• Journal of Mechanical Science and Technology
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• v.19 no.9
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• pp.1811-1820
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• 2005

Thermo-acoustic instability of methane/ air flames in an industrial gas-turbine combustor is numerically investigated adopting CFD analysis. The combustor has 37 EV burners through which methane and air are mixed and then injected into the chamber. First, steady fuel! air mixing and flow characteristics established by the burner are investigated by numerical analysis with single burner. And then, based on information on the flow data, the burners are modeled numerically via equivalent swirlers, which facilitates the numerical analysis with the whole combustion system including the chamber and numerous burners. Finally, reactive flow fields within the chamber are investigated numerically by unsteady analysis and thereby, spontaneous instability is simulated. Based on the numerical results, scaling analysis is conducted to find out the instability mechanism in the combustor and the passive control method to suppress the instability is proposed and verified numerically.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1119-1123
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• 2014

Head and neck cancers (HNC) are extremely complex disease types and it is likely that chromosomal instability is involved in the genetic mechanisms of its genesis. However, there is little information regarding the background levels of chromosome instability in these patients. In this pilot study, we examined spontaneous chromosome instability in short-term lymphocyte cultures (72 hours) from 72 study subjects - 36 newly diagnosed HNC squamous cell carcinoma patients and 36 healthy ethnic controls. We estimated chromosome instability (CIN) using chromosomal aberration (CA) analysis and nuclear level anomalies using the Cytokinesis Block Micronucleus Cytome Assay (CBMN Cyt Assay). The proliferation rates in cultures of peripheral blood lymphocytes (PBL) were assessed by calculating the Cytokinesis Block Proliferation Index (CBPI). Our results showed a significantly higher mean level of spontaneous chromosome type aberrations (CSAs), chromatid type aberration (CTAs) dicentric chromosomes (DIC) and chromosome aneuploidy (CANE UP) in patients (CSAs, $0.0294{\pm}0.0038$; CTAs, $0.0925{\pm}0.0060$; DICs, $0.0213{\pm}0.0003$; and CANE UPs, $0.0308{\pm}0.0035$) compared to controls (CSAs, $0.0005{\pm}0.0003$; CTAs, $0.0058{\pm}0.0015$; DICs, $0.0005{\pm}0.0003$; and CANEUPs, $0.0052{\pm}0.0013$) where p<0.001l. Similarly, spontaneous nuclear anomalies showed significantly higher mean level of micronuclei (MNi), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) among cases (MNi, $0.01867{\pm}0.00108$; NPBs, $0.0156{\pm}0.00234$; NBUDs, $0.00658{\pm}0.00068$) compared with controls (MNi, $0.00027{\pm}0.00009$; NPBs, $0.00002{\pm}0.00002$; NBUDs, $0.00011{\pm}0.00007$).The evaluation of CBPI supported genomic instability in the peripheral blood lymphocytes showing a significantly lower proliferation rate in HNC patients ($1.525{\pm}0.005552$) compared to healthy subjects ($1.686{\pm}0.009520$) (p<0.0001). In conclusion, our preliminary results showed that visible spontaneous genomic instability and low rate proliferation in the cultured peripheral lymphocytes of solid tumors could be biomarkers to predict malignancy in early stages.

• Journal of Korean Neurosurgical Society
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• v.39 no.3
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• pp.221-223
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• 2006

We report the case of a patient with a retro-odontoid synovial cyst, coupled with os odontoideum and atlantoaxial instability. We observed the regression of the cyst after C1-2 transarticular screw fixation and posterior wiring without direct surgical excision of the cyst on the follow-up MR images, which were obtained two and three months postoperatively. The myelopathic symptoms and signs of this patient were resolved by degrees.

• Journal of the Korean Arthroscopy Society
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• v.1 no.1
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• pp.112-115
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• 1997

While the cruciate ligament has a profuse vascular response following injury, spontaneous repair does not occur. This may result from the fact that synovial fluid dilution of the hematoma following injury prevents the formation of a fibrin clot and thus the initiation of the healing mechanism. Another theory suggests that the dynamic nature of the fascicles of the anterior cruciate ligament(ACL) through even small ranges of motion prohibits spontaneous union to these fibers. But we experienced two cases of spontaneous healing of partially injured ACL. Initially they showed more than grade II anterior instability. 6 mm difference by stress roentgenographs(pull view) and difference of 8 mm by KT 1000TM arthrometer between the ACL injured knee and normal side knee. Lax, nearly complete tear of ACL and synovial bleeding were noted during arthroscopic examination but the continuity of synovial membrane was seemed to be intact. These cases were treated by conservative management rather than reconstructive procedure. Postoperatively they showed excellent clinical results, no anterior instability and unlimited athletic activity. Based on our clinical experience. we think that cruciate ligament has the spontaneous healing potential in acute stage and middle aged patient. We consider the microfracture technique and initial immobilization for accelleration of healing response of the ACL.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.70.1-70.1
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• 2019

Multiple-harmonic electron cyclotron emissions, often known in the literature as the (n + 1∕2)fce emissions, are a common occurrence in the magnetosphere. These emissions are often interpreted in terms of the Bernstein mode instability driven by the electron loss cone velocity distribution function. Alternatively, they can be interpreted as quasi-thermal emission of electrostatic fluctuations in magnetized plasmas. The present paper carries out a one-dimensional relativistic electromagnetic particle-in-cell simulation and also employs a reduced quasi-linear kinetic theoretical analysis in order to compare against the simulation. It is found that the Bernstein mode instability is indeed excited by the loss cone distribution of electrons, but the saturation level of the electrostatic mode is quite low, and that the effects of instability on the electrons is rather minimal. This supports the interpretation of multiple-harmonic emission in the context of the spontaneous emission and reabsorption in quasi-thermal magnetized plasma in the magnetosphere.

• Journal of Korean Neurosurgical Society
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• v.42 no.2
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• pp.125-128
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• 2007

The incidence of spontaneous recanalization after traumatic internal carotid artery occlusion is very rare. We have experienced a case of spontaneous recanalization after a traumatic internal carotid artery occlusion. A 5-year-old boy developed contra-lateral hemiparesis and dysphasia after a blunt injury on the head and neck. He had a complete left internal carotid artery occlusion which was diagnosed through angiography. We treated the patient with an anti platelet agent and rehabilitation. Six months later, he regained motor power of right extremities, language ability, and revisualization of internal carotid artery on the follow-up magnetic angiography. We confirmed a recanalization of injured internal carotid artery on the conventional cerebral angiography which was performed one year later. We suggest conservative treatment with serial angiographic studies as a possible option of traumatic internal carotid artery occlusion even though there is hemodynamic instability.

• Journal of Chest Surgery
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• v.33 no.10
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• pp.812-816
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• 2000

Background ; To evaluate the efficacy of Fibrin glue to decrease recurrence in video-assisted thoracoscopic surgery(VATS) for a treatment of spontaneous penumothorax. Material and Method : All medical records of 17 patients who underwent a thoracoscopic wedge resections of bullae with stapling device with Fibrin glue in our institute between May 1998 and December 1999 were reviewed. variables analyzed include affected sites primary indication of VATS. duration from admission to discharge duration of postoperative stay duration of chest tube drainage recurrence and complication. There were 16 men and 1 woman. Result : There was no evidence of hemodynamic instability or arterial blood gas abnormalities encountered during the procedure. Mean age at the time of the VATS was 26.9 years (range 15 to 61 years) The mean duration from admission to discharge was 7.8 days and mean postoperative stay was 5.1days mean chest tube indwelling period was 4..0 days. There was no recurrence of pneumothorx. Conclusion : Thoracoscopic wedge resections with introduction of fibrin glue are safe and effective and requires only a short hospital stay. We believe that this thoracoscopic technique will further simplify the surgical treatment of pneumothorax.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.190-193
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• 1998

We experienced a case of primary sternal tuberculosis with destroyed midsternum and bony defect. An 22-year-old female was admitted to our hospital two times for severe sternal pain and spontaneous fracture without history of trauma. On hospital admission, chest X-ray and chest CT showed destruction of midsternum and soft tissue swelling. Fine needle aspiration cytology revealed tuberculous osteomyelitis with cold abscess. And the patient was treated with usual anti-tubeculosis medication for preoperative preparation. At operation, we confirmed midsternal destruction with cold abscess and multiple sinus tracts. After removal of diseased sternal segment and cold abscess, we performed sternal reconstruction with autologus iliac bone graft. The pathologic report was compatible with tuberculous osteomyelitis and caseous necrosis The postoperative course was smooth and uneventful, and she remains well without sternal instability two months later.

• Journal of Korean Medicine Rehabilitation
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• v.26 no.3
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• pp.171-181
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• 2016

Objectives The purpose of this study is to investigate and report the effectiveness of Hominis Placenta pharmacopuncture treatment for chronic ankle sprain. Methods 2 patients are treated at Dept. of Korean Medicine, the Armed Forces Busan Hospital, diagnosed as thinning of anterior talofibular ligament (ATFL), suggestive of partial tear and anterior tibiofibular ligament partial tear. They are treated with Hominis Placenta pharmacopuncture. Each cases are measured and assessed by ankle hindfoot scale (AHS), visual analgue scale (VAS), cumberland ankle instability tool (CAIT) scores. Results 2 patients of chronic disease of ankle sprain have a different kind of diagnoses they have. After treatment of Hominis placenta pharmacopuncture, spontaneous pain is decreased and ankle instability, ankle functions are increased significantly. Conclusions Hominis placenta Pharmacopuncture has a effect on chronic ankle sprain.

• Physical Therapy Rehabilitation Science
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• v.10 no.1
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• pp.1-9
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• 2021

Objective: Joint mobilization for arthrokinematics altered by the positional fault of chronic ankle instability (CAI) is an effective intervention for stabilization. In this study, we compared the effects of ankle dorsi flexion range of motion (DFROM) and dynamic balance ability (DBA) in CAI patients via passive joint mobilization (PJM), a method traditionally performed in previous studies, and active joint mobilization (AJM), a method that can have a greater effect on cortical excitability with spontaneous movements. Design: Single-blind two-arm randomized controlled trial Methods: A total of 30 participants were registered: 15 each to the PJM and AJM groups. Each participant received a total of 10 intervention sessions, 10 minutes per session, 5 times a week for 2 weeks. PJM used Maitland's mobilization method to apply joint mobilization with talus in the posterior direction and AJM used an angular joint motion to induce patient's voluntary motion of medial malleolus anterior gliding and lateral malleolus posterior gliding, respectively. DFROM of the ankle was measured by using tape and DBA was evaluated by using the balance system. Results: Significant improvement was observed after intervention in both the PJM and AJM groups except for the DBA-anterior and DBA-right variables of the PJM group. There were statistically significant differences between the AJM and PJM groups in the DFROM, DBA-anterior, DBA-posterior, and DBA-right variables. Conclusions: The overall improvement of DFROM and DBA was found to be more effective in joint mobilization including voluntary movement. When it is accompanied by voluntary movement, it further affects the neuromuscular system of the ankle.