• 제목/요약/키워드: inv(2)

검색결과 58건 처리시간 0.022초

$MgO-SiO_2$ 계 자기에 관한 연구(II) (A Study on the Porcelain Body of $MgO-SiO_2$ System(II))

  • 이응상;이종근;최성철;안기성
    • 한국세라믹학회지
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    • 제20권3호
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    • pp.243-249
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    • 1983
  • This study has examined on the effect for the fitting in porcelain body of MgO-SiO system. The mixture was made of correponding in the theoretical composition of enstatite with Kyul Sung Talc and sea water magnesia cake. Hyup Jin Kaolin as clay minerals to give the mixture plasticity was added 10% by weight of the mixture. Feldspar was added inv various kinds of 1%-20% by weight of the above mixture. After the physical properties and microstructures were carefully examined the following results were obtained. 1. The addition amount of feldspar should generally be from 5% to 10% by weight of the mixture to be good for the properties of the strength and the range of the firing temperature. 2. The 5% addition amount of feldspar was good for the apparent bulk density. 3. 5% and 10% additions showed up stably excellant with respect to the various properties Therefore when we considered the apparent bulk density and the thermal shock resistance 5% addition amount of feldspar showed the most excellant properties between $1350^{\circ}C$ and $1400^{\circ}C$.

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오리 도체에서 등온유전자증폭기법을 이용한 Salmonella spp. 신속 고감도 검출 기법 연구 (Rapid and Sensitive Detection of Salmonella spp. by Using a Loop-Mediated Isothermal Amplification Assay in Duck Carcass Sample)

  • 조애리;동희진;조성범
    • 한국축산식품학회지
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    • 제33권5호
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    • pp.655-663
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    • 2013
  • 본 연구에서는 Salmonella invA 유전자를 마커로 Salmonella 특이 LAMP primer를 제작하였고, inclusivity 및 exclusivity 실험 결과는 각각 100%로 관찰되었다. 순수 배양된 Salmonella 희석액에서의 검출한계는 18.17분에서 $3.2{\times}10^3$ CFU/mL ($R^2$ = 0.9446)으로 관찰되어 신속 간단하고 민감도가 높아 Salmonella 검출을 위한 방법으로 효과적일 뿐만 아니라 간접적인 정량기법으로서도 활용 가능함을 알 수 있었다. 1차 증균 배지인 BPW에 S. Enteritidis 접종 후 0시간 및 12시간 배양 후 LAMP의 검출한계는 각각 $3.2{\times}10^3$ CFU/mL 및 $3.2{\times}10^0$ CFU/mL으로 관찰되었고, 오리도체 시료가 포함된 BPW에 S. Enteritidis 접종 후 0시간 및 12시간 증균액에서의 LAMP 검출한계는 각각 $3.2{\times}10^3$ CFU/mL 및 $3.2{\times}10^0$ CFU/mL으로 관찰되어 PCR과 비교하였을 때 오리도체시료 성분에 의한 영향이 비교적 낮았음을 알 수 있었다. 또한, 실제 도압장에서 채취한 오리도체시료를 BPW에 6시간 배양한 1차 증균액에 개발한 LAMP기법을 적용한 결과, 96%의 민감도 및 84%의 특이도를 보여 오리도체에서의 Salmonella 신속 스크리닝 기법으로서 효과적으로 활용될 수 있음을 알 수 있었다.

Streptococcus sp. 배양 여과물(HAIRCLETM)의 모발 개선 효과 (Hair Revitalization Effects of Streptococcus sp. Strain Culture Medium Filtrate (HAIRCLETM))

  • 박혜림;김하연;김진영;오신석;강필선;이강혁;임정혁;신송석
    • 대한화장품학회지
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    • 제48권2호
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    • pp.169-180
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    • 2022
  • Streptococcus sp.는 일반적으로 히알루론산을 생산하는 균주로 알려져 있다. 본 연구에서는 Streptococcus 균주가 배양하면서 만들어내는 여러 대사산물 중 히알루론산 이외의 영양성분에 주목하였다. 히알루론산이 생성되지 않은 조건에서의 Streptococcus sp. 배양 여과물로 모발 실험용 샘플(HAIRCLETM)을 제조하고 모발에 미치는 효과를 확인하였다. 모발의 인장강도는 만능시험기(universal testing machine, UTM)로 측정하였으며, 모발표면의 미세구조는 atomic force microscope (AFM)으로 분석하였다. 이 연구를 통해 Streptococcus sp. 배양 여과물은 손상된 모표피개선, 마찰력증가 및 모발강도의 증가 등의 모발개선 효과가 있는 것으로 확인되었다. 또한 in vitro 모발관련 실험을 통해 Streptococcus sp. 배양 여과물이 모발성장인자인 혈관내피세포 성장인자(vascular endothelial growth factor, VEGF), 간세포성장인자(hepatocyte growth factor, HGF), Wnt10b의 발현 촉진 효과가 있음을 확인 하였으며, 안드로젠 수용체(androgen receptor, AR)와 TGF-β2 발현을 저해시켜 남성형 탈모완화 효과도 있음을 확인 하였다. 또한 산화스트레스에 대해 장벽 관련 인자(INV, CLDN-1)의 발현을 증가시키고, 염증성 인자인 COX-2 발현을 억제시킴으로써 손상된 두피 장벽을 개선하고 유도된 염증을 완화시키는 효능이 있음을 확인하였다.

Detection of Salmonella typhi by Loop-mediated Isothermal Amplification Assay

  • 조윤경
    • 대한의생명과학회지
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    • 제14권2호
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    • pp.115-118
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    • 2008
  • Salmonella typhi is frequent causes of foodborne illness and its detection is important for monitoring disease progression. In this study, by using general PCR and novel LAMP (Loop Mediated Isothermal Amplification) assay, we evaluated the usefulness of LAMP assay for detection of Salmonella typhi. In this LAMP assay, forward inner primer (FIP) and back inner primer (BIP) was specially designed for recognizing target invA gene. Target DNA was amplified and visualized as ladder-like pattern of bands on agarose gel within 60 min under isothermal conditions at $65^{\circ}C$. When the sensitivity and reproducibility of LAMP were compared to general PCR, there was no difference of reproducibility but sensitivity of LAMP assay was more efficient than PCR (the detection limit of LAMP assay was 30 fg, while the PCR assay was 3 pg). These results indicate that the LAMP assay is a potential and valuable means for detection of Salmonella typhi, especially for its rapidity, simplicity and low cost.

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ON g(x)-INVO CLEAN RINGS

  • El Maalmi, Mourad;Mouanis, Hakima
    • 대한수학회논문집
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    • 제35권2호
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    • pp.455-468
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    • 2020
  • An element in a ring R with identity is called invo-clean if it is the sum of an idempotent and an involution and R is called invoclean if every element of R is invo-clean. Let C(R) be the center of a ring R and g(x) be a fixed polynomial in C(R)[x]. We introduce the new notion of g(x)-invo clean. R is called g(x)-invo if every element in R is a sum of an involution and a root of g(x). In this paper, we investigate many properties and examples of g(x)-invo clean rings. Moreover, we characterize invo-clean as g(x)-invo clean rings where g(x) = (x-a)(x-b), a, b ∈ C(R) and b - a ∈ Inv(R). Finally, some classes of g(x)-invo clean rings are discussed.

국내시장지향 벤처와 해외시장지향 벤처의 특성 비교 (Comparison of the Characteristics between Domestic New Ventures and International New Ventures)

  • 박상문
    • 기술혁신학회지
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    • 제8권2호
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    • pp.809-831
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    • 2005
  • This paper explores the difference between domestic new ventures(DNV) and international new ventures (INV). New ventures pursue business opportunities in their target markets armed with experienced founding team, distinctive competitive strategies, and different entry time at foreign market. As a result, INVs were founded by larger number of founding team and more experienced in international business. Also INVs enter earlier global market and pursue business opportunities than DNVs. in In terms of competitive strategy, INVs highlight continuous quality improvement and diverse customers compared to DNVs focused on intellectual property rights. INVs get higher profitabilities in financial performance. Finally, this paper suggests some managerial implications for new venture to explore business opportunities in the global markets.

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Genetic and Environmental Control of Salmonella Invasion

  • Altier, Craig
    • Journal of Microbiology
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    • 제43권spc1호
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    • pp.85-92
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    • 2005
  • An early step in the pathogenesis of non-typhoidal Salmonella species is the ability to penetrate the intestinal epithelial monolayer. This process of cell invasion requires the production and transport of secreted effector proteins by a type III secretion apparatus encoded in Salmonella pathogenicity island I (SPI-1). The control of invasion involves a number of genetic regulators and environmental stimuli in complex relationships. SPI-1 itself encodes several transcriptional regulators (HilA, HilD, HilC, and InvF) with overlapping sets of target genes. These regulators are, in turn, controlled by both positive and regulators outside SPI-1, including the two-component regulators BarA/SirA and PhoP/Q, and the csr post-transcriptional control system. Additionally, several environmental conditions are known to regulate invasion, including pH, osmolarity, oxygen tension, bile, $Mg^{2+}$ concentration, and short chain fatty acids. This review will discuss the current understanding of invasion control, with emphasis on the interaction of environmental factors with genetic regulators that leads to productive infection.

도축돈에서 분리된 살모넬라의 혈청형 및 유전형 (Serotypes and genotypes of Salmonella isolates from slaughtered pigs)

  • 최원종;정지헌;원호근;강정무;한태욱
    • 한국동물위생학회지
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    • 제31권1호
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    • pp.1-16
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    • 2008
  • Salmonella infections cause the disease in pigs but also some zoonotic Salmonella serotypes can be transmitted to human through swine products, resulting in food poisoning. The objective of this study was to investigate the bacteriological prevalence and detection of invA gene using Salmonella specific polymerase chain reaction (PCR), the epidemiological characteristics related to Salmonella strains cultured from pig samples in Gangwon areas using serotyping, random amplified polymorphic DNA (RAPD) and pulsed field gel electrophoresis (PFGE) methods. During the period of November 2001 through April 2002, 1,174 ileocecal lymph node were collected from the slaughtered pigs raised in 38 farms located in Gangwon province. The samples were submerged in boiling water and macerated in saline and lymph node homogenates were inoculated into Tetrathionate broth with iodine (TTB, Difco, 0.5% iodine was added) for enrichment growth. Then additional tests were performed using several mediums, and suspects were identified by API 20E kit (BioMerieux) and PCR. Of total 1,174 samples from 38 farms, 44 (3.7%) were isolated as Salmonella spp from 13 farms (34.2%). Of 44 isolates, 31 were in Yangyang region, followed by 9 in Goseong, 2 in both Gangneung and Sokcho. However, there was no difference in regional isolation frequency. All isolates have a 521bp amplified product in Salmonella specific PCR with primer invA which encodes in proteins for invasion of epithelial cells. Of 44 recovered serotypes, 23 (52.3%) were S Eingedi, 10 (22.7%) S Schwarzengrund, 9 (20.5%) S Typhimurium, and 2 (4.5%) S Mbandaka. In RAPD analysis, there appeared to be unique bands distinguishing each serotype, although similarities exist between the different serotypes. Four serotypes of 44 Salmonella isolates appeared to fall into 14 different RAPD types. In PFGE analysis, 9 S Typhimurium were tested with XbaI enzyme and SpeI enzyme. The combination of results obtained with two enzymes subdivided the 9 S Typhimurium into 4 PFGE types.

A SM2 Elliptic Curve Threshold Signature Scheme without a Trusted Center

  • Jie, Yan;Yu, Lu;Li-yun, Chen;Wei, Nie
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권2호
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    • pp.897-913
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    • 2016
  • Threshold signature is very important in identity authentication and some other applications. In December 2010, Chinese Encryption Administration released the SM2 elliptic curve digital signature algorithm as the first standard of the digital signature algorithm in China. At present, the papers on the threshold signature scheme based on this algorithm are few. A SM2 elliptic curve threshold signature scheme without a trusted center is proposed according to the Joint-Shamir-RSS algorithm, the Joint-Shamir-ZSS algorithm, the sum or diff-SS algorithm, the Mul-SS algorithm, the Inv-SS algorithm and the PM-SS algorithm. The proposed scheme is analyzed from correctness, security and efficiency. The correctness analysis shows that the proposed scheme can realize the effective threshold signature. The security analysis shows that the proposed scheme can resist some kinds of common attacks. The efficiency analysis shows that if the same secret sharing algorithms are used to design the threshold signature schemes, the SM2 elliptic curve threshold signature scheme will be more efficient than the threshold signature scheme based on ECDSA.