• 제목/요약/키워드: ac susceptibility

검색결과 60건 처리시간 0.026초

Common Genetic Variations in the MUC5AC Gene are Not Related to Helicobacter pylori Serologic Status

  • Zhou, Cheng-Jiang;Zhang, Liu-Wei;Gao, Fang;Zhang, Bin;Wang, Ying;Chen, Da-Fang;Jia, Yan-Bin
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권24호
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    • pp.10719-10722
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    • 2015
  • Several lines of evidence suggest that MUC5AC genetic polymorphisms might confer susceptibility to H. pylori infection and therefore gastric cancer risk. We here assessed the association of common polymorphisms in the MUC5AC gene with H. pylori seroprevalence using an LD-based tagSNP approach in a north-western Chinese Han population. A total of 12 tagSNPs were successfully genotyped among 281 unrelated ethnic Han Chinese who had no cancer history, and no identifiable gastric disease or genetic disease. No significant association between any alleles, genotypes or haplotypes and H. pylori seroprevalence was observed. Our results suggest that common genetic variations in MUC5AC gene might not make a major contribution to the risk of H. pylori infection.

Associations of ABCB1 and XPC Genetic Polymorphisms with Susceptibility to Colorectal Cancer and Therapeutic Prognosis in a Chinese Population

  • Yue, Ai-Min;Xie, Zhen-Bin;Zhao, Hong-Feng;Guo, Shu-Ping;Shen, Yu-Hou;Wang, Hai-Pu
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권5호
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    • pp.3085-3091
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    • 2013
  • Associations between ABCB1 and XPC genetic polymorphisms and risk of developing colorectal cancer (CRC) as well as clinical outcomes in CRCs with chemotherapy were investigated. A case-control study was performed on the ABCB1 C3435T, G2677T/A and XPC Lys939Gln polymorphisms in 428 CRC cases and 450 hospitalbased, age and sex frequency-matched controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. We observed that the ABCB1 3435CT or CC+CT variants were significantly linked with increasing risk of developing CRC (adjusted OR (95% CI): 1.814 (1.237-2.660), P=0.0022; adjusted OR (95% CI): 1.605 (1.117-2.306), P=0.0102, respectively). Moreover, the distribution frequency of XPC AC genotype or AC+CC genotypes also showed a tendency towards increasing the suscepbility for CRC (P=0.0759 and P=0.0903, respectively). Kaplan-Meier curves showed that the ABCB1 C3435T variant was associated with a tendency toward longer progression-free survival (PFS) (n=343, Log-rank test: P=0.063), and the G2677T/A variant genotypes (GT+TT+GA+AA) with a tendency for longer OS in postoperative oxaliplatin-based patients (n=343, Log-rank test: P=0.082). However, no correlation of the XPC Lys939Gln polymorphism was found with PFS and OS in patients with postoperative oxaliplatin-based chemotherapy (n=343). Our study indicated that ABCB1 polymorphisms might be candidate pharmacogenomic factors for the prediction of CRC susceptibility, but not for prognosis with oxaliplatin chemosensitivity in CRC patients.

Synthesis and Photoinduced Magnetic Properties of a Mn12 Single Molecule Magnet by the cis-trans Isomerism of Azobenzene

  • George, Sheby M.;Kim, Jin-Kwon
    • Bulletin of the Korean Chemical Society
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    • 제30권5호
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    • pp.1143-1146
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    • 2009
  • [$Mn_{12}O_{12}(azo-L)_{16}(H_2O)_4$] (1), a new Mn12 single molecule magnet containing a photochromic azobenzene ligand, has been successfully synthesized by substitution of acetate ligand of Mn12 with 6-[4-{4-hexyloxyphenyl( azo)}-phenoxy]hexanoic-1-acid. The reversible photoisomerization of the azobenzene group was confirmed by UV-visible absorption spectroscopy. The temperature and field dependence of dc susceptibility and the temperature and the frequency dependence of ac susceptibility were measured for the cis and the trans isomer of 1. The magnetization value of the cis isomer in dc measurement is higher than that of the trans isomer. The cis isomer of 1 has a slower relaxation because cis-trans photoisomerization of the azobenzene group in peripheral ligands induces changes in its structure and dipole moment.

Hollandite $Nax(Ti_8-_xCr_x)O_{16}$의 이온 전송과 고유전율 (Ion Transport and High Frequency Dielectric of the Hollandite $Nax(Ti_8-_xCr_x)O_{16}$)

  • 신현만;이경섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 추계학술대회 논문집 전기설비전문위원
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    • pp.243-244
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    • 2008
  • The Velocity Autocorrelation Function (VAF) of the sodium ions is calculated for a range of temperature from 250K to 1000K and converted into the linear ac-conductivity and ac-susceptibility response via Fourier transformation. A peak is found in the conductivity around $6{\times}10^{12}Hz$ that has some of the character of a Poley absorption. Here it is shown to be due to an harmonically coupled site vibrations of the sodium atoms, which extend only over a limited range. At frequencies below the peak the conductivity tends towards a constant i.e. dc value corresponding to a constant flow of ions through the simulation cell. At high temperatures the conductivity due to this ion transport process behaves like a metal with an insulator to metal transition occurring around a specific temperature.

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B 첨가 $620^{\circ}C$급 터빈 케이싱용 고Cr 페라이트계 주강의 용접성에 미치는 탄소함량의 영향 (Effects of Carbon Content on the Weldability of B-Containing $620^{\circ}C$ Grade High Cr Ferritic Cast Steel for Turbine Casing)

  • 서원찬;방국수;지병하
    • 한국해양공학회지
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    • 제22권6호
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    • pp.41-45
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    • 2008
  • Effectsof carbon content on the weldability of B-containing 620 grade high Cr ferritic cast steels were investigated. Cast steel with lower carbon content of 0.07% showed lower HAZ hardness because of the formation of lower carbon martensite in HAZ. It also showed less solidification cracking susceptibility in weld metal because of the formation of delta ferrite. However, hot ductility showed no difference between cast steels with lower and higher carbon contents. Cast steel with lower carbon content showed greater HAZ softening after PWHT in the region heated between AC1 and AC3 because of its higher base metal hardness.

Susceptometry Application of Portable HTS SQUID-Based System

  • Timofeev, V.P.;Kim, C.G.;Shnyrkov, V.I.
    • Journal of Magnetics
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    • 제3권3호
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    • pp.86-88
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    • 1998
  • A portable RF HTS SQUID-based susceptometer was used for small size magnetized sample testing in weak DC (up to 200A/m) and AC (up to 4 A/m) magnetic fields. The system resolution for the magnetic moment is of the order of $1.6{\times}10^{-10} A.m^2$. The measured DC susceptibility of a tested sample agrees well with the value obtained by using a commercial liquid helium susceptometer.

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DYNAMICAL MAGNETIC PROPERTIES OF IRON-NITRIDE MAGNETIC FLUIDS

  • Mamiya, H.;Nakatani, I.
    • 한국자기학회지
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    • 제5권5호
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    • pp.815-818
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    • 1995
  • Ac susceptibility of iron-nitride magnetic fluids with various particle number densities was measured. Therelaxation time increases rapidly as the temperature decreases or the inter-particle interaction increases. The analysis of the data suggests that the activation energy is proportional to ${(k_{B}T/J_{typ})}^{\alpha}$ with $\alpha$~-0.24 in the lower temperature range in which the thermal energy is comparable to the magnetic dipole interaction.

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Association between the CYP1A2 rs762551 Polymorphism and Bladder Cancer Susceptibility: a Meta-Analysis Based on Case-Control Studies

  • Zeng, Yong;Jiang, Hua-Yong;Wei, Li;Xu, Wei-Dong;Wang, Ya-Jie;Wang, Ya-Di;Liu, Chuan
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권16호
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    • pp.7249-7254
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    • 2015
  • Background: Previous studies evaluated associations between the CYP1A2 rs762551 polymorphism and bladder cancer risk. However, the results were inconsistent. We therefore performed a meta-analysis of the published case-control studies to assess in detail the association between CYP1A2 rs762551 polymorphism and bladder cancer risk. Materials and Methods: PubMed, Embase and Web of Science were searched to identify relevant studies and the pooled odds ratio (OR) and 95 % confidence interval (95%CI) were calculated. Results: A total of seven articles including 3,013 cases and 2,771 controls were finally included. Overall, a significant association was found between the CYP1A2 rs762551 polymorphism and bladder cancer susceptibility for CC vs AA (OR=0.82, 95% CI=0.69~0.99), but no significant associations were found for the other three models (AC vs AA: OR=0.91, 95% CI=0.81~1.02; the dominant model: OR=0.90, 95% CI=0.80~1.00; the recessive model: OR=0.84, 95% CI =0.72~1.00). In the subgroup analysis by ethnicity, we detected significant associations between the CYP1A2 rs762551 polymorphism and bladder cancer susceptibility for GA vs GG (OR = 0.78, 95% CI =0.64~0.96) and for the recessive model (OR=0.80, 95% CI=0.66~0.96) in Caucasians, but not for Asians. Conclusions: The results from the meta-analysis suggested that the CYP1A2 rs762551 polymorphism is a protective factor for bladder cancer, especially in Caucasians.

Identification of a Cupin Protein Gene Responsible for Pathogenicity, Phage Susceptibility and LPS Synthesis of Acidovorax citrulli

  • Rahimi-Midani, Aryan;Kim, Min-Jung;Choi, Tae-Jin
    • The Plant Pathology Journal
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    • 제37권6호
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    • pp.555-565
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    • 2021
  • Bacteriophages infecting Acidovorax citrulli, the causal agent of bacterial fruit blotch, have been proven to be effective for the prevention and control of this disease. However, the occurrence of bacteriophage-resistant bacteria is one of hurdles in phage biocontrol and the understanding of phage resistance in this bacterium is an essential step. In this study, we aim to investigate possible phage resistance of A. citrulli and relationship between phage resistance and pathogenicity, and to isolate and characterize the genes involved in these phenomena. A phage-resistant and less-virulent mutant named as AC-17-G1 was isolated among 3,264 A. citrulli Tn5 mutants through serial spot assays and plaque assays followed by pathogenicity test using seed coating method. The mutant has the integrated Tn5 in the middle of a cupin protein gene. This mutant recovered its pathogenicity and phage sensitivity by complementation with corresponding wild-type gene. Site-directed mutation of this gene from wild-type by CRISPR/Cas9 system resulted in the loss of pathogenicity and acquisition of phage resistance. The growth of AC-17-G1 in King's B medium was much less than the wild-type, but the growth turned into normal in the medium supplemented with D-mannose 6-phosphate or D-fructose 6-phosphate indicating the cupin protein functions as a phosphomannos isomerase. Sodium dodecyl sulfa analysis of lipopolysaccharide (LPS) extracted from the mutant was smaller than that from wild-type. All these data suggest that the cupin protein is a phosphomannos isomerase involved in LPS synthesis, and LPS is an important determinant of pathogenicity and phage susceptibility of A. citrulli.

Effect of cement as mineral filler on the performance development of emulsified asphalt concrete

  • Liu, Baoju;Wu, Xiang;Shi, Jinyan;Wu, Xiaolong;Jiang, Junyi;Qin, Jiali
    • Advances in concrete construction
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    • 제10권6호
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    • pp.515-526
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    • 2020
  • Cold-mixed asphalt mixture is a widely recommended asphalt pavement materials with potentially economic and environmental benefits. Due to the reduction of natural non-renewable mineral resources, powder minerals with similar properties are considered as new mineral fillers in asphalt mixtures. This study explored the feasibility of using cement to replace natural limestone powder (LP) in emulsified asphalt concrete modified by styrene-butadiene styrene copolymer. The experimental tests, including compressive strength, Marshall stability as well as moisture susceptibility test, were used to investigate the mechanical properties, the Marshall stability, flow value, as well as the moisture damage. In addition, the influence of material composition on the performance of asphalt concrete is explained by the microstructure evolution of the pore structure, the interface transition zone (ITZ), and the micromorphology. Due to mineralogical reactivity of cement, its replacement part of LP improved the mechanical properties, Marshall stability, but it will reduce the moisture susceptibility and flow value. This is because with the increase of the cement substitution rate, the pore structure of the asphalt concrete is refined, the width of ITZ becomes smaller, and the microstructure is more compact. In addition, asphalt concrete with a larger nominal particle size (AC-16) has relatively better performance.