• Title/Summary/Keyword: 유사가능도

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Fly Ash Application Effects on CH4 and CO2 Emission in an Incubation Experiment with a Paddy Soil (항온 배양 논토양 조건에서 비산재 처리에 따른 CH4와 CO2 방출 특성)

  • Lim, Sang-Sun;Choi, Woo-Jung;Kim, Han-Yong;Jung, Jae-Woon;Yoon, Kwang-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.5
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    • pp.853-860
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    • 2012
  • To estimate potential use of fly ash in reducing $CH_4$ and $CO_2$ emission from soil, $CH_4$ and $CO_2$ fluxes from a paddy soil mixed with fly ash at different rate (w/w; 0, 5, and 10%) in the presence and absence of fertilizer N ($(NH_4)_2SO_4$) addition were investigated in a laboratory incubation for 60 days under changing water regime from wetting to drying via transition. The mean $CH_4$ flux during the entire incubation period ranged from 0.59 to $1.68mg\;CH_4\;m^{-2}day^{-1}$ with a lower rate in the soil treated with N fertilizer due to suppression of $CH_4$ production by $SO_4^{2-}$ that acts as an electron acceptor, leading to decreases in electron availability for methanogen. Fly ash application reduced $CH_4$ flux by 37.5 and 33.0% in soils without and with N addition, respectively, probably due to retardation of $CH_4$ diffusion through soil pores by addition of fine-textured fly ash. In addition, as fly ash has a potential for $CO_2$ removal via carbonation (formation of carbonate precipitates) that decreases $CO_2$ availability that is a substrate for $CO_2$ reduction reaction (one of $CH_4$ generation pathways) is likely to be another mechanisms of $CH_4$ flux reduction by fly ash. Meanwhile, the mean $CO_2$ flux during the entire incubation period was between 0.64 and $0.90g\;CO_2\;m^{-2}day^{-1}$, and that of N treated soil was lower than that without N addition. Because N addition is likely to increase soil respiration, it is not straightforward to explain the results. However, it may be possible that our experiment did not account for the substantial amount of $CO_2$ produced by heterotrophs that were activated by N addition in earlier period than the measurement was initiated. Fly ash application also lowered $CO_2$ flux by up to 20% in the soil mixed with fly ash at 10% through $CO_2$ removal by the carbonation. At the whole picture, fly ash application at 10% decreased global warming potential of emitted $CH_4$ and $CO_2$ by about 20%. Therefore, our results suggest that fly ash application can be a soil management practice to reduce green house gas emission from paddy soils. Further studies under field conditions with rice cultivation are necessary to verify our findings.

Bone Density and Related Factors of Food and Nutrition Major and Non-Major University Students in Seoul Area (서울지역 식품영양전공.비전공대학생의 골밀도에 미치는 영향요인에 관한 연구)

  • 정남용;최순남
    • Journal of the East Asian Society of Dietary Life
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    • v.13 no.5
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    • pp.391-407
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    • 2003
  • This study was conducted to investigate the factors affecting the born density of food and nutrition major and non-major university students in Seoul area. Data for food habits, dietary and health-related behavior were obtained by self administered questionnaires. BQI(bone quality index) of the subjects were measured by Quantitative Ultrasound (QUS). The results are summarized as follows: The average height, weight, BMI and osteopenia percentage of the major and non-major male and female student were l74.49cm, 67.05kg, 21.96 and 22.0%; l74.34cm, 65.98kg, 21.69 and 11.8%; l60.76cm, 54.48kg, 21.07 and 40.0%; l61.30cm, 54.22kg, 20.84 and 40.2%, respectively. The BQI of the major and non-major subjects were 108.07 and 110.47 in male student group, and 89.13, 88.18 in female student group, respectively. The T-score and Z-score of bone density of the subjects were not significantly different. Weight and BMI were positively related with BQI in male and female group but the relationship with BMI tended to be stronger in non-major female group than other groups. BQI was positively affected by exercise time, favorite food, and intake of seafood and tea in major and non-major male student group. One-side eating habit and intake of instant foods were negatively related with BQI in both male groups. In major and non-major female student group, exercise time, meal regularity, favorite food, amount of meal, intake of tofu were related with BQI positively and intake of tea and/or meats negatively. The result of this study revealed that desirable food habits, dietary behavior and health-related lifestyle may have a beneficial effect on bone density. They need practically and systematically organized nutrition education on optimum body weight, good eating habits, weight bearing exercise and intakes of good quality nutrient for higher bone density level.

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

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

A CLINICAL STUDY ON MANDIBULAR MOVEMENT AFTER ORTHOGNATHIC SURGERY (악교정 수술환자의 술전후 하악운동 양상변화에 관한 임상적 연구)

  • Baek, Sang-Heum;Jang, Hyun-Jung;Lee, Sang-Han;Kim, Hyun-Soo;Cha, Doo-Won
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.3
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    • pp.239-249
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    • 2001
  • The purpose of this study is to evaluate the relationship of the factors which could be influenced by orthognathic surgery especillay SSRO. We measured the amounts of the maximum opening, lateral movements, maximum velocity and pattern of mandibular path during the opening and closing of mandible at the following times ; preoperative, 1 month after operation, 6 months after operation respectively using MKG. And the results were compared according to the categorized subgroups. Following results were obtained : 1. The change of the amounts of mandibular lateral movement and maximum opening velocity were statistically different between male and female (p<0.05), but the others were not. 2. According to the method of operation, there was no difference in the change of the mandibular movements between the group of SSRO and SSRO plus LeFort I osteotomy (p>0.05). 3. According to the amounts of mandibular movement, the recovery of left lateral movement of the group of $6{\sim}10mm$ was better than the other groups (p<0.05). 4. In the frontal pattern of the opening and closing of the mandible, the complex deflected type (F5), simple deflected type (F4), complex deviated type (F3), simple deviated type (F2), straight type (F1) were obtained in order at the time of preoperative, simple deflected type, simple deviated type, complex deviated type, straight type, complex deflected type in order at the time of 1 month after surgery, and the result at the time of 6 months after surgery was the same with that of the time of preoperative. In the sagittal pattern, non-coincident type (S2) was predominant at the time of preoperative, and coincident type (S1) was predominant at the time of 1 month after surgery. After 6 months, the result was also the same with that of the preoperative in sagittal pattern. 5. There was not a statistical difference in the change of the mandibular movement between group of presence of the preoperative TMJ symptoms and non-presence group (p>0.05). 6. There was not a statistical difference in the change of the mandibular movement between repositioning device applied group and non-applied group (p>0.05). 7. Sixty three percents of the patients who had preoperative TMJ symptoms were improved after surgery and preoperative TMJ symptoms were more improved after operation in the repositioning device non-applied group statistically (p<0.05).

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A Study on Garden Design Principles in "Sakuteiki(作庭記)" - Focused on the "Fungsu Theory"(風水論) - (「사쿠테이키(作庭記)」의 작정원리 연구 - 풍수론(風水論)을 중심으로 -)

  • Kim, Seung-Yoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.6
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    • pp.1-19
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    • 2013
  • This study tries to review 'Sakuteiki(作庭記)', the Book of Garden Making, compiled at the end of the 11th Century during the Heian Period of Japan, from the East-Asian perspective. 'Sakuteiki' is a Garden Theory Book, the oldest in the world as well as in Asia, and it contains the traditional knowledge of Japanese ancient garden culture, which originated from the continent(Korea and China). Traditional knowledge related to East-Asian garden culture reviewed in this paper is "Fungsu Theory"(風水, Asian traditional ecology: Fengshui in Chinese; Fusui in Japanese), stemmed from the culture to seek sound and blessed places to live in. Viewed from modern landscape architecture, the Fungsu Theory corresponds to ecology(science). The Fungsu Theory was established around the Han Dynasty of China together with the Yinyangwuxing(陰陽五行) Theory and widely used for making human residences including gardens. It was transmitted to Japan via Korea as well as through direct transaction between Japan and China. This study reinterprets garden design principles represented in Sakuteiki, which were selected in 5 key words according to the Fungsu Theory. The 5 key words for the Fungsu Theory are "the place in harmony of four guardian gods(四神相應地)", "planting trees in the four cardinal directions", "flow of Chi(氣)", "curved line and asymmetry", and "mountain is the king, water is the people". Garden design principles of "the place in harmony of four guardian gods(四神相應地)" and "planting trees in the four cardinal directions" are corresponding to "Myeongdang-ron(明堂論, Theory of propitious site)". The place in harmony of four guardian gods mentioned in Sakuteiki is a landform surrounded by the flow of water to the east, the great path to the west, the pond to the south, and the hill to the north. And the Theory originated from Zhaijing(宅經, Classic of dwelling Sites) of China. According to this principle, the city was planned and as a miniature model, the residence of the aristocrat during the Heian period was made. At the residence the location of the garden surrounded by the four gods(the flow of water, the great path, the pond, and the hill) is the Myeongdang(明堂, the propitious site: Mingtang in Chinese; Meido in Japanese). Sakuteiki explains how to substitute for the four gods by planting trees in the four cardinal directions when they were not given by nature. This way of planting originated from Zhaijing(宅經) and also goes back to Qiminyaoshu (齊民要術), compiled in the 6th Century of China. In this way of planting, the number of trees suggested in Sakuteiki is related to Hetu(河圖) and Luoshu(洛書), which are iconography of Yi(易), the philosophy of change, in ancient China. Such way of planting corresponds to that of Yongdoseo(龍圖墅, the villa based on the principle of Hetu) presented in Sanrimgyeongje (山林經濟), an encyclopedia on agriculture and living in the 17th Century of Korea. And garden design principles of "the flow of Chi(氣)", "curved line and asymmetry" is connected to "Saenggi Theory(生氣論, Theory of vitality)". Sakuteiki explains the right flow of Chi(氣) through the proper flow and the reverse flow of the garden stream and also suggests the curved line of the garden stream, asymmetric arrangement of bridges and stones in the garden, and indented shape of pond edges, which are ways of accumulating Chi(氣) and therefore lead to "Saenggi Theory" of the Fungsu Theory. The last design principle, "mountain is the king, water is the people", is related to "Hyeongguk Theory(形局論, Theory of form)" of the Fungsu Theory. Sakuteiki explains the meaning of garden through a metaphor, which views mountain as king, water as the people, and stones as king's retainers. It compares the situation in which the king governs the people with the help of his retainers to the ecological phenomena in which mountain(earth) controls water with the help of stones. This principle befits "Hyeongguk Theory(形局論, Theory of form)" of the Fungsu Theory which explains landform on the analogy of social systems, people, animals and things. As above, major garden design principles represented in Sakuteiki can be interpreted in the context of the Fungsu Theory, the traditional knowledge system in East Asia. Therefore, we can find the significance of Sakuteiki in that the wisdom of ancient garden culture in East-Asia was integrated in it, although it described the knowhow of a specific garden style in a specific period of Japan.

Clinical Analysis of Acute Respiratory Tract Infections by Influenza Virus in Children (인플루엔자 바이러스에 의한 소아 급성 호흡기 감염증의 유행 및 임상 양상)

  • Kwon, Min Kyoung;Kim, Mi Ran;Park, Eun Young;Lee, Kon Hee;Yoon, Hae Sun;Kim, Kwang Nam;Lee, Kyu Man
    • Clinical and Experimental Pediatrics
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    • v.45 no.12
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    • pp.1519-1527
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    • 2002
  • Purpose : Although influenza virus is one of the most important causes of acute respiratory tract infections(ARTIs) in children, virus isolation is not popular and there are only a few clinical studies on influenza in Korea. We evaluated the epidemiologic and clinical features of ARTIs by influenza virus in children. Methods : From February 1995 to August 2001, nasopharyngeal aspirations were obtained and cultured for the isolation of influenza virus in children admitted with ARTIs. The medical records of patients with influenza virus infection were reviewed retrospectively. Results : Respiratory viruses were isolated in 997(22.0%) out of 4,533 patients examined, and influenza virus was isolated in 164 cases(3.6%). Influenza virus was isolated year after year mainly from December to April of next year. The ratio of male and female was 1.9 : 1 with a median age of 15 months. The most common clinical diagnosis of influenza virus infection was pneumonia, and fever and cough developed in most patients. There was no difference between influenza A and B infection in clinical diagnoses and symptoms. All patients recovered without receiving antiviral treatment except for one patient diagnosed with pneumonia who had underlying disease of Down syndrome with ventricular septal defect. Conclusion : ARTIs caused by influenza virus developed every winter and spring during the period of study. Because fatal complication can develop in the high risk group, prevention, early diagnosis and proper management of influenza should be emphasized.

The Results of Combined External Radiotherapy and Chemotherapy in the Management of Esophageal Cancer (식도암의 방사선-항암화학 병용치료결과)

  • Lee Hyun Joo;Suh Hyun Suk;Kim Jun Hee;Kim Chul Soo;Kim Sung Rok;Kim Re Hwe
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.17-23
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    • 1996
  • Purpose : To evaluate the role of combination therapy of external radio-therapy and chemotherapy in the management of advanced esophageal cancer as a primary treatment compared with radiation therapy alone. Materials and Methods : A retrospective review of evaluable 55 esophageal cancer patients referred to the Department of Therapeutic Radiology, Paik Hospital for the external radiotherapy between Jul, 1983 and Dec. 1994 was undertaken. Combined therapy patients (A group) were 30 and radiation alone patients (B group) were 25. Median age was 60 years old in A group (ranges : 42-81) and 65 years old in B group (ranges : 50-81). The male patients were 53. The fifty patients had squamous cell carcinomas. Radiation doses of 2520-6480c0y were delivered over a period of 4-7weeks, using 4MV LINAC. Chemotherapy was administered in bolus injection before, after, or during the course of external radiotherapy. The local control rate and patterns of failure according to both treatment modalities and 1, 2 year survival rates according to prognostic factors (stage, tumor length, radiation dose etc.) were analysed. Resuts : Median follow up Period was 7 months (range : 2-73 months). Median survival was 7.5 months (20 days-29 months) in A group and 5 months (20 days-73 months) in B group. The 1, 2 YSRs were $26.7\%$, $8.9\%$ in A group, $12.7\%$, $4.3\%$ in B group (p>0.05), respectively. The 1, 2 YSRs according to stage(II/III), tumor length (5cm more or less). radiation dose (5000cGymore or less) of A and B group were analyzed and the differences of survival rates of both treatments were not statistically significant. But among group B, patients who received 5000cGy or more showed significant survival benefits (p<0.05). The treatment response rates of A and B group were $43.8\%$. $25.0\%$, respectively. Complete response rate of $25.0\%$ in A and $8.3\%$ in B were achieved. The local failure and distant metastsis were $52.4\%$. $23.8\%$ in A group, $64.3\%$, $14.3\%$ in 8 group, respectively. The combination therapy revealed more frequent leukopenia and nausea/vomiting than radiation alone group, but degree of side effects was only mild to moderate. Conclusion : The combined external radiotherapy and chemotherapy for advanced esophageal cancer appears to improve the response rate, local control rate and survival rate, but the improvement was not statistically significant. The side effects of combined modalities were mild to moderate without significant morbidity. Therefore it may be worthwhile to continue the present combined external radiotherapy and chemotherapy in the management of advanced esophageal cancer to confirm our result.

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Results of Conventional Radiotherapy in Oropharyngeal Cancer (구인두암의 방사선 치료 성적)

  • Nam Taek Keun;Ahn Sung Ja;Chung Woong Ki;Nah Byung Sik
    • Radiation Oncology Journal
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    • v.14 no.1
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    • pp.1-8
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    • 1996
  • Purpose: We tried to evaluate the role of conventional radiotherapy alone or with neoadjuvant chemotherapy in oropharyngeal cancer in terms of survival rates and to identify prognostic factors affecting survival by retrospective analysis. Materials and Methods: Forty seven patients of oropharyngeal cancer were treated by conventional radiotherapy in our hospital from Nov. 1985 to APr. 1993. Of these, twenty six patients were treated by conventional radio-therapy alone, and 21 patients with neoadjuvant chemotherapy of mostly two or more cycles of cisplatin and pepleomycin. The Patient characteristics of radiotherapy alone group and neoadjuvant chemotherapy group were not different generally. Radiotherapy was performed by 6MV-LINAC and the total radiation doses of Primary tumors were 54.0-79.2 Gy and cervical lymph nodes were 55.8-90.0 Gy with a fraction size of 1.8 or 2.0 Gy per day. The range of follow-up periods was 3-102 months and median was 20 months. The range of a9e was 33-79 years old and median was 58 years old. Results : Overall 3-year actuarial survival rate (3YSR) of all patients was $39\%$. The 3YSRS of stage I (n=5), II (n=11), III (n=12) and IV (n=19) were 60, 55, 33 and $32\%$, respectively The 3YSRS of Tl+2, T3+4 and No, N+ were 55, $18\%$ (p=0.005) and 43, $36\%$ (p>0.1), respectively. There was no difference in 3YSRS between radiotherapy alone group and neoadjuvant chemotherapy group (38 vs $43\%$, p>0.1). According to the original site of primary tumor, the 3YSRS of tonsil (n=32), base of tongue (n=8), soft palate or uvula (n=6) and pharyngeal wall (n=1) were 36 38, 67 and $0\%$, respectively The Patients of soft palate or uvular cancer had longer survival than other primaries but the difference was not significant statistically (p>0.1). Of 32 patients of tonsillar cancer, 22 Patients who had primary extension to adjacent tissue showed inferior survival rate to the ones who had not Primary extension, but the difference was marginally significant statistically (24 vs $60\%$, p=0.08). On Cox multivariate analysis in entire patients with variables of age, T stage, N stage, total duration of radiotherapy, the site of primary tumor and the use of neoadjuvant chemotherapy, only T stage was a significant Prognostic factor affecting 3YSR. Conclusion : The difference of 3YASRS of conventional radiotherapy alone group and neoadjuvant chemotherapy group was not significant statistically. These treatments could be effective in oropharyngeal cancer of early stage, especially such as soft palate, uvular or tonsillar cancer which did not extend to adjacent tissue. But in order to improve the survival of patients of most advanced oropharyngeal cancer, other altered fractionated radiotherapy such as hyperfractionation rather than conventional fractionation or multi-modal approach combining radiotherapy and accessible surgery or concurrent chemotherapy might be beneficial.

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A Novel in Vitro Method for the Metabolism Studies of Radiotracers Using Mouse Liver S9 Fraction (생쥐 간 S9 분획을 이용한 방사성추적자 대사물질의 새로운 체외 측정방법)

  • Ryu, Eun-Kyoung;Choe, Yearn-Seong;Kim, Dong-Hyun;Lee, Sang-Yoon;Choi, Yong;Lee, Kyung-Han;Kim, Byung-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.4
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    • pp.325-329
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    • 2004
  • Purpose: Usefulness of mouse liver S9 fraction was evaluated for the measurement of the metabolites in the in vitro metabolism study of $^{18}F$-labeled radiotracers. Materials and Methods: Mouse liver S9 fraction was isolated at au early step in the course of microsome preparation. The in vitro metabolism studies were tarried out by incubating a mixture containing the radiotracer, S9 fraction and NADPH at $37^{\ciirc}C$, and an aliquot of the mixture was analyzed at the indicated time points by radio-TLC. Metabolic defluorination was further confirmed by the incubation with calcium phosphate, a bone mimic. Results: The radiotracer $[^{18}F]1$ underwent metabolic defluorination within 15 min, which was consistent with the results of the in vivo method and the in vitro method using microsome. Radiotracer $[^{18}F]2$ was metabolized to three metabolites including $4-[^{18}F]fluorobenzoic$ acid within 60 min. It is likely that the one of these metabolites at the origin of radio-TLC was identical with the one that obtained from the in vivo and in vitro (microsome) method. Compared with the in vitro method using microsome, the method using S9 fraction gave a similar pattern of the metabolites but with a different ratio, which can be explained by the presence of cytosol in the S9 fraction. Conclusion: These results suggest that the findings of the in vitro metabolism studies using S9 fraction can reflect the in vivo metabolism of novel radiotracers in the liver. Moreover, this method can be used as a tool to determine metabolic defluorination along with calcium phosphate absorption method.

Performance analysis of Frequent Itemset Mining Technique based on Transaction Weight Constraints (트랜잭션 가중치 기반의 빈발 아이템셋 마이닝 기법의 성능분석)

  • Yun, Unil;Pyun, Gwangbum
    • Journal of Internet Computing and Services
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    • v.16 no.1
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    • pp.67-74
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    • 2015
  • In recent years, frequent itemset mining for considering the importance of each item has been intensively studied as one of important issues in the data mining field. According to strategies utilizing the item importance, itemset mining approaches for discovering itemsets based on the item importance are classified as follows: weighted frequent itemset mining, frequent itemset mining using transactional weights, and utility itemset mining. In this paper, we perform empirical analysis with respect to frequent itemset mining algorithms based on transactional weights. The mining algorithms compute transactional weights by utilizing the weight for each item in large databases. In addition, these algorithms discover weighted frequent itemsets on the basis of the item frequency and weight of each transaction. Consequently, we can see the importance of a certain transaction through the database analysis because the weight for the transaction has higher value if it contains many items with high values. We not only analyze the advantages and disadvantages but also compare the performance of the most famous algorithms in the frequent itemset mining field based on the transactional weights. As a representative of the frequent itemset mining using transactional weights, WIS introduces the concept and strategies of transactional weights. In addition, there are various other state-of-the-art algorithms, WIT-FWIs, WIT-FWIs-MODIFY, and WIT-FWIs-DIFF, for extracting itemsets with the weight information. To efficiently conduct processes for mining weighted frequent itemsets, three algorithms use the special Lattice-like data structure, called WIT-tree. The algorithms do not need to an additional database scanning operation after the construction of WIT-tree is finished since each node of WIT-tree has item information such as item and transaction IDs. In particular, the traditional algorithms conduct a number of database scanning operations to mine weighted itemsets, whereas the algorithms based on WIT-tree solve the overhead problem that can occur in the mining processes by reading databases only one time. Additionally, the algorithms use the technique for generating each new itemset of length N+1 on the basis of two different itemsets of length N. To discover new weighted itemsets, WIT-FWIs performs the itemset combination processes by using the information of transactions that contain all the itemsets. WIT-FWIs-MODIFY has a unique feature decreasing operations for calculating the frequency of the new itemset. WIT-FWIs-DIFF utilizes a technique using the difference of two itemsets. To compare and analyze the performance of the algorithms in various environments, we use real datasets of two types (i.e., dense and sparse) in terms of the runtime and maximum memory usage. Moreover, a scalability test is conducted to evaluate the stability for each algorithm when the size of a database is changed. As a result, WIT-FWIs and WIT-FWIs-MODIFY show the best performance in the dense dataset, and in sparse dataset, WIT-FWI-DIFF has mining efficiency better than the other algorithms. Compared to the algorithms using WIT-tree, WIS based on the Apriori technique has the worst efficiency because it requires a large number of computations more than the others on average.