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Comparison of effects of Mechanical Stretching on Osteogenic Potential of ASCs and BMSCs

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Bone Research 2013年第3期1卷 282-290页

作者： Brian e. Grottkau Xingmei yang Liang Zhang Ling Ye Yunfeng Lin Department of Orthopaedic Surgery MassGeneral Hospital for Children and the Pediatric Orthopaedic Laboratory for Tissue Engineering and Regenerative Medicine Harvard Medical SchoolBoston Massachusetts USA State Key Laboratory of Oral Diseases West China Hospital of Stomatology Sichuan University

Mechanical forces play critical roles in the development and remodeling processes of bone. As an alternative cell source for bone engineering, adipose-derived stem cells （ASCs） should be fully investigated for their responses to mechanical stress. Similarly, the osteogenic potential, stimulated by mechanical stress, should be compared with bone marrow stromal cells （BMSCs）, which have been clinically used for bone tissue engineering. In this study, ASCs and BMSCs were osteogenic-induced for 48 hours, and then subjected to uniaxial mechanical stretching for 2 or 6 hours. Cell orientation, osteogenic regulatory genes, osteogenic genes and ALP activities were measured and compared between ASCs and BMSCs. ASCs could align in a perpendicular way to the direction of stretching stress, while BMSCs did not present a specific alignment. Both 2 and 6 hours mechanical stretching could enhance the mRNA expression of Osx and Runx2 in BMSCs and ASCs, while OCN mRNA only increased in ASCs after 6 hours mechanical loading. Mechanical stretching enhanced the BMP-2 mRNA expression in ASCs, while only after 6 hours of mechanical loading significantly increased the BMP-2 gene expression in BMSCs. Significant differences only exist between ASCs and BMSCs loaded at 2 hours of mechanical stretching. It is concluded that ASCs are more rapid responders to mechanical stress, and have greater potential than BMSCs in osteogenesis when stimulated by mechanical stretching, indicating their usefulness for bone study in a rat model.

关键词： mechanotransduction stem cells osteoblasts adipocytes

High gene flows promote close genetic relationship among finewool sheep populations(Ovis aries) in China

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Journal of Integrative Agriculture 2016年第4期15卷 862-871页

作者： HAN Ji-long yang Min GUO Ting-ting LIU Jian-bin NIU Chun-e YUAN Chao YUe Yao-jing yang Bo-hui Lanzhou Institute of Husbandry and Pharmaceutical Sciences Chinese Academy of Agricultural Sciences Lanzhou 730050 P. R. China Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing 100193 P.R. China

The aim of our present study was to construct genetic structure and relationships among Chinese fine-wool sheep breeds. 46 individuals from 25 breeds or strains were genotyped based on the Illumina Ovine 50K SNP array. Meanwhile, genetic variations among 482 individuals from 9 populations were genotyped with 10 microsatellites. In this study, we found high genetic polymorphisms for the microsatellites, while 7 loci in the Chinese superfine Merino strain （Xinjiang types）（CMS） and 5 loci in Gansu alpine superfine-wool sheep strain （GSS） groups were found deviated from Hardy-Weinberg equilibrium （HWe）. Genetic drift FsT=0.019 （P〈0.001） and high gene flows were detected in all the 7 fine-wool sheep populations. Phylogenetic analysis showed fine-wool sheep populations were clustered in a group independent from the Chinese indigenous breeds such that the 7 fine-wool sheep clustered distinct from Liangshan semifine-wool sheep （LS） and Hu sheep （HY） reflected by different population differentiation analyses. Overall, our findings suggested that all fine-wool sheep populations have close genetic relationship, which is consistent with their breeding progress. These populations, therefore, can be regarded as open-breeding populations with high levels of gene flows. Furthermore, the two superfine-wool strains, viz., CMS and GSS, might be formed by strong artificial selection and with frequent introduction of Australian Merino. Our results can assist in breeding of superfine-wool sheep and provide guidance for the cultivation of new fine-wool sheep breeds with different breeding objectives.

关键词： Chinese fine-wool sheep indigenous sheep breeds genetic relationship gene flow microsatellites

Treatment of PC-3 cells with ultrasound combined with microbubbles induces distinct alterations in the expression of Bcl-2 and Bax

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Chinese Science Bulletin 2013年第28期58卷 3535-3540页

作者： BAI WenKun yang ShaoLing SHeN e ZHANG JiZhen SHeN ZhiYong HU Bing Shanghai Jiao Tong University Affiliated 6th People's Hospital Shanghai Institute of Ultrasound in Medicine

The objective of the present study was to investigate whether ultrasound combined with microbubbles induces apoptotic cell death in androgen-independent prostate cancer cells and to identify the probable *** used ultrasound in continuous wave mode with a frequency of 21 kHz and a spatial-average temporal-average intensity of 46 mW/*** combined with microbubbles(200μL SonoVue)was used to treat androgen-independent human prostate cancer PC-3 cells for 30 ***-3 cells were divided into three groups:the control group,the ultrasound group and the ultrasound combined with microbubbles *** after treatment,trypan blue exclusion was used to assess cell *** apoptosis at 24 h after treatment was measured using transmission electron microscopy and flow *** blotting was used to evaluate the expression of the apoptosis-related proteins,Bcl-2 and *** combined with microbubbles had a minimal effect on the viability of PC-3cells and induced minimal levels of cell *** level of apoptosis in PC-3 cells induced by this modality was significantly higher than in controls(12.77±0.31%vs.2.56±0.22%,Peatment with ultrasound combined with microbubbles increased the expression of Bax,a pro-apoptotic protein,and decreased the expression of Bcl-2,an anti-apoptotic *** was concluded that ultrasound combined with microbubbles induces apoptotic cell death in human prostate cancer PC-3 cells through down-regulation of Bcl-2 and up-regulation of Bax.

关键词：超声波频率 Bcl-2 细胞死亡结合治疗 Bax 微泡诱导 Western印迹法

STABILITY OF HLPPS AND MODIFIeD HLPPS POLICIeS FOR THe Re-eNTRANT LINe

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Journal of Systems Science & Complexity 2010年第6期23卷 1239-1246页

作者： Jiankui yang School of Science Beijing University of Posts and Telecommunications Beijing 100876 China.

For a re-entrant line operating under the HLPPS service policy, the stability was proved by Bramson in 1996. A simple proof for the stability of the fluid model is given here. Also, the HLPPS service policy is modified according to the proportion of potential jobs and the stability of the fluid model under the modified one is proved.

关键词： Fluid model re-entrant line stability.

Fast PARAFAC decomposition with application to polarization sensitive array parameter estimations

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Journal of Systems engineering and electronics 2018年第4期29卷 714-722页

作者： LI yang The 10th Research Institute China Electronics Technology Group Corporation

In tensor theory, the parallel factorization （PARAFAC）decomposition expresses a tensor as the sum of a set of rank-1tensors. By carrying out this numerical decomposition, mixedsources can be separated or unknown system parameters can beidentified, which is the so-called blind source separation or blindidentification. In this paper we propose a numerical PARAFACdecomposition algorithm. Compared to traditional algorithms, wespeed up the decomposition in several aspects, i.e., search di-rection by extrapolation, suboptimal step size by Gauss-Newtonapproximation, and linear search by n steps. The algorithm is ap-plied to polarization sensitive array parameter estimation to showits usefulness. Simulations verify the correctness and performanceof the proposed numerical techniques.

关键词： tensor decomposition parallel factorization(PARAFAC) alternating least squares (ALS) polarization sensi-tive array (PSA)

Near-earth asteroid flyby trajectories from the Sun-earth L2 for Chang’e-2’s extended flight

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Acta Mechanica Sinica 2013年第1期29卷 123-131页

作者： yang Gao State Key Laboratory of Astronautic Dynamics engineering and Technology Center for Space Utilization Chinese Academy of Sciences

Driven by curiosity about possible flight options for the Chang＇e-2 spacecraft after it remains at the Sun-earth L2 point, effective approaches were developed for designing preliminary fuel-optimal near-earth asteroid flyby trajectories. The approaches include the use of modified unstable manifolds, grid search of the manifolds＇ parameters, and a two-impulse maneuver for orbital phase matching and z-axis bias change, and are demonstrated to be effective in asteroid target screening and trajectory optimization. Asteroid flybys are expected to be within a distance of 2 × 10^7 km from the earth owing to the constrained earth-spacecraft communication range. In this case, the spacecraft＇s orbital motion is significantly affected by the gravities of both the Sun and the earth, and therefore, the concept of the ＂he- liocentric oscillating-Kepler orbit＂ is proposed, because the classical orbital elements of the flyby trajectories referenced in the heliocentric inertial frame oscillate significantly with respect to time. The analysis and results presented in this study show that, among the asteroids whose orbits are the most accurately predicted, ＂Toutatis＂, ＂2005 NZ6＂, or ＂2010 CL19＂ might be encountered by Chang＇e-2 in late 2012 or 2013 with total impulses less than 100 rn/s.

关键词： Chang'e-2 Asteroid flyby Sun-earth L2 Modified unstable manifolds Oscillating-Kepler orbit

Identification, characterization and evolution of non-local quasi-Lagrangian structures in turbulence

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Acta Mechanica Sinica 2016年第3期32卷 351-361页

作者： Yue yang State Key Laboratory for Turbulence and Complex Systems(LTCS) and Center for Applied Physics and Technology(CAPT) College of Engineering Peking University

The recent progress on non-local Lagrangian and quasi-Lagrangian structures in turbulence is *** quasi-Lagrangian structures, e.g., vortex surfaces in viscous flow, gas-liquid interfaces in multi-phase flow, and flame fronts in premixed combustion, can show essential Lagrangian following properties, but they are able to have topological changes in the temporal evolution. In addition,they can represent or influence the turbulent flow field. The challenges for the investigation of the non-local structures include their identification, characterization, and *** improving understanding of the quasi-Lagrangian structures is expected to be helpful to elucidate crucial dynamics and develop structure-based predictive models in turbulence.

关键词： Turbulence Lagrangian study Coherent structure Multi-scale analysis Vortex dynamics

Human ear Image Recognition Method Using PCA and Fisherface Complementary Double Feature extraction

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Journal of Artificial Intelligence and Technology 2023年第1期3卷 18-24页

作者： yang Wang Ke Cheng Shenghui Zhao Xu e School of Computer and Information engineering Chuzhou UniversityChuzhou 239000AnhuiChina School of Computer Jiangsu University of Science and TechnologyZhenjiang 212000JiangsuChina School of Information Science and Technology Bohai UniversityJinzhou 121013LiaoningChina

ear recognition is a new kind of biometric identification technology *** extraction is a key step in pattern recognition technology,which determines the accuracy of classification *** method of single feature extraction can achieve high recognition rate under certain conditions,but the use of double feature extraction can overcome the limitation of single feature *** order to improve the accuracy of classification results,this paper proposes a new method,that is,the method of complementary double feature extraction based on Principal Component Analysis(PCA)and Fisherface,and we apply it to human ear image *** experiment was carried out on the ear image library provided by the University of Science and Technology *** results show that the ear recognition rate of the proposed method is significantly higher than the single feature extraction using PCA,Fisherface,or Independent component analysis(ICA)alone.

关键词： PCA ICA single feature extraction double feature extraction ear recognition

Maximal function characterizations of Musielak-Orlicz-Hardy spaces associated with magnetic Schriidinger operators

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Frontiers of Mathematics in China 2015年第5期10卷 1203-1232页

作者： Dachun yang Dongyong yang School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China School of Mathematical Sciences Xiamen University Xiamen 361005 China

Let φ be a growth function, and let A ：= -（V- ia）. （V- ia）＋ V be a magnetic SchrSdinger operator on L2（Rn）, n≥ 2, where a ：= （a1, a2... an） ∈ r L1 loc（Rn） We establish the equivalent characteriza- L2 1oc（Rn, Rn） and 0 ≤ V ∈Lloc（Rn） tions of the Musielak-Orlicz-Hardy space HA,^（IRn）, defined by the Lusin area function associated with {e-t2A}t〉0, in terms of the Lusin area function associated with {e-t√A}t〉0, the radial maximal functions and the non- tangential maximal functions associated with {e-t2A}t〉o and {e-t√A}t〉0, respectively. The boundedness of the Riesz transforms LkA-U1/2, k ∈ {1, 2... n}, from HA,φ（Rn） to Lφ（Rn） is also presented, where Lk is the closure of δ/δxk iak in L2（Rn）. These results are new even when φ（x,t）：= w（x）tp for all x ∈Rn and t∈ （0, ＋∞） with p ∈ （0, 1] and ω∈ A∞（Rn）（the class of Muckenhoupt weights on Rn）.

关键词： Magnetic SchrSdinger operator Musielak-Orlicz-Hardy space Lusinarea function growth function maximal function Riesz transform