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A Study on a Quantitative Method in Estimating Forest Effects for Streamflow Regulation (II) - Mainly Dealing with Application of Coefficient for Slope Roughness - (삼림이수기능(森林理水機能)의 정량적(定量的) 평가방법(平價方法)에 관한 연구(硏究)(II) - 조도계수(粗度係數)의 응용(應用)을 중심(中心)으로 -)

  • Lee, Heon Ho
    • Journal of Korean Society of Forest Science
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    • v.81 no.4
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    • pp.337-345
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    • 1992
  • In this research, a kinematic wave model was applied for the runoff analysis, Regulation of streamflow was estimated by the calibration of roughness coefficient as a parameter. The data analyzed were obtained from Ananomiya and Shirasaka experimental basins at Tokyo University Forest in Aichi. Estimation methods and characteristics of roughness coefficient as a evaluation method of hydrological function of forest are summarized as follows ; 1. Roughness coefficient($N_s$) indicates the resistance of hillslope to the flowing water of surface runoff. There exists an hypothesis that resistance of hillslope to flowing water increase with the growth forest and development of the $A_o$ layer. 2. Roughness coefficient($N_s$) was estimated by the parameter when the stream direct runoff was calculated by using the kinematic wave. 3. Secular change of '$N_s$' in ananomiya has a curve which has an upper limit and increases exponentially near the limit. The curve quickly increased from 1935 to 1945 when results of afforestation for erosion control were thought to be effective. On the other hand, slight increase of '$N_s$' in Shirasaka indicates that there was not such a big change in the surface of soil layer. 4. The increase of '$N_s$' was related with decrease of direct runoff and increase of base flow. It was recognized that the rate of direct runoff decreased with the improvement of forest physiognomy and the rate of base flow was increased. But absolute value of water runoff per one storm decreased in chronological order.

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Effects of Cirsium japonicum Powder on Plasma Glucose and Lipid Level in Streptozotocin Induced Diabetic Rats (엉겅퀴 섭취가 Streptozotocin 유발 당뇨 흰쥐의 혈당과 지질수준에 미치는 영향)

  • Han, Hye-Kyoung;Je, Hee-Sun;Kim, Gun-Hee
    • Korean Journal of Food Science and Technology
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    • v.42 no.3
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    • pp.343-349
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    • 2010
  • This investigation was conducted to assess the influence of Cirsium japonicum consumption on the plasma glucose and lipid profiles in streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced in male Sprague-Dawley rats weighing 230 g by injection of STZ into the tail vein at 45 mg/kg body weight. The rats were randomly assigned into four groups: a normal and STZ-control fed an AIN-93 diet group, and diabetic groups whose diets were supplemented with 10% Cirsium japonicum powder containing leaf or root for four weeks. To observe the effects of Cirsium japonicum in the animal model, the levels of glucose, cholesterol, HDL-cholesterol, triglyceride and free fatty acid in the plasma and the levels of glycogen in the tissue were determined after four weeks. Treatment of STZ-induced diabetic rats with leaf consumption significantly lowered the diet intake when compared with STZ-control rats. The relative weights of the liver and kidney differed significantly between the normal and diabetic groups. The weights of the kidneys in the leaf group were significantly lower than those in the STZ-control group. The level of hematocrit was also significantly lower in diabetic rats whose diets were supplemented with leaves when compared to those of STZ-control rats. The plasma glucose level was found to be significantly lower in the leaf group than the STZ-control group. The effect was significant after 2 weeks. The HDL-cholesterol levels increased in all of the diabetic experimental groups when compared to the STZ-control group. These results suggest that supplementation with Circicum japonicum leaves induced considerable hypoglycemic effect in STZ-induced diabetic rats and that these leaves may be useful for the management of diabetes mellitus.

Antioxidant Activities and Hepato-protective Effects of Stauntonia hexaphylla Fruit Extract Against H2O2-induced Oxidative Stress and Acetaminophen-induced Toxicity (멀꿀 열매 추출물의 항산화 활성 및 H2O2로 유도된 산화적 스트레스와 아세트아미노펜 독성 모델에서의 간 보호효과)

  • Lee, Gyuok;Kim, Jaeyong;Kang, Huwan;Bae, Donghyuck;Choi, Chul-yung
    • Journal of Life Science
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    • v.28 no.6
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    • pp.708-717
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    • 2018
  • The antioxidant activity and protective effects of a hot water extract from the Stauntonia hexaphylla fruit (WESHF) were investigated in vitro and in vivo. The total polyphenol and flavonoid contents of WESHF were $16.13{\pm}0.27mg$ gallic acid equivalent/g and $4.7{\pm}0.80mg$ catechin equivalent/g, respectively. In addition, the DPPH radical-scavenging activity ($SC_{50}$) and the Oxygen Radical Absorbance capacity of WESHF were $63.62{\pm}4.10{\mu}g/ml$ and $90.63{\pm}5.29{\mu}M$ trolox equivalent/g, respectively. The hepatoprotective effect of WESHF against hydrogen peroxide-induced oxidative damage was investigated. $H_2O_2$-induced liver damage on HepG2 cells was prevented by $200{\mu}g/ml$ of WESHF. Furthermore, to investigate the protection mechanism of WESHF on hydrogen peroxide-induced cytotoxicity in HepG2 cells, pre-treatment with $200{\mu}g/ml$ of WESHF significantly attenuated a decrease in the activities of CAT, SOD, GR, and GPx. The hepatoprotective activity of WESHF was evaluated in an experimental model of hepatic damage induced by acetaminophen (APAP). The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly decreased in the livers of mice treated with 200 mg/kg of WESHF compared to the APAP-treated group. The lipid peroxidation level, which increased after APAP administration, was significantly reduced in the WESHF group. In addition, histological examinations of the liver showed the same protective effect of WESHF treatment. Based on these findings, it is suggested that WESHF has potent hepatoprotective effects, and the mechanism that causes this type of protection could be related to antioxidant pathways.

평행식 진동탄환 암거 천공기의 연구 (IV)(V)-실기 설계 제작 및 보장실험-Development of Balanced-Type Oscillating Mole Drainer(IV)(V)

  • 김용환;이승규;서상용
    • Journal of Biosystems Engineering
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    • v.2 no.1
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    • pp.7-24
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    • 1977
  • This paper is the forth and fifth one of the study on balanced type oscillating mole drainer. In the light of the results from previous reports about the model tests, some design criteria were established and a prototype machine was set up for experimental purpose. Motion characteristics and functionof the each parts of the machine were checked and analyzed. After that, performance tests of the prototype machine were carried out in thefield. Obtained results are summarized as follows ; 1. Ten centimeter of the bullet diameter was determined so as to be able to attach it to the tractors with capacity of 30 PS to 40 PS. 2. To maintain the balance between the moments of the front shank and rear shank, the oscillating amplitude of the rear bullet was determined to be larger than that of the front bullet. At the same time , the oscillating direction of the rear bullet was designed with the inclines of ten to thirty degrees. 3. An octagonal dynamo transduced was developed for measuring the compressive force of the upper link is measuring the draft force of the machine. Acceptable linear relationship between forces and strain responses from O.D.T. was obtained. 4. Analysing the balancing mechanism of the acting part of the machine , it was found that the total draft force of the machine was equal to the difference between the sum of the draft force produced from the right and left side bending moments of the lower drawber and the compressive force on the upper link. 5. There are acceptable linear relationship between the strain and twisting moment by driving shaft, and between strain and shank moment. Above results enable us to carry out the field experiment with prototype machine. 6. When the test machine was used in the field, it was possible to reduce the oscillating acceleration by forty percent in average as compared it with the single bullet mole drainer. 7. When the test machine was used under the oscillating condition, the dratt torce was reduced by 27 percent to 59 percent as compared it with the test machine under non-oscillating condition, while the draft force was increased by 7 percent to 20 percent as compared it with the mole drainer having oscillating single bullet. The reasoning behind this fact was considered as the resistance force due to the rear shank and bullet. 8. As the amplitude and frequency of the bullet were increased, the torque was increased accordingly. This tendency could be varied with the various characteristics of the given soils. And the larger frequency and amplitute, the more increasing oscil\ulcornerlating power but decreasing draft brce were needed, and draft force was increased as the velocity was increased.9. When the amplitude of the rear bullet was designed to be larger than that of the front bullet, the minimum value of the moment was lowered and oscillating acceleration was reduced. And when the oscillating direction of the rear bullet was declined back\ulcornerwards, oscillating acceleration was increased along with the increasing angle of decli\ulcornernation. When the test machine was operated in high speed, the difference between maximum moments and minimum ones became narrow. This varying magnitude of moments appeared on the moment oscillogram seems to be correlated to the oscillating acceleration and draft force. 10. From the analysis of variance, it was found that those factors such as frequency, amplitude, and operating velocity significantly affected in the oscillating acceleration, the draft resistance, the torque, the moment, and the total power required. And interaction between frequency and amplitude affected in the oscillating acceleration. 11. Within the given situation of this study, the most preferable operating conditions of the test machine were 7 Hz in oscillating frequency, 0.54 m/sec in operating velocity, and 39.1 mm in oscillating amplitude of front and rear bullets. However, it is necessary to select the proper frequency and magnitude of oscillation depending on the soil properties of the field in which the mole drainer is practiced by use of a bal1nced type oscillating mole drainer. 12. It is recommended that a comparative study of the mole drainers would be performed in the near future using two separate balanced oscillating bullet with the one which is operated by oscillating the movable bullet in a single cylinder or other balanced type which may be single oscillating bullet with spring, damper or balancing weight, and that of thing. To expand the applicability of the balanced type oscillating mole drainer in practical use, it is suggested to develop a new mechanism which perform mole drain with vinyl pipe or filling material such as rice hull.

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Current status of Brassica A genome analysis (Brassica A genome의 최근 연구 동향)

  • Choi, Su-Ryun;Kwon, Soo-Jin
    • Journal of Plant Biotechnology
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    • v.39 no.1
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    • pp.33-48
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    • 2012
  • As a scientific curiosity to understand the structure and the function of crops and experimental efforts to apply it to plant breeding, genetic maps have been constructed in various crops. Especially, in the case of Brassica crop, genetic mapping has been accelerated since genetic information of model plant $Arabidopsis$ was available. As a result, the whole $B.$ $rapa$ genome (A genome) sequencing has recently been done. The genome sequences offer opportunities to develop molecular markers for genetic analysis in $Brassica$ crops. RFLP markers are widely used as the basis for genetic map construction, but detection system is inefficiency. The technical efficiency and analysis speed of the PCR-based markers become more preferable for many form of $Brassica$ genome study. The massive sequence informative markers such as SSR, SNP and InDels are also available to increase the density of markers for high-resolution genetic analysis. The high density maps are invaluable resources for QTLs analysis, marker assisted selection (MAS), map-based cloning and comparative analysis within $Brassica$ as well as related crop species. Additionally, the advents of new technology, next-generation technique, have served as a momentum for molecular breeding. Here we summarize genetic and genomic resources and suggest their applications for the molecular breeding in $Brassica$ crop.

Human Lung Cancer Cell Xenografts Implanted under the Capsule of Kidney, Spleen and Liver (폐암 세포주를 사용한 신, 비장 및 간 피막하 분식법의 비교)

  • 김수현;김종인;이해영;조봉균;박성달;김송명
    • Journal of Chest Surgery
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    • v.36 no.10
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    • pp.711-720
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    • 2003
  • Bakground : Complete resection by the surgery has been selected as the treatment of choice in lung cancer patients, but in cases of recurrence after excision or inoperable cases, the importance of anticancer chemotherapy has been emphasized. If one can select a set of the sensitive chemotherapeutic agents before anticancer chemotherapy, it will give more favourable results. Subrenal capsular assay has been recognized as a useful in-vivo chemosensitivity test of thoracic and abdominal tumors and it can be done in a short time for a rapid interpretation of tumor responsiveness to anticancer chemotherapeutic drugs. It has been reported that various kinds of cancer cells can be implantable to the kidney, but so far there is no comparative study of xenogeneic cell implantation on liver, spleen and kidney. The author implanted the human lung cancer cells under the capsule of S.D rat's liver, spleen and kidney respectively and compared the pattern of growth and histology. Material and Method: After incubation of human lung cancer cell line (SW-900 G IV) in RPMI 1640 (Leibovitz L-15 medium) culture media, 3${\times}$3${\times}$3 mm size fibrin clots which contain 108 cancer cells were made. Thereafter the fibrin clots were implanted at subcapsule area of liver, spleen and kidney of S.D. female rat. For immune suppression, cyclosporin-A (80 mg/Kg) was injected subcutaneously daily from post-implantation first day to sixth day. The body weight was measured at pre and post implantation periods. The growth pattern and the size of tumor mass were observed and the pathologic examination and serum tumor marker tests were performed. Result: Body weight increased in both of control and experimental groups. Serum Cyfra 21-1 was not detected. Serum levels of CEA and NSE revealed no significant change. The SCC-Ag increased significantly in implanted group. The growth rate of human lung cancer cells which was implanted on spleen was higher than on liver or kidney. The surface area, thickness, and volume of tumor mass were predominant at spleen. The success rates of implantation were 80% on kidney, 76.7% on spleen and 43.3% on liver. Pathologic examination of implanted tumors showed characteristic findings according to different organs. Tumors that were implanted on kidney grew in a round shape, small and regular pattern. In the spleen, tumors grew well and microscopic neovascularization and tumor thrombi were also found, but the growth pattern was irregular representing frequent daughter mass. Human lung cancer cells that were implanted in the liver, invaded to the liver parenchyme, and had low success rate of implantation. Microscopically, coagulation necrosis and myxoid fibrous lesion were observed. Conclusion: The success rate of implantation was highest in the kidney. And the mass revealed regular growth that could be measured easily. The SCC-Ag was presented earlier than CEA or Cyfra21-1. The Cyfra21-1 was not detected at early time after implantation. The best model for tumor implantation experiment for chemosensitivity test was subrenal capsular analysis than liver and spleen and the useful serum tumor marker in early period of implantation was the SCC-Ag.

Risk Factors Related to Uterine Leiomyoma in Korean Women - A Retrospective Study - (한국인 여성에서 자궁근종 발생에 관여하는 인자들에 대한 연구 - 후향적 연구 -)

  • Hong, D.G.;Chung, M.J.;Kim, B.S.;Lee, J.M.;Cho, Y.L.;Lee, T.H.;Chun, S.S.
    • Clinical and Experimental Reproductive Medicine
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    • v.33 no.3
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    • pp.159-170
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    • 2006
  • Objective: The purpose of this study is to find out risk factors related to uterine leiomyoma in Korean women and to compare with the results of previous western studies. Methods: A retrospective analysis was carried out. All the cases of uterine leiomyoma (n=244) were diagnosed surgically or sonographically between Jannuary 1998 and December 2004. Total of 269 controls not having uterine leiomyoma were collected from patients who visited Kyungpook national university hospital for routine gynecologic check-up or treatment of their gynecologic or obstetric diseases other than uterine leiomyoma. Data were collected through review of medical records and interviews and analyzed with $x^2$ and logistic regression model. Results: In multivariate analysis, patient's age (OR 1.070; 95% CI 1.041~1.099), number of artificial abortion (OR 1.182; 95% CI 1.018~1.374) and alcohol drinking (OR 1.865; 95% CI 1.231~2.824) had significantly positive correlation with uterine leiomyoma. The duration of lactation was the only factor which had negative correlation (OR 0.985; 95% CI 0.972~0.998). BMI, parity, age at menarche, the duration and interval of menstruation, caffeine consumption and marital status did not show any correlations. Conclusion: In this study, patient's age, number of artificial abortion, and alcohol drinking were the risk factors of uterine leiomyoma in Korean women and the result was similar to that of western studies. Though we couldn't find out the specific risk factors related to the development of uterine leiomyoma in this study, but it has a great meaning to be the first trial in Korean women. The role of information bias should be carefully evaluated and further multicentered, randomized, controlled prospective studies will be needed to know the possible risk factors among Korean women.

A Graph Layout Algorithm for Scale-free Network (척도 없는 네트워크를 위한 그래프 레이아웃 알고리즘)

  • Cho, Yong-Man;Kang, Tae-Won
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.5_6
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    • pp.202-213
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    • 2007
  • A network is an important model widely used in natural and social science as well as engineering. To analyze these networks easily it is necessary that we should layout the features of networks visually. These Graph-Layout researches have been performed recently according to the development of the computer technology. Among them, the Scale-free Network that stands out in these days is widely used in analyzing and understanding the complicated situations in various fields. The Scale-free Network is featured in two points. The first, the number of link(Degree) shows the Power-function distribution. The second, the network has the hub that has multiple links. Consequently, it is important for us to represent the hub visually in Scale-free Network but the existing Graph-layout algorithms only represent clusters for the present. Therefor in this thesis we suggest Graph-layout algorithm that effectively presents the Scale-free network. The Hubity(hub+ity) repulsive force between hubs in suggested algorithm in this thesis is in inverse proportion to the distance, and if the degree of hubs increases in a times the Hubity repulsive force between hubs is ${\alpha}^{\gamma}$ times (${\gamma}$??is a connection line index). Also, if the algorithm has the counter that controls the force in proportion to the total node number and the total link number, The Hubity repulsive force is independent of the scale of a network. The proposed algorithm is compared with Graph-layout algorithm through an experiment. The experimental process is as follows: First of all, make out the hub that exists in the network or not. Check out the connection line index to recognize the existence of hub, and then if the value of connection line index is between 2 and 3, then conclude the Scale-free network that has a hub. And then use the suggested algorithm. In result, We validated that the proposed Graph-layout algorithm showed the Scale-free network more effectively than the existing cluster-centered algorithms[Noack, etc.].

Effects of growth hormone treatment on glucose metabolism in idiopathic short stature (특발성 저신장증 환자에서 성장 호르몬 투여가 당 대사에 미치는 영향)

  • Kwon, Seung Yeon;Kim, Duk-Hee;Kim, Ho-Seong
    • Clinical and Experimental Pediatrics
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    • v.49 no.6
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    • pp.665-671
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    • 2006
  • Purpose : To study the effects of growth hormone(GH) treatment on glucose metabolism and insulin resistance in children with idiopathic short stature(ISS). Methods : Glucose and insulin concentrations were measured during oral glucose tolerance test (OGTT) before and after GH treatment(0.6-0.7 IU/kg/week) in 20 patients with ISS. Insulin resistance was assessed by homeostasis model assessment(HOMA). Results : During OGTT, the mean blood glucose level did not show any significant changes after GH treatment. However, mean blood insulin levels of fasting and 30 minutes of OGTT showed significant increases after GH treatment, accompanying significant increases of insulin resistance. There was no difference in change of glucose, insulin levels and insulin resistance before and after GH treatment between two groups of body mass indices(BMI) of 25< and >25. There also was no significant difference between two groups of with and without family histories of diabetes mellitus (DM). There was no case of newly developed impaired glucose tolerance, fasting glucose tolerance, nor newly developed DM. Conclusion : GH treatment with doses of 0.6-0.7 IU/kg/week for mean 9.6 months in patients with ISS did not show any significant changes in blood glucose levels during OGTT. However, GH treatments induced considerably higher fasting insulin levels compared to pretreatment, resulting in statistically higher insulin resistance. Higher BMI and family history of DM did not induce any significant changes in glucose, insulin level and insulin resistance after GH treatment than the other groups.

Taurine exerts neuroprotective effects via anti-apoptosis in hypoxic-ischemic brain injury in neonatal rats (신생 흰쥐의 저산소성 허혈성 뇌손상에서 항세포사멸사를 통한 taurine의 신경보호 효과)

  • Jeong, Ji Eun;Kim, Tae Yeol;Park, Hye Jin;Lee, Kye Hyang;Lee, Kyung Hoon;Choi, Eun Jin;Kim, Jin Kyung;Chung, Hai Lee;Seo, Eok Su;Kim, Woo Taek
    • Clinical and Experimental Pediatrics
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    • v.52 no.12
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    • pp.1337-1347
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    • 2009
  • Purpose:Taurine (2-aminoethanesulfonic acid) is a simple sulfur-containing amino acid. It is abundantly present in tissues such as brain, retina, heart, and skeletal muscles. Current studies have demonstrated the neuroprotective effects of taurine, but limited data are available for such effects during neonatal period. The aim of this study was to determine whether taurine could reduce hypoxic-ischemic (HI) cerebral injury via anti-apoptosis mechanism. Methods:Embryonic cortical neurons isolated from Sprague-Dawley (SD) rats at 18 days gestation were cultured in vitro. The cells were divided into hypoxia group, taurine-treated group before hypoxic insult, and taurine-treated group after HI insult. In the in vivo model, left carotid artery ligation was performed in 7-day-old SD rat pups. The pups were exposed to hypoxia, administered an injection of 30 mg/kg of taurine, and killed at 1 day, 3 days, 1 week, 2 weeks, and 4 weeks after the hypoxic insult. We compared the expressions of Bcl-2, Bax, and caspase-3 among the 3 groups by using real- time polymerase chain reaction (PCR) and western blotting. Results:The cells in the taurine-treated group before hypoxic insult, although similar in appearance to those in the normoxia group, were lesser in number. In the taurine-treated group, Bcl-2 expression increased, whereas Bax and caspase-3 expressions reduced. Conclusion:Taurine exerts neuroprotective effects onperinatal HI brain injury due to its anti-apoptotic effect. The neuroprotective effect was maximal at 1-2 weeks after the hypoxic injury.