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First record of Bursaphelenchus rainulfi on pine trees from eastern China and its phylogenetic relationship with intro-genus species

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第5期8卷 345-351页

作者： JIANG li-qin li xu-qing zheng Jing-wu Institute of Biotechnology School of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China

Bursaphelenchus rainulfi isolated from dead pine trees in Zbejiang, China, is described and illustrated. It also provided some molecular characters of the Chinese population, including the PCR-RFLP and sequences of ITS region and D2-D3 expansion region of the large subunit （LSU） rRNA gene. Both the morphological characters and ITS-RFLP patterns match with the original description. The phylogenetic trees based on the 13 sequences of D2-D3 expansion region of the LSU rRNA gene and ITS region of Bursaphelenchus species were constructed, respectively, with the results showing the similar clades. The phylogenetic relationship based on the molecular data is similar to that with morphological characters. This is the first report of the species on pine wood in eastern China.

关键词： Bursaphelenchus rainulfi Pine wood Morphology Morphometrics ITS-RFLP Phylogeny

Quantitative real-time RT-PCR detection for CEA, CK20 and CK19 mRNA in peripheral blood of colorectal cancer patients

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第6期7卷 445-451页

作者： xu Dong li xu-fen zheng Shu JIANG Wen-zhi Cancer Institute the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

This study is aimed at establishing a sensitive approach to detect disseminated tumor cells in peripheral blood and evaluate its clinical significance. A total of 198 blood samples including 168 from colorectal carcinoma (CRC) patients and 30 from healthy volunteers were examined by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) to evaluate the expression of carcinoembryonic antigen (CEA), cytokeratin 20 (CK20) and cytokeratin 19 (CK19) mRNA. CEA mRNA was detected in 35.8% of patients and 3.3% of controls, CK20 mRNA in 28.3% of patients and 6.7% of controls, and CK19 mRNA in 41.9% of patients and 3.3% of controls. CEA and CK20 mRNA positive ratio increased with the advancing Dukes stages, but there was no significant difference in positive ratio between any two stages (P>0.05). Also, relatively high positive ratio of CEA, CK20 and CK19 mRNA expression was observed in some CRC patients with earlier Dukes stages. A higher positive ratio was obtained when two or three detection markers were combined compared to a single marker. Our study indicates that quanti-tative real-time RT-PCR detection for CEA, CK20 and CK19 mRNA in peripheral blood is a valuable tool for monitoring early stage dissemination of CRC cells in blood circulation.

关键词： Colorectal carcinoma Real-time RT-PCR CEA mRNA CK20 mRNA CK19 mRNA

A new data structure for accelerating kinetic Monte Carlo method

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Research in Astronomy and Astrophysics 2019年第12期19卷 235-244页

作者： xu-li zheng Dong-Hui Quan Hai-Long Zhang Xiao-Hu li Qiang Chang Olli Sipila Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Department of Chemistry Eastern Kentucky UniversityRichmondKYUSA Max-Planck-Institute for Extraterrestrial Physics(MPE) Giessenbachstr.185748 GarchingGermany School of Astronomy and Space Science University of Chinese Academy of SciancesBeijing 100049China

The kinetic Monte Carlo simulation is a rigorous numerical approach to study the chemistry on dust grains in cold dense interstellar clouds. By tracking every single reaction in chemical networks step by step, this approach produces more precise results than other approaches but takes too much computing time. Here we present a method of a new data structure, which is applicable to any physical conditions and chemical networks, to save computing time for the Monte Carlo algorithm. Using the improved structure,the calculating time is reduced by 80 percent compared with the linear structure when applied to the osu-2008 chemical network at 10K. We investigate the effect of the encounter desorption in cold cores using the kinetic Monte Carlo model with an accelerating data structure. We found that the encounter desorption remarkably decreases the abundance of grain-surface H2 but slightly influences the abundances of other species on the grain.

关键词： astrochemistry molecular processes methods:numerical ISM:molecules ISM:abundances

Using Improved Particle Swarm Optimization Algorithm for Location Problem of Drone Logistics Hub

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Computers, Materials & Continua 2024年第1期78卷 935-957页

作者： li zheng Gang xu Wenbin Chen School of Mathematics and Computer Sciences Nanchang UniversityNanchang330031China

Drone logistics is a novel method of distribution that will become *** advantageous location of the logistics hub enables quicker customer deliveries and lower fuel consumption,resulting in cost savings for the company’s transportation *** firms must discern the ideal location for establishing a logistics hub,which is challenging due to the simplicity of existing models and the intricate delivery *** simulate the drone logistics environment,this study presents a new mathematical *** model not only retains the aspects of the current models,but also considers the degree of transportation difficulty from the logistics hub to the village,the capacity of drones for transportation,and the distribution of logistics hub ***,this paper proposes an improved particle swarm optimization(PSO)algorithm which is a diversity-based hybrid PSO(DHPSO)algorithm to solve this *** DHPSO,the Gaussian random walk can enhance global search in the model space,while the bubble-net attacking strategy can speed ***,Archimedes spiral strategy is employed to overcome the local optima trap in the model and improve the exploitation of the *** maintains a balance between exploration and exploitation while better defining the distribution of logistics hub locations Numerical experiments show that the newly proposed model always achieves better locations than the current *** DHPSO with other state-of-the-art intelligent algorithms,the efficiency of the scheme can be improved by 42.58%.This means that logistics companies can reduce distribution costs and consumers can enjoy a more enjoyable shopping experience by using DHPSO’s location *** the results show the location of the drone logistics hub is solved by DHPSO effectively.

关键词： Drone logistics location problem mathematical model diversity particle swarm optimization

Spherical Confinement Generates Entropic Force to Accelerate Polymer Chain Detachment

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Chinese Journal of Polymer Science 2024年第3期42卷 407-416,I0010页

作者： Yu-Shan zheng Jian-Ping Zhou Yan xu Kai li Mechanical Engineering Xinjiang UniversityUrumqi 830002China

To understand the dynamic process of polymer detachment, it is necessary to determine the mean detachment time of a single breakable link, which is modeled as a spring. Normally, this time can be viewed as the escape of a Brownian particle from the potential well of the spring. However, as the free dangling length of the polymer chain increases, the conformational entropy of the chain is affected by geometric confinement. It means that the wall exerts a repulsive force on the chain, resulting in accelerated link detachment from a macroscopic perspective. In this work, we investigate the effect of entropy on the detachment rate in the case where the substrate is spherical. We demonstrate that spherical confinement accelerates chain detachment both inside and outside the sphere. An analytical expression for the mean detachment time of breakable links is given, which includes an additional pre-factor that is related to the partition function. Additionally, we analyze the expressions for entropic forces inside the sphere, outside the sphere, and on a flat wall, comparing their magnitudes to explain the difference in mean detachment time.

关键词： Polymer detachment Breakable link Entropic force Mean first passage time

Three-dimensional stress variation characteristics in deep hard rock of CJPL-Ⅱ project based on in-situ monitoring

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International Journal of Mining Science and Technology 2024年第2期34卷 179-195页

作者： Minzong zheng Shaojun li Zejie Feng Huaisheng xu Yaxun Xiao State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensive examination through laboratory tests and numerical simulations, its validation through insitu stress tests remains unexplored. This study analyzes the three-dimensional stress changes in the surrounding rock at various depths, monitored during the excavation of B2 Lab in China Jinping Underground Laboratory Phase Ⅱ(CJPL-Ⅱ). The investigation delves into the three-dimensional stress variation characteristics in deep hard rock, encompassing stress components and principal stress. The results indicate changes in both the magnitude and direction of the principal stress during tunnel excavation. To quantitatively describe the degree of stress disturbance, a series of stress evaluation indexes are established based on the distances between stress tensors, including the stress disturbance index(SDI), the principal stress magnitude disturbance index(SDIm), and the principal stress direction disturbance index(SDId). The SDI indicates the greatest stress disturbance in the surrounding rock is 4.5 m from the tunnel wall in B2 Lab. SDIm shows that the principal stress magnitude disturbance peaks at2.5 m from the tunnel wall. SDId reveals that the largest change in principal stress direction does not necessarily occur near the tunnel wall but at a specific depth from it. The established relationship between SDI and the depth of the excavation damaged zone(EDZ) can serve as a criterion for determining the depth of the EDZ in deep hard rock engineering. Additionally, it provides a reference for future construction and support considerations.

关键词： Disturbance stress Tensor distance Stress disturbance index Principal stress direction Underground research laboratory

On the encounter desorption of hydrogen atoms on an ice mantle

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Research in Astronomy and Astrophysics 2021年第2期21卷 113-120页

作者： Qiang Chang xu-li zheng Xia Zhang Dong-Hui Quan Yang Lu Qing-Kuan Meng Xiao-Hu li Long-Fei Chen School of Physics and Optoeletronic Engineering Shandong University of TechnologyZibo 255000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Department of Chemistry Eastern Kentucky UniversityRichmondKY 40475USA School of Physics&Astronomy Sun Yat-Sen UniversityZhuhai 519082China

At low temperatures(10 K),hydrogen atoms can diffuse quickly on grain ice mantles and frequently encounter hydrogen molecules,which cover a notable fraction of grain *** desorption energy of H atoms on H2 substrates is much less than that on water *** H atom encounter desorption mechanism is adopted to study the enhanced desorption of H atoms on H_(2 )*** a small reaction network,we show that the steady-state surface H abundances predicted by the rate equation model that includes H atom encounter desorption agree reasonably well with the results from the more rigorous microscopic Monte Carlo *** a full gas-grain model,H atom encounter desorption can reduce surface H ***,if a model adopts the encounter desorption of H atoms,it becomes more difficult for hydrogenation products such as methanol to form,but it is easier for C,O and N atoms to bond with each other on grain surfaces.

关键词： astrochemistry-ISM abundances-ISM molecules

HCRVD: A Vulnerability Detection System Based on CST-PDG Hierarchical Code Representation Learning

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Computers, Materials & Continua 2024年第6期79卷 4573-4601页

作者： Zhihui Song Jinchen xu Kewei li zheng Shan School of Cyberspace Security Information Engineering UniversityZhengzhou450001China

Prior studies have demonstrated that deep learning-based approaches can enhance the performance of source code vulnerability detection by training neural networks to learn vulnerability patterns in code ***,due to limitations in code representation and neural network design,the validity and practicality of the model still need to be ***,due to differences in programming languages,most methods lack cross-language detection *** address these issues,in this paper,we analyze the shortcomings of previous code representations and neural *** propose a novel hierarchical code representation that combines Concrete Syntax Trees(CST)with Program Dependence Graphs(PDG).Furthermore,we introduce a Tree-Graph-Gated-Attention(TGGA)network based on gated recurrent units and attention mechanisms to build a Hierarchical Code Representation learning-based Vulnerability Detection(HCRVD)*** system enables cross-language vulnerability detection at the *** experiments show that HCRVD surpasses many competitors in vulnerability detection *** benefits from the hierarchical code representation learning method,and outperforms baseline in cross-language vulnerability detection by 9.772%and 11.819%in the C/C++and Java datasets,***,HCRVD has certain ability to detect vulnerabilities in unknown programming languages and is useful in real open-source *** shows good validity,generality and practicality.

关键词： Vulnerability detection deep learning CST-PDG code representation tree-graph-gated-attention network cross-language

Unconventional Fluorescent and Multi-responsive Polysiloxane:Synthesis,Characterization and Biological Applications

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Chinese Journal of Polymer Science 2024年第5期42卷 579-590,I0006页

作者： Xiao-Di li Shu-Sheng li xu-Bao Jiang Xiao-li Zhu Xiang zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China College of Chemical Engineering Tianjin UniversityTianjin300072China Foshan(Southern China)Institute for New Materials Foshan528200China

Owing to their high significance in fundamental study and diverse applications,stimuli-responsive and fluorescent polymers,particularly those with cluster-triggered emission(CTE)featured by non-conjugated chromophores,have drawn tremendous attention in recent *** this work,fluorescent and multi-responsive polysiloxane(FRPS)was synthesized by hydrolytic condensation polymerization of 3-aminopropyl methyl diethoxysilane(APMS)with 3-(N-isopropyl propionamide)iminopropyl methyl diethoxysilane(APMS-NIP),which was formed in situ through aza-Michael addition between APMS and N-isopropyl *** was not only highly sensitive to temperature,pH and CO_(2) in water,but also showed an enhanced and stimuli-adjustable fluorescence *** effects of monomer feeding,pH and CO_(2) on its lower critical solution temperature and fluorescent property were *** fluorescence emission was ascribed to CTE *** addition,FRPS was shown to be highly potential as physiological indicator for cell imaging,and for controlled release and trace detection of *** study provides therefore a type of stimuli-responsive and fluorescent material for potential applications in biomedical fields,and it is also of great significance for understanding of the fluorescence mechanism of polysiloxane-based stimuli-responsive polymers.

关键词： Polysiloxane Multi-responsiveness Cluster-triggered emission Cell imaging Controlled drug release