• 제목/요약/키워드: C center

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C-Band 용 FG-CPW 단일 평형 다이오드 혼합기 (A FG-CPW Single Balanced Diode Mixer for C-Band Application)

  • 배중선;이종철;김종헌;이병제;김남영
    • 한국전자파학회논문지
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    • 제12권3호
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    • pp.339-345
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    • 2001
  • 본 논문에서는 FG-CPW (Finite-Ground Coplanar Wave-Guide) 구조의 평형 다이오드 혼합기에 대해서 논의 된다. 주파수 대역 C-band로 선택하였고, RF는 5.72~5.82GHz, LO는 5.58~5.68GHz, 그리고 If 신호는 140 MHz가 사용되며, 이와 동일한 조건에서 마이크로스트립 혼합기를 제작하여 그 특성들을 비교하여 C-band 대역에서의 FG-CPW 의 응용 가능성을 제시한다. 단일 평형 형태를 위해 rat-race 결합기가 이용된다. CPW 구조를 갖는 LPF(low pass filter) 가 우수한 변환 손실 특성과 불필요한 하모닉들의 억제를 위해 사용된다. 5.635 GHz에서 4 dBm의 출력을 갖는 LO 신호가 입력될 때 6.2dB의 혼합기 변환 손실을 얻는다. 또한, LO-RF 격리특성과 LO-IF 격리 특성은 각각 30 dB와 40dB의 특성을 얻는다. 제시된 혼합기는 무선 LAN 분야에 응용될 수 있으리가 기대된다.

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Identification of a Variant Form of Cellular Inhibitor of Apoptosis Protein (c-IAP2) That Contains a Disrupted Ring Domain

  • Park, Sun-Mi;Kim, Ji-Su;Park, Ji-Hyun;Kang, Seung-Goo;Lee, Tae Ho
    • IMMUNE NETWORK
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    • 제2권3호
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    • pp.137-141
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    • 2002
  • Among the members of the inhibitor of apoptosis (IAP) protein family, only Livin and survivin have been reported to have variant forms. We have found a variant form of c-IAP2 through the interaction with the X protein of HBV using the yeast two-hybrid system. In contrast to the wild-type c-IAP2, the variant form has two stretches of sequence in the RING domain that are repeated in the C-terminus that would disrupt the RING domain. We demonstrate that the variant form has an inhibitory effect on TNF-mediated $NF-{\kappa}B$ activation unlike the wild-type c-IAP2, which increases TNFmediated $NF-{\kappa}B$ activation. These results suggest that this variant form has different activities from the wild-type and the RING domain may be involved in the regulation of TNF-induced $NF-{\kappa}B$ activation.

Lipid Peroxidation and the Thiobarbituric Acid Assay: Standardization of the Assay When Using Saturated and Unsaturated Fatty Acids

  • Rael, Leonard T.;Thomas, Gregory W.;Craun, Michael L.;Curtis, C. Gerald;Bar-Or, Raphael;Bar-Or, David
    • BMB Reports
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    • 제37권6호
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    • pp.749-752
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    • 2004
  • Saturated fatty acids are less vulnerable to lipid peroxidation than their unsaturated counterparts. In this investigation, individual fatty acids of the $C_{16}$, $C_{18}$ and $C_{20}$ families were subjected to the thiobarbituric (TBA) assay. These fatty acids were chosen based on their degree of saturation and configuration of double bonds. Interestingly, an assay threshold was reached where increasing the fatty acid concentration resulted in no additional decrease in the TBARS concentrations. Therefore, the linear range of TBARS inhibition was determined for fatty acids in the $C_{16}$ and $C_{20}$ families. The rate of TBARS inhibition was greater for the saturated than for unsaturated fatty acids, as measured from the slope of the linear range. These findings demonstrate the need to standardize the TBARS assay using multiple fatty acid concentrations when using this assay for measuring in vitro lipid peroxidation.

Evaluation of Embrittlement in Isochronal Aged Fe-Cr Alloys by Magnetic Hysteresis Loop Technique

  • Mohapatra, J.N.;Kamada, Y.;Kikuchi, H.;Kobayashi, S.;Echigoya, J.;Park, D.G.;Cheong, Y.M.
    • Journal of Magnetics
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    • 제16권2호
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    • pp.173-176
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    • 2011
  • Fe-Cr alloys with different Cr contents were prepared by an arc melting technique. The alloys were isochronally aged in the range from $400^{\circ}C$ to $900^{\circ}C$ with $50^{\circ}C$ steps with a holding time of 100 hours. The ageing produced embrittlement in the alloys due to either the formation of a Cr-rich ${\alpha}'$ phase or a $\sigma$ phase at high temperatures. Magnetic Hysteresis Loop (MHL) and Micro-Vickers hardness were measured at each step to correlate the magnetic and mechanical properties. Coercivity and hardness of the alloys were increased and remanence decreased up to 500-$550^{\circ}C$ due to formation of a Cr-rich ${\alpha}'$ phase. Beyond 500-$550^{\circ}C$ range, the coercivity and hardness decreased and remanence increased due to the coarsening or dissolution of the Cr-rich ${\alpha}'$ phase. In the Fe-48% Cr alloy, formation of the $\sigma$ phase at $700^{\circ}C$ reduced the maximum induction of the alloy significantly.

Ehlers-Danlos syndrome VIII with novel C1R variant accompanying white matter changes

  • Seo, Go Hun;Kim, Yoon-Myung;Ghang, Byeongzu;Kim, Gu-Hwan;Lee, Beom Hee
    • Journal of Genetic Medicine
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    • 제16권1호
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    • pp.43-47
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    • 2019
  • Ehlers-Danlos syndrome (EDS) VIII is an autosomal dominant inherited connective tissue disorder characterized by intractable periodontal inflammation, absence of gingiva, pretibial plaques, skin hyperextensibility, joint hypermobility, and tissue fragility with onset in the childhood or adolescence. In a recent report, heterozygous variants of the C1R or C1S related to the classical complement pathway were identified in families with history of EDS VIII. The current report describes a Korean 34-year-old female carrying a novel missense variant of C1R c.925T>G (p.Cys309Gly) and exhibiting early severe periodontitis, skin fragility, and joint hypermobility. The patient also had frontal, parietal, and temporal white matter brain lesions without definite vascular abnormalities on brain magnetic resonance imaging, which have not been surveyed meticulously in EDS VIII. Considering the genetic alteration of classic complement pathways in this condition, it is necessary to carefully observe multisystemic inflammation processes such as changes in brain white matter.

Characterization of Acyl-CoA Oxidases from the Lipolytic Yeast Candida aaseri SH14

  • Ibrahim, Zool Hilmi;Bae, Jung-Hoon;Sung, Bong Hyun;Kim, Mi-Jin;Rashid, Ahmad Hazri Ab;Sohn, Jung-Hoon
    • Journal of Microbiology and Biotechnology
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    • 제32권7호
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    • pp.949-954
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    • 2022
  • The lipolytic yeast Candida aaseri SH14 contains three Acyl-CoA oxidases (ACOXs) which are encoded by the CaAOX2, CaAOX4, and CaAOX5 genes and catalyze the first reaction in the β-oxidation of fatty acids. Here, the respective functions of the three CaAOX isozymes were studied by growth analysis of mutant strains constructed by a combination of three CaAOX mutations in minimal medium containing fatty acid as the sole carbon source. Substrate specificity of the CaAOX isozymes was analyzed using recombinant C. aaseri SH14 strains overexpressing the respective genes. CaAOX2 isozyme showed substrate specificity toward short- and medium-chain fatty acids (C6-C12), while CaAOX5 isozyme preferred long-chain fatty acid longer than C12. CaAOX4 isozyme revealed a preference for a broad substrate spectrum from C6-C16. Although the substrate specificity of CaAOX2 and CaAOX5 covers medium- and long-chain fatty acids, these two isozymes were insufficient for complete β-oxidation of long-chain fatty acids, and therefore CaAOX4 was indispensable.

Lactiplantibacillus plantarum LM1001 Improves Digestibility of Branched-Chain Amino Acids in Whey Proteins and Promotes Myogenesis in C2C12 Myotubes

  • Youngjin Lee;Yoon Ju So;Woo-Hyun Jung;Tae-Rahk Kim;Minn Sohn;Yu-Jin Jeong;Jee-Young Imm
    • 한국축산식품학회지
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    • 제44권4호
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    • pp.951-965
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    • 2024
  • Lactiplantibacillus plantarum is a valuable potential probiotic species with various proven health-beneficial effects. L. plantarum LM1001 strain was selected among ten strains of L. plantarum based on proteolytic activity on whey proteins. L. plantarum LM1001 produced higher concentrations of total free amino acids and branched-chain amino acids (Ile, Leu, and Val) than other L. plantarum strains. Treatment of C2C12 myotubes with whey protein culture supernatant (1%, 2% and 3%, v/v) using L. plantarum LM1001 significantly increased the expression of myogenic regulatory factors, such as Myf-5, MyoD, and myogenin, reflecting the promotion of myotubes formation (p<0.05). L. plantarum LM1001 displayed β-galactosidase activity but did not produce harmful β-glucuronidase. Thus, the intake of whey protein together with L. plantarum LM1001 has the potential to aid protein digestion and utilization.