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Synthesis and Characterization of Tl-1223 Substituted by Scandium

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Journal of Materials Science & Technology 2013年第11期29卷 1079-1084页

作者： R.Awad A.Al-Zein M.Roumie I.h.Ibrahim Physics Department Faculty of ScienceAlexandria University Laboratoire Structures Proprietes et Modelisation des Solides(SPMS) Physics Department Faculty of ScienceBeirut Arab University Accelerator Laboratory Lebanese Atomic Energy Commission

X-ray powder diffraction, scanning electron microscopy （SEM）, energy dispersive X-ray, electrical resistivity and AC-magnetic susceptibility measurements have been performed for polycrystalline superconducting samples of type TIBa2Ca2_xSCxCu309_δ （0.0 ≤ x 〈 0.6）. The powder X-ray diffractograms indicate that the tetragonal structure of T1-1223 is not affected by Sc-substitution whereas the lattice parameters are changed. The X-ray analysis indicates that the low-contents of scandium （x） enhance the formation of T1-1223 and reduce the secondary phases. The grain-size determined by SEM decreases as x increases. The electrical resistivity measurements show suppression in the superconducting transition temperature, Tc, and an increase in both the residual resistivity and the superconducting transition width as x increases. The suppression in Tc is attributed to the hole-filling mechanism.

关键词： X-ray diffraction Resistivity Superconducting transition temperature AC magnetic susceptibility

Post-transcriptional regulation of vascular endothelial growth factor: Implications for tumor angiogenesis

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World Journal of Gastroenterology 2006年第31期12卷 4937-4942页

作者： Peter S Yoo Abby L Mulkeen Charles h Cha Gastrointestinal Surgery and Surgical OncologyYale School of Medicine New HavenConnecticutUnited States

Vascular endothelial growth factor （VEGF） is a potent secreted mitogen critical for physiologic and tumor angiogenesis. Regulation of VEGF occurs at several levels, including transcription, mRNA stabilization, translation, and differential cellular localization of various isoforms. Recent advances in our understanding of post-transcriptional regulation of VEGF include identification of the stabilizing mRNA binding protein, huR, and the discovery of internal ribosomal entry sites in the 5＇uTR of the VEGF mRNA. Monoclonal anti-VEGF antibody was recently approved for use in humans, but suffers from the need for high systemic doses. RNA interference （RNAi） technology is being used in vitro and in animal models with promising results. here, we review the literature on post-transcriptional regulation of VEGF and describe recent progress in targeting these mechanisms for therapeutic benefit.

关键词： Vascular endothelial growth factor Vascular endothelial growth hormone Post-transcriptional regulation mRNA stability huR ELAVl Internal ribosomal entry IRES siRNA RNAi Bevacizumab

Labelling of a pyrazole derivative with ^(131)I and investigation of its radiopharmaceutical potential

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Chinese Science Bulletin 2013年第24期58卷 2964-2969页

作者： KuRTDEDE Esra BILDIRICI Ishak ENGINAR hüseyin SENER Ahmet Department of Chemistry Faculty of Arts and Sciences Afyon Kocatepe University Department of Chemistry Faculty of Arts and Sciences Yuzuncu Yil University

We investigated the radiolabeling efficiency, in vitro stability, and biodistribution of radioactive iodine (131I)-labeled 4-benzoyl-1-(4-carboxyphenyl)-5-phenyl-1h-pyrazole-3-carboxylic acid (P3CA). A quality-control study of the labeled substance ( 131I-P3CA) was conducted using electrophoresis and radio thin-layer chromatography (RTLC). Biodistribution studies were undertaken in 9 female albino Wistar rats. Rats were killed at various times (15, 60 and 180 min), their organs removed, and percentage of injected dose per gram (ID%/g) values calculated. The labeling yield of P3CA was 97.08%±0.80%. The maximum uptake of 131I-P3CA was seen in the lungs, stomach and spleen at 15 min. The uptake of labeled compound decreased over time in the lungs, whereas that in the stomach decreased. These data suggest that 131I-P3CA had high binding efficiency, high uptake in the lung, and sufficient stability to be used in diagnostic studies.

关键词：吡唑衍生物放射性药物 Wistar大鼠放射性标记体外稳定性标签羧基苯基放射性碘

Clinical relevance of cancer genome sequencing

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World Journal of Gastroenterology 2013年第13期19卷 2011-2018页

作者： Chee Seng Ku David N Cooper Dimitrios h Roukos Department of Medical Epidemiology and Biostatistics Karolinska Institute Institute of Medical Genetics School of MedicineCardiff University Department of Surgery Ioannina University School of Medicine Centre for Biosystems and Synthetic Genomic Network Medicine Centre for BioSystems and Genomic Network MedicineIoannina University

The arrival of both high-throughput and bench-top next-generation sequencing technologies and sequence enrichment methods has revolutionized our approach to dissecting the genetic basis of cancer. These technologies have been almost invariably employed in wholegenome sequencing (WGS) and whole-exome sequencing (WES) studies. Both WGS and WES approaches have been widely applied to interrogate the somatic mutational landscape of sporadic cancers and identify novel germline mutations underlying familial cancer syndromes. The clinical implications of cancer genome sequencing have become increasingly clear, for example in diagnostics. In this editorial, we present these advances in the context of research discovery and discuss both the clinical relevance of cancer genome sequencing and the challenges associated with the adoption of these genomic technologies in a clinical setting.

关键词： Next-generation sequencing Exome Cancer Diagnostics Familial cancer syndrome Somatic mutation

Evaluating the Origin Intensity Factor in the Singular Boundary Method for Three-Dimensional Dirichlet Problems

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Advances in Applied Mathematics and Mechanics 2017年第6期9卷 1289-1311页

作者： Linlin Sun Wen Chen Alexander h-D.Cheng State Key Laboratory of hydrology-Water Resources and hydraulic Engineering International Center for Simulation Software in Engineering and SciencesCollege of Mechanics and MaterialsHohai UniversityNanjing 210098China Department of Computational Science and Statistics School of ScienceNantong UniversityNantongJiangsu 226019China School of Engineering University of MississippiUniversityMS 38677USA

In this paper,a new formulation is proposed to evaluate the origin intensity factors(OIFs)in the singular boundary method(SBM)for solving 3D potential problems with Dirichlet boundary *** SBM is a strong-form boundary discretization collocation technique and is mathematically simple,easy-to-program,and free of *** crucial step in the implementation of the SBM is to determine the OIFs which isolate the singularities of the fundamental ***,the inverse interpolation technique(IIT)is adopted to calculate the OIFs on Dirichlet boundary,which is time consuming for large-scale *** recent years,the new methodology has been developed to efficiently calculate the OIFs on Neumann boundary,but the Dirichlet problem remains an open *** study employs the subtracting and adding-back technique based on the integration of the fundamental solution over the whole boundary to develop a new formulation of the OIFs on 3D Dirichlet *** problems with varied domain shapes and boundary conditions are carried out to validate the effectiveness and feasibility of the proposed scheme in comparison with the SBM based on inverse interpolation technique,the method of fundamental solutions,and the boundary element method.

关键词： Origin intensity factors singular boundarymethod boundary-typemeshlessmethod potential problem fundamental solution

Elastic Constants of Nickel Oxide

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Chinese Physics Letters 1991年第3期8卷 153-156页

作者： WANG Jifang FIShER,E.S. M.h.Manghnzmi Institute of Physics Academia SinicaBeijing 100080 Argonne National Laboratory ArgonneIllinoisUSA hawaii Institute of Geophysics University of HawaiiHonoluluHawaiiUSA

Previous measurements of the single crystal elastic constants of NiO by ultrasonic techniques have been in wide *** paper gives the results of recent data obtained from several well characterized NiO single *** present results for the antiferromagnetic phase at 298K are different from the previous data and rectify certain questions about the elastic anisotropy ratio C_(44)/C'and bulk modulus K_(s).

关键词： crystals Elastic modulus

EFFECT OF DEEP COLD TREATMENT ON TWO CASE hARDENING STEELS

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 1-7页

作者： C.h.Surberg P.Stratton K.Lingenhle V-Research Center of Competence for Tribology and Technical Logistics Gmbh DornbirnAustriap The Linde Group UnterschleiβheimGermany Lingenhle Technology Gmbh FeldkirchAustria

Although cold treatments have been used to reduce the retained austenite in the cases of carburised steel for many years, there is little data on deep cold temperatures below -70℃ or treatment times longer than an hour or two. This study set out to determine the effects of such deep cold treatments at temperatures -150℃ for 24 h. The study investigated the effects of deep cold on the microstructure, hardness profile, residual stress and internal oxidation on two typical carburising steels, 16MnCr5 and 21NiCrMo2. The study found that for both 16MnCr5 and 21NiCrMo2 carburised to a case depth of approximately 0.8 mm, the longer and colder the deep cold treatment, the more the austenite retained in the case was converted to martensite and the harder it became. After low temperature tempering, the hardness difference was smaller, but still significant. In both steels, the case appeared more refined and homogeneous after deep cold treatment. Deep cold treatment had a negligible effect on the core properties of either steel.

关键词： Carburised steel Deep cold Retained austenite

Interaction specific binding hotspots in Endonuclease colicin-immunity protein complex from MD simulations

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Science China Chemistry 2013年第8期56卷 1143-1151页

作者： YAO XueXia JI ChangGe XIE DaiQian ZhANG John Z.h. School of Chemistry and Chemical Engineering Nanjing University College of Engineering Nanjing Agricultural University State Key Laboratory of Precision Spectroscopy Department of PhysicsEast China Normal University Department of Chemistry New York University

The binding of Endonuclease colicin 9 (E9) by Immunity protein 9 (Im9) was found to involve some hotspots from helix III of Im9 on protein-protein interface that contribute the dominant binding energy to the *** the current work,MD simulations of the WT and three hotspot mutants (D51A,Y54A and Y55A of Im9) of the E9-Im9 complexes were carried out to investigate specific interaction mechanisms of these three hotspot *** changes of binding energy between the WT and mutants of the complex were computed by the MM/PBSA method using a polarized force field and were in excellent agreement with experiment values,verifying that these three residues were indeed hotspots of the binding *** decomposition analysis revealed that binding by D51 to E9 was dominated by electrostatic interaction due to the presence of the carboxyl group of Asp51 which hydrogen bonds to *** binding by hotspots Y54 and Y55,van der Waals interaction from the aromatic side chain of tyrosine provided the dominant *** comparison,calculation by using the standard (nonpolarizable) AMBER99SB force field produced binding energy changes from these mutations in opposite direction to the experimental *** hydrogen bond analysis showed that conformations sampled from MD simulation in the standard AMBER force field were distorted from the native state and they disrupted the inter-protein hydrogen bond network of the protein-protein *** current work further demonstrated that electrostatic polarization plays a critical role in modulating protein-protein binding.

关键词： protein-protein interaction binding hotspot mutation Endonuclease Colicin immunity protein MD simulation

Semisolid joining of aluminum A356 alloy by partial remelting and mechanical stirring

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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1792-1798页

作者： S.M.J.ALVANI h.AAShuRI A.KOKABI R.BEYGI Materials Science and Engineering Department Sharif University of Technology

A method to reach the globular weld structure of A356 aluminum alloy using stirring the localized semisolid zone during butt-joining is *** the heat conductivity of this alloy is very high, the accurate controlling of temperature during joining must be considered.A gas heating system was used to heat up the nitrogen gas up to the required temperature.A dried and free oxygen gas was prepared when a stream of nitrogen gas could pass closely around a hot *** and pure nitrogen gas flow through a precise ceramic nozzle was used to create a localized semisolid *** this stage a fine stirrer was introduced into the weld seam in order to mix the two sides into a single uniform *** were moved in direction of joint line by a small trolley to avoid the deviation of nozzle from the joint line and its distance and angle from the substrate.A fixture system was used to hold two substrates together on the trolley.A narrow hot plate was located on the trolley to heat up the joint line due to high heat conductivity of *** of gas temperature was investigated on the microstructure and mechanical properties of weld *** showed that increase in temperature promoted the final welding properties, and also at liquid fractions less than 50% joining was not fully *** best mechanical properties were achieved with liquid fraction of about 70%.

关键词： semisolid joining A356 localized stirring shear punch semi-solid holding thermal treatment