• 제목/요약/키워드: $E_b/N_t$

검색결과 468건 처리시간 0.027초

Color changes of ceramic veneers following glazing with respect to their composition

  • Kim, Sung-Joon;Woo, Jae-Man;Jo, Chan Woo;Park, Ju-Hee;Kim, Soo Kyung;Kahm, Se Hoon
    • The Journal of Advanced Prosthodontics
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    • 제11권1호
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    • pp.16-22
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    • 2019
  • PURPOSE. The purpose of this study was to compare the translucency and color changes of ceramic laminate veneers of different composition following glazing process. MATERIALS AND METHODS. $10mm{\times}10mm$ square specimens of 0.6 mm and 1.0 mm thicknesses were fabricated with IPS e.max Press (EM) and IPS e.max ZirPress (ZP) (n=10 per group). The color coordinates (CIE $L^*$ $a^*$ $b^*$) of the specimens were recorded with a colorimeter before and after glazing. The color changes and translucency parameter (TP) were calculated. For the comparisons with the composition and thicknesses between the 'not glazed' and 'glazed' groups, statistical analyses were done through paired T-test, independent two-sample T-test, and multiple regression analysis using SPSS 18.0 (P<.05). RESULTS. The TP of 0.6 mm EM was higher than that of 0.6 mm ZP. Total color difference (${\Delta}E^*$) between bare and glazed specimens of 1.0 mm EM was greater than that of 1.0 mm ZP with statistical significance. Following glazing, specimens from all groups showed statistically significant amount of decrease in $L^*$ and $a^*$, and statistically significant increase in $b^*$. The result of multiple regression analysis of EM and ZP showed that ${\Delta}L^*$ improved ${\Delta}E^*$. CONCLUSION. Within the limitations of present study, we conclude that translucency and color of ceramic laminate veneers change significantly after glazing process, and the nature and amount of changes vary with different compositions.

A Rapid and Simple Method for Construction and Expression of a Synthetic Human Growth Hormone Gene in Escherichia coli

  • Roytrakul, Sittiruk;Eurwilaichitr, Lily;Suprasongsin, Chittiwat;Panyim, Sakol
    • BMB Reports
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    • 제34권6호
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    • pp.502-508
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    • 2001
  • A cDNA, encoding the human growth hormone (hGH), was synthesized based on the known 191 amino acid sequence. Its codon usage was optimized for a high level expression in Escherichia coli. Unique restriction sites were incorporated throughout the gene to facilitate mutagenesis in further studies. To minimize an initiation translation problem, a 624-bp cassette that contained a ribosome binding site and a start codon were fused to the hGH-coding sequence that was flanked between the EcoRI and HindIII sites. The whole fragment was synthesized by an overlapped extension of eight long synthetic oligonucleotides. The four-short duplexes of DNA, which were first formed by annealing and filling-in with a Klenow fragment, were assembled to form a complete hGH gene. The hGH was cloned and expressed successfully using a pET17b plasmid that contained the T7 promoter. Recombinant hGH yielded as much as 20% of the total cellular proteins. However, the majority of the protein was in the form of insoluble inclusion bodies. N-terminal amino acid sequencing also showed that the hGH produced in E. coli contained formyl-methionine. This study provides a useful model for synthesis of the gene of interest and production of recombinant proteins in E. coli.

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녹차(綠茶)의 흡습특성(吸濕特性) (Sorption characteristics of Green Tea)

  • 이주백;정신교;손태화;최종욱
    • Current Research on Agriculture and Life Sciences
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    • 제4권
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    • pp.50-54
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    • 1986
  • 시판(市販) 녹차(綠茶)를 $20^{\circ}C$에서 상대습도(相對濕度)를 달리하여 저장하면서 흡습특성(吸濕特性)을 조사하였다. 녹차(綠茶)의 흡습속도(吸濕速度)는 저장상대습도(貯藏相對濕度)가 높을수록 컸으며 저장시간(貯藏時間)이 경과함에 따라 점차 감소하였다. 녹차(綠茶)의 등온흡습곡록(等溫吸濕曲綠)은 전형적인 Sigmoid 형태를 나타내었으며 상대습도(相對濕度)가 일정할 때 저장시간과 흡습속도와의 관계에서 다음과 같은 식(式)을 구할 수 있었다. $ln{\frac{dw}{dt}}=nln(t)+lnc$ B.E.T. 식(式)에 의해 구한 녹차(綠茶)의 단분자층수분함량(單分子層水分含量)은 7.01~7.87%로 나타났다. 저장시간(貯藏時間)과 흡습속도관계식(吸濕速度關係式)에서 구한 계산치 수분함량과 실측치수분함량을 비교한 결과 거의 유사한 경향이었다.

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MODULAR INVARIANTS UNDER THE ACTIONS OF SOME REFLECTION GROUPS RELATED TO WEYL GROUPS

  • Ishiguro, Kenshi;Koba, Takahiro;Miyauchi, Toshiyuki;Takigawa, Erika
    • 대한수학회보
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    • 제57권1호
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    • pp.207-218
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    • 2020
  • Some modular representations of reflection groups related to Weyl groups are considered. The rational cohomology of the classifying space of a compact connected Lie group G with a maximal torus T is expressed as the ring of invariants, H*(BG; ℚ) ≅ H*(BT; ℚ)W(G), which is a polynomial ring. If such Lie groups are locally isomorphic, the rational representations of their Weyl groups are equivalent. However, the integral representations need not be equivalent. Under the mod p reductions, we consider the structure of the rings, particularly for the Weyl group of symplectic groups Sp(n) and for the alternating groups An as the subgroup of W(SU(n)). We will ask if such rings of invariants are polynomial rings, and if each of them can be realized as the mod p cohomology of a space. For n = 3, 4, the rings under a conjugate of W(Sp(n)) are shown to be polynomial, and for n = 6, 8, they are non-polynomial. The structures of H*(BTn-1; 𝔽p)An will be also discussed for n = 3, 4.

Copepods (Cyclopoida) Associated with Compound Ascidians (Tunicata) from Korea, with Descriptions of Nine New Species

  • Lee, Jimin;Kim, Il-Hoi
    • Animal Systematics, Evolution and Diversity
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    • 제38권4호
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    • pp.167-198
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    • 2022
  • Ten species of copepods, including nine new species, associated with compound ascidians are recorded from Korean waters. Nine new species can be characterized by their major diagnostic features, as follows: Botryllophilus pentamerus n. sp. by having a five-annulated abdomen; B. paucisetatus n. sp. by the presence of four and three setae on the exopods of right and left leg 1, respectively; Haplostoma quadridens n. sp. by the presence of four lobes on the labrum and one seta plus four spines on the exopods of legs 1-4; H. paucidens n. sp. by the presence of only two spines on the distal segment of the antenna; Enterocola horridus n. sp. by having five setae on the antenna, no seta on the caudal ramus, and two setae on leg 5; E. longicaudatus n. sp. by having long caudal rami which are more than three times as long as wide; Thoracodelphys bisetata n. sp. by the presence of only two setae on the basis of the maxillule; T. cerasta n. sp. by the presence of a large, horn-like process on the distal margin of the basis of leg 2; and Unimeria hirsuta n. sp. by having three setae on the terminal segment of the maxilla. Zygomolgus didemni (Gotto, 1956) previously known only from European waters is reported from Korean waters, with a redescription and illustrations.

농흉 환자의 흉막액에서 분리된 Bifidobacterium dentium strain ATCC 15424의 유전체 염기서열 해독 (Genome sequence of Bifidobacterium dentium strain ATCC 15424 originally isolated from pleural fluid of an empyema patient)

  • 문지회;김수진;양석빈;장은영;신승윤;이진용;이재형
    • 미생물학회지
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    • 제55권3호
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    • pp.280-282
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    • 2019
  • 본 논문에서는 농흉 환자의 흉막액에서분리된 Bifidobacterium dentium ATCC 15424균주의 유전체 염기서열을 분석하여 보고한다. 이 균주의 유전체는 구강에서 분리된 다른 B. dentium 균주에 존재하지 않는 type III 및 IV secretion system proteins, N-acetylmuramoyl-L-alanine amidase 그리고 PRTRC system protein E를 암호화하는 유전자 등 247개의 ATCC 15424균주 특이적인 유전자들을 포함한다. 이 유전체의 서열 정보는 B. dentium의 자연적 변이와 세균 종 내의 유전체 다양성을 이해하는 데 유용할 것이다.

The Nature of Acid-Catalyzed Acetalization Reaction of 1,2-Propylene Glycol and Acetaldehyde

  • Cheng, Chen;Chen, Hui;Li, Xia;Hu, Jianli;Liang, Baochen
    • Korean Chemical Engineering Research
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    • 제53권4호
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    • pp.463-467
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    • 2015
  • We investigated catalytic activity of ion-exchange resins in acetalization of 1,2-propylene glycol with acetaldehyde. The impacts of reaction variables, such as temperature, reaction time, catalyst loading and feedstock composition, on the conversion of 1,2-propylene glycol were measured. The life of the catalyst was also studied. Furthermore, the reaction kinetics of 1,2-propylene glycol acetalization was studied. It was found that reaction rate followed the first-order kinetics to acetaldehyde and 1,2-propylene glycol, respectively. Therefore, overall acetalization reaction should follow the second-order reaction kinetics, expressed as. Key words: 1,2-propylene Glycol, 2,4-dimethyl-1,3-dioxolane, Ion-exchange Resin, Polyhydroxy Compounds, Acetalization $r=kC^{nA}_AC^{nB}_B=19.74e^{\frac{-6650}{T}}C^1_AC^1_B$.

한미 SMEDDS 실리마린 연질캅셀 제제의 임상약동학적 특성 (Clinical Pharmacokinetic Profiles of Hanmi SMEDDS Silymarin Soft Capsule Preparation)

  • 박민수;유내춘;김경환
    • Biomolecules & Therapeutics
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    • 제8권3호
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    • pp.269-275
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    • 2000
  • Silibinin(silybin) is the active component of silymarin from Silybum marianum and has hepato-protective effect. It is water-insoluble and has low bioavailability. To improve its bioavailability, self-micro-emulsifying drug delivery system (SMEDDS) has been developed by Hanmi Pharmaceutical Company (Silyma $n^{R}$ 140 soft capsule). In this study, the pharmacokinetic profiles of Silyma $n^{R}$ were examined and compared it with a reference preparation, L Caps140 of B Pharmaceutical Company. This study was approved by Yonsei University Severance Hospital IRB(approval No. CR0004) and followed the bioequivalence test guideline of Korean FDA. Eighteen healthy adult volunteers were allocated based on 2$\times$2 Latin square cross-over design. They were given 2 capsules (each contains silymarin 140 mg (60 mg as silibinin)) of either drug at each period and crossed over after a week of drug-free washout period. Blood concentration of silibinin was measured by HPLC. The $C_{max}$ and AUC of the Silyma $n^{R}$ were 1542.0 $\pm$ 402.7 ng/ml and 3323.3 $\pm$ 824.7 ng.h/ml, respectively, and were significantly higher than those of reference preparation. The Tmax was 0.8 $\pm$ 0.3 h and significantly shorter than reference preparation. The $K_{e}$ and $T_{1}$2/ of both drugs were comparable. Percent differences in means against reference preparation were +88.3% for AUC, +222.6% for $C_{max}$, and -61.1% for $T_{max}$./.>././.>./.

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A MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND B-MODE POLARIZATION WITH POLARBEAR

  • ADE, P.A.R.;AKIBA, Y.;ANTHONY, A.E.;ARNOLD, K.;ATLAS, M.;BARRON, D.;BOETTGER, D.;BORRILL, J.;CHAPMAN, S.;CHINONE, Y.;DOBBS, M.;ELLEFLOT, T.;ERRARD, J.;FABBIAN, G.;FENG, C.;FLANIGAN, D.;GILBERT, A.;GRAINGER, W.;HALVERSON, N.W.;HASEGAWA, M.;HATTORI, K.;HAZUMI, M.;HOLZAPFEL, W.L.;HORI, Y.;HOWARD, J.;HYLAND, P.;INOUE, Y.;JAEHNIG, G.C.;JAFFE, A.H.;KEATING, B.;KERMISH, Z.;KESKITALO, R.;KISNER, T.;JEUNE, M. LE;LEE, A.T.;LEITCH, E.M.;LINDER, E.;LUNGU, M.;MATSUDA, F.;MATSUMURA, T.;MENG, X.;MILLER, N.J.;MORII, H.;MOYERMAN, S.;MYERS, M.J.;NAVAROLI, M.;NISHINO, H.;ORLANDO, A.;PAAR, H.;PELOTON, J.;POLETTI, D.;QUEALY, E.;REBEIZ, G.
    • 천문학논총
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    • 제30권2호
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    • pp.625-628
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    • 2015
  • POLARBEAR is a ground-based experiment located in the Atacama desert of northern Chile. The experiment is designed to measure the Cosmic Microwave Background B-mode polarization at several arcminute resolution. The CMB B-mode polarization on degree angular scales is a unique signature of primordial gravitational waves from cosmic inflation and B-mode signal on sub-degree scales is induced by the gravitational lensing from large-scale structure. Science observations began in early 2012 with an array of 1.274 polarization sensitive antenna-couple Transition Edge Sensor (TES) bolometers at 150 GHz. We published the first CMB-only measurement of the B-mode polarization on sub-degree scales induced by gravitational lensing in December 2013 followed by the first measurement of the B-mode power spectrum on those scales in March 2014. In this proceedings, we review the physics of CMB B-modes and then describe the Polarbear experiment, observations, and recent results.

Effects of FIS Protein on rnpB Transcription in Escherichia coli

  • Choi, Hyun-Sook;Kim, Kwang-sun;Park, Jeong Won;Jung, Young Hwan;Lee, Younghoon
    • Molecules and Cells
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    • 제19권2호
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    • pp.239-245
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    • 2005
  • Factor for inversion stimulation (FIS), the Escherichia coli protein, is a positive regulator of the transcription of genes that encode stable RNA species, such as rRNA and tRNA. Transcription of the rnpB gene encoding M1 RNA, the catalytic subunit of E. coli RNase P, rapidly declines under stringent conditions, as does that of other stable RNAs. There are multiple putative FIS binding sites upstream of the rnpB promoter. We tested whether FIS binds to these sites, and if so, how it affects rnpB transcription. In vitro binding assays revealed specific binding of FIS to multiple sites in the rnpB promoter region. Interestingly, FIS bound not only to the upstream region of the promoter, but also to the region from +4 to +18. FIS activated rnpB transcription in vitro, but the level of activation was much lower than that of the rrnB promoter for rRNA. We also examined the effects of FIS on rnpB transcription in vivo using isogenic $fis^+$ and $fis^-$ strains. rnpB transcription was higher in the $fis^-$ than the $fis^+$ cells during the transitions from lag to exponential phase, and from exponential to stationary phase.