oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 14 )

2018 ( 110 )

2017 ( 106 )

2016 ( 109 )

Custom range...

Search Results: 1 - 10 of 7873 matches for " ChuanYun Dai "
All listed articles are free for downloading (OA Articles)
Page 1 /7873
Display every page Item
Linkage with cathepsin B-sensitive dipeptide promotes the in vitro and in vivo anticancer activity of PEGylated tumor necrosis factor-alpha (TNF-α) against murine fibrosarcoma
ChuanYun Dai,Ya Fu,Biao Li,YiGuang Wang,Xuan Zhang,JianCheng Wang,Qiang Zhang
Science China Life Sciences , 2011, DOI: 10.1007/s11427-010-4124-z
Abstract: To improve the pharmacological profile of tumor necrosis factor alpha (TNF-α), we have synthesized a new PEGylated prodrug, PEG-vcTNF-α, using a cathepsin B-sensitive dipeptide (valine-citrulline, vc) to link branched PEG and TNF-α. PEG-modified TNF-α without the dipeptide linker (PEG-TNF-α) and unconjugated TNF-α were also tested as controls. It was found for the first time that TNF-α released from PEG-vcTNF-α was specifically dependent on the presence of cathepsin B. PEG-vcTNF-α induced higher cytotoxicity and greater apoptosis against L929 murine fibrosarcoma cells than PEG-TNF-α. Reversal of these effects by a cathepsin-B inhibitor confirmed that these effects were mediated by cathepsin B-specific release of TNF-α. In vivo pharmacokinetics studies demonstrated that the plasma stability of PEG-vcTNF-α was significantly increased compared to TNF-α. Finally, the improved anticancer efficacy of PEG-vcTNF-α and the distinct activities among the three formulations confirmed the positive contribution of both PEGylation and the dipeptide linkage to the improved drug-like properties of PEG-vcTNF-α. The results here indicate that linking proteins and PEG via the cathepsin B-sensitive dipeptide may be a promising strategy for developing protein therapeutics.
The Strong Chromatic Index of graphs with maximum degree $Δ$
Chuanyun Zang
Mathematics , 2015,
Abstract: A strong edge-coloring of a graph $G$ is an edge-coloring such that no two edges of distance at most two receive the same color. The strong chromatic index $\chi'_s(G)$ is the minimum number of colors in a strong edge-coloring of $G$. P. Erd\H{o}s and J. Ne\v{s}et\v{r}il conjectured in 1985 that $\chi'_s(G)$ is bounded above by $\frac54\Delta^2$ when $\Delta$ is even and $\frac14(5\Delta^2-2\Delta+1)$ when $\Delta$ is odd, where $\Delta$ is the maximum degree of $G$. In this paper, we give an algorithm that uses at most $2\Delta^2-3\Delta+2$ colors for graphs with girth at least $5$. And in particular, we prove that any graph with maximum degree $\Delta=5$ has a strong edge-coloring with $37$ colors.
Preparation and evaluation of a new releasable PEGylated tumor necrosis factor-α (TNF-α) conjugate for therapeutic application
ChuanYun Dai,Ya Fu,ShaoCheng Chen,Biao Li,Bo Yao,WanHong Liu,LiQing Zhu,Nan Chen,Ji Chen,Qiang Zhang
Science China Life Sciences , 2013, DOI: 10.1007/s11427-012-4431-7
Abstract: To design a releasable PEGylated TNF-α (rPEG-TNF-α), a cathepsin B-sensitive dipeptide (Val-Cit moiety) was inserted into conventional PEG-modified TNF-α (PEG-TNF-α), facilitating its clinical use for anti-tumor therapy. Comparative pharmacokinetic and pharmacodynamic studies showed that the half-lives of both PEGylated forms of TNF-α were ~60-fold greater than that of unmodified TNF-α. In addition, the in vitro bioactivity of rPEG-TNF-α was greater than that of PEG-TNF-α with the same degree of PEG modification. Release of TNF-α from rPEG-TNF-α in vitro was dependent on the presence of cathepsin B and was inhibited by a cathepsin B inhibitor. Despite the potent cytotoxicity of unmodified TNF-α against normal cells, its PEGylated forms at higher TNF-α concentrations showed low cytotoxic activity against these cells. In contrast, both forms of PEGylated TNF-α showed potent cytotoxic activity against the B16 and L929 cell lines, with rPEG-TNF-α being 5- and 9-fold more potent, respectively, than PEG-TNF-α. Moreover, rPEG-TNF-α was a more potent in vivo antitumor agent than PEG-TNF-α.
Minimum vertex degree thresholds for tiling complete 3-partite 3-graphs
Jie Han,Chuanyun Zang,Yi Zhao
Mathematics , 2015,
Abstract: Given positive integers $a\leq b \leq c$, let $K_{a,b,c}$ be the complete 3-partite 3-uniform hypergraph with three parts of sizes $a,b,c$. Let $H$ be a 3-uniform hypergraph on $n$ vertices where $n$ is divisible by $a+b+c$. We asymptotically determine the minimum vertex degree of $H$ that guarantees a perfect $K_{a, b, c}$-tiling, that is, a spanning subgraph of $H$ consisting of vertex-disjoint copies of $K_{a, b, c}$. This partially answers a question of Mycroft, who proved an analogous result with respect to codegree for $r$-uniform hypergraphs for all $r\ge 3$. Our proof uses a lattice-based absorbing method, the concept of fractional tiling, and a recent result on shadows for 3-graphs.
Design and Implementation of Flight Visual Simulation System
Feng Tian,Wenjian Chai,Chuanyun Wang,Xiaoping Sun
International Journal of Computer Science Issues , 2012,
Abstract: The design requirement for flight visual simulation system is studied and the overall structure and development process are proposed in this paper. Through the construction of 3D scene model library and aircraft model, the rendering and interaction of visual scene are implemented. The changes of aircraft flight attitude in visual system are controlled by real-time calculation of aircraft aerodynamic and dynamic equations and flight simulation effect is enhanced by this kind of control. Several key techniques for optimizing 3D model and relative methods for large terrain modeling are explored for improving loading ability and rendering speed of the system. Experiment shows that, with specific function and performance guaranteed as a premise, the system achieves expected results, that is, precise real-time calculation of flight attitude and smooth realistic screen effect.
The Influence of Contributory Factors on Driving Violations at Intersections: An Exploratory Analysis
Chuanyun Fu,Yulong Pei,Yuqing Wu,Weiwei Qi
Advances in Mechanical Engineering , 2013, DOI: 10.1155/2013/905075
Abstract: Driving violation has been identified as one of the prominent contributing factors involved in crashes occurring at intersections. However, very little literature has studied the influence of contributory factors on driving violation. The goal of the present study was to analyze the effect of contributory factors on traffic sign and signals (TSS) violation, turning-yielding-signaling (TYS) violation, and speeding related (SR) violation at intersections, and the likelihood of each type of driving violation was predicted by using a multinomial logistic model. The findings of this study indicated that younger drivers (ages 15–24) had a propensity to commit SR violations, but older drivers (ages 65+) had the adverse situations. The likelihood of SR violations for males was higher than TYS violations, while contrary outcome was obtained during daylight. At traffic sign or signals controlled intersections, the odds of TSS violations and TYS violations were greater than SR violations, and similar outcomes were gained in four-way intersections or T-intersections. Drivers distracted cognitively were more likely to be in commission of TYS violations than SR violations, whereas it is opposite to passenger or in-vehicle related distractions. Inattention/distraction significantly affected the likelihood of each type of driving violation. Implications of the findings from current study are discussed. 1. Introduction Intersection is the conjunction node of the whole road network, and traffic flows from different directions converge there. Drivers have to spare their attention from the main driving tasks to other relevant things (e.g., traffic sign or signals, crossing vehicles and pedestrians, etc.) due to the dynamic and complex situation at intersections [1]. Potential conflicts and crashes between road users are more likely to occur [2]. In the United States, there were 6,898 fatalities resulting from motor vehicle crashes at intersections in 2011 [3], and 1,126 estimated fatalities happened at the signalized intersections and 1,492 estimated fatalities at the stop/yield controlled intersections [4]. Driving violation, as one type of driving errors [5], has been identified as a prominent factor involved in the crashes occurring at intersections [2]. The three most common types of violation that impair the driving performance for drivers are turning-yielding-signaling (TYS) violation, traffic sign and signals (TSS) violation, and speed related (SR) violation [4]. TYS violations usually occur when drivers fail to properly turn, or fail to signal for turn or stop, and
Coverage dependence of the 1-propanol adsorption on the Si(001) surface and fragmentation dynamics
Jian-Ge Zhou,Frank Hagelberg,Chuanyun Xiao
Physics , 2006, DOI: 10.1103/PhysRevB.73.155307
Abstract: The geometric, electronic, energetic, and dynamic properties of 1-propanol adsorbed on the Si(001)-2x1 surface are studied from first principles by use of a slab approach. The 1-propanol molecule initially interacts with the Si surface through formation of a dative bond, subsequently the physisorbed 1-propanol molecule reacts with the surface by cleavage of the O-H bond, and the Si(001)-2x1 surface undergoes further reconstruction as a result of the adsorption of the organic species. The band structure and density of states (DOS) are first analyzed for this system. The band gap of the Si/1-propanol film increases as the coverage level is enhanced. Good agreement is found with available experimental data.
Design and Implementation of Flight Visual Simulation System
Feng Tian,Wenjian Chai,Chuanyun Wang,Xiaoping Sun
Computer Science , 2012,
Abstract: The design requirement for flight visual simulation system is studied and the overall structure and development process are proposed in this paper. Through the construction of 3D scene model library and aircraft model, the rendering and interaction of visual scene are implemented. The changes of aircraft flight attitude in visual system are controlled by real-time calculation of aircraft aerodynamic and dynamic equations and flight simulation effect is enhanced by this kind of control. Several key techniques for optimizing 3D model and relative methods for large terrain modeling are explored for improving loading ability and rendering speed of the system. Experiment shows that, with specific function and performance guaranteed as a premise, the system achieves expected results, that is, precise real-time calculation of flight attitude and smooth realistic screen effect.
"universe collapse model" and its roles in the unification of four fundamental forces and the origin and the evolution of the universe  [PDF]
Jiapei Dai
Natural Science (NS) , 2012, DOI: 10.4236/ns.2012.44030
Abstract: To unify the four known fundamental forces and provide an explanation for the origin and the evolution of the universe are two long-term goals of theoretical physics. Here a “universe collapse model” has been proposed. The universe consists of Matter and No-matter. No-matter is the universal energy that constructs a consistent universe field, presenting a spiral wave motion at the speed of light at the small scale. The partial collapse of the universal energy forms the particles of the universal energy in a variety of sizes, which are called as the elementary particles. These elementary particles form atom and matter, which construct the galaxies. The collapse of the universe field induces the formation of the universe collapse potential (UCP) and universe collapse force (UCF), and the later is represented by four different aspects of the fundamental forces at the large or small scales. The mathematical equation and the derivation of UCP and UCF are described, and possible experimental tests are also suggested. Therefore, this new model may give a novel explanation for the unification of four fundamental forces and the origin and the evolution of the universe.
Research on Influencing Factors of Executive Compensation in China’s Monopoly Industries  [PDF]
Yun Dai
Open Journal of Business and Management (OJBM) , 2014, DOI: 10.4236/ojbm.2014.23026
Abstract: The annual salary income of the executives in the state-owned monopoly industry has become the focus of the society recently. With the improvement of enterprise efficiency, executives deserve to get high pay. However, it’s should be noted that because of the state-owned monopolies’ special status, business performance relies heavily on administrative monopoly power, but not actually the efforts of leaders. In this case, the income distribution mechanism is distortion, which has caused great dissatisfaction. This paper aims to study the main affecting factors of the executive compensation of state monopolies, with 1280 firm-year observations of 183 monopoly companies. We find that 1) Executive compensation is positively correlated to firm performance, firm size, CEO duality; 2) Executive compensation is negatively correlated to state share proportion and independent director proportion; 3) Company location, industry both have significant influence on executive compensation.
Page 1 /7873
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.