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Journal of Forestry Research 2021年第5期32卷 2219-2226页

作者： Qiqiang Guo Huie Li Zengqiang Qian Jie Lu Weilie zheng Institute for Forest Resources&Environment of Guizhou/College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China College of Agriculture Guizhou UniversityGuiyang 550025People’s Republic of China College of Life Sciences Shaanxi Normal UniversityXi’an 710062People’s Republic of China Key Laboratory of Forest Ecology in Tibet Plateau(Tibet Agriculture&Animal Husbandry University) Ministry of EducationNyingchi 860000TibetPeople’s Republic of China Institute of Tibet Plateau Ecology Tibet Agriculture&Animal Husbandry UniversityNyingchi 860000TibetPeople’s Republic of China

Five Larix species(***,***,***,***,and *** ***),have survived on the Qinghai-Tibet Plateau(QTP)under specific climate conditions for *** lack of genomic information seriously hinders research on the evolution,conservation and ecology of these Larix *** this study,complete chloroplast(cp)genomes of the 5 species were assembled and compared based on next generation sequencing technology combined with polymerase chain reaction *** results show that the 5 cp genomes are relatively conservative in size,gene content and arrangement,and border *** analysis showed that the species are closely related as well as to seven other species of the same *** addition,the 5 cp genomes contained few simple sequence repeats and relatively low nucleotide variability;thus,12 candidate polymorphic cp DNA markers will be helpful for further research on relevant population *** results will provide valuable genetic information for the conservation,evolution and ecology of these species and their relatives.

关键词： Larix species Plastid genome Microsatellite Phylogenetic analysis Qinghai-tibet plateau

Drug target discovery by magnetic nanoparticles coupled mass spectrometry

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Journal of Pharmaceutical Analysis 2021年第1期11卷 122-127页

作者： Dandan Xia Baoling Liu Xiaowei Xu Ya Ding Qiuling zheng Department of Pharmaceutical Analysis School of PharmacyChina Pharmaceutical UniversityNanjing210009China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing210009China Key Laboratory of Drug Metabolism and Pharmacokinetics China Pharmaceutical UniversityNanjing210009China

Drug target discovery is the basis of drug *** elucidates the cause of disease and the mechanism of drug action,which is the essential of drug *** discovery performed in biological systems is complicated as proteins are in low abundance and endogenous compounds may interfere with drug ***,methods to track drug-target interactions in biological matrices are urgently *** this work,a Fe_(3)O_(4) nanoparticle-based approach was developed for drug-target screening in biofluids.A known ligand-protein complex was selected as a principle-to-proof example to validate the *** incubation in cell lysates,ligand-modified Fe_(3)O_(4) nanoparticles bound to the target protein and formed complexes that were separated from the lysates by a magnet for further *** large surface-to-volume ratio of the nanoparticles provides more active sites for the modification of chemical *** enhances the opportunity for ligand-protein interactions,which is beneficial for capturing target proteins,especially for those with low ***,a one-step magnetic separation simplifies the pre-processing of ligand-protein complexes,so it effectively reduces the endogenous ***,the present nanoparticle-based approach has the potential to be used for drug target screening in biological systems.

关键词： Drug-target discovery Nanoparticle Mass spectrometry

Novel diagnostic imaging techniques and applications in anterior uveitis,intermediate uveitis,and scleritis

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Annals of Eye Science 2020年第3期5卷 11-18页

作者： Andrew zheng Sumit Sharma Cole Eye Institute Cleveland Clinic FoundationClevelandOHUSA

Uveitis can cause significant visual morbidity and often affects younger adults of working *** uveitis,or inflammation limited to the anterior chamber(AC),iris,and/or ciliary body comprises the majority of uveitis *** clinical biomarkers and conventional grading scales for intraocular inflammation are mostly subjective and have only a moderate degree of interobserver reliability,and as such they have significant limitations when used in either clinical practice or research related to *** recent years,novel imaging techniques and applications have emerged that can supplement exam findings to detect subclinical disease,monitor quantitative biomarkers of disease progression or treatment effect,and provide overall a more nuanced understanding of disease *** first part of this review discusses automated algorithms for optical coherence tomography(OCT)image processing and analysis as a means to assess and describe intraocular inflammation with higher resolution than that afforded by conventional AC and vitreous cell ordinal grading *** second half of the review focuses on anterior segment OCT and OCT angiography(OCTA)in scleritis and iritis,especially with regards to their ability to directly image and characterize the pathologic structures and vasculature underlying these ***,we briefly review experimental animal research with promising but more distant human clinical applications,including in vivo molecular microscopy of inflammatory markers and investigation of gold nanoparticles as a potential contrast agent in OCT *** modalities are discussed in the broader context of trends within the field of uveitis towards greater objectivity and quantifiable outcome measures and biomarkers.

关键词： Uveitis scleritis ophthalmological diagnostic techniques

THE EFFECT OF BLENDING SEQUENCE ON PHASE MORPHOLOGY OF NYLON 6/ABS/SMA BLENDS

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Chinese Journal of Polymer Science 2008年第1期26卷 73-80页

作者： Qin, Shu-Hao Yu, Jie zheng, Qiang He, Min Zhu, Hong Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China Natl Engn Res Ctr Compounding & Modificat Polymer Guiyang 550025 Peoples R China

The preparation process-dependent phase morphology of blends composed of nylon 6 and acrylonitrile-butadiene- styrene(ABS)over a composition range of 30-70 wt% using a styrene-maleic anhydride(SMA)copolymer as the compatibilizing agent with a constant content(5phr)was *** results of the scanning electron microscope (SEM)observation revealed that compared with the binary blends of nylon 6 and ABS,the existence of SMA caused a composition shift of phase inversion to a higher weight fraction of ny...

关键词： Nylon 6 ABS Morphology Blending sequence Dynamic mechanical properties

1,2,5,6-Naphthalene Diimides:A Class of Promising Building Blocks for Organic Semiconductors

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Chinese Journal of Chemistry 2023年第10期41卷 1226-1234页

作者： zheng Zhao Congwu Ge Xueqian Zhao Jintao Huang Xike Gao Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

Organic semiconductors have drawn extensive atten-tion due to their optoelectronic properties and wide applications in organic *** comparison with the popular 1,4,5,8-naphthalene diimides(1,4,5,8-NDIs),the angular-shaped 1,2,5,6-NDIs have exhibited tunable photophysical properties,self-as-sembly behaviors and charge transporting *** to these unique features,1,2,5,6-NDIs show great potential for construction of high performance n-func-tional *** this review,we highlight the recent advances and future prospects of 1,2,5,6-NDI-basedπ-systems in the field of organic optoelectronics,in-cluding molecular design,synthesis,structure-prop-erty relationships as well as the applications in high performance organic field-effect transistors,organic photovoltaics,perovskite solar cells,and so on.

关键词： Organic semiconductors Electron acceptors Design and synthesis 1,2,5,6-NDI Structural isomerism Polymer acceptors Organic electronics

Unsteady heat and mass transfer in MHD flow over an oscillatory stretching surface with Soret and Dufour efects

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Acta Mechanica Sinica 2013年第5期29卷 667-675页

作者： Lian-Cun zheng Xin Jin Xin-Xin Zhang Jun-Hong Zhang School of Mathematics and Physics University of Science and TechnologyBeijing School of Mechanical Engineering University of Science and Technology Beijing Naval University of Engineering

In this paper, we study the unsteady coupled heat and mass transfer of two-dimensional MHD fluid over a moving oscillatory stretching surface with Soret and Dufour effects. Viscous dissipation effects are adopted in the energy equation. A uniform magnetic field is applied vertically to the flow direction. The governing equations are reduced to non-linear coupled partial differential equations and solved by means of homotopy analysis method （HAM）. The effects of some physical parameters such as magnetic parameter, Dufour number, Soret number, the Prandtl num- ber and the ratio of the oscillation frequency of the sheet to its stretching rate on the flow and heat transfer characteristics are illustrated and analyzed.

关键词： Viscous conducted fluid Magnetic field Os- cillatory stretching surface Heat and mass transfer HAM solution

Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach

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China Communications 2024年第5期21卷 77-96页

作者： Zhao Di zheng Zhong Qin Pengfei Qin Hao Song Bin State Key Laboratory of Integrated Services Networks Xidian University710071China China Academy of Space Technology Beijing 100081China

To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing *** this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user *** first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)***,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource *** results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance.

关键词： dynamic resource allocation multi-user cellular network spectrum efficiency user fairness

PER2-mediated ameloblast differentiation via PPARγ/AKT1/β-catenin axis

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International Journal of Oral Science 2021年第2期13卷 190-199页

作者： Wushuang Huang Xueqing zheng Mei Yang Ruiqi Li Yaling Song The State Key Laboratory Breeding Base of Basic Science of Stomatology(Hubei-MOST)and Key Laboratory of Oral Biomedicine Ministry of Education School and Hospital of StomatologyWuhan UniversityWuhanChina

Circadian rhythm is involved in the development and diseases of many ***,as an essential environmental regulating factor,its effect on amelogenesis has not been fully *** present study aims to investigate the correlation between circadian rhythm and ameloblast differentiation and to explore the mechanism by which circadian genes regulate ameloblast *** disruption models were constructed in mice for in vivo *** ameloblast-lineage cell(ALC)line was used for in vitro *** essential molecules of the circadian system,Bmal1 and Per2 exhibited circadian expression in *** disruption mice showed reduced amelogenin(AMELX)expression and enamel matrix secretion and downregulated expression of BMAL1,PER2,PPARγ,phosphorylated AKT1 andβ-catenin,cytokeratin-14 and F-actin in *** to previous findings and our study,BMAL1 positively regulated ***,the present study focused on PER2-mediated ameloblast differentiation and enamel ***2 knockdown decreased the expression of AMELX,PPARγ,phosphorylated AKT1 andβ-catenin,promoted nuclearβ-catenin accumulation,inhibited mineralization and altered the subcellular localization of E-cadherin in *** of PPARγpartially reversed the above results in Per2-knockdown ***,in in vivo experiments,the length of incisor eruption was significantly decreased in the circadian disturbance group compared to that in the control group,which was rescued by using a PPARγagonist in circadian disturbance *** conclusion,through regulation of the PPARγ/AKT1/β-catenin signalling axis,PER2 played roles in amelogenin expression,cell junctions and arrangement,enamel matrix secretion and mineralization during ameloblast differentiation,which exert effects on enamel formation.

关键词： PER2 inhibited AKT1

A new multiple-factor clustering method considering both box fractal dimension and orientation of joints

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第2期14卷 366-376页

作者： Tiexin Liu Annan Jiang Jianhui Deng Jun zheng zhenghu Zhang Department of Civil Engineering Dalian Maritime UniversityDalian116026China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource&HydropowerSichuan UniversityChengdu610065China Department of Civil Engineering Zhejiang UniversityHangzhou310058China State Key Laboratory of the Coastal and Offshore Engineering School of Civil EngineeringDalian University of TechnologyDalian116024China

The paper proposes a new multiple-factor clustering method(NMFCM)with consideration of both box fractal dimension(BFD)and orientation of *** method assumes that the BFDs of different clusters were uneven,and clustering was performed by redistributing the joints near the boundaries of clusters on a polar map to maximize an index for estimating the difference of the BFD(DBFD).Three main aspects were studied to develop the ***,procedures of the NMFCM and reasonableness of assumptions were ***,main factors affecting the NMFCM were investigated by numerical simulations with disk joint ***,two different sections of a rock slope were studied to verify the practicability of the *** results demonstrated that:(1)The NMFCM was practical and could effectively alleviate the problem of hard boundary during clustering;(2)The DBFD tended to increase after the improvement of clustering accuracy;(3)The improvement degree of the NMFCM clustering accuracy was mainly influenced by three parameters,namely,the number of clusters,number of redistributed joints,and total number of joints;and(4)The accuracy rate of clustering could be effectively improved by the NMFCM.

关键词： Joint clustering Box fractal dimension(BFD) Orientation Hard boundary

Visible-light-driven photocatalytic inactivation of bacteriophage f2 by Cu-TiO_2 nanofibers in the presence of humic acid

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Journal of Environmental Sciences 2019年第3期31卷 383-391页

作者： Rong Cheng Mi Kang Zhi-peng Shen Lei Shi Xiang zheng School of Environment & Natural Resources Renmin University of China

Pathogenic viruses in drinking water are great threats to public health. Visible-lightdriven photocatalysis is a promising technology for virus inactivation. However, the existing photocatalytic antiviral research studies have mostly been carried out in single-component systems, neglecting the effect of natural organic matter, which exists widely in actual water bodies. In this paper, electrospun Cu-TiO2 nanofibers were prepared as photocatalysts, and their photocatalytic antiviral performance in the presence of humic acid(HA) was comprehensively studied for the first time. The properties of the reaction mixture were measured during the reaction. In addition, the safety, reliability and stability of photocatalytic disinfection in the mixed system were evaluated. The results showed that the virus removal efficiency decreased with the increase of the HA concentration. The type of reaction solution, such as PBS buffer solution or water, did not affect the removal efficiency noticeably. Under acidic conditions, the electrostatic forces between photocatalysts and viruses were strengthened, leading to higher virus removal efficiency. As the reaction time went on, the pH value in the solution increased first and then tended to be stable, the conductivity remained stable, and the dissolved oxygen increased first and then decreased. The safety test showed that the concentration of Cu ions released into the solution was lower than specified by the international standards. No photoreactivation was observed, and the addition of HA significantly reduced the reutilization efficiency of the photocatalysts.

关键词： Photocatalysis Visible light Bacteriophage f2 Humic acid