• Journal of Chest Surgery
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• v.32 no.6
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• pp.504-509
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• 1999

Background: Heart transplantation is considerated for a selected certain group of complicated congenital heart disease in neonates because corrective surgery is very difficult and has high mortality. Precise planning of transplantation is necessary to adequately fit the donor heart to the recipient. Material and Method: We have performed 4 neonatal pig heart transplantations to test the technical feasibility. Experiment 1: The transplantation was performed using the same technique as the adult heart transplantation. Experiment 2: The transplantation for hypoplastic left heart syndrome was simulated as we reconstructed the whole aortic arch with donor aorta. Experiment 3: The heart transplantation was done with radical pulmonary artery reconstruction. Experiment 4: The experiment was performed for a long term survival. Result: Preoperative planning was very important for adequate fitting. All animals could be weaned from cardiopulmonary bypass, however, two animals died due to bleeding at pulmonary artery and left atrium. Conclusion: We concluded that the neonatal heart transplantation can be applied in some complicated Further using animal model is mandatory.

• Convergence Security Journal
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• v.19 no.4
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• pp.133-142
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• 2019

Although torrents and P2P sites or web hard are frequently used by users simply because they can be easily downloaded freely or at low prices, domestic torrent and P2P sites or web hard are very sensitive to copyright. Techniques have been researched and applied. Among these, title and string comparison method filtering techniques that block the number of cases such as file titles or combinations of key words are blocked by changing the title and spacing. Bypass is easy through. In order to detect and block illegal works for copyright protection, a technique for normalizing modified file titles is essential. In this paper, we compared the detection rate by searching before and after normalizing the modified file title of illegal works and normalizing the file title. Before the normalization, the detection rate was 77.72%, which was unfortunate while the detection rate was 90.23% after the normalization. In the future, it is expected that better handling of nonsense terms, such as common date and quality display, will yield better results.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.5
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• pp.100-105
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• 2010

A multi-band low noise amplifier (LNA) is designed in 90 nm RF CMOS process for 3GPP LTE (3rd Generation Partner Project Long Term Evolution) applications. The designed multi-band LNA covers the eight frequency bands between 1.85 and 2.8 GHz. A tunable input matching circuit is realized by adopting a switched capacitor array at the LNA input stage for providing optimum performances across the wide operating band. Current steering technique is adopted for the gain control in three steps. The performances of the LNA are verified through post-layout simulations (PLS). The LNA consumes 17 mA at 1.2 V supply voltage. It shows a power gain of 26 at the normal gain mode, and provides much lower gains of 0 and -6.7 in the bypass-I and -II modes, respectively. It achieves a noise figure of 1.78 dB and a IIP3 of -12.8 dBm over the entire band.

• Journal of The Korean Society of Clinical Toxicology
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• v.14 no.1
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• pp.1-8
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• 2016

Purpose: Extracorporeal life support (ECLS) is a term used to describe a number of modalities including extracorporeal membrane oxygenation (ECMO) to support cardiac and/or pulmonary systems. The purpose of this study is to review the available evidence regarding the effect of ECLS in patients with acute poisoning. Methods: Electronic literature searches with PubMed, Embase, Cochrane library, and KoreaMed were conducted for identification of relevant studies addressing ECLS in treatment of acute poisoning. The literature search was conducted by two investigators in March, 2016 with publication language restricted to English and Korean. The toxic substance, technique of ECLS, and final outcome of each case were analyzed. Results: The final analysis included 64 articles including 55 case reports. There were no articles classified according to a high level of evidence such as randomized trial and prospective cohort study. ECLS treatment was used in the management of patients poisoned with 36 unique substances. Venovenous ECMO was performed in 4 cases. Among the reported cases, 10 patients died despite treatment with ECLS. Conclusion: Evidence supporting ECLS for patients with acute poisoning is inadequate. However, many case reports suggest that early consideration of ECLS in poisoned patients with refractory cardiac arrest or hemodynamic compromise refractory to standard therapies may be beneficial.

• Journal of Chest Surgery
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• v.34 no.9
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• pp.720-723
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• 2001

A case of Marfan’s syndrome with atresia of right coronary artery is reported. A 45-year-old woman, who was diagnosed as Marfan’s syndrome 1 year ago, came to the hospital complaining of acute chest pain. The patient showed arachynodactyly, pectus carinatum, and long and slender extremities. In echocardiography there were severe aortic regurgitation measured grade IV and aortic dilatation of ascending aorta maximally 5.9 cm in diameter. Mitral regurgitation was mild, but there were also moderate left ventricular dilation and moderately decreased ejection fraction of left ventricle. At operation, atresia of right coronary artery was found. We performed Bentall type operation with SJM 27mm valved conduit for left coronary artery, and Piehler’s modification for right coronary artery bypass using 6mm PTFE graft. The atretic portion of right coronary artery from the suspected right coronary ostium to distal coronary flow was about 4 cm in length. The combination of right coronary artery atresia and Marfan’s syndrome is very rare. The author describes the rare case, which is treated with combined technique of Bentall and Piehler modification for reconstruction of coronary circulation.

• Journal of Chest Surgery
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• v.45 no.3
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• pp.148-154
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• 2012

Background: The adequate management of mild to moderate dilatation of the ascending aorta during cardiac operations remains controversial. In this study, we present the short-term outcomes of 90 patients undergoing ascending aortic wrapping with a Dacron graft during other cardiac operations. Materials and Methods: From March 2008 to January 2011, 90 consecutive patients underwent treatment for ascending aortic aneurysm using the external wrapping technique during the concomitant procedure. The study group consisted of 49 male and 41 female patients with a mean age of $58.7{\pm}13$years. The primary cardiac surgical procedures were coronary artery bypass grafting (CABG) in 3, aortic valve replacement in 2, and aortic valvuloplasty in 85 patients (isolated in 62 and combined with CABG or mitral valvuloplasty in 23). The ascending aorta diameter was measured using a computed tomography scan within 4 weeks after surgery, and was compared with the preoperative value. Results: The diameters of the ascending aorta wrapped with the Dacron graft were significantly reduced within a month after surgery from $46.4{\pm}4.3$ mm to $33.0{\pm}3.5$ mm (p<0.05). There was no early mortality or major surgical complication. During the mean follow-up period of $15.4{\pm}5.2$ months, there was only one late death caused by septic multiorgan failure. Conclusion: Dacron wrapping of the ascending aorta offers excellent results with very low mortality and morbidity, and it can be regarded as a safe and effective method for the treatment of moderately dilated ascending aorta in selected patients.

• Journal of Chest Surgery
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• v.30 no.12
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• pp.1205-1213
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• 1997

This study reviewed useful aspects of the intraoperative transesophageal echocardiography among the patients in whom heart surgery were undertaken between January 1996 and July 1996 at St.Pauls hospital, Medical College of Catholic University, Seoul, Korea. During that period, 61 patients were operated on because of valvular heart disease(25 patients), coronary artery disease(22 patients), congenital heart disease(13 patients), and combined coronary artery disease and valvular heart disease(1 patient). Two patients(1 redo-VSD and 1 valvular heart diease) needed repeated aortic cross clamping and complementary procedures because of incomplete initial procedures. There was no incidence of air embolism. We could observe significant relationship of cardiac output monitoring methods either by thermodilution technique and transesophageal echocardiography by linear regression analysis(p<0.001). We tested myocardial response(percentage of systolic wall thickness, PSWT) with low dose dobutamine challenge to predict post-CABG myocardial perfusion. And the test showed statistically significant resp.onse(sensitivity 76%, specificity 94.7%, positive predictive value 95%, negative predictive value 75%). These results suggest that cardiac surgeon could draw more benefits by intraoperative transesophageal echocardiography.

• Journal of architectural history
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• v.23 no.1
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• pp.7-19
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• 2014

This study considers the proper repair techniques by examining the most representative repair cases of the Korean arch bridges and proposes the constructional manual which can apply similar occasions. The cases are Seonamsa Seungseongyo and Songgwangsa Geukrockgyo where this researcher had taken part in the repair works. This Study proposes the maintenance construction manual about the performance degradation drew by performance degradation of the both Korean arch bridges in the maintenance process. First, arch bridge maintenance should be carried out in the dry season, when water is impermeable in the bottom surface of the bridge. Moreover, risk factors of the maintenance should be excluded to secure the water vally flow, the bypass and the temporary bridge. Second, prior to repair, it has to precede (1)3D shooting (2)formal examination (3)structure safety test (4)geological and lithic surveys (5)arch curvature establishment and makeshift frame settlement before transformation (6)relationship expert comments. Third, if the baduk and the foundation stones are inevitable to replace due to performance degradation on the foundation, it should use the high quality stones and secure greater stress by extending the standard range. The foundation on irregular rock needs to be flattened and underside on the replaced materials require Grengyijil to deliver the equal loads. Fourth, In the process of dismantling the stones of the arched bridge, it could make heavy weathering degree and not reuse the materials. Charge should converge the expert advices to choose the reuseable, the conservate and the alternative materials, and increase the reutilization of the raw materials by preservation and reinforcement treatments. Fifth, the side wall should be repaired by the rubble work technique which is not able to pile compost satiety, so it must use long depth of masonary stones for reinforcement. It is considered to reinforce the stone wall in shore as much as possible and protect the abutment and the side wall on the upstream for the arch bridge maintenance works.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.3
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• pp.535-545
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• 2014

As the software industry has developed, the attacks making use of software vulnerability has become a big issue in society. In particular, because the attacks using the vulnerability of web browsers bypass Windows protection mechanism, web browsers can readily be attacked. To protect web browsers against security threat, research on fuzzing has constantly been conducted. However, most existing web browser fuzzing tools use a simple fuzzing technique which randomly mutates DOM tree. Therefore, this paper analyzed existing web browser fuzzing tools and the patterns of their already-known vulnerability to propose an event and command based fuzzing tool which can detect the latest web browser vulnerability more effectively. Three kinds of existing fuzzing tools were compared with the proposed tool. As a result, it was found that the event and command based fuzzing tool proposed was more effective.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.6
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• pp.463-472
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• 2020

Direct reprogramming, also known as a trans-differentiation, is a technique to allow mature cells to be converted into other types of cells without inducing a pluripotent stage. It has been suggested as a major strategy to acquire the desired type of cells in cell-based therapies to repair damaged tissues. Studies related to switching the fate of cells through epigenetic modification have been progressing and they can bypass safety issues raised by the virus-based transfection methods. In this study, a protocol was established to directly convert fully differentiated fibroblasts into diverse mesenchymal-lineage cells, such as osteoblasts, adipocytes, chondrocytes, and ectodermal cells, including neurons, by means of DNA demethylation, immediately followed by culturing in various differentiating media. First, 24 h exposure of 5-azacytidine (5-aza-CN), a well-characterized DNA methyl transferase inhibitor, to NIH-3T3 murine fibroblast cells induced the expression of stem-cell markers, that is, increasing cell plasticity. Next, 5-aza-CN treated fibroblasts were cultured in osteogenic, adipogenic, chondrogenic, and neurogenic media with or without bone morphogenetic protein 2 for a designated period. Differentiation of each desired type of cell was verified by quantitative reverse transcriptase-polymerase chain reaction/western blot assays for appropriate marker expression and by various staining methods, such as alkaline phosphatase/alizarin red S/oil red O/alcian blue. These proposed procedures allowed easier acquisition of the desired cells without any transgenic modification, using direct reprogramming technology, and thus may help make it more available in the clinical fields of regenerative medicine.