• Journal of Chest Surgery
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• v.26 no.8
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• pp.595-603
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• 1993

We analysed 60 consecutive patients who got Senning operation for transposition of the great arteries [TGA] with or without ventricular septal defects [VSD]. There were 41 simple TGA [group I] and 19 TGA with VSD [Group II], the operative mortality was 20 % [in group I 4.9 %, group II 52.6 %]. Among the survivors [n=48], the mean follow-up period was 7 years [range, 1 year to 13.5 years] and the actuarial survival rate at 13 years were 95 % in group I and 42 % in group II. Preoperative high left ventricular pressure and high pulmonary arterial pressure affected the surviving [p<0.01]. There occurred various type of arrhythmia like junctional rhythm, first degree atrioventricular [AV] block, sick sinus syndrome and complete AV block, and we inserted 2 permanent pacemakers for these patients. The incidence of arrhythmia were 28.2 % [11/39] in group I and 55.6 % [5/9] in group II, and the actuarial freedom from arrhythmia at 13 years after operation was 66 % [71 % in group I, 44 % in group II]. Increased aortic cross clamping time had affected the development of arrhythmia [p<0.05] which meant the complexity of the operation. The total incidence of left ventricular outflow tract obstruction [LVOTO] was 31.3 % [15/48], but only 3 patients [6.25 %] showed the significant gradient requiring reoperation. The pulmonary venous pathway obstruction [PVO] were found in 3 patients, all in group I, and among them only one required the reoperation. The estimated freedom from PVO was 89 % at 13 years [87 % in group I, 100 % in group II], but we couldn`t find any significant systemic venous obstruction in our series. There occurred 27.1 % [13/48] mild degree tricuspid valve regurgitation without necessary surgical correction. We experienced 14.6 % [7/48] reoperation rate: 3 residual VSD, 3 LVOTO, 1 PVO, 3 atrial baffle leakage. For this high incidence of complication rate after Senning operation and high mortality in TGA with VSD, We do not use this kind of surgical modality any more and do the Jatene operation for all the TGA patients since several years ago.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04a
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• pp.44-44
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• 2008

To date, rubbing has been widely used to align LC molecules uniformly. Although rubbing can be simple, it has fundamental problems such as the generation of defects by dust and static electricity, and difficulty in achieving a uniform LC alignment on a large substrate. Therefore, non contact alignment has been investigated. Ion beam induced alignment method, which provides controllability, nonstop process, and high resolution display. In this study, we investigated liquid crystal (LC) alignment with ion beam (IB) that non contact alignment technique on polyimide and electro-optical characteristics of twisted nematic (TN)-liquid crystal display (LCD) on the polyimide under various ion beam angles. In this experiment, Polyimide layer was coated on glass by spin-coating and Voltage-transmittance(VT) and response time characteristics of the TN cell were measured by a LCD evaluation system. The good characteristics of the nematic liquid crystal (NLC) alignment with the ion beam exposure polyimide surface was observed. The tilt angle of NLC on the PI surface with ion beam exposure can be measured under $1^{\circ}$ for all of irradiation angles. In addition, it can be achieved the good EO properties, and residual DC property of the ion beam aligned TN cell on polyimide surface.

• The Journal of Korean Physical Therapy
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• v.17 no.1
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• pp.43-68
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• 2005

The purpose of this study was to report the physical status of adult with cerebral palsy who live in local community areas including Seoul, Busan, Daegu in Republic of Korea at 2004. 202-individuals with cerebral palsy(140 male, 62 female; mean age 31.9 years; range 19 to 64 years) were surveyed. Measures included a 29-item self-reported health status measure focusing on musculoskeletal status and functional performances. Adult cerebral palsy required continuous management for musculoskeletal and ambulatory function through therapeutic approach. This survey is restricted to population who had cared in welfare center for cerebral palsy in local community, so it needs to investigate home-residual adults with cerebral palsy and the population in rural community. The results were as follows: 1. Participants reported that they had a limitation of a daily of life activity due to musculoskeletal pain($43\%$), there was significant differences between a limitation of a daily of life activity and the decreased ambulatory function(p<.05). 2. Thirty six point six percentile of participants had the decreased ADL function, it was significant related with the impaired body location(p<.05) 3. Thirty nine point one percentile of participants who can independently gait had the decreased ambulatory function, it was significant differences with the usage of ambulatory assistive devices(p<.05). 4. There was significant differences ambulatory function both the body region with impairment and a grade of disability(p<.05). 5. Sixteen point three percentile of participants could not ambulate any more, there was significant differences between a age and a point of time for non-ambulation(p<.05). 6. There was significant differences between ambulatory function and physical activity(p<.05).

• Journal of Ocean Engineering and Technology
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• v.25 no.4
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• pp.18-22
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• 2011

The Ranking source panel method was used to predict the flow phenomenon of a ship with a goose-neck type bulbous bow penetrating the free surface. The non-linearity of the free surface boundary condition was fully satisfied using an iterative calculation method, and the raised panel method was adopted to obtain a more stable solution at each iteration step. The panel cutting method was applied to generate a hull calculation grid at each iteration step, including the first step. At that time, the nose of the goose-neck type bulbous bow was divided by the free surface and the free surface panel was modified at each iteration step using the variable free surface panel method. Numerical calculations were performed to investigate the validity and efficiency of the applied numerical algorithm using the 3600 TEU container carrier. The computed wave resistance coefficients were compared with the experimentally achieved residual resistance coefficients.

• Journal of Korean Neurosurgical Society
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• v.58 no.1
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• pp.83-88
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• 2015

Organized hematoma is a rare complication that can develop following gamma knife radiosurgery (GKS) for cerebral arteriovenous malformation (AVM). Here, we describe 5 patients with growing organized hematomas that developed from completely obliterated AVMs several years after GKS. The patients were 15, 16, 30, 36, and 38 years old at the time of GKS, respectively, and 3 patients were female. Four AVMs were located in the lobe of the brain, and the remaining AVM were in the thalamus. Between 2-12 years after GKS, patients developed progressive symptoms such intractable headache or hemiparesis and enhancing mass lesions were identified. Follow-up visits revealed the slow expansion of the hematomas and surrounding edema. Steroids were ineffective, and thus surgery was performed. Histology revealed organized hematomas with a capsule, but there was no evidence of residual AVMs or vascular malformation. After surgery, the neurological symptoms of all patients improved and the surrounding edema resolved. However, the hematoma continued to expand and intraventricular hemorrhage developed in 1 patient whose hematoma was only partially removed. GKS for cerebral AVM can be complicated by growing, organized hematomas that develop after complete obliteration. Growing hematomas should be surgically evacuated if they are symptomatic. Radical resection of the hematoma capsule is also strongly recommended.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.51-58
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• 2011

One of the objectives of research on routing methods in wireless sensor networks is maximizing the energy life of sensor nodes that have limited energy. In this study, we tried to even energy use in a wireless sensor network by giving a weight to the transition probability of ACS(Ant Colony System), which is commonly used to find the optimal path, based on the amount of energy in a sensor and the distance of the sensor from the sink. The proposed method showed improvement by 46.80% on the average in energy utility in comparison with representative routing method GPSR (Greedy Perimeter Stateless Routing), and its residual energy after operation for a specific length of time was 6.7% more on the average than that in ACS.

• Clinical and Experimental Pediatrics
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• v.63 no.7
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• pp.251-258
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• 2020

Exposure to environmental factors can cause interstitial lung diseases (ILDs); however, such types of ILDs are rare. From 2007 to 2011, an ILD epidemic occurred in South Korea owing to inhalational exposure to toxic chemicals in humidifier disinfectants (HDs). HD-associated ILDs (HD-ILDs) are characterized by rapidly progressing respiratory failure with pulmonary fibrosis and a high mortality rate of 43.8%-58.0%. Although 18.1%-31.1% of the general population used HDs, only a small proportion of HD users were diagnosed with HD-ILDs. This finding suggests that investigation of the pathophysiologies underlying HD-ILDs is needed in addition to the identification of susceptibility to HD-ILDs. Further, there have been several concerns regarding the diverse health effects of exposure to toxic chemicals in HDs, including those that have not been identified, and long-term prognoses in terms of pulmonary function and residual pulmonary lesions observed on follow-up chest images. In this review, we summarize the clinical features, pathologic findings, and changes in radiologic findings over time in patients with HD-ILDs and the results of previous experimental research on the mechanisms underlying the effects of toxic chemicals in HDs. Studies are currently underway to identify the pathophysiologies of HD-ILDs and possible health effects of exposure to HDs along with the development of targeted therapeutic strategies. The experience of identification of HD-ILDs has encouraged stricter control of safe chemicals in everyday life.

• Biomedical Science Letters
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• v.22 no.4
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• pp.140-149
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• 2016

All pesticides must be assessed strictly whether safe or not when agricultural operators are exposed to the pesticides in farmland. A pesticide is commonly regarded as safe when estimated dermal absorption amount is lower than the acceptable operator's exposure level (AOEL). In this study, dermal absorption rate of chlorpyrifos, a widely used organophosphate insecticide, was investigated using rat dermal tissue model. Chlorpyrifos wettable powder solved in water (250, 500 and 2,500 ppm) was applied to freshly excised rat dermal slices ($341{\sim}413{\mu}m$ thickness) on static Franz diffusion cells at $32^{\circ}C$ for 6 hours. After exposure period of 6 hours, and then washing-at residual amount of chlorpyrifos was analyzed in dermal tissues, tape strips, washing solution, washing swabs of receptor bottles and receptor fluids at 1, 2, 4, 8 and 24 hours. Chlorpyrifos was only detected in dermal tissue but not found in receptor fluid at each concentration and time point, and the absorption rate of 250, 500 and 2,500 ppm was 2.36%, 1.96% and 1.69%, respectively. The estimated exposure level of chlorpyrifos was calculated as 0.012 mg/kg bw/day. The health risk for farmers in this condition is a level of concern because the estimated exposure level is 12 times higher than AOEL 0.001 mg/kg bw/day. However, actual health risk will be alleviated than estimated because absorbed chlorpyrifos is not permeated into internal body system and only retained in skin layer.

• BMB Reports
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• v.32 no.5
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• pp.515-520
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• 1999

Incubation of two types of glutamate dehydrogenase isoproteins from bovine brain with the arginine-specific dicarbonyl reagent phenylglyoxal resulted in a biphasic loss of enzyme activity. Reaction of the glutamate dehydrogenase isoproteins with phenylglyoxal caused a rapid loss of 53~62% of the enzyme activities and modification of two residues of arginine per enzyme subunit. Prolonged incubation of the glutamate dehydrogenase isoproteins with phenylglyoxal resulted in the modification of an additional four residues of arginine per enzyme subunit without further loss of the residual activities. Partial protection against inactivation was provided by the coenzyme NADH or substrate 2-oxoglutarate. The most marked decrease in the rate of inactivation was observed by the combined addition of NADH and 2-oxoglutarate, suggesting that the first two modified arginine residues are in the vicinity of the catalytic site. However, inactivation of the glutamate dehydrogenase isoproteins by phenylglyoxal appears to be partial with approximately 40% activity remained after an extended reaction time with excess reagent, suggesting that the modified arginine residues may not be directly involved in catalysis. The lack of complete protection by substrates also suggest the possibility that the modified arginine residues are not directly involved at the active site, and the partial loss of activity by the modification of arginine residues may be due to a conformational change. There were no significant differences between the two glutamate dehydrogenase isoproteins in sensitivities to inactivation by phenylglyoxal, indicating that the microenvironmental structures of the glutamate dehydrogenase isoproteins are very similar to each other.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.8
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• pp.891-898
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• 2005

Inertia welding is a solid-state welding process in which butt welds in materials are made in bar and in ring form at the joint race, and energy required lot welding is obtained from a rotating flywheel. The stored energy is converted to frictional heat at the interface under axial load. The quality of the welded joint depends on many parameters, including axial force, initial revolution speed and energy amount of upset. working time, and residual stresses in the joint. Inertia welding was conducted to make the large exhaust valve spindle for low speed marine diesel engine. superalloy Nimonic 80A for valve head of 540mm and high alloy SNCrW for valve stem of 115mm. Due to different material characteristics such as, thermal conductivity and flow stress. on the two sides of the weld interface, modeling is crucial in determining the optimal weld geometry and Parameters. FE simulation was performed by the commercial code DEFORM-2D. A good agreement between the Predicted and actual welded shape is observed. It is expected that modeling will significantly reduce the number of experimental trials needed to determine the weld parameters. especially for welds for which are very expensive materials or large shaft. Many kinds of tests, including macro and microstructure observation, chemical composition tensile , hardness and fatigue test , are conducted to evaluate the qualify of welded joints. Based on the results of the tests it can be concluded that the inertia welding joints of the superalloy exhaust valve spindle are better properties than the material specification of SNCrW.