• Progress in Medical Physics
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• v.13 no.4
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• pp.202-208
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• 2002

The purpose of this study is to evaluate the monitor unit obtained from various methods for the treatment of superficial cancers using electron beams. Thirty-three breast cancer patients who were treated in our institution with 6, 9, and 12 MeV electron beams, were selected for this study. For each patient, irregularly shaped treatment blocks were drawn on simulation film and constructed. Using the irregular blocks, monitor units to deliver 100 cGy to the dose maximum (dmax) were calculated from measurement and three-dimensional radiation treatment planning (3D RTP) system (PINNACLE 6.0, ADAC Laboratories, Milpitas CA) Measurements were made in solid water phantom with plane parallel (PP) chamber (Roos, OTW Germany) at 100 cm source-to surface distances. CT data was used to investigate the effect of heterogeneity. Monitor units were calculated by overriding CT values with 1 g/㎤ and in the presence of heterogeneity. The monitor unit values obtained by the above methods were compared. The dose, obtained from measurement in solid water phantom was higher than that of RTP values for irregularly shaped blocks. The maximum differences between monitor unit calculated in flat water phantom at gantry zero position were 4% for 6 MeV and 2% for 9 and 12 MeV electrons. When CT data was used at a various gantry angle the agreement between the TPS data with and without density correction was within 3% for all energies. These results indicate that there are no significant difference in terms of monitor unit when density is corrected for the treatment of breast cancer patients with electrons.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.593-599
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• 2010

A seven-year-old, castrated male Basset hound weighing 21.1 kg was presented for investigation of anorexia, lethargy, weight loss, melena and vomiting for 4 months. In laboratory findings, microcytic hypochromic anemia was identified, and other results were within a normal reference range. On the plain radiographs, soft tissue opacity was increased in the descending duodenal region; and on the contrast radiographs, ulcerative changes were identified in the entire segment of descending duodenum. Ultrasonographic findings included increased duodenal wall thickness and duodenal wall layering was lost. Endoscopy revealed irregular mucosal surface and luminal narrowing of the descending duodenum. There was concentrically thickened descending duodenum on the computed tomography. And the wall of the descending duodenum showed heterogenous enhancement after contrast agent injection. On histopathological findings, both chronic inflammation with mucosal proliferation and neoplastic changes with multiple small glandslike structures invading into the submucosa were identified. Based on these findings, presented case was diagnosed as an annular form duodenal adenocarcinoma. After 13 months of supportive medical treatment, the patient was expired. The purpose of this case report was to describe the duodenal adenocarcinoma in a dog.

• Journal of Life Science
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• v.23 no.3
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• pp.341-346
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• 2013

The disappearance of seaweed flora in some rocky areas, which is known as algal whitening, barren ground, coralline flats, or deforested areas, is associated with some species of coralline algae. To determine the biological characteristics of a representative species of crustose coralline alga, the 18S rDNA gene was sequenced to identify the genus Lithophyllum. According to its morphological and distributional characteristics, it was deduced to be L. yessoense. Viability was measured using triphenyl tetrazolium chloride and showed high viability from December to February. Culture conditions of $16^{\circ}C$, a 16 hr light, 8 hr dark cycle, and 30 ${\mu}E/m^2/s$ light intensity were optimal for maintaining the viability of the alga for up to five days. Included in the fatty acids was 9.7% ${\omega}$-3 eicosapentaenoic acid. An electron microscopy scan of the surface structure revealed round craters about 3.6 ${\mu}m$ in diameter, which were covered with rough, irregular, and angular polygon-shaped structures about 1.0 to 3.7 ${\mu}m$ in size. Based on the composition and structure found in our study, biomimetic coralline alga might become an environmentally friendly antifouling material against the attachment of soft foulants.

• Clean Technology
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• v.18 no.1
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• pp.76-82
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• 2012

The paper includes utlization of zeolite as potential adsorbent to remove a hazardous malachite green from waste water. The adsorption studies were carried out at 298, 308 and 318 K and effects of temperature, contact time, initial concentration on the adsorption were measured. On the basis of adsorption data Langmuir and Freundlich adsorption isotherm model were also confirmed. The equilibrium process was described well by Freundlich isotherm model, showing a selective adsorption by irregular energy of zeolite surface. From determined isotherm constants, zeolite could be employed as effective treatment for removal of malachite green. From kinetic experiments, the adsorption process followed the pseudo second order model, and the adsorption rate constant ($k_2$) decreased with increasing initial concentration of malachite green. Thermodynamic parameters like activation energy, change of free energy, enthalpy, and entropy were also calculated to predict the nature adsorption. The activation energy calculated from Arrhenius equation indicated that the adsorption of malachite green on the zeolite was physical process. The negative free energy change (${\Delta}G^{\circ}$ =-6.47~-9.07 kJ/mol) and the positive enthalpy change (${\Delta}H^{\circ}$ = +32.414 kJ/mol) indicated the spontaneous and endothermic nature of the adsorption in the temperature range 298~318 K.

• Geophysics and Geophysical Exploration
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• v.19 no.3
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• pp.121-130
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• 2016

Several factors are discussed that should be considered in measuring thermal conductivity of rock cores with a PEDB (potable electronic divided bar) system, which is relatively accurate and easy to operate, and can measure the thermal conductivity of rock cores for various diameters. Then the system is applied to measure thermal conductivity of 70 rock cores from Ulleung Island. Air temperature affects most on the thermal conductivity measurements, so that it is very important to minimize the temperature change during the measurement. Other factors such as the temperature of heat source, averaging time window on the thermal conductivity measurements do not affect much compared to air temperature. Slightly higher thermal conductivity is measured when using the thermal contact paste between the sample and heat source or heat sink. Especially, rock cores with irregular surface showed bigger difference. Repeatability showed less than ${\pm}0.3%$ for standard samples and less than ${\pm}4%$ for rock samples, respectively, when the room temperature changes within $1^{\circ}C$ during the measurements. Thermal conductivity of the rock cores from Ulleung Island roughly increases as depth increases but does not show any dependency on the rock types.

• Journal of the Korean Magnetics Society
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• v.16 no.2
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• pp.140-143
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• 2006

Single crystalline $CoFe_2O_4$ thin films on (100) MgO substrates were fabricated using a rf magnetron sputtering method. The deposited films were investigated for their crystallization by X-ray diffraction, Rutherford back-scattering spectroscopy and field emission scanning electron microscopy. When a cobalt ferrite film was deposited at the substrate temperature of $600^{\circ}C$, squared grains of about 200 nm were uniformly distributed in the film. However, the grains became irregular and their sizes also varied from 30 to 150 nm when the substrate temperature was $700^{\circ}C$. Hysteresis loops of a film deposited at $600^{\circ}C$ showed that the magnetically easy axis of the film was perpendicular to the substrate surface. Except for the squareness ratio, magnetic properties of the cobalt ferrite films grown by the present rf sputtering method were as good as those of the films prepared by a laser ablation method: The in-plane and perpendicular coercivities were 283 and 6800 Oe, respectively. As the thickness of the deposited film increased twice, the saturation magnetization became double but the coercivity remained unchanged. However, deposition of the Co ferrite films with a higher rf powder decreased the squareness ratio and the perpendicular coercivity of the films.

• Journal of Energy Engineering
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• v.24 no.1
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• pp.114-122
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• 2015

In the high convective gas flow condition, irregular shaped water waves from which droplet entrainment occurs are generated under horizontally stratified two-phase flow condition. KAERI proposed a new mechanistic droplet entrainment model based on the momentum balance equation consisting of the shear stress, surface tension, and gravity forces. However, this model requires correlation or experimental data of several physical parameters related to the wave characteristics. In the present study, we tried to measure the physical parameters such as wave slope, wave hypotenuse length, wave velocity, wave frequency, and wavelength experimentally. For this, an experiment was conducted in the horizontal rectangular channel of which width, height, and length are, respectively, 40 mm, 50 mm, and 4.2 m. In the present test, the working fluids are chosen as air and water. The PIV technique was applied not only to obtain images for phase interface waves but also to measure the velocity field of the water flow. Additionally, we developed the parallel wire conductance probe for the confirmation of wave height from PIV image. Finally, we measured the physical parameters to be used in the validation of new droplet entrainment model.

• Applied Microscopy
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• v.15 no.2
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• pp.111-129
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• 1985

The morphology and histology of the gastrointestinal mucosa of the mole, Talpa micrura coreana (Thomas), were studied using light and scanning electron microscopes. Tissue specimens were taken from body and pyloric portions of the stomach, and from the initial, proximal, middle, distal and terminal portions of the intestine. For light microscopy, tissue blocks were fixed in 10% buffered neutral formalin, embedded in paraffin wax, and sectioned at a thickness of $5{\mu}m$. These sections were stained with hematoxylin-eosin. For scanning electron microscopy, tissue blocks were fixed in 1% glutaraldehyde-1.5% paraformaldehyde, and postfixed in 1% osmium tetroxide, dehydrated in graded alcohol, transferred to isoamylacetate and dried by the critical point drier(Polaron E 3000). Subsequently, specimens were coated with gold and observed with a JSM-35C scanning electron microscope. The results were as follows: The mucous membrane of the body portion of the stomach had numerous irregular folds and the pyloric mucosa formed the strawberry-shaped folds, and general histological structures of each portion were similar to those of man. The intestine could not be differentiated macroscopically and microscopically into small and large intestines. There was no cecum, appendix, taenia coli, haustra coli or appendices epiploicae. In the initial portion (4 mm long), conical or tongue-shaped villi with the height of $143.3{\pm}10.7{\mu}m$ were present, and large mucous glands were seen in the submucosa. In the proximal, middle and distal portions, wavy folds composed of the epithelium and lamina propria were densely and transversely arranged, and their heights were $440.4{\pm}45.5{\mu}m,\;454.4{\pm}19.9{\mu}m\;and\;205.2{\pm}33.5{\mu}m$, respectively. The mucosa of the terminal portion (3 cm long) formed several longitudinal folds, and the intestinal glands were directly opened on the smooth surface of the folds. Aggregated lymphoid follicles were observed in the major portions of the intestine except the initial and terminal portions. There was no circular or semilunar fold throughout the intestine.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.30 no.4
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• pp.166-179
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• 2018

This study aims at numerically investigating the water-surface characteristics such as wave height distribution depending on the current direction around the three-dimensional permeable submerged breakwaters in wave-current coexisting field which has not been considered in detail so far. In addition, the characteristics of the velocity field including the average flow velocity, longshore current and turbulent kinetic energy, which act as the main external forces of formation of salient, are also examined. For numerical analysis, olaFlow which is open source code of CFD was used and the numerical tests included different types of target waves, both regular waves and irregular waves. Numerical results indicated that wave height variation with wave following or opposing a current behind the submerged breakwater is closely related to turbulent kinetic energy. Furthermore, it was found that weaker longshore currents are formed under wave-current coexisting field compared to the non-current conditions, and transport flow is attenuated. As a result, it was possible to understand the influence of current existence and direction (following and opposing) on the formation of the salient formed behind the submerged breakwaters.

• Parasites, Hosts and Diseases
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• v.31 no.4
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• pp.301-314
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• 1993

An electron microscopic study was performed to observe the ultrastructure of the tegument of U seoulensis. The outer surface of the tegument was covered with a tnlaminated plasma membrane. The electron-dense cytoplasmic layer was $2.5{\;}\mu\textrm{m}$ wide In the anterior portion and contained numerous vacuoles, mitochondriae and granular materials in its matrix. The basement layer was 330 nm wade or so, and Its numerous extensions protruded into the cytoplasmic layer. The sensory organ was composed of a small vesicle of $1.7{\;}{\times}{\;}1.1{\;}\mu\textrm{m}$ in dimensions, which possessed a cilium of $1.2{\;}{\times}{\;}0.19{\;}\mu\textrm{m}$ in size. The pharynx was composed of the epithelial layer of about $0.5{\;}\mu\textrm{m}$ wide, well developed muscle layer and basement layer. The tegument of the oral sucker was composed of a cytoplasmic layer of $0.4-0.5{\;}\mu\textrm{m}$ width, a narrow basement layer, a well developed muscle layer and tegumental cells. Some kinds of secretory granules that seemed to be originated from the cells of the oral sucker were observed In the parenchymal portions of the adjacent cells. The tribocytic organ consisted of numerous microvilli. The microvilli were 5 nm wide and heptalaminated. Two types of secretory granules originated from the gland cells of tribocytic organ were observed In the tegument and parenchyme. The tegumental cells were irregular in shape, and of which nuclei were multifarious.