• Corrosion Science and Technology
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• v.16 no.2
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• pp.85-89
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• 2017

One of the most challenging issues in the oil and gas industry is corrosion assessment and management in subsea structures or equipment. At present, almost all steel pipelines are sensitive to corrosion in harsh working environments, particularly in salty water and sulphur ingress media. Nowadays, the most commonly practiced solution for a damaged steel pipe is to entirely remove the pipe, to remove only a localized damaged section and then replace it with a new one, or to cover it with a steel patch through welding, respectively. Numerous literatures have shown that fiber-reinforced polymer-based composites can be effectively used for steel pipe repairs. Considerable research has also been carried out on the repair of corroded and gouged pipes incorporated with hybrid natural fiber-reinforced composite wraps. Currently, further research in the field should focus on enhanced use of the lesser and highly explored hybrid-biocomposite material for the development in corrosion prevention. A hybrid-biocomposite material from renewable resource based derivatives is cost-effective, abundantly available, biodegradable, and an environmentally benign alternative for corrosion prevention. The aim of this article is to provide a comprehensive review and to bridge the gap by developing a new hybrid-biocomposite with superhydrophobic surfaces.

• Journal of Chest Surgery
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• v.16 no.3
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• pp.331-336
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• 1983

Cor triatriatum is a rare congenital malformation of the heart, in which a septum stretches in a transverse or oblique plane through the left atrium, thus separating it into two compartments. The upper one connects with the pulmonary veins, and the lower one connects with the left ventricle. Due to the rarity of, and great difficulty in-diagnosing, cor trlatrlatum, data On the surgery of this disease are of necessity very limited and so accurate pre-operative diagnosis was very difficult to make. `We experienced a case of the cyanotic congenital heart disease which was diagnosed as a large atrlal septal defect with streaming venous blood from inferior vena cava to left atrium through atrial septal defect in August, 1982. We found that there were transverse septum in the left atrium through atrlal septal defect, the pulmonary venous drainage were located in the upper chamber of the left atrium, and the lower chamber was connected with the left atrial appendage, mitral valve and `left ventricle. But our case had not any opening in this transverse septum and the right atrium was connected with the upper chamber of the left atrium through the upper part of the atrlal septal defect, and was communicated with the lower chamber of the left atrium through the lower part of the atrlal septal defect. We excised the transverse septum and repair this atrial septal defect with Woven Dacron patch accompanying with the drainage of coronary sinus to right atrium. The post-operative course was not eventful and he was discharged with good result on the post-operative 8th day, and has been in good .condition up to now for longer than 10 months.

• Journal of Chest Surgery
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• v.16 no.3
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• pp.289-294
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• 1983

The report is concerned to our experience of 12 cases of open heart surgery under the extracorporeal circulation at the Department of Thoracic and Cardiovascular Surgery, Chosun University Hospital during the period between Nov, 1979 and April, 1983. 1. There were 4 cases of congenital anomaly and 8 cases of acquired heart disease. 2. There were 6 male and 6 female patients with a mean age of 20 years. [range 9 to 33 years]. 3. The cases induced 2 ventricular septal defect, 2 atrial septal defects and 8 acquired valvular heart diseases. 4. The surgical managements were 2 primary repair for atrial septal defect and 2 patch closure for ventricular septal defect, 1 triple valve replacement [AVR MVR TVR], 1 aortic valve replacement, 4 double valve replacement [AVR MVR] and 2 open mitral commissurotomy for pure mitral stenosis. 5. The average cardiopulmonary bypass time was 61.5 minutes for congenital heart disease and 201.4 minutes for acquired valvular heart disease and the average aortic cross clamping time was 36.75 minutes for the former and 165.6 minutes for the latter. 6. Postoperatively, there were 1 Alopecia, 1 Electric burn and 1 wound infection as complication. 7. Overall operative mortality was 8.3%. 7. All patients received valve replacement were recommended anticoagulation with persantin.

• Journal of Chest Surgery
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• v.34 no.10
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• pp.775-780
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• 2001

We report a case of the successful anatomical correction of the Taussig-Bing anomaly associated with the interrupted aortic arch and intramural left coronary artery for an 38 day-old infant Aortic arch and neoaortic reconstructions were conducted without any prosthetic or pericardial patch. Intramural left coronary was separated from right one after partial detachment of aortic commissure and both coronary artery buttons were transferred separately to the proximal main pulmonary artery(nee-aorta). Delayed sternal closure was done 3 days after the operation and hospital discharge was delayed for a month because of postoperative pneumonia. Now he is 5 months old and free of symptoms and cardiac drugs.

• Journal of Chest Surgery
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• v.29 no.11
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• pp.1207-1211
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• 1996

During the recent 10 years, ten patients with ruptured sinus of Valsalva were operated on our institute. Eight patients were congenital but two patients were proved acquired lesions due to bacterial endocarditis. Coexistent cardiac lesions were 4 aortic regurgitations, 2 atrial septal defects, 1 ventricular septal defect, 1 tricuspid regurgitation and 1 mitral regurgitation. In all cases, aneurysms of sinus of Valsalva arose from the right coronary sinus, and they ruptured to right ventricle in 8 patients and to right atrium in 2 patients. We preferred double approach, through both the aorta and the involver. cardiac chamber, The repair of ruptured site was performed Dacron patch graft in 8 patients and simple closure in 2 patients. Operative results were very good in all cases with no surgical mortality.

• Journal of Chest Surgery
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• v.48 no.1
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• pp.63-66
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• 2015

We present a case of left ventricular pseudoaneurysm, which is a very rare and fatal complication of cardiac procedures such as mitral valve replacement. A 55-year-old woman presented to the Department of Thoracic and Cardiovascular Surgery at Hanyang University Seoul Hospital with chest pain. Ten years prior, the patient had undergone double valve replacement due to aortic regurgitation and mitral steno-insufficiency. Surgical repair was successfully performed using a prosthetic pericardial patch via a left lateral thoracotomy.

• Journal of Chest Surgery
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• v.35 no.4
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• pp.303-306
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• 2002

Patients with severe Ebstein's anomaly showing in the neonatal period, represent progressive cardiac enlargement with pulmonary hypoplasia and functional pulmonary atresia with patent ductus alteriosus-dependent pulmonary circulation. Biventricular repair in these patients had been mostly unsuccessful except for Starnes' procedure that converts the anatomy to single ventricle physiology for Fontan procedure. A 4-days old male was admitted with the diagnosis of severe Ebstein's anomaly with anatomic pulmonary atresia and severe cardiac enlargement. He successfully underwent biventricular repair with vertical plication method of atrialized right ventricle, tricupid annuloplasty, transannular right ventricular outflow tract reconstrulltion, atrial septal defect patch closure with fenestration, and right atrial reduction angioplasty Postoperatively, cardiothoracic ratio was significantly reduced and mild tricuspid regurgitation was remnant in echocardiography. The patient is currently 10 months old and is fully active without restrictions.

• Journal of Chest Surgery
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• v.33 no.10
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• pp.785-791
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• 2000

Left ventricular dysfuction is common in immediate postoperative periods after surgical correction of heart diseases with chronic left ventricular volume overload. We speculated postoperative changes of left ventricular volume and unction in patients with patent ductus osus(PDA) who had underwent surgical repair at ages older than 16 years. Factors influencing postoperative left ventricular volume and function were also analyzed. Material and Method: From August 1989 to August 1999 thirty-siz adult patients with PDA 28 females and 8 males. were enrolled in this study. Their age ranged from 16 years to 57 years(mean :32 years). Types of surgical repair were division with primary closure in 22, division with patch closure in 6, internal obliteration using cardiopulmonary bypass in 4 and ligation in 4. Aortic clamping was combined during surgical repair in 22(61%) and cardiopulmonary bypass was used in 8(22%) Two-dimensional echocardiography studies were performed in 34(94%) preoperatively and in 25(66%) immediate postoperatively to assess postoperative changes of left ventricular internal dimensions. left ventricular volume and ejection fraction. Duration of postoperative follow-up ranged from 1 month to 99 months (mean:22 months) and 10 patients underwent 16 echocardiographic evaluation during this period Result : Preoperative and postoperative left ventricular systolic dimensions(LVIDs) were 42$\pm$8.0mm and 42$\pm$8.3mm left ventricular diastolic dimensions(LVIDd) were 64$\pm$10.0mm and 56$\pm$7.4mm left ventricular end systolic volumes(LVESV) were 62$\pm$19cc (z=1.87$\pm$0.06) and 59$\pm$24cc(z=1.78$\pm$0.08) left ventricular end diastolic volumes(LVEDL) were 169$\pm$40cc(z-1.17$\pm$0.1) and 112$\pm$29cc(z=0.85$\pm$0.1) and ejection fractions(EF) were 66$\pm$6.7% and 48$\pm$12.6% respectively. There were statistically significant differences between preoperative and postoperative values in LVDIDd(p=0.001) LVEDV(p=0.001) and EF(p=0.0001) while no significant difference is LVIDs and LVESV. Postoperative depression of ejcection fraction was significantly related with z-score of preoperative LVESV and LVEDV by univariateanalysis while LVEDV only was significant risk factor for postoperative LV dysfunction by multiple regressioin analysis ($\Delta$LVEF=-13.3-4.62$\times$LVEDV(z), p=0.001) During the follow-up periods ejection fractions become normalized in all except one patients. Conclusion ; Left ventricular function is usually deteriorated after the surgical correction of PDA in adult age and preoperative LVEDV is a major determinant of postoperative LV function.

• Composites Research
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• v.31 no.1
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• pp.1-7
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• 2018

In the case of a conventional composite patch repair using a heat blanket, the adhesive is pressurized using only a vacuum bag. In this study, however, a pressurization system has been developed to apply additional air pressure on the vacuum bag. In order to verify the performance of the developed system, the composite laminates were repaired with scarf patches and then tested under tensile load to be compared with the strength of the defect-free laminate. Tensile tests were also conducted on specimens with the same configuration but bonded in an autoclave. As a result of the test, the tensile strengths of the specimens repaired using the heat blanket with vacuum only without external pressure, the specimens repaired with additional pressure by the developed system, and the specimens repaired with the same external pressure in an autoclave, showed the strength recovery ratios of 74.9, 81.0, and 78.2%, respectively. The results of the tensile test after moisture saturation and the dried fatigue test also showed that the strength recovery ratios of the specimens repaired under the external pressure of 1 atm using the developed system are slightly higher than that of specimens bonded in autoclave.

• Journal of Chest Surgery
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• v.39 no.4 s.261
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• pp.275-280
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• 2006

Background: Aortopulmonary window (APW) is a very rare congenital heart anomaly, often associated with other cardiac anomalies. It causes a significant systemic to pulmonary artery shunt, which requires early surgical correction. Accurate diagnosis and surgical correction will bring good outcomes. The purpose of this study was to describe our 20-year experience of aortopulmonary window. Material and Method: Between March 1985 and January 2005, 16 patients with APW underwent surgical repair. Mean age at operation was $157.8{\pm}245.3$ ($15.0{\sim}994.0$) days and mean weight was $4.8{\pm}2.5$ ($1.7{\sim}10.7$) kg. Patent ductus arteriosus (8), atrial septal defect (7), interruptedaortic arch (5), ventricular septal defect (4), patent foramen ovate (3), tricuspid valve regurgitation (3), mitral valve regurgitation (2), aortic valve regurgitation (1), coarctation of aorta (1), left superior vena cavae (1), and dextrocardia (1) were associated. Repair methods included 1) division of the APW with primary closure or patch closure of aorta and pulmonary artery primary closure or patch closure (11) and 2) intra-arterial patch closure (3). 3) Division of the window and descending aorta to APW anastomosis (2) in the patients with interrupted aortic arch or coarctation. Result: There was one death. The patient had 2.5 cm long severe tracheal stenosis from carina with tracheal bronchus supplying right upper lobe. The patient died at 5th post operative day due to massive tracheal bleeding. Patients with complex aortopulmonary window had longer intensive care unit and hospital stay and showed more morbidities and higher reoperation rates. 5 patients had reoperations due to left pulmonary artery stenosis (4), right pulmonary artery stenosis (2), and main pulmonary artery stenosis (1). The mean follow-up period was $6.8{\pm}5.6$ (57.0 days$\sim$16.7 years)years and all patients belonged to NYHA class 1. Conclusion: With early and prompt correction of APW, excellent surgical outcome can be expected. However, optimal surgical method needs to be established to decrease the rate of stenosis of pulmonary arteries.