• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.61-62
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• 2003

Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

• Korean Journal of Plant Resources
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• v.15 no.3
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• pp.237-242
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• 2002

Loaves, stems, cotyledons, and roots of Hovenia dulcis Thunb grown in test tube were cultured on media containing different concentrations of single or combined growth regulators. In MS media containing 2mg/ι BA, the shoot formation rate was 95.5% and it was the highest frequency of shoot formation. MS media showed most efficiency in the shoot formation at 0.01mg/ι TDZ for the callus formation, but the color of callus changed to brown at a higher concentration of TDZ. Callus formation was 89.% at 0.5mg/ 2.4-D, but IAA, IBA, and NAA were not effective on the formation of callus. Calli were formed only on wound area when IAA, IBA, and NAA were added into MS media. Combined growth regulators (BA + auxin) were more effective in roots and nodes than leaves and cotyledons on the formation of shoot. More than 97％ of shoot formation was obtained on MS media containing BA and auxin. For the production of multiple shoot, nodes of Hovenia dulcis were used and effect of growth regulators on the formation of multiple shoot was evaluated on MS media. Highest shoots (5.3) of Hovenia dulcis were induced on MS media supplied with 0.1mg/ι BA and 0.1mg/ι NAA, and an average of 6.4 shoots per explant were obtained in 1/2 MS media containing same concentration and growth regulators. An average of 7 shoots per explant after 4 weeks of culture from nodes of Hovenia dulcis was produced on a woody plant medium(WPM) containing 0.1mg/ι BA and 0.1mg/ι NAA. Shoot length was 6.0 cm in average.

• Journal of Gifted/Talented Education
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• v.16 no.1
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• pp.21-42
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• 2006

The object of this research is to analyze the contents and amount of articles on gifted education in major daily newspapers dated January 1990 to December 2003, and to review the trend of social perception of gifted education with the passage of time. Following are the research question : 1. How many articles belonging to the same category appeared in the newspapers within the period of time covered by the study? 2. What kinds of articles appeared in the newspapers within the period of time covered by the study? To arrive at the answers to the problems mentioned above, 714 articles on gifted education. The period from 1990 to 2003 were divided into time frames of 5 years to facilitate the analysis of social consciousness regarding gifted education before and after the enforcement of the Early School Entering Law in 1995 and the Law for Promotion of Gifted Education in 2000. The researcher defined Period I as the years from 1990 to 1994, Period II from 1995 to 1999, and Period III from 2000 to 2003. The articles were classified by content which were significance and trend of gilled education, current policies on gifted education, information on gifted education, and social environment of gifted education. The results of the analysis are as follows: (1) The articles from 1990 to 2003 totalled 714. 130 articles were found within Period I, 213 within Period II, and 371 within Period III. Since the year 2000, when the Law for Promotion of gifted education was enforced, the amount of articles considerably increased. The articles on the trend of gifted education numbered 42 within Period I, 49 within Period II, and 81 within Period III, showing a huge increase in the last period. The articles on current policies numbered 56 within Period I, 77 within Period II, and 143 within Period III, numbering the most in the last period. This means that, even before the Law for Promotion of gifted education was enforced, there has been much interest in and discussion of the appropriate educational system for gifted children in preparation for the legal and institutional foundation of such system. Since the enforcement of the law, many institutions were established and the problem became an important social issue. The articles that most frequently appeared were about current policies on and status of gifted education. This category showed the largest numbers through all the three periods and on all the subjects. This subject represented 43.1% of the articles on gifted children within Period I, 36.2% within Period II, and 38.6% within Period III. As to the significance and trend of gifted education, this subject showed a decrease from 32.3% within Period I, 23% within Period II, and 21.8% within Period III. However, the articles in the category of information on gifted education gradually increased from they represented 5.4% of the articles on brilliant children within Period I, 7.5% within Period II, and 8.4% within Period III. The social environment articles showed an increase from Period I to Period II-- from 19.2% to 33.3%, but it went down to 31.3% within Period III. (2) As to articles on the trend of gifted education, there were many such articles found, mainly on researches and trends in other countries. As greater importance is accorded to gifted children and as the recognition of the necessity of providing specific education for them grows, more related studies are conducted and people try to adopt new trends from other countries. For the articles on the current policies of gifted education, most of them were about institutions. This means that many educational institutions have been established since the Law for Promotion of Gifted Education was enforced. Informative articles on gilled education were mostly about distinctive features of gifted children and how to tell who the brilliant children are. This fact shows the importance of identifying gifted children in order to educate them systemically and effectively.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.636-641
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• 2005

Mulberry leaves, high in dietary fiber and some nutritional materials, are thought to have hypocholesterolemic effect. Therefore, effect of mulberry leaf powder on serum lipid profiles were studied using rats with diet-induced hypercholesterolemia. Male Sprague-Dawley rats were fed AIN-93 diet (control group), and diets containing high-cholesterol and 0% mulberry leaves powder, high-cholesterol and 5% mulberry leaves powder, and high-cholesterol and 10% mulberry leaves powder for 4 weeks. Hypercholesterolemia was induced by adding 1% cholesterol and 0.5% cholic acid to all diets except in control group. Although no differences were observed in food intake and initial body weight among groups, mulberry leaf treatment resulted in significant decreases in food efficiency ratio and body weight gain. Mulberry leaf treatment decreased serum lipid profiles, atherogenic index, cardiac risk factor, low density lipoprotein cholesterol ratio, serum aspartate transaminase, and liver lipid levels. High density lipoprotein cholesterol, total cholesterol, serum HDL-cholesterol, and fecal lipid levels increased, suggesting mulberry leaves could improve hyperlipidemia and liver action, thereby proventing cardiovascular disease.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1667-1678
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• 1999

Certain parts of 190 kinds of medicinal herbs and 171 kinds of original materials of food were extracted by methanol. The extracts were tested their microbial inhibition activities against several food spoilage microorganisms, Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli, Saccharomyces cerevisiae, Candida albicans, Penicillium citrinum, Aspergillus flavus and Aspergillus niger. The methanol extracts of Cornus officinalis, Evodia officinalis, Glycyrrhiza glabra, Salvia miltiorrhiza. Schizandrae fructus, Coptidis rhizoma, aroma hop and bitter hop were shown inhibitory effect on certain species of gram(+) bacteria. Aroma hop and bitter hop were shown inhibitory effect on certain species of gram(-) bacteria. The methanol extract of Salvia miltiorrhiza exhibited a strong antibacterial activities. It was purified by solvent fractionation, silicagel column chromatography, prep. TLC, prep. HPLC. The purified active substance was identified as cryptotanshinone by EIMS, $1^H-NMR,\;{13}^C-NMR$ and DEPT. Cryptotanshinone showed a strong antibacterial activity against gram positive bacteria $(MIC\;:\;3.91{\sim}62.50\;{\mu}g/mL)$. Especially, this compound was the most strong activity against Bacillus subtilis $(MIC\;:\;3.91\;{\mu}g/mL)$.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.1
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• pp.437-456
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• 2016

This study, based on the need for department of LIS education program that targets training of subject-special librarian, focuses on proving that such education can improve perception of subject-special librarian and strengthen career decision-making. This study is composed of two parts. First, this study investigates case studies about subject-special librarian cultivation. Second, this study includes a survey about subject-special librarian, improving understanding about subject-special librarian, and improving career decision-making which was carried out targeting students who take 'Medical Terms and MeSH', and 'Health & Medical Information Sources' courses. Results are as follows. First, most of the respondents felt the need for medical librarian and medical information services (88.7%), understood the role of medical librarian (92.5%), got to know more about the types and functions of medical information services (100%), and came to be more aware of the self-esteem a medical librarian feels as a professional. Second, relatively, the percentage of respondents who demonstrated the willingness to work at a medical library (45.3%) or work in the field of medical information services (26.4%) was noticeably low. Third, there were no statistical difference in whether the students took related courses or not, number of courses they took and difference in their school year, and in regard of the level of understanding of medical librarian and medical information services, those who took courses demonstrated higher understanding than did those who did not take those courses. Also, those who took the courses showed stronger willingness to work as a medical librarian. Fourthly, the curriculum carried out by the department of library and information service was effective in understanding medical librarian and medical information services, but makes students more cautious about deciding whether or not to start their career at a medical library. Lastly, it was recommended that there is a need to have the curriculum updated in order to help students overcome the difficulty and unfamiliarity they feel about medical subject.

• Journal of Life Science
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• v.16 no.4
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• pp.571-578
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• 2006

HtrA2/Omi, a mitochondrial trypsin-like serine protease, is pivotal in regulating apoptotic cell death. Several lines of recent evidence suggest that HtrA2 is associated with the pathogenesis of neurodegenerative disorders; however, the physiological function of HtrA2 still remains elusive. For studying physiological function of HtrA2 in depth, it is necessary to develop a suitable expression system in the model animal. We therefore utilized the zebrafish as a model animal to establish expression of human HtrA2 (hHtrA2) in vivo. For expression of mature HtrA2 as GFP fusion in zebrafish embryos, the HtrA2 (WT) or (S306A) cDNAs with the C-terminal GFP tag were inserted into the pCS2+ plasmid. Expression patterns of HtrA2 in HEK293 cells were first monitored by immunofluorescence staining and immunoblot assays, showing approximately 64 kDa of the HtrA2-GFP fusion proteins. Subsequently, the hHtrA2 plasmid DNA or in vitro transcribed mRNA was microinjected into zebrafish embryos. The expression patterns of HtrA2 in Zebrafish embryos were monitored by GFP fluorescence in 24 hours-post-fertilization (hpf). Although expression patterns of HtrA2-GFP in developing embryos were different between the injected DNA and mRNA, both nucleic acids revealed good expression levels to further study the physiological role of HtrA2 in vivo. This study provides a suitable condition for expressing hHtrA2 in the zebrafish embryos as well as a method for generating useful system to investigate physiological properties of the specific human genes.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1071-1079
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• 2006

The purpose of this study was to observe the effects of the feeding physiological activity substance in feral peach(Prunus Persica Batsch var. davidiana Max.) extract intake on the improvement of the lipid compositions, apolipoprotein and blood pressure level in spontaneously hypertensive rats(SHR, Wistar strain, male) fed the experimental diets for 33 days. Concentrations of total cholesterol, triglyceride(TG), LDL-cholesterol, free cholesterol and atherosclerotic index in serum were significantly lower in the feral peach extract intake groups[groups 5g% Ex.(basal diet+feral peach 5.0g% extract), 10g% Ex.(basal diet+feral peach 10.0g% extract)] than those in the group Control(basal diet+water). In the ratio of HDL-cholesterol concentration to total cholesterol and HDL-cholesterol concentration, feral peach 5.0g%, 10.0g% extract intake groups(group 5g% Ex. and 10g% Ex.) were higher percentage than in the group Control. However, concentrations of total cholesterol and TC in liver and brain were significantly lower in the groups 5g% Ex. and 10g% Ex. than those in the group Control. But the concentrations of apolipoprotein (Apo) A-I and Apo A-II in serum were significantly higher in the feral peach 5.0g% and 10.0g% extract intake groups(5g% Ex. and 10g% Ex.) than in the control group. However, concentrations of Apo C-II, Apo C-III, Apo E and ratio of Apo B to Apo A-I in serum were fairly reduced in the groups 5g% Ex. and 10g% Ex. than in the control group. The levels of systolic and diastolic blood pressure were significantly lower in feral peach 5g% Ex. and 10g% Ex. groups than control group. However, no significance was found in the effect of among the groups(groups 5g% Ex. and 10g% Ex.). From these results, physiological activity substance in feral peach(Prunus persica Batsch var. davidiana Max.) extracts were effective on the improvement of the lipid compositions and cardiovascular heart disease, hypertension in spontaneously hypertensive rats. And particularly, feral peach extracts were more effective as a therapeutic regimen for the control of blood pressure in hypertension.

• Journal of Life Science
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• v.17 no.10
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• pp.1447-1451
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• 2007

Through the screening of marine natural compounds that inhibit cancer cell proliferation, we previously reported that pectenotoxin-2 (PTX-2) isolated from marine sponges exhibits selective cytotoxicity against several cell lines in p53-deficient tumor cells compared to those with functional p53. However, the molecular mechanisms of its anti-proliferative action on malignant cell growth are not completely known. To further explore the mechanisms of its anti-cancer activity and to test whether the status of p53 in liver cancer cells correlates with their chemo-sensitivities to PTX-2, we used two well-known hepatocarcinoma cell lines, p53-deficient Hep3B and p53-wild type HepG2. We have demonstrated that PTX-2 markedly inhibits Hep3B cell growth and induces apoptosis whereas HepG2 cells are much more resistant to PTX-2 suggesting that PTX-2 seems to act by p53-independent cytotoxic mechanism. The apoptosis induced by PTX-2 in Hep3B cells was associated with the modulation of DNA fragmentation factor (DFF) family proteins, up-regulation of pro-apoptotic Bcl-2 family members such as Bax and Bcl-xS and activation of caspases (caspase-3, -8 and -9). Blockade of the caspase-3 activity by caspase-3 inhibitor, z-DEVD-fmk, prevented the PTX-2-induced growth inhibition in Hep3B cells. Moreover, treatment with PTX-2 also induced phosphorylation of AKT and extracellular-signal regulating kinase (ERK), but not c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MARK). Specific inhibitors of PI3K inhibitor (LY294002) and ERK1/2 inhibitor (PD98059) significantly blocks PTX-2-induced-anti-proliferative effects, whereas a JNK inhibitor (SP600125) and a p38 MAPK inhibitor (SB203580) have no significant effects demonstrating that the pro-apoptotic effect of PTX-2 mediated through activation of AKT and ERK signal pathway in Hep3B cells.

• Journal of Life Science
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• v.22 no.10
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• pp.1392-1398
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• 2012

This study investigated the effects of diet of different forages on growth performance and carcass characteristics of Hanwoo steers. Twenty-one Hanwoo steers were randomly allocated to three groups (fed hay, reed, and reed with rice straw) of seven steers each. Initial and final body weights of control, T1, and T2 groups were 125.5, 128.3, 128.3 kg and 697.4, 614.6, 706.7 kg, respectively. Average daily gain tended to increase in controls (0.70 kg/d) and the T2 group (0.71 kg/d) but not as much in the T1 group (0.60 kg/d); however, there was no significant difference. DMI was not significantly different among the treatment groups, but T1 was relatively lower than the other groups. For the yield traits, carcass weight was not significantly different between controls and the T2 group but was greater in the T2 group compared to the T1 group (p<0.05). Back fat thickness and rib eye area were higher in controls and T2 compared to T1; yield grade (A:B:C, %) was greater in T1 (43:57:0) compared to the other groups (control 0:71:29; T2 29:42:29). For the quality traits, fat color and texture were not significantly different among groups. However, meat color and maturity were significantly greater in T1 compared to T2 (p<0.05). Marbling score and appearance rate of over 1st meat quality grade were greater in the control and T2 groups compared to the T1 group. Based on the results, growth performance, feed utilization, and carcass traits appeared to improve when roughage containing rice straw plus reed was offered. Therefore, reed is worth considering as a roughage source for fattening Hanwoo steers.