• The Journal of Korean Academy of Prosthodontics
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• v.31 no.2
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• pp.219-235
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• 1993

To determine the compatibilities of soft liming materials with denture cleansers by measuring the flexibility and elasticity and investigating the surface changes, 4 self-curing acrylic resin soft lining materials and 1 heat-curing silicone soft lining material were evaluated. 3mm thick x 20mm diameter discs of soft lining materials were individually bonded to a hard acrylic resin base as per manufacturers’instructions. Using an Instron universal testing machine, a static stress of $2kg/cm^2$ was applied for 30secs., the strain in compression was measured, giving an indication of the material’s flexibility. Elastic recovery was measured at 10secs. After removal of stress. Surface changes were investigated with Stereomicroscope. Then the specimens were immersed in 4alkaline peroxide denture cleansers and water as control group, tests were carried out at 1 day, 2 days, 7 days, 14 days and 30 days. The results were as follows : 1. Alkaline peroxide denture cleansers caused considerable porosity on the surface of selfcuring acrylic resin soft lining materials, and the most affected by the cleansers were Viscogel, Coe-Soft, Coe-Comfort, Lynal, in that order. 2. There was significant difference in flexibility between each soft lining material except for Coe-Comfort and Visco-gel, and every soft lining material was significant difference in elasticity. Especially Molloplast-B and Lynal were less flexible and more elastic than other soft lining materials(p<0.05). 3. The denture cleansers increased the flexibility and elasticity of the soft lining materials compared with control group(p<0.05), and Denalan, Polident, Kleenite, Efferdent affected the soft lining materials in that order. 4. There was significant difference in flexibility between each denture cleanser except for Denalan and Polident(p<0.05). Though Denalan and Polident, Denalan and Kleenite did not show significant difference in elasticity, other denture cleansers showed significant difference among each other(p<0.05). 5. Clinically Coe-Comfort, Coe-Soft and Visco-gel were incompatible with alkaline peroxide denture cleansers, and Lynal would be used within only 2 weeks. But Molloplast-B was compatible with alkaline peroxide denture cleansers.

• The Korean Journal of Mycology
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• v.8 no.1
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• pp.33-43
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• 1980

Thirteen strains or crosses of Lentinus edodes obtained from home and abroad were compared for their mycelial characteristics on artificial media. Eleven of them were selected and inoculated on logs in order to study for their productivity, and the morphological characteristics of the mushrooms were investigated. 1) Seven strains, i. e., 11001, 12001, 13005, 13012, 13015, 12004 and 20101 were grown well on the sawdust medium. 2) The best mycelial growth and establish­ment of infection on logs were obtained from strains 20101 and 11001. 3) The highest yield of the mushrooms on logs during the six year periods were obtained from strains 11001, 12001 and 20101. 4) The highest yield of the mushrooms usually was obtained on the fourth year after inoculation. 5) The fruit body productivity in terms of dry weight recovery was the highest in strains 13005 and 20101. 6) The most productive period of the mushrooms during the years depended on strains. Most prevalent types of the strains were summer and autumn growing types, and more mushrooms were produced during these periods. 7) Morphological characteristics of the mushroom were more or less dependent on environmental conditions. 8) Thicker fruit bodies and relatively uniform shapes of the mushroom were produced by strain 20101.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.4
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• pp.32-39
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• 1986

A strain of Aspergillus niger CAD 1 which produces considerable amount of beta-galactosidase was selected from extracellular beta-galctaosidase producing fungi isolated from soil. Optimal conditions for the enzyme from Aspergillus niger CAD 1 were the growth in wheat bran supplemented with 0.5% skim milk powder at $30^{\circ}C$ for 72 hrs. The crude enzyme was purified 1,387 fold through DEAE-cellulosc and Sephadex G-100 chromatographr and its recovery was 6.2%, The optimal pH and temperature for the purified enzyme were pH 4.5 ana $45^{\circ}C$, respectively. The Km and Vmax on ONPG were $3.57{\times}10^3M$ and 33.0 unit/mg protein, whereas those on lacose were $83.3{\times}10^3M$and 15.33 unit/mg protein, respectively, The activation energy for the enzyme was 9,900 cal/mol and the enzyme had no metal ion requirement for its activity and stability. The hydrolysis of lactose in skim milk, 4.8% lactose solution and acidic whey were 65%, 70% and 78% after 10 hrs incubation at $45^{\circ}C$, when 182 units of the enzyme were used 50ml of the substrate solutions.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.569-576
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• 1997

Fowl typhoid(FT) caused by Salmonella gallinarum is an infectious, egg-transmitted disease and characterized by swollen bronze liver, greenish-yellow diarrhea and high mortality in growing and adult chickens. Since 1992 the outbreak of FT has been increased. Several problems have been occurred such as absence of appropriate vaccines and lack of useful therapeutic methods. In these studies we investigated the pathogenicity of S gallinarum isolated in chickens. To compare the pathogenicity among the species of chickens, all chickens were challenged intramuscularly or orally with $1{\times}10^7$ CFU of S gallinarum. The brown-colored layers were more susceptible and white leghone chickens were more resistant than other species. In the brown layer chickens orally challenged, lethal doses ($LD_{50}$) of the isolates were inoculated at 1 day, 2 weeks, 4 weeks and 8 weeks old chickens with amount of $10^{4.2}$, $10^{4.7}$, $10^{7.0}$ and $10^{7.6}$ CFU, respectively. The chickens which were intramuscularly challenged with the less amount than $10^2$ CFU showed higher mortality than that of the chickens orally inoculated with same dose. Also, we investigated the recovery rates of bacteria from various organs of survival chickens which were challenged orally with $5{\times}l0^7$ CFU of S gallinarum. The bacteria was more frequently and isolated earlier from the liver and spleen than from any other ogans. In the pathogenicity test, the white-leghorn chickens which were known as resistant-strain against Salmonella were artificially immunosuppressed using bursectomy and/or dexamethasone treatment. Mortality of chickens with both bursectomized and treated with dexamethasone was higher(90%) than that of the control group(10%), the bursectomized chickens(10%) and the dexamethasone only treated group(20%). It was suggested that the protective mechanism in chickens against S gallinarum may be required both the functions of B-cells and T-cells.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.8
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• pp.737-742
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• 2015

Course correction munition are a weapson system for precision attacks and are assembled by applying a ballistic control system to existing projectiles. The roll control system is a subsystem of the ballistic control system and is placed between the guidance and control units inside of the projectile, which undergoes a 5000g lateral acceleration. Thus, it is very important to design the system to endure this load. Many developed countries evaluate the performance and safety of course correction munitions' parts using live-fire gun launch tests or a soft recovery system. However, these methods are expensive and slow. Thus, in this study, we develop impact analysis model of the roll control system using CAE. We apply the code to simulate impact phenomenon and use Johnson-Cook material model for modeling the high strain rate effect on the materials. We also design bearings in detail to analyze their behavior and verify the reliability of CAE model through gas-gun impact tests of the roll control system.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.69-75
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• 2004

Vibrio vulnificus is a halophilic bacterium frequently involved in human infection of seafood-associated primary septicemia and primary wound infection, mostly in men with over 40-years of age with underlying liver disease. The primary septicemia, which is the most common form of V. vulnificus infection in Korea, is defined as a systemic illness presenting fever or hypotension with recovery of V. vulnificus from blood or tissue without the apparent primary focus of infection. V. vulnificus typically do not produce acid from sucrose, but a case of primary septisemia was found in a patient at Chonnam K hospital in 1993 from whose blood a sucrose-fermenting strain was isolated. The patient was a 62-year-old man, heavy drinker, with underlying liver disease. He consumed a raw seafood dish two days before onset of the present illness. His symptoms were tenderness and swelling on the right foot. He rapidly developed septicemia, resulting in sudden death. V. vulnificus was isolated from the venous blood culture of the patient. On subculture, the isolate formed yellow colonies on TCBS and produced acid from sucrose. Because of these characteristics, species identification was not achieved by the API 20E and was delayed. Other characteristics of the isolate were identical to those of typical V. vulnificus. The isolate was common serotype O4A and possession of V. vulnificus-specific cytolysin gene was detected by PCR. The isolate was susceptible to all the antimicrobial agents tested including tetracycline, but was intermediate to colistin. In conclusion, it is important that microbiologists be aware of the presence of sucrose-positive V. vulnificus when he or she identifies gram-negative bacilli, which is isolated from the blood of patients with a recent history of raw seafood dish consumption.

• Korean Journal of Acupuncture
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• v.28 no.2
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• pp.59-75
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• 2011

Objectives : The Aim of this study was to investigate the clinical characteristics of male and female patients who have been suffered from headaches. The investigation was undertaken based on Qi-section(Methods of prescribing oriental herbal medicine) from DongEuiBoGam(東醫寶鑑). Methods: A statistical survey was conducted to compare the difference in clinical characteristics between male and female patients experiencing headaches. Oriental medical Diagnosis was used to classify all parients under the following categories Qi-deficiency (氣虛), Jing-dificiency (精虛), Food-stagnation (食積), Damp-accumulation (痰飮), Qi-stagnation (氣滯). Patients were treated using acupuncture therapy and herbal medicines. Results : 1. The ratio between male and female patients was about 1:3. 2. It showed that periods of illness were longer in female patients than in male patients. 3. The total number of treatments received was higher in female patients than in male patients. 4. Statistically, most female patients had Metopodynia and Migraines(Rt.), while male patients suffered mostly from Laryngalgia. 5. Male patients had feelings of strain in the head and female patients had splitting headaches. 6. Musculo-skeletal System and General Symptoms were frequently observed in male patients. Digestive System and Nervous System were frequently observed in female patients. 7. Results from oriental medical Diagnosis showed that male patients mostly had Qi-deficiency, ling-deficiency while the majority of female patients had Food-stagnation, Damp-accumulation, Qi-stagnation. 8. The recovery time for male patients was shorter than it was for female patients. The recurrence rate of the headaches were higher for female patients. Prognosis was better than in female patients in comparison to male patients. Conclusions : The statistical survey conducted was based on Qi-section of DongEuiBoGam. It had significant differences in clinical characteristics between male & femal patients.

• Elastomers and Composites
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• v.43 no.2
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• pp.88-103
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• 2008

This study was purposed to investigate the effects of surfactants and fillers on physical properties of hydrophilic polyvinylsiloxane dental impression materials (PVS). Incorporation of surfactants enhanced the hydrophilicity of the PVS, however, it induced increased viscosity and permanent deformation ratio, delayed setting, and decreased tensile strength. At high concentrations of surfactant, the tensile strength was observed to decrease significantly due to the internal pore formation. Especially, the hydrophilicity of the PVS was significantly enhanced with the addition of Silwet L-77. However, the viscosity, strain in compression, pore formation, and setting time increased whereas the elastic recovery rate and strength remarkably decreased. The PVS dental materials containing Span 20 showed the lowest degree of viscosity increase, delayed setting, pore formation, and hydrophilicity. The delayed setting, pore formation, and strength decrease caused by the incorporation of surfactant were improved by substituting the crystalline quartz filler with diatomaceous earth while the contact angle of PVS dental materials increased.

• The Korean Journal of Zoology
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• v.11 no.2
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• pp.48-54
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• 1968

Male rats of the Albino strain received methylene blue in the dose of 40mg/kg by subcutaneous injection and were subjected to total body X-irradiation, 300 roentgen, at 30 minutes after the injection. The protective effect of methylene blue against the single total body X-irradiation was studied for 24 days after X-irradiation with regard to the levels of liver glycogen, blood glucose, and electrolytes in serum. 1. Total body X-irradiation generally casued an increase in the levels of the liver glycogen and blood glucose in both methylene blue treated and control group during the entire experiment. 2. Methylene blue has been shown to delay slightly the increase of the levels of the liver glycogen and blood glucose when comparing with both groups which were given methylene blue and control saline injection before irradiation in the rats. 3. The delay in the increase in the levels of liver glycogen, in experimental group injected with methylene blue, significantly came in two phases. The first phase appeared at there days after the exposure, the second followed at eighth day. It appeared that the recovery phase was at nineteenth day. 4. During the experimental days the levels of the blood glucose increased generally, methylene blue, however, caused delay in two phases; the first at fifth day, the second at eighteenth day after the exposure to X-rays. 5. In electrolytes, there was not a significant difference. The levels of chloride were, however, slightly decreased in both groups, levels of potassium appeared different in two phases at first day and twelfth day, and the levels of sodium appeared to show irregular changes at the same levels, but there was no significant difference. 6. It may be considered that methylene blue greatly reduces the sensitivity of rats to X-rays, provided that methylene blue is given before the exposure.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.139-144
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• 1976

In order to investigate the properties of enzymes from two strains of mold, reported in the previous paper, (1) studies have been made concerning the characteristics of cellulase of Aspergillus niger-SM6 and Trichoderma viride-SM10, and summarized as follows. 1. In the semi-purification the recovery of ${\beta}-glucosidase$ was the highest when 80-90% ethanol was used and 0.8 saturation of $(NH_4)_2SO_4$. 2. The characteristics of the semi-purified enzyme were as follows. Aspergillus niger-SM6 Trichoderma viride-SM10 Optimum pH 3.5 4.0 pH stability 3.0-6.0 3.0-6.0 Optimum temperature $60^{\circ}C$ $60^{\circ}C$ Heat stability below $60^{\circ}C$ below $50^{\circ}C$ Optimum reaction time 30 min. 60 min. Optimum CMC concentration 3% 3% 3. The Km values of CMCase were 0.8% and 1.01 for Aspergillus niger-SM6 and Trichoderma viride-SM10, respectively. 4. In the strain of Aspergillus niger-SM6, there were high activity of xylanase and pectinase.