• 제목/요약/키워드: $pK_a$

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ASYMPTOTIC BEHAVIOR OF A-HARMONIC FUNCTIONS AND p-EXTREMAL LENGTH

  • Kim, Seok-Woo;Lee, Sang-Moon;Lee, Yong-Hah
    • 대한수학회보
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    • 제47권2호
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    • pp.423-432
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    • 2010
  • We describe the asymptotic behavior of functions of the Royden p-algebra in terms of p-extremal length. We also prove that each bounded $\cal{A}$-harmonic function with finite energy on a complete Riemannian manifold is uniquely determined by the behavior of the function along p-almost every curve.

MDM2 T309G has a Synergistic Effect with P21 ser31arg Single Nucleotide Polymorphisms on the Risk of Acute Myeloid Leukemia

  • Ebid, Gamal T.;Sedhom, Iman A.;El-Gammal, Mosaad M.;Moneer, Manar M.
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권9호
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    • pp.4315-4320
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    • 2012
  • Background: The P53 tumor suppressor gene plays a pivotal role in maintaining cellular homeostasis by preventing the propagation of genome mutations. P53 in its transcriptionally active form is capable of activating distinct target genes that contribute to either apoptosis or growth arrest, like P21. However, the MDM2 gene is a major negative regulator of P53. Single nucleotide polymorphisms (SNP) in codon Arg72Pro of P53 results in impairment of the tumor suppressor activity of the gene. A similar effect is caused by a SNP in codon 31 of P21. In contrast, a SNP in position 309 of MDM2 results in increased expression due to substitution of thymine by guanine. All three polymorphisms have been associated with increased risk of tumorigenesis. Aim of the study: We aimed to study the prevalence of SNPs in the P53 pathway involving the three genes, P53, P21 and MDM2, among acute myeloid leukemia (AML) patients and to compare it to apparently normal healthy controls for assessment of impact on risk. Results: We found that the P21 ser31arg heterozygous polymorphism increases the risk of AML (P value=0.017, OR=2.946, 95% CI=1.216-7.134). Although the MDM2 309G allele was itself without affect, it showed a synergistic effect with P21 ser/arg polymorphism (P value=0.003, OR=6.807, 95% CI=1.909-24.629). However, the MDM2 309T allele abolish risk effect of the P21 polymorphic allele (P value=0.71). There is no significant association of P53 arg72pro polymorphism on the risk of AML. Conclusion: We suggest that SNPs in the P53 pathway, especially the P21 ser31arg polymorphism and combined polymorphisms especially the P21/MDM2 might be genetic susceptibility factors in the pathogenesis of AML.

Purification and Characterization of 2,3-Dihydroxybiphenyl 1,2- Dioxygenase from Comamonas sp.

  • Lee Na Ri;Kwon Dae Young;Min Kyung Hee
    • 한국미생물학회:학술대회논문집
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    • 한국미생물학회 2001년도 추계학술대회
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    • pp.16-25
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    • 2001
  • A genomic library of biphenyl-degrading strain Comamonas sp. SMN4 was constructed by using the cosmid vector pWE15 and introduced into Escherichia coli. Of 1,000 recombinant clones tested, two clones that expressed 2,3-dihydroxybiphenyl 1,2-dioxygenase activity were found (named pNB 1 and pNB2). From pNB1 clone, subclone pNA210, demonstrated 2,3-dihydroxybiphenyl 1,2-dioxygenase activity, is isolated. 2,3-Dihydroxybiphenyl 1,2-dioxygenase (23DBDO, BphC) is an extradiol-type dioxygenase that involved in third step of biphenyl degradation pathway. The nucleotide sequence of the Comamonas sp. SMN4 gene bphC, which encodes 23DBDO, was cloned into a plasmid pQE30. The His-tagged 23DBDO produced by a recombinant Escherichia coli, SG 13009 (pREP4)(pNPC), and purified with a Ni-nitrilotriacetic acid resin affinity column using the His-bind Qiagen system. The His-tagged 23DBDO construction was active. SDS-PAGE analysis of the purified active 23DBDO gave a single band of 32 kDa; this is in agreement with the size of the bphC coding region. The 23DBDO exhibited maximum activity at pH 9.0. The CD data for the pHs, showed that this enzyme had a typical a-helical folding structures at neutral pHs ranged from pH 4.5 to pH 9.0. This structure maintained up to pH 10.5. However, this high stable folding strucure was converted to unfolded structure in acidic region (pH 2.5) or in high pH (pH 12.0). The result of CD spectra observed with pH effects on 23DBDO activity, suggested that charge transition by pH change have affected change of conformational structure for 23DBDO catalytic reaction. The $K_m$ for 2,3-dihydroxybiphenyl, 3-metylcatechol, 4-methylcatechol and catechol was 11.7 $\mu$M, 24 $\mu$M, 50 mM and 625 $\mu$M.

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한국인에서 Dystrobrevin Binding Protein 1(DTNBP1) 유전자의 다형성과 정신분열병의 연합에 대한 고찰 (Association Analysis of Polymorphisms on Dystrobrevin Binding Protein 1(DTNBP1) Gene with Schizophrenia in the Korean Population)

  • 문현일;이연정;박병래;신형두;최인근;한선호;우성일
    • 생물정신의학
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    • 제16권3호
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    • pp.149-158
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    • 2009
  • Objectives : This study was designed to investigate the association of schizophrenia and P1320, P1325, P1635, P1655, P1763 and SNP A polymorphisms on dystrobrevin binding protein 1(DTNBP1) gene in Korean patients. Methods : We analyzed P1320, P1325, P1635, P1655, P1763 and SNP A polymorphisms on DTNBP1 gene from their DNAs extracted from their blood in 388 Korean schizophrenic patients (male 198, female 190) and 372 control subjects(male 247, female 125). We compared the differences of genotype and allele distributions of the six polymorphisms on DTNBP1 gene between the Korean schizophrenic patient group and the normal control group. Results : There were no statistically significant differences of genotype and allele distributions of the P1320, P1325, P1635, P1655, P1763 and SNP A polymorphisms on DTNBP1 gene between the schizophrenic patient group and the normal control group. Conclusion : The results of this study suggest that P1320, P1325, P1635, P1655, P1763 and SNP A polymorphism on DTNBP1 gene do not have influence on the risk of the schizophnenic in the Korean population.

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A CLASS OF NEW NEAR-PERFECT NUMBERS

  • LI, YANBIN;LIAO, QUNYING
    • 대한수학회지
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    • 제52권4호
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    • pp.751-763
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    • 2015
  • Let ${\alpha}$ be a positive integer, and let $p_1$, $p_2$ be two distinct prime numbers with $p_1$ < $p_2$. By using elementary methods, we give two equivalent conditions of all even near-perfect numbers in the form $2^{\alpha}p_1p_2$ and $2^{\alpha}p_1^2p_2$, and obtain a lot of new near-perfect numbers which involve some special kinds of prime number pairs. One kind is exactly the new Mersenne conjecture's prime number pair. Another kind has the form $p_1=2^{{\alpha}+1}-1$ and $p_2={\frac{p^2_1+p_1+1}{3}}$, where the former is a Mersenne prime and the latter's behavior is very much like a Fermat number.

Device and Circuit Level Performance Comparison of Tunnel FET Architectures and Impact of Heterogeneous Gate Dielectric

  • Narang, Rakhi;Saxena, Manoj;Gupta, R.S.;Gupta, Mridula
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권3호
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    • pp.224-236
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    • 2013
  • This work presents a comparative study of four Double Gate tunnel FET (DG-TFET) architectures: conventional p-i-n DG-TFET, p-n-p-n DG-TFET, a gate dielectric engineered Heterogate (HG) p-i-n DG-TFET and a new device architecture with the merits of both Hetero Gate and p-n-p-n, i.e. HG p-n-p-n DG-TFET. It has been shown that, the problem of high gate capacitance along with low ON current for a p-i-n TFET, which severely hampers the circuit performance of TFET can be overcome by using a p-n-p-n TFET with a dielectric engineered Hetero-gate architecture (i.e. HG p-n-p-n). P-n-p-n architecture improves the ON current and the heterogeneous dielectric helps in reducing the gate capacitance and suppressing the ambipolar behavior. Moreover, the HG architecture does not degrade the output characteristics, unlike the gate drain underlap architecture, and effectively reduces the gate capacitance.

Cloning of p-Hydroxybenzoate Degradation Genes and the Overexpression of Protocatechuate 4,5-Dioxygenase from Pseudomonas sp. K82

  • Yoon, Young-Ho;Park, Soon-Ho;Leem, Sun-Hee;Kim, Seung-Il
    • Journal of Microbiology and Biotechnology
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    • 제16권12호
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    • pp.1995-1999
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    • 2006
  • Pseudomonas sp. K82 cultured in p-hydroxybenzoate induces protocatechuate 4,5-dioxygenase (PCD 4,5) for p-hydroxybenzoate degradation. In this study, a 6.0-kbp EcoR1 fragment containing p-hydroxybenzoate degradation genes was cloned from the genome of Pseudomonas sp. K82. Sequence analysis identified four genes, namely, pcaD, pcaA, pcaB, and pcaC genes known to be involved in p-hydroxybenzoate degradation. Two putative 4-hydroxyphenylpyruvate dioxygenases and one putative oxidoreductase were closely located by the p-hydroxybenzoate degradation genes. The gene arrangement and sequences of these p-hydroxybenzoate degradation genes were similar to those of Comamonas testosteroni and Pseudomonas ochraceae. PcaAB (PCD4,5) was overexpressed in the expression vector pGEX-4T-3, purified using a GST column, and confirmed to have protocatechuate 4,5-dioxygenase activity. The N-terminal amino acid sequences of overexpressed PCD4,5 were identical with those of purified PCD4,5 from Pseudomonas sp. K82.

Self-Sufficient Catalytic System of Human Cytochrome P450 4A11 and NADPH-P450 Reductase

  • Han, Song-Hee;Eun, Chang-Yong;Han, Jung-Soo;Chun, Young-Jin;Kim, Dong-Hyun;Yun, Chul-Ho;Kim, Dong-Hak
    • Biomolecules & Therapeutics
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    • 제17권2호
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    • pp.156-161
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    • 2009
  • The human cytochrome P450 4A11 is the major monooxygenase to oxidize the fatty acids and arachidonic acid. The production of 20-hydroxyeicosatetraenoic acid by P450 4A11 has been implicated in the regulation of vascular tone and blood pressure. Oxidation reaction by P450 4A11 requires its reduction partners, NADPH-P450 reductase (NPR). We report the functional expression in Escherichia coli of bicistronic constructs consisting of P450 4A11 encoded by the first cistron and the electron donor protein, NPR by the second. Typical P450 expression levels of wild type and several N-terminal modified mutants was observed in culture media and prepared membrane fractions. The expression of functional NPR in the constructed P450 4A11: NPR bicistronic system was clearly verified by reduction of nitroblue tetrazolium. Membrane preparation containing P450 4A11 and NPR efficiently oxidized lauric acid mainly to $\omega$-hydroxylauric acid. Bicistronic coexpression of P450 4A11 and NPR in E. coli cells can be extended toward identification of novel drug metabolites or therapeutic agents involved in P450 4A11 dependent signal pathways.

p관리도의 불량률의 변화 탐지 (Detection of Changes of the Population Fraction Nonconforming in the p Control Chart)

  • 장경;양문희
    • 품질경영학회지
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    • 제25권3호
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    • pp.74-85
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    • 1997
  • In this paper we calculate the subgroup size necessary for detecting the change of percent defective with several detection probabilities for orginal population fraction nonconforming p, changed population fraction nonconforming $p^*$, and the ratio k=$p^*$/p in the usage of p control charts. From our calculation we can know the error level of normal a, pp.oximation in detection probability calculation and recommend the subgroup size with lower error levels of normal a, pp.oximation, and then we show the reasonable subgroup size necessary for p, $p^*$, k, and the detection probability of the change of fraction nonconforming in a process. The information that we here show in tables will be useful when p control chart users decide the subgroup size in the p control chart users decide the subgroup size in the p control chart.

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SOME GROWTH ASPECTS OF COMPOSITE P-ADIC ENTIRE FUNCTIONS IN THE LIGHT OF THEIR (p, q)-TH RELATIVE ORDER AND (p, q)-TH RELATIVE TYPE

  • Biswas, Tanmay
    • 충청수학회지
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    • 제31권4호
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    • pp.429-460
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    • 2018
  • Let us consider that ${\mathbb{K}}$ be a complete ultrametric algebraically closed field and ${\mathcal{A}}({\mathbb{K}})$ be the ${\mathbb{K}}-algebra$ of entire functions on ${\mathbb{K}}$. In this paper we introduce the notions of (p, q)-th relative order and (p, q)-th relative type of p adic entire functions where p and q are any two positive integers and then study some growth properties of composite p adic entire functions in the light of their (p, q)-th relative order and (p, q)-th relative type. After that we show that (p, q) th relative order and (p, q)-th relative type are remain unchanged for derivatives under some certain conditions.