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Human prostate cancer stem cells： new features unveiled

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Asian Journal of Andrology 2011年第3期13卷 355-356页

作者： Yuting Sun wei-qiang Gao Department of Discovery Oncology Genentech Inc. South San Francisco CA 94080 USA Renji-MedX Clinical Stern Cell Research Center Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200127 China Med-X Research Institute Shanghai Jiao Tong University Shanghai 200030. China

Cancer stem cells （CSCs） are a rare subpopulation of phenotypically distinct cancer cells exhibiting stem cell characteristics. They are tumourigenic, meanwhile capable of self-renewal and forming differentiated progenies. CSCs are believed to be resistant to the standard therapeutics, and provide the cell reservoir for tumour initiation.1 Understanding CSCs or in another word, tumour-initiating cells, is of critical therapeutic importance.

关键词： Cells Lymphocytes Cancer (genus) Neoplasms Stems

Study of the expressions of p53 and bcl-2 genes, the telomerase activity and apoptosis in GIST patients

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World Journal of Gastroenterology 2007年第18期13卷 2626-2628页

作者： qiang wang You-wei Kou Department of Gastrointestinal Surgery Shenjing Hospital of China Medical University Shenyang110004 Liaoning Province China

AIM： To explore the relationship between clinicobiological behavior and the expression levels of telomerase activity, apoptosis, p53 gene and bcl-2 gene in gastrointestinal stromal tumors （GISTs）. METHODS： The intensity of telomerase activity, apoptosis, p53 and bcl-2 expression in GISTs were detected by telomeric repeat amplification protocol, in situ end-labeling technique, and immunohistochemistry, respectively. RESULTS： The positive rates of telomerase activity of malignant GIST, potential malignant GIST and benign GIST were 85% （17/20）, 22.8% （2/9） and 0 （0/9）, respectively. The apoptosis indices of malignant GIST, potential malignant GIST, and benign GIST were 11.7±5.4, 30.2±5.6 and 45.2 ±7.2, respectively. The intensity of telomerase activity and apoptosis were related to the biological characteristics of GISTs （85% vs 22.8%, 0, 0; P 〈 0.01 or 11.7±5.4 vs 30.2±5.6, 45.2±7.2, 72.1±9.3; P 〈 0.05）. The intensity of telomerase activity was negatively correlated with cellular apoptosis （22.9±8.4 vs 9.5±5.7, P 〈 0.01）. The intensity of telomerase activity was positively correlated with/753, bcl-2 expression （40.0% vs 78.9%, 40.0% vs 84.2%; P 〈 0.05）. CONCLUSION： The detection of telomerase activity, apoptosis and its control genes in GIST will be helpful for the discrimination of the malignant and benign GIST and evaluation of the prognosis.

关键词： Gastrointestinal stmmal tumors Telomerase p53 bcl-2 Apoptosis

A novel gain design method to improve the consensus performance of output-feedback multi-agent systems

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Control Theory and Technology 2016年第4期14卷 335-346页

作者： wei ZHENG qiang LING Hai LIN Department of Automation University of Science and Technology of China Hefei Anhui 230027 China Department of Electrical Engineering University of Notre Dame Notre Dame IN 46556 U.S.A.

This paper considers the consensus problem of a group of homogeneous agents. These agents are governed by a general linear system and can only directly measure the output, instead of the state. In order to achieve the consensus goal, each agent estimates its state through a Luenberger observer, exchanges its estimated state with neighbors, and constructs the control input with the estimated states of its own and neighbors. Due to the existence of observation and process noises, only practical consensus, instead of asymptotical consensus, can be achieved in such multi-agent systems. The performance of the achieved practical consensus can be measured by the ultimate mean square deviation of the states of agents. That performance is closely related to the observation gains of the state observers and the control gains of agents. This paper proposes a method to optimize such performance with respect to the concerned observation and control gains. That method starts with a set of feasible observation and control gains and formulates a group of linear matrix inequalities （LMIs）. Solving these LMIs gives some intermediate matrix variables. By perturbing observation and control gains, and the intermediate matrix variables, the original LMIs yield another group of LMIs, which can be solved to provide a descent direction of observation and control gains. Moving along that descent direction, observation and control gains can be improved to yield better performance and work as the starting point of the next iteration. By iteratively repeating this procedure, we can hopefully improve the consensus performance of the concerned multi-agent system. Simulations are done to demonstrate the effectiveness of the proposed method.

关键词： Consensus output-feedback multi-agent systems least mean square deviation perturbation method

Factors to consider in developing individual pharmaceutical product quality risk profiles useful to government procurement agencies

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Acta Pharmaceutica Sinica B 2016年第1期6卷 79-92页

作者： wei Xu Garth Boehm qiang Zheng School of Pharmaceutical Sciences Peking University Center for Pharmaceutical Information and Engineering Research Peking University Department of Industrial Engineering and Management College of EngineeringPeking University

Governments that procure pharmaceutical products from an Essential Medicine List(EML)bear special responsibility for the quality of these *** this article we examine the possibility of developing a pharmaceutical product quality risk assessment scheme for use by government procurement *** use the Chinese EML as a basis,and US recall data is examined as it is publically *** is justified as the article is only concerned with inherent product quality *** establishing a link between Chinese essential medicines and those available in the US,we examine US recall data to separate product specific *** conclude that,in addition to existing manufacturing based risks,there are two other product specific risks that stand out from all others,degradation and dissolution *** for relative product risk for degradation is needed to be developed and further work is required to better understand dissolution failures which largely occur with modified-release solid oral *** conclude that a product specific quality risk profile would be enhanced by including a risk assessment for degradation for all products,and in the case of solid oral products,dissolution.

关键词： Chinese essential medicine Product-specific quality risk Chemical stability Dissolution Risk assessment US recall data

Optimal congestion control algorithm for ad hoc networks: Penalty function-based approach

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 2110-2117页

作者： XU wei-qiang WU Tie-jun School of Information Science and Engineering Zhejiang University Hangzhou 310027 China College of Informatics and Electronics Zhejiang Sci-Tech University Hangzhou 310018 China

In this paper, based on the inherent characteristic of the contention relation between flows in ad hoc networks, we introduce the notion of the link＇s interference set, extend the utility maximization problem representing congestion control in wireline networks to ad hoc networks, apply the penalty function approach and the subgradient method to solve this problem, and propose the congestion control algorithm Penalty function-based Optical Congestion Control （POCC） which is implemented in NS2- simulator. Specifically, each link transmits periodically the information on its congestion state to its interference set; the set ; the sermon at each source adjusts the transmission rate based on the optimal tradeoffbetween the utility value and the congestion level which the interference set of the links that this session goes though suffers from. MATLAB-based simulation results showed that POCC can approach the globally optimal solution. The NS2-based simulation results showed that POCC outperforms default TCP and ATCP to achieve efficient and fair resource allocation in ad hoc networks.

关键词： Ad hoc networks Congestion control Subgradient Penalty function

Orbifold Gromov–Witten Invariants of weighted Blow-up at Smooth Points

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Acta Mathematica Sinica,English Series 2015年第5期31卷 825-846页

作者： wei qiang HE Jian Xun HU Department of Mathematics Sun Yat-Sen University

In this paper, one considers the change of orbifold Gromov Witten invariants under weighted blow-up at smooth points. Some blow-up formula for Gromov-Witten invariants of sym- pleetic orbifolds is proved. These result... 详细信息

关键词： Gromov-Witten invariant orbifold weighted blow-up

Soil Aggregates and Fractal Features under Different Land Use Types in a Frequent Debris Flow Area

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Journal of Mountain Science 2013年第3期10卷 437-444页

作者： XIE Xian-jian wei Fang-qiang School of Geography and Resources Science Neijiang Normal University Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The stability of soil aggregates and the fractal characteristics of four typical land use types(farmland,grassland,woodland,and bare land) in the Jiangjiagou Ravine(Yunnan,China),a frequent debris flow occurring area,were studied according to the normal mean mass diameter and fractal *** present research showed that the stability of the soil aggregates was different for the different land use *** the soil depth was 0-30 cm,farmland soil formed more aggregates with diameters greater than 0.25 mm,i.e.,the farmland soil was more stable than that of the other three land *** the soil depth was 30-45 cm,the order of stability of the soil aggregates was woodland > grassland > farmland > bare *** fractal dimensions had a significant linear positive correlation with the amount of soil particles with diameters of <0.25 mm,and a significant negative linear correlation with the amount of soil particles with diameters of 0.25-0.5 mm,0.5-1 mm and 1-2 *** fractal dimensions of the soil particles correlated with more stable soil *** fractal dimensions had a positive linear correlation with the soil bulk density and a negative correlation with the concentration of organic *** results showed that soil aggregates can be used as a parameter for characterizing the soil structures and *** to these results,the soil particle fractal dimensions could not only objectively characterize the stability of the soil structure but also could be used to indicate soil structure and *** addition,these results have great significance for the discussion of the comprehensive evaluation of soil.

关键词： Debris flow Land use pattern Aggregates Fractal dimension

Propagation of elastic wave in nanoporous material with distributed cylindrical nanoholes

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1542-1550页

作者： qiang Fangwei wei PeiJun LIU Xiqiang Department of Applied Mechanics University of Science and Technology Beijin Department of Mathematics & Physics PLA University of Science and Technology

The effective propagation constants of plane longitudinal and shear waves in nanoporous material with random distributed parallel cylindrical nanoholes are studied. The surface elastic theory is used to consider the surface stress effects and to derive the nontraditional boundary condition on the surface of nanoholes. The plane wave expansion method is used to obtain the scattering waves from the single nanohole. The multiple scattering effects are taken into consideration by summing the scat- tered waves from all scatterers and performing the configuration averaging of random distributed scatterers. The effective propagation constants of coherent waves along with the associated dynamic effective elastic modulus are numerically evaluat- ed. The influences of surface stress are discussed based on the numerical results.

关键词： multiple scattering nanohole coherent wave effective velocity effective modulus

Information Flow Scheduling in Concurrent Multi-Product Development Based on DSM

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1101-1111页

作者： Qing-Chao Sun wei-qiang Huang Ying-Jie Jiang wei Sun School of Mechanical Engineering Dalian University of Technology

Multi-product collaborative development is adopted widely in manufacturing enterprise, while the present multi-project planning models don＇t take techni- cal/data interactions of multiple products into account. To decrease the influence of technical/data interactions on project progresses, the information flow scheduling models based on the extended DSM is presented. Firstly, infor- mation dependencies are divided into four types： series, parallel, coupling and similar. Secondly, different types of dependencies are expressed as DSM units, and the exten- ded DSM model is brought forward, described as a block matrix. Furthermore, the information flow scheduling methods is proposed, which involves four types of opera- tions, where partitioning and clustering algorithm are modified from DSM for ensuring progress of high-priority project, merging and converting is the specific computation of the extended DSM. Finally, the information flow scheduling of two machine tools development is analyzed with example, and different project priorities correspond to different task sequences and total coordination cost. The proposed methodology provides a detailed instruction for information flow scheduling in multi-product development, with specially concerning technical/data interactions.

关键词： Concurrent multi-product development Information flow planning Extended DSM Projectpriority