• 한국해양학회지
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• v.14 no.1
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• pp.15-25
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• 1979

A study on field bioassay test using four species of commercially important shellfish was carried out to assess the effect of pollutants and determine the extent of marine environmental pollution of the Masan Bay from 9 to 15 August 1978. Water quality analysis and planktological examination of sea water were made during the experiment and the examination gave the following results. The water temperature was so high at 31.7$^{\circ}C$ in maximum and rather subject to change on weather condition of the land than on the effect of the water mass from outer bay. The range of DO,COD and SS at the stations were 0.3-7.08cc/l, 0.07-3.31ppm and 5.5-117ppm, respectively with the high values of COD and SS at the stations 7 and 1. The concentrations of the dissolved inorganic nitrogen in sea water, NH$\sub$4/-N, NO$\sub$2/-N, NO$\sub$3/-N, and PO$\sub$4/-P were 18.90-99.80, 2.48- 19.60, 13.00-39.00 and 1.04-14.0$\mu\textrm{g}$ at/l, respectively with decrease of their values in the outer part of the Bay. The high values mentioned above were caused by the sewage and industrial activities. The effects of organic waste are increased oxygen demand, nutrient concentration, turbidity and a higher input of pathogens, leading to structural changes in the marine ecosystems and to a considerable hazard to public health. The percentage composition of phytoplankton standing crop between diatom and dinoflagellate was characterized by making a difference between the two groups in respect of location: a decrease of diatom and a increase of dinoflagellate in numerical abundance toward inner part from outer part of the bay. Namely phytoplankton organisms were composed of 80% of diatom and 20% of dinoflagellate in outer bay, on the contrary, only 4% of diatom and 96% of dinoflagellate occupied by 94% of prorocentrum micans known as tolerant species to polluted reaas in the inner bay. On the occurrence and composition of zooplankton, there are two significant communities in the bay:one is characterized by the predominance of Oithona nana and the other by Favella sp They were composed of a range from 84% to 90% of the total organisms and monotonously constituted of themselves only at most inner station 3 even small numbers. From the results mentioned above, Oithona nana, Favella and prorocentrum micans recommed themselves as valuable indicators for judging the extent of the marine pollution.During the period of the biossays Mytilus edulis showed the highest mortality and Tapes japonica the lowest one between the four test species. The highest death rate by stations was found at most inner stations 3'and 4near Masan Free Export Zone with the most sensitive response and the lowest one occured at outer station 13 where no death specimen of oyster and arkshell was found during the whole test period.As for mussel,85 percent death rate appeared after 72 hours and 100percent rate after 120hours at station 4. It was found that the significant high mortality of the test shellfish mentioned above was caused by severe pollution with mainly organic pollutants from domestic sewage and industrial wastes from the results of too much higher concentrations of dissolved inorganic nitrogen especially ammonia-N,COD,SS and lack of dissolved oxygen,and furthermore occurrence and abundance composition of Prorcentrum,Favella and Oithona nana by stations, valuable indicator species of coastal pollution by orgnic and boilogical pollutants.

• The Korean Journal of Mycology
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• v.20 no.4
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• pp.337-346
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• 1992

Trichoderma spp. are an effective control agent for damping-off or other plant diseases. The interaction between. T. hamatum and Rhizoctonia solani on the rhizosphere or surface soil were examined to assess the possible roles of antibiosis or competition in the mechanisms of biological control agents as a basic research. In a proportional comparison, total bacteria, fungi, actinomycetes and Trichoderma spp were 65%, 8.8%, 25.9% and 0.28% respectively in their distribution in the soil. Among Trichoderma spp isolated, the 5 species of Trichoderma spp were indentified as T. koninggii, T. pseudokoninggii, T. aureoviridi, T. hamatum and T. viride respectively. In a mycoparasitic test, one isolate of T. hamatum strain Tr-5 showed an enzymatic ability to break fungal hyphae into piecies and infected on the R. solani hyphae showing a parasitism. Spore germination of the all isolates of Trichoderma spp showed a 1.7-7.3% of germination in natural soil conditions, but the percentage was high in sterile soil indicating all the natural soil were fungistatic on conidia of Trichoderma spp. In rhizosphere competent assay in pea plant, the antagonistic T. hamatum, T. viride, T. koninggii, T. pseudokoninggii showed a colonizing upper soil depth in rhizosphere around 1-3 cm in root zone, but the colonizing ability was much reduced along the deeper the soil depth. Propagule density was decreased in deeper the soil layer. Disease development rate treated alone with plant pathogens, Fusarium solani, Rhizoctonia solani, Cylindrocarpon destructans increased, but disease incidence rate reduced in treatment with combinations with antagonistic T. hamatum strain Tr-5.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.3
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• pp.303-310
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• 2007

Sweetpotato shoot tops (leaves, tips and petioles) are known to be very useful parts as vegetables because of their high nutritive values and great biomass yield. In this study, the phenolic compound contents, antibacterial activity, mutagenic activity, and antimutagenic activity were investigated in sweetpotato tips that were 10-15cm of shoot top including stems, petioles and tender leaves after sprout of storage roots. The study was done by extracting sweetpotato tips with 80% ethanol and the ethanol fraction was re-extracted with hexane, chloroform, ethyl acetate, butanol and water. In ethyl acetate and butanol fractions, total phenolic compounds contained 95. 6mg/g extract and 69.3 mg/g extract, respectively, The antibacterial activity was measured using the paper disk method with concentrations of 1, 2, 5 and 10 mg/disk of butanol and ethyl acetate fractions against L. monocytogenes and S. Typhimurium strains. Higher doses of solvent extracts showed the higher antibacterial activities. In addition, 5, 10 and 20 mg/mL of the extracts were tested to determine the antibacterial activity in liquid culture. The sweetpotato leaf extract by ethyl acetate showed 1 log reduction compared to control after 24 hrs on Listeria monocytogenes, but 20 mg/ml of butanol extract completely inhibited the growth of the pathogen after 12 hrs. The extracts from ethyl acetate or butanol on Salmonella Typhimurium did less than 1 log reduction during cultivation compared to control. The numbers of S. Typhimirium TA98 and TA100 revertant colonies were 29-33 and 159-188 CFU/plate, respectively, indicating that solvent extracts were no mutagenic activity. The antimutagenic test was performed by adding direct mutagen 2-NF and MMS, and butanol and ethyl acetate showed antimutagenic effect. Thus, this study showed that sweetpotato tips had high phenolic contents and both antimicrobiol and antimutagenic properties. Sweetpotato tips would be good nutritive source because of their high nutrient content without any toxicity in consuming.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.1
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• pp.40-46
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• 2020

In this study, we examined the quality of fish cakes prepared using the flour obtained from the following different rice varieties: Baekogchal, Dodamssal, Hangaru, Jeogjinju 2, Josaengheugchal, Saeminyeon, Saeilmi, and Shingil. The moisture content of the fish paste containing rice flour ranged from 67.40% to 69.90%, and was highest in the paste prepared using Baekogchal flour. The lipid and protein contents of the paste ranged from 0.05% to 0.43% and 11.36% to 11.69%, respectively, whereas the carbohydrate content was between 10.36% and 12.32%, and was highest in the paste prepared using Jeogjinju 2 flour. Fish cakes prepared using the flour from Baekogchal, Jeogjinju 2, and Josaengheugchal rice were found to have the hardest consistency. Sensory evaluations indicated that fish cakes prepared using Shingil flour had the best texture. Furthermore, the total polyphenol content was significantly higher in the fish cakes prepared using Josaengheugchal flour (165.12 mg GAE/100 g), whereas the DPPH and ABTS radical scavenging activities were significantly higher in the fish cakes prepared using Josaengheugchal flour (39.37 and 175.37 mg TE/100 g, respectively). In conclusion, we confirmed that the quality of fish cakes is affected by the characteristics of the flours obtained from different rice varieties. Among the varieties assessed, the quality of Shingil and Josaengheugchal varieties was suitable for preparing rice-containing fish cakes.

• Journal of Science Education
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• v.34 no.1
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• pp.58-71
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• 2010

The purpose of this study is to categorize preconceived notions by elementary science gifted students about the reason why only one side of the moon is visible and develop an instructional module to correct these notions scientifically. The effectiveness of these modules will then be tested. The participants of this study were 15 (5th and 6th grade students) from Gwangju Metropolitan City and Chonnam Province who passed a gifted student assessment test developed by J university. The student's notions about the reason only one side of the moon is visible were assessed through questionnaires, interviews, and reenactments. Instructional modules to minimize these notions were developed and then improved upon by class reenactments. And then these modules were used to teach a real class with cameras recording the students. Protocols were analyzed using this footage, and emphasis was placed on how the developed class module changed student's misconceptions. The instructional module developed in this study was: student conception assessment writing materials exploration activity stage 1 (moon's orbit) exploration activity stage 2 (moon's rotation) - exploration activity stage 3 (moon's orbit and rotation) - exploration activity stage 4 (verbalizing the moon's orbit and rotation) - exploration activity stage 5 (thinking about moon movement considering earth's rotation - exploration activity stage 6 (relating the earth and moon's movement) and verifying student conception change. An important conclusion of this study was that all 15 students had misconceptions that could be divided into categories A, B, and C. Category A could be separated with more specifics into A-1 and A-2, and C into C-1 and C-2. After the instructional module was utilized, the student categories show positive change in the following stages: Category A at exploration activity stage 1 and 2, Category B at exploration activity stage 3, Category C-1 at exploration activity stage 4 and 5, and Category C-2 at exploration activity stage 6. Category C-1 students immediately changed to Category C-2 after going through a few stages, and their misconceptions were finally corrected after going through exploration activity stage 6. The misconceptions of students in all categories were corrected scientifically after completing stage 6 education. This study proposes that a combined education of reenactments, exploration materials development, and exploration activities by stages will effectively correct misconceptions about the Earth and moon's movement.

• Journal of the Korean Society for Library and Information Science
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• v.12
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• pp.269-327
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• 1985

This study was undertaken to meet more fully the demands for improved training of library personnel, occasioned by the rapidly changing roles and functions of libraries as they try to adapt to the vast social, economic and technological changes currently in progress in the Korean society. The specific purpose of this research is to develop a standard curriculum at the batchelor's level that will properly equip the professional personnel in Korean libraries for the changes confronting them. This study started with the premise that to establish a sound base for curriculum development, it was necessary first to determine what concepts, knowledge, and techniques are required for professional library personnel to perform it at an optimal level of efficiency. Explicitly, it was felt that for the development of useful curricula and courses at the batchelor's level, a prime source of knowledge should be functional behaviours that are necessary in the job situation. To determine specifically what these terminal performance behaviours should be so that learning experience provided could be rooted in reality, the decision was reached to use a systems approach to curriculum development, which is an attempt to break the mold of traditional concepts and to approach interaction from an open, innovative, and product-oriented perspective. This study was designed to: (1) identify what knowledge and techniques are required for professional library personnel to perform the job activities in which they are actually engaged, (2) to evaluate the educational needs of the knowledge and techniques that the professional librarian respondents indicate, and (3) to categorise the knowledge and techniques into teaching subjects to present the teaching subjects by their educational importance. The main data-gathering instrument for the study, a questionnaire containing 254 items, was sent to a randomly selected sample of library school graduates working in libraries and related institutions in Korea. Eighty-three librarians completed and returned the questionnaire. After analysing the returned questionnaire, the following conclusions have been reached: (A) To develop a rational curriculum rooted in the real situation of the Korean libraries, compulsory subjects should be properly chosen from those which were ranked highest in importance by the respondents. Characters and educational policies of, and other teaching subjects offered by, the individual educational institution to which a given library school belongs should also be taken into account in determining compulsory subjects. (B) It is traditionally assumed that education in librarianship should be more concerned with theoretical foundations on which any solution can be developed than with professional needs with particulars and techniques as they are used in existing library environments. However, the respondents gave the former a surprisingly lower rating. The traditional assumption must be reviewed. (C) It is universally accepted in developing library school curricula that compulsory subjects are concerned with the area of knowledge students generally need to learn and optional subjects are concerned with the area to be needed to only those who need it. Now that there is no such clear demarcation line provided in librarianship, it may be a realistic approach to designate subjects in the area rated high by the respondents as compulsory and to designate those in the area rated low as optional. (D) Optional subjects that were ranked considerably higher in importance by the respondents should be given more credits than others, and those ranked lower might be given less credits or offered infrequently or combined. (E) A standard list of compulsory and optional subjects with weekly teaching hours for a Korean library school is presented in the fourth chapter of this report.

• Journal of Life Science
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• v.26 no.1
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• pp.34-41
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• 2016

Black chokeberries (scientific name Aronia melanocarpa) have been reported to have major effects due to anti-oxidant, anti-inflammatory, and anti-cancer capabilities. In this study, we investigated the anti- wrinkle effects of A. melanocarpa, including collagenase inhibition effects and their molecular biological mechanisms, such as oxidative stress-induced matrix metalloproteinase (MMP), mitogen-activated protein (MAP) kinase, and activator protein (AP)-1 expression and/or phosphorylation. In collagenase inhibition activity, the ethyl acetate fraction of black chokeberry (AE) was 77.2% at a concentration of 500 μg/ml, which was a significant result compared to that of Epigallocatechin gallate (positive control, 83.9% in 500 μg/ml). In the reactive oxygen species (ROS) assay, the AE produced 78% of ROS in 10 μg/ml and 70% of ROS in 75 μg/ml, which was a much lower percentage than the ROS production of H₂O₂-induced CCRF S-180II cells. In the MTT assay, cell viability was increased dose-dependently with AE in H₂O₂-induced cells. In protein expression by western blot assay, the AE suppressed the expression and phosphorylation of MMPs (MMP-1, -3, -9), MAPK (ERK, JNK, and p38), and AP-1 (c-Fos and c-Jun), and expressed the pro-collagen type I in H₂O₂-induced cells. These results suggest that black chokeberries have anti-wrinkle and collagen-production effects, and they may be used in applications for material development in the functional food and cosmetic industries.

• Journal of Life Science
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• v.27 no.2
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• pp.187-193
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• 2017

As a part of ongoing research to elucidate and characterize antiinflammatory nutraceuticals, the crude extracts from Atriplex gmelinii C. A. Mey. and their solvent-partitioned fractions were tested for their antiinflammatory potential in lipopolysaccharide (LPS)-stimulated RAW 264.7 mouse macrophages. The crude extracts of A. gmelinii C. A. Mey. were fractioned according to polarity with n-hexane, 85% aqueous methanol (85% aq. MeOH), n-butanol, and $H_2O$. Their antiinflammatory activities were investigated in LPS-induced inflammation in mouse macrophages by measuring nitric oxide (NO) generation and mRNA expression of inflammation mediators, namely, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-$1{\beta}$ ($IL-1{\beta}$), and IL-6. As a result, we confirmed that the crude extracts of A. gmelinii C. A. Mey. inhibited LPS-stimulated NO production and mRNA expression of iNOS and COX-2 as important inflammatory factors. The inhibition of NO production through the downregulation of important inflammatory factors such as iNOS, COX-2, $IL-1{\beta}$, and IL-6 was found by treatment with all solvent-partitioned fractions. Among all tested fractions, 85% aq. MeOH showed the strongest antiinflammatory response. Based on the current results, A. gmelinii C. A. Mey. was suggested to possess natural antiinflammatory components, indicating that it could be used as a valuable source of antiinflammatory substances.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.2
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• pp.119-135
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• 2014

This study is aimed at understanding the factors behind deciding to accept a social network service (SNS) from the viewpoint of tourists who are users of tourism SNS. The study also seeks to clarify the effects these deduced factors have on the intention of users to continuously use SNS. To this end, individual properties (such as self-efficacy, socio-cultural effects, social presence and people's innovativeness), systematic properties (like system quality and information quality)and usefulness/availability were used as factors with regard to the decision to accept tourism SNS based on previous studies and efforts were made to structurally clarify the effects of such previous factors on people's intention to continuously use SNS through perceived value and satisfaction. SNS had significant effects on satisfaction and, furthermore, significantly affected tourists' intention to continuously use it. Based on such study results, factors behind deciding to accept SNS from the viewpoint of tourists affected customers' perceived value and satisfaction and ultimately affected their intention to continuously use SNS. To achieve the purpose of the study, a survey was conducted on about 250 Busan residents who had used SNS in relation to tourist activities, such as exhibitions, conventions, accommodation, trips, aviation service and transportation. According to an empirical study, factors behind deciding to accept tourism SNS, including individual properties, systematic properties and usefulness/availability had statistically significant effects on perceived value. The usefulness/availability factor had the largest influence, in particular, followed by the systematic factor and individual factor. The value perceived in the process of using tourism SNS had significant effects on satisfaction and, furthermore, significantly affected tourists' intention to continuously use it. Based on such study results, factors behind deciding to accept SNS from the viewpoint of tourists affected customers' perceived value and satisfaction and ultimately affected their intention to continuously use SNS.

• Korean Journal of Health Education and Promotion
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• v.1 no.1
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• pp.83-97
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• 1983

The present study is to provide information for the improvement of school health services through research on the current condition of its organization and practice in universities, colleges and junior colleges. The scope of this study is consisted of four components including health organizations/units, school health services, environmental sanitation and health education for the 30 universities, the 20 colleges and the 32 junior colleges in Korea. The major findings are summarized as follows: (1) Among the sampled schools, around 73% of them have the health service organization/unit. When we break down health service organization/unit into the types by the level of school, around 73% of the universities have formal organization called "health center" and 20.0% of them have an informal organization called "health room". For the colleges level, 30.0% of them have the "health center" and 40.0% of them have the "health room". The figure of junior colleges is a quite different from universities and colleges, 56.3% of junior colleges have the "health room" only but the other have no service organization at all. (2) It was found that only 22.0% of 82 schools have the health committee for the school health services. It might be necessary to have a kind of expert committee to establish an annual health service program, budget and health policy in the school. (3) Approximately 29% of those schools having formal health organizations/units appointed directors as a medical persons. 13.4% of the sampled schools are appointed doctors (including the dentists) at health service organization/unit, 9.8% are appointed pharmacist and 65.9% are appointed nurses. Therefore, the data imply that the school health services are depending mainly on nurses. (4) The major activities of school health services are covering primary medical care (84.1%), health counseling (72.0%), physical examination (68.3%), vaccination (58.5%), tuberculosis control (54.9%), parasite control (29.3%) and dental health case(9.8%). Also 69.5% of the schools have the program on the environmental sanitation and the health education program. (5) In regard to health budget taking account of 34 schools, approximately 92% of them have less than 5,000 won per students and only 8.8% of them have more 10,000 won per students. At the average health budget per students is 4089.8 won in universities, 1617.1 won in colleges and 475.0 won in junior colleges. (6) The students enjoy the benifit of medical insurance at 11.0% of 82 schools surveyed. They are all universities. (7) The study found that 56 universities, colleges and junior colleges provide the annual physical examination. Only 21.4% of them have provided it for all students and school employees. (8) 64.3% of the 56 schools surveyed keep a record of the regular physical examinations. Records must be utilized as the basic data for the evaluation of the student's health condition and so the individual student is encouraged to take care of his own health. (9) At the 59 schools which practice health counseling, the main concerns of the counsellees are venereal disease, tuberculosis and psychoneurosis. This shows the need to practice health education in the area of preventive medicine. (10) 69.5% of the 82 universities, colleges and junior colleges surveyed are concerned with supervision of the environmental sanitation in their school, but non-professionals are in charge at 70.1% of them. This indicates negligence in environmental sanitation. (11) 53.7% of the 82 schools responded that they have no special instructive measure for the students' health and 54.9% are found to be negative in the use of a health education method. This reveals a problem. They are not positive to the recognition of their function as the initiative organization for the students' health. (12) The supplementary education for the faculty of the school health services is executed only at 8.5% of all the schools surveyed.