• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.8
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• pp.21-29
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• 2002

In the present study, a passive control method, using a porous wall and cavity system, is applied to the shock wave/boundary layer interactions in transonic moist air flow. The two-dimensional, unsteady, compressible, Navier-Stokes equations, which are fully coupled with a droplet growth equation, are solved by the third-order MUSCL type TVD finite difference scheme. Baldwin-Lomax model is employed to close the governing equations. In order to investigate the effectiveness of the present control method, the total pressure loss of the flow and the time-dependent behaviour of shock motions are analyzed in detail. The computed results show that the present passive control method considerably reduces the total pressure losses due to the shock wave/boundary layer interaction in transonic moist air flow and suppresses the unsteady shock wave motions over the airfoil as well. It is also found that the location of the porous ventilation significantly affects the control effectiveness.

• Journal of Chest Surgery
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• v.41 no.6
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• pp.803-806
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• 2008

The Nuss procedure has good cosmetic effects, but it could be cause of bleeding and organ injury during dissection of the anterior mediastinum. We have made an effort to overcome the defects of the traditional method through the anterior mediastinum, thus we developed a transilluminated introducer that made it safer and simpler to operate within a 1cm incision only. A total of 67 patients underwent the Nuss procedure using the transilluminated introducer. Thirty-six patients underwent the procedure with the transilluminated introducer only (age<4 years). Thirty-one patients had an additional thoracoscopy ($age{\geq}14\;years$). There were no major complications, such as massive bleeding or organ injury in the thoracic cavity during or after the Nuss procedure. Our findings demonstrated that the anterior mediastium could be dissected simply and safely by the use of a transilluminated introducer during the Nuss procedure without fatal major complications, such as bleeding and organ injury.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.5
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• pp.367-375
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• 2012

Midfacial reconstruction following resection of extensive malignant oral cavity tumors constitutes a challenging problems for reconstructive surgeons. Rectus abdominis muscle free flap (RAMFF) can be considered as the optimal reconstructive option in this case, because this flap has some advantages including consistent deep inferior epigastric artery anatomy, easy to dissect with well defined skin boundaries, acceptable donor site morbidity and the ability to perform simultaneous flap harvest with oral cancer ablation surgery. The rectus abdominis muscle forms an important part of the anterior abdominal wall and flexes the vertebral column, which is a long strap-like muscle divided transversely by three tendinous intersections, fibrous bands which are adherent to the anterior rectus sheath, which is thickly enclosed by the rectus sheath, except for the posterior part below the arcuate line that is usually located midway between the umbilicus and symphysis pubis. Below the arcuate line, this muscle lies in direct contact with the transversalis fascia and parietal peritoneum. For the better understanding of RAMFF as a routine reconstructive procedure in oral and maxillofacial surgery, the constant anatomical findings muse be learned and memorized by the young doctors in the course of the special curriculum periods for the Korean national board of oral and maxillofacial surgery. This review article will discuss the anatomical basis of RAMFF with Korean language.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.3
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• pp.246-250
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• 2010

Mediastinal emphysema, also referred to as pneumomediastinum or Hamman's syndrome, is defined as the presence of air or gas within the fascial planes of the mediastinum. Superior extension of air into the cervicofacial subcutaneous space via communications between the mediastinum and cervical fascial planes or spaces occurs occasionally. The mediastinal air may originate from the respiratory tract, the intrathoracic airway, the lung parenchyma, or the gastrointestinal tract. The presence of air in the mediastinum may be spontaneous, iatrogenic or due to penetrating trauma. Pneumothorax is defined as the presence of air or gas within the pleural cavity. A pneumothorax can occur spontaneously. It can also occur as the result of a disease or injury to the lung or due to a puncture to the chest wall. Pneumomediastinum and pneumothorax is a rare complication of head and neck surgery. Nevertheless, when it occurs, it is usually considered to result from direct dissection by the air at the time of injury or of surgery. Most of the cases of pneumomediastinum and pneumothorax that have been described in the oral and maxillofacial surgery literature result from air dissecting down the fascial planes of the neck. The authors report a case with subcutaneous emphysema, pneumomediastinum and pneumothorax after orthognathic surgery.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.113-116
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• 2011

Purpose: Many fingertip injuries are associated with nail injury and it is hard to repair to original shape due to its unique characteristic. Mucosal graft is used for a defect of the nail bed injury. Hereby, we introduce a DAP flap and buccal mucosal graft, with which we could reduce the defect size of the injured fingertip and donor site morbidity at the same time, without any need for harvesting additional skin from other part of hand. Also, mucosal graft makes good cosmetic and functional outcome of nail. Methods: This method was performed in a 56-year-old man with fingertip injury on dorsal side of left thumb due to electrical saw. First, DAP flap was performed on the injured finger to reduce the size of the defect of fingertip and cover the bone exposure. Second, nail bed part of the DAP flap was de-epithelized and buccal mucosal graft was done from left side of intraoral cavity wall. Results: Flap and graft survived without any necrosis but some nail bed could not be covered with flap due to insufficient flap size. All wounds healed well and did not present any severe adversary symptoms. Conclusion: DAP flap with mucosal graft is an effective method that we can easily apply in reconstruction of fingertip injury. We suggest that the combination of the two procedures makes good functional and cosmetic outcome compared to the usual manner, especially in cases of nail bed injury without distal phalanx bone defect.

• Korean Journal of Head & Neck Oncology
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• v.36 no.1
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• pp.27-31
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• 2020

The midline nasal dermoid cysts are rare congenital neoplasms, which are diagnosed frequently in childhood. Masses are often noticeable at birth gaining size over time with recurrent infections and usually arise from the nasal cavity or lower 1/3 of the nasal dorsum. CT scan as the primary investigation is helpful to determine accurately the size and extent of the lesion as well as the integrity of adjacent bony structures. MRI scan is recommended to rule out an intracranial extension or sinus tracts. Treatment of choice is the complete surgical excision preserving the cyst wall. Here in, we present an unusual case of nasofrontal dermoid cyst in a 19-year-old boy without radiographic evidence of transcranial extension. In this case, we surgically removed nasofrontal dermoid cyst via transcolumellar approach. We also corrected saddle nose deformity after mass removal. Therefore, in this case, we experienced a successful case in which the nasofrontal dermoid cyst was totally removed without facial scar and deformity.

• Journal of Veterinary Clinics
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• v.29 no.4
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• pp.348-351
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• 2012

A vaginal speculum examination of a 17-month-old Holstein heifer with a history of repeated artificial insemination (AI) failures via the cranial vagina revealed the presence of an intact hymen (imperforate hymen) beyond the external urethral orifice, which resembled the vaginal wall. An ultrasonographic examination detected hypoechoic fluid within the vaginal cavity between the intact hymen and the cervix, indicating the presence of hydrocolpos. After sedation and epidural anesthesia, the intact hymen was incised using a scalpel and scissors and removed, while the incised portions were sutured using a simple interrupted method. The heifer became pregnant after three consecutive estruses with the intervals of approximately 20 days and concomitant AIs. The heifer gave birth to a healthy male calf with no complications after a 291-day gestation period. This case reports the presence of an imperforate hymen with hydrocolpos in a Holstein heifer, followed by successful insemination, conception and delivery after removal of the imperforate hymen.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.77-85
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• 2000

Streptococcus mutans is the most important causative bacteria of dental caries among the oral bacteria. Lactococcus lactis 1370 was isolated from the oral cavity of child. The effect of Lactococcus lactis 1370 on the formation of artificial plaque by Streptococcus mutans was studied. 1. The insoluble substances and bacteria were much more attached on the wall of disposable cuvette in the culture of Streptococcus mutans than in the combined culture of Streptococcus mutans and Lactococcus lactis 1370. 2. The mean weight of produced artificial plaque on the wires in the beaker was 131.7 mg in the culture of Streptococcus mutans only, whereas being reduced to 6.4 mg in the combined culture of Streptococcus mutans and Lactococcus lactis 1370 (p<0.05). The viable cell didn't show the significant difference between them after culturing. 3. When Streptococcus mutans was cultured in the media containing culture supernatant of Lactococcus lactis 1370 cultured in M17 broth containing 0.5% yeast extract and 5% sucrose, the mean weight of produced artificial plaque was 8.0 mg on the wires, whereas being 125.4 mg in the media without culture supernatant of Lactococcus lactis 1370 (p<0.05). The viable cell didn't show the significant difference between them after culturing. 4. When Streptococcus mutans was cultured in the media containing soluble polymer produced by Lactococcus lactis 1370, the mean weight of produced artificial plaque was significantly reduced compared with being cultured in the media without soluble polymer (p<0.05). The viable cell didn't show the significant difference between them after culturing. 5. The soluble polymer produced by Lactococcus lactis 1370 was glucan. 6. The glucan produced by Lactococcus lactis 1370 was water-soluble glucan containing ${\alpha}$-1,6-glucose linkage as the main linkage. These results suggest that the artificial plaque formed by Streptococcus mutans is inhibited by water-soluble glucan produced by Lactococcus lactis 1370.

• Journal of fish pathology
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• v.16 no.1
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• pp.13-21
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• 2003

The infection characteristics with scuticociliates at on-land rearing farms and hatcheries of flounder, Paralithys olivaceus was investigated during the year of 2001 by juvenile infection routes. When culture tanks for living food organisms such as chlorella, rotifer, and Artemia were searched, scuticocilates were detected both in live and dead rotifer, and at the dregs of culture tank bottoms at almost hatcheries. When rotifer infected with scuticocilates fed on fish larvae, lots of scuticocilate were inhabited at the bottom of fry rearing tanks. After feeding on scuticocilates-infected rotifer on fish larvae, first infection was detected at 10 days after bottom dwelling or 40 days old after hatching. By histopathological examination we confirmed the infection route of eyeball or brain contamination was that the ciliate worms digged through mouth and front part of the dosal fin cuticle, transferred into eyeball along the epithelium and muscle tissue, and reached finally into brain by the muscle and nerve tissue. The infection of internal organs was clarified into two routes. The first route was started from the infection at ventral and anal fin rays by the worms, and reached at the anus and rectum through the epithelium and muscle tissue. The second route was initiated from the infection at urinary organ and reached into the rectum epithelium cells, inner wall of intestine, abdominal cavity, pancreas, kidney, and pancreas. At seed production farms where fish larvae fed on scuticocilate-free rotifer, the worms were not detected not only at the food organisms culture tanks and juvenile rearing tanks but also larval flounder less than 7cm in total length.

• Journal of computational fluids engineering
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• v.18 no.4
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• pp.25-34
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• 2013

A numerical study of a laminar natural convection of the CuO-water nanofluid in a square cavity using the Buongiorno's nonhomogeneous model is presented. All the governing equations including the volume fraction equation are discretized on a cell-centered, non-uniform grid employing the finite-volume method with a primitive variable formulation. Calculations are performed over a range of Rayleigh numbers and volume fractions of the nanopartile. From the computed results, it is shown that both the homogeneous and nonhomogeneous models predict the deterioration of the natural convection heat transfer well with an increase of the volume fraction of nanoparticle at the same Rayleigh number, which was observed in the previous experimental studies. It is also shown that the differences in the computed results of the average Nusselt number at the wall between the homogeneous and nonhomogeneous models are very small, and this indicates that the slip mechanism of the Brown diffusion and thermophoresis effects are negligible in the laminar natural convection of the nanofluid. The degradation of the heat transfer with an increase of the volume fraction of the nanoparticle in the natural convection of nanofluid is due to the increase of the viscosity and the decrease of the thermal expansion coefficient and the specific heat. It is clarified in the present study that the previous controversies between the numerical and experimental studies are owing to the different definitions of the Nusselt number.