• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.2
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• pp.150-156
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• 2015

In this study, the effects of different mix proportions and fire scenarios (exposure temperatures and post-fire-curing periods) on fire-damaged concrete were analyzed using a nonlinear resonance vibration method based on nonlinear acoustics. The hysteretic nonlinearity parameter was obtained, which can sensitively reflect the damage level of fire-damaged concrete. In addition, a splitting tensile strength test was performed on each fire-damaged specimen to evaluate the residual property. Using the results, a prediction model for estimating the residual strength of fire-damaged concrete was proposed on the basis of the correlation between the hysteretic nonlinearity parameter and the ratio of splitting tensile strength.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.205.2-205
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• 2003

가정에서는 쌀을 소비할 때 외기 조건 특히, 하절기와 같이 외기 온도가 높을 경우 함수율 감소, 지방산가 증가 및 해충발생 등 품질 손상이 급격히 발생한다. 따라서, 가정에서 쌀을 소비할 때 쌀의 품온을 가능한 낮춰 안전하게 저장하는 방법이 필요하다. 본 연구는 가정용 냉각쌀통을 이용하여 저온에서 쌀을 저장하면서 저장기간 중 품질변화를 측정하여 저온저장특성을 구명하는데 목적이 있다. 가정용 냉각쌀통은 매직 쌀장고(MRH-2501, Tongyang)를 이용하였으며, 대조구로 상온($25^{\circ}C$)에서 쌀을 14주간 저장하면서 1주일 간격으로 시료를 채취하여 함수율, 지방산가, 색도 및 표면변화를 측정하였다. 저장기간이 경과함에 따라 쌀의 함수율은 냉각쌀통의 경우 1.5%(w.b.), 상온저장의 경우 2.1%(w.b.)가 감소하였다. 지방산가는 냉각쌀통에서 저장 14주 후15.1(mg KOH/100g)로 나타났고, 상온저장에서는 8주 후 24.2, 14주 후에는 40.9(mg KOH/100g)로 급격히 증가하였다. 쌀의 색도는 저장기간이 경과함에 따라 증가하는 경향으로 나타났으며, 상온저장이 냉각쌀통에 비해 현저히 높게 증가하였으며, 저장 8주 후부터는 유의적인 차이를 나타내었다. 쌀의 표면에 세포벽은 냉각쌀통에 비해 상온저장에서 저장기간이 경과함에 따라 뚜렷하게 나타났다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.78-78
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• 1993

1) 측좌핵파괴 후 muricide를 비롯하여 startle, struggle등의 정동행동의 변화가 뇌손상 초기에는 현저히 발현되나 muricide를 제외하고 기간경과와 함께 점차 감소한다. 2) 봉선핵파괴 동물은 muricide, moose-eating behavior 등의 극심한 정동행동의 변화를 유발한다. 3) 측자핵파괴로 유발된 muricide는 1-DOPA, nomifensine, desipramine 등에 의하여 현저히 억제되었으나 HPD 에는 감수성이 낮았다. 봉선핵파괴로 유발된 muricide는 L-5-HTP, 4) 봉선핵파괴로 유발된 muricide는 L-5-HTP, clomipramine, nomifensine 등에 의하여 현저하게 억제되었다.

• Journal of Chest Surgery
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• v.37 no.9
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• pp.774-780
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• 2004

Although traumatic thoracic aortic rupture is potentially a fatal condition requiring surgical attention, the presence of concomitant injury involving other parts of the body may greatly increase the risk of cardio-pulmonary bypass. We report our experience of treating associated injuries prior to the thoracic aortic rupture in these patients. Material and Method: From 1997 to 2003, the medical records of 24 traumatic aortic rupture patients were retrospectively reviewed and checked for the presence of associated injury, surgical method, postoperative course, and complications. Surgical technique comprised thoracotomy with proximal anastomosis under deep hypothermic circulatory arrest followed by side arm perfusion to reestablish cerebral circulation. CSF drainage was performed to prevent lower extremity paraplegia. Result： Major concomitant injuries (n=83) were noted in all of the reviewed patients, Of these, there were 49 thoracic injuries, 18 musculoskeletal injuries, and 13 abdominal injuries, Operations for associated injuries (n=16) were performed in 12 patients on mean 7.6$\pm$12.6 days following the injury. The diagnosis of aortic rupture at the time of injury was detected in only 18 patients. Delayed surgery of the thoracic aorta was performed on average 695$\pm$1350 days after injury and there were no deaths or progression of rupture in any of these patients during the observation period. There were no operative deaths and no major postoperative complications. Conclusion: Treating concomitant major injuries prior to the aortic injury in traumatic aortic rupture may reduce surgical mortality and morbidity.

• Journal of Life Science
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• v.13 no.6
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• pp.950-957
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• 2003

The purpose of this study is to classify the contrast group and experiment group of a male white rat, and to identify a result of NFG's change that press the sciatic nerves injured peripheral ones for curing 1day, 3days, 5days and 7days. In contrast group, the nerve cells of immune-reaction were increased on 1 day and they were decreased for 3 days, 5 days, 7 days as a normal one. In experiment group, they were increased on 1 day but, decreased for 3 days, 5 days, 7 days more than contrast group. In conclusion, it is certain that the Needle TENS can make a NFG decrease and effect on the therapy.

• Journal of the Korean Institute of Gas
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• v.7 no.2 s.19
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• pp.1-6
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• 2003

In this work, procedure evaluating failure modes such as pipe rupture, large scale leak, and small scale leak was suggested using equations to assess remaining strength by corrosion failure. Additionally, the method to predict probability of failure was suggested according to the aforementioned failure modes, and by combining data on corrosion rate, probability of long-term failure can be induced. This work will be very useful in predicting lifetime or exchanging period of pipeline.

• Journal of the Korean Arthroscopy Society
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• v.11 no.1
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• pp.13-19
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• 2007

Purpose: We investigated the natural history of acute, isolated posterior cruciate ligament injuries treated conservatively. Materials and Methods: Between February 1999 and October 2006, we evaluated retrospectively the results of acute, isolated posterior cruciate ligament injuries treated conservatively. The subjects consisted of 21 patients. At initial and follow up visits physical examination, $KT-2000^{TM}$ arthrometer and MRI were performed to assess improvement on the knee stability and continuity of the posterior cruciate ligament. IKDC (International Knee Documentation Committee) knee scoring and quadriceps muscle strength were also checked in all population. Comparing the results of initial and follow up examinations we assessed the natural history of acute, isolated posterior cruciate ligament injuries treated conservatively. The mean follow up period was 22.7 months. Results: The posterior drawer test showed 14 cases of Grade I, 6 cases of Grade II and 1 case of Grade III progressing 18 cases of Grade I and 3 cases of Grade II. The mean difference of 5.7mm by $KT-2000^{TM}$ arthrometer was changed Into 2.7mm and the continuity of posterior cruciate ligament initially checked by 48.1% on MRI increased to 69.7%. The mean quadriceps muscle strength was grade 'Good' and mean IKDC knee score was nearly grade 'A'. Conclusion: Our study suggests that patients with acute, isolated posterior cruciate ligament injuries treated conservatively may get good clinical outcomes on clinical situation and MRI.

• Applied Microscopy
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• v.32 no.1
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• pp.1-8
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• 2002

To confirm the effect of electroacupuncture on the regeneration of injured peripheral nerve, the change of evoked potential in the sciatic nerve, the change of enzyme activity in the spinal cord, and morphological change of injured sciatic nerve were examined comparatively in acupuncture group (AG) and control group (CG) after sciatic nerve of guinea pig was injured by purpose. The value of evoked potential after injury of the sciatic nerve was increased in both AG and CG, but the increase rate of that was higher in AG than CG. Acid phosphatase activity of the spinal cord was increased in 1CG and 2AG, but shown are tendency to return to the normal state as time went by. Ultrastructural recovering rate of the injured sciatic nerve was higher in AG than CG. Also, there was developed only adipose tissue in sciatic nerve of AG. As mentioned above, the effect of electroacupuncture on the regeneration of injured peripheral nerve was confirmed experimentally by change of evoked potential, acid phosphatase and ultrastructure. Especially, the effect of electroacupuncture was appeared clearly in an early stage than other treatment stages.

• Journal of Chest Surgery
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• v.41 no.6
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• pp.695-702
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• 2008

Background: The choice between a bioprosthetic and a mechanical valve is an important decision in cardiac valve surgery, and the durability of the tissue valve is a major decision factor. We retrospectively evaluated the midterm results of bioprosthetic valve replacement in the mitral position. Material and Method: The subjects were all patients who had undergone mitral bioprosthesis replacement between July 1989 and August 200.7. Among the 216 patients, there were 236 surgical cases. The mean age was $63{\pm}15$ years, and the male to female ratio was 1 : 3. We retrospectively analyzed hospital and outpatient records such that the total follow-up duration amounted to 760.2 patient-years, and the mean follow-up duration was $41.9{\pm}40.7$ months (range $0{\sim}212$ months). Result: Early death occurred in 18 patients (8.3%), and 13 of these underwent concomitant cardiac procedures. The survival rate after 5 years was $79.9{\pm}3.5%$, and the survival rate after 8 years was $65.5{\pm}5.5%$, while freedom from structural valve deterioration (SVD) was $96.2{\pm}2.2%$ at 5 years and $85.9{\pm}5.3%$ at 8 years. Freedom from reoperation was $90.6{\pm}1.7%$ at 5 years and $90.4{\pm}4.2%$ at 8 years, while freedom from reoperation for SVD was $98.1{\pm}1.2%$ at 5 years and $92.3{\pm}4.1%$ at 8 years. On multivariate analysis of preoperative risk factors, small valve size (between 25mm and 27mm) was a significant risk factor for reoperation, and low LV ejection fraction (<40%) was a significant risk factor for SVD and mortality. Conclusion: Survival and freedom from reoperation for SVD in mitral bioprosthesis replacement had acceptable midterm results, but freedom from SVD Was relatively low. In particular, since SVD increased sharply at the eighth postoperative year, frequent follow-up and echocardiograms around that time will be helpful for the early detection of SVD. It will be necessary to conduct further studies involving long-term follow-up and more patients.

• Radiation Oncology Journal
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• v.5 no.1
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• pp.1-11
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• 1987

Total 390 mice were irradiated with $2{\times}3cm$ abdominal field and $200{\times}5/wk$ regimen with orthovoltage x-ray machine. All animals were divided into 2 large groups, damage and recovery, and histopathologic changes were analyzed at various total dose level (1,000 cCy-5,000 cCy) and intervals (1 week-15 weeks). Almost acute changes such as decreased mitotic activity, villi shortening and focal erosion of mucosa recovered within 1-2 weeks in 1,000-3,000 cGy irradiated group but mild changes persisted in 4,000 and 5,000 cCy irradiated groups. Chronic delayed changes such as thickening of vessel wall with focal thrombosis, submucosal fibrosis, mucosal atrophy and chronic ulcer were observed from 2-3 week specimens in 4,000 and 5,000 cGy groups, These late changes recovered slightly, as increasing time intervals after irradiation but mild, persistant changes were observed throught all follow up period. These data suggest hat even 4,000 cCy is not completely safe for possible permanent damage and judicious modificiation of total dose, dose rate, fraction size, and field size should be considered for better results.