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Typology of Korean Eco-sumers: Based on Clothing Disposal Behaviors (관우한국생태학적일개예설(关于韩国生态学的一个预设): 기우복장탑배적행위(基于服装搭配的行为))

  • Sung, Hee-Won;Kincade, Doris H.
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.1
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    • pp.59-69
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    • 2010
  • Green or an environmental consciousness has been a major issue for businesses and government offices, as well as consumers, worldwide. In response to this movement, the Korean government announced, in the early 2000s, the era of "Green Growth" as a way to encourage green-related business activities. The Korean fashion industry, in various levels of involvement, presents diverse eco-friendly products as a part of the green movement. These apparel products include organic products and recycled clothing. For these companies to be successful, they need information about who are the consumers who consider green issues (e.g., environmental sustainability) as part of their personal values when making a decision for product purchase, use, and disposal. These consumers can be considered as eco-sumers. Previous studies have examined consumers' purchase intention for or with eco-friendly products. In addition, studies have examined influential factors used to identify the eco-sumers or green consumers. However, limited attention was paid to eco-sumers' disposal or recycling behavior of clothes in comparison with their green product purchases. Clothing disposal behaviors are ways that consumer can get rid of unused clothing and in clue temporarily lending the item or permanently eliminating the item by "handing down" (e.g., giving it to a younger sibling), donating, exchanging, selling, or simply throwing it away. Accordingly, examining purchasing behaviors of eco-friendly fashion items in conjunction with clothing disposal behaviors should improve understanding of a consumer's clothing consumption behavior from the environmental perspective. The purpose of this exploratory study is to provide descriptive information about Korean eco-sumers who have ecologically-favorable lifestyles and behaviors when buying and disposing of clothes. The objectives of this study are to (a) categorize Koreans on the basis of clothing disposal behaviors; (b) investigate the differences in demographics, lifestyles, and clothing consumption values among segments; and (c) compare the purchase intention of eco-friendly fashion items and influential factors among segments. A self-administered questionnaire was developed based on previous studies. The questionnaire included 10 items of clothing disposal behavior, 22 items of LOHAS (Lifestyles of Health and Sustainability) characteristics, and 19 items of consumption values, measured by five-point Likert-type scales. In addition, the purchase intention of two eco-friendly fashion items and 11 attributes of each item were measured by seven-point Likert type scales. Two polyester fleece pullovers, made from fabric created from recycled bottles with the PET identification code, were selected from one Korean brand and one US imported brand among outdoor sportswear brands. A brief description of each product with a color picture was provided in the survey. Demographic variables (i.e., gender, age, marital status, education level, income, occupation) were also included. The data were collected through a professional web survey agency during May 2009. A total of 600 final usable questionnaires were analyzed. The age of respondents ranged from 20 to 49 years old with a mean age of 34 years. Fifty percent of the respondents were males and about 58% were married, and 62% reported having earned university degrees. Principal components factor analysis with varimax rotation was used to identify the underlying dimensions of the clothing disposal behavior scale, and three factors were generated (i.e., reselling behavior, donating behavior, non-recycling behavior). To categorize the respondents on the basis of clothing disposal behaviors, k-mean cluster analysis was used, and three segments were obtained. These consumer segments were labeled as 'Resale Group', 'Donation Group', and 'Non-Recycling Group.' The classification results indicated approximately 98 percent of the original cases were correctly classified. With respect to demographic characteristics among the three segments, significant differences were found in gender, marital status, occupation, and age. LOHAS characteristics were reduced into the following five factors: self-satisfaction, family orientation, health concern, environmental concern, and voluntary service. Significant differences were found in the LOHAS factors among the three clusters. Resale Group and Donation Group showed a similar predisposition to LOHAS issues while the Non-Recycling Group presented the lowest mean scores on the LOHAS factors compared to the other segments. The Resale and Donation Groups described themselves as enjoying or being satisfied with their lives and spending spare-time with family. In addition, these two groups cared about health and organic foods, and tried to conserve energy and resources. Principal components factor analysis generated clothing consumption values into the following three factors: personal values, social value, and practical value. The ANOVA test with the factors showed differences primarily between the Resale Group and the other two groups. The Resale Group was more concerned about personal value and social value than the other segments. In contrast, the Non-Recycling Group presented the higher level of social value than did Donation Group. In a comparison of the intention to purchase eco-friendly products, the Resale Group showed the highest mean score on intent to purchase Product A. On the other hand, the Donation Group presented the highest intention to purchase for Product B among segments. In addition, the mean scores indicated that the Korean product (Product B) was more preferable for purchase than the U.S. product (Product A). Stepwise regression analysis was used to identify the influence of product attributes on the purchase intention of eco product. With respect to Product A, design, price and contribution to environmental preservation were significant to predict purchase intention for the Resale Group, while price and compatibility with my image factors were significant for the Donation Group. For the Non-Recycling Group, design, price compatibility with the factors of my image, participation to eco campaign, and contribution to environmental preservation were significant. Price appropriateness was significant for each of the three clusters. With respect to Product B, design, price and compatibility with my image factors were important, but different attributes were associated significantly with purchase intention for each of the three groups. The influence of LOHAS characteristics and clothing consumption values on intention to purchase Products A and B were also examined. The LOHAS factor of health concern and the personal value factor were significant in the relationships with the purchase intention; however, the explanatory powers were low in the three segments. Findings showed that each group as classified by clothing disposal behaviors showed differences in the attributes of a product, personal values, and the LOHAS characteristics that influenced their purchase intention of eco-friendly products. Findings would enable organizations to understand eco-friendly behavior and to design appropriate strategic decisions to appeal eco-sumers.

Brief Introduction of Research Progresses in Control and Biocontrol of Clubroot Disease in China

  • He, Yueqiu;Wu, Yixin;He, Pengfei;Li, Xinyu
    • 한국균학회소식:학술대회논문집
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    • 2015.05a
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    • pp.45-46
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    • 2015
  • Clubroot disease of crucifers has occurred since 1957. It has spread to the whole China, especially in the southwest and nourtheast where it causes 30-80% loss in some fields. The disease has being expanded in the recent years as seeds are imported and the floating seedling system practices. For its effective control, the Ministry of Agriculture of China set up a program in 2010 and a research team led by Dr. Yueqiu HE, Yunnan Agricultural University. The team includes 20 main reseachers of 11 universities and 5 institutions. After 5 years, the team has made a lot of progresses in disease occurrence regulation, resources collection, resistance identification and breeding, biological agent exploration, formulation, chemicals evaluation, and control strategy. About 1200 collections of local and commercial crucifers were identified in the field and by artificiall inoculation in the laboratories, 10 resistant cultivars were breeded including 7 Chinese cabbages and 3 cabbages. More than 800 antagostic strains were isolated including bacteria, stretomyces and fungi. Around 100 chemicals were evaluated in the field and greenhouse based on its control effect, among them, 6 showed high control effect, especially fluazinam and cyazofamid could control about 80% the disease. However, fluzinam has negative effect on soil microbes. Clubroot disease could not be controlled by bioagents and chemicals once when the pathogen Plasmodiophora brassicae infected its hosts and set up the parasitic relationship. We found the earlier the pathogent infected its host, the severer the disease was. Therefore, early control was the most effective. For Chinese cabbage, all controlling measures should be taken in the early 30 days because the new infection could not cause severe symptom after 30 days of seeding. For example, a biocontrol agent, Bacillus subtilis Strain XF-1 could control the disease 70%-85% averagely when it mixed with seedling substrate and was drenching 3 times after transplanting, i.e. immediately, 7 days, 14 days. XF-1 has been deeply researched in control mechanisms, its genome, and development and application of biocontrol formulate. It could produce antagonistic protein, enzyme, antibiotics and IAA, which promoted rhizogenesis and growth. Its The genome was sequenced by Illumina/Solexa Genome Analyzer to assembled into 20 scaffolds then the gaps between scaffolds were filled by long fragment PCR amplification to obtain complet genmone with 4,061,186 bp in size. The whole genome was found to have 43.8% GC, 108 tandem repeats with an average of 2.65 copies and 84 transposons. The CDSs were predicted as 3,853 in which 112 CDSs were predicted to secondary metabolite biosynthesis, transport and catabolism. Among those, five NRPS/PKS giant gene clusters being responsible for the biosynthesis of polyketide (pksABCDEFHJLMNRS in size 72.9 kb), surfactin(srfABCD, 26.148 kb, bacilysin(bacABCDE 5.903 kb), bacillibactin(dhbABCEF, 11.774 kb) and fengycin(ppsABCDE, 37.799 kb) have high homolgous to fuction confirmed biosynthesis gene in other strain. Moreover, there are many of key regulatory genes for secondary metabolites from XF-1, such as comABPQKX Z, degQ, sfp, yczE, degU, ycxABCD and ywfG. were also predicted. Therefore, XF-1 has potential of biosynthesis for secondary metabolites surfactin, fengycin, bacillibactin, bacilysin and Bacillaene. Thirty two compounds were detected from cell extracts of XF-1 by MALDI-TOF-MS, including one Macrolactin (m/z 441.06), two fusaricidin (m/z 850.493 and 968.515), one circulocin (m/z 852.509), nine surfactin (m/z 1044.656~1102.652), five iturin (m/z 1096.631~1150.57) and forty fengycin (m/z 1449.79~1543.805). The top three compositions types (contening 56.67% of total extract) are surfactin, iturin and fengycin, in which the most abundant is the surfactin type composition 30.37% of total extract and in second place is the fengycin with 23.28% content with rich diversity of chemical structure, and the smallest one is the iturin with 3.02% content. Moreover, the same main compositions were detected in Bacillus sp.355 which is also a good effects biocontol bacterial for controlling the clubroot of crucifer. Wherefore those compounds surfactin, iturin and fengycin maybe the main active compositions of XF-1 against P. brassicae. Twenty one fengycin type compounds were evaluate by LC-ESI-MS/MS with antifungal activities, including fengycin A $C_{16{\sim}C19}$, fengycin B $C_{14{\sim}C17}$, fengycin C $C_{15{\sim}C18}$, fengycin D $C_{15{\sim}C18}$ and fengycin S $C_{15{\sim}C18}$. Furthermore, one novel compound was identified as Dehydroxyfengycin $C_{17}$ according its MS, 1D and 2D NMR spectral data, which molecular weight is 1488.8480 Da and formula $C_{75}H_{116}N_{12}O_{19}$. The fengycin type compounds (FTCPs $250{\mu}g/mL$) were used to treat the resting spores of P. brassicae ($10^7/mL$) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (A260) and at 280 nm (A280) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be lyzed by the FTCPs of XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol. In the five selected medium MOLP, PSA, LB, Landy and LD, the most suitable for growth of strain medium is MOLP, and the least for strains longevity is the Landy sucrose medium. However, the lipopeptide highest yield is in Landy sucrose medium. The lipopeptides in five medium were analyzed with HPLC, and the results showed that lipopeptides component were same, while their contents from B. subtilis XF-1 fermented in five medium were different. We found that it is the lipopeptides content but ingredients of XF-1 could be impacted by medium and lacking of nutrition seems promoting lipopeptides secretion from XF-1. The volatile components with inhibition fungal Cylindrocarpon spp. activity which were collect in sealed vesel were detected with metheds of HS-SPME-GC-MS in eight biocontrol Bacillus species and four positive mutant strains of XF-1 mutagenized with chemical mutagens, respectively. They have same main volatile components including pyrazine, aldehydes, oxazolidinone and sulfide which are composed of 91.62% in XF-1, in which, the most abundant is the pyrazine type composition with 47.03%, and in second place is the aldehydes with 23.84%, and the third place is oxazolidinone with 15.68%, and the smallest ones is the sulfide with 5.07%.

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Seedling Emergence of Dry -seeded Rice under Different Sowing Depths and Irrigation Regimes (건답직파에서 파종심도와 관개조건에 따른 벼 품종들의 출아특성)

  • 이변우;명을재
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.1
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    • pp.59-68
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    • 1995
  • Investigated were the relationships between plumule elongation characteristics and seedling emergence of 46 varieties including native, improved and red rice varieties of Korea, and varieties from U.S.A., Italy, India, Japan under 1, 3, and 5cm deep sowing with irrigated and non-irrigated condition. Experiments were carried out in paddy field of sandy loam. There was heavy shower of 19.2mm on the next day of seeding and thereafter, clear and dry weather continued during the experiment period. Soil temperature averaged over 30 days after seeding was $16.4^{\circ}C$ at 3cm depth. Soil hardness increased linearly up to 2.5kg /$cm^2$ on the 14th day after seeding, on which date irrigated plot was irrigated through furrow, and up to 4kg / $cm^2$ on the 28th day in non-irrigated plot. Soil hardness dropped near to 0kg /$cm^2$ after irrigation and developed up to 2.5kg /$cm^2$ again by 28 days after seeding. Seedling emergence was higher in irrigated plots than non-irrigated plots at all seeding depths. Korean improved varieties were substantially lower in seedling emergence under non-irrigated condition of 1 cm deep sowing than those under irrigated condition. This poor seedling emergence resulted mainly from delayed emergence by exposing them to greater soil strength. Percent seedling emergence under irrigated and non-irrigated condition showed signifi-cant correlations at 3 and 5 cm deep sowing. Korean improved varieties belonged to the group of poor seedling emergence, and I taliconaverneco, Chinsura Boro and Weld Pally to best group under both irrigation conditions at 3 and 5cm deep sowing. Seedling emergence showed highly signifi-cant positive correlation with the plumule length of mesocotyl + 1st internode + incomplete leaf and of mesocotyl+coleoptile. Among the characters constituting plumule length, incomplete leaf length showed greatest positive correlation followed by coleoptile and mesocotyl under irrigated condition at 3 and 5 cm deep sowing, and highest correlation with mesocotyllength followed by first internode and incomplete leaf under non-irrigated condition. Days to 50% seedling emergence at 1 cm deep sowing with irrigation showed great varietal variation of 10 to 30 days, and showed high significant negative correlations with percent seedling emergence under both irrigation conditions except for 1 cm deep sowing with irrigation, Days to seedling emergence revealed sig-nificant negative correlations with plumule characters except 2nd internode, showing highest cor-relation with incomplete leaf length.

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Analysis and Implication on the International Regulations related to Unmanned Aircraft -with emphasis on ICAO, U.S.A., Germany, Australia- (세계 무인항공기 운용 관련 규제 분석과 시사점 - ICAO, 미국, 독일, 호주를 중심으로 -)

  • Kim, Dong-Uk;Kim, Ji-Hoon;Kim, Sung-Mi;Kwon, Ky-Beom
    • The Korean Journal of Air & Space Law and Policy
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    • v.32 no.1
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    • pp.225-285
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    • 2017
  • In regard to the regulations related to the RPA(Remotely Piloted Aircraft), which is sometimes called in other countries as UA(Unmanned Aircraft), ICAO stipulates the regulations in the 'RPAS manual (2015)' in detail based on the 'Chicago Convention' in 1944, and enacts provisions for the Rules of UAS or RPAS. Other contries stipulates them such as the Federal Airline Rules (14 CFR), Public Law (112-95) in the United States, the Air Transport Act, Air Transport Order, Air Transport Authorization Order (through revision in "Regulations to operating Rules on unmanned aerial System") based on EASA Regulation (EC) No.216/2008 in the case of unmanned aircaft under 150kg in Germany, and Civil Aviation Act (CAA 1998), Civil Aviation Act 101 (CASR Part 101) in Australia. Commonly, these laws exclude the model aircraft for leisure purpose and require pilots on the ground, not onboard aricraft, capable of controlling RPA. The laws also require that all managements necessary to operate RPA and pilots safely and efficiently under the structure of the unmanned aircraft system within the scope of the regulations. Each country classifies the RPA as an aircraft less than 25kg. Australia and Germany further break down the RPA at a lower weight. ICAO stipulates all general aviation operations, including commercial operation, in accordance with Annex 6 of the Chicago Convention, and it also applies to RPAs operations. However, passenger transportation using RPAs is excluded. If the operational scope of the RPAs includes the airspace of another country, the special permission of the relevant country shall be required 7 days before the flight date with detail flight plan submitted. In accordance with Federal Aviation Regulation 107 in the United States, a small non-leisure RPA may be operated within line-of-sight of a responsible navigator or observer during the day in the speed range up to 161 km/hr (87 knots) and to the height up to 122 m (400 ft) from surface or water. RPA must yield flight path to other aircraft, and is prohibited to load dangerous materials or to operate more than two RPAs at the same time. In Germany, the regulations on UAS except for leisure and sports provide duty to avoidance of airborne collisions and other provisions related to ground safety and individual privacy. Although commercial UAS of 5 kg or less can be freely operated without approval by relaxing the existing regulatory requirements, all the UAS regardless of the weight must be operated below an altitude of 100 meters with continuous monitoring and pilot control. Australia was the first country to regulate unmanned aircraft in 2001, and its regulations have impacts on the unmanned aircraft laws of ICAO, FAA, and EASA. In order to improve the utiliity of unmanned aircraft which is considered to be low risk, the regulation conditions were relaxed through the revision in 2016 by adding the concept "Excluded RPA". In the case of excluded RPA, it can be operated without special permission even for commercial purpose. Furthermore, disscussions on a new standard manual is being conducted for further flexibility of the current regulations.

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Studies on the chemical composition of citrus fruits in Korea(II) -Changes of acid and sugar components with growth- (한국산(韓國産) 감귤류(柑橘類)의 화학성분(化學成分)에 관(關)한 연구(硏究) (II) -주요품종별(主要品種別) 당(糖) 및 산조성(酸組成)의 시기별(時期別) 변화(變化)에 관(關)하여-)

  • Park, H.;Kim, Y.S.;Kim, Z.U.
    • Applied Biological Chemistry
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    • v.9
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    • pp.41-57
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    • 1968
  • Changes of acids (total, titratable and combined form) and sugars (total, reducing and non-reducing) in the edible part and the rind of 17 varieties the in growing and ripening period were investigated. The results were summarized as follows. 1) The percentage of rind was notably decreased in growing period and slightly in the ripening period- It may suggest that the rates of translocation of metabolite from leaves to each part of fruit are different with growth phase. 2) The heavier the weight of fruit, the higher the percentage of rind was and the varieties having over 200 g per fruit showed the value over 30 in the rind percentage and over 15 in the number seeds per fruit. 3) Total acid contents in the rind were highest at the maximum grow th of fruit except in Citrus grandis having tie lowest value (below 20 me/100 g F.W). of total acid at maximum point in which total acid content is steadily increase. 4) Total acid and titratable acid in the edible part and total acid and combined acid in whole fruit life showed 0.933 and 0.970 of correlation coefficient significant at 1% level respectively, and most acid in the edible part was titratable acid(73%) whereas acid in the rind consists mostly of combined acid. 5) The content of combined acid in the ripening period increased in the edible part and decreased in the rind. It may be contributed to translocation of some cations from the rind to the edible part. 6) The grouping criteria on citrus fruit were applicable on melon, watermelon and tomatoes. 7) The contents of total sugar and non-reducing sugar in the edible part were continuously increased whereas the content of reducing sugar were decreased in certain varieties, notablly in citrus natsudaidai. The correlation coefficient between total sugar and reducing sugar in the edible part with ripening decreased as $0.849^{**},\;0.732^{**}.\;0.583^*$. ( $^{**}$: significant at 1% level and $^{*}:$: at 5%) 8) 61% of total sugar in the edible part was non-reducing sugar whereas 88% of total sugar in the rind was reducing form at the end of ripening and the correlation coefficient between total and non-reducing sugar in the edible part was 0.861 end total and reducing sugar in the rind was 0.972, both significant at 1% level. 9) Varieties having the percentage of the rind below 36 showed higher value than I in the ratio of total sugar in the edible part to one in the rind. It may suggest that there exists any intimate relation between relative sugar content and growth rate of fruit parts. 10) Citrus unshiu in Guje island showed lower values in the content of acid and sugar, and the rind percentage but higher sweetness index (the ratio of total sugar to titratable acid) comparing with the same variety in Jeiu.

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The Environmental and Ecological Meaning of Bibo Landscape in Otgol Village (옻골마을 비보경관의 환경생태적 의미)

  • Jang, Byoung-Kwan;Whang, Bo-Chul
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.2
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    • pp.32-41
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    • 2008
  • An empirical study and environmental and ecological analysis were conducted on Otgol Village(a village of the Gyeongju Choi's clan in Daegu) where an enclosed pond and groves are still observed. In particular, the enclosed pond and groves and village water system were investigated from an ecological perspective. The enclosed landscape is described based on feng shui principles and the environmental and ecological significance were examined. In general, the environmental and ecological significance is very broad; however, they were analyzed in terms of the quality of life as an empirical study as follows: First, water quality was measured to investigate the improvement of continuous water system functions. In other words, water quality was measured at East Valley(resting space), West Valley(living space), the enclosed pond where the two valleys merge, and the stream that flows out of the pond. Second, the climate functions of the enclosed groves that border the village were examined. In other words, temperature was measured in two places(200m distance from the center of the groves). Third, whether or not a sound ecosystem can be sustained was investigated. In other words, landscape ecological indicators were chosen and measured. The results are as follows: First, the enclosed pond played the role of purifying water quality. While the East Valley has been popular with men for its rock walls and torrents, the West Valley has been popular with women as a living space(ex: doing the laundry). Therefore, the difference of water quality can be explained. Second, since enclosed groves are in a small village forest, they are very weak in terms of being wind proof and temperature reduction effects. Instead, they play the role of the village boundary. Third, the groves are ecologically sound considering the landscape ecological indicators and are similar to ordinary traditional rural villages. In terms of the connection of the green zone, the village groves are well connected to the village boundary wood. If the village groves are restored, in particular, they would offer a decent habitat for grove creatures. According to this study, the traditional village space was formed upon the influence of Feng Shui theories that are based on environmental and ecological principles that focus on the harmony between humans and nature. From the environmental and ecological perspective, the enclosed pond and groves are important factors in building a sustainable village. The diverse water space would help to improve water quality and increase water volume by promoting the water circulation system. In addition, the village woods would surround the village and decrease the temperature and humidity difference between winter and summer. If the groves are small and badly damaged, however, they are meaningful only in dividing the region. The overall improvement of a forestation system and botanical composition may increase the biological diversity and promote the migration of species. Otgol Village has developed an enclosed landscape to improve the village environment. In other words, a sound and refreshing living environment can be developed when the natural ecological system is well understood and properly preserved. Additionally, this traditional village planning will be the environmental and ecological method. From the perspective of environmental ecology, therefore, a traditional village is recommended.

THE EFFECTS OF VARIOUS TETRACYCLINE HCL CONCENTRATION TREATED ROOW SURFACES ON PROLIFERATION AND SPREADING OF PERIODONTAL LIGAMENT CELLS (다양한 농도의 테트라사이클린로 처리된 치근면이 치주인대세포의 증식과 전개에 미치는 영향)

  • Jung, Oh-Chul;Sun, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.24 no.3
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    • pp.581-596
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    • 1994
  • This in vitro study was undertaken to obtain optimal tetracycline concentration that aids proliferation and spreading of human periodontal ligament cells, for clinical application in root surfaces of periodontally diseased teeth. Periodontal ligament cells used in this study were obtained from explants of periodontal ligament of 1st premolar teeth which were extracted for the purpose of orthodontic treatment. The cells were cultured in Dulbecco's Modified Eagle Medium(DMEM) supplemented with 100 U/ml penicillin, $100\;{\mu}g/ml$ streptomycin and 10% FBS at $37^{\circ}C$, 100% humidity, 5% $CO_2-95%$ air. Cells were used between the third to 4th passage. After root planing of periodontally extracted teeth, the root slabs were cut with carborundum disk. In the cell proliferation experiment, experimental groups were root planing only group, immersed groups in 25, 50, 75, 100, 150mg/ml aqueous solution of Tetracycline HCl followed by a vigorous rinse in PBS. Human PDL cells at concentration of $1{\times}10^5\;cells/ml$ were seeded in each culture well which contained root slabs and incubated for 6 hours. Then, all of the root slabs were moved into new 24 culture well and incubated 24, 48 and 72 hours. The cell counting was done by inverted phase contrast microscope after trypsinization. The following results were obtained. The cell number was increased in order root planing only group, 25, 150, 50, 75, 100mg/ml of Tetracycline HCl treated group in 24, 48 and 72 hours. The maximal cell number was obtained when the root slabs were immersed in solution with 100mg/ml of Tetracycline HCl. There were statistically significant between the root planing only group and 75, 100 mg/ml of Tetracycline HCl treated group in 24 hours, between the root planing only group and 100mg/ml of Tetracycline HCl treated group in 48 hours, between the root planing only group and 50, 75, 100mg/ml of Tetracycline HCl treated group, between 25 and 100mg/ml of Tetracycline HCl treated group in 72 hours(p<0.05). In the cell spreading experiment, after 30 minutes of incubated, in the root planing only group, the cells were generally round in shape. The cell surface was mostly covered with blebs. The cells started to attach to root surface by cytoplasmic extension in 50, 100mg/ml of Tetracycline HCl treated groups, more numerous cells attached to root surface than root planing only group. Many orifices of dentinal tubule were exposed, cells showed radially spreaded cytoplasm and unspreaded central region of the cell was covered with blebs. After 6 hours of incubation, in the root planing only group, cells showed radially spreaded cytoplasm and were attached flat appearance. In 50, 100mg/ml of Tetracycline HCl treated groups, cellular margin was concaved and cytoplasm showed elongated appearance with polarity. After 24 hours of incubation, in the root planing group, cells showed characteristic polarity. In 50, 100mg/ml of Tetracycline HCl treated groups, cells showed more elongated and spindle - like appearance.

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Effect of Exercise on Antioxidant Enzyme Activities of Skeletal Muscle and Liver in STZ-diabetic Rats (STZ-당뇨쥐에서 운동부하가 골격근 및 간의 항산화효소 활성도에 미치는 영향)

  • Seok, Kwang-Ho;Lee, Suck-Kang
    • Journal of Yeungnam Medical Science
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    • v.17 no.1
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    • pp.21-30
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    • 2000
  • Background: The purpose of the present study was to investigate the effect of exercise on the activities of antioxidant enzymes, super oxide dismutase(SOD), glutathione peroxidase(GPX) and catalase(CAT) of skeletal muscle(gastrocnemius) and liver in streptozotocin(STZ) induced diabetic rats. The malondialdehyde(MDA) concentration was also measured as an index of lipid poroxidation of tho tissues by exercise-induced oxidative stresses in diabetic rats. Material and Methods: Male Sprague-Dawley rats were randomly divided into control and STZ-induced diabetic rats. The STZ in citrate buffer solution was injected twice at S days intervals intraperitoneally(50, 70 mg/kg respectively). On the 28th day after the first STZ injection, the diabetic animals were randomly divided into pre- and post-exercise groups, The exercise was introduced to the rats of post-exercise group by treadmill running until exhaution with moderate intensity ($V_{O2max}$: 50-70%) of exercise. The duration of average running time was 2 hours and 19 minutes. Results: The blood glucose concentration was increased(p<0.001) and plasma insulin concentration was decreased(p<0.001) in the diabetic rats. The glycogen concentration in the muscle and liver was decreased by exhaustive exercise in the diabetic rats(p<0.001), In the skeletal muscle, the activities of GPX was increased(p<0.05) and the activities of SOD and CAT were not changed in the diabetic rats compare to those of the control rats. The activities of GPX was not changed by exercise but the activities of SOD(p<0.01) and CAT(p<0.01) were decreased by exercise in the diabetic rats, The concentration of MDA was not changed by exercise in diabetic rats, and the values of pre-exercise and post-exercise diabetic rats were not different from the value those of control rats, In the liver, the activities of SOD was decreased(p<0.01), and the activities of GPX and CAT were not changed in diabetic rats compared to the values of control rats, The activities of SOD, GPX and CAT were not changed by exercise in diabetic rats but the activity of SOD seemed to decrease slightly, The MDA concentration was increased in the diabetic rats compared to the values of control rats(p<0.001), but there was no change of MDA concentration by exercise in diabetic rats, Conclusions: In summary, exhaustive physical exercise did not seem to impose oxidative stress on the skeletal muscle because of due to oxygen free radicals, regardless of the decrease in SOD and CAT in the diabetic rats, In liver tissue, the tissue damage by oxidative stress was observed in diabetic rats but the additional tissue damage by exhaustive physical exercise was not observed.

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A study on The U.S.-Korean Trade Friction Prevention and Settlement in the Fields of Information and Telecommunication Industries (한미간(韓美間) 정보통신분야(情報通信分野) 통상마찰예방(通商摩擦豫防)과 해소방안(解消方案)에 관한 연구(硏究))

  • Jung, Jay-Young
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.13
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    • pp.869-895
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    • 2000
  • The US supports the Information and Communication (IC) industry as a strategic one to wield a complete power over the World Market. However, several other countries are also eager to have the support for the IC industry because the industry produces a high added value and has a significant effect on other industries. Korea is not an exception. Korea recently succeeded in the commercialization of CDMA for the first time in the world, after the successful development of TDX. Hence, it is highly likely to get tracked by the US. Although the IC industry is a specific sector of IT, there is a concern that there might be a trade friction between the US and Korea due to a possible competition. It will be very important to prepare a solution in advance so that Korea could prevent the friction and at the same time increase its share domestically and globally. It will be our important task to solve the problem with the minimum cost if the conflict arises unfortunately in the IT area. The parties that have a strong influence on the US trade policy are the think tank group and the IT-related interest group. Therefore, it would be important to have a close relationship with them. We found some implications by analyzing the case of Japan, which has experienced trade frictions with the US over the long period of time in the high tech industry. In order to get rid of those conflicts with the US, the Japanese did the following things : (1) The Japanese government developed supporting theories and also resorted to international support so that the world could support the Japanese theories. (2) Through continual dialogue with the US business people, the Japanese business people sought after solutions to share profits among the Japanese and the US both in the domestic and in the worldwide markets. They focused on lobbying activities to influence the US public opinion to support the Japanese. The specific implementation plan was first to open culture lobby toward opinion leaders who were leaders about the US opinion. The institution, Japan Society, were formed to deliver a high quality lobbying activities. The second plan is economic lobby. They have established Japanese Economic Institute at Washington. They provide information about Japan regularly or irregularly to the US government, research institution, universities, etc., that are interested in Japan. The main objective behind these activities though is to advertise the validity of Japanese policy. Japanese top executives, practical interest groups on international trade, are trying to justify their position by direct contact with the US policy makers. The third one is political lobby. Japan is very careful about this political lobby. It is doing its best not to give impression that Japan is trying to shape the US policy making. It is collecting a vast amount of information to make a correct judgment on situation. It is not tilted toward one political party or the other, and is rather developing a long-term network of people who understand and support the Japanese policy. The following implications were drawn from the experience of Japan. First, the Korean government should develop a long-term plan and execute it to improve the Korean image perceived by American people. Second, the Korean government should begin public relation activities toward the US elite group. It is inevitable to make an effort to advertise Korea to this elite group because this group leads public opinion in the USA. Third, the Korean government needs the development of a relevant policy to elevate the positive atmosphere for advertising toward the US. For example, we need information about to whom and how to about lobbying activities, personnel network who immediately respond to wrong articles about Korea in the US press, and lastly the most recent data bank of Korean support group inside the USA. Fourth, the Korean government should create an atmosphere to facilitate the advertising toward the US. Examples include provision of incentives in tax on the expenses for the advertising toward the US and provision of rewards to those who significantly contribute to the advertising activities. Fifth, the Korean government should perform the role of a bridge between Korean and the US business people. Sixth, the government should promptly analyze the policy of IT industry, a strategic area, and timely distribute information to industries in Korea. Since the Korean government is the only institution that has formal contact with the US government, it is highly likely to provide information of a high quality. The followings are some implications for business institutions. First, Korean business organization should carefully analyze and observe the business policy and managerial conditions of US companies. It is very important to do so because all the trade frictions arise at the business level. Second, it is also very important that the top management of Korean firms contact the opinion leaders of the US. Third, it is critically needed that Korean business people sent to the USA do their part for PR activities. Fourth, it is very important to advertise to American employees in Korean companies. If we cannot convince our American employees, it would be a lot harder to convince regular American. Therefore, it is very important to make the American employees the support group for Korean ways. Fifth, it should try to get much information as early as possible about the US firms policy in the IT area. It should give an enormous effort on early collection of information because by doing so it has more time to respond. Sixth, it should research on the PR cases of foreign enterprise or non-American companies inside the USA. The research needs to identify the success factors and the failure factors. Finally, the business firm will get more valuable information if it analyzes and responds to, according to each medium.

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Efficacy of Self-manipulation Technique in the Treatment of Patients with Anterior Disc Displacement without Reduction (비정복성 관절원판 전방변위 환자의 치료에 있어서 자가 수조작술의 효과에 대한 연구)

  • Kim, Ju-Sik;Lee, Chae-Hoon;Kim, Young-Ku
    • Journal of Oral Medicine and Pain
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    • v.32 no.4
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    • pp.441-447
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    • 2007
  • Internal derangement of the temporomandibular joint(TMJ) is defined as an abnormal relationship of the articular disc to the condyle. Mandibular manipulation is one of the conservative treatments to be considered first to manage the patients with anterior disc displacement without reduction. Mandibular manipulation is used to increase articular mobility and to restore the displaced disc into an anatomically normal position. While Farrar's technique has been popularly used, Minagi et al., Mongini and Suarez introduced the manipulation technique conducted by the patients themselves. But there is no study on the efficacy of self-manipulation technique, comparing with conventional one. The aim of this study was to investigate the efficacy of the conventional and self-manipulation technique, which was modified to complement the previously described technique by Minagi et al., in the treatment of patients with anterior disc displacement without reduction. TMD patients, who visited Department of Oral Medicine of Seoul National University Dental Hospital from December, 2002 to November, 2004 and were diagnosed as anterior disc displacement without reduction by TMJ magnetic resonance imaging (MRI) were enrolled. Conservative treatments including physical therapy, exercise, behavioral therapy, stabilization splint therapy, and manipulation therapy were done to every single patient until the symptomsimproved enough to discharge the patient. The charts were reviewed retrospectively according to the type of manipulation. In the results, patients whose maximum mouth opening was more than 40 mm was higher in the self-manipulation group(69.9%) than in the conventional manipulation group(42.9%). But difference between two groups was not significant. According to the fact that we decided to discharge the patients whentheir mouth opening increased to more than 40 mm and subjective symptoms such as pain and discomfort were improved as well, treatment period of discharged patients was significantly shorter in the self-manipulation group($29.2{\pm}12.3$ weeks) than in the conventional manipulation group ($61.0{\pm}38.0$ weeks) (p<0.01). In conclusion, in the treatment of TMD patients with anterior disc displacement without reduction, the self-manipulation technique which is performed by patients themselves is an effective treatment modality for increasing the range of mouth opening and shortening the total treatment period.