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Ameliorating effect of the ethyl acetate fraction of Pteridium aquilinum on glucose-induced neuronal apoptosis (포도당으로 유도된 신경세포 손상에 대한 고사리 아세트산에틸 분획물의 개선 효과)

  • Park, Seon Kyeong;Guo, Tian Jiao;Kim, Jong Min;Kang, Jin Yong;Park, Sang Hyun;Kang, Jeong Eun;Kwon, Bong Seok;Lee, Chang Jun;Lee, Uk;Heo, Ho Jin
    • Korean Journal of Food Science and Technology
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    • v.49 no.4
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    • pp.430-437
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    • 2017
  • The protective effect of Pteridium aquilinum on high glucose-induced cytotoxicity was examined in vitro to investigate the relationship between diabetic condition and neuronal dysfunction. The ethyl acetate fraction of P. aquilinum (EFPA), with total phenolic content of 265.08 mg gallic acid equivalent/g, showed higher 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)/2,2-diphenyl-1-picrylhydrazyl radical scavenging activities and lipid peroxidation inhibitory effect than any other fraction. In addition, EFPA showed a significant reduction in the inhibitory effect on ${\alpha}$-glucosidase activity ($IC_{50}$ value=$205.26{\mu}g/mL$) compared to the acarbose positive control. The anti-oxidative effect in PC12 cells, protective effects on high glucose-induced oxidative stress in neuronal cells, and neurotoxicity were measured using 2',7'-dichlorofluorescin diacetate, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide, and lactate dehydrogenase assays, respectively. EFPA showed conspicuous inhibitory effect on cellular reactive oxygen species production and neuronal cell apoptosis. Finally, kaempferol-3-glucoside was identified as the main phenolic compound of EFPA using high performance liquid chromatography.

Workplace Friendship and Organizational Effectiveness of Dental Hygienists (치과의료기관 근무자들의 프렌드십과 조직효과성 관계 연구)

  • Yoo, Youngsuk;Seo, Youngjoon;Kim, Sungho
    • Journal of dental hygiene science
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    • v.12 no.6
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    • pp.644-651
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    • 2012
  • This study purports to measure the level of work friendship in dental clinic and examines the friendship's effect on the organizational effectiveness. Data were collected from workers who worked in dental clinic located in Seoul and Gyeonggi areas by self-administered questionnaires from early in October till lately in September, 2009 through direct interview and e-mail. Among 250 questionnaires, 240 responses were returned, and 17 copies with an inaccurate answer were excluded. Finally 223 responses were analyzed through SPSS program. The study revealed that the work friendship in dental clinic has enormous influence on job satisfaction, occupational commitment, intent to leave, stress etc. The results imply that the managers of the dental clinics need to create an organizational climate which emphasizes on a good relationship among members and have them take part in various committees or informal activities.

Effects of acid-treatment conditions on the surface properties of the RBM treated titanium implants (산-처리 조건이 RBM처리한 티타늄 임플란트의 표면 특성에 주는 영향)

  • Lee, Han-Ah;Seok, Soohwang;Lee, Sang-Hyeok;Lim, Bum-Soon
    • Korean Journal of Dental Materials
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    • v.45 no.4
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    • pp.257-274
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    • 2018
  • The purpose of this study was to evaluate the effect of acid-treatment conditions on the surface properties of the RBM (Resorbable Blast Media) treated titanium. Disk typed cp-titanium specimens were prepared and RBM treatments was performed with calcium phosphate ceramic powder. Acid solution was mixed using HCl, $H_2SO_4$ and deionized water with 4 different volume fraction. The RBM treated titanium was acid treated with different acid solutions at 3 different temperatures and for 3 different periods. After acid-treatments, samples were cleaned with 1 % Solujet solution for 30 min and deionized water for 30 min using ultrasonic cleanser, then dried in the electrical oven ($37^{\circ}C$). Weight of samples before and after acid-treatment were measured using electric balance. Surface roughness was estimated using a confocal laser scanning microscopy, crystal phase in the surface of sample was analyzed using X-ray diffractometer. Surface morphology and components were evaluated using Scanning Electron Microscope (SEM) with Energy Dispersive X-ray spectroscopy (EDX) and X-ray Photoemission Spectroscopy (XPS). Values of the weight changes and surface roughness were statistically analyzed using Tukey-multiple comparison test (p=0.05). Weight change after acid treatments were significantly increased with increasing the concentration of $H_2SO_4$ and temperature of acid-solution. Acid-treatment conditions (concentration of $H_2SO_4$, temperature and time) did not produce consistent effects on the surface roughness, it showed the scattered results. From XRD analysis, formation of titanium hydrides in the titanium surface were observed in all specimens treated with acid-solutions. From XPS analysis, thin titanium oxide layer in the acid-treated specimens could be evaluated. Acid solution with $90^{\circ}C$ showed the strong effect on the titanium surface, it should be treated with caution to avoid the over-etching process.

A Study on the Environmental Characteristics of Water Quality and Sediments in Suncheon Bay (순천만 수저질 환경특성에 관한 연구)

  • Park, Sangsook;Heo, Sung-sil;Choi, Jeong-min;Woo, Sung-won
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.10a
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    • pp.9-10
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    • 2019
  • 순천만은 순천시의 남쪽에 위치하여 여수반도와 고흥반도의 사이에 있는 만 지형 형태로 만 전체를 순천만이라고도 하나, 보통 고흥군반도와 여수반도 사이의 만을 여자만이라 하고 만내부에 위치한 여자도라는 섬의 위쪽으로 순천시의 해안하구에 형성된 지역을 순천만이라 일컫는다. 순천만은 순천시에서 유입되는 동천과 이사천 및 해룡천의 하류에 형성되어 있어서 육지부에서 유입되는 퇴적물과 유기물로 인하여 갯벌과 갈대등이 잘 형성된 습지로서 2003년 12월 31일 해양수산부 갯벌 습지보존지역으로 지정되어 관리되고 있으며, 2004년에는 동북아 두루미 보호 국제네트워크에 가입하였고, 2006년 1월 국내 연안습지로는 최초로 람사르협약에 "Suncheon Bay"로 등록되었으며, 2016년 6월에는 람사르습지로 지정된 국내외적으로 중요한 습지이다. 순천만습지에 형성되어 있는 갯벌($28.0km^2$)은 세계 5대 연안습지 중 하나로서, 넓은 사니질 갯벌과 갈대군락이 잘 발달되어 있는 생태계의 보고(寶庫)이자 소중한 생태자원으로서, 순천시에서는 순천만을 자연생태공원으로 지정하여 보호 관리하고 있으며, 각종 자연학습자료들과 영상물들을 갖춘 생태전시관과 갈대숲 탐방로, 용산전망대, 야생화 정원, 담수습지, 갈대정자, 갯벌관찰대 등 사계절 생태체험을 위한 각종 시설들을 잘 갖춰놓고 많은 관광객의 이용할 수 있도록 하고 있다. 갯벌은 바닷가의 넓은 벌판이란 뜻으로서 삼면이 바다인 우리나라는 갯벌의 전체 면적이 약 $2,500km^2$에 달하는데 여기에는 많은 종류의 다양한 생물들이 살아가고 있으며 어민들의 생계에 지대한 영향을 주고있다. 이러한 갯벌은 퇴적된 입자의 구성에 따라 펄갯벌, 모래갯벌, 혼합갯벌 등으로 구별되는데 이에 따라 갯벌 생태계를 구성하고 있는 생물들의 종류도 바뀌게 된다. 순천만갯벌과 여기에 조성되어 있는 습지환경에 따라 확인되고 있는 수산자원으로는 새꼬막, 꼬막, 눈알고둥, 갯고둥, 비툴이고둥, 돌조개, 접시조개, 새알조개, 가무락조개, 바지락, 우럭, 가재붙이, 방게, 칠게, 농게 등의 저서 생물들과 짱뚱어, 문절망둑 등의 어류가 있으며, 해조류로 우뭇가사리 등이 있고, 인근의 어민들의 어업형태는 꼬막 등 패류의 채취나 종패를 뿌려 일정기간 양성하여 수확하는 양식업, 육상부에서 폐염전 등을 활용한 전어나 새우 등을 양식하는 양식업, 수산물을 직접 손이나 간단한 도구를 이용하여 잡는 맨손 어업 형태가 주를 이루고 있는 것으로 나타나고 있다. 이와 같이 국내외적으로 중요할 뿐만 아니라 인근의 어민들의 생계에도 지대한 영향을 미치고 있는 순천만의 습지는 뻘층이 깊고, 분해성 미생물이 다양하게 서식하여 유기물 분해능력이 뛰어나며, 유기영양분이 풍부하여 우리나라에서 가장 질이 좋은 습지로 평가되고 있으나, 순천시 등 순천만 인근에 거주하고 있는 인간의 활동에 따른 간섭에 많은 영향을 받고 있으며, 이에 따라 끊임없는 생태환경이 변화하고 있어서 순천만의 효율적인 보전 및 지속가능한 이용을 위해서는 생태계에서 가장 기본적인 요소인 수 저질 환경의 지속적이고 체계적인 조사 및 관리가 필요하다. 한편, 오염물질의 70% 이상은 하천이나 강을 통해서 해역으로 유입된다고 알려져 있기 때문에 생태계의 보고(寶庫)라고 알려진 순천만의 지속적인 보존 및 관리를 위해서는 유입수계 하천의 수질현황 및 오염물질의 주요 배출원을 파악하고, 이에 대한 저감대책을 수립할 필요가 있다. 따라서 본 연구는 순천만의 수저질 특성과 여기에 유입되는 하천의 수질환경 현황 및 오염원을 파악함으로써 순천만의 보전을 위한 효율적 관리방안을 제시하는 것을 목적으로 수행되었다. 연구의 결과에 따르면, 순천만의 수질평가지수에 의한 등급(WQI)은 III등급으로 나타나고 있으며, 득량만, 광양만 등에 비해 비교적 높은 유기물 및 T-N, T-P의 농도 분포를 보이고 있는 것으로 조사되었다. 이는 순천만에 유입되는 하수종말처리장의 방류수와 도시하수가 유입되어 그대로 방류되고 있는 해룡천 및 연안에 위치한 어촌으로부터 직접 방류되고 있는 일부 정화조 유출수 등, 다양한 원인에 의한 것으로 판단되며 이들의 관리가 부실할 경우 순천만의 갯벌과 습지의 지속가능한 생태환경유지는 쉽지 않다. 따라서 이를 효율적으로 관리하기 위해서는 순천만 연안의 오염물질 방류를 총량관리로 전환하여 철저히 관리하는 것이 필요할 것으로 판단된다.

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Korea National College of Agriculture and Fisheries in Naver News by Web Crolling : Based on Keyword Analysis and Semantic Network Analysis (웹 크롤링에 의한 네이버 뉴스에서의 한국농수산대학 - 키워드 분석과 의미연결망분석 -)

  • Joo, J.S.;Lee, S.Y.;Kim, S.H.;Park, N.B.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.23 no.2
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    • pp.71-86
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    • 2021
  • This study was conducted to find information on the university's image from words related to 'Korea National College of Agriculture and Fisheries (KNCAF)' in Naver News. For this purpose, word frequency analysis, TF-IDF evaluation and semantic network analysis were performed using web crawling technology. In word frequency analysis, 'agriculture', 'education', 'support', 'farmer', 'youth', 'university', 'business', 'rural', 'CEO' were important words. In the TF-IDF evaluation, the key words were 'farmer', 'dron', 'agricultural and livestock food department', 'Jeonbuk', 'young farmer', 'agriculture', 'Chonju', 'university', 'device', 'spreading'. In the semantic network analysis, the Bigrams showed high correlations in the order of 'youth' - 'farmer', 'digital' - 'agriculture', 'farming' - 'settlement', 'agriculture' - 'rural', 'digital' - 'turnover'. As a result of evaluating the importance of keywords as five central index, 'agriculture' ranked first. And the keywords in the second place of the centrality index were 'farmers' (Cc, Cb), 'education' (Cd, Cp) and 'future' (Ce). The sperman's rank correlation coefficient by centrality index showed the most similar rank between Degree centrality and Pagerank centrality. The KNCAF articles of Naver News were used as important words such as 'agriculture', 'education', 'support', 'farmer', 'youth' in terms of word frequency. However, in the evaluation including document frequency, the words such as 'farmer', 'dron', 'Ministry of Agriculture, Food and Rural Affairs', 'Jeonbuk', and 'young farmers' were found to be key words. The centrality analysis considering the network connectivity between words was suitable for evaluation by Cd and Cp. And the words with strong centrality were 'agriculture', 'education', 'future', 'farmer', 'digital', 'support', 'utilization'.

Soil Classification of Paddy Soils by Soil Taxonomy (미국신분류법(美國新分類法)에 의(依)한 답토양의 분류(分類)에 관한 연구)

  • Joo, Yeong-Hee;Shin, Yong-Hwa
    • Korean Journal of Soil Science and Fertilizer
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    • v.11 no.2
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    • pp.97-104
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    • 1979
  • According to Soil Taxonomy which has been developed over the past 20 years in the soil conservation service of the U. S. D. A, Soils in Korea are classified. This system is well suited for the classification of the most of soils. But paddy field soils have some difficulties in classification because Soil Taxonomy states no proposals have yet been developed for classifying artificially irrigated soils. This paper discusses some problems in the application of Taxonomy and suggestes the classification of paddy field soils in Korea. Following is the summary of the paper. 1. Anthro aquic, Aquic Udipsamments : The top soils of these soils are saturated with irrigated water at some time of year and have mottles of low chroma(2 or less) more than 50cm of the soil surface. (Ex. Sadu, Geumcheon series) 2. Anthroaquic Udipsamments : These sails are like Anthroaquic, Aquic Udipsamments except for the mottles of low chroma within 50cm of the soil surface. (Ex. Baegsu series) 3. Halic Psammaquents : These soils contain enough salts as distributed in the profile that they interfere with the growth of most crop plants and located on the coastal dunes. The water table fluctuates with the tides. (Ex. Nagcheon series) 4. Anthroaquic, Aquic Udifluvents : They have some mottles that have chroma of 2 or less in more than 50cm of the surface. The upper horizon is saturated with irrigated water at sometime. (Ex. Maryeong series) 5. Anthro aquic Udifluvents : These soils are saturated with irrigated water at some time of year and have mottles of low chroma(2 or less) within 50cm of the surface soils. (Ex. Haenggog series) 6. Fluventic Haplaquepts : These soils have a content of organic carbon that decreases irregularly with depth and do not have an argillic horizon in any part of the pedon. Since ground water occur on the surface or near the surface, they are dominantly gray soils in a thick mineral regolith. (Ex Baeggu, Hagseong series) 7. Fluventic Thapto-Histic Haplaquepts : These soils have a buried organic matter layer and the upper boundary is within 1m of the surface. Other properties are same as Fluventic Haplaquepts. (Ex. Gongdeog, Seotan series) 8. Fluventic Aeric Haplaquepts : These soils have a horizon that has chroma too high for Fluventic Haplaquepts. The higher chroma is thought to indicate either a shorter period of saturation of the whole soils with water or some what deeper ground water than in the Fluventic Haplaquepts. The correlation of color with soil drainage classes is imperfect. (Ex. Mangyeong, Jeonbug series) 9. Fluventic Thapto-Histic Aeric Haplaquepts : These soils are similar to Fluventic Thapto Histic Haplaquepts except for the deeper ground water. (Ex. Bongnam series) 10. Fluventic Aeric Sulfic Haplaquepts : These soils are similar to Fluventic Aeric Haplaquepts except for the yellow mottles and low pH (<4.0) in some part between 50 and 150cm of the surface. (Ex. Deunggu series) 11. Fluventic Sulfaquepts : These soils are extremely acid and toxic to most plant. Their horizons are mostly dark gray and have yellow mottles of iron sulfate with in 50cm of the soil surface. They occur mainly in coastal marshes near the mouth of rivers. (Ex. Bongrim, Haecheog series) 12. Fluventic Aeric Sulfaquepts : They have a horizon that has chroma too high for Fluventic Sulfaquepts. Other properties are same as Fluventic Sulfaquepts. (Ex. Gimhae series) 13. Anthroaquic Fluvaquentic Eutrochrepts : These soils have mottles of low chroma in more than 50cm of the surface due to irrigated water. The base saturation is 60 percent or more in some subhroizon that is between depth of 25 and 75cm below the surface. (Ex. Jangyu, Chilgog series) 14. Anthroaquic Dystric Fluventic Eutrochrepts : These soils are similar to Anthroaquic Fluvaquentic Eutrochrepts except for the low chroma within 50cm of the surface. (Ex. Weolgog, Gyeongsan series) 15. Anthroaquic Fluventic Dystrochrepts : These soils have mottles that have chroma of 2 or less within 50cm of the soil surface due to artificial irrigation. They have lower base saturation (<60 percert) in all subhorizons between depths of 25 and 75cm below the soil surface. (Ex. Gocheon, Bigog series) 16. Anthro aquic Eutrandepts : These soils are similar to Anthroaquic Dystric Fluventic Eutrochrepts except for lower bulk density in the horizon. (Ex. Daejeong series) 17. Anthroaquic Hapludalfs : These soils' have a surface that is saturated with irrigated water at some time and have chroma of 2 or less in the matrix and higher chroma of mottles within 50cm of the surface. (Ex. Hwadong, Yongsu series) 18. Anthro aquic, Aquic Hapludalfs : These soils are similar to Anthro aquic Hapludalfs except for the matrix that has chroma 2 or less and higher chroma of mottles in more than 50cm of the surface. (Ex. Geugrag, Deogpyeong se ries)

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A study on the second edition of Koryo Dae-Jang-Mock-Lock (고려재조대장목록고)

  • Jeong Pil-mo
    • Journal of the Korean Society for Library and Information Science
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    • v.17
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    • pp.11-47
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    • 1989
  • This study intends to examine the background and the procedure of the carving of the tablets of the second edition of Dae-Jang-Mock­Lock(재조대장목록). the time and the route of the moving of the tablets. into Haein-sa, and the contents and the system of it. This study is mainly based on the second edition of Dae-Jang-Mock-Lock. But the other closely related materials such as restored first. edition of the Dae- Jang-Mock-Lock, Koryo Sin-Jo-Dae-Jang-Byeol-Lock (고려신조대장교정별록). Kae-Won-Seok-Kyo-Lock (개원석교록). Sok-Kae­Won-Seok-Kyo-Lock (속개원석교록). Jeong-Won-Sin-Jeong-Seok-Kyo­Lock(정원신정석교록), Sok-Jeong-Won-Seok-Kyo-Lock(속정원석교록), Dea-Jung-Sang-Bu-Beob-Bo-Lock(대중상부법보록), and Kyeong-Woo-Sin-Su-Beob-Bo-Lock(경우신수법보록), are also analysed and closely examined. The results of this study can be summarized as follows: 1. The second edition of Tripitaka Koreana(고려대장경) was carved for the purpose of defending the country from Mongolia with the power of Buddhism, after the tablets of the first edition in Buin-sa(부이사) was destroyed by fire. 2. In 1236. Dae-Jang-Do-Gam(대장도감) was established, and the preparation for the recarving of the tablets such as comparison between the content, of the first edition of Tripitalk Koreana, Gal-Bo-Chik-Pan-Dae­Jang-Kyeong and Kitan Dae- Jang-Kyeong, transcription of the original copy and the preparation of the wood, etc. was started. 3. In 1237 after the announcement of Dae-Jang-Gyeong-Gak-Pan-Gun­Sin-Gi-Go-Mun(대장경핵판군신석고문), the carving was started on a full scale. And seven years later (1243), Bun-Sa-Dae-Jang-Do-Gam(분사대장도감) was established in the area of the South to expand and hasten the work. And a large number of the tablets were carved in there. 4. It took 16 years to carve the main text and the supplements of the second edition of Tripitaka Koreana, the main text being carved from 1237 to 1248 and the supplement from 1244 to 1251. 5. It can be supposed that the tablets of the second edition of Tripitaka Koreana, stored in Seon-Won-Sa(선원사), Kang-Wha(강화), for about 140 years, was moved to Ji-Cheon-Sa(지천사), Yong-San(용산), and to Hae-In-Sa(해인사) again, through the west and the south sea and Jang-Gyeong-Po(장경포), Go-Ryeong(고령), in the autumn of the same year. 6. The second edition of Tripitaka Koreana was carved mainly based on the first edition, comparing with Gae-Bo-Chik-Pan-Dae-Jang-Kyeong(개보판대장경) and Kitan Dae-Jang-Kyeong(계단대장경). And the second edition of Dae-Jang-Mock-Lock also compiled mainly based on the first edition with the reference to Kae-Won-Seok-Kyo-Lock and Sok-Jeong-Won-Seok-Kyo-Lock. 7. Comparing with the first edition of Dae-Jang-Mock-Lock, in the second edition 7 items of 9 volumes of Kitan text such as Weol-Deung­Sam-Mae-Gyeong-Ron(월증삼매경론) are added and 3 items of 60 volumes such as Dae-Jong-Ji-Hyeon-Mun-Ron(대종지현문논) are substituted into others from Cheon chest(천함) to Kaeng chest(경함), and 92 items of 601 volumes such as Beob-Won-Ju-Rim-Jeon(법원주임전) are added after Kaeng chest. And 4 items of 50 volumes such as Yuk-Ja-Sin-Ju-Wang-Kyeong(육자신주왕경) are ommitted in the second edition. 8. Comparing with Kae-Won-Seok-Kyo-Lock, Cheon chest to Young chest (영함) of the second edition is compiled according to Ib-Jang-Lock(입장록) of Kae-Won-Seok-Kyo-Lock. But 15 items of 43 vol­umes such as Bul-Seol-Ban-Ju-Sam-Mae-Kyeong(불설반주삼매경) are ;added and 7 items of 35 volumes such as Dae-Bang-Deung-Dae-Jib-Il­Jang-Kyeong(대방등대집일장경) are ommitted. 9. Comparing with Sok-Jeong-Won-Seok-Kyo-Lock, 3 items of the 47 volumes (or 49 volumes) are ommitted and 4 items of 96 volumes are ;added in Caek chest(책함) to Mil chest(밀함) of the second edition. But the items are arranged in the same order. 10. Comparing with Dae- Jung-Sang-Bo-Beob-Bo-Lock, the arrangement of the second edition is entirely different from it. But 170 items of 329 volumes are also included in Doo chest(두함) to Kyeong chest(경함) of the second edition, and 53 items of 125 volumes in Jun chest(존함) to Jeong chest(정함). And 10 items of 108 volumes in the last part of Dae-Jung-Sang-Bo-Beob-Bo-Lock are ommitted and 3 items of 131 volumes such as Beob-Won-Ju-Rim-Jeon(법원주임전) are added in the second edition. 11. Comparing with Kyeong-Woo-Sin-Su-Beob-Bo-Lock, all of the items (21 items of 161 volumes) are included in the second edition without ;any classificatory system. And 22 items of 172 volumes in the Seong­Hyeon-Jib-Jeon(성현집전) part such as Myo-Gak-Bi-Cheon(묘각비전) are ommitted. 12. The last part of the second edition, Joo chest(주함) to Dong chest (동함), includes 14 items of 237 volumes. But these items cannot be found in any other former Buddhist catalog. So it might be supposed as the Kitan texts. 13. Besides including almost all items in Kae-Won-Seok-Kyo-Lock and all items in Sok-Jeong-Won-Seok-Kyo-Lock, Dae-Jung-Sang-Bo­Beob-Bo-Lock, and Kyeong-Woo-Sin-Su-Beob-Bo-Lock, the second edition of Dae-Jang-Mock-Lock includes more items, at least 20 items of about 300 volumes of Kitan Tripitaka and 15 items of 43 volumes of traditional Korean Tripitake that cannot be found any others. Therefore, Tripitaka Koreana can be said as a comprehensive Tripitaka covering all items of Tripitakas translated in Chinese character.

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Air Pollution and Its Effects on E.N.T. Field (대기오염과 이비인후과)

  • 박인용
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1972.03a
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    • pp.6-7
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    • 1972
  • The air pollutants can be classified into the irritant gas and the asphixation gas, and the irritant gas is closely related to the otorhinolaryngological diseases. The common irritant gases are nitrogen oxides, sulfur oxides, hydrogen carbon compounds, and the potent and irritating PAN (peroxy acyl nitrate) which is secondarily liberated from photosynthesis. Those gases adhers to the mucous membrane to result in ulceration and secondary infection due to their potent oxidizing power. 1. Sulfur dioxide gas Sulfur dioxide gas has the typical characteristics of the air pollutants. Because of its high solubility it gets easily absorbed in the respiratory tract, when the symptoms and signs by irritation become manifested initially and later the resistance in the respiratory tract brings central about pulmonary edema and respiratory paralysis of origin. Chronic exposure to the gas leads to rhinitis, pharyngitis, laryngitis, and olfactory or gustatory disturbances. 2. Carbon monoxide Toxicity of carbon monoxide is due to its deprivation of the oxygen carrying capacity of the hemoglobin. The degree of the carbon monoxide intoxication varies according to its concentration and the duration of inhalation. It starts with headache, vertigo, nausea, vomiting and tinnitus, which can progress to respiratory difficulty, muscular laxity, syncope, and coma leading to death. 3. Nitrogen dioxide Nitrogen dioxide causes respiratory disturbances by formation of methemoglobin. In acute poisoning, it can cause pulmonary congestion, pulmonary edema, bronchitis, and pneumonia due to its strong irritation on the eyes and the nose. In chronic poisoning, it causes chronic pulmonary fibrosis and pulmonary edema. 4. Ozone It has offending irritating odor, and causes dryness of na sopharyngolaryngeal mucosa, headache and depressed pulmonary function which may eventually lead to pulmonary congestion or edema. 5. Smog The most outstanding incident of the smog occurred in London from December 5 through 8, 1952, because of which the mortality of the respiratory diseases increased fourfold. The smog was thought to be due to the smoke produced by incomplete combustion and its byproduct the sulfur oxides, and the dust was thought to play the secondary role. In new sense, hazardous is the photochemical smog which is produced by combination of light energy and the hydrocarbons and oxidant in the air. The Yonsei University Institute for Environmental :pollution Research launched a project to determine the relationship between the pollution and the medical, ophthalmological and rhinopharyngological disorders. The students (469) of the "S" Technical School in the most heavily polluted area in Pusan (Uham Dong district) were compared with those (345) of "K" High School in the less polluted area. The investigated group had those with subjective symptoms twice as much as the control group, 22.6% (106) in investigated group and 11.3% (39) in the control group. Among those symptomatic students of the investigated group. There were 29 with respiratory symptoms (29%), 22 with eye symptoms (21%), 50 with stuffy nose and rhinorrhea (47%), and 5 with sore thorat (5%), which revealed that more than half the students (52%) had subjective symptoms of the rhinopharyngological aspects. Physical examination revealed that the investigated group had more number of students with signs than those of the control group by 10%, 180 (38.4%) versus 99 (28.8%). Among the preceding 180 students of the investigated group, there were 8 with eye diseases (44%), 1 with respiratory disease (0.6%), 97 with rhinitis (54%), and 74 with pharyngotonsillitis (41%) which means that 95% of them had rharygoical diseases. The preceding data revealed that the otolaryngological diseases are conspicuously outnumbered in the heavily polluted area, and that there must be very close relationship between the air pollution and the otolaryngological diseases, and the anti-pollution measure is urgently needed.

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Effect of Pressure Rise Time on Tidal Volume and Gas Exchange During Pressure Control Ventilation (압력조절환기법에서 압력상승시간(Pressure Rise Time)이 흡기 일환기량 및 가스교환에 미치는 영향)

  • Jeoung, Byung-O;Koh, Youn-Suck;Shim, Tae-Sun;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong;Lim, Chae-Man
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.5
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    • pp.766-772
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    • 2000
  • Background : Pressure rise time (PRT) is the time in which the ventilator aclieves the set airway pressure in pressure-targeted modes, such as pressure control ventilation (PCV). With varying PRT, in principle, the peak inspiratory flow rate of the ventilator also varies. And if PRT is set to a shorter duration, the effective duration of target pressure level would be prolonged, which in turn would increase inspiratory tidal volume(Vti) and mean airway pressure (Pmean). We also postulated that the increase in Vti with shortening of PRT may relate inversely to the patients' basal airway resistance. Methods : In 13 paralyzed patients on PCV (pressure control 18$\pm$9.5 cm $H_2O$ $FIO_2\;0.6\pm0.3$, PEEP 5$\pm$3 cm $H_2O$, f 20/min, I : E1 : 2) with Servo 300 (Siemens-Elema, Solna, Sweden) from various causes of respiratory failure, PRT of 10 %, 5 % and 0 % were randomly applied. At 30 min of each PRT trial, peak inspiratory flow (PIF, L/sec), Vti (ml), Pmean (cm $H_2O$) and ABGA were determined. Results : At PRT 10%, 5%, and 0%, PIF were 0.69$\pm$0.13, 0.77$\pm$0.19, 0.83$\pm$0.22, respectively (p<0.001). Vti were 425$\pm$94, 439$\pm$101, 456$\pm$106, respectively (p<0.001), and Pmean were 11.2$\pm$3.7, 12.0$\pm$3.7, 12.5$\pm$3.8, respectively (p<0.001). pH were 7.40$\pm$0.08, 7.40$\pm$0.92, 7.41$\pm$0.96, respectively (p=0.00) ; $PaCO_2$ (mm Hg) were 47.4$\pm$15.8, 47.2 $\pm$15.7, 44.6$\pm$16.2, respectively (p=0.004) ; $PAO_2-PaO_2$ (mm Hg) were 220$\pm$98, 224$\pm$95, 227$\pm$94, respectively (p=0.004) ; and $V_n/V_T$ as determined by ($PaCO_2-P_E-CO_2$)/$PaCO_2$ were 0.67$\pm$0.07, 0.67$\pm$0.08, 0.66$\pm$0.08, respectively (p=0.007). The correlation between airway resistance and change of Vti from PRT 10% to 0% were r= -0.243 (p=0.498). Conclusion : Shortening of pressure rise timee during PCV was associated with increased tidal volume, increased mean airway pressure and lower $PaCO_2$.

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Determination of optimum fertilizer rates for barley reflecting the effect of soil and climate on the response to NPK fertilizers (기상(氣象) 및 토양조건(土壤條件)으로 본 대맥(大麥)의 NPK 시비적량결정(施肥適量決定))

  • Park, Nae Joung;Lee, Chun Soo;Ryu, In Soo;Park, Chun Sur
    • Korean Journal of Soil Science and Fertilizer
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    • v.7 no.3
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    • pp.177-184
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    • 1974
  • An attempt was made to determine simple and the most reasonable fertilizer recommendation for barley utilizing the present knowledge about the effect of soil and climatic factors on barley response to NPK fertilizer in Korea and establishing the critical contents of available nutrients in soils. The results were summarized as follows. 1. The relationships between relative yields or fertilizers rates for maximum yields from quadratic response curves and contents of organic matter, available $P_2O_5$, exchangeable K in soils were examined. The trend was more prospective with relative yields because of smaller variation than with fertilizer rates. 2. Since the relationship between N relative yields and organic matter contents in soils was almost linear over the practical range, it was difficult to determine the critical content for nitrogen response by quadrant methods. However, 2.6%, country average of organic matter content in upland soils was recommended as the critical point. 3. There showed a trend that average optimum nitrogen rater was higher in heavy texture soils, colder regions. 4. The critical $P_2O_5$ contents in soil were 96 or 118 ppm in two different years, which were very close to the country average, 114 ppm of $P_2O_5$ contents in upland soils. The critical K content in soil was 0.32 me/100g, which was exactly coincident to the country average of exchangeable K in upland soils. 5. According to the contents of avaiiable $P_2O_5$ and exchangeable K, several ranges were established for the purpose of convenience in fertilizer recommendation, that is, very low, Low, Medium, High and very High. 6. More phosphate was recommended in the northern region, clayey soils, and paddy soils, whereas less in the southern region and sandy soils. More potash was recommended in the northern region and sandy soils, whereas less in the southern region and clayey soils. 7. The lower the PH, the more fertilizers were recommended. However, liming was considered to be more effective than increas in amount of fertilizers.

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