• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.176-183
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• 2012

This study was carried out to develop ferns as the natural antioxidant materials by graduating and extracting fronds of $Dryopteris$ $crassirhizoma$, $Dryopteris$ $nipponensis$, and $Polystichum$ $lepidocaulon$, which belong to Dryopteridaceae, using solvent, and analyzing the antioxidant effect of each fraction. The n-butanol fraction of $D.$ $crassirhizoma$ (550.0 $mg{\cdot}g^{-1}$), the ethyl acetate fraction of $D.$ $nipponensis$ (374.8 $mg{\cdot}g^{-1}$), and the n-butanol fraction of $P.$ $lepidocaulon$ (781.8 $mg{\cdot}g^{-1}$) showed relatively higher total contents of polyphenol. The chloroform fraction of $D.$ $crassirhizoma$ (72.9 $mg{\cdot}g^{-1}$), and the n-hexane fraction of $D.$ $nipponensis$ (72.9 $mg{\cdot}g^{-1}$) and $P.$ $lepidocaulon$ (154.5 $mg{\cdot}g^{-1}$) contained relatively higher total contents of flavonoids. DPPH radical scavenging activity was most excellent in the n-butanol fraction of $D.$ $crassirhizoma$ ($RC_{50}=0.02mg{\cdot}mL^{-1}$) and $P.$ $lepidocaulon$ ($RC_{50}=0.04mg{\cdot}mL^{-1}$), and the water fractions of $D.$ $nipponensis$ ($RC_{50}=0.01mg{\cdot}mL^{-1}$). ABTS radical scavenging activity was potent in the n-hexane and n-butanol fractions of $D.$ $crassirhizoma$ (each $RC_{50}=0.02mg{\cdot}mL^{-1}$), the ethyl acetate fraction of $D.$ $nipponensis$ ($RC_{50}=0.03mg{\cdot}mL^{-1}$), and the n-butanol fraction of $P.$ $lepidocaulon$ ($RC_{50}=0.06mg{\cdot}mL^{-1}$). There was the large amount of total polyphenol content in the n-butanol fraction of $D.$ $crassirhizoma$ and $P.$ $lepidocaulon$, and their radical scavenging activities were potent. Therefore, it was thought that biologically active substances of each fraction layer are required to be analyzed and used.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.12-21
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• 2003

In this study, we evaluated effects of three anastomotic techniques of small intestine on adhesions in the dog. Twenty six healthy mixed dogs were randomly assigned to three groups. Group I(n = 8) was sutured with a simple continuous suture, group II(n = 7) was sutured with a simple interrupted approximating suture and group III(n = 11) was sutured with a single layer continuous Connell suture. On completion of any intestinal anastomosis, a pedicle of greater omentum was wrapped around the suture line in all experimental dogs. One percent sodium carboxymeth-ylcellulose (5ml/kg) was administrated into the abdomen by feeding tube prior to closing the last part of peritoneum in all dogs. Postoperative adhesions were evaluated at 14th day after operation. The adhesions consisted primarily in two dogs in group I, three dogs in group II and group III. There were adhesions between intestinal serosal surfaces in eight dogs in all groups, but there were no intestinal serosa-visceral peritoneum adhesion and intestinal serosa-mesentery adhesion. Mean adhesion scores were less than score 2 in all groups. Between anastomotic site and omental graft, there were 13.13$\pm$4.97 mm (mean$\pm$S.D.) adhesion formation in group I and 17.29$\pm$4.68 mm in group II and 14.64$\pm$3.80mm in group III. A simple continuous suture resulted in the least adhesion formation and a simple interrupted approximating suture resulted in the greatest adhesion formation among the groups. However, there were no significant differences among three suture techniques in the severity of adhesions. Intestinal intussusception only encountered in one dog during the 14 days, the dog operated and survived. Daily monitoring of temperature, activity, appetite, defecation and micturition were done. All of those vital signs were within normal values and there were no obvious differences among the groups. In conclusion, even though there were no significant differences among three groups, a simple continous suture pattern is recommended to prevent adhesions when operating intestinal anastomosis in dogs.

• Journal of the Korean Applied Science and Technology
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• v.37 no.3
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• pp.484-495
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• 2020

This study is a mixed surfactant (MimicLipid-MSM1000) that forms the same structure as that of the stratum corneum, sucrose distearate, polyglyceryl-2 dioleate, fermented squalane, ergosterol, 10-hydroxystearic acid, mixture consisting of was synthesized. When using 2~5 wt% of this mixed surfactant, it was possible to make an artificial skin mimetic that forms a multi-layer lamellar structure of 5~30 layers. An emulsion was prepared using this mixed surfactant, and a multi-layered lamellar phase was formed and analyzed mechanically. The appearance of this surfactant was a light brown hard wax, the hydrophilic lipophilic balance (HLB) was 12.53, the critical parameter value was 0.987, and the acid value was 0.13. Stability according to pH change was also stable in acidic (3.8), neutral (7.2) and alkaline (10.8). The particle size of the liquid crystal was found to be the most stable maltese cross lamellar crystalline droplet at 5~25mm. The size of the emulsified particles according to the change in the speed of the homo agitator is 2500 rpm (17.9mm±2.6mm), 3500rpm (12.5mm±2.1mm), 4500rpm (6.2mm±1.8mm) particles were formed. Liquid crystal forming particles were observed through a polarization microscope, and the formation structure of the liquid crystal was precisely analyzed with a scanning electron microscope (cryo-SEM). As an application field, it is expected that it will be widely applicable to the development of various prescriptions, such as various skin care cosmetics, makeup care cosmetics, and scalp protection cosmetics, by using a skin-mimicking surfactant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.222-224
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• 1975

Three strains of common carp, i. e. , Israeli carp, red-and-white, and golden strains, were stocked in the same pond, and their growth rates were compared with following results: From August 12 to November 21 in 1975, fingerlings of the three strains of common carp, Cyprinus carpo, each weighing about 0.5 g with total length of 2 to 3 cm, were stocked. The pond had an area of $316m^2$ with a mean water depth of 55cm, and the bottom was covered with a 20 to 30 cm thick layer of silt containing a considerable amount of decaying organic materials. Feed given was prepared with equal amounts of fish meal and polished barley, of which, in addition, $10\%$ green grass and $1\%$ table salt were mixed together when prepared into paste feed using a chopper after boiling the barley. Total protein content of the feed was $34.9\%$ in dry state with $5\%$ moisture content. Total feed given was 30.08 kg calculated in dry state to produce 20.588 kg of the common carp fingerlings, thus the feed coefficient being 1.51. By strains, the harvested Israeli carp ranged 98 to 311g each with a mean weight of $172.69g(100\%)$, red-and-white strain 15 to 318g with mean of $104.1g(60.3\%)$, and the golden strain 30 to 268g with mean of $128.7g(74.6\%)$. During the rearing season mean water temperature was $23.9^{\circ}C$ and the assumed main growth period with the water temperature above $15^{\circ}C$ was, upto the end of October, for 80 days with a mean water temperature of $23.9^{\circ}C$. Taking this main growth period as the basis for growth rate analysis, the mean daily increments, expressed as the attained body weight in times of the starting weight, become 1.075786 times (or the Israeli strain, 1.06901 times for the red-and-white strain, and 1.07185 times for the golden strain.

• Restorative Dentistry and Endodontics
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• v.33 no.3
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• pp.246-257
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• 2008

The purpose of this study was to investigate the influence of various occlusal loading sites and directions on the stress distribution of the cervical composite resin restorations of maxillary second premolar, using 3 dimensional (3D) finite element (FE) analysis. Extracted maxillary second premolar was scanned serially with Micro-CT (SkyScan1072; SkyScan, Aartselaar, Belgium). The 3D images were processed by 3D-DOCTOR (Able Software Co., Lexington, MA, USA). HyperMesh (Altair Engineering, Inc., Troy, USA) and ANSYS (Swanson Analysis Systems, Inc., Houston, USA) was used to mesh and analyze 3D FE model. Notch shaped cavity was filled with hybrid (Z100, 3M Dental Products, St. Paul, MN, USA) or flowable resin (Tetric Flow, Vivadent Ets., FL-9494-Schaan, Liechtenstein) and each restoration was simulated with adhesive layer thickness ($40{\mu}m$). A static load of 200 N was applied on the three points of the buccal incline of the palatal cusp and oriented in $20^{\circ}$ increments, from vertical (long axis of the tooth) to oblique $40^{\circ}$ direction towards the buccal. The maximum principal stresses in the occlusal and cervical cavosurface margin and vertical section of buccal surfaces of notch-shaped class V cavity were analyzed using ANSYS. As the angle of loading direction increased, tensile stress increased. Loading site had little effect on it. Under same loading condition, Tetric Flow showed relatively lower stress than Z100 overall, except both point angles. Loading direction and the elastic modulus of restorative material seem to be important factor on the cervical restoration.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.1
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• pp.61-66
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• 2012

Chemical Mechanical Planarization (CMP) is a polishing process used in the microelectronic fabrication industries to achieve a globally planar wafer surface for the manufacturing of integrated circuits. Pad conditioning plays an important role in the CMP process to maintain a material removal rate (MRR) and its uniformity. For metal CMP process, highly acidic slurry containing strong oxidizer is being used. It would affect the conditioner surface which normally made of metal such as Nickel and its alloy. If conditioner surface is corroded, diamonds on the conditioner surface would be fallen out from the surface. Because of this phenomenon, not only life time of conditioners is decreased, but also more scratches are generated. To protect the conditioners from corrosion, thin organic film deposition on the metal surface is suggested without requiring current conditioner manufacturing process. To prepare the anti-corrosion film on metal conditioner surface, vapor SAM (self-assembled monolayer) and FC (Fluorocarbon) -CVD (SRN-504, Sorona, Korea) films were prepared on both nickel and nickel alloy surfaces. Vapor SAM method was used for SAM deposition using both Dodecanethiol (DT) and Perfluoroctyltrichloro silane (FOTS). FC films were prepared in different thickness of 10 nm, 50 nm and 100 nm on conditioner surfaces. Electrochemical analysis such as potentiodynamic polarization and impedance, and contact angle measurements were carried out to evaluate the coating characteristics. Impedance data was analyzed by an electrical equivalent circuit model. The observed contact angle is higher than 90o after thin film deposition, which confirms that the coatings deposited on the surfaces are densely packed. The results of potentiodynamic polarization and the impedance show that modified surfaces have better performance than bare metal surfaces which could be applied to increase the life time and reliability of conditioner during W CMP.

• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.471-484
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• 2009

This study was carried out to classify vegetation structure on the deciduous forest at Namdeogyu area in Deogyusan National Park from May 2007 to September 2008 using the gradient analyses and phytosociological method. The vegetation was classified into Quercus mongolica community(Typical subcommunity, Rhododendron sehlippenbaehii-Q. mongolica subcommunity, Carex lanceolata-Q. mongolica subcommunity), Q. Serrata community(Typical subcommunity, Q. variabilis -Q. serrata subcommunity, Carpinus laxiflora - Q. serrata subcommunity), C. laxiflora community, Fraxinus mandshurica community and Corn us controversa community. Ecological characteristics such as species composition, layer structure, vegetation ratio, and the distribution of individual trees by DBH(diameter at breast height) were significantly different among communities. The order of important value of the forest community with DBH 2cm above plants was Q. mongolica(67.8), F. mandshurica(44.8), Q. serrata(27.5), Acer pseudo-sieboldianum(17.0), C. controversa(l5.9), F. sieboldiana(l1.5), R. schlippenbachii(11.0), C. cordata(11.0), Styrax obassia(10.9), Magnolia sieboldii(10.4) and C. laxiflora(9.8). Distribution of DBH of Q. mongolica had a formality distribution, suggesting a continuous domination of these species over the other species for the time being. In contrast, F. mandshurica appeared limited to the valley of the sheet and a higher frequency of young individuals, suggesting a continuous domination of these species the development of a climax forest terrain. Q. serrata had a higher frequency of young individuals and middle individuals, suggesting a continuous domination of these species over the other species for the time being in contrast. This study examined the correlation between each community and the environment according to DCCA ordination. The Q. mongolica community predominated in the highest elevation habitats which had many C.E.C and T-N. F. mandshurica community predominated in the highest elevation habitats which had many Moisture and EX-Cation. The Q. serrata community and C. laxiflora community mainly occurred in the low elevation habitats which had few C.E.C and T-N. The C. controversa community appeared on the park in the middle habitats.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.1
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• pp.31-37
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• 2000

This study was designed to identify the ultrastructural changes of mouse endometrium during peri-implantation period and obtain the fundamental information for the establishment of 3-dimensional culture system of mouse endometrial cells in vitro. The used female ICR mice ($6{\sim}8$ wks) were conducted on pregnant. The biopsies were obtained from whole uterus at cycle day 1 (D1) and day 5 (D5) after hCG injection and mating. The biopsies materials were fixed 2.5% glutaraldehyde and 1% osmium tetroxide. Subsequently, for observation using light and transmission electron microscopy (LM and TEM), they were dehydrated and embedded in Epon and the embedded biopsies were sectioned and stained. For scanning electron microscopy (SEM), the fixed specimens were dehydrated, dried and coated with gold. 1) For LM, the biopsied materials at D5 (late secretory phase) were appeared the extended stromal layer by increased connective tissues and the fully developed endometrial glands and vessels compared with D1 (early secretory phase). 2) For TEM, the mouse endometrium was consisted of 3-layers, a simple polarized columnar epithelial cells, basement membrane and stromal cells. At D5, the distribution of microvilli, endoplasmic reticulum, Golgi body, lipid and glycogen deposits, secretory granules and surface area of basement membrane were increased. 3) For SEM, the degree of folding and microvilli of surface of mouse epithelial cells was became more and more according to the process of secretory phase, and at D5, implantation time of mouse, the appearance of pinopodes as a specific marker of uterine receptivity was found. The uterine pinopodes of mouse were found in narrow sites at the luminal surface, irregularity and appeared the different stages in the same sample. Therefore, these results indicated that the mouse endometrium was experienced dramatic morphological changes during peri-implantation period.

• Journal of the Korean Electrochemical Society
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• v.1 no.1
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• pp.1-7
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• 1998

For the purpose of finding new cathode materials for medium-temperature $(700\~800^{\circ}C)$ solid oxide fuel cells, $Gd_{0.8}Ca_{0.2}Co_{1-x}Fe_xO_3,\;(x=0.0\~0.5)$ are prepared, and their thermal stability and conductivity characteristics are investigated. Also, the cathodic activities are measured after the cathode layer being attached on CGO (cerium-gadolinium oxide) electrolyte disk. The X-ray analyses indicate that the materials prepared by calcining the citrate-gels at $800^{\circ}C$ have the orthorhombic perovskite structure without discernible impurities. The thermal stability of the undoped Co perovskite is so poor that it is decomposed to the individual binary oxide even at $1300^{\circ}C$. But the partially Fe-doped cobaltates exhibit a better thermal stability to retain their structural integrity up to $1400^{\circ}C$. The observation whereby both the undoped and Fe-doped cobaltates melt at ca. $1300^{\circ}C$ leads us to perform the electrode adhesion at <$1300^{\circ}C$. The cathodic activity of $Gd_{0.8}Ca_{0.2}Co_{1-x}Fe_xO_3,\;(x=0.0\~0.5)$, electrodes is superior to $La_{0.9}Sr_{0.1}MnO_3$, among the samples of $x=0.0\~0.5$, the x=0.2 cathode shows the best activity for the oxygen reduction reaction. It is likely that the Fe-doping provides a better thermal stability to the materials but in turn imparts an inferior cathodic activity, such that the optimum trade-off is made at x=0.2 between the two factors. The total electrical conductivity and ion conductivity of $Gd_{0.8}Ca_{0.2}Co_{1-x}Fe_xO_3$, are measured to be 51 S/cm and $6.0\times10^{-4}S/cm\;at\;800^{\circ}C$, respectively. The conductivity values illustrate that the materials are a mixed conductor and the reaction sites can be expanded to the overall electrode surface, thereby providing a better cathodic activity than $La_{0.9}Sr_{0.1}MnO_3$.

• Journal of the Korean Electrochemical Society
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• v.18 no.3
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• pp.121-129
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• 2015

The platinum anode for the electrolytic reduction process is generally surrounded by a nonporous ceramic shroud with an open bottom to offer a path for $O_2$ gas produced on the anode surface and prevent the corrosion of the electrolytic reducer. However, the $O^{2-}$ ions generated from the cathode are transported only in a limited fashion through the open bottom of the anode shroud because the nonporous shroud hinders the transport of the $O^{2-}$ ions to the anode surface, which leads to a decrease in the current density and an increase in the operation time of the process. In the present study, we demonstrate the electrolytic reduction of 1 kg-uranium oxide ($UO_2$) using the porous shroud to investigate its long-term stability. The $UO_2$ with the size of 1~4mm and the density of $10.30{\sim}10.41g/cm^3$ was used for the cathode. The platinum and 5-layer STS mesh were used for the anode and its shroud, respectively. After the termination of the electrolytic reduction run in 1.5 wt.% $Li_2O-LiCl$ molten salt, it was revealed that the U metal was successfully converted from the $UO_2$ and the anode and its shroud were used without any significant damage.