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Assessing phylogenetic relationships of Lycium samples using RAPD and entropy theory

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Acta Pharmacologica Sinica 2005年第10期26卷 1217-1224页

作者： Ricky ns WONG Amber WY HA Department of Biology Hong Kong Baptist University Hong Kong China Department of Biology Hong Kong Baptist University Hong Kong China

Aim: To evaluate the phylogenetic relationships among related species of Lycium samples. Methods: Random amplified polymorphic DNA (RAPD) fingerprinting and lab-on-a-chip electrophoresis techniques were used to analyze the characteristics of Lycium species. Seven species and 3 varieties of Lycium were studied. Based on RAPD fingerprint data obtained from 11 primers, we proposed a new index, called dispersivity, using entropy theory and projection methods to depict the diversity of the DNA fingerprints. Results: Using the proposed dispersivity, primers were sorted and the dendrograms of the 7 species and 3 varieties of Lycium were constructed synthetically by merging primer information. Conclusion:Phylogenetic relationships among Lycium samples were constructed synthetically based on RAPD fingerprint data generated from 11 primers.

关键词： DNA fingerprinting RAPD technique lab-on-a-chip entropy UPGMA

Microstructure Variation of Cold Deformed MP159 Alloy during Aging

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Journal of Materials Science & Technology 1996年第2期12卷 109-113页

作者： Han, GW feng, D Yin, M Yang, ns Central Iron and Steel Research Institute Beijing 100081 China

By comparing the relationship of room temperature yield strength with the reduction of cold rolled MP159 alloy before and after aging at 650 degrees C, and by means of TEM examination on the corresponding microstructures, the occurrence of fcc(alpha)-->hcp(epsilon) martensitic transition in MP159 alloy during cold deformation and the variation of the platelet epsilon phase during aging have been studied. The results show that the platelet a phase is really formed when the cold deformation reaches a critical value, and both the amount and the width of the platelet epsilon phase would further increase during 650 degrees C aging. The increases of the amount and the width of the platelet epsilon phase result in an additional increase of yield strength. Therefore, it is concluded that the additional hardening effect of MP159 alloy after aging is not only from the precipitation of Ni(3)X disperse phase but also from the volume fraction increase of the platelet epsilon phase. further occurrence of the martensitic transition during aging may be due to the elimination of residual compression stress within matrix induced by the fcc(alpha)-->hcp(epsilon) transition during cold deformation.

关键词： Cobalt alloys

An Approximate Riemann Solver for Advection-Diffusion Based on the Generalized Riemann Problem

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Communications on Applied Mathematics and Computation 2020年第3期2卷 515-539页

作者： Steven Jöns Claus-Dieter Munz Institute of Aerodynamics and Gas Dynamics University of StuttgartPfafenwaldring 2170569 StuttgartGermany

We construct an approximate Riemann solver for scalar advection-diffusion equations with piecewise polynomial initial *** objective is to handle advection and diffusion simultaneously to reduce the inherent numerical diffusion produced by the usual advection flux *** approximate solution is based on the weak formulation of the Riemann problem and is solved within a space-time discontinuous Galerkin approach with two *** novel generalized Riemann solver produces piecewise polynomial solutions of the Riemann *** conjunction with a recovery polynomial,the Riemann solver is then applied to define the numerical flux within a finite volume *** results for a piecewise linear and a piecewise parabolic approximation are *** results indicate a reduction in numerical dissipation compared with the conventional separated flux calculation of advection and ***,it is shown that using the proposed solver only in the vicinity of discontinuities gives way to an accurate and efficient finite volume scheme.

关键词： Generalized Riemann problem Advection-diffusion Discontinuous Galerkin Numerical flux ADER Diffusive generalized Riemann problem Space-time solution Recovery method

Intensity correction in all-sky auroral image projection transform

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Chinese Science Bulletin 1997年第8期42卷 700-703页

作者： Yang, YG Liu, RY Sato, ns Polar Research Institute of China Shanghai China National Institute of Polar Research Tokyo Japan

BY using all-sky(fish-eye)lens and highly sensitive TV camera,the effective monitoring ra-dius and time resolution of ground aurora observation have now been raised to 600 km and1/30 s(for instance,SIT-TV camera recording in NTSC format).By incorporating high-sen-sitivity imaging device(integrated from image intensifier and CCD(charge coupled device)

关键词： All-sky auroral image projection transtorm intensity correction.

An optical device to homogenize a laser beam

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Chinese Optics Letters 2005年第12期3卷 698-700页

作者：李重光李俊昌 Agèns Delmas Institute of Applied Laser Kunming University of Science and TechnologyKunming 650093 CETHIL UMR 5008 InsA de Lyon Batiment S.Carnot 20 Avenue Albert Einstein 69621 Villeurbanne CedexFrance

Based on segmentation-recombination principle, a specific optical device is designed to homogenize a highpower CO2 laser beam which is used as a heating source. A model is developed to simulate the intensity distribution of converted laser beam. The results show that the theoretical simulation is consistent with experimental record. The uniformity of converted beam spot is discussed. After modifying the optical parameters of current device, a new optical system is given, through which the uniformity of shaped beam spot is improved remarkably.

关键词： CO optical fig

Paoayensis aquatica ***.(Ascomycetes)on submerged wood from the River Tapti,Maharashtra,India

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Studies in fungi 2019年第1期4卷 50-53页

作者： Borse BD Pawar ns N.S.S.Dhule’s U.P.Arts and Science College DahiwelDhuleM.S. S.S.V.P.S.Dhule’s Arts Com.and Sci.CollegeSindkhedaDhuleM.S.

A new fungus was collected on submerged wood from a freshwater stream in Maharashtra at Western Ghats is described here as *** new ascomycete fungus differs from the type and only species in the genus,***,by size and ... 详细信息

关键词： biodiversity freshwater systematic taxonomy

PD-1 induction through TCR activation is partially regulated by endogenous TGf-β

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Cellular & Molecular Immunology 2015年第5期12卷 648-649页

作者： Raja Rekik Nadia Belhadj Hmida Ahlem Ben Hmid Imen Zamali ns Kammoun Melika Ben Ahmed Laboratory of Transmission Control and Immunobiology of Infection Institut Pasteur de Tunis Tunis Tunisia Laboratory of Clinical Immunology Institut Pasteur de Tunis Tunis Tunisia faculte de Medecine de Tunis Universite Tunis El Manar Tunis Tunisia

The programmed death 1 （PD-1） pathway is a way of inhibiting T-cell proliferation and cytokine production. This pathway is important for maintaining peripheral tolerance. Different mechanisms and cytokines are involved in this pathway. Herein, we show the contribution of endogenous TGf-β to increasing PD-1 expression after T cell receptor （TCR） activation.

关键词： TGf-β 内源性 TCR 诱导活化细胞因子 T细胞增殖 T细胞受体

Band-pass filtered velocity statistics in decaying turbulent box

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Theoretical & Applied Mechanics Letters 2011年第4期1卷 40-44页

作者： J.M.Lenoir S.Simoёns Jean-Noel Gence UMR CNRS 5509 LMFAECLUCB LyonIINSALyon.France

for homogeneous isotropic turbulence study,the acquisition of band-pass filtered velocity increments(fVI) in a non-forced turbulent box is still a challenge both experimentally and *** and associated physical processes,at a given instant,are permanently contaminated by a forcing process which can seldom be *** situation tends to be the origin of intermittency and the non-Gaussian probability density distribution for acceleration and velocity *** reveal implied mechanism,grid turbulence is adapted to observe non-perturbed homogeneous isotropic *** velocity increments(VI) can be obtained following Comte-Bellot and Corrsin(GCBC) by means of two point-two time shifted velocity *** is difficult to obtain decaying turbulence(DT) at large turbulent Reynolds number without pollution coming from *** it is also significant to investigate DT in low Reynolds number regimes to determine non-polluted *** similarity of DT between particle image velocimetry(PIV) and hot wire anemometry measurements by GCBC are *** we focus our tendency on VI and fVI probability density function(PDf) shapes in this *** conclusion,the tendency to Gaussian shape in inertial zone wavenumbers,demonstrates that there will be no intermittency if turbulent cascade is not perturbed.

关键词： velocity increment velocity inertial zone homogeneous turbulence PDf shape

Hepatogenic differentiation of human mesenchymal stem cells from adipose tissue in comparison with bone marrow mesenchymal stem cells

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World Journal of Gastroenterology 2006年第36期12卷 5834-5845页

作者： Raquel Taléns-Visconti Ana Bonora Ramiro Jover Vicente Mirabet francisco Carbonell José Vicente Castell María José Gómez-Lechón Unidad de Hepatología Experimental Centro de Investigación Hospital La Fe Valencia Spain Departamento de Bioquímica y Biología Molecular Universidad de Valencia Valencia Spain. Unidad de Hepatología Experimental Centro de Investigación Hospital La Fe Valencia Spain Centro de Transfusión de la Comunidad Valenciana Generalidad ValencianaValencia Spain Unidad de Hepatología Experimental Centro de Investigación Hospital La Fe Valencia.Spain. Departamento de Bioquímica y Biología Molecular Universidad de Valencia Valencia Spain Unidad de Hepatología Experi-mental Centro de Investigación Hospital La Fe Valencia Spain

AIM： To investigate and compare the hepatogenic transdifferentiation of adipose tissue-derived stem cells （ADSC） and bone marrow-derived mesenchymal stem cells （BMSC） in vitro. Transdifferentiation of BMSC into hepatic cells in vivo has been described. Adipose tissue represents an accessible source of ADSC, with similar characteristics to BMSC. METHODS： BMSCs were obtained from patients undergoing total hip arthroplasty and ADSC from human adipose tissue obtained from lipectomy. Cells were grown in medium containing 15% human serum. Cultures were serum deprived for 2 d before cultivating under similar pro-hepatogenic conditions to those of liver development using a 2-step protocol with sequential addition of growth factors, cytokines and hormones. Hepatic differentiation was RT-PCR-assessed and liver-marker genes were immunohistochemically ***： BMSC and ADSC exhibited a fibroblastic morphology that changed to a polygonal shape when cells differentiated. Expression of stem cell marker Thyl decreased in differentiated ADSC and BMSC. However, the expression of the hepatic markers, albumin and CYPs increased to a similar extent in differentiated BMSC and ADSC. Hepatic gene activation could be attributed to increased liver-enriched transcription factors （C/EBPβ and HNf4α）, as demonstrated by adenoviral expression ***： Mesenchymal stem cells can be induced to hepatogenic transdifferentiation in vitro. ADSCs have a similar hepatogenic differentiation potential to BMSC, but a longer culture period and higher proliferation capacity. Therefore, adipose tissue may be an ideal source of large amounts of autologous stem cells, and may become an alternative for hepatocyte regeneration, liver cell transplantation or preclinical drug testing.

关键词： Mesenchymal stem cells Bone marrow Adipose tissue Transdifferentiation Hepatic lineage Liver cell transplantation.