• Journal of the Korean Chemical Society
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• v.27 no.3
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• pp.183-188
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• 1983

The catalytic oxidation of $SO_2$ has been investigated in the presence of vacuum-activated 10 mol % Ni-doped ${\alpha}-Fe_2O_3$ under various partial pressures of $SO_2\;and\;O_2$ at temperatures from 320 to $440{\circ}C$. Over the temperature range $320{\sim}440{\circ}C$, the activation energy is 13.8 $kcal{\cdot}mol^{-1}$. The oxidation rates have been correlated with 1.5 order kinetics; first order with respect to $SO_2$ and 0.5 order with respect to $O_2$. From the kinetic data and conductivity measurements, the adsorption, oxidation mechanism of $SO_2$ and the defect structure of vacuum-activated 10 mol % Ni-doped {\alpha}-Fe_2O_3$ are suggested. $O_2\;and\;SO_2$ appear to be adsorbed essentially as ionic species. Two surface sites, probably an $O^{2-}$ lattice and an oxygen vacancy which is induced by Ni-doping, might be required to adsorb $SO_2\;and\;O_2$. The conductivity measurements and kinetic data indicate that the adsorption process of $SO_2\;{(SO_2+O^{2-}}_{(latt)}{\rightleftharpoons}{{SO_3}^-}_{(ads)}+e')$ is the rate-determining step.

• Korean Journal of Crystallography
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• v.4 no.2
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• pp.74-85
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• 1993

Single crystals of LiNbO3 have found extensive application in electro-optic and nonlinear optic devices. However, laser-induced refartive index inhomogeneities, which have been labeled opical damage impose limits on device optical damage in LiNbO3 is imporved if more than 4.5 rml% MgO is added to the melt The laser damage thrueshold increased as much as 100 times better then that of undoped crystals. The MgO doped cystal has thus been urterlsiv81y studied since then. In the study, Mgo:LiNbOs(MLA) single crystals dopsd with 0, 2.5, 5.0, 7.5, 10.0 mol% MgO have been grown by the czocrualski technique. The metls were prepared in the platinum crluible and 15∼20mm diameter crystals were grown with a length of 20∼30mm in a resitance heater. The growth rate was 2.5mm/hr, the rotation speed 15rpn. Before sawing MLN single crystals were annealed for 24 hours under atmosphere at a temperature of 1080℃. After sawing, we have found an annual ring cross section of MNA crystals only in the direction of perpendicilar to the c-axis. Nonuniform dispusion of MgO was pointed out that the cuties of the state of oxide were strongly affected by oxygen partial pressure in.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.13-18
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• 1990

A DNA sequence encoding the adr subtype preS2 region of hepatitis B virus envelope protein was fused to 5' end of lacZ gene yielding a plasmid pTSZ, in order to produce a preS2-$\beta$-galactosidase fusion protein. Serial deletions from 3' and 5' end of preS2 were constructed in plasmids, which were expressed and their antigenicities were examined with the monoclonal antibody H8. Deletions from amino and carboxy terminal to certain points did not affect the antigenicity, but the longer deletions destroyed the antigenicity. End points of deleted preS2 sequence were determined by DNA sequencing. As a result, each end of preS2 epitope was located in the region of amino acid residue 130-132 and 140-142, respectively. Residue 143 may be supplementary for antigenic epitope since the deletion from carboxy terminal to residue 143 revealed partial defect of antigenicity. In the interval of antigenic epitope the amino acid differences between adr and adw2 subtype occurred ar residue 130, 132, and 141. This result indicated that one or more of the three residues are responsible for the binding specificity of monoclonal antibody H8 to adr subtype preS2 fusion protein.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.627-635
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• 2011

Purpose: Advanced breast cancer traditionally has been perceived as a contraindication to immediate breast reconstruction, because of concerns regarding adjuvant treatment delays and the cosmetic effects of radiotherapy to breast reconstruction, so delayed reconstruction is usually preferred in advanced breast cancer patients undergoing mastectomy. However, with the improved outcome using multimodality therapy, consisting of perioperative chemotherapy and radiotherapy, immediate breast reconstruction is now being performed as surgical option for selected advanced breast cancer patients. Additionally, advanced breast cancer patients may be needed soft tissue coverage of an extensive skin and soft tussue defect after mastectomy. Current authors have experienced several types of immediate breast and chest wall reconstruction for advanced breast cancer. Methods: From December of 2007 to June of 2009, 14 women performed for immediate breast and chest wall reconstruction for advanced breast cancer. They had been treated with neoadjuvant chemotherapy or chemoradiotherapy followed by modified radical mastectomy or radical mastectomy. Four different techniques were used immediate breast and chest wall reconstruction, which are pedicled TRAM flap (4 cases), extended LD flap with STSG (3 cases), thoracoabdominal flap (4 cases) and thoracoepigastric flap (3 cases). Results: The mean age was 53 years and mean follow up period was 9 months. Patients' oncologic status ranged stage IIIa to stage IV. Two patients had major complications: partial flap necrosis of TRAM flap and one distal necrosis of thoracoabdominal flap. Three patients with stage IV disease died from metastases. Conclusion: The result of this study suggests that immediate breast and chest wall reconstruction can be considered as surgical option for advanced breast cancer. But we need long term follow up and large prospective studies for recurrence and survival.

• Archives of Plastic Surgery
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• v.37 no.4
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• pp.396-399
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• 2010

Purpose: In hand injury, pedicle is usually damaged by avulsion injury or crushing injury. Because of postoperative pedicle obliteration, it is often hard to save the injured hand and fingers, even after successful replantation. The author introduces three cases of extensive hand injury, and successful results after applicatoin of multiple venous grafts to these patients. Methods: In all cases there was no circulation in any finger. In the first case, some vessels were extracted, so venous graft was applied to two sites of severely damaged venous sites. In the second case, venous grafts were applied to all four digital arteries of all fingers except thumb which got severely crushed, and two sites of dorsal veins. In the third case, venous graft was applied to all four digital arteries of all five fingers, and two sites of dorsal veins and palmar veins each. Results: In all cases, survival of hands and fingers was successful. In the second case, however, amputation in thumb and little finger at DIP joint level was inevitable, because of its severe damage, and the large dorsal defect on index finger was filled with DIEP free flap. Thumb was reconstructed with toe-to-thumb free flap, and additional debulking procedures and contracture release is furtherly needed. In the first case, additional surgery was done, as FDP tendon got re-ruptured, but in long term follow-up, satisfactory range of motion was attained. In the third case, FTSG on dorsal skin region was planned. as flap on dorsal area got partial necrosis. Conclusion: In hand injury, there are many structures to be repaired, but sometimes venous graft is avoided for its long operating time. Even though the length of damaged vessel is enough for anastomosis, the endothelium is often damaged (zone of injury). In extensive hand injury, successful reconstruction would be possible with active venous graft to all vessels suspicious for damage.

• Journal of Chest Surgery
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• v.3 no.2
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• pp.73-90
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• 1970

Clinical perfusion data on 16 cases of cardiopulmonary bypass using Sigmamotor pump and RyggKyvsgaard Oxygenator which performed at Seoul National University Hospital during the period of Aug. 1968 to Aug. 1970 was analized. AIl cases were hemodiluted and the perfusion was carried out under the normothermic condition. The age of the patients ranged between 6 and 43 years. The b:dy weight varied between 18.3 and 54.0 kg and the body surface area between 0.78 and 1. 59$M^2$. The priming solution was consiste:I with fresh ACD blood. Hartmann solution and Mannitol. The average amount of priming was approximately 2242 ml. The average hemodilution rate was 17%. The flow rate ranged from 1.7L to 3.5L/Min/$M^2$ and averaged 2.4L/Min/$M^2$ or 78mI/Min/kg. The duration of perfusion varied from 22 to 110 min with average of 56.9 minutes. Some hemodynamic responses were observed. The arterial pressure dropped immediately after the initiation of partial perfusion and was more marked after the total perfusion foIlowed by gradual increase to the safety level. The central venous pressure reflected the reduced blood volume especially in the cases of prolonged perfusion which lasted over 60 min. In most of the cases, red blood cell count decreased and white blood ceIl count increased after the perfusion. Hemoglobin level was decreased, averaging of 12.5mg%, Hct 3.3% and platelets count of 18% postoperatively. Plasma hemoglobin increased mildly, from pre-perfusion average value of 4. 06mg% to postperfusion value of 22.5mg%. Serum potassium was 4.4mEq/L pre-operatively and was decreased to 3.7mEq/L postoperatively. Five cases showed definite hypopotassemia immediately after the operation. Sodium and chloride decreased mildly. These electrolyte changes are thought to be related with hemodilution. diuretics and reduced blood volume during and after the perfusion. Arterial blood pH value revealed minimal to moderate elevation from preperfusion average value of 7.376 to 7.461 during perfusion and then 7.365 after perfusion. The pC02 and hicarbonate showed minimal to moderately lowered values. The total CO2 was decreased. Buffer base decreased during perfusion (Av. 42.6mEq/L) and further decreased after the perfusion (Av. 40.8mEq/L). These arterial blood acid base changes suggested that the metabolic acidosis was accompanied by respiratory alkalosis during and immediately after the perfusion. Authors belived that the acidosis could more effectively be corrected with the more additional dose of bicarbonate than we used by this study. The chest tune drainage during the first 24 hours following operation was 1158 ml in average. One case (Case No. 15) showd definite bleeding tendency and it was believed that the cause might be due to the defect of heparin and protamine titration. The average urinary out put during 24 hours post-perfusion was 1291ml. One case (Case No. ]) showed definite post perfusion oliguria. As conclusion hemodilution using fresh ACD blood. Hartmann and Mannitol solution added with Bivon and high flow rate unler normothermia. was thought to amelioratc the severity of mctabolic acidosis during and after perfusion with relatively satisfactory effect on the diuresis and bleeding tendency.

• Journal of Chest Surgery
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• v.55 no.3
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• pp.206-213
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• 2022

Background: Surgical repair of partial anomalous pulmonary venous return (PAPVR) to the superior vena cava (SVC) using the Warden procedure has favorable outcomes. However, there remain some concerns after the Warden procedure, such as sinoatrial nodal dysfunction and systemic or pulmonary venous stenosis. We investigated the outcomes of the Warden procedure for repair of PAPVR to the SVC. Methods: This retrospective study included 22 consecutive patients who underwent the Warden procedure for PAPVR between 2002 and 2018. The median age and body weight at operation were 27.5 months (interquartile range [IQR], 5.0-56.8 months) and 13.2 kg (IQR, 6.5-16.0 kg), respectively. The median follow-up duration was 6.2 years (IQR, 3.5-11.6 years). Results: There were no cases of early or late mortality. No patients had postoperative heart rhythm problems, except 1 patient who showed transient sinoatrial nodal dysfunction in the immediate postoperative period. Procedure-related complications requiring reintervention occurred in 5 patients, including 3 of 4 SVC stenosis cases and 2 pulmonary venous stenosis cases during follow-up. The rate of freedom from reintervention related to the Warden procedure was 75.9% at 10 years. Conclusion: In cases requiring extension or creation of an atrial septal defect to achieve a sufficient venous pathway, or interposition of an entire circumferential conduit between the SVC and right atrium due to the shortness of the SVC in the Warden procedure, stenotic complications of the venous pathway occurred. Careful observation of changes in the pressure gradient or anatomical stenosis is required in such patients.

• Korean Journal of Cleft Lip And Palate
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• v.3 no.1
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• pp.23-31
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• 2000

Objective: When an alveolar cleft is too large to close with adjacent mucobuccal flaps or large secondary fistula following a primary bilateral palatoplasty exists, a one-stage procedure for bone grafting becomes challenging. In such a case, we used the tongue flap to repair the fistula and cleft alveolus in the first stage, and bone grafting to the cleft defect was performed in the second stage several months later. The purpose of this paper is to report our experiences with the use of an anteriorly-based Y-shaped tongue flap to fit the palatal and labial alveolar defects and the ultimate result of the bone graft. Patients: A series of 14 patients underwent surgery of this type from January 1994 to December 1998.The average age of the patients was 15.8 years old (range: 5 to 28 years old). The mean period of follow-up following the 2nd stage bone raft operation was 45.9 months (range: 9 to 68 months). In nine of the 14 cases, the long-fork type of a Yshaped tongue flap was used for extended coverage of the labial side alveolar defects with the palatal fistula in the remaining cases the short-forked design was used. Results: All cases demonstrated a good clinical result after the initial repair of cleft alveolus and palatal fistula. There was no fistula recurrence, although Partial necrosis of distal margin in long-forked tongue flap was occurred in one case. Furthermore, the bone graft, which was performed an average of 8 months after the tongue flap repair, was always successful. Occasionally, the transferred tongue tissue was bulging and interfering with the hygienic care of nearby teeth; however, these problems were able to be solved with proper contour-pasty performed afterwards. No donor site complications such as sensory disturbance, change in taste, limitations in tongue movement, normal speech impairments or tongue disfigurement were encountered. Conclusion: This two-stage reconstruction of a bilateral cleft alveolus using a Y-shaped tongue flap and iliac bone graft was very successful. It may be indicated for a bilateral cleft alveolus patient where the direct closure of the cleft defect with adjacent tissue or the buccal flap is not easy due to scarred fibrotic mucosa and/or accompanied residual palatal fistula.

• Journal of Chest Surgery
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• v.32 no.4
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• pp.368-372
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• 1999

Background: Although there have been few reports about minimal skin incision for the repair of congenital heart lesions, minimizing an unsightly scar is a particularly important factor in growing children. We have adopted a technique that permits standard full sternotomy, conventional open chest cardiopulmonary bypass, aortic cross-clamping, left atrial vent, and antegrade cardioplegia with minimal surgical scar. Material and Method: With minimal skin incision and full sternotomy, 40 patients with congenital heart disease underwent open heart surgery from April 1997 through September 1997. Defects repaired included 30 ventricular septal defects, 4 atrial septal defects, and 1 sinus Valsalva aneurysm in 35 children(M:F=17: 18), and 3 Atrial septal defects, 1 ventricular septal defect, and 1 partial atrioventricular septal defect in 5 adults(M:F=1:4). Midline skin incision was performed from the second intercostal space to 1 or 2 cm above the xiphoid process. For full sternotomy, we used the ordinary sternal saw in sternal body, and a special saw in manubrium under the skin flap. During sternal retraction, surgical field was obtained by using two retractors in a crossed direction. Result: The proportion of the skin incision length to the sternal length was 63.1${\pm}$3.9%(5.2∼11cm, mean 7.3cm) in children, and 55.0${\pm}$3.5%(10∼13.5cm, mean 12cm) in adults. In every case, the aortic and venous cannulations could be done through the sternal incision without additional femoral cannulation. There was no hospital death, wound infection, skin necrosis, hematoma formation, or bleeding complication. Conclusion: We conclude that minimal skin incision with full sternotomy can be a safe and effective alternative method for the repair of congenital heart diseases in children and adults.

• Journal of the Korean Orthopaedic Association
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• v.55 no.3
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• pp.253-260
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• 2020

Purpose: Soft tissue defects of the distal lower extremity are commonly accompanied by a fracture of the lower extremities. Theses defects are caused by the injury itself or by complications associated with surgical treatment of the fracture, which poses challenging problem. The reverse superficial sural artery flap (RSSAF) is a popular option for these difficult wounds. This paper reviews these cases and reports the clinical results. Materials and Methods: Between August 2003 and April 2018, patients who were treated with RSSAF for soft tissue defects of the lower third of the leg and ankle related to a fracture were reviewed. A total of 16 patients were involved and the mean follow-up period was 18 months. Eight cases (50.0%) of the defects were due to an open fracture, whereas the other eight cases (50.0%) were postoperative complication after closed fracture. The largest flap measured 10×15 cm² and the mean size of the donor sites was 51.9 cm². The flap survival and postoperative complications were evaluated. Results: All flaps survived without complete necrosis or failure. One case with partial necrosis of the flap was encountered, but the wound healed after debridement and repair. One case had a hematoma with a pseudoaneurysmal rupture of the distal tibial artery. On the other hand, the flap was intact and the wound healed after arterial ligation and flap advancement. A debulking operation was performed on three cases for cosmetic reasons and implant removal through the flap was performed in three cases. No flap necrosis was encountered after these additional operations. Conclusion: RSSAF is a relatively simple and safe procedure for reconstructing soft tissue defects following a fracture of the lower extremity that does not require microsurgical anastomosis. This can be a useful treatment option for soft tissue defects on the distal leg, ankle, and foot.