• Title/Summary/Keyword: C2 Model

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A prediction model for adolescents' skipping breakfast using the CART algorithm for decision trees: 7th (2016-2018) Korea National Health and Nutrition Examination Survey (의사결정나무 CART 알고리즘을 이용한 청소년 아침결식 예측 모형: 제7기 (2016-2018년) 국민건강영양조사 자료분석)

  • Sun A Choi;Sung Suk Chung;Jeong Ok Rho
    • Journal of Nutrition and Health
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    • v.56 no.3
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    • pp.300-314
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    • 2023
  • Purpose: This study sought to predict the reasons for skipping breakfast by adolescents aged 13-18 years using the 7th Korea National Health and Nutrition Examination Survey (KNHANES). Methods: The participants included 1,024 adolescents. The data were analyzed using a complex-sample t-test, the Rao Scott χ2-test, and the classification and regression tree (CART) algorithm for decision tree analysis with SPSS v. 27.0. The participants were divided into two groups, one regularly eating breakfast and the other skipping it. Results: A total of 579 and 445 study participants were found to be breakfast consumers and breakfast skippers respectively. Breakfast consumers were significantly younger than those who skipped breakfast. In addition, breakfast consumers had a significantly higher frequency of eating dinner, had been taught about nutrition, and had a lower frequency of eating out. The breakfast skippers did so to lose weight. Children who skipped breakfast consumed less energy, carbohydrates, proteins, fats, fiber, cholesterol, vitamin C, vitamin A, calcium, vitamin B1, vitamin B2, phosphorus, sodium, iron, potassium, and niacin than those who consumed breakfast. The best predictor of skipping breakfast was identifying adolescents who sought to control their weight by not eating meals. Other participants who had low and middle-low household incomes, ate dinner 3-4 times a week, were more than 14.5 years old, and ate out once a day showed a higher frequency of skipping breakfast. Conclusion: Based on these results, nutrition education targeted at losing weight correctly and emphasizing the importance of breakfast, especially for adolescents, is required. Moreover, nutrition educators should consider designing and implementing specific action plans to encourage adolescents to improve their breakfast-eating practices by also eating dinner regularly and reducing eating out.

Evaluation of Endothelium-dependent Myocardial Perfusion Reserve in Healthy Smokers; Cold Pressor Test using $H_2^{15}O\;PET$ (흡연자에서 관상동맥 내피세포 의존성 심근 혈류 예비능: $H_2^{15}O\;PET$ 찬물자극 검사에 의한 평가)

  • Hwang, Kyung-Hoon;Lee, Dong-Soo;Lee, Byeong-Il;Lee, Jae-Sung;Lee, Ho-Young;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.1
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    • pp.21-29
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    • 2004
  • Purpose: Much evidence suggests long-term cigarette smoking alters coronary vascular endothelial response. On this study, we applied nonnegative matrix factorization (NMF), an unsupervised learning algorithm, to CO-less $H_2^{15}O-PET$ to investigate coronary endothelial dysfunction caused by smoking noninvasively. Materials and methods: This study enrolled eighteen young male volunteers consisting of 9 smokers $(23.8{\pm}1.1\;yr;\;6.5{\pm}2.5$ pack-years) and 9 nonsmokers $(23.8{\pm}2.9 yr)$. They do not have any cardiovascular risk factor or disease history. Myocardial $H_2^{15}O-PET$ was performed at rest, during cold ($5^{\circ}C$) pressor stimulation and during adenosine infusion. Left ventricular blood pool and myocardium were segmented on dynamic PET data by NMF method. Myocardial blood flow (MBF) was calculated from input and tissue functions by a single compartmental model with correction of partial volume and spillover effects. Results: There were no significant difference in resting MBF between the two groups (Smokers: 1.43 0.41 ml/g/min and non-smokers: $1.37{\pm}0.41$ ml/g/min p=NS). during cold pressor stimulation, MBF in smokers was significantly lower than 4hat in non-smokers ($1.25{\pm}0.34$ ml/g/min vs $1.59{\pm}0.29$ ml/gmin; p=0.019). The difference in the ratio of cold pressor MBF to resting MBF between the two groups was also significant (p=0.024; $90{\pm}24%$ in smokers and $122{\pm}28%$ in non-smokers.). During adenosine infusion, however, hyperemic MBF did not differ significantly between smokers and non-smokers ($5.81{\pm}1.99$ ml/g/min vs $5.11{\pm}1.31$ ml/g/min ; p=NS). Conclusion: in smokers, MBF during cold pressor stimulation was significantly lower compared wi4h nonsmokers, reflecting smoking-Induced endothelial dysfunction. However, there was no significant difference in MBF during adenosine-induced hyperemia between the two groups.

Antitumor and Antimetastatic Effects of Toxoplasma Gondii in Mice with Lewis Lung Carcinoma (Lewis 폐암 마우스 모델에서 톡소포자충에 의한 항암 및 항전이 효과)

  • Kim, Ju-Ock;Jung, Sung-Soo;Park, Hee-Sun;Kim, Myoung-Hoon;Kim, Sun-Young;Lee, Young-Ha
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.4
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    • pp.317-329
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    • 2002
  • Background : Immunotherapy is another treatment modality for various cancers. There is little information on the antitumor effects of immunotherapy on implanted lung cancer mouse models. Toxoplasma gondii is able to potently induce a nonspecific stimulation of the host immune system. Therefore, this study evaluated the antitumor and antimetastatic effect of nonspecific immune stimulation by T. gondii in a Lewis lung cancer mouse model. Methods : Female C57BL/6 mice were injected with either Lewis lung cancer cells ($1{\times}10^6$ per mouse) or 5 cysts from the T. gondii Me49 strain with various schedules. The number of survival days, the tumor size of the implanted muscle and the histopathological findings of each group were noted. In addition to these mice, the Toxoplasma antigen($50{\mu}g$ per mouse) or a lymphokine (0.5 ml per mouse) was added to boost the immunotherapy. Results : No mouse in the Toxoplasma-infected group had died, whereas the mice receiving only the cancer cells (cancer control) survived for $29.1{\pm}4.4$ days. Cancer cells were revealed from 1 week after cancer cell inceulation in the muscle and from 3 weeks in the lung of the cancer control, whereas cancer cells were found in both the preinfection control and coinfection control groups from 2 weeks and 4 weeks in the lung respectively. The in the number of survival days were $32.4{\pm}3.3$ in the mice receiving T. gondii 2 weeks prior to the cancer cells inoculation (preinfection control), $30.9{\pm}5.1$ in mice received both simultaneously (coinfection control), and $34.9{\pm}2.9$ in mice received T. gondii 2 weeks after cancer cells implantation (postinfection control). These 3 infection groups had significantly longer survival days and suppressed tumor growth than those of the cancer control. In addition to these mice, and injection with the Toxoplasma antigen alone or in combination with lymphokine resulted in a significant increase in the number of survival days. Conclusion : These findings suggest that an injection with T. gondii can induce the antitumor and antimetastatic effects in Lewis lung cancer mouse models. Moreover, these effects were increased with an injection of the Toxoplasma antigen alone or in combination with lymphokine. However, this therapy can not prevent the development of cancer.

Estimating Grain Weight and Grain Nitrogen Content with Temperature, Solar Radiation and Growth Traits During Grain-Filling Period in Rice (등숙기 온도 및 일사량과 생육형질을 이용한 벼 종실중 및 종실질소함량 추정)

  • Lee, Chung-Kuen;Kim, Jun-Hwan;Son, Ji-Young;Yoon, Young-Hwan;Seo, Jong-Ho;Kwon, Young-Up;Shin, Jin-Chul;Lee, Byun-Woo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.55 no.4
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    • pp.275-283
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    • 2010
  • This experiment was conducted to construct process models to estimate grain weight (GW) and grain nitrogen content (GN) in rice. A model was developed to describe the dynamic pattern of GW and GN during grain-filling period considering their relationships with temperature, solar radiation and growth traits such as LAI, shoot dry-weight, shoot nitrogen content, grain number during grain filling. Firstly, maximum grain weight (GWmax) and maximum grain nitrogen content (GNmax) equation was formulated in relation to Accumulated effective temperature (AET) ${\times}$ Accumulated radiation (AR) using boundary line analysis. Secondly, GW and GN equation were created by relating the difference between GW and GWmax and the difference between GN and GNmax, respectively, with growth traits. Considering the statistics such as coefficient of determination and relative root mean square of error and number of predictor variables, appropriate models for GW and GN were selected. Model for GW includes GWmax determined by AET ${\times}$ AR, shoot dry weight and grain number per unit land area as predictor variables while model for GN includes GNmax determined by AET ${\times}$ AR, shoot N content and grain number per unit land area. These models could explain the variations of GW and GN caused not only by variations of temperature and solar radiation but also by variations of growth traits due to different sowing date, nitrogen fertilization amount and row spacing with relatively high accuracy.

Effects of Dietary Tea Polyphenol on Tumor Growth Inhibition by Cisplatin in EMT6 Breast Tumor-bearing Mice (유방암 세포(EMT6) 이식 마우스에서 녹차폴리페놀 음용이 시스플라틴의 암 조직 성장 억제에 미치는 영향)

  • Lee, Byoung-Rai;Cho, Jung-Il;Park, Pyoung-Sim
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.1
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    • pp.47-54
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    • 2014
  • The aim of this study is to evaluate the effects of green tea polyphenol (GTP) on anticancer treatment with cisplatin (CP), using both an in vitro cell culture model and an in vivo mouse model of established breast tumor. Mouse breast cancer cells (EMT6) were treated with or without GTP and CP followed by determination of the cell viability using an MTT assay. The relative cell viability of CP treated EMT6 cells was 96% at a 20 ${\mu}g/mL$ concentration of cisplatin; however, in combination with GTP (50 ${\mu}g/mL$), the cell viability decreased to 20% at the same concentration of CP (20 ${\mu}g/mL$). For the in vivo study, EMT6 cells were inoculated into Balb/c mice for the establishment of a tumor-bearing mice model. The tumor-bearing mice were treated with CP (5 mg/kg. i.p.) with or without dietary GTP (0.2% drinking water). Tumor growth was monitored by a measurement of tumor size using a digital caliper, and nephrotoxicity was determined by enzymatic and histological examinations. The levels of p53 and caspase-3 in tumor tissues were examined by a Western blot. In tumor-bearing mice treated with GTP plus CP, the increment of tumor volume showed a significant reduction, compared with CP or GTP alone. The levels of p53 and cleaved caspase-3 (caspase-3/p17) in tumor tissues of tumor-bearing mice were increased by CP and GTP compared to CP alone. In CP treated tumor-bearing mice, ${\gamma}$-glutamyltranspeptidase (GGT) and alkaline phosphatase (AP) activities were decreased, and marked tubular necrosis and dilatation were observed in the kidney. CP-induced enzymatic and histopathological changes in the kidney of tumor-bearing mice were reduced by combinations of GTP with CP. The results of these experiments demonstrated that dietary GTP has a potentiating effect on CP anti-tumor activity and a protective effect against CP-induced renal dysfunction. Therefore, GTP may be used as a modulator in anticancer treatment with CP.

The Impact of Market Environments on Optimal Channel Strategy Involving an Internet Channel: A Game Theoretic Approach (시장 환경이 인터넷 경로를 포함한 다중 경로 관리에 미치는 영향에 관한 연구: 게임 이론적 접근방법)

  • Yoo, Weon-Sang
    • Journal of Distribution Research
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    • v.16 no.2
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    • pp.119-138
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    • 2011
  • Internet commerce has been growing at a rapid pace for the last decade. Many firms try to reach wider consumer markets by adding the Internet channel to the existing traditional channels. Despite the various benefits of the Internet channel, a significant number of firms failed in managing the new type of channel. Previous studies could not cleary explain these conflicting results associated with the Internet channel. One of the major reasons is most of the previous studies conducted analyses under a specific market condition and claimed that as the impact of Internet channel introduction. Therefore, their results are strongly influenced by the specific market settings. However, firms face various market conditions in the real worlddensity and disutility of using the Internet. The purpose of this study is to investigate the impact of various market environments on a firm's optimal channel strategy by employing a flexible game theory model. We capture various market conditions with consumer density and disutility of using the Internet.

    shows the channel structures analyzed in this study. Before the Internet channel is introduced, a monopoly manufacturer sells its products through an independent physical store. From this structure, the manufacturer could introduce its own Internet channel (MI). The independent physical store could also introduce its own Internet channel and coordinate it with the existing physical store (RI). An independent Internet retailer such as Amazon could enter this market (II). In this case, two types of independent retailers compete with each other. In this model, consumers are uniformly distributed on the two dimensional space. Consumer heterogeneity is captured by a consumer's geographical location (ci) and his disutility of using the Internet channel (${\delta}_{N_i}$).
    shows various market conditions captured by the two consumer heterogeneities.
    (a) illustrates a market with symmetric consumer distributions. The model captures explicitly the asymmetric distributions of consumer disutility in a market as well. In a market like that is represented in
    (c), the average consumer disutility of using an Internet store is relatively smaller than that of using a physical store. For example, this case represents the market in which 1) the product is suitable for Internet transactions (e.g., books) or 2) the level of E-Commerce readiness is high such as in Denmark or Finland. On the other hand, the average consumer disutility when using an Internet store is relatively greater than that of using a physical store in a market like (b). Countries like Ukraine and Bulgaria, or the market for "experience goods" such as shoes, could be examples of this market condition. summarizes the various scenarios of consumer distributions analyzed in this study. The range for disutility of using the Internet (${\delta}_{N_i}$) is held constant, while the range of consumer distribution (${\chi}_i$) varies from -25 to 25, from -50 to 50, from -100 to 100, from -150 to 150, and from -200 to 200.
    summarizes the analysis results. As the average travel cost in a market decreases while the average disutility of Internet use remains the same, average retail price, total quantity sold, physical store profit, monopoly manufacturer profit, and thus, total channel profit increase. On the other hand, the quantity sold through the Internet and the profit of the Internet store decrease with a decreasing average travel cost relative to the average disutility of Internet use. We find that a channel that has an advantage over the other kind of channel serves a larger portion of the market. In a market with a high average travel cost, in which the Internet store has a relative advantage over the physical store, for example, the Internet store becomes a mass-retailer serving a larger portion of the market. This result implies that the Internet becomes a more significant distribution channel in those markets characterized by greater geographical dispersion of buyers, or as consumers become more proficient in Internet usage. The results indicate that the degree of price discrimination also varies depending on the distribution of consumer disutility in a market. The manufacturer in a market in which the average travel cost is higher than the average disutility of using the Internet has a stronger incentive for price discrimination than the manufacturer in a market where the average travel cost is relatively lower. We also find that the manufacturer has a stronger incentive to maintain a high price level when the average travel cost in a market is relatively low. Additionally, the retail competition effect due to Internet channel introduction strengthens as average travel cost in a market decreases. This result indicates that a manufacturer's channel power relative to that of the independent physical retailer becomes stronger with a decreasing average travel cost. This implication is counter-intuitive, because it is widely believed that the negative impact of Internet channel introduction on a competing physical retailer is more significant in a market like Russia, where consumers are more geographically dispersed, than in a market like Hong Kong, that has a condensed geographic distribution of consumers.
    illustrates how this happens. When mangers consider the overall impact of the Internet channel, however, they should consider not only channel power, but also sales volume. When both are considered, the introduction of the Internet channel is revealed as more harmful to a physical retailer in Russia than one in Hong Kong, because the sales volume decrease for a physical store due to Internet channel competition is much greater in Russia than in Hong Kong. The results show that manufacturer is always better off with any type of Internet store introduction. The independent physical store benefits from opening its own Internet store when the average travel cost is higher relative to the disutility of using the Internet. Under an opposite market condition, however, the independent physical retailer could be worse off when it opens its own Internet outlet and coordinates both outlets (RI). This is because the low average travel cost significantly reduces the channel power of the independent physical retailer, further aggravating the already weak channel power caused by myopic inter-channel price coordination. The results implies that channel members and policy makers should explicitly consider the factors determining the relative distributions of both kinds of consumer disutility, when they make a channel decision involving an Internet channel. These factors include the suitability of a product for Internet shopping, the level of E-Commerce readiness of a market, and the degree of geographic dispersion of consumers in a market. Despite the academic contributions and managerial implications, this study is limited in the following ways. First, a series of numerical analyses were conducted to derive equilibrium solutions due to the complex forms of demand functions. In the process, we set up V=100, ${\lambda}$=1, and ${\beta}$=0.01. Future research may change this parameter value set to check the generalizability of this study. Second, the five different scenarios for market conditions were analyzed. Future research could try different sets of parameter ranges. Finally, the model setting allows only one monopoly manufacturer in the market. Accommodating competing multiple manufacturers (brands) would generate more realistic results.

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  • Monitoring Bacillus cereus and Aerobic Bacteria in Raw Infant Formula and Microbial Quality Control during Manufacturing (영.유아용 식품원료의 Bacillus cereus와 일반세균 모니터링 및 제조공정 중 미생물 품질제어)

    • Jung, Woo-Young;Eom, Joon-Ho;Kim, Byeong-Jo;Ju, In-Sun;Kim, Chang-Soo;Kim, Mi-Ra;Byun, Jung-A;Park, You-Gyoung;Son, Sang-Hyuck;Lee, Eun-Mi;Jung, Rae-Seok;Na, Mi-Ae;Yuk, Dong-Yeon;Gang, Ji-Yeon;Heo, Ok-Sun;Yoon, Min-Ho
      • Korean Journal of Food Science and Technology
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      • v.42 no.4
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      • pp.494-501
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      • 2010
    • The purpose of this study was to examine the presence of Bacillus cereus, aerobic bacteria and coliforms in the raw material of infant formulas and investigate the manufacturing process in terms of microbial safety. Among ten kinds of raw infant formula material samples (n=20), Bacillus cereus appeared in two (n=4). Aerobic bacteria were not detected in raw infant formula material or maximum 4.15 log CFU/g. Eleven species of aerobic bacteria were isolated and 76% of them were Sphingomonas paucimobilis, Pseudomonas fluorescens, Rhizobium radiobactor, or Stenotrophomonas maltophilia. A Pearson's correlation analysis revealed that the most influential factors for detecting Bacillus cereus were aerobic bacteria and coliforms. In other words, when the measured values of aerobic bacteria and coliforms were higher, the possibility that Bacillus cereus would appear increased. In a regression model to predict Bacillus cereus, the rate of appearance was correlated with aerobic bacteria and coliforms, and its contribution rate for effectiveness was 86%. Improving microbial quality control by pasteurization, spray dry, popping and extrusion resulted in a decrease in the numbers of Bacillus cereus, aerobic bacteria and coliforms in the raw materials. The results suggest that a hazard analysis and critical control point system might be effective for reducing microbiological contamination.

    Intratumoral Administration of Dendritic Cells Combined with Hyperthermia Induces Both Local and Systemic Antitumor Effect in Murine Tumor Models (온열 요법 후 종양 내 주입한 수지상 세포의 국소 및 원격 항종양 효과)

    • Kwon Byung-Hyun;Kim Won-Taek;Kim Young-Kan;Kim Dong-Won
      • Radiation Oncology Journal
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      • v.24 no.1
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      • pp.51-57
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      • 2006
    • Puroose: We examined whether intratumoral (i.t.) administration of dendritic cells (DCs) into a treated tumor could induce local and systemic antitumor effects in a mouse tumor model. Methods and Materials: C57BL/6 mice were inoculated s.c. in the right and left thighs with MCA-102 fibrosarcoma cells on day 0 and on day 7, respectively. On day 7, the tumors (usually 6 mm in diameter) on the right thigh were heated by immersing the tumor-bearing leg in a circulating water bath at $43^{\circ}C$ for 30 min; thereafter, the immature DCs were i.t administered to the right thigh tumors. This immunization procedure was repeated on days 7, 14 and 21. The tumors in both the right and left thighs were measured every 7 days and the average sizes were determined by applying the following formula, tumor $size=0.5{\times}(length+width)$. Cytotoxicity assay was done to determine tumor-specific cytotoxic T-lymphocyte activity. Results: Hyperthermia induced apoptosis and heat shock proteins (HSPs) in tumor occurred maximally after 6 hr. For the local treated tumor, hyperthermia (HT) alone inhibited tumor growth compared with the untreated tumors (p<0.05), and furthermore, the i.t. administered DCs combined with hyperthermia (HT + DCs) additively inhibited tumor growth compared with HT alone (p<0.05). On the distant untreated tumor, HT alone significantly inhibited tumor growth (p<0.05), and also HT + DCs potently inhibited tumor growth (p<0.001); however, compared with HT alone, the difference was not statistically significant. In addition, HT + DCs induced strong cytotoxicity of the splenocytes against tumor cells compared to DCs or HT alone. Conclusion: HT + DCs induced apoptosis and increased the expression of HSPs, and so this induced a potent local and systemic antitumor response in tumor-bearing mice. This regimen may be beneficial for the treatment of human cancers.

    The Simulation for the Organization of Fishing Vessel Control System in Fishing Ground (어장에 있어서의 어선관제시스템 구축을 위한 모의실험)

    • 배문기;신형일
      • Journal of the Korean Society of Fisheries and Ocean Technology
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      • v.36 no.3
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      • pp.175-185
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      • 2000
    • This paper described on a basic study to organize fishing vessel control system in order to control efficiently fishing vessel in Korean offshore. It was digitalized ARPA image on the fishing processing of a fleet of purse seiner in conducting fishing operation at Cheju offshore in Korea as a digital camera and then simulated by used VTMS. Futhermore, it was investigated on the application of FVTMS which can control efficiently fishing vessels in fishing ground. The results obtained were as follows ; (1) It was taken 16 minutes and 35 minutes to casting and hauling net in fishing processing respectively. The length of rope pulled by scout boat was 200m, tactical diameter in casting net was 340.8m, turning speed was 6kts as well. (2) The processing of casting and hauling net was moved to SW, NE as results of simulation when the current direction and speed set into NE, 2kts and SW, 2kts respectively. Such as these results suggest that can predict to control the fishing vessel previously with information of fishing ground, fishery and ship's maneuvering, etc. (3) The control range of VTMS radar used in simulation was about 16 miles. Although converting from a radar of the control vessel to another one, it was continuously acquired for the vector and the target data. The optimum control position could be determined by measuring and analyzing to distance and direction between the control vessel and the fleet of fishing vessel. (4) The FVTMS(fishing vessel traffic management services) model was suggested that fishing vessels received fishing conditions and safety navigation information can operate safely and efficiently.

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    Small Animal PET Imaging with [$^{124}I$]FIAU for Herpes Simplex Virus Type 1 Thymidine Kinase Gene Expression in a Hepatoma Model (간암 동물 모델에서 2'-fluoro-2'-deoxy-1-${\beta}$-D-arabinofuranosyl-5-[$^{124}I$iodo-uracil ($[^{124}I]FIAU$) 소동물 PET 영상 연구)

    • Chae, Min-Jeong;Lee, Tae-Sup;Kim, June-Youp;Woo, Gwang-Sun;Jumg, Wee-Sup;Chun, Kwon-Soo;Kim, Jae-Hong;Lee, Ji-Sup;Ryu, Jin-Sook;Cheon, Gi-Jeong;Choi, Chang-Woon;Lim, Sang-Moo
      • Nuclear Medicine and Molecular Imaging
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      • v.42 no.3
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      • pp.235-245
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      • 2008
    • Purpose: The HSV1-tk gene has been extensively studied as a type of reporter gene. In hepatocellular carcinoma (HCC), only a small proportion of patients are eligible for surgical resection and there is limitation in palliative options. Therefore, there is a need for the development of new treatment modalities and gene therapy is a leading candidate. In the present study, we investigated the usefulness of substrate, 2'-fluoro-2'-deoxy-1-${\beta}$-D-arabino-furanosyi-5-[$^{124/125}I$]iodo- uracil ([$I^{124/125}I$]FIAU) as a non-invasive imaging agent for HSV1-tk gene therapy in hepatoma model using small animal PET. Material and Methods: With the Morris hepatoma MCA cell line and MCA-tk cell line which was transduced with the HSV1-tk gene, in vitro uptake and correlation study between [$^{125}I$]FIAU uptake according to increasing numeric count of percentage of MCA-tk cell were performed. The biodistribution data and small animal PET images with [$^{124}I$]FIAU were obtained with Balb/c-nude mice bearing both MCA and MCA-tk tumors. Results:, Specific accumulation of [[$^{125}I$]FIAU was observed in MCA-tk cells but uptake was low in MCA cells. Uptake in MCA-tk cells was 15 times higher than that of MCA cells at 480 min. [$^{125}I$]FIAU uptake was linearly correlated (R2 =0.964, p =0.01) with increasing percentage of MCA-tk numeric cell count. Biodistribution results showed that [$^{125}I$]FIAU was mainly excreted via the renal system in the early phase. Ratios of MCA-tk tumor to blood acting were 10, 41, and 641 at 1 h, 4 h, and 24 h post-injection, respectively. The maximum ratio of MCA-tk to MCA tumor was 192.7 at 24 h. Ratios of MCA-tk tumor to liver were 13.8, 66.8, and 588.3 at 1 h, 4 h, and 24 h, respectively. On small animal PET, [$^{124}I$]FIAU accumulated in substantial higher levels in MCA-tk tumor and liver than MCA tumor. Conclusion: FIAU shows selective accumulation to HSV1-tk expressing hepatoma cell tumors with minimal uptake in normal liver. Therefore, radiolabelled FIAU is expected to be a useful substrate for non-invasive imaging of HSV1-tk gene therapy and therapeutic response monitoring of HCC.


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