• Journal of Chest Surgery
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• v.15 no.1
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• pp.27-34
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• 1982

Pulmonary sequestration Is an unusual congenital malformation characterized by the presence of nonfunctioning lung tissue which usually has no communication with the normal bronchial tree and which receives its blood supply from an anomalous systemic artery instead of a pulmonary arterial branch. Two forms of pulmonary sequestration occur: Intralobar sequestration, in which the abnormal pulmonary tissue is incorporated within the normal lung and shares a common covering of visceral pleura, and extralobar sequestration, in which the abnormal pulmonary tissue is separated from the normal lung and has its own pleural investment. Since 1970, five cases of pulmonary sequestration were operated at the Department of Thoracic and Cardiovascular Surgery, College of Medicine, Seoul National University. 1. Among five cues, one was male and the others were female. 2. All were intralobar type and involved left lower lobe. 3. There was no operative mortality following left lower lobectomy and ligation of the aberrant artery.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.340-343
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• 2003

Soils contaminated by hazardous hydrophobic organic compounds, such as polycyclic aromatic hydrocarbons (PAHs), have become a major environmental issue due to toxic and carcinogenic properties of those compounds. In this work, we investigated effects of various metabolic inducers on phenanthrene biodegradation. Biodegradation tests were peformed with two different Pseudomonads: Pseudononrdia hydrocarboxydans (Gram positive) and Pseudomonas putida (Gram negative). Intermediates of phenanthrene metabolism (1-hydroxy-2-naphthoate, salicylate, catechol, phthalate and protocatechuate) were selected as inducers. The tests indicated that 1-hydroxy-2-naphthoate was the most effective inducer and enhanced the phenanthrene degradation rate up to 5.7 times, even though all the others also had induction ability to some extent. The effective induction could be achieved even at a low concentration of 1-hydroxy-2-naphthoate. Addition of metabolic inducers would be an attractive trick for the successful bioremediation of PAH-contaminated soil.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.471-476
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• 2000

Long-term behavior of reinforced clayey soil by model tests were performed to investigate the effect of reinforcement during loads and under static loads. In order to determine proper contents by weight of monofilament polypropylene fiber and calcium carbonate, the drying shrinkage and compressive strength tests had been conducted before model tests. Model tests were run on a clayey soil mixed with or without reinforcement and test specimen in test apparatus was placed in air dry for 7days before load application. In the case of fiber reinforced soil, the horizontal strain was lower than others during loads because the presence of fibers increased the soil's resistance to deformation. All of reinforced clayey soil, horizontal strain decreased as the water content decrease under static loads.

• Korean journal of aerospace and environmental medicine
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• v.30 no.1
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• pp.25-29
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• 2020

Space exploration is one of the dreams of humankind. However, the intriguing environment was a challenge for the human body, where we must counter with many extreme conditions such as thermal support, radiation, microgravity. Life, as well as the human body, developed and evolved in the continuous presence of gravity, especially when living creatures transfer from the ocean to the land. Once this gravitational force doesn't impact on the body, the drastic changes occur. Some of these changes were observed immediately, while others progress only slowly. Since the first orbital flight was performed, several hazards for the organs of the human body were identified [1]. These changes in human physiology can reverse when astronauts return to Earth. This article will review the published findings of the effects of microgravity exposure on the human body.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.513-518
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• 1995

To evaluate bile salt-tolerance of lactic acid bacteria (LAB, Lactobacillus acidophilus ATCC 4356, Lactobacillus casei IFO 3533, Streptococcus thermnophilus KCTC 2185, Lactobacillus lactis ATCC 4797, and Lactobacillus bulgaricus ATCC 11842), We investigated the survivals, acid production and $\beta $-galactosidase activity of LAB under anaerobic broth system. Cellular permeability of LAB and their cellular retention of $\beta $-galactosidase were also examined in the same system. Although the growth of LAB was slightly suppressed by 0.3% bile salt, they showed normal growth curve. Streptococcus thermophilus KCTC 2185 was significantly more resistant to bile salt than the others. The $\beta $-galactosidase activity from Streptococcus thermophilus KCTC 2185 and Lactobacillus bulgaricus ATCC 11842 and their cellular retention of $\beta $-galactosidase decreased by 0.3% bile salt. The cellular permeability of LAB in the presence of bile salt increased significantly.

• KSBB Journal
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• v.22 no.4
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• pp.185-190
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• 2007

Productivity of secreted recombinant protein depends largely on its stability in the extracellular environment with protease. Most hGM-CSF produced by transgenic tobacco cell cultures and secreted to the medium was confirmed to be rapidly degraded by protease in medium. To increase the productivity, therefore, various protein stabilizers such as gelling agents such as carrageenan and alginate, polymers, polyols, and amino acids have been tested. The stability of hGM-CSF in spent medium without cells was improved by the presence of gelling agents. However, the reason for the enhanced production by the addition of gelling agents may be due to the increased expression level and permeability rather than stability. The addition of DMSO inhibited the cell growth, but improved specific yield. The others were not effective for stability as well as hGM-CSF production.

• 전기의세계
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• v.30 no.5
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• pp.306-312
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• 1981

The Townsend discharge domain is generally observed with stable positive characteristics in N$_{2}$ gas discharge at low pressures differently in the others, which transfer immediately to glow dischage after self-sustaining discharge starts. In this paper, the presence of the stable Townsend discharge, applied voltage-discharge current characteristics and the effect of disgased electrode surface on stable townsend discharge are studied experimentaly in N$_{2}$ gas mixed with 0.05% of No in volume. As the result of this experiment, the stable Townssend discharge is observed only in pure nitrogen with the valve of pd.geq.8[torr.cm] (p=gas pressure, d=gap spacing), but not in gas mixtures. This is considered that No gas in gas mixtures disexcites effectively the metestble state of nitrogen.

• Journal of Chest Surgery
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• v.23 no.6
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• pp.1158-1167
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• 1990

Since November 1979, 20 patients have undergone excision of an intracardiac myxoma, which was located in the left atrium in 18[90%], in the right atrium in 1[5%], and in the right ventricle in 1[5%], There were 17 female and 3 male patients with a mean age of 43.5 years [range 23 to 68 years]. Only one patient was asymptomatic, the others were seen mostly exertional dyspnea, palpitation, sings of systemic illness. Diagnosis was confirmed by echocardiography in all cases and angiography in two cases, preoperatively, The myxomas were successfully removed in all patients, either by shaving them from the atrial septum or by excising a portion of normal atrial septum with tumor. All heart chambers were carefully explored for presence of multi-centric myxoma or tumor debris. We conclude that excision of intracardiac myxoma is curative and long term survival is excellent and long term clinical and echocardiographic follow-up are recommended since late recurrence, although rare, has been reported.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.539-541
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• 2023

COVID-19 is a viral pandemic disease that spreads widely all around the world. The only way to identify COVID-19 patients at an early stage is to stop the spread of the virus. Different approaches are used to diagnose, such as RT-PCR, Chest X-rays, and CT images. However, these are time-consuming and require a specialized lab. Therefore, there is a need to develop a time-efficient diagnosis method to detect COVID-19 patients. The proposed machine learning (ML) approach predicts the presence of coronavirus based on clinical symptoms. The clinical dataset is collected from the Israeli Ministry of Health. We used different ML classifiers (i.e., XGB, DT, RF, and NB) to diagnose COVID-19. Later, classifiers are optimized with the Bayesian hyperparameter optimization approach to improve the performance. The optimized RF outperformed the others and achieved an accuracy of 97.62% on the testing data that help the early diagnosis of COVID-19 patients.

• Asian Journal for Public Opinion Research
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• v.1 no.1
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• pp.26-41
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• 2013

The rise and fall of social research methods rely on how much a certain method is able to appropriately reflect the change of society. The present research proposes new mobile surveying methods, considering the current and future trends in Korea. In particular, this research focuses on environmental pressure (time constraints, the presence of others and the place) as one of the major factors influencing the effects of survey modes. For example, landline surveys are conducted in the respondent's home, which is a private and fixed space. On the other hand, surveys on mobile phones can be conducted in diverse places with other people around. After sampling 500 landline respondents and 500 mobile phone respondents using a quota method, the same questionnaire was used for both the mobile and landline interviews. The findings are generally consistent with the literature supporting the data quality and comparability of the mixed mode survey. These results are encouraging for researchers designing surveys that feature mobile phone data collection.