• 한국결정성장학회지
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• 제7권1호
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• pp.18-26
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• 1997

소결조제로 Y 3Alo012를 첨가한 {3- SiC 분말에 seed로서 1 wt%의 a- SiC 분말을 첨 가한 시편과 첨가하지 않은 시편을 1950$^{\circ}$C, argon 분위기에서 0.5~4시간 동안 소결하였다. S Seed로써 1 wt% a-SiC 분말의 첨가는 소결 도중에 길게 자란 업자틀의 성장을 가속시켰고, a a- SiC seed를 첨가한 시편에서 더 조대한 미세구조가 얻어졌다 .. a-SiC seed를 첨가하여 4시간 동안 소결한 시편의 파괴인성은 7.5 MPa'ml/2이었고, seed를 첨가하지 않은 시편의 파괴인성은 6 6.1 MPa'm1/2이었다 .. Seed를 첨가한 시편의 높은 파괴인성은 조대한 미세구조에 포함된 길게 자란 입자들에 의한 균열가교 기구의 활발한 작용에 기인한다.

• 대한화학회지
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• 제25권4호
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• pp.228-235
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• 1981

피리딘, ${\beta}$-피코린 및 3,5-루티딘과 요오드사이에 형성되는 전하이동착물을 사염화탄소 용액에서 자외선분광광도법을 사용하여 연구한 결과 $C_5H_5N{\cdot}I_2$, ${\beta}-C_5H_4(CH_3)N{\cdot}I_2$ 및 3,5-$C_5H_3(CH_3)_2N{\cdot}I_2$ 형의 1:1 분자착물이 형성됨을 알았다. 이들 착물생성에 대한 흡수최대는 온도가 상승함에 따라 blue shift되므로 이를 고려하여 각 온도에서의 평형상수를 구했다. 이 값으로부터 이들 착물생성에 대한 ${\Delta}H$, ${\Delta}G$및 ${\Delta}S$ 이 열역학적 파라미터를 산출하였다. 이 결과 착물의 상대적 안정도가 다음 순서로 증가함을 알수가 있었다. Pyridine < ${\beta}$-Picoline < 3,5-Lutidine. 이러한 결과는 dipole moment, steric hindrance effect 및 positive inductive effect에 의한 electron density의 증가 때문인 것으로 설명할 수 있었다. 그리고 polymethylbenzene-iodine CT-complex와도 비교 검토하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제8권2호
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• pp.187-194
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• 1995

Genetic variants of ${\alpha}s_1$-casein, ${\beta}$-casein, ${\kappa}$-casein and ${\beta}$-lactoglobulin were investigated by starch urea gel electrophoresis in milk samples of 280 Korean native cattle. A new ${\beta}$-casein variant, designated ${\beta}$-casein $A^4$, was found in milk samples of Korean native cattle. It has a much slower electrophoretic mobility than the ${\beta}$-casein $A^3$ variant in acid gel. This new variant appeared together with either ${\beta}$-casein $A^1$, $A^2$ or B variant. Gene frequencies and genotypic frequencies were estimated. Gene frequencies of four milk protein loci in Korean native cattle were compared with those of imported cattle breeds raised in Korea and Japanese brown cattle. Gene frequencies were ${\alpha}s_1$-casein B .846, ${\alpha}s_1$-casein C .154; ${\beta}$-casein $A^1$ .216, ${\beta}$-casein $A^2$ .666, ${\beta}$-casein $A^4$ .048, ${\beta}$-casein B .070; ${\kappa}$-casein A .648, ${\kappa}$-casein B .352; ${\beta}$-lactoglobulin A .148, ${\beta}$-lactoglobulin B .852. The population was in Hardy-Weinberg equilibrium at all milk protein loci. Gene frequencies of Korean native cattle were very similar to those of Japanese brown cattle. Interestingly, a new variant, ${\beta}$-casein $A^4$, was found only in Korean native cattle and Japanese brown cattle. These results support the hypothesis that Korean native cattle were used in the development of the Japanese brown cattle.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권7호
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• pp.352-357
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• 2004

The composites were fabricated, respectively, using 61vol.% SiC - 39vol.% TiB$_2$ and using 61vo1.% SiC - 39vo1.% WC powders with the liquid forming additives of 12wt% $Al_2$O$_3$＋Y$_2$O$_3$ by pressureless annealing at 180$0^{\circ}C$ for 4 hours. Reactions between SiC and transition metal TiB$_2$, WC were not observed in this microstructure. The result of phase analysis of composites by XRD revealed SiC(6H), TiB$_2$ and YAG(Al$_{5}$Y$_3$O$_{12}$) crystal phase on the SiC-TiB$_2$, and SiC(2H), WC and YAG(Al$_{5}$Y$_3$O$_{12}$) crystal phase on the SiC-WC composites. $\beta$\$\longrightarrow$$\alpha$-SiC phase transformation was ocurred on the SiC-TiB$_2$, but $\alpha$\$\longrightarrow$$\beta$-SiC reverse transformation was not occurred on the SiC-WC composites. The relative density, the vicker's hardness, the flexural strength and the fracture toughness showed respectively value of 96.2%, 13.34GPa, 310.19Mpa and 5.53Mpaㆍml/2 in SiC-WC composites. The electrical resistivity of the SiC-TiB$_2$ and the SiC-WC composites is all positive temperature coefficient resistance(PTCR) in the temperature ranges from $25^{\circ}C$ to 50$0^{\circ}C$. 2.64${\times}$10-2/$^{\circ}C$ of PTCR of SiC-WC was higher than 1.645${\times}$10-3/$^{\circ}C$ of SiC-TiB$_2$ composites.posites.

• 대한수학회지
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• 제49권2호
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• pp.379-394
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• 2012

Given an almost complex structure ($\mathbb^{C}^m$, J), $m\geq2$, that is defined by setting $\theta^{\alpha}=dz^{\alpha}+a_{\beta}^{\alpha}d\bar{z}^{\beta}$, ${\alpha}=1,\ldots$,m, to be (1, 0)-forms, we find conditions on ($a_{\beta}^{\alpha}$) for the existence of holomorphic functions an classify the almost complex structures by type ($\nu$,q). Then we determine types for several examples in $\mathbb{C}^2$ and $\mathbb{C}^3$ including the natural almost complex structure on $S^6$.

• 미생물학회지
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• 제35권4호
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• pp.289-295
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• 1999

Dunaliella bardawil의 적절한 생장과${\beta}$-carotene의 효과적인 축적 조건을 확립하기 위하여 염 농도, pH, 광량, 교반속도, 오존처리, 과산화수소 첨가 등의 영향을 비교하였고, 식용 식물성 기름을 이용한 ${\beta}$-carotene의 추출조건을 비교하였다. D. bardawil의 비생장 속도는 1N NaCl, pH 8.0 광량 80${\mu}$$E/\m^2/s$ , 70rpm 으로 배양 시에 0.168/hr로 최대를 나타냈다. 흰색 형광등을 250${\mu}$$E/\m^2/s$ 로 조사한 경우 ${\beta}$-carotene isomer 축적은 cis isomer가 trans isomer에 비해 높은 증가율을 보였다. ${\beta}$-carotene의 축적을 위하여 50${\mu}$M 과산화수소를 배양 2일 경과 후에 첨가한 경우 대조군의 축적율이 150${\mu}$g/ml인데 비해 324${\mu}$g/ml로, 200ppb로 2시간 오존 처리했을 때 약 1.8배 증가한 270${\mu}$g/ml이었다. 식용기름에 의한 37${\circ}C$에서의 추출효율은 올리브유, 참기름, 미강유, 옥수수유, 대두유의 순서로 나타났으며, 올리브유를 수층 부피의 9배로 첨가하고 50${\circ}C$에서 1시간 동안 sonication한 결과 96.95의 추출효율을 나타내었다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.95-95
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• 1997

Among the various receptor molecules discovered so far the ${\beta}$2-adrenergic receptors have been regarded as excellent model systems for the so called 7 transmembrane helix receptor and have been the focus of extensive studies. For the analysis of receptor structure and function a monoclonal antibody plays a crucial role, thus providing useful tools for the study of receptor. However, because of the minute quantity of receptor molecules which could be obtained from natural sources, the generation of specific monoclonal antibody against receptor molecules from the purified receptors has been regarded as virtually impractical in consideration of cost and experimental times. The purpose of the present study was to generate and characterize a monoclonal antibody against human ${\beta}$2-adrenergic receptor. For the production of antibody, C-terminal regions of the human ${\beta}$2-adrenergic receptor was produced as a fusion protein with Glutathion S-transferase (GST) in E. Coli. The expression of the fusion protein was identified by SDS-PAGE and Western blot using monoclonal anti-GST antibody. The fusion protein was purified to an apparent homogeniety by affinity chromatography with Glutathion Sepharose CL-4B and used as an antigen for the immunization of BALB/C mice. The Production of monoclonal antibody was achieved by fusion of the immunized spleen cells and SP/2-0 myeloma cells. Positive hybridomas were screened by ELISA and were cloned by two consecutive rounds of limiting dilution. The monoclonal antibody produced in this study (mAb${\beta}$C02) was IgM type and purified by immunoaffinity chromatography using anti-mouse IgM agarose as an affinity matrix. MAb${\beta}$C02 showed strong and specific immunoreactivity against both the fusion protein and human ${\beta}$2-adrenergic receptor in ELISA and Western blot. The molecular weight of immunoreactive band was 64 kDa and exactly coincided with the previously reported molecular weight of ${\beta}$2-adrenergic recepters. The results of the present study suggest that mAb${\beta}$C02 may be used for the study of receptor function and regulation in normal or nonphysiological status.

• Journal of Korean Neurosurgical Society
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• 제43권3호
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• pp.149-154
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• 2008

Objective: The aim of this study is to elucidate the effects of transforming growth factor-${\beta}$ (TGF-${\beta}$)1 and L-ascorbic acid on proteoglycan synthesis, and the relationship between Sox9, proteoglycan, and TGF-${\beta}1$ in intervertebral disc cells. Methods: Human intervertebral disc tissue was sequentially digested to 0.2% pronase and 0.025% collagenase in DMEM/F-12 media and extracted cells were cultured in $37^{\circ}C$, 5% $CO_2$ incubator. When intervertebral disc cells were cultured with TGF-${\beta}1$ or L-ascorbic acid, the production level of sulfated glycosaminoglycan (sGAG) was estimated by dimethyl methyleneblue (DMMB) assay. The changes of Sox9 mRNA and protein levels via TGF-${\beta}1$ were detected by RT-PCR and Western blot analysis in each. Results: The amount of sGAG was increased with the lapse of time during incubation, and sGAG content of pellet cultured cells was much larger than monolayer culture. When primary cultured intervertebral disc cells in monolayer and pellet cultures were treated by TGF-${\beta}1$ 20 ng, sGAG content of experimental group was increased significantly compared to control group in both cultures. L-Ascorbic acid of serial concentrations (50-300 ug/ml) increased sGAG content of mono layer cultured intervertebral disc cells significantly in statistics. The co-treatment of TGF-${\beta}1$ and L-ascorbic acid increased more sGAG production than respective treatment. After treating with TGF-${\beta}1$, Sox9 mRNA and protein expression rates were significantly increased in disc cells compared with the control group. Conclusion: This study suggests that TGF-${\beta}1$ would increase sulfated glycosaminoglycan (sGAG) and other proteoglycans such as versican by elevating Sox9 mRNA and protein expressions in order.

• Fisheries and Aquatic Sciences
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• 제19권2호
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• pp.11.1-11.7
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• 2016

In this study, purified peptides from shrimp waste hydrolysates (SWHs) were examined for their inhibitory effects against ${\beta}$-secretase. During consecutive purification using a Sephadex G-25 column chromatography and high performance liquid chromatography on a C18 column, a potent ${\beta}$-secretase inhibitory peptide Asp-Val-Leu-Phe-His (629 Da) was isolated and identified from SWH24 by Q-TOF MS/MS and the $IC_{50}$ value was determined to be $92.70{\mu}M$. The ${\beta}$-secretase inhibition patterns of the purified peptides were found to be competitive. Among synthesized ${\beta}$-secretase inhibitory peptides, Leu-Phe-His had higher ${\beta}$-secretase inhibitory activity than the others. The result of this study suggests that the ${\beta}$-secretase inhibitory peptide derived from SWH24 could be potential candidates to develop nutraceuticals and pharmaceuticals.

• 호남수학학술지
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• 제2권1호
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• pp.1-8
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• 1980

논문(論文)[3] (본(本) 논문(論文) 제1부(第1部))에서 미분가능다양체(微分可能多樣體) M 위의 (n-1)차(次) 미분형식(微分型式) ${\beta}^{(n-1)}$이 Compact인 Carrier를 가지면 ${\int}d{\beta}^{(n-1)}=0$이며, (p-1)차(次) 미분형식(微分型式) ${\beta}^{(p-1)}$과 p차(次) 미분가능쇄(微分可能쇄鎖) $C^{(p)}=\Sigma\limits_ik_iS_i{^{(p)}}$에 대(對)하여 ${\int\limits_{c^{(p)}}}d{\beta}^{(p-1)}={\int\limits_{{\partial}{c}^{(p)}}}{\beta}^{(p-1)}$이 성립(成立) (Stokes 정리(定理)의 일반화(一般化))⋯등(等) M위의 적분(積分)에 관한 여러 가지 성질(性質)들을 구명(究明)하였다. 이 성질(性質)들을 토태(土台)로 하여 본(本) 논문(論文)에서는; 제2절(第2節)에서 미분가능다양체(微分可能多樣體) M위의 Lie 도함수(導函數)의 정의(定義)와 Lie적분(微分)에 관(關)한 여러가지 성질(性質)들을 고찰(考察)하고, 제3절(第3節)에서 div X와 Laplace 작용소(作用素) ${\Delta}f$의 정의(定義) 및 실(實) n차원(次元) 가부호미분가능(可符號微分可能) 다양체(多樣體) M 위에서의 divX와 ${\Delta}f$의 적분(積分)에 관(關)한 성질(性質), 즉(卽) $V=\sqrt{{\mid}g{\mid}}dx^1{\Lambda}{\cdots}{\Lambda}dx^n{\in}A^n(M)$에 대(對)하여 $$\int_MdivXV\limits=\int_M{\Delta}fv=0$$인 관계(關係)가 성립(成立)함을 구명(究明)한다. (정리(定理) 3.3)