNA sequence suggested that the bacterium was closely related to the genus Serratia. DNA-DNA hybridization analysis revealed that this extracellular protease-producing strain belongs to Serratia proteamaculans, which is also known far its association with insects.

• Journal of the Society of Disaster Information
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• v.11 no.3
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• pp.365-375
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• 2015

This study is significant in the sense that it minimize the negative effect of workplace bullying, ultimately it maximize organizational performance and keep private security guards physical and mental health. We tested the hypothesis that workplace bullying negatively impacts private security guard's office attitude, but there will be significant difference in influence with their level of self-esteem scale. First of all, as the result of the correlation analysis of each of variables, a positive correlation was found between self-esteem and job satisfaction but negative correlation between self-esteem they have, the more job satisfaction they get, the lower turnover intention they have. Second, we tried to find out how self-esteem affect them on their job satisfaction. Using regression analysis, we can see that job satisfaction is affected by age, workplace bullying, relational aggression and self-esteem. For example, job satisfaction is increased as they get old and self-esteem is improved, on the other hand, workplace bullying and relational aggression is decreased. Third, to find out how self-esteem affects their turnover intention, we did regression analysis. The result shows that turnover intention is affected by age, working period, workplace bulling, relational aggression and self-esteem. For example, turnover intention if higher as working period, workplace bullying, relational aggression is increased while age and self-esteem is decreased.

• Restorative Dentistry and Endodontics
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• v.46 no.3
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• pp.35.1-35.11
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• 2021

Objectives: Endosequence Bioceramic Root Repair Material (BC-RRM) is used in endodontic microsurgery. It is available as a paste and a putty. However, no studies to date have examined the sealing ability of these forms alone or in combination as root-end filling materials. Hence, this study aimed to compare the sealing properties of these 2 forms of BC-RRM. Materials and Methods: Forty-two extracted upper anterior teeth were divided into 3 experimental groups, a positive and negative control. After the root canal treatment, the root ends were resected, retroprepared and retrofilled with either putty, paste + putty or mineral trioxide aggregate (MTA). The teeth were mounted in tubes so the apical 3 mm was submerged in Brain Heart Infusion (BHI) broth. The coronal portions of the canals were inoculated with Enterococcus faecalis and BHI broth and incubated for 30 days. The broth in the tubes was analyzed for colony forming units to check for leakage of bacteria from the canal. The teeth from the groups were sectioned and analyzed using scanning electron microscopy (SEM). The Kruskal-Wallis test and analysis of variance were used to analyze the data with a significance level p < 0.05. Results: The BC-RRM and MTA groups showed similar sealing ability. The positive control showed leakage in all samples. The SEM imaging showed the presence of bacteria in all experimental groups at the material-tooth interface. Conclusions: No significant differences were noted in the experimental groups, providing sufficient evidence that any combination could be effectively used during endodontic microsurgery.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.2
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• pp.149-157
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• 2022

The aim of this study was to evaluate the effects of erythrosine-mediated photodynamic therapy (PDT) on Streptococcus mutans biofilm recovery by counting its colony-forming units (CFUs) and via confocal laser scanning microscopy analysis at different time points following PDT. In PDT, photosensitizer was an erythrosine. S. mutans ATCC25175 biofilms were irradiated using an LED curing light. Chlorhexidine (CHX) was used as positive control. After each antimicrobial treatment, samples were cultured to allow biofilm recovery. Viability was measured by calculating the CFU counts after treatment and after every 3 hours for up to 24 hours. Immediately after treatment, the PDT and CHX groups showed equally significant decreases in S. mutans CFU counts compared to the negative control. After 12 hours of reculture, the PDT group showed no significant difference in the decrease in CFU count compared to the negative control, whereas the CHX group showed significantly lower CFU counts throughout the 24-hour period. Erythrosine-mediated PDT can effectively inhibit S. mutans biofilm formation. However, biofilm recovery occurred earlier in the CHX group after PDT. This study provides insights into the clinical effectiveness of PDT in preventing dental caries.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.1
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• pp.107-121
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• 2002

The purpose of this study was to identify how nurse's image was perceived by nursing college students. The subjects included were 315 students experienced clinical practice during $20{\sim}22$ weeks and 134 students not with a total of 449 nursing students in Gwangju and Chonnam. The data were collected from November 21 to December 5, 2001 by the structured questionnaires. The research tool was measured by 30 items divided into four dimensions; traditional, professional, social and personal image of nurse. Cronbach $\alpha$ for the tool of nurse's image was 0.8960. The data were analysed by SPSS 8.0 for Windows program using frequency, percentage, mean, standard deviation, t-test, ANOVA and scheffe. The results of this study were as follows; 1. In the nurse's image related to general characteristics, there were significant differences for school graduation, applicative motivation, interpersonal relationship and image forming factor. 2. In the Image forming factors, nursing college students perceived the nurse's image by visiting hospital or admission(37.9%), watching TV(25.8) and others; nurses' appearance during clinical experience(16.3). 3. The mean score for nurse's image of clinical experience group (2.76$\pm$0.28) was lower than that of non-clinical experience group(2.89$\pm$0.31) in significance (t=4.319, p=0.000). 4. In the nurse's image according to clinical experience, there were significant differences for traditional, professional, social, personal image between two groups and the lower mean scores were found in the clinical experience group in all dimensions. The ranks of dimensions were professional image(3.08), traditional image(2.76), social image(2.65), the personal image(2.59) in clinical experience group, whereas professional image(3.21), traditional image(2.93), social image(2.75), personal image(2.71) for non-clinical experience group.5. The high score items of nurse's image were 'worthwhile work(3.48)', 'always working hard(3.30)', 'profession(3.17)', 'strong responsibility toward work(3.08)', 'have a high technical skill(3.05)' in clinical experience group and 'worthwhile work(3.69)', 'always working hard(3.28)', 'clean and decent(3.22)', 'profession(3.21)', 'have a bountiful professional knowledge(3.18)' in non-clinical experience group. 6. The highest mean score for nurse's image related to the image forming factors was 86.8 by novels or literature and the second highest was 84.3 by visiting hospital or admission. And others(mean=82.1)was the most negative nurse's image by clinical experience. In conclusion, nurse's image perceived by nursing college students will be the mirror of themselves. And clinical experience will be the important opportunity to form the professional image with white uniformed nurses in future. Therefore it is important for clinical nurses to play professional roles rightly so that nursing students could form positive nurse's image.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.1
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• pp.41-47
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• 1988

A laboratory experiment was conducted to find out the abilities of siderophore formation and competition of $Fe^{3+}$ and $Mn^{2+}$ absorption in synthetic medium with inoculation of fluorescence forming pseudomonas and soil saprophytic fungi as Stachybotrys chatarum, Fusarium solani, and F. oxysporum. The results obtained were summarized as follows; 1. The concentration of siderophore in synthetic medium with inoculation of Pseudomonas putida pt-II was increased (with progress of incubation time). 2. The negative correlation was obtained with the increase of $Fe^{3+}$ ion concentration and siderophore in synthetic medium with inoculation of fluorescence forming pseudomonas and soil saprophytic fungi. 3. The fresh weight of fungal hyphae was decreased with the increase of siderophore in synthetic medium. 4. There was insignificant relationship between the concentration of $Mn^{2+}$ and the concentration of siderophore while the positive correlation was obtained with the increase of fresh weight of fungal hyphae.

• Journal of the Korean Society for Library and Information Science
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• v.42 no.3
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• pp.103-131
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• 2008

Today. the mental health has a great deal of impact on individuals and the society surrounding. Therefore. this research is to propose a way of bibliotherapical intercession by stages and patterns as to examine the recovery process of students with negative emotion by using the grounded theoretical method. This research collected materials through focus-interview, participant observation and book reports of 4 experiments involving female college students aged from 21 to 23, all having emotional and psychological difficulties. The recovery process of female students with negative emotion involved causal factors such as "recognition of hidden wound" "Sense of inferiority", and "difficulty in forming relationships", as well as contextual factors like "sympathetic attitude". which altogether brought about the core phenomenon. "pursuit for healthy ego". This core phenomenon induced to recovering the bright and positive attitude through using the strategies of 'self insight' and application of 'management plan', influence by such incoherent conditions as 'intimate surroundings' and $\setminus$ 'support system patterns'. And as time passed. the recovery process appeared tin four stages: 'issues recognition'. 'emotional responses', 'issue solution' and 'self application'.