• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.231-236
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• 2001

How much do we know about the biology of aging from cell culture studies Most normal somatic cells have a finite potential to divide due to a process termed cellular or replicative senescence. A growing body evidence suggests that senescence evolved to protect higher eu-karyotes, particularly mammals, from developing cancer, We now know that telomere shortening due to the biochemistry of DNA replication, induces replicative senescence in human cells. How-ever in rodent cells, replicative senescence occurs despite very long telomeres. Recent findings suggest that replicative senescence is just the tip of the iceberg of a more general process termed cellular senescence. It appears that cellular senescence is a response to potentially oncogenic in-sults, including oxidative damage. In young orgainsms, growth arrest by cell senescence sup-presses tumor development, but later in life, due to the accumulation of senescent cells which se-cret factors that can disrupt tissues during aging, cellular senescence promotes tumorigenesis. Therefore, antagonistic pleiotropy may explain, if not in whole the apparently paradoxical effects of cellular senescence, though this still remains an open question.

• Journal of Electrical Engineering and Technology
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• v.2 no.3
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• pp.312-319
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• 2007

The solution of the power flow is one of the most important problems in electrical power systems. These traditional methods such as Gauss-Seidel method and Newton-Raphson (NR) method have had drawbacks up to now such as initial values, abnormal operating solutions and divergences in heavy loads. In order to overcome theses problems, the power flow solution incorporating genetic algorithm (GA) is introduced in this paper. General operator of genetic algorithm, arithmetic crossover, and non-uniform mutation operator of GA are suggested to solve the power flow problem. While abnormal solution cannot be obtained by a NR method, multiple power flow solution can be obtained by a GA method. With a heavy load, both normal solution and abnormal solution can be obtained by a proposed method. In this paper, a floating number representation instead of the binary number representation is introduced for accuracy. Simulation results have been compared with traditional methods.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.698-701
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• 2007

DAHAN, the first 1 MWe Solar Power Tower system locates north to Beijing where nearby The Great Wall is now under construction with cooperation between China and Korea. Results in predicting the preliminary performance of this central receiver system are presented in this paper. Operating cycles under some typical weather condition days are simulated and commented. These results can be used to assess the impact of alternative plant designs or operating strategies on annual energy production, with the final objective being to optimize the design of central receiver power plants. Two subsystems are considered in the system simulation: the solar field and the power block. Mathematic models are used to represent physical phenomena and relationships so that the characteristics of physical processes involving these phenomena can be predicted. Decisions regarding the best position for locating heliostats relative to the receiver and how high to place the receiver above the field constitute a multifaceted problem. Four different kinds of field layout are designed and analyzed by the use of ray tracing and mathematical simulation techniques to determine the overall optical performance ${\eta}_{field}$ and the spillage ${\eta}_{spill}$.The power block including a Rankine cycle is analyzed by conventional energy balance methods.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.80-80
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• 1997

The object of this study was to develop a gene therapy strategy for ovarian cancer. We have previously shown that AV with a L-plastin (LP) promoter infects breast and ovarian cancer cells and expressed ${\beta}$-galactosidase cDNA in preference to normal fibroblast cells and hematopoietic cells. We now report on the cytotoxicity of Ad.LP.CD, an AV carrying a CD cDNA which converts the pro-drug, 5-Fluorocytosine (5-FC) into the toxic drug 5-Fluorouracil (5-FU). Infection of Ad.LP.CD into either 293 cells or ovarian cancer cells generated the functional CD as measured by HPLC analysis. Using a ratio of AV to OVCAR3 cell of 100 and a 5-FC concentration of 100 ${\mu}$M, we achieve an over 95 % of cell growth inhibition. We are using flow cytometry analysis for ${\beta}$ -galactosidase and ovarian cancer associated folate receptor to screen primary ascites samples for infectivity after infection with an adenoviral vector, i.e., Ad.LP.LacZ. This vector system may be of value in the treatment of microscopic disease of ovarian cancer in the peritoneal cavity.

• Journal of Chest Surgery
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• v.7 no.2
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• pp.169-174
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• 1974

Duplication of the alimentary tract, especially of the esophagus, have been regarded as rare cong- enital anomalies. However, they are being reported with increasing frequency in the literature. In the . ,- past they have been described by a variety of names, such as "enteric cysts", "intestinal cysts", "giant diverticula", "`mediastinal cysts of foregut origin" "enterogenous cysts" and other descriptive terms. . Most authorities now agree that these anomalies are best described by the term "duplications of the alimentary tract. The duplications [of the alimentary tract] are spherical or tubular structures which poses a well developed smooth muscle layer and are lined with a mucous membrane from any part of the alimentary tract. They may occur at any place in the digestive tube from the tongue to the rectum and usually are intimately attached to some portion of the alimentary tube. We have experienced a duplication of the esophagus in 14 years old middle schoolboy. He complained dysphagia, eructation and substernal pain associated with intermittent high fever and chilliness, increasing in severity for recent three weeks. Routine chest X-ray film revealed nore markable abnormal finding but esophagogram. revealed marked narrowing of the esophagus throughout with a large blind pouch in lower half with fistulous communication at mid portion of the esophagus. On thoracotomy, a large infected blind pouch communicating with the lumen of normal esophagus proximally, Was extended from the level of 5th to 10th thoracic spine. The duplicated segment of the esophagus has a common muscular .wall and proximal communication with the adjacent esophagus. The infected, duplicated esophagus was segmentally resected, and esophagogastrostomy with pyloroplasty was done by displacing the stomach into the right thoracic cavity through midline laparotomy. His Postoperative course was uneventful and discharged without complication.

• Economic and Environmental Geology
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• v.28 no.2
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• pp.165-176
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• 1995

Dongrae is one of the most famous hot spring resort area in the Republic of Korea. The water temperature ranges $50^{\circ}C{\sim}66$. The chemical composition of the thermal water is quite different from normal groundwater. $Na^+$ and $Cl^-$ are the main components, measured more than 75%, $Ca^{+{+}}$ is contained about 22% and the other ions such as $SO_4$ or $HCO_3$ are the minor components. The heat source is uprising along the fracture zone of granite which is indicated as a subsurface high temperature belt. During the research period of 1991~1992, the groundwater table was lowered down to the depth of about 100 m according to continuous increase of daily use of thermal water. The groundwater table was fluctuated with an amplitude of day, weak or seasion. The groundwater table was the lowest at 18:00 h in a day and also lowest at the weekend for the week period. There was a relavent relationship between drawdown and the amount of thermal water use on a long term base. To protect such a rapid drawdown of groundwater table, Dongrae resort area is now asked to take strong municipal control for the daily use of thermal water.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.9 no.1
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• pp.5-13
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• 2001

There are many studies which reveal most of the accidents are related to pilot errors. Looking at each phase of flight, the accidents which occurred at the segments of take-off and landing consist of 70%, cause these phases need precise cooperations between pilots and ATC specialists to make sure every instructions understood and instruments to be normal. Therefore, the accidents of these phases leave great regrets and the price was enormous to people and equipments. Until now, most of the studies investigate the accident itself and very few show the relationships between pilots and air traffic controllers. This study analyzes the impacts of inter-dependence to mutual trust, cooperations and relationship efficiency between them who play important parts in flight. Based upon the findings, the inter-dependence has an effect on mutual trust and the latter influences to cooperations. Also, mutual trust and cooperations have a leading role in the relationship efficiency. It implies that mutual trust, cooperations, and the degree of inter-dependence are important factors to improve the relationships between them.

• Journal of Korean Traditional Oncology
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• v.12 no.1
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• pp.15-24
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• 2007

Objective: We have the purpose of evaluating the effects of lymphatic massage on lymphoedema in breast cancer patients. Method: The patient who has in condition of lymphoedema after the breast cancer therapy is taken massages with aroma oil for 5 days. We measured the upper arm circumference and edema index before and after the therapy. We also measure the edema index of normal arm to compare with the abnormal one. Results: We gave 4 patients the decongestive lymphatic therapy and now present the positive conclusion. 3cases of the 4 showed decrease of circumferences and edema index. It means that the edematous condition getting better during these therapy. Conclusion: Lymphatic massage with aroma therapy may have effectiveness on lymphoedema in breast cancer patients. but further advanced clinical trials are needed.

• The Journal of Pediatrics of Korean Medicine
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• v.23 no.1
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• pp.85-93
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• 2009

Objectives The purpose of this study is to report a case which gave various remarkable epilepsy treatment results by using oriental medicine. Methods We treated the patient with acupuncture as a main treatment and herbal medicine. We also recommended to the patient and patient's parents to continue oriental medical treatment for 2 years from now because symptomatic epilepsy is a type of disease which needs long term care. Results The epileptic seizure has been well controlled for 12 months so far, and the results was recorded by EEG. The EEG level was in normal range. Conclusions Even though this is only one case of the study but this case has an important meaning because the epilepsy was treated by oriental medicine, especially acupuncture treatment. The control of the symptomatic epileptic seizure was effective by means of increasing patient's quality of life. Further studies about effective treatment of symptomatic epilepsy would be needed with more various cases.

• Clinical and Experimental Pediatrics
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• v.54 no.2
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• pp.86-89
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• 2011

Traumatic ventricular septal defect (VSD) resulting from blunt chest injury is a very rare event. The mechanisms of traumatic VSD have been of little concern to dateuntil now, but two dominant theories have been described. In one, the rupture occurs due to acute compression of the heart; in the other, it is due to myocardial infarction of the septum. The clinical symptoms and timing of presentation are variable, so appropriate diagnosis can be difficult or delayed. Closure of traumatic VSD has been based on a combination of heart failure symptoms, hemodynamics, and defect size. Here, we present a case of a 4-year-old boy who presented with a traumatic VSD following a car accident. He showed normal cardiac structure at the time of injury, but after 8 days, his repeated echocardiography revealed a VSD. He was successfully treated by surgical closure of the VSD, and has been doing well up to the present. This report suggests that the clinician should pay great close attention to the patients injured by blunt chest trauma, keeping in mind the possibility of cardiac injury.