• Title/Summary/Keyword: 손실 원인

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Variation on Estimated Values of Radioactivity Concentration According to the Change of the Acquisition Time of SPECT/CT (SPECT/CT의 획득시간 증감에 따른 방사능농도 추정치의 변화)

  • Kim, Ji-Hyeon;Lee, Jooyoung;Son, Hyeon-Soo;Park, Hoon-Hee
    • The Korean Journal of Nuclear Medicine Technology
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    • v.25 no.2
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    • pp.15-24
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    • 2021
  • Purpose SPECT/CT was noted for its excellent correction method and qualitative functions based on fusion images in the early stages of dissemination, and interest in and utilization of quantitative functions has been increasing with the recent introduction of companion diagnostic therapy(Theranostics). Unlike PET/CT, various conditions like the type of collimator and detector rotation are a challenging factor for image acquisition and reconstruction methods at absolute quantification of SPECT/CT. Therefore, in this study, We want to find out the effect on the radioactivity concentration estimate by the increase or decrease of the total acquisition time according to the number of projections and the acquisition time per projection among SPECT/CT imaging conditions. Materials and Methods After filling the 9,293 ml cylindrical phantom with sterile water and diluting 99mTc 91.76 MBq, the standard image was taken with a total acquisition time of 600 sec (10 sec/frame × 120 frames, matrix size 128 × 128) and also volume sensitivity and the calibration factor was verified. Based on the standard image, the comparative images were obtained by increasing or decreasing the total acquisition time. namely 60 (-90%), 150 (-75%), 300 (-50%), 450 (-25%), 900 (+50%), and 1200 (+100%) sec. For each image detail, the acquisition time(sec/frame) per projection was set to 1.0, 2.5, 5.0, 7.5, 15.0 and 20.0 sec (fixed number of projections: 120 frame) and the number of projection images was set to 12, 30, 60, 90, 180 and 240 frames(fixed time per projection:10 sec). Based on the coefficients measured through the volume of interest in each acquired image, the percentage of variation about the contrast to noise ratio (CNR) was determined as a qualitative assessment, and the quantitative assessment was conducted through the percentage of variation of the radioactivity concentration estimate. At this time, the relationship between the radioactivity concentration estimate (cps/ml) and the actual radioactivity concentration (Bq/ml) was compared and analyzed using the recovery coefficient (RC_Recovery Coefficients) as an indicator. Results The results [CNR, radioactivity Concentration, RC] by the change in the number of projections for each increase or decrease rate (-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.5%, +3.90%, 1.04] at -90%, [-77.9%, +2.71%, 1.03] at -75%, [-55.6%, +1.85%, 1.02] at -50%, [-33.6%, +1.37%, 1.01] at -25%, [-33.7%, +0.71%, 1.01] at +50%, [+93.2%, +0.32%, 1.00] at +100%. and also The results [CNR, radioactivity Concentration, RC] by the acquisition time change for each increase or decrease rate (-90%, -75%, -50%, -25%, +50%, +100%) of total acquisition time are as follows. [-89.3%, -3.55%, 0.96] at - 90%, [-73.4%, -0.17%, 1.00] at -75%, [-49.6%, -0.34%, 1.00] at -50%, [-24.9%, 0.03%, 1.00] at -25%, [+49.3%, -0.04%, 1.00] at +50%, [+99.0%, +0.11%, 1.00] at +100%. Conclusion In SPECT/CT, the total coefficient obtained according to the increase or decrease of the total acquisition time and the resulting image quality (CNR) showed a pattern that changed proportionally. On the other hand, quantitative evaluations through absolute quantification showed a change of less than 5% (-3.55 to +3.90%) under all experimental conditions, maintaining quantitative accuracy (RC 0.96 to 1.04). Considering the reduction of the total acquisition time rather than the increasing of the image acquiring time, The reduction in total acquisition time is applicable to quantitative analysis without significant loss and is judged to be clinically effective. This study shows that when increasing or decreasing of total acquisition time, changes in acquisition time per projection have fewer fluctuations that occur in qualitative and quantitative condition changes than the change in the number of projections under the same scanning time conditions.

Studies on nutrient sources, fermentation and harmful organisms of the synthetic compost affecting yield of Agaricus bisporus (Lange) Sing (양송이 수량(收量)에 미치는 합성퇴비배지(合成堆肥培地)의 영양원(營養源), 발효(醱酵) 및 유해생물(有害生物)에 관((關)한 연구(硏究))

  • Shin, Gwan-Chull
    • The Korean Journal of Mycology
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    • v.7 no.1
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    • pp.13-73
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    • 1979
  • These studies were conducted to investigate nutrient sources and supplementary materials of synthetic compost media for Agaricus bisporus culture. Investigation were carried out to establish the optimum composition for compost of Agaricus bisporus methods of out-door fermentation and peakheating with rice straw as the main substrate of the media. The incidence and flora of harmful organisms in rice straw compost and their control were also studied. 1. When rice straw was used as the main substrate in synthetic compost as a carbon source. yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw, and the total nitrogen content was high in rice straw compost. 2. Since the morphological and physico-chemical nature of Japonica and Indica types of rice straw are greatly dissimilar. there were apparent differences in the process of compost fermentation. Fermentation of Indica type straw proceeded more rapidly with a shortening the compost period, reducing the water supply, and required adding of supplementary materials for producing stable physical conditions. 3. Use of barley straw compost resulted in a smaller crop compared with rice straw. but when a 50%, barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. 4. There were extremely high positive correlations between yield of Agaricus bisporus and the total nitrogen, organic nitrogen, amino acids, amides and amino sugar nitrogen content of compost. The mycerial growth and fruit body formation were severely inhibited by ammonium nitrogen. 5. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. 6. The supplementation of organic nutrient activated compost fermentation and increased yield of Agaricus bisporus. The best sources of organic nutrients were: perilla meal, sesame meal, wheat bran and poultry manure, etc. 7. Soybean meal, tobacco powder and glutamic acid fermentation by-products which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. B. When gypsum and zeolite were added to rice straw. physical deterioration of compost due to excess moisture and caramelization was observed. The Indica type of straw was more remarkable in increase of yield of Agricus bisporus by addition of supplementing materials than Japonica straw. 9. For preparing rice straw compost, the best mixture was prepared by 10% poultry manure, 5% perilla meal, 1. 2 to 1. 5% urea and 1% gypsum. At spring cropping, it was good to add rice bran to accelerate heat generation of the compost heap. 10. There was significantly high positive correlation (r=0.97) between accumulated temperature and the decomposition degree of compost during outdoor composting. The yield was highest at accumulated temperatures between 900 and $1,000^{\circ}C$. 11. Prolonging the composting period brought about an increase in decomposition degree and total nitrogen content, but a decrease in ammonium nitrogen. In the spring the suitable period of composting was 20 to 25 days. and about 15 days in autumn. For those periods, the degree of decomposition was 19 to 24%. 12. Compactness of wet compost at filling caused an increase in the residual ammonium nitrogen. methane and organic acid during peak heating. There was negative correlation between methane content and yield (r=0.76)and the same was true between volatile organic acid and yield (r=0.73). 13. In compost with a moisture content range between 69 to 80% at filling. the higher the moisture content, the lower the yield (r=0.78). This result was attributed to a reduction in the porosity of compost at filling the beds. The optimum porosity for good fermentation was between 41 and 53%. 14. Peak heating of the compost was essential for the prevention of harmful microorganisms and insect pests. and for the removal of excess ammonia. It was necessary to continue fer mentatiion for four days after peak heating. 15. Ten species of fungi which are harmful or competitive to Agaricus bisporus were identified from the rice compost, including Diehliomyces microsporus, Trichoderma sp. and Stysanus stemoites. The frequency of occurrance was notably high with serious damage to Agaricus bisporus. 16. Diehliomyces microsporus could be controlled by temperature adjustment of the growing room and by fumigating the compost and the house with Basamid and Vapam. Trichoderma was prevented by the use of Bavistin and Benomyl. 17. Four species of nematodes and five species of mites occured in compost during out-door composting. These orgnanisms could be controlled through peakheating compost for 6 hours at $60^{\circ}C$.

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Effect of Dietary Bacillus subtilis on Growth Performance, Immunological Cells Change, Fecal NH3-N Concentration and Carcass Meat Quality Characteristics in Finishing Pigs (비육돈 사료내 Bacillus subtilis의 첨가가 성장, 면역세포 변화, 분내 암모니아태질소 함량 및 도체 특성에 미치는 영향)

  • Cho, J.H.;Chen, Y.J.;Min, B.J.;Kim, H.J.;Shon, K.S.;Kwon, O.S.;Kim, J.D.;Kim, I.H.
    • Journal of Animal Science and Technology
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    • v.47 no.6
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    • pp.937-946
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    • 2005
  • This experiment was conducted to investigate the effects of dietary Bacillus subtilis on growth performance, nutrient digestibility, immunological cells change, fecal noxious gas and carcass meat quality characteristics in finishing pigs. The dietary treatments were 1) CON(basal diet), 2) BS0.1(basal diet+ 0.1% Bacillus subtilis) and 3)BS0.2(basal diet+0.2% Bacillus subtilis). Sixty crossbred(Landrace$\time$ Yorkshire$\time$Duroc) pigs(89.5$\pm$0.11kg average initial body weight) were used in a 42 days growth trial. The pigs were assigned to the treatments according to body weight and each treatment had 5 replicates of 4 pigs per pen in a randomized complete block design. Through the entire experimental period, average daily gain(ADG) and average daily feed intake(ADFI) were not significantly different among the treatments. Pigs fed BS0.1 diet significantly increased their gain/feed compared to pigs fed CON and BS0.2 diets(P<0.05). Also, dry matter(DM) and nitrogen(N) digestibilities were greater in the pigs fed BS0.1 diet than those fed CON diet(P<0.05). There were no significant differences in fecal NH3-N concentration among the treatments. In blood assay for immunological cells change investigations, red blood cells(RBC) counts increased in the pigs fed BS0.2 diet compared to pigs fed CON and BS0.1 diets. There were no significant differences in carcass pH, drip loss, marbling and firmness. However, sensual color and a*(redness) value of meat in the pigs fed BS0.2 diet were higher than in pigs fed CON diet(P<0.05). Therefore, this experiment suggested that Bacillus subtilis supplementation could improve nutrient digestibility, RBC counts and carcass meat color of pigs.

The study on outpatient-clinic practice by shift system at a hospital in Taegu (대구지역 한 중소병원의 교대제 근무에 의한 외래진료에 관한 연구)

  • Song, Jung Hup;Kim, Jing Kyun;Ha, Young Ae;Yeh, Min Hae
    • Quality Improvement in Health Care
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    • v.1 no.2
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    • pp.44-59
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    • 1994
  • Medical consumers(patients) want evening-clinic because of busy work. For patient's convenience and improving service, hospital should accept it. Considering payment system and patient's demand, personnel expenses, hospital can not accept. The practice of shift system to accept patient's demand and hospital's economic aspect was made. To analysis the effect of the system and probability to alternative to evening clinic this study was done. This study was composed of basal study, intervention, evaluation of effect. The basal study were composed of studying demand on evening clinic, the number of beds, doctors employee, the time table of practice and work, and the number of patients at arrival time. The intervention composed of changing of practice time, changing of working time by the number of patients at arrival time, increasing of employee. The evaluation of effect were composed of evaluating the number of patient at time, the effect of shift system, the comparison of the number of in and out patients and questionnairing the practice of shift system. In the practice time at 2 shift system First team works 7-15 hours and Second team 12-20 hours. there are no lunch and supper time. At 18-20 hours the number of patients were 25-30. The number of patient a depart were 6-7. The number of out-patient increase in 13% and inpatient increase in 10% before the system. Doctors(100%), employee(94.6%), and patients(86.4%) approved this system. The advantage of this system were utilization of surplus time, lengthen the practice time, even distribution of patients and shortening of waiting time, rapid treatment of emergent patients. The disadvantage of this system were shortage of manpower, not all depart practice, continuity of practice, no lunch and supper time, irregular rounding. At present because of small Demanding on evening clinic, this shift system was economical. To succeed this study more effectively all depart in hospital participate. But because of economical reason it is impossible for hospital to do it. If the government assist the economic loss that all depart participate in this system it is very helpful for hospital to succeed in implementing this system more early.

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Assessment of Carsington Dam Failure by Slope Stability and Dam Behavior Analyses (사면안정 해석과 댐 거동분석을 통한 Carsington Dam 파괴의 고찰)

  • 송정락;김성인
    • Proceedings of the Korean Geotechical Society Conference
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    • 1991.10a
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    • pp.87-102
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    • 1991
  • It has been reported that the failure of Carsington Dam in Eng1and occured due to the existence of a thin yellow clay layer which was not identified during the design work, and due to pre-existing shears of the clay layer. The slope stability analyses during the design work, which utilized traditional circular arc type failure method and neglected the existence of the clay layer, showed a safety factor of 1.4. However, the post-failure analyses which utilized translational failure mode considering the clay layer and the pre-existing shear deformation revealed the reduction of safety factor to unity. The post-failure analysis assumed 10。 inclination of the horizontal forces onto each slice based on the results of finite element analyses. In this paper, Bishop's simplified method, Janbu method, and Morgenstern-Price method were used for the comparison of both circular and translational failure analysis methods. The effects of the pre-existing shears and subsquent movement were also considered by varying the soil strength parameters and the pore pressure ratio according to the given soi1 parameters. The results showed factor of safefy 1.387 by Bishop's simplified method(STABL) which assumed circular arc failure surface and disregarding yellow clay layer and pre-failure material properties. Also the results showed factor of safety 1.093 by Janbu method(STABL) and 0.969 by Morgenstern-Price method(MALE) which assumed wedge failure surface and considerd yellow clay layer using post failure material properties. In addition, dam behavior was simulated by Cam-Clay model FEM program. The effects of pore pressure changes with loading and consolidation, and strength reduction near or at failure were also considered based on properly assumed stress-strain relationship and pore pressure characteristics. The results showed that the failure was initiated at the yellow clay layer and propagated through other zones by showing that stress and displacement were concentrated at the yel1ow clay layer.

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Evaluation of Water Quality Impacts of Forest Fragmentation at Doam-Dam Watershed using GIS-based Modeling System (GIS 기반의 모형을 이용한 도암댐 유역의 산림 파편화에 따른 수(水)환경 영향 평가)

  • Heo, Sung-Gu;Kim, Ki-Sung;Ahn, Jae-Hun;Yoon, Jong-Suk;Lim, Kyoungjae;Choi, Joongdae;Shin, Yong-Chul;Lyou, Chang-Won
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.4
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    • pp.81-94
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    • 2006
  • The water quality impacts of forest fragmentation at the Doam-dam watershed were evaluated in this study. For this ends, the watershed scale model, Soil and Water Assessment Tool (SWAT) model was utilized. To exclude the effects of different magnitude and patterns in weather, the same weather data of 1985 was used because of significant differences in precipitation in year 1985 and 2000. The water quality impacts of forest fragmentation were analyzed temporarily and spatially because of its nature. The flow rates for Winter and Spring has increased with forest fragmentations by $8,366m^3/month$ and $72,763m^3/month$ in the S1 subwatershed, experiencing the most forest fragmentation within the Doam-dam watershed. For Summer and Fall, the flow rate has increased by $149,901m^3/month$ and $107,109m^3/month$, respectively. It is believed that increased flow rates contributed significant amounts of soil erosion and diffused nonpoint source pollutants into the receiving water bodies. With the forest fragmentation in the S1 watershed, the average sediment concentration values for Winter and Spring increased by 5.448mg/L and 13.354mg/L, respectively. It is believed that the agricultural area, which were forest before the forest fragmentation, are responsible for increased soil erosion and sediment yield during the spring thaw and snow melts. For Spring and Fall, the sediment concentration values increased by 20.680mg/L and 24.680mg/L, respectively. Compared with Winter and Spring, the increased precipitation during Summer and Fall contributed more soil erosion and increased sediment concentration value in the stream. Based on the results obtained from the analysis performed in this study, the stream flow and sediment concentration values has increased with forest fragmentation within the S1 subwatershed. These increased flow and soil erosion could contribute the eutrophication in the receiving water bodies. This results show that natural functionalities of the forest, such as flood control, soil erosion protection, and water quality improvement, can be easily lost with on-going forest fragmentation within the watershed. Thus, the minimize the negative impacts of forest fragmentation, comprehensive land use planning at watershed scale needs to be developed and implemented based on the results obtained in this research.

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The Comparative Studies on the Terrestrial Insect Diversity in Protected Horticulture Complex and Paddy Wetland (시설원예단지와 논습지의 육상곤충 다양성 비교분석)

  • Son, Jin-Kwan;Kong, Min-Jae;Kang, Dong-Hyeon;Kang, Bang-hun;Yun, Sung-Wook;Lee, Si-Young
    • Journal of Wetlands Research
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    • v.18 no.4
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    • pp.386-393
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    • 2016
  • Agricultural ecosystem is recognized as a space for providing a variety of services, in addition to the food production that it originally encompassed, such as water purification, biological habitat, air purification, soil conservation, and landscape development. The construction of greenhouses in agricultural landscapes can cause deterioration of ecosystem services because of the increase of impermeable area and loss of biological habitats. This study aimed to compare insect diversity between different types of constructed greenhouses and paddy ecosystems. The target study area was selected by considering the distribution status of horticultural complexes and was classified as Single Vinyl Greenhouse, Multi Vinyl Greenhouse or Glass Greenhouse and they were compared with four paddies. The study locations were in Gu-Mi, Bu-Yeo, Ginje and Jin-Ju. A total of 2,333 individual insects belonging to 9 orders, 38 families, 76 genus, and 80 species were collected. The composition of orders was Hemiptera (22.37%), Coleoptera (18.42%), Hymenoptera (14.47%), Orthoptera (11.84%), and Diptera (10.53%). The average number of collected species were in the order Paddy (39.38 species) > Single Vinyl Greenhouse (35.50 species) > Multi Vinyl Greenhouse (22.50 species) > Glass Greenhouse (24.00 species). The Diversity Index (H') was Paddy (4.76) > Single Vinyl Greenhouse (4.57) > Multi Vinyl Greenhouse (4.12), and Glass Greenhouse (4.12). The Richness Index (RI) was Paddy (7.72) and Single Vinyl Greenhouse (7.03) > Multi Vinyl Greenhouse (4.99) and Glass Greenhouse (5.32). From our results, it can be seen that the biological diversity features of insects decreased when greenhouses are constructed.However, Single Vinyl Greenhouse is noted to promote insect diversity more than that by Multi Vinyl Greenhouse and Glass Greenhouse. Hence, when constructing greenhouses, it is necessary to consider insect habitat to conserve insect diversity.

Evaluation of Social Nicotine Dependence Using the Kano Test for Social Nicotine Dependence (KTSND-K) Questionnaire in Korea (Kano Test for Social Nicotine Dependence(KTSND-K) 설문지를 통한 한국인의 사회적 니코틴의존성의 평가)

  • Jeong, Jae Hee;Choi, Sang Bong;Jung, Wou Young;Byun, Min Gwang;Park, Moo Suk;Kim, Young Sam;Kim, Se Kyu;Chang, Joon;Yoshii, Chiharu;Kim, Sung Kyu
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.5
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    • pp.365-373
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    • 2007
  • Background: Smoking is one of the most important leading causes of morbidity and mortality. Smoking habit is recognized as nicotine dependence, which consists of physical and psychosocial dependence. To evaluate social nicotine dependence, the Kano Test for Social Nicotine Dependence (KTSND) working group developed a new questionnaire, which consists of 10 questions with a total score of 30 in Japan. We examined the social nicotine dependence among healthy adults using the new KTSND questionnaire and evaluated validity of the KTSND questionnaire in Korea. Method: We applied Korean KTSND questionnaire version 2 to employees of hospital, university students and people for medical examination and promotion test. Complete data obtained from the 741 responders were analyzed. Result: The mean age of responders was 31.8 years. Among them, males were 57.8%. Current smokers, ex-smokers, and non-smokers were 13.8%, 12.8%, and 73.4% respectively. According to smoking status, the total KTSND scores of current smokers were significantly higher than those of ex-smokers, and of non-smokers ($17.1{\pm}5.4$ versus $14.3{\pm}5.5$, and $12.3{\pm}5.5$, $p{\leq}0.001$). The total KTSND scores of males were higher than those of females, suggesting that males have a propensity for depending nicotine socially much more than females ($14.3{\pm}5.7$ and $11.7{\pm}5.4$ respectively, p<0.001). Eight of ten questions produced significantly different scores among three different smoking groups. When current smokers were sub-classified by heavy smoking index (HSI) that represented physical nicotine dependence, we did not find a significant difference of KTSND score between low HSI group (<4) and high HSI group (${\geq}4$), This finding suggested that the psychosocial dependence might play a different role from physical nicotine dependence in smoking. Most of the non-smokers (62.5%) had an experience of harmful passive smoking especially in public place. Conclusion: Our study suggested that the KTSND questionnaire could be a useful method to evaluate psychosocial aspects of smoking.

Mushroom Production Technology with Crop Residues (농산부산물(農産副産物)을 이용(利用)한 식용(食用)버섯 재배(栽培))

  • Cha, Dong-Yeul;Park, Jeong-Sik
    • Applied Biological Chemistry
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    • v.27
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    • pp.47-55
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    • 1984
  • The results of series studies on the ratio of supplements, out-door composting and out-door fermentation induced by using the rice straw as a main substrates at the cultivation of Agaricus bisporus, and the cultivation of Pleurotus ostreatus using the rice straw bundles on its compost are as follows; When rice straw for cultivation of A. bisporus was used as the main substrates in synthetic compost as a carbon source, yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw and the total nitrogen content was high in rice straw compost. Use of barley straw compost for cultivation of A. bisporus was shown of low yield compared with rice straw, but when a 50% barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. The total organic nitrogen on the compost were shown the positive relation to the yield of A. bisporus, but the ammonium nitrogen negative relation to the mycelial growth and yield of A. bisporus. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. The supplementation of organic nutrient activated compost fermentation and increased yield of A. bisporus. The best sources of organic nutrients selected were as follows: perilla meal, sesame meal, wheat bran and poultry manure, etc. Soybean meal, tobacco powder and glutamic acid fermentation byproducts which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. During out door composing of rice straw for cultivation of A. bisporus, using of tuner, composter and tunnel system increased up to 13% of its yield, and also cut down 34% of production Cost. The cultivation of P. ostreatus and utilizing of rice straw and wheat straw was established and its yield was high on the rice straw pots. When the substrates 'Rice straw' was heated by steam at $60^{\circ}C$ for 6 hr. mycelial growth of P. ostreatus was moderately rapid and its yield was high.

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Microbial Population Diversity of the Mud Flat in Suncheon Bay Based on 16S rDNA Sequences and Extracellular Enzyme Activities (남해안 갯벌 미생물의 세포외효소 활성 및 16S rDNA 분석에 의한 다양성 조사)

  • Kim, Yu-Jeong;Kim, Sung-Kyum;Kwon, Eun-Ju;Baik, Keun-Sik;Kim, Jung-Ho;Kim, Hoon
    • Applied Biological Chemistry
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    • v.50 no.4
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    • pp.268-275
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    • 2007
  • Diversity of the mud flat microbial population in Suncheon Bay was investigated by studying extracellular enzyme activities and 16S rDNA sequences. Four culturable bacterial strains with CMCase, xylanase and protease activities were isolated from the wetland and the mud flat. All the strains produced more xylanase activity than CMCase or protease activity, and the properties of the isolate enzymes from the wetland were similar to those from the mud flat. About 2,000 clones were obtained with the 16S rDNA amplified from the metagenomic DNA isolated from the mud samples. Based on the restriction pattern(s), seventeen clones were selected for base sequence analysis. Of the 17 clones, only 35% (6 clones) were found to be cultured strains and 65% (11 clones) to be uncultured strains. The similarities in the base sequences of the clones ranged from 91.0% to 99.9% with an average similarity of 97.3%. The clones could be divided into 7 groups, Proteobacteria (9 clones, 52.9%), Firmicutes (3 clones, 17.6%), Bacteroidetes (1 clone), Flavobacteria (1 clone), Verrucomicrobia (1 clone), Acidobacteria (1 clone), and Chloroflexi (1 clone). Most of the Proteobacteria clones were gamma Proteobacteria associated with oxidation-reduction of sulfur.