• Title/Summary/Keyword: Agriculture activities

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Screening of immune enhancement activities of the extracts from Rosa rugosae Radix (해당화 뿌리 추출물의 면역 증진 효과)

  • Lee, Mi-Kyoung;Lee, Seo-Ho;Choi, Geun-Pyo;Yu, Chang-Yeon;Lee, Sin-Yeong;Lee, Jin-Ha;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.11 no.1
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    • pp.13-18
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    • 2003
  • The biological activities of extracts from Rosa rugosae Radix were compared. About 78% of the growth of human hepato- carcinoma and 68% of human gastric cancer cell was inhibited in adding 0.5 mg/ml of the extracts of Rosa rugosae Radix respectively. The growth of human breast cancer cells was also inhibited in adding 0.5 mg/ml of the extracts as well as 66% of the human cancer cells. It was proved that the growth of human normal lung cell, scored as 20% for the extracts. Overall selectivity of the extracts on several human cancer cell line was over 4, which is higher than those from the Rosa rugosae Radix. The growth of both human immune B and T cells was enhanced up to 1.2 to 1.5 times by adding the extracts, compared to the controls. The secretion of tumor necrosis factor-alpha$(TNF-{\alpha})$ from T cell was also increased up to 61.9 pg/ml in adding the ethanol extract (0.5 mg/ml). Ethanol extract also increased up to about 61.3 pg/ml of interleukin-6(IL-6) from B cell.

Physiological Activity and Physicochemical Properties of Condensed Prunus mume Juice Prepared with Pectinase (Pectinase처리를 한 매실 농축액의 이화학적 특성 및 생리활성)

  • Kim, Jeong-Ho;Cho, Hyun-Dong;Won, Yeong-Seon;Park, Wool-Lim;Lee, Kwan-Woo;Kim, Hyuk-Joo;Seo, Kwon-Il
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1369-1378
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    • 2018
  • Prunus mume Siebold & Zucc., a member of the Rosaceae family (called Maesil in Korea), has been widely distributed in East Asia, e.g. Korea, Japan and China, and its fruit has been used as a traditional drug and health food. In this study, we evaluated physicochemical properties and physiological activities of condensed Prunus mume juice treated with pectinase (PJ). The values of total acidity, pH, sugar contents, turbidity moisture content of the PJ were 35.81%, 2.73, $54.36^{\circ}Brix$, 2.75 and 51.32%, respectively. The PJ had effective DPPH radical scavenging activity, reducing power effect, $H_2O_2$ scavenging activity and ${\beta}$-carotene bleaching effect. DPPH radical scavenging activities of PJ was 46.31%; their reducing power ($OD_{700}$) was 1.80; $H_2O_2$ scavenging activity of PJ was 91.62%; and ${\beta}$-carotene bleaching effect of PJ was 73.02%. Also, PJ showed effective levels of ${\alpha}$-glucosidase inhibition activity. The cell viability was measured by SRB assay. The PJ significantly decreased the cell viability of mouse melanoma cells (B16) and human melanoma cells (SK-MEL-2 and SK-MEL-28) in a dose-dependent manner, however, there was no effect on human keratinocyte HaCaT. In morphological study, PJ-treated SK-MEL-2 cells showed distorted and shrunken cell masses. Total polyphenol contents and total flavonoid contents of PJ were 588.31 mg% (gallic acid equivalent) and 860.45 mg% (rutin equivalent). The antiproliferative effect of PJ seems to be associated with the antioxidant activity of its flavonoid and polyphenol contents. In conclusion, PJ may be beneficial in development of a functional food material.

A Study on Commodity Asset Investment Model Based on Machine Learning Technique (기계학습을 활용한 상품자산 투자모델에 관한 연구)

  • Song, Jin Ho;Choi, Heung Sik;Kim, Sun Woong
    • Journal of Intelligence and Information Systems
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    • v.23 no.4
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    • pp.127-146
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    • 2017
  • Services using artificial intelligence have begun to emerge in daily life. Artificial intelligence is applied to products in consumer electronics and communications such as artificial intelligence refrigerators and speakers. In the financial sector, using Kensho's artificial intelligence technology, the process of the stock trading system in Goldman Sachs was improved. For example, two stock traders could handle the work of 600 stock traders and the analytical work for 15 people for 4weeks could be processed in 5 minutes. Especially, big data analysis through machine learning among artificial intelligence fields is actively applied throughout the financial industry. The stock market analysis and investment modeling through machine learning theory are also actively studied. The limits of linearity problem existing in financial time series studies are overcome by using machine learning theory such as artificial intelligence prediction model. The study of quantitative financial data based on the past stock market-related numerical data is widely performed using artificial intelligence to forecast future movements of stock price or indices. Various other studies have been conducted to predict the future direction of the market or the stock price of companies by learning based on a large amount of text data such as various news and comments related to the stock market. Investing on commodity asset, one of alternative assets, is usually used for enhancing the stability and safety of traditional stock and bond asset portfolio. There are relatively few researches on the investment model about commodity asset than mainstream assets like equity and bond. Recently machine learning techniques are widely applied on financial world, especially on stock and bond investment model and it makes better trading model on this field and makes the change on the whole financial area. In this study we made investment model using Support Vector Machine among the machine learning models. There are some researches on commodity asset focusing on the price prediction of the specific commodity but it is hard to find the researches about investment model of commodity as asset allocation using machine learning model. We propose a method of forecasting four major commodity indices, portfolio made of commodity futures, and individual commodity futures, using SVM model. The four major commodity indices are Goldman Sachs Commodity Index(GSCI), Dow Jones UBS Commodity Index(DJUI), Thomson Reuters/Core Commodity CRB Index(TRCI), and Rogers International Commodity Index(RI). We selected each two individual futures among three sectors as energy, agriculture, and metals that are actively traded on CME market and have enough liquidity. They are Crude Oil, Natural Gas, Corn, Wheat, Gold and Silver Futures. We made the equally weighted portfolio with six commodity futures for comparing with other commodity indices. We set the 19 macroeconomic indicators including stock market indices, exports & imports trade data, labor market data, and composite leading indicators as the input data of the model because commodity asset is very closely related with the macroeconomic activities. They are 14 US economic indicators, two Chinese economic indicators and two Korean economic indicators. Data period is from January 1990 to May 2017. We set the former 195 monthly data as training data and the latter 125 monthly data as test data. In this study, we verified that the performance of the equally weighted commodity futures portfolio rebalanced by the SVM model is better than that of other commodity indices. The prediction accuracy of the model for the commodity indices does not exceed 50% regardless of the SVM kernel function. On the other hand, the prediction accuracy of equally weighted commodity futures portfolio is 53%. The prediction accuracy of the individual commodity futures model is better than that of commodity indices model especially in agriculture and metal sectors. The individual commodity futures portfolio excluding the energy sector has outperformed the three sectors covered by individual commodity futures portfolio. In order to verify the validity of the model, it is judged that the analysis results should be similar despite variations in data period. So we also examined the odd numbered year data as training data and the even numbered year data as test data and we confirmed that the analysis results are similar. As a result, when we allocate commodity assets to traditional portfolio composed of stock, bond, and cash, we can get more effective investment performance not by investing commodity indices but by investing commodity futures. Especially we can get better performance by rebalanced commodity futures portfolio designed by SVM model.

Studies on the Microflora and Enzymes Influencing on Korea Native Kochuzang (Red Pepper Soybean Paste) Aging (재래식(在來式) 고추장 숙성(熟成)에 미치는 미생물(微生物) 및 그 효소(酵素)에 관(關)한 연구(硏究))

  • Lee, Ke-Ho;Lee, Myo-Sook;Park, Sung-O
    • Applied Biological Chemistry
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    • v.19 no.2
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    • pp.82-92
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    • 1976
  • The study was carried out to investigate the changes of the various chemical components and the microflora during the aging period of Korean navive Kochuzang. (Red pepper soybean paste) Korean native maeju loaves were separated into surface and inner parts. Three kinds of Korean native Kochuzang were prepared from surface part, inner part, and ordinary of maeju. The selection and the indentification of the high enzyme producing strains from the microflora and characteristics of their enzymes were studied. I. The changes of the various chemical components during the aging period of Kochuzang. 1) The changes of pH in the 3 kinds of Kochuzang displayed rapid decrease for the first 10 days after preparing and gradual curve of decrease until 60 days, but slight increase for the next 30 days. The pH of the surface part Kochuzang was lower than that of inner part or ordinary Kochuzang. 2) The total acid contents in the 3 kinds of Kochuzang showed gradual increase until the 60 days but it slowly reduced after this time. 3) The total nitrogen contents in the 3 kind of Kochuzang showed gradual inerease up to the 60 days, but slight decrease after this time. 4) The changes of trichloroacetic acid soluble nitrogen in the 3 kinds of Kochuzang showed a remarkable increase for the first 10 days, however gradual increase after this time. 5) The increase of amino nitrogen contents in the 3 kinds of Kochuzang seemed to be remarkable until the first 30 days, however to be less remarkable after this time. 6) The contents of reducing sugar in the 3 kinds of Kochuzang showed remarkable increase until the first 50 days and it slowly reduced after this time. II. The changes of microflora during the aging period of Kochuzang. 1) Aerobic, anaerobic bacteria and mold in the 3 kinds of Kochuzang were increased until the first 30 to 40 days, but they were reduced after this time. 2) No yeast in the three kinds of Kochuzang appeared until the first 20 days. Yeast were proved to grow, when the pH value was decreased below 5.4 after the 30 days. Yeasts in the surface part and ordinary Kochuzang were gradually increased and those in the inner part Kochuzang were decreased as aging. III. The selection and identification of high amylase and protease producing strains from the microflora during the aging period of Kochuzang. 1) The amylase and protease highly producing strains from microflora were identified as Bacillus subtilis-P, Bacillus subtilis-G, Bacillus licheniformis-K, Aspergillus oryzae-B. 2) Amylase activity of Aspergillus oryzae-B was highest among the strains and the strains in order of the higher activity to the lower one were Bacillus subtilis-P Bacillus licheniformis-K, Bacillus subtilis-G. Protease activities of Aspergillus oryzae-B and Bacillus subtilis-P were about the same and the strains in order of the higher activity to the lower one were Bacillus licheniformis-K, Bacillus subtilis-G. 3) Amylase activity was inhibited more than protease activity was with NaCl concentration. Amylase activity was inhibited by 45 to 65 percent and protease activity by 40 to 46 percent at the concentration of 15 percent NaCl, which was the average concentration of NaCl in Kochuzang.

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Analysis of Forestry Structure and Induced Output Based on Input - output Table - Influences of Forestry Production on Korean Economy - (산업관련표(産業關聯表)에 의(依)한 임업구조분석(林業構造分析)과 유발생산액(誘發生産額) -임업(林業)이 한국경제(韓國經濟)에 미치는 영향(影響)-)

  • Lee, Sung-Yoon
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.4
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    • pp.4-14
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    • 1974
  • The total forest land area in Korea accounts for some 67 percent of the nation's land total. Its productivity, however, is very low. Consequently, forest production accounts for only about 2 percent of the gross national product and a minor proportion of no more than about 5 percent versus primary industry. In this case, however, only the direct income from forestry is taken into account, making no reference to the forestry output induced by other industrial sectors. The value added Or the induced forestry output in manufacturing the primary wood products into higher quality products, makes a larger contribution to the economy than direct contribution. So, this author has tried to analyze the structure of forestry and compute the repercussion effect and the induced output of primary forest products when utilized by other industries for their raw materials, Hsing the input-output table and attached tables for 1963 and 1966 issued by the Bank of Korea. 1. Analysis of forestry structure A. Changes in total output Durng the nine-year period, 1961-1969, the real gross national product in Korea increased 2.1 times, while that of primary industries went up about 1. 4 times. Forestry which was valued at 9,380 million won in 1961, was picked up about 2. 1 times to 20, 120 million won in 1969. The rate of the forestry income in the GNP, accordingly, was no more than 1.5 percent both in 1961 and 1962, whereas its rate in primary industries increased 3.5 to 5.4 percent. Such increase in forestry income is attributable to increased forest production and rise in timber prices. The rate of forestry income, nonetheless, was on the decrease on a gradual basis. B. Changes in input coefficient The input coefficient which indicates the inputs of the forest products into other sectors were up in general in 1966 over 1963. It is noted that the input coefficient indicating the amount of forest products supplied to such industries closely related with forestry as lumber and plywood, and wood products and furniture, showed a downward trend for the period 1963-1966. On the other hand, the forest input into other sectors was generally on the increase. Meanwhile, the input coefficient representing the yolume of the forest products supplied to the forestry sector itself showed an upward tendency, which meant more and more decrease in input from other sectors. Generally speaking, in direct proportion to the higher input coefficient in any industrial sector, the reinput coefficient which denotes the use of its products by the same sector becomes higher and higher. C. Changes in ratio of intermediate input The intermediate input ratio showing the dependency on raw materials went up to 15.43 percent m 1966 from 11. 37 percent in 1963. The dependency of forestry on raw materials was no more than 15.43 percent, accounting for a high 83.57 percent of value added. If the intermediate input ratio increases in any given sector, the input coefficient which represents the fe-use of its products by the same sector becomes large. D. Changes in the ratio of intermediate demand The ratio of the intermediate demand represents the characteristics of the intermediary production in each industry, the intermediate demand ratio in forestry which accunted for 69.7 percent in 1963 went up to 75.2 percent in 1966. In other words, forestry is a remarkable industry in that there is characteristics of the intermediary production. E. Changes in import coefficient The import coefficient which denotes the relation between the production activities and imports, recorded at 4.4 percent in 1963, decreased to 2.4 percent in 1966. The ratio of import to total output is not so high. F. Changes in market composition of imported goods One of the major imported goods in the forestry sector is lumber. The import value increased by 60 percent to 667 million won in 1966 from 407 million won in 1963. The sales of imported forest products to two major outlets-lumber and plywood, and wood products and furniture-increased to 343 million won and 31 million won in 1966 from 240million won and 30 million won in 1963 respectively. On the other hand, imported goods valued at 66 million won were sold to the paper products sector in 1963; however, no supply to this sector was recorded in 1963. Besides these major markets, primary industries such as the fishery, coal and agriculture sectors purchase materials from forestry. 2. Analysis of repercussion effect on production The repercussion effect of final demand in any given sector upon the expansion of the production of other sectors was analyzed, using the inverse matrix coefficient tables attached to the the I.O. Table. A. Changes in intra-sector transaction value of inverse matrix coefficient. The intra-sector transaction value of an inverse matrix coefficient represents the extent of an induced increase in the production of self-support products of the same sector, when it is generated directly and indirectly by one unit of final demand in any given sector. The intra-sector transaction value of the forestry sector rose from 1.04 in 1963 to 1, 11 in 1966. It may well be said, therefore, that forestry induces much more self-supporting products in the production of one unit of final demand for forest products. B. Changes in column total of inverse matrix coefficient It should be noted that the column total indicates the degree of effect of the output of the corresponding and related sectors generated by one unit of final demand in each sector. No changes in the column total of the forestry sector were recorded between the 1963 and 1966 figures, both being the same 1. 19. C. Changes in difference between column total and intra-sector transaction amount. The difference between the column total and intra-sector transaction amount by sector reveals the extent of effect of output of related industrial sector induced indirectly by one unit of final demand in corresponding sector. This change in forestry dropped remarkable to 0.08 in 1966 from 0.15 in 1963. Accordingly, the effect of inducement of indirect output of other forestry-related sectors has decreased; this is a really natural phenomenon, as compared with an increasing input coefficient generated by the re-use of forest products by the forestry sector. 3. Induced output of forestry A. Forest products, wood in particular, are supplied to other industries as their raw materials, increasng their value added. In this connection the primary dependency rate on forestry for 1963 and 1966 was compared, i. e., an increase or decrease in each sector, from 7.71 percent in 1963 to 11.91 percent in 1966 in agriculture, 10.32 to 6.11 in fishery, 16.24 to 19.90 in mining, 0.76 to 0.70 in the manufacturing sector and 2.79 to 4.77 percent in the construction sector. Generally speaking, on the average the dependency on forestry during the period 1963-1966 increased from 5.92 percent to 8.03 percent. Accordingly, it may easily be known that the primary forestry output induced by primary and secondary industries increased from 16, 109 million won in 1963 to 48, 842 million won in 1966. B. The forest products are supplied to other industries as their raw materials. The products are processed further into higher quality products. thus indirectly increasing the value of the forest products. The ratio of the increased value added or the secondary dependency on forestry for 1963 and 1966 showed an increase or decrease, from 5.98 percent to 7.87 percent in agriculture, 9.06 to 5.74 in fishery, 13.56 to 15.81 in mining, 0.68 to 0.61 in the manufacturing sector and 2.71 to 4.54 in the construction sector. The average ratio in this connection increased from 4.69 percent to 5.60 percent. In the meantime, the secondary forestry output induced by primary and secondary industries rose from 12,779 million Wall in 1963 to 34,084 million won in 1966. C. The dependency of tertiary industries on forestry showed very minor ratios of 0.46 percent and 0.04 percent in 1963 and 1966 respectively. The forestry output induced by tertiary industry also decreased from 685 million won to 123 million won during the same period. D. Generally speaking, the ratio of dependency on forestry increased from 17.68 percent in 1963 to 24.28 percent in 1966 in primary industries, from 4.69 percent to 5.70 percent in secondary industries, while, as mentioned above, the ratio in the case of tertiary industry decreased from 0.46 to 0.04 percent during the period 1963-66. The mining industry reveals the heaviest rate of dependency on forestry with 29.80 percent in 1963 and 35.71 percent in 1966. As it result, the direct forestry income, valued at 8,172 million won in 1963, shot up to 22,724 million won in 1966. Its composition ratio lo the national income rose from 1.9 percent in 1963 to 2.3 per cent in 1966. If the induced outcome is taken into account, the total forestry production which was estimated at 37,744 million won in 1963 picked up to 105,773 million won in 1966, about 4.5 times its direct income. It is further noted that the ratio of the gross forestry product to the gross national product. rose significantly from 8.8 percent in 1963 to 10.7 percent in 1966. E. In computing the above mentioned ratio not taken into consideration were such intangible, indirect effects as the drought and flood prevention, check of soil run-off, watershed and land conservation, improvement of the people's recreational and emotional living, and maintenance and increase in the national health and sanitation. F. In conclusion, I would like to emphasize that the forestry sector exercices an important effect upon the national economy and that the effect of induced forestry output is greater than its direct income.

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Study on the Long-term Forecasting of Brown Planthopper Outbreaks (벼멸구 발생의 장기예찰을 위한 기초적 연구)

  • Paik Woon Hah;Paik Hyun Joon
    • Korean journal of applied entomology
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    • v.16 no.3 s.32
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    • pp.171-179
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    • 1977
  • Since the outbreak of the brown planthopper (Nilaparvata lugens) in 1915 caused tremendous losses in rice production, one of the more effective method of prevention of such a disaster could be the establishment of longterm forecasting system, In 1916 the author indicated there was a correlation between sunspot activities and brown planthopper and the white back planthopper outbreaks. However, the examples seem to be too small size to state a definite correlation. The purpose of the present study IS to revi~w the history of the brown planthopper outbreaks, and to establish a more effective forcasting system. The present forcasting methods are based on light trap catches of adults which already migrate into this country from mainland China. The regular cycle of 11.2 years of sunspot activity began in 1710, and was continued to present. To gather more records of brown planthopper, the author checked 'Joseon Wangjo Silrok' and analized the so-called 'Hwang' 'Hwang-chung' and 'Chung' which have multiple meanings, together with 'Samguk Sagi' 'Goryo Sa' and 'Munheon Bigo.' The results obtained by the about from review of these old literature citations revealed that ten species of insect and unknown species were involved: i. e., pine moth (Dendrolimus spectabilis), army worm (Mythimna separata), brown planthopper (Nilarvata lugens), white-back planthopper (Sogatella furcifera), migratory locust (Locutsa migratoria), rice stem borer (Chilo suppressalis,), mole cricket (Gryllotalpa africana), rice-plant weevil (Echinocnemus squameus), cut worm (Euxoa segetum), and mulberry pyralid Margaronia pyloalis) The suspected incidence of planthopper in old records expressed by 'Hwang' or 'Chung' revealed a total or 25 out of 37 in 'Samguk sagi,' 21 out of 49 in 'Goryo sa,' 9 of 73 in 'Wanjo-silrog,' and none of 8 in 'Munheon bigo' were planthoppers. Therefore, a total of 36 out of 167 records of insect incidence in the old literature can be possibly attributed to planthoppers. The brown planthopper and white-back planthopper migrate together to Korea every year from mainland China, However, the number of each species are differ by year. In 1975 outbreak the brown planthopper was dominant; and the white-back planthopper prevailed in 1946 and 1977 outbreaks, During the course of this study, the author was able to add a new record of outbreak of planthop per. In 1916 the white-back planthopper outbreak caused serious losses in Chungcheong-namdo and Jeonla-namdo, with losses estimated as high as 160 and 190 thousand seok (23.2 and 27.5 thousand M/T), in Naju and Secheon county, respectively. Since 1912, major outbreaks of brown planthopper or white-back planthopper have been recored 5 times. These occurrences coincide and well matched the period of minimum number of sunspots, With these authenticated records of planthoppers, the author believes there is a close correlation between brown planthopper and white-back planthopper outbreaks in Korea and sunspot activities. Therefore, in years of low number of sunspots, we should watch for and expect outbreaks of these. insects. At this time, it will be necessary to provide all possible prevention measures.

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Physiological and Ecological Characteristics of Indigenous Soybean Rhizobia Distributed in Korea -II. Studies on Some Physiological Characteristics and Nitrogen Fixation Activity Under Free-Living Conditions of Indigenous Rhizobia (우리나라 토착대두근류균(土着大豆根瘤菌)의 분포상태(分布狀態)와 생리(生理) 및 생태학적(生態學的) 특성(特性) -제(第)II보(報) : 토착근류균(土着根瘤菌)의 질소고정력(窒素固定力)과 생리적특성(生理的特性)에 관(關)한 연구(硏究))

  • Ryu, Jin-Chang;Lee, Seong-Jae;Suh, Jang-Sun;Cho, Moo-Je
    • Korean Journal of Soil Science and Fertilizer
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    • v.19 no.2
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    • pp.157-165
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    • 1986
  • This experiment was conducted to find out the some physiological characteristics and nitrogen fixation activities under free-living conditions of indigenous rhizobia isolated from soybean-cultivated (30 fields) and un-cultivated (30 fields) soil. The results were summerized as follows: 1. In free-living condition, only 12.8% and 6.4% of the indigenous rhizobia isolated from soybean cultivated (133 strains) and un-cultivated (125 strains) soils were nitrogenase positive as more than 4 n mole $C_2H_4$ per tube per hour by acetylene reduction assay. 2. The acid-producing rhizobia on litmus milk test was observed to be 20% of the total 160 strains isolated from soybean cultivated soil but about 34% of 166 strains isolated from un-cultivated soil. And the serum zone positive strains were higher in the soybean un-cultivated soil than cultivated soil. 3. The population ratio of fast-to slow-growing indigenous rhizobia based on growth pattern of AMA medium was 35.6% to 64.4% of the total 346 strains. 4. The population of indigenous Rhizobium japonicum counted by MPN method was ranged from $9.2{\times}10^2$ cells per gram of soil in soybean un-cultivated soil to $2.3{\times}10^4$ cells per gram of soil soybean cultivated soil. The number of indigenous R. japonicum in 0-10cm depth of surface layer was higher than low layer.

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A Study on the Current Rotation System of Hunting Ground (현행(現行) 순환수렵장(循環狩獵場) 제도(制度)에 관(關)한 연구(硏究))

  • Byun, Woo Hyuk
    • Journal of Korean Society of Forest Science
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    • v.74 no.1
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    • pp.47-55
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    • 1986
  • During the past 4 years, I have made a careful analysis of the present rotating system of hunting areas, on the one hand, by asking a group of hunters to fill out a questionnaire, and on the other hand, by referring to the written documents on the subject. And, as a result, it is concluded that this system, by varying the hunting grounds each year, contains in itself several problems as follows. 1. The hunters find it quite inconvenient to use a different hunting ground year after year and they also complain that the present hunting ground charge is more than it is worth. Therefore, it is expected that the number of hunters will explosively increase in the future with the betterment of hunting conditions. 2. The hunters have almost no information about game and they are, as a whole, lacking in the ethics of hunting. 3. The allotment of time in hunting training courses is not so sufficient that it is next to impossible to improve the quality of hunters. 4. As a rule, the population density of wildlife is so sparse that it falls short of the proper standard of it. 5. The present hunting system does not seem to contribute to the advancement of tourism. 6. It is absolutely necessary to make a general survey of the situation of wildlife for the legal protection of it. Besides, the interests of hunters are so closely tied up with those of farmers and foresters that dreastic measures should be taken to settle their conflicting differences. For the purpose of solving the above-mentioned problems and at the same time, of developing sound hunting practices in the long run, I hereby make two suggestions. 1. The Establishment of the Hunting License Test System It is desirable to issue a license to a prospective hunter after he has met a special qualification and then passed a test so that he may have bits of information needed for his hunting activities. 2. The Introduction of The Revier System The fundamental concept of this system is based on the assumption that the private landowner should reserve a right to the pursuit of game and take responsibility for wildlife management.

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Effect of Plant Growth Regulators in Minimizing Low Temperature Stress in Rice(Oryza sativa L.) (식물생장조절제(植物生長調節劑) 처리(處理)가 벼(Oryza sativa L.) 냉해경감(冷害輕減)에 미치는 영향(影響))

  • Yoon, Jong Yeon;Lee, Sang Chul;Choi, Jang Su
    • Current Research on Agriculture and Life Sciences
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    • v.11
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    • pp.43-54
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    • 1993
  • This experiment was conducted at Andong county cropping season to investigate rice response and consequent changes in the physiological activities and agronomic characters of rice as affected by growth regulator treatments, and to determine how low temperature controls some plant growth mechanisms. Plant growth regulators, particularly ABA, applied to 15 DAT regardless of concentration, gave higher tar plant height and tiller number after 10days of low temperature treatment than did the untreated plant. However, the differences in plant height and tiller number among treatments diminished to plant growth. Chlorophyll content seemed to be enhanced by growth regulators under low temperature condition. The 10-day treatment of low temperature decreased chlorophyll content by more than 17% compared with the untreated control. The oxidizing activity of roots decreased sharply to 52.2a after 10 days in low temperature condition. On the other hand, ABA at concentration of $10^{-4}M$, highly attains oxiding activity of roots. Generally, plant growth regulators applied at 15 DAT under low temperature reduced grain yield more than did the untreated control which can be attributed to decreased yield components. When growth regulators were applied to booting stage, the tiller number did not show significant difference, whereas the significant difference in culm length at harvest was observed in all treatment as a result of different concentration of growth regulators. The growth regulators generally exhibited a significant effect on yield component except on panicle length. Grain yield of low temperature treated plot at booting stage was significantly influenced by application of growth regulators. This was due to decreased number of spikelet and low filled spikelet percentage. However, TIBA treatment at booting stage showed no significant differences in grain yield.

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Enzymatic Studies on the α-Galactosidases from Soybean and Aspergillus niger (대두(大豆) 및 Aspergillus niger α-galactosidase의 효소학적(酵素學的) 연구(硏究))

  • Keum, Jong-Hwa;Oh, Man-Jin
    • Korean Journal of Agricultural Science
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    • v.18 no.1
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    • pp.49-73
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    • 1991
  • To elucidate enzymatic properties of $\alpha$-galactosidases (EC3, 2, 1, 22) from germinated soybean and Aspergillus niger changes in the enzyme activities and oligosaccharide contents during germination of soybean were determined and $\alpha$-galactosidases from germinated soybean and wheat bran culture of Aspergillus niger were purified by ammonium sulfate fractionation, ion exchange chromatography and gel filtration. Their chemical and enzymatic properties were investigated and the results obtained were summarized as follows : 1. $\alpha$-Galactosidase activity of soybean was maximized when it was germinated at $25^{\circ}C$ for 120 hours. And raffinose and stachyose in soybean were decomposed completely after 96 hours and 120 hours of germination, respectively. 2. The highest level of $\alpha$-Galactosidase activity was obtained when Aspergillus niger was grown on wheat bran medium at $30^{\circ}C$ for 96 hours. 3. Soybean $\alpha$-galactosidase was purified by 6.6 fold by ammonium slufate fractionation, ion exchange chromatography on DEAE-Cellulose and Sephadex A-50., and gel filtration on Sephadex G-150. Its specific activity was 825 units/mg protein and the yield was 2.5% of the total activity of crude extracts. 4. Aspergillus niger $\alpha$-galactosidase was purified by 23.7 fold. Its specific activity was 1,229 units/mg protein and the yield was 14% of the total activity of wheat bran culture. 5. The purified $\alpha$-galactosidases of soybean and Aspergillus niger were found to be homogeneous by polyacrylamide gel electrophoresis and by HPLC. 6. Chemical properties of the purified $\alpha$-galactosidases were : 1) The soybean $\alpha$-galactosidase was monomeric and its molecular weight was estimated to be 30,000 by SDS-PAGE whereas the Aspergillus niger $\alpha$-galactosidase was a tetrameric glycoprotein which consisted of identical subunits with molecular weight of 28,000 each.

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