• Korean journal of applied entomology
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• v.54 no.3
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• pp.151-158
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• 2015

Chlorine dioxide ($ClO_2$) can be used as a fumigant to kill insects. However, some insects can exhibit an evasive behavior from chlorine dioxide. This evasive behavior decreases the efficiency of the insecticidal activity of chlorine dioxide. This study tested a hypothesis that heat treatment suppresses the evasive behavior and synergizes the control efficacy of chlorine dioxide. Chlorine dioxide fumigation killed the red flour beetle, Tribolium castaneum, under direct exposure condition to the chemical for 12 h with median lethal concentrations of 383.67 ppm (153.63 - 955.78 ppm: 95% confidence interval) for larvae and 397.75 ppm (354.46 - 446.13 ppm: 95% confidence interval) for adults. However, when they were treated with enough diet flour, they exhibited an evasive behavior by entering the diet, which significantly decreased the control efficacy of the fumigant. To clarify the evasive behavior, the choice test of the adults were performed in Y tube arena. The test adults significantly avoided the diet treated with chlorine dioxide, while the antennatectomized adults lost the avoidance behavior. Heat treatment using $46^{\circ}C$ for 6 h killed only 10% or less of T. castaneum. Interestingly, most adults were observed to come out of the diet under the heat treatment. Chlorine dioxide treatment even at 400 ppm for 6 h did not kill any T. castaneum. However, the combined treatment of chlorine dioxide with the heat treatment for 6 h resulted in 95% mortality. These results indicated that heat treatment suppressed the evasive behavior of T. castaneum and synergized the control efficacy of the chlorine dioxide fumigant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.1-7
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• 2002

To study the increased resistance in fish against Vibrio vulnificus known as an important agent of vibrio septicemia in human, we analyzed specific and nonspecific immune response in flounder after administration of V. vulnificus bacterins by oral route. It contained the comparison of antibody concentrations in the sera of flounder after oral administration by two different protocols with uncoated heat killed bacterin of V vulnificus (UHKB, 20 mg/kg body weight), i.e., 4 weeks continuously (group 4W) and taking 2 weeks resting period between the 1st and last week of administration (group 1-2-1W). Even though, 1-2-1W group showed significantly increased level of specific antibody in serum, it did not reach to that of 4W group. Certainly, flounder vaccinated twice a week for four weeks (20 mg/kg b.w.) showed increased concentration of specific antibody against V. vulnificus at week 2 after last administration by oral route and maintained throughout the experimental period. It also was confirmed by the increased numbers of specific antibody secreting cells (SASC) in the leukocytes isolated from the splenocytes of the flounder of 4W group at week 1 after last administration until the end of experimental period. However, enteric, acid-resistant film coated heat killed bacterin (ECHB) did not show both greater immune reaction for antibody production and faster elimination of a challenge dose of V. vulnificus compared with those of the UHKB. These results suggested that UHKB administered by oral route was very effective method to prevent the contamination of V vulnificus in flounder, and did not show the increased antigenicity by coating the surface with acid-resistant film.

• Journal of Life Science
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• v.29 no.2
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• pp.215-222
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• 2019

Muscle dysfunction may arise from skeletal muscle atrophy caused by aging, injury, oxidative stress, and hereditary disease. Powdered heat-killed Enterococcus faecalis (EF-2001) has anti-allergy, anti-inflammatory, and anti-tumor effects. However, its antioxidant and anti-atrophy effects are poorly characterized. In this study, we examined the effects of EF-2001 on muscle atrophy. To determine the protective effect of EF-2001 on oxidative stress, C2C12 myoblasts were treated with $H_2O_2$ to induce oxidative stress. This induced cell damage, which was reduced by treatment with EF-2001. The mechanism of EF-2001's effect was examined in response to oxidative stress. Treatment with EF-2001 reversed the expression of HSP70 and SOD1 proteins. Also, mRNA levels of Atrogin-1/MAFbx and MuRF1 increased under oxidative stress conditions but decreased following EF-2001 treatment. To evaluate muscle volume, two and three dimensional models of the muscles were analyzed using micro-CT. As expected, muscle volume decreased after sciatic denervation and recovered after oral administration of EF-2001. Therefore, EF-2001 is a candidate for the treatment of muscular atrophy, and future discovery of the additional effects of EF-2001 may yield further applications as a functional food with useful activities in various fields.

• Korean Journal Plant Pathology
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• v.1 no.1
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• pp.79-84
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• 1985

Some characteristics of the resistance induced by Erysiphe graminis f. sp. hordei on near-isogenic barley leaves were evaluated. Inoculation of heat-killed incompatible inducer conidia did not protect barley leaves against compatible challenger race when the inducer inoculum was removed prior to inoculation of challenger. However, the colony formation of challenger race was greatly reduced by 87.1 to $91.2\%$ when the heat-killed inducer inoculum was not removed from the leaves. Although incompatible inducer conidia were removed before they penetrate the host cell, colony formation of challenger was markedly decreased without change in its infection type. After penetrating the host cell by inducer, however, a change in infection types occurred on the challenged leaves. Irrespective of compatibility of previously inoculated inducer on middle part of leaves, there was no reduction in colony formation of challenger race both on the adjacent acropetal and basipetal parts of the same leaves free of inducer inoculation. The colonies formed on the basipetal part by challenger race showed normal 4 type, whereas the infection type of colonies formed on the acropetal part was somewhat changed, thereby sporulation being reduced. The possibility of translocation of resistance-inducing factors was discussed.

• Microbiology and Biotechnology Letters
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• v.37 no.1
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• pp.69-74
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• 2009

Lactic acid bacteria (LAB) were well known to enhance the intestinal health of human. For the development of pharmaceutical LAB. it was screened that the LAB with activity lowering the cholesterol in vitro and evaluated the hypocholestrolemic effect of live and heat-killed (HK) LAB on rats. The selected Lactobacillus plantarum CBT 1209 and Lactobacillus rhamnosus CBT 1702 had the deconjugation of bile salts and assimilation of cholesterol micelles activities from laboratory media, The mixture of 1702 and 1209 strains was administrated to the rats with high cholesterol diet. The experiment performed by 4 groups which were control, HCD, LLAB, HKLAB groups. The hypocholesterolemic effect of LAB (strains 1702, 1209) at blood level, the phenomena of AI decreasing through LDL-cholesterol dwindling, was assessed. This effect of 1702 and 1209 was enhanced when it comes to be the HKLAB more the live-LAB, This data means that the Lactobacillus rhamnosus CBT 1702 and Lactobacillus plantarum CBT 1209 were very useful functional ingredient for hypercholesterolemia.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.557-562
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• 2016

Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis are gram-negative bacteria frequently found in lesions from patients with periodontitis manifesting alveolar bone loss. Lipopolysaccharides are a major virulence factor of gram-negative bacteria. Bone resorption is known to be regulated by bacteria and their virulence factors. In the present study, we investigated the effects of A. actinomycetemcomitans and P. gingivalis on bone resorption. Heat-killed A. actinomycetemcomitans (HKAa) and heatkilled P. gingivalis (HKPg) induced bone loss in the femurs of mice after intraperitoneal administration. HKAa and HKPg augmented the differentiation of committed osteoclast precursors into osteoclasts, while they inhibited the differentiation of bone marrow-derived macrophages into osteoclasts. Concordant with the effects of the heat-killed whole cells, LPS purified from A. actinomycetemcomitans and P. gingivalis also augmented osteoclast differentiation from committed osteoclast precursors but attenuated it from bone marrow-derived macrophages. Taken together, these results suggest that the whole cells and lipopolysaccharides of A. actinomycetemcomitans and P. gingivalis induce the differentiation of committed osteoclast precursors into osteoclasts, potentially contributing to bone resorption in vivo.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.1053-1055
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• 2002

Recently CRT is getting large-sized, Flatness and High Fine Pitched in the meantime the raw material for shadow mask is in rapid progress of thinness, Low Thermal Expansion and high strength.Until now we have used AK(Aluminum Killed) & Invar(Fe-Ni alloy) materials for main raw material of shadow mask component. However recently Nb and Co addition and Nb+Co addition, which has advantage of Low Thermal Expansion and High Strength. has been developed as well as applying in mass production as CRT's trend has become more flat and fine pitch. Among of them, Co addition has been mass production as forming type (Flat CRT) with the beneficial effect of low thermal expansion & high strength for the first time. Since then Nb+Co addition has been used in mass production by the request of much higher strength of shadow mask component. In case of Nb addition, It's thermal expansion coefficient is a little lower than normal Invar and a little higher than Co addition, meanwhile Its Mechanical property is almost similar to Co Addition. The used samples of this experiment are 36%Ni + Fe, 32%Ni + 5%Co + Fe, 32%Ni + 5%Co + 0.3%Nb + Fe, 32%Ni + 0.3%Nb + Fe with heat treatment temperature of 600$^{\circ}C$, 650$^{\circ}C$, 700$^{\circ}C$, 750$^{\circ}C$, 800$^{\circ}C$, 850$^{\circ}C$, 900$^{\circ}C$ respectively under the condition of 15min holding time. After heat treatment, we have observed the change of mechanical property with addition of small elements through mechanical property investigation and metal structure observation as well as transition of thermal expansion coefficient by measuring of thermal expansion coefficient at 850$^{\circ}C$. In conclusion, 5%Co addition indicates that its thermal expansion coefficient is very similar under the condition of at 850$^{\circ}C$ for 15min 's heat treatment. From the experimental result it is suggested that Co addition is mostly suitable for Doming property and Nb addition is mostly suitable for Drop property.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.560-563
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• 2001

Geotrichum sp. MF01, isolated from oil-contaminated soil, utilized methyl ethyl ketone(MEK) as the sole source of carbon and energy. The strain MF01 showed a Michaelis-Menten kinetics on MEK, and the kinetic parameters determined for MEK degradation were; specific removal rate, $r_{max}$ = 0.14 $h^{-1}$; half-saturation constant, $K_m$ = 5.88 mM. The adsorption of MEK by heat-killed strain was 0.62 mg at 8.07 mg MEK indicating that the degradation was the primary removal mechanism over adsorption. Biodegradation of MEK was studied in a biofilter using perlite, vermiculite 0:1, v/v) as supporting material. During 57 days of biofilter operation, $^3h^{-1}$.

• Journal of Microbiology and Biotechnology
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• v.8 no.6
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• pp.588-594
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• 1998

Lactic acid bacteria were isolated from Kimchi and screened for bacteriocin production. Strain SE1, identified as Lactobacillus curvatus sp., showed the strongest inhibitory activity against Lactobacillus delbrueckii subsp. delbrueckii. The bacteriocin was inactivated by amyloglucosidase, trypsin, or protease K treatment. However, it maintained its activity under heat treatment at $100^{\circ}C$ for 60 min. The production of the bacteriocin had a growth-related mode and decreased around the early-stationary phase. The optimum temperature for the growth of L. curvatus SE1 was $37^{\circ}C$; however, the optimum temperature for bacteriocin production was $30^{\circ}C$. The bacteriocin activity was decreased by treatment with methanol, butanol, acetone, or chloroform, however, it was not affected by treatment with ethanol, iso-propanol, or cyclohexane. The inhibitory activity of bacteriocin was stable over a wide range of pHs (2 to 11). The bacteriocin from L. curvatus SE1 killed the indicator strain by a bactericidal mode of action. The bacteriocin from L. curvatus SE1 was partially purified by ethanol precipitation and ion exchange chromatography. SDS-polyacrylamide gel electrophoresis was used to determine the molecular weight of the bacteriocin by the bacteriocin activity test. The apparent molecular mass of the bacteriocin produced by L. curvatus SE1 was about 14 kDa.

• The Journal of the Korean Society for Microbiology
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• v.6 no.1
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• pp.41-60
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• 1971

The author prepared a tuberculin sample using synthetic medium for the test material in this experiment. For the test animals, guinea pigs, healthy calf sensitized with heat killed tubercle bacilli, naturally infected dairy cattle, goat, and calf were used. A reduced reactivity to tuberculin was observed when the second tuberculin test was done within 28 days after the first. The results obtained are summarized as follows. 1. The experimental HCSM tuberculin was shown the similar activities as the control products of standard tuberculin. 2. The potency of the experimental tuberculin preserved at $5^{\circ}C$ in refrigerator maintained the activity for three years. 3. By the intradermal test, the experimental tuberculin was proved to be specific to detect tuberculous dairy cattles and goats. 4. The appearance of skin reaction to tuberculin in naturally infected dairy cattles, goat and beef cattles was soft and diffuse swellings or circumscribed swellings accompanied by induration. 5. In the case of observing tuberculous dairy cattles, goats and beef cattles, as the criterion of the reaction to the caudal fold test, results were taken as positive when findings are either hard and circumscribed or soft and diffuse swellings of 3 mm at least in size. 6. The acid fast organisms isolated from tuberculin positive animals were identified mostly as M. tuberculosis var. bovis. 7. When the tuberculin test was repeated in the tuberculin positive animals, the reactivity decreased rapidly, lasting 4 weeks at least.