• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.1
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• pp.15-22
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• 1994

The formation of carbonyl group was dominant to other functional groups. Concentrations of both carboxyl and peroxide groups were found to rapidly reach low steady state values that increased slightly with increa-sing temperature and relatice humidity. Since the deg-radation of cellulose samples was in the initial stage and the conversion of glycosidic bonds and hydroxyl groups were very small, it was found that changes in the physical and chemical properties could be fitted to a first-order reaction model.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.58.2-58.2
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• 2010

L1251B, which was revealed as a small group of protostars by the Spitzer Space Telescope (SST), presents a great site of studying chemical evolution in gas and ice as well as various dynamical processes associated with star formation (infall, rotation, and outflow). We have mapped L1251B with the Infrared Spectrograph (IRS) aboard the SST to study the chemical distribution in the phases of gas and ice and the dynamical feature related to shock in the region. Various atomic lines and the $H_2$ pure rotational lines, which trace different shock velocities, were detected. In addition, the distribution of the water and $CO_2$ ices hints variety of the ice desorption mechanism in L1251B.

• Journal of the Korean Society for Heat Treatment
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• v.27 no.4
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• pp.185-190
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• 2014

The influences of small amount of Sn addition on microstructure and creep resistance of AZ91-0.4%Ca alloy have been investigated. The microstructure of the AZ91-0.4%Ca alloy was characterized by ${\alpha}$-(Mg) dendrite cells surrounded by eutectic ${\beta}(Mg_{17}Al_{12})$ and $Al_2Ca$ phases. The 0.5%Sn addition resulted in the formation of rod-shaped CaMgSn particles with the extinction of $Al_2Ca$. The Sn-containing alloy exhibited better creep resistance below $175^{\circ}C$, but the tendency was reversed above $200^{\circ}C$. The reason was discussed in relation to the change in thermal stability of ${\beta}$ phase in response to the Sn addition.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.10 no.1
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• pp.49-74
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• 1984

Rheology of gels prepared with stearyl dimethyl benzyl ammonium hectorite (SDBAH) and various polar additives in n-butyl acetate was investigated by measuring the viscosity and rheogram. Including generally recognized polar additives, additional studies on the rheogram and viscosity were made with ether-type methyl cellosolve and carbitol, with dimethyl sulfoxide (DMSO) having sulfonyl group, and furthermore with above-mentioned polar additives containing small quantity of water, It was observed that molecular size, dipole moments and dielectric constants of polar additives had a great influence on viscosity increase and rheology of SDBAH gel, and the increase of SDBAH interlayer spacing was important factor in gel formation and viscosity change. It was also shown that thixotropy effect was increased with the increase of polar additive concentration, finally changed to rheopexy from thixotropy as the concentration of polar additives was increased more than about 40% of SDBAH weight. In addition thixotropy changed to rheopexy as the increase of shear rate. It was further found that the aqueous solutions of polar additives (water content, 5-25%) had more effects on rheology than additives without water, and particularly 95clo DMSO solution was the most effective. And the optimum concentration of polar additives showing maximum viscosity in the same SDBAH concentration system was examined.

• The Journal of the Korean dental association
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• v.15 no.12
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• pp.957-962
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• 1977

The author has observed the tissue reaction of the absolute alcohol infection of rat oral mucosa. 0.5ml absolute alcohol was injected subcutaneously on the mucobuccal fold of rat. And the rats were sacrifieced at intervals of one day, 3rd, 1 week, 2 week and 4 week after alcohol injection. The microscopic tissue sections were made and stained with hematoxylin and eosin. The results were are as follows; 1. Degeneration and shrinkage of fibroblasts and coagulative necrosis were observed one day to and three day after alcohol injection. 2. Although coagulative necrosis and tissue degeneration occurred, the inflammatory infiltration was not prominent especially there were scarcely any polymorphonuclear leukocytes in that field. 3. Granulation tissue with moderate small round cell infiltration were replaced the necrotic area at one week after injection and the fibroblast proliferate into the granulation tissue at two week group. 4. At four week after injection, the damaged area recovered by fibroblastic proliferation and collage formation, but there were

• Journal of Korea Foundry Society
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• v.33 no.3
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• pp.127-133
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• 2013

The influences of a small amount of CaO addition on the microstructure and corrosion behavior of AZ81 casting alloy have been investigated by means of optical microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, immersion and electrochemical tests. The added CaO led to the refinement of ${\alpha}$-Mg grains and the decrease in ${\beta}$ precipitate content by the formation of an $Al_2Ca$ phase. The AZ81-CaO alloy had a better corrosion resistance than the AZ81 alloy. The microstructural characterization on the corroded surface revealed that the enhanced corrosion resistance of the CaO-containing alloy may well be ascribed to the increased barrier effect of precipitates formed more continuously along the grain boundaries and the incorporation of Al and Ca elements into the corrosion film, by which it became more protective.

• Journal of Oral Medicine and Pain
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• v.7 no.1
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• pp.5-26
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• 1982

In order to study the effects of traimcinolone acetonide on the wound healing of tongue, eight two healthy albino rats were asesthetized with pentothal. The wound, approximately 1mm in depth and 2mm in diameter, was created on the midlateral aspect of tongue with the tip of small rongeur fourcep. Forty one animals were employed in one of the following groups:(I) Control group: Received 0.5ml/100gm B.W. of saline suspension intralesionally at weekly interval until sacrificed.(II) Experimental group: Received $100\mu\textrm{g}/100gm$ B.W. of trimacinolone acet- onide suspension intralesionally at weekly interval until sacrificed. Biopsy specimens of wounds were taken at 6,18,24 hours, 2,3,5,7,14 and 28 days after wounding. The specimens were sectioned, and observed with light microscope and electron microscope. The results were as follows : 1. In the triamcinolone acetonide treated wound, the epithelial and fibroblastic regeneration were dealayed when compared with controls. 2. After triamcinolone acetonide treated, edema was decreased at the early stage of wound healing. 3. In the triamcinolone acetonide treated wound, the fibroblasts exhibited fine morphological changes and reduction of collagen formation. It seems that triamcinolone acetonide inhibits fibroblast function.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.71-75
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• 2016

Pancreatic cancer is a leading cause of fatality worldwide. Several population studies have been conducted on genetic diagnosis of pancreatic cancer but the results from epidemiologic studies are very limited. CYP17A gene has a role in disease formation but its influence on pancreatic cancer is unclear. A polymorphism in the 5'UTR promoter region of CYP17A1-34T/C (A1/A2) has been associated with multiple cancers. The aim of the current study was to assess associations of this polymorphism and socio-demographic risk factors with pancreatic cancer. A total of 255 and 320 controls were enrolled in the study, and were genetically analyzed through PCR-RFLP. Statistical analysis was conducted with observed genotype frequencies and odds ratios (ORs) and 95% CIs were estimated using unconditional logistic regression. The impact of socio-demographic factors was accessed through Kaplen-Meir analysis. According to our results, the A2/A2 genotype was significantly associated with pancreatic cancer (OR=2.1, 95%CI = 1.3-3.5). Gender female (OR=2.6, 95%CI=1.8-3.7), age group 80s/80+ years (OR=2.2, 95% CI=1.2-4), smoking both former (OR=4.6, 95% CIs=2.5-8.8) and current (OR=3.6, 95% CI=2-6.7), and family history (OR=7.1; 95%CI = 4.6-11.4) were also found associated with increased risk. Current study suggests that along with established risk factors for pancreatic cancer CYP17A1-34T/C may play a role. However, on the basis of small sample size the argument cannot be fully endorsed and larger scale studies are recommended.

• Journal of Veterinary Clinics
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• v.18 no.3
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• pp.243-248
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• 2001

Radiographic findings of degenerative joint disease (DJD) in the coxofemoral joints were studied in 108 dogs referred to Veterinary Medical Teaching Hospital, College of Veterinary Medicine, Seoul National University. Radiographic findings were identified with a extended ventrodorsal projection. Clinical signs such as pain in the affected joint, exercise intolerance, lameness, crepitation on flexion and extension of the joint and decreased range of motion, were shown in 40% and radiographic changes of bilateral coxofemoral joints were identified in 69% of a group of dogs. There are no sex predilections. Thirty-seven dogs were diagnosed as canine hip dysplasia (CHD; 10 cases), avascular necrosis of the femoral head (Legg-Calves-Perthes disease [LCPD]; 12 cases), fracture of the acetabulum (1 case), luxation(10 cases) and subluxation (15 cases), however, luxation and subluxation were identified in 11 dogs affected with CHD and LCPD. Causes of DJD in others (71case) were not identified. Radio-graphic findings identified included osteophyte formation at the attachment of the joint capsule (70%), sclerosis of the subchondral bone of the cranial acetabular edge (47%), remodeling of the femoral head (34%), thickening of the femoral neck(31%), perichondral osteophyte formation (31%), joint laxity (30%) and so on. All of the dogs diagnosed as CHD were large breed such as Retriever, Germain Shepherd, and Weimaraner and their age was under 1 year. This condition occurred bilaterally in 70% of affected animals. Dogs diagnosed as LCPD were young (under 1 year), small breed dogs. The incidence of LCPD is greater in Yorkshire Terrier, Miniature Pinscher and Poodle. This condition occurred unilaterally in 67% of affected animals. Clinical signs of dogs with unknown cause were shown in 15% and this condition occurred bilaterally in 75% of affected animals. Radiographic findings varied with patient's age and breed, however, the most common finding was osteophyte formation at the attachment of the joint capsule.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.21 no.2
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• pp.22-48
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• 1995

This study was investigated to search for the effects of the structure of each component in four-component O/W microemulsion system on its formation region, droplet size and stablilty. The results was that the more number of OH site, the shorter carbon chain length of polyol, the larger formation region of microemulsion was showed. The small microemulsion droplet was obtained on condition that the polatry of oil was large and carbon chain length of hydrophobic group of surfactant was long. In using satrated hydrocarbon (such as liquid paraffin, squalane) as dispersed phase, the stability of microemulsion was better than aromatic oil phase.