• The korean journal of orthodontics
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• v.31 no.1 s.84
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• pp.107-120
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• 2001

Nitric oxide(NO) has been reported to be one of the mediators relating to bone remodelling. Nitric oxide is synthesized from L-arguinine by nitric oxide synthetase(NOS), which is largely divided Into two groups. One group which is composed of $NOS_1\;and\;NOS_3$, is dependent of calcium or calmodulin. The other consisted of $NOS_2$, which is independent of calcium or calmodulin. NOS is thought to be a possible intermediate affecting in the course of tooth movement. This study was designed to evaluate the expression of nitrous oxide synthetase(NOS) in periodontal tissue during the experimental movement of rat incisors, by LSAB(labelled streptavidine biotin) immunohistochemical staining for $NOS_2\;and\;NOS_3$. Twenty seven Sprague-Dawley rats were divided into a control group(3 rats), and 6 experimental groups(24 rats), to which 75g of force was applied, with helical springs across the maxillary incisors. Rats of experimental groups were sacrificed at 12 hours, 1, 4, 7, 14 and 28 days after force application, respectively. After that, the tissues of the control group and experimental groups were studied immunohistochemically. The results were as follows: 1. In control group, the expression of $NOS_3$ was rare in gingiva, dentin, periodontal ligament and alveolar bone, and was mild in the capillaries of pulp and intermaxillary suture. And the expression of $NOS_2$ showed similar pattern to that of $NOS_3$. 2. There were no differences in the expression of $NOS_2\;or\;NOS_3$ in dentin, gingiva, cementum, cementoblast and odontoblast, between control and experimental groups, regardless of the duration of the force application. 3. The expression of $NOS_3$ began to increase at 4 days and showed to the highest degree at 7 days after force application, in the apical region of pressure side of periodontal ligament in experimental groups. 4. The expression of $NOS_3$ in alveolar bone was rare until 7 days, after which it increased to mild degree at 14 days through 28 days in experimental group. But there was no difference between pressure and tension side of periodontal ligament. 5. The expression of $NOS_2$ in periodontal ligament was mild from 7 days after force application, regardless of the side of periodontium, which was generally more evident than that of $NOS_3$. 6. The expression of $NOS_2$ in alveolar bone increased to mild degree at 14 days after force application, and it was evident in osteoblasts, osteoclasts and osteocytes. And the expression of $NOS_2$ was little more stronger in the tension side than that of pressure side of alveolar bone.

• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.153-164
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• 1999

The solubilization of BTEX was evaluated in aqueous surfactant solutions with and without several additives. Anionic surfactant(Sodium Dodecyl Sulfate, SDS) and nonionic surfactants (NEODOL(equation omitted)25-3 and $SOFTANOL\circledR-90$ were used as test surfactants. The effects of surfactant HLB(Hydrophile-Lipophile Balance) Number and hydrocarbon molar volume and polarity of BTEX on the MSR(Molar Solubilization Ratio), micelle-water partition coefficient of BTEX, and CMC(C,itical Micelle Concentration) were investigated. Optimizing treatment conditions applicable to enhanced solubilization was also studied by manupulating salinity or electrolyte control with additives of ethyl alcohol, hydrotrope, and electrolyte solution. The most effective surfactant for solubilization was found $SOFTANOL\circledR-90$, since HLB number of 13.6 is similar to those values of BTEX ranging between 11.4 and 12.2, which was also proved experimentally. Ethyl alchohol of 3% was the most effective additives in reducing CMC and improving solubilization among the conditions using SDS, NEODOL(equation omitted)25-3, and $SOFTANOL\circledR-90$ with three additives. The partitioning of BTEX between surfactant micelles and aqueous solutions was characterized by a mole fraction micelle-phase/aqueous phase partion coefficient, $K_m$. Values of log $K_m$. for BTEX compounds in surfactant solutions of this study range from 2.95 to 3.76(100mM SDS) and 2.95 to 3.49(117mM $SOFTANOL\circledR-90$. Log $K_m$ appears to be a linear function of log $K_{ow}$ for SDS and $SOFTANOL\circledR-90$. A knowledge of partitioning of BTEX in aqueous surfactant system can be a prerequisite for the understanding of the behavior of hydrophobic organic compounds in soil-water systems in which surfactants play a role in remediation of contaminated soil and facilitated transport.

• Journal of Intelligence and Information Systems
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• v.22 no.4
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• pp.177-192
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• 2016

Machine learning is a field of artificial intelligence. It refers to an area of computer science related to providing machines the ability to perform their own data analysis, decision making and forecasting. For example, one of the representative machine learning models is artificial neural network, which is a statistical learning algorithm inspired by the neural network structure of biology. In addition, there are other machine learning models such as decision tree model, naive bayes model and SVM(support vector machine) model. Among the machine learning models, we use SVM model in this study because it is mainly used for classification and regression analysis that fits well to our study. The core principle of SVM is to find a reasonable hyperplane that distinguishes different group in the data space. Given information about the data in any two groups, the SVM model judges to which group the new data belongs based on the hyperplane obtained from the given data set. Thus, the more the amount of meaningful data, the better the machine learning ability. In recent years, many financial experts have focused on machine learning, seeing the possibility of combining with machine learning and the financial field where vast amounts of financial data exist. Machine learning techniques have been proved to be powerful in describing the non-stationary and chaotic stock price dynamics. A lot of researches have been successfully conducted on forecasting of stock prices using machine learning algorithms. Recently, financial companies have begun to provide Robo-Advisor service, a compound word of Robot and Advisor, which can perform various financial tasks through advanced algorithms using rapidly changing huge amount of data. Robo-Adviser's main task is to advise the investors about the investor's personal investment propensity and to provide the service to manage the portfolio automatically. In this study, we propose a method of forecasting the Korean volatility index, VKOSPI, using the SVM model, which is one of the machine learning methods, and applying it to real option trading to increase the trading performance. VKOSPI is a measure of the future volatility of the KOSPI 200 index based on KOSPI 200 index option prices. VKOSPI is similar to the VIX index, which is based on S&P 500 option price in the United States. The Korea Exchange(KRX) calculates and announce the real-time VKOSPI index. VKOSPI is the same as the usual volatility and affects the option prices. The direction of VKOSPI and option prices show positive relation regardless of the option type (call and put options with various striking prices). If the volatility increases, all of the call and put option premium increases because the probability of the option's exercise possibility increases. The investor can know the rising value of the option price with respect to the volatility rising value in real time through Vega, a Black-Scholes's measurement index of an option's sensitivity to changes in the volatility. Therefore, accurate forecasting of VKOSPI movements is one of the important factors that can generate profit in option trading. In this study, we verified through real option data that the accurate forecast of VKOSPI is able to make a big profit in real option trading. To the best of our knowledge, there have been no studies on the idea of predicting the direction of VKOSPI based on machine learning and introducing the idea of applying it to actual option trading. In this study predicted daily VKOSPI changes through SVM model and then made intraday option strangle position, which gives profit as option prices reduce, only when VKOSPI is expected to decline during daytime. We analyzed the results and tested whether it is applicable to real option trading based on SVM's prediction. The results showed the prediction accuracy of VKOSPI was 57.83% on average, and the number of position entry times was 43.2 times, which is less than half of the benchmark (100 times). A small number of trading is an indicator of trading efficiency. In addition, the experiment proved that the trading performance was significantly higher than the benchmark.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.3
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• pp.217-229
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• 2010

Objective: Apoptosis plays an important role for the maintenance of the normal pregnancy. Expression of X-linked inhibitor of apoptosis (XIAP) is able to effectively prevent apoptosis and controls trophoblast cells death throughout placental development, but it is still unknown in the function of XIAP in trophoblast cells exposed to hypoxic condition, which is one of the factors causing preeclampsia. Therefore, we conducted to compare XIAP expression in normal and pre-eclamptic placenta tissues and analyzed the function of XIAP in HTR-8/SVneo trophoblast cell line exposed to hypoxic condition. Methods: The expression of XIAP was analyzed in placental tissues from the following groups of patients (none underwent labor): 1) term normal placenta (n=15); 2) term with pre-eclamptic placeneta (n=15); and 3) pre-term with pre-eclamptic placenta (n=11) using semi-quantitative RT-PCR, immunohistochemistry, and Western blot. In order to evaluate the function of XIAP in HTR-8/SVneo trophoblast cells under hypoxic condition, HIF-$1{\alpha}$ plasmids, and hypoxic condtion were transfected and treated into HTR-8/SVneo trophoblast cells for 24 hours, respectively. Results: We observed that XIAP are expressed in the syncytiotrophoblasts and syncytial knot of placental villi. The expression of XIAP was significantly decreased in preeclamptic placenta tissues than in normal placenta tissues without labor (p<0.05). Furthermore, we confirmed the XIAP expression in HTR-8/SVneo trophbolast cells exposed to hypoxia was translocated from cytoplasm into nucleus and decreased XIAP by hypoxic condition induced apoptosis in HTR-8/SVneo trophoblast cells through up-regulation of pro-apoptotic proteins. Conclusion: These results suggest that the expression of XIAP is involved in placental development as well as decreased expression of XIAP by hypoxia is associated with pre-eclampsia through inducing trophoblast cells apoptosis.

• Journal of Life Science
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• v.17 no.11
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• pp.1576-1581
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• 2007

Dopamine reward pathway projecting from ventral tegmental area to nucleus accumbens is well known as playing an important role in alcohol dependence. It is supposed that this dopamine pathway is modulated by $5-HT_3$ nervous system, and it was reported that ondansetron (OND), $5-HT_3$ receptor antagonist, reduced drinking amount and increased abstinence rate in alcohol-dependent patients. The purpose of this study is to investigate the effect of combination of OND and naltrexone (NTX), non-specific opioid receptor antagonist, on alcohol intake in C57BL/6 mice. In 40 C57BL/6 mice in the state of alcohol dependence, vehicle, while OND 0.01 mg/kg, or NTX 1.0 mg/kg administrated respectively, or OND 0.01 mg/kg and NTX 1.0 mg/kg administrated simultaneously for ten days, medication effects on 2-hr alcohol, 22-hr water, 24-hr food intake and body weight were studied. When vehicle group was compared with 3 medication groups respectively, using a repeated measure ANOVA, NTX alone and vehicle groups showed a significant medication by time interaction (p=0.042) in 2-hr alcohol intake, but in the other 2 groups, OND and NTX combination group and OND alone group, there was no significant interaction with vehicle group in 2-hr alcohol intake. From these results, it is suggested that there is no effect on alcohol intake in mice treating with OND, and naltrexone#s suppression effect on alcohol intake in mice is attenuated when treating with OND and NTX simultaneously. It is supposed that a further study looking at the interactions of serotonin, dopamine and opioid nerves systems will be needed.

• Journal of Life Science
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• v.21 no.1
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• pp.119-126
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• 2011

There is a growing recognition of the significance of $H_2S$ as a biological signaling molecule involved in vascular and nervous system functions. In mammals, two enzymes in the transsulfuration pathway, cystathionine ${\beta}$-synthase (CBS) and cystathionine ${\gamma}$-lyase (CGL), are believed to be chiefly responsible for $H_2S$ biogenesis. Genetic inborn error of CGL leads to human genetic disease, cystathioninuria, by accumulating cystathionine in the body. This disease is secondarily associated with a wide range of diseases including diabetes insipidus and Down's syndrome. Although the human CGL (hCGL) overexpression is essential for the investigation of its function, structure, reaction specificity, substrate specificity, and protein-protein interactions, there is no clear report concerning optimum overexpression conditions. In this study, we report a detailed analysis of the overexpression conditions of the hCGL using a bacterial system. Maximum overexpression was obtained in conditions of low culture temperature after inducer addition, performing low aeration during overexpression, and using a low concentration inducer (0.1 mM, IPTG) for induction. Expressed hCGL was purified by His-tag affinity column chromatography and confirmed by Western blot using hCGL antibody and enzyme activity analysis. We also report that the His tag with TEV site attached protein exhibits 76% activity for ${\alpha}-{\gamma}$ elimination reaction with L-cystathionine and 88% for ${\alpha}-{\beta}$ elimination reaction with L-cysteine compared to those of wild type hCGL, respectively. His tag with TEV site attached protein also exhibits a 420 nm absorption maximum, which is attributed to the binding cofactor, pyridoxal 5'-phosphate (PLP).

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.2
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• pp.144-149
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• 2018

The eggs are incubated for 18 days through the generator and incubated in the developing incubator. During the developmental period, the weight loss of the fetus is correlated with the ventricular formation, and the proper ventricular formation is also associated with the healthy embryonic hatching and the egg hatching rate. However, in the incubator period of the domestic hatchery, it is a reality to acquire the resultant side by the Iranian standard weight measurement with the experience of the hatchery and the person concerned and the development period without the apparatus for measuring the present weight. As a result, prevalence of early mortality, hunger and illness during hatching are frequent. Monitoring the reduction of weaning weight is crucial to obtaining chick quality and hatching performance with weight changes within the development machine. Water loss is different depending on the size of eggs, egg shell, and elder group. We can expect to increase the hatching rate by measuring the weight change in real time and optimizing the ventilation change accordingly. There is a need to develop a real-time measurement system that can control 10 to 13% reduction of the total weight during hatching. The system through this study is a way to check the one - time directly when moving the existing egg, and it is impossible to control the measurement of the fetal water evaporation within the development period. Unlike systems that do not affect the hatching rate, four load cells are connected in parallel on the Arduino sketch board and the AT-command command is used to connect the mobile phone and computer in real time. The communication speed of Bluetooth was set to 15200 to match the communication speed of Arduino and Hyper-terminal program. The real - time monitoring system was designed to visually check the change of the weight of the fetus in the artificial incubator. In this way, we aimed to improve the hatching rate and health condition of the hatching eggs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.41-48
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• 1965

This study was aimed at knowing the magnitude of year variation in rice heading dates under the different seasonal cultures, and to estimate the heading date in advance. Using six rice varieties such as Kwansan, Suwon＃82, Suwon ＃144, Norin＃17, Yukoo＃132 and Paltal, the early, ordinary and late seasonal cultures had been carried out at Paddy Crop Division, Crop Experiment Station at Suwon for the six-year period 1959 to 1964. In addition the data of the standard rice cultures at the Provincial Offices of Rural Development for the 12-year period 1953 to 1954, were analyzed for the purpose of clarifying a relationship between variation of rice heading dates and some of meteorological data related to the locations and years. The results of this study are as follows: 1. Year variation of rice heading dates was as high as 14 to 21 days in the early seasonal culture and 7 to 14 days in the ordinary seasonal culture, while as low as one to seven days in the late seasonal culture which was the lowest among three cultures. The magnitude of variation depended greatly on variety, cultural season and location. 2. It was found out that there was a close negative correlation between the accumulated average air temperature for 40 days from 31 days after seeding and number of days to heading in the early seasonal culture. Accordingly, it was considered possible to predict the rice heading date through calculation of the accumulated average air temperature for the above period and then the linear regression(Y=a+bx). On the other hand, an estimation of the heading date in the late seasonal culture requires for the further studies. In the ordinary seasonal culture, no significant correlation between the accumulated average air temperature and number of days to heading was obtained in the six-year experiments conducted at Suwon. There was a varietal difference in relationship between the accumulated average air temperature for 70 days from seeding and number of days to heading in the standard cultures at the provincial offices of rural development. Some of varieties showed a significant correlation between two factors while the others didn't show any significant correlation. However, there was no regional difference in this relationship.

• Journal of Chest Surgery
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• v.31 no.9
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• pp.867-872
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• 1998

Background: The fixed dose regimen with activated coagulation time(ACT) is the most commonly employed method for determining the required dosage of heparin and protamine during cardiopulmonary bypass(CPB). Material and Method: We performed a prospective study on a fixed dose regimen for analyzing adequate dosages of heparin and protamine, the incidence of heparin resistance and heparin-induced thrombocyt openia, factors affecting ACT during CPB, and changes of ACT during aprotinin usage. 300 units/kg of heparin were administered to patients, and ACTs were measured after 5 mins. ACTs were checked at 10 mins and 30 mins after the onset of CPB, and then at 30 min intervals thereafter. If the measured ACT was under 400 secs, we added 100 units/kg of heparin. The heparin was reversed with 1 mg of protamine for each 100 units administered. If the measured ACT was longer than 130 secs 30 mins after protamine administration or if there was definitive evidence of a coagulation defect, we administered a further 0.5 mg/kg of protamine. Result: We studied 80 patients(50 adults and 30 children) who underwent open heart surgery(OHS) at Seoul National University Hospital. Preoperative ACT was 114.3${\pm}$19.3 secs in adults, and 119.5${\pm}$18.2 secs in children. There were no differences in preoperative ACT due to age, body weight, body surface area, or sex. The preoperative ACT was not influenced by a positive past history of OHS. Ten adults(20%) and 3 pediatric patients(10%) needed additional doses of heparin to maintain the ACT above 400 secs. Additional protamine administration was needed in 9 adults(18%) and 10 children(33%). Heparin resistance was found in only two adults. Heparin-induced thrombocytopenia was detected in 2 adults and 1 child. During CPB, ACT was prolonged. 12 adult patients received a low dose of aprotinin and showed longer celite activated ACT compared to the control group.The kaolin activated ACT showed a lower tendency than the celite activated ACT in aprotinin users. Conclusion: In conclusion, fixed dose regimen of heparin and protamine can be used without significant problems, but the incidence of need of additional dosage remains unsatisfactory.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.806-812
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• 1999

Background: Selection of reconstruction route in esophageal cancer surgery is based on the patient's status, characteristics of tumor, surgeon's preference and experience. Of the various routes, it has been documented that subcutaneous or substernal route may prolong operation time and may be vulnerable to postoperative respiratory complications. This study was designed to evaluate whether the selection of reconstruction route affects the surgical outcomes. Material and Method: Of 131 patients who have undergone resection and reconstruction for esophageal cancer, posterior mediastinal route(Group I, n=34), substernal route (Group II, n=31), and subcutaneous route(Group III, n=21) were retrospectively reviewed in 86 patients. Results of early operations and morbidities were compared between the groups. Result: There was a male prevalence(79 of males vs. 7 of females). There were 81 squamous cell cancers and 5 adenocarcinomas. There were no differences between groups in weight, height, age, cancer staging and location, and in the preoperative anesthetic risk evaluation and pulmonary function test(p=NS). Postoperative mechanical ventilation time was longer in Group I(20.6 hours) than in Group II(7.8 hours) or III(3.4 hours)(p=0.005). Duration of stay in the intensive care unit was prolonged in Group III(6.4 days) compared to Group I (3.9 days) or II(3.1 days)(p=0.043). No differences were noted in the duration of hospital stay between the groups(p=NS). Blood transfusion was needed in 30 out of 34 patients in Group I compared to 14/31 in Group II or 15/21 in Group III(p=0.001). The mean amount of transfusion for each patient was also higher in Group I(3,833 mL) than in Group II(1535 mL) or Group III(1419 mL)(p=0.04), but there was no difference in the inreoperation due to bleeding. Ea ly mortality rate was substantially higher in Group I(17.6%) but the differences between the groups were insignificant(p=NS). Although sepsis was a more prevalent cause of death in Group I, it was not related to anastomotic leak. Other morbidities did not differ between the groups(p=NS). Conclusion: In above results show that the reconstruction route does not affect the outcome of esophageal cancer surgery. We believe that the selection of reconstruction route can be based on the surgeon's preference and experience.