• Title/Summary/Keyword: trend analysis

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The Role of Radiotherapy for Carcinomas of the Gall Bladder and Extrahepatic Biliary Duct: Retrospective Analysis (담낭 및 간외담도계 악성종양의 방사선치료결과)

  • Jeong Hyeon Ju;Lee Hyun Ju;Yang Kwang Mo;Suh Hyun Suk;Kim Re Hwe;Kim Sung Rok;Kim Hong Ryong
    • Radiation Oncology Journal
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    • v.16 no.1
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    • pp.43-49
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    • 1998
  • Purpose : Carcinomas arising in the gall bladder(GB) or extrahepatic biliary ducts are uncommon and generally have a poor prognosis. The overall 5-year survival rates are less than $10\%$. Early experiences with the external radiation therapy demonstrated a good palliation with occasional long-term survival. The present report describes our experience over the past decade with irradiation of primary carcinomas of the gallbladder and extrahepatic biliary duct. Materials and Methods : From Feb. 1984 to Nov. 1995, thirty-three patients with carcinoma of the GB and extrahepatic biliary duct were treated with external beam radiotherapy with curative intent at our institution. All patients were treated with 4-MV linear accelerator and radiation dose ranged from 31.44Gy to 54.87Gy(median 44.25Gy), and three Patients received additional intraluminal brachytherapy(range, 25Gy to 30Gy). Twenty-seven Patients received postoperative radiation. Among 27 patients, Sixteen patients underwent radical operation with curative aim and the rest of the patients either had bypass surgery or biopsy alone. In seventeen patients, adjuvant chemotherapy was used and eleven patients were treated with 5-FU, mitomycin and leucovorin. Results : Median follow up period was 8.5 months(range 2-97 months). The overall 2-year and 5-year survival rates in all patients were $29.9\%$ and $13.3\%$ respectively. In patients with GB and extrahepatic biliary duct carcinomas, the 2-year survival rates were $34.5\%$ and $27.8\%$ respectively. Patients who underwent radical operation showed better 2-year survival rates than those who underwent palliative operation($43.8\%\;vs.\;20.7\%$), albeit statistically insignificant(p>0.05). The 2-year survival rates in Stage I and II were higher than in Stage III and IV with statistical significance(p<0.05). Patients with good performance status in the beginning showed significantly better survival rates than those with worse status(p<0.05). The 2-year survival rates in combined chemotherapy group and radiation group were $40.5\%$ and $22.0\%$ respectively. There was no statistical differences in two groups (p>0.05). Conclusion : The survival of patients with relatively lower stage and/or initial good performance was significantly superior to that of others. We found an statistically insignificant trend toward better survival in patients with radical operation and/or chemotherapy, More radical treatment strategies, such as total resection with intensive radiation and/or chemotherapy may offer a better chance for cure in selective patients with carcinoma of gall bladder and extrahepatic biliary ducts.

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Understanding User Motivations and Behavioral Process in Creating Video UGC: Focus on Theory of Implementation Intentions (Video UGC 제작 동기와 행위 과정에 관한 이해: 구현의도이론 (Theory of Implementation Intentions)의 적용을 중심으로)

  • Kim, Hyung-Jin;Song, Se-Min;Lee, Ho-Geun
    • Asia pacific journal of information systems
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    • v.19 no.4
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    • pp.125-148
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    • 2009
  • UGC(User Generated Contents) is emerging as the center of e-business in the web 2.0 era. The trend reflects changing roles of users in production and consumption of contents on websites and helps us to understand new strategies of websites such as web portals and social network websites. Nowadays, we consume contents created by other non-professional users for both utilitarian (e.g., knowledge) and hedonic values (e.g., fun). Also, contents produced by ourselves (e.g., photo, video) are posted on websites so that our friends, family, and even the public can consume those contents. This means that non-professionals, who used to be passive audience in the past, are now creating contents and share their UGCs with others in the Web. Accessible media, tools, and applications have also reduced difficulty and complexity in the process of creating contents. Realizing that users create plenty of materials which are very interesting to other people, media companies (i.e., web portals and social networking websites) are adjusting their strategies and business models accordingly. Increased demand of UGC may lead to website visits which are the source of benefits from advertising. Therefore, they put more efforts into making their websites open platforms where UGCs can be created and shared among users without technical and methodological difficulties. Many websites have increasingly adopted new technologies such as RSS and openAPI. Some have even changed the structure of web pages so that UGC can be seen several times to more visitors. This mainstream of UGCs on websites indicates that acquiring more UGCs and supporting participating users have become important things to media companies. Although those companies need to understand why general users have shown increasing interest in creating and posting contents and what is important to them in the process of productions, few research results exist in this area to address these issues. Also, behavioral process in creating video UGCs has not been explored enough for the public to fully understand it. With a solid theoretical background (i.e., theory of implementation intentions), parts of our proposed research model mirror the process of user behaviors in creating video contents, which consist of intention to upload, intention to edit, edit, and upload. In addition, in order to explain how those behavioral intentions are developed, we investigated influences of antecedents from three motivational perspectives (i.e., intrinsic, editing software-oriented, and website's network effect-oriented). First, from the intrinsic motivation perspective, we studied the roles of self-expression, enjoyment, and social attention in forming intention to edit with preferred editing software or in forming intention to upload video contents to preferred websites. Second, we explored the roles of editing software for non-professionals to edit video contents, in terms of how it makes production process easier and how it is useful in the process. Finally, from the website characteristic-oriented perspective, we investigated the role of a website's network externality as an antecedent of users' intention to upload to preferred websites. The rationale is that posting UGCs on websites are basically social-oriented behaviors; thus, users prefer a website with the high level of network externality for contents uploading. This study adopted a longitudinal research design; we emailed recipients twice with different questionnaires. Guided by invitation email including a link to web survey page, respondents answered most of questions except edit and upload at the first survey. They were asked to provide information about UGC editing software they mainly used and preferred website to upload edited contents, and then asked to answer related questions. For example, before answering questions regarding network externality, they individually had to declare the name of the website to which they would be willing to upload. At the end of the first survey, we asked if they agreed to participate in the corresponding survey in a month. During twenty days, 333 complete responses were gathered in the first survey. One month later, we emailed those recipients to ask for participation in the second survey. 185 of the 333 recipients (about 56 percentages) answered in the second survey. Personalized questionnaires were provided for them to remind the names of editing software and website that they reported in the first survey. They answered the degree of editing with the software and the degree of uploading video contents to the website for the past one month. To all recipients of the two surveys, exchange tickets for books (about 5,000~10,000 Korean Won) were provided according to the frequency of participations. PLS analysis shows that user behaviors in creating video contents are well explained by the theory of implementation intentions. In fact, intention to upload significantly influences intention to edit in the process of accomplishing the goal behavior, upload. These relationships show the behavioral process that has been unclear in users' creating video contents for uploading and also highlight important roles of editing in the process. Regarding the intrinsic motivations, the results illustrated that users are likely to edit their own video contents in order to express their own intrinsic traits such as thoughts and feelings. Also, their intention to upload contents in preferred website is formed because they want to attract much attention from others through contents reflecting themselves. This result well corresponds to the roles of the website characteristic, namely, network externality. Based on the PLS results, the network effect of a website has significant influence on users' intention to upload to the preferred website. This indicates that users with social attention motivations are likely to upload their video UGCs to a website whose network size is big enough to realize their motivations easily. Finally, regarding editing software characteristic-oriented motivations, making exclusively-provided editing software more user-friendly (i.e., easy of use, usefulness) plays an important role in leading to users' intention to edit. Our research contributes to both academic scholars and professionals. For researchers, our results show that the theory of implementation intentions is well applied to the video UGC context and very useful to explain the relationship between implementation intentions and goal behaviors. With the theory, this study theoretically and empirically confirmed that editing is a different and important behavior from uploading behavior, and we tested the behavioral process of ordinary users in creating video UGCs, focusing on significant motivational factors in each step. In addition, parts of our research model are also rooted in the solid theoretical background such as the technology acceptance model and the theory of network externality to explain the effects of UGC-related motivations. For practitioners, our results suggest that media companies need to restructure their websites so that users' needs for social interaction through UGC (e.g., self-expression, social attention) are well met. Also, we emphasize strategic importance of the network size of websites in leading non-professionals to upload video contents to the websites. Those websites need to find a way to utilize the network effects for acquiring more UGCs. Finally, we suggest that some ways to improve editing software be considered as a way to increase edit behavior which is a very important process leading to UGC uploading.

A Comparison of the Designation Characteristics of Korean Scenic Sites Policies and National Park System in the United States (국내 명승 정책과 미국 국립공원 시스템의 지정 특성 비교)

  • Lee, Won-Ho;Kim, Dong-Hyun;Janet, R. Balsom
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.3
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    • pp.25-34
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    • 2020
  • This study examined the definition and major values, the designated procedures and types, and the designation trend in Korean scenic sites and national parks in the United States. Based on this, the analysis of the characteristics of the designation of the two natural heritages. The results are as follows; First, Scenic Sites has characteristics of complex heritage that includes academic, historical, and humanities values on the basis of landscape. As a natural heritage based on public nature, the U.S. National Park aims to contribute to the people's natural heritage and satisfy both ecological and historical values through the protection of the landscape. Second, the designation of a scenic sites are decided through deliberation by the Cultural Heritage Committee after the request of the owner, manager, or local government or by the authority of the head of the Cultural Heritage Administration. The designated survey is divided into basic resource surveys and resource surveys by type. Since the initial designation of the Sogeumgang Mountain in Cheonghakdong, Myeongju in 1970, the number of designated scenic sites was low until the 2000s, but the number of designated scenic sites has increased rapidly since 2006 due to the policy to promote the scenic site, and the proportion of natural and historical and cultural scenic sites has been balanced. The designation of the U.S. national park is decided by the Congress or the president, and the National Park Service makes a series of decisions on whether to conduct a special resource study of provisional resources through a preliminary inspection survey, whether to satisfy the criteria for designation of national parks based on the results of special resource research, and to prioritize them. The U.S. National Parks have been expanded not only by Congress but also by the president's empowerment to designate them as national monuments. With the integrated operation of the National Park Service, the number of designated cases increased as the national park included the heritage sites under the control of various ministries. In addition, a number of historical areas were designated by the enactment of the Historical Site Act, and recreational areas were designated to provide leisure space and classified and managed in a total of 18 units. Third, the comparison of the designation characteristics of the two heritage properties confirmed that the designation of natural heritage with complex value, the classification of types according to complementary designation system and resource characteristics, the establishment of the competent ministry and the balancing of the heritage according to the designation policy. The two heritages had the characteristics of complex natural heritages that met ecological, historical and academic values at the same time based on landscape and public nature. In addition, both countries have identified a system for deliberating the designation of heritage through a basic resource survey and an in-depth designation survey, and classified each type according to the characteristics of the resource. In addition, the policies for promoting scenic sites in Korea and the integrated operation of the National Park Service in the U.S. influenced the designated aspects of the two heritage sites, balancing natural heritage with historical and cultural heritage. Fourth, the resource types and conservation management methods of Scenic site and National Park were largely related. The natural areas of the U.S. National Park include types of natural monuments in Korea as major resources, and have characteristics similar to natural scenic sites. In addition, historical resources were similar to the criteria for designation of historical and cultural scenic sites in terms of landscape, and the aspects of war and celebrity-related relics were related to the types of historic sites. In terms of conservation management, the natural area of the U.S. national park has a way of keeping the original ecosystem intact, but the Korean natural heritage protection system is likely to be useful for focusing on the resource of viscosity. Meanwhile, historical resources include historical sites and historical and cultural scenic sites in the traditional era, but historical relics in the U.S. National Parks have set a time limit to modern times for war history and celebrity-related relics, and the active provision of entertainment programs based on existing resources was derived as a difference.

Studies on the Mechanical Properties of Weathered Granitic Soil -On the Elements of Shear Strength and Hardness- (화강암질풍화토(花崗岩質風化土)의 역학적(力學的) 성질(性質)에 관(關)한 연구(硏究) -전단강도(剪斷强度)의 영향요소(影響要素)와 견밀도(堅密度)에 대(對)하여-)

  • Cho, Hi Doo
    • Journal of Korean Society of Forest Science
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    • v.66 no.1
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    • pp.16-36
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    • 1984
  • It is very important in forestry to study the shear strength of weathered granitic soil, because the soil covers 66% of our country, and because the majority of land slides have been occured in the soil. In general, the causes of land slide can be classified both the external and internal factors. The external factors are known as vegetations, geography and climate, but internal factors are known as engineering properties originated from parent rocks and weathering. Soil engineering properties are controlled by the skeleton structure, texture, consistency, cohesion, permeability, water content, mineral components, porosity and density etc. of soils. And the effects of these internal factors on sliding down summarize as resistance, shear strength, against silding of soil mass. Shear strength basically depends upon effective stress, kinds of soils, density (void ratio), water content, the structure and arrangement of soil particles, among the properties. But these elements of shear strength work not all alone, but together. The purpose of this thesis is to clarify the characteristics of shear strength and the related elements, such as water content ($w_o$), void ratio($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$), and the interrelationship among related elements in order to decide the dominant element chiefly influencing on shear strength in natural/undisturbed state of weathered granitic soil, in addition to the characteristics of soil hardness of weathered granitic soil and root distribution of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands. For the characteristics of shear strength of weathered granitic soil and the related elements of shear strength, three sites were selected from Kwangju district. The outlines of sampling sites in the district were: average specific gravity, 2.63 ~ 2.79; average natural water content, 24.3 ~ 28.3%; average dry density, $1.31{\sim}1.43g/cm^3$, average void ratio, 0.93 ~ 1.001 ; cohesion, $ 0.2{\sim}0.75kg/cm^2$ ; angle of internal friction, $29^{\circ}{\sim}45^{\circ}$ ; soil texture, SL. The shear strength of the soil in different sites was measured by a direct shear apparatus (type B; shear box size, $62.5{\times}20mm$; ${\sigma}$, $1.434kg/cm^2$; speed, 1/100mm/min.). For the related element analyses, water content was moderated through a series of drainage experiments with 4 levels of drainage period, specific gravity was measured by KS F 308, analysis of particle size distribution, by KS F 2302 and soil samples were dried at $110{\pm}5^{\circ}C$ for more than 12 hours in dry oven. Soil hardness represents physical properties, such as particle size distribution, porosity, bulk density and water content of soil, and test of the hardness by soil hardness tester is the simplest approach and totally indicative method to grasp the mechanical properties of soil. It is important to understand the mechanical properties of soil as well as the chemical in order to realize the fundamental phenomena in the growth and the distribution of tree roots. The writer intended to study the correlation between the soil hardness and the distribution of tree roots of Pinus rigida Mill. planted in 1966 and Pinus rigida ${\times}$ taeda in 199 to 1960 in the denuded forest lands with and after several erosion control works. The soil texture of the sites investigated was SL originated from weathered granitic soil. The former is situated at Py$\ddot{o}$ngchangri, Ky$\ddot{o}$m-my$\ddot{o}$n, Kogs$\ddot{o}$ng-gun, Ch$\ddot{o}$llanam-do (3.63 ha; slope, $17^{\circ}{\sim}41^{\circ}$ soil depth, thin or medium; humidity, dry or optimum; height, 5.66/3.73 ~ 7.63 m; D.B.H., 9.7/8.00 ~ 12.00 cm) and the Latter at changun-long Kwangju-shi (3.50 ha; slope, $12^{\circ}{\sim}23^{\circ}$; soil depth, thin; humidity, dry; height, 10.47/7.3 ~ 12.79 m; D.B.H., 16.94/14.3 ~ 19.4 cm).The sampling areas were 24quadrats ($10m{\times}10m$) in the former area and 12 in the latter expanding from summit to foot. Each sampling trees for hardness test and investigation of root distribution were selected by purposive selection and soil profiles of these trees were made at the downward distance of 50 cm from the trees, at each quadrat. Soil layers of the profile were separated by the distance of 10 cm from the surface (layer I, II, ... ...). Soil hardness was measured with Yamanaka soil hardness tester and indicated as indicated soil hardness at the different soil layers. The distribution of tree root number per unit area in different soil depth was investigated, and the relationship between the soil hardness and the number of tree roots was discussed. The results obtained from the experiments are summarized as follows. 1. Analyses of simple relationship between shear strength and elements of shear strength, water content ($w_o$), void ratio ($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$). 1) Negative correlation coefficients were recognized between shear strength and water content. and shear strength and void ratio. 2) Positive correlation coefficients were recognized between shear strength and dry density. 3) The correlation coefficients between shear strength and specific gravity were not significant. 2. Analyses of partial and multiple correlation coefficients between shear strength and the related elements: 1) From the analyses of the partial correlation coefficients among water content ($x_1$), void ratio ($x_2$), and dry density ($x_3$), the direct effect of the water content on shear strength was the highest, and effect on shear strength was in order of void ratio and dry density. Similar trend was recognized from the results of multiple correlation coefficient analyses. 2) Multiple linear regression equations derived from two independent variables, water content ($x_1$ and dry density ($x_2$) were found to be ineffective in estimating shear strength ($\hat{Y}$). However, the simple linear regression equations with an independent variable, water content (x) were highly efficient to estimate shear strength ($\hat{Y}$) with relatively high fitness. 3. A relationship between soil hardness and the distribution of root number: 1) The soil hardness increased proportionally to the soil depth. Negative correlation coefficients were recognized between indicated soil hardness and the number of tree roots in both plantations. 2) The majority of tree roots of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands distributed at 20 cm deep from the surface. 3) Simple linear regression equations were derived from indicated hardness (x) and the number of tree roots (Y) to estimate root numbers in both plantations.

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A Study on the Classification and Research Trends of Articles in The Korean Journal of Rural Medicine (한국농촌의학회지(韓國農村醫學會誌)에 게재된 연구논문의 분류 및 연구동향)

  • Wee, You-Mee;Kim, Suk-Il;Park, Hyang;Ryu, So-Yeon;Park, Jong;Kim, Ki-Soon
    • Journal of agricultural medicine and community health
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    • v.25 no.2
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    • pp.231-244
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    • 2000
  • Classification and research trends were studied to analyze a total of 240 original articles that have been published in 34 volumes of The Korean Journal of Rural Medicine from 1976 to 1999. The results were as follows: 1. A total of 337 articles were published. Among them, 240(71.2%) articles were classified as original articles. This number has been increasing significantly over the years as the number of the articles was 13 in the 1970s, 73 in the 1980s, and 154 in the 1990s. 2. There were 10 authors in the original articles and 55(22.9%) of them were written by 3 of them. There were five research institutions involved in the articles, and 106(44.2%) of the articles were done by one research group. 3. In the original articles. 24(10.0%) were noted to be done using research funds, and only 6(2.5%) were written in English. 4. In the view of the research styles of the original articles, 115(47.9%) used analytical study, 92(38.3%) used technical study, 21(9.2%) used experimental study, and 6(2.5%) used case reports. In the 1970s, 13(100.0%) articles used technical study, and in the 1980s, 47(64.4%) used technical studies and 19(26.0%) used analytical studies. However, in the 1990s, 96(62.8%) articles used analytical studies and 32(20.9%) used technical studies. The statistical methods most commonly used in the articles were technical statistics, the ${\chi}^2$-test, and the t-test respectively. 5. On the classification into three different research fields, 105(43.8%) articles were classified as health management, 96(40.0%) as disease epidemiology, and 39(16.3%) as rural environment and rural occupational disorders. In the 1970s, 12 (92.3 %) of the articles were on disease epidemiology and 1(7.7%) on health management were published. In the 1980s, 33(45.2%) articles on disease epidemiology, 29(39.7%) on health control, and 11(15.1%) on rural environment and rural occupational disorders were recorded. In the 1990s, however, 75(48.7%) articles were on health control, 51(33.1%) on disease control, and 28(18.2%) on the rural environment and rural occupational disorders. 6. According to the research subjects in each research field, the 39 articles in rural environment and rural occupational disorders were composed of 8(20.5%) articles on pesticide intoxication, 7(17,9%) on farmer's diseases, 7(17.9%) on vinyl-house diseases, and 6(15.4%) on accidents. From a total of 96 articles in disease epidemiology 56(58.3%) articles were on parasites, 16(16.7%) on non-infectious diseases, 12(12.5) on infectious diseases. From 105 articles in health control 25(23.8%) articles were on medical care utilization patterns, 18(17.1%) on the health care delivery system, and 13(12.4%) on maternal and child health. In the analysis of the 10 most prevalent subjects dealt in the above articles, 6(46.2%) articles were on parasites and 4(30.8%) on non-infectious diseases were recorded in the 1970s. In the 1980s, 28(38.4%) were on parasites. 9(12.3%) on the health care system, 7(9.6%) on medical care utilization patterns, 5(6.8%) on maternal and child health, and 4(5.5%) were on pesticide intoxication. In the 1990s, 22(14.3%) articles were on parasites. 18(11.7%) on medical care utilization patterns, 16(10.4%) on senile health, 14(9.1%) on the health care system, 10(6.5%) on infectious diseases, arid 10(6.5%) were on non-infectious diseases. In conclusion, the research activity on rural health has been strengthened in this country because the original articles in The Korean Journal of Rural Medicine have significantly increased in the past 24 years. In the 1970s and 1980s, research on disease epidemiology was most prevalent, but in the 1990s papers on health care were most popular. In addition, the articles on parasites were most frequently published in the 1970s, 1980s, and 1990s, showing that parasitic problem was the main theme in those eras. However, in the 1990s, it was evident that the articles on parasites were decreasing and articles on the subject of medical care utilization patterns and senile health increased. Hereafter it was expected that research on health care would be more common in rural health in Korea.

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The effects of aqueous extracts of plant roots on germination of seeds and growth of seedings (식물근의 추출물질이 종자발아 및 유식물의 생장에 미치는 영향)

  • Chan-Ho Park
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.4 no.1
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    • pp.1-23
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    • 1968
  • This study aimed at contributing to the improvement of cropping systems after finding out the effects of excrements and components of crop root influence on other crops as well as themselves. The following forage crops suitable for our country were selected for the present study. Aqueous extracts of fresh roots, aqueous extracts of rotting roots and aqueous solutions of excrements of red clover, orchard grass and brome grass were studied for the effects influencing the germination and growth of seedlings of red clover, ladino clover, lespedeza, soybean, orchard grass, Italian ryegrass, brome grass, barley, wheat, sorghum, corn and Hog-millet. In view of the possibility that the organic acid might be closely related to the excrements and components of crop root connected with soil sickness, the acid components of three species of roots were analysed by paper chromatography and gas chromatography method. The following results were obtained: 1. Effects of Aqueous Extracts of Fresh Roots : Aqueous extracts of red clover: The extracts inhibited the growth of seedlings of the ladino clover and lespedeza and also inhibited the development of most crops except that of sorghum among the Graminaceae. Aqueous extracts of orchard grass: The extracts promoted the seedlings growth of red clover and soybean, while it inhibited the germination and growth of orchard grass. There were no noticeable effects influencing other crops while it inhibited the growth of barley and Hog-millet. Aqueous extracts of brome grass: There was no effect on Italian ryegrass but there was an inhibiting effect on the other crops. 2. Effects of Aqueous Extracts of Rotting Roots : Aqueous extracts of red clover: The extracts promoted the seedling growth of red clover. But it reflected the inhibiting effects on other crops except sorghum. Aqueous extracts of orchard grass: The extracts promoted the growth of red clover, ladino clover, soybean and sorghun, while it inhibited the germination and rooting of barley and Hog-millet. Aqueous extracts of brome grass: The extracts gave the promotive effects to the growth of red clover, soybean and sorghum, but caused inhibiting effects on orchard grass, brome grass, barley and Hog-millet. 3. Effects of Aqueous Solutions of Excrements : The aqueous solution of excrements of red clover reflected the inhibition effects to the growth of Graminaceae, while the aqueous solutions of excrements of orchard grass and Italian ryegrass caused the promotive effects on the growth of red clover. 4. Results of Organic Acid Analysis : The oxalic acid, citric acid, tartaric acid, malonic acid, malic acid and succinic acid were included in the roots of red clover as unvolatile organic acid, and in the orchard grass and brome grass there were included the oxalic acid, citric acid, tartaric acid and malic acid. And formic acid was confirmed in the red clover, orchard grass and brome grass as volatile organic acid. In consideration of the results mentioned in above the effects of excrements and components of roots found in this studies may be summarized as follows. 1) The red clover generally gave a disadvantageous effect on the Graminaceae. Such trend was considered chiefly caused by the presence of many organic acids, namely oxalic, citric, tartaric, malonic, malic, succinic and formic acid. 2) The orchard grass generally gave an advantageous effect on the Leguminosae. This may be due to a few kinds of organic acid contained in the root, namely oxalic, citric, tartaric, malic and formic acid. Furthermore a certain of promotive materials for growth was noted. 3) As long as the root of brome grass are not rotten, it gave a disadvantageous effect on the Leguminosae and Graminaceae. This may be due to the fact that several unidentified volatile organic acid were also included besides the confirmed organic acid, namely oxalic, citric, tartaric, malic and formic acid. 5. Effects of Components in Roots to the Soil Sickness : 1) It was considered that the cause of alleged red clover's soil sickness did not result from the toxic components of the roots. 2) It was recognized that the toxic components of roots might be the cause of soil sickness in case the orchard grass and brome grass were put into the long-term single cropping. 6. Effects of Rooted Components to the Companion Crops in the Cropping System : a) In case of aqueous extracts of fresh roots and aqueous excrements (Inter cropping and mixed cropping) : 1) Advantageous combinations : Orchard grass->Red clover, Soybean, Italian ryegrass->Red clover, 2) Disadvantageous combinations : Red clover->Ladino clover, Lespedeza, Orchard grass, Italian ryegrass, Fescue Ky-31, Brome grass, Barley, Wheat, Corn and Hog.millet, Orchard grass->Lespedeza, Orchard grass, Barley and Hog-millet, Brome grass->Red clover, Ladino clover, Lespedeza, Soybean, Orchard grass, Brome grass, Barley, Wheat, Sorghum, Corn and Hog-millet, 3) Harmless combinations : Red clover->Red clover, Soybean and Sorghum, Orchard grass->Ladino clover, Italian ryegrass, Brome grass, Wheat, Sorghum and Corn, Brome grass->Italian ryegrass, b) In case of aquecus extracts of rotting roots(After cropping) : 1) Advantageous combinations : Red clover->Red clover and Sorghum, Orchard grass->Red clover, Ladino clover, Soybean, Sorghum, and Corn, Brome grass->Red clover, Soybean and Sorghum, 2) Disadvantageous combinations : Red clover->Lespedeza, Orchard grass, Italian ryegrass, Brome grass, Barley, Wheat, and Hog-millet Orchard grass->Barley and Hog-millet, Brome grass->Orchard grass, Brome grass, Barley and Hog-millet, 3) Harmless combinations : Red clover->Ladino clover, Soybean and Corn, Orchard grass->Lespedeza, Orchard grass, Italian ryegrass, Brome grass and Wheat Brome gass->Ladino clover, Lespedeza, Italian ryegrass and Wheat.

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Problems in the Korean National Family Planning Program (한국가족계획사업(韓國家族計劃事業)의 문제점(問題點))

  • Hong, Jong-Kwan
    • Clinical and Experimental Reproductive Medicine
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    • v.2 no.2
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    • pp.27-36
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    • 1975
  • The success of the family planning program in Korea is reflected in the decrease in the growth rate from 3.0% in 1962 to 2.0% in 1971, and in the decrease in the fertility rate from 43/1,000 in 1960 to 29/1,000 in 1970. However, it would be erroneous to attribute these reductions entirely to the family planning program. Other socio-economic factors, such as the increasing age at marriage and the increasing use of induced abortions, definitely had an impact on the lowered growth and fertility rate. Despite the relative success of the program to data in meeting its goals, there is no room for complacency. Meeting the goal of a further reduction in the population growth rate to 1.3% by 1981 is a much more difficult task than any one faced in the past. Not only must fertility be lowered further, but the size of the target population itself will expand tremendously in the late seventies; due to the post-war baby boom of the 1950's reaching reproductive ages. Furthermore, it is doubtful that the age at marriage will continue to rise as in the past or that the incidence of induced abortion will continue to increase. Consequently, future reductions in fertility will be more dependent on the performance of the national family planning program, with less assistance from these non-program factors. This paper will describe various approaches to help to the solution of these current problems. 1. PRACTICE RATE IN FAMILY PLANNING In 1973, the attitude (approval) and knowledge rates were quite high; 94% and 98% respectively. But a large gap exists between that and the actual practice rate, which is only 3695. Two factors must be considered in attempting to close the KAP-gap. The first is to change social norms, which still favor a larger family, increasing the practice rate cannot be done very quickly. The second point to consider is that the family planning program has not yet reached all the eligible women. A 1973 study determineded that a large portion, 3096 in fact, of all eligible women do not want more children, but are not practicing family planning. Thus, future efforts to help close the KAP-gap must focus attention and services on this important large group of potential acceptors. 2. CONTINUATION RATES Dissatisfaction with the loop and pill has resulted in high discontinuation rates. For example, a 1973 survey revealed that within the first six months initial loop acceptance. nearly 50% were dropouts, and that within the first four months of inital pill acceptance. nearly 50% were dropouts. These discontinuation rates have risen over the past few years. The high rate of discontinuance obviously decreases the contraceptive effectiveness. and has resulted in many unwanted births which is directly related to the increase of induced abortions. In the future, the family planning program must emphasize the improved quality of initial and follow-up services. rather than more quantity, in order to insure higher continuation rates and thus more effective contraceptive protection. 3. INDUCED ABORTION As noted earlier. the use of induced abortions has been increase yearly. For example, in 1960, the average number of abortions was 0.6 abortions per women in the 15-44 age range. By 1970. that had increased to 2 abortions per women. In 1966. 13% of all women between 15-44 had experienced at least one abortion. By 1971, that figure jumped to 28%. In 1973 alone, the total number of abortions was 400,000. Besides the ever incre.sing number of induced abortions, another change has that those who use abortions have shifted since 1965 to include- not. only the middle class, but also rural and low-income women. In the future. in response to the demand for abortion services among rural and low-income w~men, the government must provide and support abortion services for these women as a part of the national family planning program. 4. TARGET SYSTIi:M Since 1962, the nationwide target system has been used to set a target for each method, and the target number of acceptors is then apportioned out to various sub-areas according to the number of eligible couples in each area. Because these targets are set without consideration for demographic factors, particular tastes, prejudices, and previous patterns of acceptance in the area, a high discontinuation rate for all methods and a high wastage rate for the oral pill and condom results. In the future. to alleviate these problems of the methodbased target system. an alternative. such as the weighted-credit system, should be adopted on a nation wide basis. In this system. each contraceptive method is. assigned a specific number of points based upon the couple-years of protection (CYP) provided by the method. and no specific targets for each method are given. 5. INCREASE OF STERILIZA.TION TARGET Two special projects. the hospital-based family planning program and the armed forces program, has greatly contributed to the increasing acceptance in female and male sterilization respectively. From January-September 1974, 28,773 sterilizations were performed. During the same time in 1975, 46,894 were performed; a 63% increase. If this trend continues, by the end of 1975. approximately 70,000 sterilizations will have been performed. Sterilization is a much better method than both the loop and pill, in terms of more effective contraceptive protection and the almost zero dropout rate. In the future, the. family planning program should continue to stress the special programs which make more sterilizations possible. In particular, it should seek to add the laparoscope techniques to facilitate female sterilization acceptance rates. 6. INCREASE NUMBER OF PRIVATE ACCEPTORS Among the current family planning users, approximately 1/3 are in the private sector and thus do not- require government subsidy. The number of private acceptors increases with increasing urbanization and economic growth. To speed this process, the government initiated the special hospital based family planning program which is utilized mostly by the private sector. However, in the future, to further hasten the increase of private acceptors, the government should encourage doctors in private practice to provide family planning services, and provide the contraceptive supplies. This way, those do utilize the private medical system will also be able to receive family planning services and pay for it. Another means of increasing the number of private acceptors, IS to greatly expand the commercial outlets for pills and condoms beyond the existing service points of drugstores, hospitals, and health centers. 7. IE&C PROGRAM The current preferred family size is nearly twice as high as needed to achieve a stable poplation. Also, a strong boy preference hinders a small family size as nearly all couples fuel they must have at least one or more sons. The IE&C program must, in the future, strive to emphasize the values of the small family and equality of the sexes. A second problem for the IE&C program to work. with in the: future is the large group of people who approves family planning, want no more children, but do not practice. The IE&C program must work to motivate these people to accept family planning And finally, for those who already practice, an IE&C program in the future must stress continuation of use. The IE&C campaign, to insure highest effectiveness, should be based on a detailed factor analysis of contraceptive discontinuance. In conclusion, Korea faces a serious unfavorable sociodemographic situation- in the future unless the population growth rate can be curtailed. And in the future, the decrease in fertility will depend solely on the family planning program, as the effect of other socio-economic factors has already been maximumally felt. A second serious factor to consider is the increasing number of eligible women due to the 1950's baby boom. Thus, to meet these challenges, the program target must be increased and the program must improve the effectiveness of its current activities and develop new programs.

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Studies on the selection in soybean breeding. -II. Additional data on heritability, genotypic correlation and selection index- (대두육종에 있어서의 선발에 관한 실험적연구 -속보 : 유전력ㆍ유전상관, 그리고 선발지수의 재검토-)

  • Kwon-Yawl Chang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.3
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    • pp.89-98
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    • 1965
  • The experimental studies were intended to clarify the effects of selection, and also aimed at estimating the heritabilities, the genotypic correlations among some agronomic characters, and at calculating the selection index on some selective characters for the selection of desirable lines, under different climatic conditions. Finally practical implications of these studies, especially on the selection index, were discussed. Twenty-two varieties, determinate growing habit type, were selected at random from the 138 soybean varieties cultivated the year before, were grown in a randomized block design with three replicates at Chinju, Korea, under May and June sowing conditions. The method of estimating heritabilities for the eleven agronomic characters-flowering date, maturity date, stem length, branch numbers per plant, stem diameter, plant weight, pod numbers per plant, grain numbers per plant and 100 grain weight, shown in Table 3, was the variance components procedures in a replicated trial for the varieties. The analysis of covariance was used to obtain the genotypic correlations and phenotypic correlations among the eight characters, and the selection indexes for some agronomic characters were calculated by Robinson's method. The results are summarized as follows: Heritabilities : The experiment on the genotype-environment interaction revealed that in almost all of the characters investigated the interaction was too large to be neglected and materially affected the estimates of various genotypic parameters. The variation in heritability due to the change of environments was larger in the characters of low heritability than in those of high heritability. Heritability values of flowering date, fruiting period (days from flowering to maturity), stem length and 100 grain weight were the highest in both environments, those of yield(grain weight) and other characters were showed the lower values(Table 3). These heritability values showed a decreasing trend with the delayed sowing in the experiments. Further, all calculated heritability values were higher than anticipated. This was expected since these values, which were the broad sense heritability, contain the variance due to dominance and epistasisf in addition to the additive genetic variance. Genotypic correlations : Genotypic correlations were slightly higher than the corresponding phenotypic correlations in both environments, but the variation in values due to the change of environment appeared between grain weight and some other characters, especially an increase between grain weight and flowering date, and the total growing period(Table 6). Genotypic correlations between grain weight and other characters indicated that high seed yield was genetically correlated with late flowering, late maturity, and the other five characters namely branch numbers per plant, stem diameter, plant weight, pod numbers per plant and grain numbers per plant, but not with 100 grain weight of soybeans. Pod numbers and grain numbers per plant were more closely correlated with seed yields than with other characters. Selection index : For the comparison and the use of selection indexes in the selection, two kinds of selection indexes were calculated, the former was called selection index A and the later selection index B as shown in Table 7. Selection index A was calculated by the values of grain weight per plant as the character of yield(character Y), but the other, selection index B, was calculated by the values of pod numbers per plant, instead of grain weight per plant, as the character of yield'(character Y'). These results suggest that selection index technique is useful in soybean breeding. In reality, however, as the selection index varies with population and environment, it must be calculated in each population to which selection is applied and in each environment in which the population is located. In spite of the expected usefulness of selection index technique in soybean breeding, unsolved problems such as the expense, time and labor involved in calculating the selection index remain. For these reasons and from these experimental studies, it was recognized that in the breeding of self-fertilized soybean plants the selection for yield should be based on a more simple selection index such as selection index B of these experiments rather than on the complex selection index such as selection index A. Furthermore, it was realized that the selection index for the selection should be calculated on the basis of the data of some 3-4 agronomic characters-maturity date(X$_1$), branch numbers per plant(X$_2$), stem diameter(X$_3$) and pod numbers per plant etc. It must be noted that it should be successful in selection to select for maturity date(X$_1$) which has high heritability, and the selection index should be calculated easily on the basis of the data of branch numbers per plant(X$_2$), stem diameter(X$_3$) and pod numbers per plant, directly after the harvest before drying and threshing. These characters should be very useful agronomic characters in the selection of Korean soybeans, determinate growing habit type, as they could be measured or counted easily thus saving time and expense in the duration from harvest to drying and threshing, and are affected more in soybean yields than the other agronomic characters.

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A Study on The 'Kao Zheng Pai'(考證派) of The Traditional Medicine of Japan (일본 '고증파(考證派)' 의학에 관한 연구)

  • Park, Hyun-Kuk;Kim, Ki-Wook
    • Journal of Korean Medical classics
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    • v.20 no.4
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    • pp.211-250
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    • 2007
  • 1. The 'Kao Zheng Pai(考證派) comes from the 'Zhe Zhong Pai' and is a school that is influenced by the confucianism of the Qing dynasty. In Japan Inoue Kinga(井上金娥), Yoshida Koton(吉田篁墩) became central members, and the rise of the methodology of historical research(考證學) influenced the members of the 'Zhe Zhong Pai', and the trend of historical research changed from confucianism to medicine, making a school of medicine based on the study of texts and proving that the classics were right. 2. Based on the function of 'Nei Qu Li '(內驅力) the 'Kao Zheng Pai', in the spirit of 'use confucianism as the base', researched letters, meanings and historical origins. Because they were influenced by the methodology of historical research(考證學) of the Qing era, they valued the evidential research of classic texts, and there was even one branch that did only historical research, the 'Rue Xue Kao Zheng Pai'(儒學考證派). Also, the 'Yi Xue Kao Zheng Pai'(醫學考證派) appeared by the influence of Yoshida Kouton and Kariya Ekisai(狩谷掖齋). 3. In the 'Kao Zheng Pai(考證派)'s theories and views the 'Yi Xue Kao Zheng Pai' did not look at medical scriptures like the "Huang Di Nei Jing"("黃帝內經") and did not do research on 'medical' related areas like acupuncture, the meridian and medicinal herbs. Since they were doctors that used medicine, they naturally were based on 'formulas'(方劑) and since their thoughts were based on the historical ideologies, they valued the "Shang Han Ja Bing Lun" which was revered as the 'ancestor of all formulas'(衆方之祖). 4. The lives of the important doctors of the 'Kao Zheng Pai' Meguro Dotaku(目黑道琢) Yamada Seichin(山田正珍), Yamada Kyoko(山田業廣), Mori Ritsi(森立之) Kitamura Naohara(喜多村直寬) are as follows. 1) Meguro Dotaku(目黑道琢 1739${\sim}$1798) was born of lowly descent but, using his intelligence and knowledge, became a professor as a Shi Jing Yi(市井醫) and as a professor for 34 years at Ji Shou Guan mastered the "Huang Di Nei Jing" after giving over 300 lectures. Since his pupil, Isawara Ken taught the Lan Men Wu Zhe(蘭門五哲) and Shibue Chusai, Mori Ritsi(森立之), Okanishi Gentei(岡西玄亭), Kiyokawa Gendoh(淸川玄道) and Yamada Kyoko(山田業廣), Meguro Dotaku is considered the founder of the 'Yi Xue Kao Zheng Pai'. 2) The family of Yamada Seichin(山田正珍 1749${\sim}$1787) had been medical officials in the Makufu(幕府) and the many books that his ancestors had left were the base of his art. Seichin learned from Shan Ben Bei Shan(山本北山), a 'Zhe Zhong Pai' scholar, and put his efforts into learning, teaching and researching the "Shang Han Lun"("傷寒論"). Living in a time between 'Gu Fang Pai'(古方派) member Nakanishi Goretada(中西惟忠) and 'Kao Zheng Pai' member Taki Motohiro(多紀元簡), he wrote 11 books, 2 of which express his thoughts and research clearly, the "Shang Han Lun Ji Cheng"("傷寒論集成") and "Shang Han Kao"("傷寒考"). His comparison of the 'six meridians'(3 yin, 3 yang) between the "Shang Han Lun" and the "Su Wen Re Lun"("素問 熱論) and his acknowledgement of the need and rationality of the concept of Yin-Yang and Deficient-Replete distinguishes him from the other 'Gu Fang Pai'. Also, his dissertation of the need for the concept doesn't use the theories of latter schools but uses the theory of the "Shang Han Lun" itself. He even researched the historical parts, such as terms like 'Shen Nong Chang Bai Cao'(神農嘗百草) and 'Cheng Qi Tang'(承氣湯) 3) The ancestor of Yamada Kyoko(山田業廣) was a court physician, and learned confucianism from Kao Zheng Pai 's Ashikawa Genan(朝川善庵) and medicine from Isawa Ranken and Taki Motokata(多紀元堅), and the secret to smallpox from Ikeda Keisui(池田京水). He later became a lecturer at the Edo Yi Xue Guan(醫學館) and was invited as the director to the Ji Zhong(濟衆) hospital. He also became the first owner of the Wen Zhi She(溫知社), whose main purpose was the revival of kampo, and launched the monthly magazine Wen Zi Yi Tan(溫知醫談). He also diagnosed and prescribed for the prince Ming Gong(明宮). His works include the "Jing Fang Bian"("經方辨"), "Shang Han Lun Si Ci"("傷寒論釋司"), "Huang Zhao Zhu Jia Zhi Yan Ji Yao"("皇朝諸家治驗集要") and "Shang Han Ja Bing Lun Lei Juan"("傷寒雜病論類纂"). of these, the "Jing Fang Bian"("經方辨") states that the Shi Gao(石膏) used in the "Shang Han Lun" had three meanings-Fa Biao(發表), Qing Re(淸熱), Zi Yin(滋陰)-which were from 'symptoms', and first deducted the effects and then told of the reason. Another book, the "Jiu Zhe Tang Du Shu Ji"("九折堂讀書記") researched and translated the difficult parts of the "Shang Han Lun", "Jin Qui Yao Lue", "Qian Jin Fang"("千金方"), and "Wai Tai Mi Yao"("外臺秘要"). He usually analyzed the 'symptoms' of diseases but the composition, measurement, processing and application of medicine were all in the spectrum of 'analystic research' and 'researching analysis'. 4) The ancestors of Mori Rits(森立之 1807${\sim}$ 1885) were warriors but he became a doctor by the will of his mother, and he learned from Shibue Chosai(澁江抽齋) and Isawaran Ken and later became a pupil of Shou Gu Yi Zhai, a historical research scholar. He then became a lecturer of medical herbs at the Yi Xue Guan, and later participated in the proofreading of "Yi Xin Fang"("醫心方") and with Chosai compiled the "Jing Ji Fang Gu Zhi"("神農本草經"). He visited the Chinese scholar Yang Shou Jing(楊守敬) in 1881 and exchanged books and ideas. Of his works, there are the collections(輯複本) of "Shen Nong Ben Cao Jing"(神農本草經) and "You Xiang Yi Hwa"("遊相醫話") and the records, notes, poems, and diaries such as "Zhi Yuan Man Lu"("枳園漫錄") and "Zhi Yuan Sui Bi"("枳園隨筆") that were not published. His thoughts were that in restoring the "Shen Nong Ben Cao Jing", "the herb to the doctor is like the "Shuo Wen Jie Zi"("說文解字") to the scholar", and he tried to restore the ancient herbal text using knowledge of medicine and investigation(考據). Also with Chosai he compiled the "Jing Ji Fang Gu Zhi"("經籍訪古志") using knowledge of ancient text. Ritzi left works on pure investigation, paid much attention to social problems, and through 12 years of poverty treated all people and animals in all branches of medicine, so he is called a 'half confucianist half doctor'(半儒半醫). 5) Kitamurana Ohira(喜多村直寬 1804${\sim}$1876) learned scriptures and ancient texts from confucian scholar Asaka Gonsai, and learned medicine from his father Huai Yaun(槐園). He became a teacher in the Yi Xue Guan in his middle ages, and to repay his country, he printed 266 volumes of "Yi Fang Lei Ju("醫方類聚") and 1000 volumes of "Tai Ping Yu Lan"("太平禦覽") and devoted it to his country to be spread. His works are about 40 volumes including "Jin Qui Yao Lue Shu Yi" and "Lao Yi Zhi Yan" but most of them are researches on the "Shang Han Za Bing Lun". In his "Shang Han Lun Shu Yi"("傷寒論疏義") he shows the concept of the six meridians through the Yin-Yang, Superficial or internal, cold or hot, deficient or replete state of diseases, but did not match the names with the six meridians of the meridian theory, and this has something in common with the research based on the confucianism of Song(宋儒). In clinical treatment he was positive toward old and new methods and also the experience of civilians, but was negative toward western medicine. 6) The ancestor of the Taki family Tanbano Yasuyori(丹波康賴 912-955) became a Yi Bo Shi(醫博士) by his medical skills and compiled the "Yi Xin Fang"("醫心方"). His first son Tanbano Shigeaki(丹波重明) inherited the Shi Yao Yuan(施藥院) and the third son Tanbano Masatada(丹波雅忠) inherited the Dian You Tou(典藥頭). Masatada's descendents succeeded him for 25 generations until the family name was changed to Jin Bao(金保) and five generations later it was changed again to Duo Ji(多紀). The research scholar Taki Motohiro was in the third generation after the last name was changed to Taki, and his family kept an important part in the line of medical officers in Japan. Taki Motohiro(多紀元簡 1755-1810) was a teacher in the Yi Xue Guan where his father was residing, and became the physician for the general Jia Qi(家齊). He had a short temper and was not good at getting on in the world, and went against the will of the king and was banished from Ao Yi Shi(奧醫師). His most famous works, the "Shang Han Lun Ji Yi" and "Jin Qui Yao Lue Ji Yi" are the work of 20 years of collecting the theories of many schools and discussing, and is one of the most famous books on the "Shang Han Lun" in Japan. "Yi Sheng" is a collection of essays on research. Also there are the "Su Wen Shi"("素問識"), "Ling Shu Shi"("靈樞識"), and the "Guan lu Fang Yao Bu"("觀聚方要補"). Taki Motohiro(多紀元簡)'s position was succeeded by his third son Yuan Yin(元胤 1789-1827), and his works include works of research such as "Nan Jing Shu Jeng"("難經疏證"), "Ti Ya"("體雅"), "Yao Ya"("藥雅"), "Ji Ya"("疾雅"), "Ming Yi Gong An"("名醫公案"), and "Yi Ji Kao"("醫籍考"). The "Yi Ji Kao" is 80 volumes in length and lists about 3000 books on medicine in China before the Qing Dao Guang(道光), and under each title are the origin, number of volumes, state of existence, and, if possible, the preface, Ba Yu(跋語) and biography of the author. The younger sibling of Yuan Yin(元胤 1789-1827), Yuan Jian(元堅 1795-1857) expounded ancient writings at the Yi Xue Guan only after he reached middle age, was chosen for the Ao Yi Shi(奧醫師) and later became a Fa Yan(法眼), Fa Yin(法印) and Yu Chi(樂匙). He left about 15 texts, including "Su Wen Shao Shi"("素間紹識"), "Yi Xin Fang"("醫心方"), published in school, "Za Bing Guang Yao"("雜病廣要"), "Shang Han Guang Yao"(傷寒廣要), and "Zhen Fu Yao Jue"("該腹要訣"). On the Taki family's founding and working of the Yi Xue Guan Yasuka Doumei(失數道明) said they were "the people who took the initiative in Edo era kampo medicine" and evaluated their deeds in the fields of 'research of ancient text', 'the founding of Ji Shou Guan and medical education', 'publication business', 'writing of medical text'. 5. The doctors of the 'Kao Zheng Pai ' based their operations on the Edo Yi Xue Guan, and made groups with people with similar ideas to them, making a relationship 'net'. For example the three families of Duo Ji(多紀), Tang Chuan(湯川) and Xi Duo Cun(喜多村) married and adopted with and from each other and made prefaces and epitaphs for each other. Thus, the Taki family, the state science of the Makufu, the tendency of thinking, one's own interests and glory, one's own knowledge, the need of the society all played a role in the development of kampo medicine in the 18th and 19th century.

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Ecological Changes of Insect-damaged Pinus densiflora Stands in the Southern Temperate Forest Zone of Korea (I) (솔잎혹파리 피해적송림(被害赤松林)의 생태학적(生態学的) 연구(研究) (I))

  • Yim, Kyong Bin;Lee, Kyong Jae;Kim, Yong Shik
    • Journal of Korean Society of Forest Science
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    • v.52 no.1
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    • pp.58-71
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    • 1981
  • Thecodiplosis japonesis is sweeping the Pinus densiflora forests from south-west to north-east direction, destroying almost all the aged large trees as well as even the young ones. The front line of infestation is moving slowly but ceaselessly norhwards as a long bottle front. Estimation is that more than 40 percent of the area of P. densiflora forest has been damaged already, however some individuals could escapes from the damage and contribute to restore the site to the previous vegetation composition. When the stands were attacked by this insect, the drastic openings of the upper story of tree canopy formed by exclusively P. densiflora are usually resulted and some environmental factors such as light, temperature, litter accumulation, soil moisture and offers were naturally modified. With these changes after insect invasion, as the time passes, phytosociologic changes of the vegetation are gradually proceeding. If we select the forest according to four categories concerning the history of the insect outbreak, namely, non-attacked (healthy forest), recently damaged (the outbreak occured about 1-2 years ago), severely damaged (occured 5-6 years ago), damage prolonged (occured 10 years ago) and restored (occured about 20 years ago), any directional changes of vegetation composition could be traced these in line with four progressive stages. To elucidate these changes, three survey districts; (1) "Gongju" where the damage was severe and it was outbroken in 1977, (2) "Buyeo" where damage prolonged and (3) "Gochang" as restored, were set, (See Tab. 1). All these were located in the south temperate forest zone which was delimited mainly due to the temporature factor and generally accepted without any opposition at present. In view of temperature, the amount and distribution of precipitation and various soil factor, the overall homogeneity of environmental conditions between survey districts might be accepted. However this did not mean that small changes of edaphic and topographic conditions and microclimates can induce any alteration of vegetation patterns. Again four survey plots were set in each district and inter plot distance was 3 to 4 km. And again four subplots were set within a survey plot. The size of a subplot was $10m{\times}10m$ for woody vegetation and $5m{\times}5m$ for ground cover vegetation which was less than 2 m high. The nested quadrat method was adopted. In sampling survey plots, the followings were taken into account: (1) Natural growth having more than 80 percent of crown density of upper canopy and more than 5 hectares of area. (2) Was not affected by both natural and artificial disturbances such as fire and thinning operation for the past three decades. (3) Lower than 500 m of altitude (4) Less than 20 degrees of slope, and (5) Northerly sited aspect. An intensive vegetation survey was undertaken during the summer of 1980. The vegetation was devided into 3 categories for sampling; the upper layer (dominated mainly by the pine trees), the middle layer composed by oak species and other broad-leaved trees as well as the pine, and the ground layer or the lower layer (shrubby form of woody plants). In this study our survey was concentrated on woody species only. For the vegetation analysis, calculated were values of intensity, frequency, covers, relative importance, species diversity, dominance and similarity and dissimilasity index when importance values were calculated, different relative weights as score were arbitrarily given to each layer, i.e., 3 points for the upper layer, 2 for the middle layer and 1 for the ground layer. Then the formula becomes as follows; $$R.I.V.=\frac{3(IV\;upper\;L.)+2(IV.\;middle\;L.)+1(IV.\;ground\;L.)}{6}$$ The values of Similarity Index were calculated on the basis of the Relative Importance Value of trees (sum of relative density, frequency and cover). The formula used is; $$S.I.=\frac{2C}{S_1+S_2}{\times}100=\frac{2C}{100+100}{\times}100=C(%)$$ Where: C = The sum of the lower of the two quantitative values for species shared by the two communities. $S_1$ = The sum of all values for the first community. $S_2$ = The sum of all values for the second community. In Tab. 3, the species composition of each plot by layer and by district is presented. Without exception, the species formed the upper layer of stands was Pinus densiflora. As seen from the table, the relative cover (%), density (number of tree per $500m^2$), the range of height and diameter at brest height and cone bearing tendency were given. For the middle layer, Quercus spp. (Q. aliena, serrata, mongolica, accutissina and variabilis) and Pinus densiflora were dominating ones. Genus Rhodedendron and Lespedeza were abundant in ground vegetation, but some oaks were involved also. (1) Gongju district The total of woody species appeared in this district was 26 and relative importance value of Pinus densiflora for the upper layer was 79.1%, but in the middle layer, the R.I.V. for Quercus acctissima, Pinus densiflora, and Quercus aliena, were 22.8%, 18.7% and 10.0%, respectively, and in ground vegetation Q. mongolica 17.0%, Q. serrata 16.8% Corylus heterophylla 11.8%, and Q. dentata 11.3% in order. (2) Buyeo district. The number of species enumerated in this district was 36 and the R.I.V. of Pinus densiflora for the uppper layer was 100%. In the middle layer, the R.I.V. of Q. variabilis and Q. serrata were 8.6% and 8.5% respectively. In the ground vegetative 24 species were counted which had no more than 5% of R.I.V. The mean R.I.V. of P.densiflora ( totaling three layers ) and averaging four plots was 57.7% in contrast to 46.9% for Gongju district. (3) Gochang-district The total number of woody species was 23 and the mean R.I.V. of Pinus densiflora was 66.0% showing greater value than those for two former districts. The next high value was 6.5% for Q. serrata. As the time passes since insect outbreak, the mean R.I.V. of P. densiflora increased as the following order, 46.9%, 57.7% and 66%. This implies that P. densiflora was getting back to its original dominat state again. The pooled importance of Genus Quercus was decreasing with the increase of that for Pinus densiflora. This trend was contradict to the facts which were surveyed at Kyonggi-do area (the central temperate forest zone) reported previously (Yim et al, 1980). Among Genus Quercus, Quercus acutissina, warm-loving species, was more abundant in the southern temperature zone to which the present research is concerned than the central temperate zone. But vice-versa was true with Q. mongolica, a cold-loving one. The species which are not common between the present survey and the previous report are Corpinus cordata, Beltala davurica, Wisturia floribunda, Weigela subsessilis, Gleditsia japonica var. koraiensis, Acer pseudosieboldianum, Euonymus japonica var. macrophylla, Ribes mandshuricum, Pyrus calleryana var. faruiei, Tilia amurensis and Pyrus pyrifolia. In Figure 4 and Table 5, Maximum species diversity (maximum H'), Species diversity (H') and Eveness (J') were presented. The Similarity indices between districts were shown in Tab. 5. Seeing Fig. 6, showing two-dimensional ordination of polts on the basis of X and Y coordinates, Ai plots aggregate at the left site, Bi plots at lower site, and Ci plots at upper-right site. The increasing and decreasing patterns as to Relative Density and Relative Importance Value by genus or species were given in Fig. 7. Some of the patterns presented here are not consistent with the previously reported ones (Yim, et al, 1980). The present authors would like to attribute this fact that two distinct types of the insect attack, one is the short war type occuring in the south temperate forest zone, which means that insect attack went for a few years only, the other one is a long-drawn was type observed at the temperate forest zone in which the insect damage went on continuously for several years. These different behaviours of infestation might have resulted the different ways of vegetational change. Analysing the similarity indices between districts, the very convincing results come out that the value of dissimilarity index between A and B was 30%, 27% between B and C and 35% between A and C (Table 6). The range of similarity index was obtained from the calculation of every possible combinations of plots between two districts. Longer time isolation between communities has brought the higher value of dissimilarity index. The main components of ground vegetation, 10 to 20 years after insect outbreak, become to be consisted of mainly Genus Lespedeza and Rhododendron. Genus Quercus which relate to the top dorminant state for a while after insect attack was giving its place to Pinus densiflora. It was implied that, provided that the soil fertility, soil moisture and soil depth were good enough, Genus Quercuss had never been so easily taken ever by the resistant speeies like Pinus densiflora which forms the edaphic climax at vast areas of forest land. Usually they refer Quercus to the representative component of the undisturbed natural forest in the central part of this country.

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