• Journal of Welding and Joining
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• v.32 no.6
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• pp.8-13
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• 2014

One of the main challenges of the automatic arc welding process which has been widely used in various constructions such as steel structures, bridges, autos, motorcycles, construction machinery, ships, offshore structures, pressure vessels, and pipelines is to create specific welding knowledge and techniques with high quality and productivity of the production-based industry. Commercially available automated arc welding systems use simple control techniques that focus on linear system models with a small subset of the larger set of welding parameters, thereby limiting the number of applications that can be automated. However, the correlations of welding parameters and bead geometry as welding quality have mostly been linked by a trial and error method to adjust the welding parameters. In addition, the systematic correlation between these parameters have not been identified yet. To solve such problems, a new or modified models to determine the welding parameters for tandem GMA (Gas Metal Arc) welding process is required. In this study, A new predictive model called STACO model, has been proposed. Based on the experimental results, STACO model was developed with the help of a standard statistical package program, MINITAB software and MATLAB software. Cross-comparative analysis has been applied to verify the reliability of the developed model.

• Applied Microscopy
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• v.24 no.1
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• pp.11-27
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• 1994

The morphological development of the carotid body was studied by electron microscope in human fetuses from 40mm to 260mm crown rump length (10-30 weeks of gestational age). At 40mm fetus, the carotid body was composed of cluster of primitive glomus cells, primitive supporting cells, unmyelinated nerve fibers, and blood capillaries. In connective tissue between internal and external carotid arteries adjacent to the superior cervical sympathetic ganglion, two types of glomus cells through all prenatal period were found. Dark cells contained a dense cytoplasm with conspicuous large dense-cored granules, whereas light cells had a less dense cytoplasm with dense-cored granules. The light cells contained dense-cored granules that were smaller and less abundant than those in the dark cells. The primitive supporting cells appeared star-shaped with attenuated cytoplasmic extensions intervening between the adjacent glomus cells. Synaptic contact between the axon terminals and soma of the glomus cells were first observed at 40mm fetus. In 80-100mm fetus, the carotid body contained tightly packed collection of glomus cells and supporting cells which surrounded the abundant thin-walled blood vessels. Intercellular junctions between the glomus cells and adjacent cells were commonly seen. Nerve endings on the glomus cells have the form of small boutons and the other from of large calyces. During the second half of the fetal period, the glomus cells were completely enveloped by supporting cells and nerve terminals. At 260mm, the morphological features of carotid body were similar to those of human adult. The result of this study demonstrates that there are differences between the carotid body and aorticopulmonary bodies, especially with respect to their synaptic complexes, abundant blood capillaries, and two glomus cell types.

• Journal of fish pathology
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• v.24 no.3
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• pp.213-223
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• 2011

Among wild marbled sole, Pleuronectes yokohamae caught in west coastal area, Chungnam, tumor-bearing fish were found. Parasites and pathogenic bacteria were not detected and CPE was not observed. Using the light microscope, the epidermal layer of wild P. yokohamae was significantly thickened compared to the normal skin. The lesion was formed papillary folds. Hypertropical epithelial cells revealed karyolysis, marked nucleolus and cloud swelled cytoplasm. In the epidermal layer of the lesion, X-cell that is characterized by oval and small pale nucleus and prominent nucleolus was observed. Dermal layer had newly formed vessels. The size of mucous cell in the papilloma lesion was significantly increased compared to the normal. In this study, no pathogens were found, so future works for finding cause of the papilloma in the P. yokohamae are needed.

• Journal of Pharmacopuncture
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• v.8 no.3
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• pp.5-9
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• 2005

Observation of intra-vascular threadlike structures in the blood vessels of rats is reported with the images by differential interference contrast microscope, and fluorescence inverted microscope of the acridine-orange stained samples. The confocal microscope image and the hematoxylin-eosin staining revealed the distinctive pattern of nuclei distribution that clearly discerned the threadlike structure from fibrin, capillary, small venule, arteriole, or lymph vessel. Physiological function of the intra-vascular thread in connection with acupuncture is discussed. Especially, this threadlike duct can be a circulation path for herb-liquid flow, which may provide the scientific mechanism for therapeutic effect of herbal acupuncture.

• Archives of Plastic Surgery
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• v.34 no.6
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• pp.759-764
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• 2007

Purpose: Various types of flaps, with their own advantages and disadvantages, have been described for reconstruction of soft tissue defect with exposure of tendons, bones, or joints in the hand or foot. Local flaps with random vascularity have a limitation by their length. Free flaps are time-consuming procedure that may require the sacrifice of some major vessels. The ideal flap for covering soft tissue defects of the hand or foot must provide subcutaneous tissue that tendons can glide through which, supply enough subcutaneous tissue for cover of vital neural, bony, vascular and joint structures, and it has to be aesthetically pleasing. The adipofascial flap fulfills these criteria. It allows immediate or early closure of difficult wound of hand and foot in an easy way, and is especially indicated for small to medium-sized defects. Methods: From October 2005 to December 2006, seven cases underwent this procedure to reconstruct soft tissue defect on hand or foot. Results: All flaps survived completely, and no complications were observed. Conclusion: The adipofascial flap is a convenient flap for coverage of soft tissue with exposure of vital structure in the hand or foot, and provide several advantages, as following; easy and safe, short operating time, one stage procedure, thinness and good pliability of the flap, preservation of the major vascular pedicles, skin preservation at the donor site, thus preserve the shape of the limb and minimize donor site scar.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.702-708
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• 2014

Background Lower abdominal soft tissue transfer is the standard procedure for breast reconstruction. However, abdominal wall weakness and herniation commonly occur postoperatively at the donor site. To reduce the morbidities of the donor site, the superficial inferior epigastric artery (SIEA) flap was introduced, but inconsistent anatomy of the SIEA has reduced its utility. In the present study, the anatomy of the superficial inferior epigastric vessels in Korean women was determined with regards to breast reconstructive surgery. Methods The vascular anatomies of the SIEA and superficial inferior epigastric vein (SIEV) were evaluated on 32 breast cancer patients receiving free transverse rectus abdominis musculocutaneous flap reconstruction after mastectomy. The existence, pulsation, location, external diameter, and depth of the SIEA and SIEV were measured at the lower abdominal incision level. Results SIEA and SIEV were present in 48/64 (75.00%) and 63/64 (98.44%) hemi-abdomens, respectively. Pulsation of the SIEA was found in 44/48 (91.67%) cases. The mean locations of SIEA and SIEV were +5.79 (${\pm}12.87$) mm, and -8.14 (${\pm}15.24$) mm from the midpoint between the anterior superior iliac spine and symphysis pubis, respectively. The mean external diameters of SIEA and SIEV were 1.20 (${\pm}0.39$) mm and 1.37 (${\pm}0.33$) mm, and they were found at a mean depth of 9.75 (${\pm}2.67$) mm and 8.33 (${\pm}2.65$) mm, respectively. Conclusions The SIEA was absent in 25% of Korean women and had a relatively small caliber. Therefore, careful preoperative assessment of the lower abdominal vasculature is required to achieve successful breast reconstruction using SIEA flaps.

• Archives of Reconstructive Microsurgery
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• v.2 no.1
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• pp.82-92
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• 1993

A comparative study was undertaken to evaluate the contact Neo-dymium : yttrium aluminum garnet(Nd:YAG) laser system for vascular anastomosis of small caliber blood vessels(diameter 0.5-1.2 mm) in the animal model. In this study 40 femoral arteries and 40 femoral veins of Sprague-Dawley rats were anastomosed by contact laser assisted microvascular anastomosis(LAMA) utilizing 3 stay sutures which were placed 120 degrees apart and the intervals welded with contact Nd:YAG laser unit, conventionally sutured anastomosis(CSA) served as controls. The time needed for vascular anastomosis, patency rate(immediate postoperative, postoperative 2nd day, postoperative 1 week, postoperative 4 weeks), gross and microscopic evaluations were compared to conventional microsurgical suture technique. The results are as follows: 1. Postoperative patency rate was 82.5% for femoral artery and 75% for femoral vein by contact LAMA technique compared to 90% and 75% by CSA technique at postoperative 4 weeks. 2. Less time-consumed for arterial anastomosis by 6 minutes 23 seconds and venous anastomosis by 8 minutes 55 seconds with contact LAMA technique compared to CSA technique. 3. Grossly almost complete healing had taken place by postoperative 1 week by contact LAMA technique. 4. Aneurysm formation was 5% for femoral artery and 15% for femoral vein by contact LAMA technique compared to 5% and 10% respectively by CSA technique. 5. Microscopically, re-endothelization was complete by postoperative 7th day by contact LAMA technique. There was less medial hypertrophy and hyperplasia and also less inflammatory response compared to CSA.

• Archives of Reconstructive Microsurgery
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• v.5 no.1
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• pp.80-91
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• 1996

A free rectus abdominis flap can include a variable amount of muscle length depending on recipient site requirements. There is also great flexibility in flap design in terms of size, orientation of its axis, and the level of its location over the muscle. It is safe to design the skin island across the midline. Though skin islands designed over the most inferior portion of the abdomen have not always proved reliable when based on the superior epigastric artery, free flaps based on the inferior pedicle can be successfully designed in this area. As free flap based on the inferior epigastric vessels, this flap has been useful for large head and neck defects following ablative procedures, for facial contour restoration as a buried flap, for upper extremity defects, for lower extremity defects such as coverage of grade III tibial fractures and for breast reconstruction. A free rectus abdominis muscle or myocutaneus flap was used in 8 patients. The operations were performed between Sep. of 1994 and April of 1996. The patients were tongue cancer 1 case, chronic facial palsy 1 case, unilateral breast reconstruction 1 case, upper and lower extremity injury 5 cases. The free rectus abdominis muscle flaps were 4 cases and the free myocutaneous flaps were 4 cases. There was no failure of the flap, except one partial necrosis. One case of the skin grafts on the muscle flap was regrafted. One case of reoperation due to venous thrombosis was performed. In tongue cancer patient, a orocutaneous fistula was occurred, but conservative treatment and secondandry skin graft were done. In conclusion, a free rectus abdominis flap has many advantages such as a long and constant pedicle, easy dissection, enough soft tissue available, scar on the donor site to be hiddened, no need for changing position. So we think that this flap is the most useful one for small or moderate sized defects on the various sites.

• Journal of Korean Neurosurgical Society
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• v.29 no.8
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• pp.1113-1120
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• 2000

Objectives : Despite advance in the surgical treatment of the intracranial aneurysm, we have to be surgical complication. The aim of this report is to evaluate the complication and its management in intracranial aneurysm operation. Methods : We reviewed our exprience with interesting cases of surgical complication of intracranial aneurysm : 1) rebleeding, 2) intra-operative premature rupture, 3) missed aneurysm in angiography, 4) vasospasm. Results : The risk of rebleeding was not related to the patients' initial comdition, but all other intracranial complications occurred significantly more often in patients graded poor compared with patients in good clinical condition. Rebleeding before early surgery remains as major cause of unfavorable outcome. The causes of intraoperative premature ruptures were as follows : 1) dural opening and arachnoid opening(8.3%), 2) hematoma removal(12.5%), 3) brain retraction(16.7%) 4) aneurysm dissection(62.5%). The double suction technique and primary hemostasis using a small piece of cotton or temporary clip resulted in good outcome even in cases with premature rupture. The incidence of missed aneurysm in angiography occurred in 10%. The causes were as thrombosed aneurysm, vasospasm on feeder artery. The most common missed aneurysm is also the most common aneurysm(anterior communicating artery aneurysm). The repeated angiography were documented in missed aneurysm. Balloon angioplasty is superior topapaverine for treatment of proximal vessel vasospasm by viture of a more sustained effect on the vessel. Papaverine can be useful as an adjunct to ballon angioplasty and also for the treatment of distal vessels that are not accessible for ballon angioplasty. Conclusion : The minimization of the complications and active treatment can reduced the mortality and morbidity of ruptured aneurysm patients.

• Archives of Plastic Surgery
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• v.45 no.5
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• pp.466-469
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• 2018

The highly contoured nature of the nose and the abundant free margin makes it especially difficult to reconstruct. In this report, we describe the use of a new helical rim free flap technique for the reconstruction of full-thickness nasal alar defects via supermicrosurgery. Briefly, after a wide excision with a margin of 0.7 cm, an alar defect with a size of $1{\times}1{\times}0.5cm$ was obtained, which included the full thickness of the skin, mucosa, and lower lateral cartilage. Vessel dissection was performed in a straightforward manner, starting from the incision margin for flap harvest, without any further dissection for reach the greater trunk of the superficial temporal artery. The flap was inset in order to match the contour of the contralateral ala. We closed the donor site via rotation and advancement. No donor site morbidity was observed, despite the presence of a small scar that could easily be covered with hair. The alar contour was satisfactory, and the patient was satisfied with the results. The supermicrosurgical technique did not require further dissection to identify the vessels for anastomosis, leading to better cosmetic outcomes and a reduced operating time.