• The Journal of the Korean Society for Microbiology
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• v.14 no.1
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• pp.79-87
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• 1979

The immunosuppressive activity of newcastle disease virus(NDV) and some possible role of interferon(C-IF) in viral suppression of immune response were evaluated by SRBC-induced delayed-type hypersensitivity(DTH), rosette formation in spleen cells, number of lymphocytes in peripheral blood, hemagglutinin and hemolysin response to SRBC in ICR mice sensitized with SRBC. When NDV was inoculated before or after sensitization of mouse with SRBC, virus caused a marked inhibition of DTH, and its depressive effect was dependent on the time of virus inoculation in relation to SRBC sensitization or challenge. Rosette formation of spleen cells was significantly reduced by NDV infection. The degree of the depression of rosette formation was more prominent in mice inoculated before sensitization than after sensitization and could be related to the amount of serum interferon induced by the virus. Humoral response to SRBC of virus infected mouse was significantly depressed when NDV was inoculated 24 or 48 hours before sensitization. However, there was no difference in the response when the virus was inoculated 9 hour before and at the same time of sensitization or even after that. Lymphocytes in peripheral blood of mice were markedly diminished in numbers when NDV was inoculated 48 and 24 hour before sensitization with SRBC, but they were slightly augmented when the virus was inoculated 9 hour before and at the same time of sensitization. When UV-inactivated or heat-inactivated NDV was injected to the mouse at the same time of sensitization with SRBC, DTH and rosette formation of spleen cells were slightly depressed. DTH and rosette formation in mice treated with crude-IF were generally depressed as com pared with those of control mice. These studies suggest that the NDV causes a significant depression of cell-mediated immunity, whereas the humoral immune response is not inhibited markedly, and that the depression of immune response by NDV infection may be caused by interferon produced by NDV and direct viral activity.

• Journal of Mechanical Science and Technology
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• v.16 no.11
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• pp.1359-1366
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• 2002

The measurement of residual stresses by the hole-drilling method has been used to evaluate residual stresses in structural members. In this method, eccentricity can usually occur between the hole center and rosette gage center. In this study, we obtained the magnitude of the error due to eccentricity of a hole through the finite element analysis. To predict the magnitude of the error due to eccentricity of a hole in the biaxial residual stress field, it could be learned through the back propagation neural network. The prediction results of the error using the trained neural network showed good agreement with FE analyzed results.

• Animal cells and systems
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• v.6 no.3
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• pp.201-206
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• 2002

Three halacarid species belonging to the genus Copidognathus are recorded from the shallow subtidal sands at Ko Taenae Islet (sand dune) off Ko Pha-Ngan Island, Thailand: Copidognathus thailandicus n. sp., C. euryalus Bartsch, 1997 and C. orarius Otto, 2001. Copidognathus thailandicus n. sp. comes close with C. cribrosoma (Police, 1909) and C. cribellus Bartsch, 1993 due to dorsal plates completely covered with rosette pores. Dissimilarities among them are discussed. Copidognathus euryalus and C. orarius are recorded hove for the first time from Thailand and away from its type locality. The present paper is also the first contribution on the taxonomy of Halacaridae (Acari) from Thailand.

• Journal of the Korean Ceramic Society
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• v.37 no.5
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• pp.418-424
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• 2000

Effects of Ar ion damage prior to the phase transformation from pyrochlore to perovskite structure of PZT thin films have been investigated. As the degree of damage increased by increasing the acceleration voltage in the ion mass doping system, the phase transformation temperature decreased such that the temperature could be lowered down to 550$^{\circ}C$ when the film was damaged at 15 kV for 5 minutes. When the film was damaged prior to the heat treatment grain size of the perovskite thin films became less than 300${\AA}$. It turned out that relatively high value of the remanent polarization (about 30${\mu}$C/$\textrm{cm}^2$) as well as improvement of the fatigue characteristics to a large extent is closely related to the fine grain size of thus obtained PZT films.

• Environmental Analysis Health and Toxicology
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• v.2 no.1_2
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• pp.33-42
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• 1987

Experiments were performed to investigate effects of ethanol and saccharin on the immune system in rats. 4% ethanol and 0.02, 0.20, 2.00% saccharin solution in 4% ethanol were provided ad libitum by tap water for 4 weeks. Rats were sensitized and challenged with sheep red blood cells (S-RBC). Immune responses were evaluated by relative immuno organ weight, antibody production, Arthus reaction, delayed type hypersensitivity, and rosette forming cell. Ethanol exposure decreased thymus weight and delayed type hypersensitivity. A combined solution of ethanol and saccharin decreased water intake, growth rate, spleen weight, thymus weight, humoral and cellular immune response. Especially, a 2% saccharin solution in 4% ethanol very significantly suppressed cellular immunity.

• Environmental Analysis Health and Toxicology
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• v.3 no.1_2
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• pp.33-42
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• 1988

Dose-dependent, immune modulatory effects of aconitine and heated aconitine were studied in mice. Mice, administered aconitine and heated aconitine intraperitoneally every other day for 4 weeks, were sensitized and challenged with sheep red blood cells. Serum antibody titer, foot pad swelling and rosette forming cell number were measured to evaluate hurmoral and cell mediated immune responses. The results show that Humoral immune response was suppressed by aconitine 0.05 mg/kg and heated aconitine but increased by aconitine 0.10 mg/kg administration. Cell mediated immune response was suppressed in all groups. Especially heated aconitine administration significantly suppressed the cell mediated immune response. The number of peripheral circulating white blood cell was reduced by aconitine but was not affected by heated aconitine.

• Environmental Analysis Health and Toxicology
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• v.3 no.1_2
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• pp.9-19
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• 1988

The effect of rancid perilla oil on the immune response in mice was studied. ICR male mice were divided into 5 groups and were fed on the experimental diets for 4 weeks. Mice were sensitized and challenged with sheep red blood cell. Immune responses were evaluated by antibody production, Arthus reaction, delayed type hypersensitivity (DTH), Rosette forming cell and macrophage activity. Biochemical items were measured by serum protein and serum albumin. The weight of spleen, thymus and liver were measured. The rancid perilla oil diets decreased humoral and cellular immune responses, the number of peripheral circulating white blood cells and total protein and serum albumin. These results showed that the high rancid perilla oil diet decreased more humoral and cellular immune response, the number of peripheral circulating white blood cells, and total protein and serum albumin than the low rancid perilla oil diet did.

• The Plant Pathology Journal
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• v.21 no.2
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• pp.132-136
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• 2005

Two groups of phytoplasma were identified in chrysanthemum(Dendranthema grandiflorum) cv. Chunkwang showing distinct symptoms. Isolate Ph-ch1 showed symptoms of dwarf, witches'-broom, rosette and root death. The other isolate, Ph-ch2, revealed symptoms of dwarf, yellowing, leaf cupping, vein clearing and root death. The presence of phytoplasma structures in chrysanthemum leaf tissue was confirmed by transmission electron microscopy. The 16S rRNA gene was amplified from isolates Ph-ch1 and Ph-ch2 by PCR and cloned, and the nucleotide sequences were determined. In RFLP analysis, isolate Ph-ch2 showed profiles identical to Ph-ch1, except with restriction enzymes HhaI and MseI. The sequence data showed that isolate Ph-ch1 was most closely related to the aster yellows (AY) phytoplasma, and isolate Ph-ch2 was more closely related to stolbur phytoplasma than to AY phytoplasma. This is the first reported observation of stolbur phytoplasma in chrysanthemum species.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.86-86
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• 2009

The $(Na_{0.5}K_{0.5})NbO_3-SrTiO_3$ ceramics were produced by the conventional solid-state sintering method, and their microstructure and electrical properties were investigated. All $(Na_{0.5}K_{0.5})NbO_3-SrTiO_3$ ceramic show dense and homogeneous structure without the presence of the rosette structure. The dielectric constant, loss and remanent polarization of $(Na_{0.5}K_{0.5})NbO_3-SrTiO_3$ ceramics were superior to those of single composition $(Na_{0.5}K_{0.5})NbO_3$

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.11
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• pp.990-995
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• 1998

본 연구에서는 PZT(20/80)과 PZT(80/20) 금속 alkoxide용액을 Pt/Ti/$SiO_2$/Si 기판위에 상호 반복시킨 강유전성 PZT(20/80)/PZT(80/20) 이종층 박막을 제작하였다. 건조와 소결을 한번 행한 PZT 이종층 박막의 평균 두께는 약 80~90 nm이었다. 제작된 모든 PZT 박막은 rosette상이 없는 치밀하고 균질한 미세구조를 나타내었으며, 하부의 PZT층은 열처리시 상부 PZT층은 열처리시 상부 PZT 박막의 페로브스카이트 형성에 대해 nucleation site로 작용하였다. 유전상수, 피로특성 및 누설전류특성 등은 단일 조성의 PZT(20/80), PZT(80/20) 박막에 비해 우수한 특성을 나타내었다.