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Structural and functional evidence for two separate oligosaccharide binding sites of Pasteurella multocida hyaluronan synthase

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Advances in Enzyme Research 2013年第4期1卷 97-111页

作者： Floor K. Kooy hendrik h. Beeftink michel h. m. Eppink Johannes Tramper Gerrit Eggink Carmen G. Boeriu Bioprocess Engineering Wageningen University and Research Center Wageningen The Netherlands Food and Biobased Research Wageningen University and Research Center Wageningen The Netherlands

Pasteurella multocida hyaluronan synthase (PmhAS) is a bi-functional glycosyltransferase, containing a β1,3-glucuronyltransferase and β1,4-N-acetylglucosaminetransferase domain. PmhAS catalyzes the elongation of hyaluronan (hA) through the sequential addition of single monosaccharides to the non-reducing end of the hyaluronan chain. Research is focused on the relation between the length of the hA oligosaccharide and the single-step elongation kinetics from hA4 up to hA9. It was found that the turnover number kcat increased with length to maximum values of 11 and 14 s-1 for NAc- and UA-transfer, respectively. Interestingly, the specificity constant kcat/Km increased with polymer length from hA5 to hA7 to a value of 44 mm-1s-1, indicating an oligosaccharide binding site with increasing specificity towards a heptasaccharide at the UA domain. The value of kcat/Km remained moderately constant around 8 mm-1s-1 for hA4, hA6, and hA8, indicating a binding site with significantly lower binding specificity at the NAc domain than at the UA domain. These findings are further corroborated by a structural homology model of PmhAS, revealing two distinct sites for binding of oligosaccharides of different sizes, one in each transferase domain. Structural alignment studies between PmhAS and glycosyltransferases of the GT-A fold showed significant similarity in the binding of the UDP-sugars and the orientation of the acceptor substrate. These similarities in substrate orientation in the active site and in essential amino acid residues involved in substrate binding were utilized to localize the two hA oligosaccharide binding sites.

关键词： Pasteurella hyaluronan Binding Site Polymerization Co-Polymers

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在高性能轮胎配方中炭黑的加工性能与胶料性能

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合成橡胶工业 1990年第S1期13卷 264-269页

作者： J.m.Funt C.h.Shieh 杨俊平 Cabot Corporation USA USA

采用响应曲面分类研究法(RSm)确定在ESBR/顺式-1,4顺丁橡胶并用体中,炭黑表面积、炭黑用量及油用量三者各自或相互之间对胶料的加工性能、使用性能及炭黑的分散性能的影响,以说明它们在高性能乘用车轮胎中所具有的应用特征。当炭黑用... 详细信息

采用响应曲面分类研究法(RSm)确定在ESBR/顺式-1,4顺丁橡胶并用体中,炭黑表面积、炭黑用量及油用量三者各自或相互之间对胶料的加工性能、使用性能及炭黑的分散性能的影响,以说明它们在高性能乘用车轮胎中所具有的应用特征。当炭黑用量及其表面积减少、油用量增加时,炭黑混入胶料的速度增加。观察到,要使炭黑的分散性好,不一定需要有很快的炭黑混入速度。决定胶料拐弯稳定性的动态复合模量随炭黑用量及炭黑表面积增加而增加,动态损失模量的高低与此也有相似的规律。实验室抗湿和干滑性能随着炭黑用量的降低及油用量的增加而增加,这可能是由于橡胶与之接触的表面积增加之故。炭黑的CTAB表面积对抗滑性能几乎没有影响。实验室耐磨性能主要受炭黑用量及油用量的影响。在给定油用量的情况下,有一个可提供最高耐磨性的最佳炭黑用量。

关键词：炭黑表面积加工性能高性能轮胎结合橡胶量回归分析耐磨性胶料性能复合模量分散性损失模量

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A Novel Non Radioactive PCR-DNA Probe for the Detection of Aflatoxin Producing <i>Aspergillus</i>Species from major Food Crops Grown in India

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Advances in microbiology 2012年第4期2卷 577-586页

作者： S. R. Priyanka m. Venkata Ramana K. Balakrishna h. S. murali h. V. Batra Division of microbiology Defense Food Research Laboratory Siddarthanagar India

In the present study, a novel non radioactive digoxigenen labelled PCR-DNA probe was developed targeting nor-1 gene to assess the contamination of aflatoxigenic Aspergillus species in food grain samples from Southern parts of India. The sensitivity of developed PCR-DNA probe was determined to be 10 pg of genomic DNA and 1 pg of purified PCR product. The specificity of the DNA probe was validated by testing against an array of Aspergillus, Fusarium and Penicillium spp. A total of 89 Aspergillus isolates were recovered from 152 grain samples of maize, paddy, and groundnut. Among them, maize had the highest (90%) incidence of toxigenic Aspergillus species. When developed PCR-DNA probe was evaluated onto pure cultures of toxigenic and nontoxigenic Aspergillus species, 60 samples were positive for the nor-1 gene probe. DNA probe results unequivocally matched with the hPLC analysis. In conclusion, the novel PCR-DNA probe developed in this study may find its application in rapid detection of aflatoxin-producing Aspergillus isolates from contaminated cereal grains.

关键词： AFB1-Aflatoxin B1 hPLC-high Performance Liquid Chromatography NOR-1 Norsolorinic Acid Synthase PCR-Polymerase Chain Reaction

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Inductance and Capacitance of the multi Josephson Junction in Superconductor

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Journal of Applied mathematics and Physics 2018年第12期6卷 2544-2552页

作者： h. m. A. R. maruf m. R. Islam F.-U.-Z. Chowdhury Department of Physics Chittagong University of Engineering and Technology Chittagong Bangladesh Department of Physics University of Chittagong Chittagong Bangladesh

The characteristic behavior of the inductance and capacitance of multi junction ac Josephson effect in superconductor has been presented. Few parameters characterizing the behavior of Josephson junctions are needed to evaluate for technological applications. In this paper, the inductance and capacitance of the multi Josephson junction connected in parallel are evaluated, using simple classical argument. The numerical results for inductance and capacitance have also been included, indicating few technological applications.

关键词： Josephson Effects multi Josephson Junction Inductance Capacitance

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Luminescence and low temperature trap centers in mixed rare earth borate crystal

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Journal of Rare Earths 2018年第10期36卷 1024-1029页

作者： D.Joseph Danie Indra Raj Panday h.J.Kim Sunghwan Kim U.Fawad Department of Physics Kyungpook National University Department of Radiological Science Cheongju University Department of Physics Kohat University of Science and Technology

The single crystal of this compound has been grown from melt by using a conventional Czochralski technique. The temperature dependent luminescence spectra were measured using a 265 nm laser as an exciting source in the range of 10-300 K. The scintillation decay time profile was measured and found to have three components. The influence of the trap centers on the luminescence properties was studied by means of thermoluminescence（TL） glow peak analysis. Low temperature TL glow peaks were measured in the temperature range of 10-300 K at the heating rate of 0.1 K/s for X-ray irradiated sample. The TL glow peak consists of two dominant peaks at 88 and 109 K. Several glow peaks with a complex nature causes the decrease in the light yield at temperatures below 250 K, and along with long scintillation decay components were observed. The trap parameters such as activation energy（E）, frequency factor（s）and order of kinetics（b） were calculated using various standard methods such as peak shape（PS）,variable heating rate（VhR）, initial rise（IR） and computerized glow curve deconvolution（CGCD）.

关键词： Rare earth Decay time Thermoluminescence Kinetic parameters

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Effect of Nd^(3+) substitution on structural and magnetic properties of mg-Cd ferrites synthesized by microwave sintering technique

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Journal of Rare Earths 2018年第4期36卷 390-397页

作者： S.R.Bhongale h.R.Ingawale T.J.Shinde P.N.Vasambekar Department of Physics Yashavantrao Chavan Institute of Science Department of Physics B.V.M.B.S.K.Kanya Mahvidyalaya Department of Physics K.R.P.Kanya Mahvidyalaya Department of Electronics Shivaji University

Nd3＋ substituted spinel ferrites with formula mgxCd1-xNd0.03Fe1.97O4（x = 0.0.2,0.4,0.***.0.8 and 1.0）were prepared by oxalate co-precipitation method using novel microwave sintering technique. AR grade sulphates were used as starting chemicals. The samples were sintered at optimized power of 70 W for10 min in a microwave oven（800 W）. The structural analysis of these samples was done by using X-ray diffraction, scanning electron microscope and Fourier transform IR techniques. The XRD analysis of the synthesized ferrite confirms the formation of cubic spinel structure of ferrite. The influence of Nd3＋substitution on various structural parameters of mg-Cd ferrites was reported. IR study indicates the spectra contain two intense absorption bands around 600 and 400 cm^（-1） in addition with four extra bands. The magnetic properties of all ferrites were studied by using a vibration sample *** crystallite and grain size dependant magnetic properties are observed. The composition mg_（0.6）Cd_（0.4）Nd_（0.03）Fe_（1.97）O_4 has better magnetic properties that can be used in recording media. The fast synthesis of spinel ferrites is yielded due to use of the microwave sintering technique.

关键词： mg-Nd-Cd ferrite Rare earth microwave sintering IR study Coercive force

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FRACTAL RESEARCh ON CRACKS PROPAGATION OF GAS PIPELINE X52 STEEL WELDING LINE UNDER hYDROGEN ENVIRONmENT

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Acta metallurgica Sinica(English Letters) 2001年第3期14卷 219-226页

作者： S.h. Dong , Y.m. Lu, Y. Zhang and Q. Wu (mechanics Electronic Department, University of Petroleum, Beijing 102200, China) (Department of material Physics, University of Science and Technology Beijing, Beijing 100083, China) (Yan Shan University, Qinhuangd Dept. of mech. Electron. Univ. of Pet. Beijing 102200 China

Based on the theory of hydrogen enhanced localized plasticity of the hydrogen induced cracking and the consideration of the effect of the residual stress produced by eliminated stress heat-treatment, a fractal model of hydrogen induced cracking was presented, and the relationships among the effective surface energy (h), fractal dimension D and stress intensity factor of hydrogen induced cracking, KIh, for welding pipeline under hydrogen environment was set up, from which the relationship of D and KISCC was obtained. The model has been verified experimentally to be correct.

关键词： Crack initiation Electric arc welding Environmental impact Fractals hydrogen

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3D T2WI缩短多参数前列腺mRI的扫描方案

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国际医学放射学杂志 2018年第3期 371-372页

作者： h.Polanec m.Lazar G.J.Wengert h.Bickel C.Spick m.Susani 王姗姗 Department of Biomedical Imaging and Image-Guided Therapy Medical University of Vienna

摘要目的验证3 T mR前列腺的3D T2W能否获得与2D T2W一致的影像质量、病灶呈现质量及第2版前列腺影像报告和数据系统(PI-RADS)的表现评估。方法该项由伦

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EFFECTS OF SEED DENSITY AND QUALITY OF WhEAT CULTIVARS ON GROWTh AND DEVELOPmENT OF WEEDS

EFFECTS OF SEED DENSITY AND QUALITY OF WHEAT CULTIVARS ON GR...

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The ⅩⅤth International Plant Protection Congress

作者： m.h.GhARINEh K.GhASSEmI A.BAKhShANDEh A.JAVANShIR m.VALIZADEh Crop Production Department Ramin Agricultural Education ＆ Research Faculty Shahid Chamran University Ahwaz Iran Crop Production Department Ramin Agricultural Education ＆ Research Faculty Shahid Chamran University Ahwaz Iran Crop Production Department Ramin Agricultural Education ＆ Research Faculty Shahid Chamran University Ahwaz Iran Crop Production Department Ramin Agricultural Education ＆ Research Faculty Shahid Chamran University Ahwaz Iran Crop Production Department Ramin Agricultural Education ＆ Research Faculty Shahid Chamran University Ahwaz Iran

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Impact of Post hepatitis C Chronic Liver Disease and hepatocellular Carcinoma on health Related Quality of Life

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Advances in Aging Research 2015年第6期4卷 177-186页

作者： Somaia m. Ebeid Safaa h. Ali heba Y. Kamel Ahmed A. Elbaz hazem m. El-hariri Departments of Geriatric medicine Faculty of Medicine Ain Shams University Cairo Egypt Departments of Tropical medicine Faculty of Medicine Ain Shams University Cairo Egypt Department of Community medicine Research National Research Center Cairo Egypt

Background: Post hepatitis C virus chronic liver disease (CLD) is prevalent among the Egyptian population with a bad impact upon their quality of life (QOL). hepatocellular carcinoma (hCC) is one of the long term and fatal complications of CLD and it also has its negative impact on patient’s quality of life. Aim: To assess impact of CLD and hCC on the quality of life of group of hospitalized elderly patients. methodology: Ninety elderly patients were divided into three groups: 30 elderly with post hepatitis C virus CLD, 30 elderly with hCC and 30 others free of liver disease as control group (Cn), all were recruited from the in-patient ward and the outpatient clinic of the Geriatric Department, Ain-Shams University hospital. After giving consent, comprehensive geriatric assessment was done with assessment of their quality of life by using the Short Form-36 health survey (SF-36). Investigations including liver enzymes, serum albumin, serum bilirubin and abdominal ultrasound were done. Results: All QOL domains were the highest among control group, followed by hCC group and the least among CLD group. The differences were statistically significant in most subscales and total score [mean of Cn = 81.9 ± 12.4, mean of CLD = 47.5 ± 21.9, mean of hCC = 62.3 ± 16.1;P Cn/CLD ≤ 0.001, P Cn/hCC ≤ 0.001, P CLD/hCC = 0.004]. Albumin was the only biochemical marker correlated positively with total SF score and two subscales (PF and EF) [r = 0.408;P = 0.025]. Conclusion & Recommendation: Our study showed a decrease in the QOL of Egyptian post hepatitis C virus CLD and hCC patients compared with Egyptian population norms. The results showed that CLD were more affected than hCC patients. This had a particularly serious negative impact on their life. The findings indicate a need for updated counseling and educational materials designed to provide adequate information and consistent healthcare service to this patient setting.

关键词： Post hepatitis C Virus Chronic Liver Diseases hepatocellular Carcinoma Quality of Life Short Form-36 health Survey

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