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An efficient approach for continuous density queries

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Frontiers of Computer Science 2012年第5期6卷 581-595页

作者： jie wen Xiaofeng MENG Xing HAO Jianliang XU School of Information Renmin University of ChinaBeijing 100872China Department of Computer Science Hong Kong Baptist UniversityHong KongChina

In location-based services, a density query re- turns the regions with high concentrations of moving objects （MOs）. The use of density queries can help users identify crowded regions so as to avoid congestion. Most of the exist- ing methods try very hard to improve the accuracy of query results, but ignore query efficiency. However, response time is also an important concern in query processing and may have an impact on user experience. In order to address this issue, we present a new definition of continuous density queries. Our approach for processing continuous density queries is based on the new notion of a safe interval, using which the states of both dense and sparse regions are dynamically main- tained. Two indexing structures are also used to index candi- date regions for accelerating query processing and improving the quality of results. The efficiency and accuracy of our approach are shown through an experimental comparison with snapshot density queries.

关键词： continuous density queries safe interval query efficiency

Interaction of Mixed Porphyrin-polypyridyl Ru(II) Complex with Bovine Serum Albumin

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Chemical Research in Chinese Universities 2010年第5期26卷 693-698页

作者： XU Lei LIU Ya-nan MEI wen-jie HUANG Xiao-mei CHEN Tian-feng LIU jie ZHENG wen-jie Department of Chemistry Jinan University Guangzhou 510632 P. R. China School of Pharmacy Guangdong Pharmaceutical University Guangzhou 510006 P. R. China

The interactions of mixed porphyrin-polypyridyl Ru（Ⅱ） complexes [m（Py-3＇）TPP-Ru（phen）2Cl]^＋（1） and its derivatives [Nim（Py-3＇）TPP-Ru（phen）2Cl]＋（2） and [Cum（Py-3＇）TPP-Ru（phen）2Cl]^＋（3）（phen=1,10-phenanthroline; m（Py-3＇）TPP=5-（3＇-pyridyl）-10,15,20-triphenylporphyrin） with bovine serum albumin（BSA） were investigated by fluorescence, UV-Vis and circular dichroism（CD） spectroscopies. The UV-Vis and CD spectral experiments indicated that the secondary structures of the protein were perturbed in the presence of the porphyrin Ru（Ⅱ） complex and the perturbation was enhanced under the irradiation with ultra-violet light. The fluorescence quenching mechanism of BSA by the three complexes was determined to be a static process, and the apparent binding constant K values for complexes 1, 2 and 3 measured by fluorescence quenching method were （3.86±0.03）×10^3 L/mol（n=0.94±0.04）, （5.69±0.04）× 103 L/mol（n=1.03±0.06）, and （6.54±0.02）× 10^3 L/mol（n=1.03±0.05）, respectively.

关键词： Porphyrin Bovine serum albumin(BSA) Ru(Ⅱ) complex Binding

Formation Sites and Microscopic Conformation Study on the Konjac Glucomannan Molecular Helices

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1084-1090页

作者： JIAN wen-jie WANG Meng YAO Min-Na PANG jie Department of Biological Technology Xiamen Ocean Vocational College Xiamen 361012 China College of Food Science Fujian Agriculture and Forestry University Fuzhou 350002 China

In this work, the formation sites, helical parameters and hydrogen bond positions of Konjac glucomannan molecular helices were investigated using molecular dynamic simulation method. To our interest, the KGM chain is mainly composed by local left and right helix struetttres. The formation sites of KGM chain might locate at the chain-segments containing acetyl groups, and the left helix is the favorable conformation of KGM. Temperature-dependent molecule conformation study indicates that the right helix is dominant when the temperature is lower than 343 K, above which, however, the left helix is dominating （right helix disappears）. In addition, intramolecular hydrogen bonds in the left helix can be found at the -OH groups on C（2）, C（4） and C（6） of mannose residues; comparably, the intramolecular hydrogen bonds in the right helix can be mainly observed at the -OH groups on C（4） and C（6） of the mannose residues and C（3） of the glucose residues. In conclusion, molecular dynamic simulation is an efficient method for the microscopic conformation study of glucomannan molecular helices.

关键词： Konjac glucomannan helical structure formation sites helical parameters,hydrogen bond sites

Bayesian inference of the crust–core transition density via the neutron-star radius and neutron-skin thickness data

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Nuclear Science and Techniques 2023年第6期34卷 125-133页

作者： wen-jie Xie Zi-Wei Ma Jun-Hua Guo Department of Physics Yuncheng UniversityYuncheng044000China

In this work,we perform a Bayesian inference of the crust-core transition density ρ_(t) of neutron stars based on the neutron-star radius and neutron-skin thickness data using a thermodynamical *** and Gaussian distributions for the ρ_(t) prior were adopted in the Bayesian *** has a larger probability of having values higher than 0.1 fm^(−3) for ρ_(t) as the uniform prior and neutron-star radius data were *** was found to be controlled by the curvature K_(sym) of the nuclear symmetry *** phenomenon did not occur if K_(sym) was not extremely negative,namely,K_(sym)>−200 *** value ofρ_(t) obtained was 0.075_(−0.01)^(+0.005) fm^(−3) at a confidence level of 68%when both the neutron-star radius and neutron-skin thickness data were *** anti-correlations were observed between ρ_(t),slope L,and curvature of the nuclear symmetry *** dependence of the three L-K_(sym) correlations predicted in the literature on crust-core density and pressure was quantitatively *** most probable value of 0.08 fm^(−3) for ρ_(t) was obtained from the L-K_(sym) relationship proposed by Holt et *** larger values were preferred for the other two relationships.

关键词： Crust–core transition density of neutron stars Neutron-star radius Neutron-skin thickness Bayesian inference approach L–K_(sym)

Flux-pinning-induced stress behaviors in a long superconducting slab with central cuboid hole

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Acta Mechanica Sinica 2021年第8期37卷 1255-1263,I0001页

作者： Qi-Fang Liu wen-jie Feng Jia-Yu Liu School of Civil Engineering Shandong UniversityJinan 250061China State Key Lab Mech Behav&Syst Safety Traff Engn Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Key Lab Smart Mat&Struct Mech Shijiazhuang Tiedao UniversityShijiazhuang 050043China

This paper investigates the flux-pinning-induced stress behaviors in a long superconducting slab with a central cuboid *** distribution of flux density is analytically derived for the critical current density of Kim model by considering the effects of the *** concentration of stress for both of the zero-field cooling(ZFC)and the field cooling(FC)magnetization processes are investigated through numerical simulation by using finite element *** results indicate the potential failure mode varies with the height-width ratio and the dimensions of the *** to the case of infinite hole height,the stress concentration behavior for the FC process is more critical when the dimensions of the hole are *** findings in this paper are useful for understanding of the degrade mechanism of superconductor in service and the design of new system.

关键词： Electromagnetic force Cuboid hole Stress concentration factor Superconducting slab

Obesity and cancer stem cells:Roles in cancer initiation,progression and therapy resistance

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World Journal of Stem Cells 2023年第4期15卷 120-135页

作者： wen-jie Xie Jian Li Department of General Surgery The Third Hospital of MianyangSichuan Mental Health CenterMianyang 621000Sichuan ProvinceChina

Obesity,the global pandemic since industrialization,is the number one lifestylerelated risk factor for premature death,which increases the incidence and mortality of various diseases and conditions,including *** recent years,the theory of cancer stem cells(CSCs),which have the capacity for self-renewal,metastasis and treatment resistance,has been bolstered by increasing ***,research on how obesity affects CSCs to facilitate cancer initiation,progression and therapy resistance is still in its infancy,although evidence has already begun to *** the ever-increasing burden of obesity and obesity-related cancer,it is pertinent to summarize evidence about the effects of obesity on CSCs,as elucidating these effects will contribute to the improvement in the management of obesity-related *** this review,we discuss the association between obesity and CSCs,with a particular focus on how obesity promotes cancer initiation,progression and therapy resistance through CSCs and the mechanisms underlying these *** addition,the prospect of preventing cancer and targeting the mechanisms linking obesity and CSCs to reduce cancer risk or to improve the survival of patients with cancer is considered.

关键词： Obesity High-fat diet Cancer stem cells Carcinogenesis Metastasis

Quantum to Classical Transition in a System of Two Coupled Kicked Rotors

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Communications in Theoretical Physics 2009年第3期51卷 465-469页

作者： ZHAO wen-Lei jie Quan-Lin Department of Physics Wuhan University Wuhan 430072 China

We investigate the quantum-classical transition in a system of two coupled kicked rotors. We lind that when the mass of one kicked rotor is much smaller than the other＇s, the influence of the light kicked rotor is still able to make decoherence of the heavy one. This leads to the quantum-classical transition of the heavy kicked rotor. We demonstrate this by two different coupling potentials.

关键词： quantum chaos quantum-classical transition entanglement kicked rotor

Structural evolution of mesoporous graphene/LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2) composite cathode for Li-ion battery

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Rare Metals 2021年第3期40卷 521-528页

作者： wen-jie Liu Xian-Zhong Sun Xiong Zhang Chen Li Kai Wang wen wen Yan-Wei Ma Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China

Layered LiMO_(2)(M=Ni,Co,and Mn) is a type of promising cathode materials for high energy density and high work voltage lithium-ion ***,the poor rate performance and low power density hinder its further *** capacity fade is related to the structural transformation in the layered LiMO_(2).In this work,the structural changes of bi-material cathode composed of mesoporous graphene and layered LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2)(NCM) were studied via in situ X-ray diffraction(XRD).During different C-rate charge-discharge test at the voltage range of 2.5-4.1 V,the composite cathode of NCM-graphene(NCM-G) reveals better rate performances than pure NCM *** NCM-G composite electrode displays a higher rate capability of 76.7 mAh·g^(-1) at 5 C rate,compared to the pure NCM cathode of 69.8 mAh·g^(-1)discharge *** in situ XRD results indicate that a reversible phase transition from hexagonal H1 to hexagonal H2 occurs in layered NCM material during 1 C chargedischarge *** the current increasing to 2 C/5 C,the structure of layered NCM material for both electrodes reveals few changes during charge and discharge processes,which indicates the less utilization of NCM component at high ***,the improved rate performance for bi-material electrode is attributed to the highly conductive mesoporous graphene and the synergistic effect of mesoporous graphene and NCM material.

关键词： LiNi_(1/3)Co_(1/3)Mn_(1/3)O_(2)(NCM) Mesoporous graphene Bi-material In situ X-ray diffraction(XRD) Structural evolution

Online scheduling of jobs with kind release times and deadlines on a single machine

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 113-126页

作者： LI wen-jie MA Ran FENG Qi School of Mathematical Sciences Luoyang Normal University School of Mathematics and Statistics Qingdao University Department of Information and Computation Science Zhongyuan University of Technology

This paper studies online scheduling of jobs with kind release times on a single machine. Here "kind release time" means that in online setting, no jobs can be released when the machine is busy. Each job J has a kind release time r(J) ≥ 0, a processing time p(J) > 0 and a deadline d(J) > 0. The goal is to determine a schedule which maximizes total processing time( p(J)E(J)) or total number( E(J)) of the accepted jobs. For the first objective function p(J)E(J), we first present a lower bound 2(1/2), and then provide an online algorithm LEJ with a competitive ratio of 3. This is the first deterministic algorithm for the problem with a constant competitive ratio. When p(J) ∈ {1, k}, k > 1 is a real number, we first present a lower bound min{(1 + k)/k, 2 k/(1 + k)}, and then we show that LEJ has a competitive ratio of1 + k/k. In particular, when all the k length jobs have tight deadlines, we first present a lower bound max{4/(2 + k), 1}(for p(J)E(J)) and 4/3(for E(J)). Then we prove that LEJ is k/k-competitive for p(J)E(J) and we provide an online algorithm H with a competitive ratio of 2 k/( k + 1) for the second objective function E(J).

关键词： scheduling online algorithm kind release time deadline