• Journal of Korean Neurosurgical Society
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• v.62 no.2
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• pp.183-192
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• 2019

Objective : The objective of this study was to analyze patient-specific blood flow in ruptured aneurysms using obtained non-Newtonian viscosity and to observe associated hemodynamic features and morphological effects. Methods : Five patients with acute subarachnoid hemorrhage caused by ruptured posterior communicating artery aneurysms were included in the study. Patients' blood samples were measured immediately after enrollment. Computational fluid dynamics (CFD) was conducted to evaluate viscosity distributions and wall shear stress (WSS) distributions using a patient-specific geometric model and shear-thinning viscosity properties. Results : Substantial viscosity change was found at the dome of the aneurysms studied when applying non-Newtonian blood viscosity measured at peak-systole and end-diastole. The maximal WSS of the non-Newtonian model on an aneurysm at peak-systole was approximately 16% lower compared to Newtonian fluid, and most of the hemodynamic features of Newtonian flow at the aneurysms were higher, except for minimal WSS value. However, the differences between the Newtonian and non-Newtonian flow were not statistically significant. Rupture point of an aneurysm showed low WSS regardless of Newtonian or non-Newtonian CFD analyses. Conclusion : By using measured non-Newtonian viscosity and geometry on patient-specific CFD analysis, morphologic differences in hemodynamic features, such as changes in whole blood viscosity and WSS, were observed. Therefore, measured non-Newtonian viscosity might be possibly useful to obtain patient-specific hemodynamic and morphologic result.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.22-24
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• 2007

Waterline extraction is the one of widely used methods for studying changes in tidal flat environment and coastlines using multi-temporal optical images such as Landsat TM and Landsat ETM+. High dynamics of tidal currents and land reclamation which accelerate sedimentation and/or erosion cause waterline change in tidal flats. The amount of sediment deposited or eroded can be evaluated by precisely estimating waterline changes in tidal flats. The objective of this study is to detect the change of waterlines during 17 years and analyze the trends of erosion and sedimentation in the study areas. The Ganghwado tidal flat on the west coast of the Korean Peninsula was selected. The study area is famous for high dynamics of tidal currents and vast tidal flats. Land reclamation which has been carried out on a large scale is also considered as one of elements that have accelerated the environmental changes in this tidal flat. In this study, we acquired 26 waterlines from Landsat TM and Landsat ETM+ images. We extracted the waterline from each satellite image to generate a digital elevation map (DEM) which was used for reference and to compare with the other waterline which was extracted from DEM having a same tide. The result of comparison well depicted the areas of dominant sedimentation and erosion, and general trends of sedimentation and erosion according to sub-regions are also revealed during the investigation time. Results showed that erosion during a decade was dominant at the west of the Southern Ganghwado tidal flat, while sedimentation was dominant at the wide channel between the Southern Ganghwado tidal flat and the Yeongjongdo tidal flat. This area has been commonly affected by high currents and sedimentation energy. Although we were not able to verify the accuracy of the waterline changes, this result clearly showed the waterline change and therefore, the waterline extraction method used in this study has proven as an effective tool for long term tidal change estimation.

• Applied Microscopy
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• v.8 no.1
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• pp.81-90
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• 1978

Introduction of electron microscope in biological and medical sciences change the concept of functional and morphologic unit of biological phenomena from the cell to subcellular unit, and it formulated the basis for molecular biology and pathology. Until recently, electron microscopy has mainly been applied to basic research works. However, practical clinical application of electron microscopy is being actively tried. The major clinical fields in which electron microscopy is helpful or even essential include viral diseases, metabolic diseases, glomerular diseases and in the identification of certain types of neoplasms. A brief introduction of characteristics of each conditions are made to encourage more active application of electron microscopy in clinical medicine.

• Ocean and Polar Research
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• v.30 no.4
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• pp.537-543
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• 2008

The sediment resuspension and diffusion model is an integral part of a sediment transport and morphologic change model. We examined a vertical one-dimensional sediment resuspension and diffusion model using field data collected at about 10-m depth off the Saemangeun $4^{th}$ dike. The field data include waves, currents and suspended sediment concentration near the bed for about a day in May, 2007. The suspended sediment concentration obtained from the 1D model overestimated the observation about two orders of magnitude with single grain size and multiple grain sizes. The incorporation of the bed armoring effect, which adjusts the amount of suspended sediment with the available bed sediment, improved the agreement between the model and observation within a factor of two.

• Journal of Veterinary Clinics
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• v.18 no.2
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• pp.111-115
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• 2001

The water celery, Oenanthe javanica DC., is widely distributed in Korea and the other South East Asian countries. From ancient times, the water celery has widely been used for food or medicine. In herbal medicine, the water celery has a medical actions which are defervescence, diuresis, hypotensor, appetizer. Recently, studies on the water celery are briskly being conducted. For example, studies on the morphologic property and classifications of origin of the water celery, studies on the chemical constituents of the Water celery, studies on the bio activities of the water celery which contains flavonoids. However, there is not studies of hematological changes in dogs administrated the water celery until now. Consicontly, this study was conducted to observe the hematological changes in dogs administrated excessive amount of the water celery concentrated extract for a long period. In this studies, all dogs showed significantly decrease of the RBC, PCV, Hb and MCHC, and increase of the WBC, MCV, GSH and reticulocytes, but did not significantly change in the Met-Hb.

• Toxicological Research
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• v.11 no.2
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• pp.169-173
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• 1995

The effects of tumor necrosis factor alpha $(TNF-{\alpha})$ on growth and tubular formation of bovine aortic endothelial cells were examined using an in vitro angiogenesis model system. The growth of endothelial cells was enhanced in a dose-dependent manner when the cells were cultured with $TNF-{\alpha}$ for 3 days, but $TNF-{\alpha}$, at the concentration of 1 nM or higher, produced a growth inhibition of endothelial cells when the cells were cultured for 8 days. The endothelial cells incubated with $TNF-{\alpha}$ for 48-h exhibited a typical morphologic change. Then, they showed a fibroblastoid organization of overlapping, elongated, and spindle-shaped cells. $TNF-{\alpha}$, at the concentration of O. 1 nM or higher, inhibited the tubular formation of vascular endothelial cells in an in vitro anglogenesis model using a 3-dimensional culture system.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.137-137
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• 2015

The purposed of this work was to observe hydroxyapatite precipitation phenomena on micro-pore formed Ti-Nb alloy by PEO technique. The Ti-30Nb and Ti-30Ta alloys were remelted at least ten times in order to avoid inhomogeneity, and then cylindrical specimens (diameter 10 mm, thickness 4 mm) were cut by using laser from cast ingots of the Ti alloys. Heat treatment was carried out at $1050^{\circ}C$ for 2 h for homogenization in argon atmosphere. The morphologic change of the alloys were examined by X-ray diffractometer (XRD) and field emission scanning electron microscopy (FE-SEM).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.2
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• pp.209-214
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• 1999

Chronic recurrent TMJ dislocation results in difficulty of mastication, speaking, and swallowing due to the limitation of the mandibular movement. Etiologic factors are considered as the looseness of the capsule and ligaments, the decrease of the articular eminence, condylar morphologic change, muscular disharmony near by TMJ, and the decrease of the vertical length of the mandibular ramus. Treatment approach has been suggested that surgical methods are selected for the correction of the etiologic factors when conservative treatments are not effective. Many surgical methods have been reported such as eminectomy, eminence augmentation, condylotomy, and zygomatic arch down fracture technique. We performed the eminence augmentation through interpositional bone graft in chronic recurrent TMJ dislocation. This method leads to favorable postoperative result without recurrence and complication, so we report the case with related references.

• The Journal of Korean Medicine
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• v.29 no.4
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• pp.1-12
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• 2008

Background and Objectives: Sinusitis is a common disease in the otorhinolaryngology field. It is inflammatory change of the mucous membrane which surrounds the sinus. The aim of this study was to investigate the anti-inflammatory effects of the Taklisodok-eum (TSE) extract on the mouse model with acute sinusitis induced by S. pneumoniae. Methods: Thirty six-week-old male BALB/c mice were divided into three groups: the normal group, the group inoculated with S. pneumoniae which caused allergic rhinitis (control group), and the group treated with the TSE extract after it was treated the same as the control group (sample group). Results: $NF-{\kappa}B$ activation was suppressed, and iNOS & COX-2 production were inhibited by TSE in acute sinusitis. Apoptosis was increased by TSE in acute sinusitis. The number of eosinophils in the sample group noticeably decreased when compared to the control group. In the general morphologic change, the increase of damaged respiratory ciliated epithelia & eosinophils' infiltration was lessin the sample group. Goblet cells were maintained in the sample group. MMP-9, HSP-70 and BrdU decreased in the sample group. Apocrine secretion decreased in the sample group. Conclusion: The findings in this study show that TSE reduces acute sinusitis through its anti-inflammatory effects, such as the inhibition of $NF-{\kappa}B$ activity.

• Journal of Life Science
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• v.11 no.2
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• pp.126-132
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• 2001

Effect of Quartz porphyty(QP) on functional and morphological changes of the liver and kidney was studied in male common finch and white java sparrow fed with the basal diet(Control group) or experimental diet containing 3.0% QP(QP group) for 14 days. There was not significantly different morphological change of the liver upon light microscopic examination in common finch and white java sparrow between control group and QP group. Morphological change of renal tissue upon light microscopic examination in common finch and white java sparrow was not also significantly different between control group and QP group. The concentrations of serum creatinine, blood urea nitrogen, and nric acid as renal functional parameters of common finch and white java sparrow were not significantly different in the both groups. The activity of glutamic oxaloacetic transaminase(GOT) as hepatic functional parameter in common finch was significantly higher in the QP group($\rho$<0.05), whereas the activity of glutamic pyruvic transaminase(GPT) as hepatic functional parameter in common finch was not significantly different in the both groups. The activities of GOP and GPT in white java sparrow were not significantly different in the both groups. The morphologic findings and functional parameters of the liver and kidney observed in common finch and white java sparrow fed with 3.0% QP diet showed evidence of slightly liver damage accompanied with increased release of enzyme and fatty change of the hepatocytes in common finch, suggested that the tissues in some animals can be damaged by feeding a diet supplemented with 3.0% QP.