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Mathematical Analysis on a General Delayed HBV Model with Capsids and Two Infection Routes

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 508-525页

作者： li-li liU Hong-gang WANG Ya-zhi li Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention Complex Systems Research CenterShanxi UniversityTaiyuan 030006China School of Mathematics and Statistics Qiannan Normal University for NationalitiesDuyun 558000China

Considering that HBV belongs to the DNA virus family and is hepatotropic,we model the HBV DNA-containing capsids as a *** this paper,a delayed HBV infection model is established,where the general incidence function and two infection routes including cell-virus infection and cell-cell infection are *** to some preliminaries,including well-posedness,basic reproduction number and existence of two equilibria,we obtain the threshold dynamics for the *** illustrate numerical simulations to verify the above theoretical results,and furthermore explore the impacts of intracellular delay and cell-cell infection on the global dynamics of the model.

关键词： delayed HBV model capsids general incidence function two infection routes global stability

Effect of short neuropeptide F signaling on larval feeding in Mythimna separata

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Insect Science 2024年第2期31卷 417-434页

作者： Mei-Mei li Qi Yang li-Hui Chen Yan-Ying li Jun-xiang Wu xiang-li Xu State Key Laboratory of Crop Stress Biology in Arid Areas College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi ProvinceChinaand School of Agricultural Sciences Jiangxi Agricultural UniversityNanchangChina

Mythimna separata is a notorious phytophagous pest which poses serious threats to cereal crops owing to the gluttony of the *** short neuropeptide F(sNPF)and its receptor sNPFR are involved in a diversity of physiological functions,especially in functions related to feeding in insects,it is a molecular target for pest ***,an sNPF and 2 sNPFRs were identified and cloned from *** analysis revealed that the sNPF and its receptors had a highly conserved RLRFamide C-terminus and 7 transmembrane domains,*** sNPF and its receptor genes were distributed across larval periods and tissues,but 2 receptors had distinct expression *** starvation-induced assay elucidated that sNPF and sNPFR expression levels were downregulated under food deprivation and recovered with subsequent *** interference knockdown of sNPF,sNPFR1,and sNPFR2 by injection of double-stranded RNA into larvae not only suppressed food consumption and increased body size and weight,but also led to decrease of glycogen and total lipid contents,and increase of trehalose compared with double-stranded green fluorescent protein ***,molecular docking was performed on the interaction mode between sNPFR protein and its ligand sNPF based on the 3-dimensional models constructed by AlphaFold;the results indicated that both receptors were presumably activated by the mature peptide *** results revealed that sNPF signaling played a considerably vital role in the feeding regulation of *** and represents a potential control target for this pest.

关键词： feeding regulation Mythimna separata pest control target RNA interference short neuropeptide F sNPF receptors

A Novel Synthesis Route of [1 ,2,5]Oxadiazolo [3,4-e] [ 1,2,3,4]tetrazine-4,6-Di-N-oxide

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含能材料 2013年第1期21卷 131-132页

作者： WANG Bo-zhou li xiang-zhi li Hui HUO Huan ZHOU Yan-shui FAN Xue-zhong li Ji-zhen Xi'an Modern Chemistry Research Institute Xi'an 710065 China

1 Introduction An energetic material,[1,2,5] oxadiazolo [3,4-e][1,2,3,4] tetrazine-4,6-di-N-oxide (FTDO),whose density (tested) was 1.85 g · cm-3[2],enthalpy of formation was 1010 kcal· kg-1[3],calculated detonation velocity pressure was 9802 m · s-1,and detonation pressure was 44.78 GPa,was firstly synthesized and reported by Russian scientists in 1995[1].The five-step synthetic route of FTDO,which was synthesized from 3,4-diaminofurazan (DAF) via the reactions of oxidation,amino protection,condensation,hydrolysis and cyclization with a total yield of 14.63％,had been reported [1].

关键词：含能材料材料学研究理论

Dynamic Sulfur-Rich Polymers from Elemental Sulfur and Epoxides

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Chinese Journal of Polymer Science 2024年第10期42卷 1479-1487,I0010页

作者： Ke-xiang Chen Chen-Hui Cui Zhen li Ting Xu Hao-Qing Teng zhi-Yuan He Yin-Zhou Guo Xiao-Qing Ming zhi-Shen Ge Yan-Feng Zhang Tie-Jun Wang School of Chemistry Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an710049China State Key Lab for Strength and Vibration of Mechanical Structures Department of Engineering MechanicsXi’an Jiaotong UniversityXi’an710049China

Sulfur-containing dynamic polymers had attracted significant attention due to their unique chemical structures with high *** sulfur, an inexpensive industrial waste product, to synthesize dynamic polysulfide polymers through reverse vulcanization has been a notable approach. However, this method required high temperatures and resulted in the release of unpleasant oders. In this study, we presented a robust method for the preparation of sulfur-rich polymers with dynamic polysulfide bonds from elemental sulfur and inexpensive epoxide monomers via a one-pot strategy at the mild room temperature. Different types of polysulfide molecules and polymers were synthesized by reacting various epoxide compounds with sulfur, along with the investigation of their structures and dynamic behaviors. It was noteworthy that the obatined polymers prepared from m-(2,3-epoxypropoxy)-N,N-bis(2,3-epoxypropyl)aniline and elemental sulfur exhibit multiple dynamic behaviors, including polysulfide metathesis and polysulfide-thiol exchange, enabling their rapid stress relaxation, self-healing, reprocessing and degradable properties of the cross-linked polymer. More importantly, the hydroxyl groups at the side chains from epoxide ring opening exhibited potential transesterification. This work provided a facile strategy for designing dynamic sulfur-rich polymers via a mild synthesis route.

关键词： Elemental sulfur Sulfur-containing polymer Dynamic covalent bond Dynamic polymer

Removal of Cr(Ⅵ)by glutaraldehyde-crosslinked chitosan encapsulating microscale zero-valent iron:Synthesis,mechanism,and longevity

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Journal of Environmental Sciences 2024年第8期142卷 115-128页

作者： Yijun Duan Fang liu xiang liu Miao li School of Environment Tsinghua UniversityBeijing 100084China Transportation Institute of Inner Mongolia University Hohhot 010070China

Microscale zero-valent iron(mZVI)has shown great potential for groundwater Cr(Ⅵ)***,low Cr(Ⅵ)removal capacity caused by passivation restricted the wide use of *** prepared mZVI/GCS by encapsulating mZVI in a porous glutaraldehydecrosslinked chitosan matrix,and the formation of the passivation layer was alleviated by reducing the contact between zero-valent iron *** average pore diameter of mZVI/GCS was 8.775 nm,which confirmed the mesoporous characteristic of this *** of batch experiments demonstrated that mZVI/GCS exhibited high Cr(Ⅵ)removal efficiency in a wide range of pH(2-10)and temperature(5-35℃).Common groundwater coexisting ions slightly affected m ZVI/*** material showed great reusability,and the average Cr(Ⅵ)removal efficiency was 90.41%during eight *** this study,we also conducted kinetics and isotherms ***-second-order model was the most matched kinetics *** Cr(Ⅵ)adsorption process was fitted by both Langmuir and Freundlich isotherms models,and the maximum Langmuir adsorption capacity of m ZVI/GCS reached243.63 mg/g,which is higher than the adsorption capacities of materials reported in most of the previous ***,the column capacity for Cr(Ⅵ)removal of a mZVI/GCS-packed column was 6.4 times higher than that of a mZVI-packed column in a 50-day ***,mZVI/GCS with a porous structure effectively relieved passivation problems of mZVI and showed practical application prospects as groundwater Cr(Ⅵ)remediation material with practical application prospects.

关键词： Chitosan Glutaraldehyde mZVI Cr(Ⅵ) Groundwater

Association of Thyroid Nodules with Various Elements in Urine and Blood Serum: A Case-Control Study

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Biomedical and Environmental Sciences 2024年第3期37卷 320-324页

作者： li xiang zhi WU Cai lian CEN li Ting HUANG Ming Le HUANG Min Min QIU Mei Ting LU Xiao ling Guangxi Key Laboratory on Precise Prevention and Treatment for Thyroid Tumor The Second Affiliated Hospital of Guangxi University of Science and TechnologyGuangxi University of Science and TechnologyLiuzhou 545006GuangxiChina Department of Public Health School of MedicineGuangxi University of Science and TechnologyLiuzhou 545005GuangxiChina Academic and Research Department The Second Affiliated Hospital of Guangxi University of Science and TechnologyGuangxi University of Science and TechnologyLiuzhou 545006GuangxiChina

Thyroid nodules are a common clinical problem caused by various factors,including environmental and nutritional factors and genetic *** environment can modulate and influence not only the risk of thyroid nodules but also the severity of disease in humans[1].The environment is awash with elements,and all mineral elements,including heavy metals and trace elements,are considered potentially toxic.A significantly higher incidence of thyroid cancer has been reported in populations exposed to low doses of metallic elements in volcanic areas over a long period[2].As research on thyroid disorders continues,it is becoming clear that abnormalities in trace elements in the body can affect the development of thyroid-related disorders.

关键词： Blood doses Serum

Reinforcing oxygen electrocatalytic activity via selective dualphase heterointerface engineering for rechargeable Zn-air batteries

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Rare Metals 2024年第4期43卷 1524-1536页

作者： Chao Cheng Chuang zhi Zhong-Ti Sun Yong-Qiang Ming Ting-Ting xiang Qing-Chao Zhu Zi-Rui Wu Bing li Yi li Cheng Jin Yong Cao Juan Yang School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming650093China

Dual-phase heterointerface electrocatalysts(DPHE)constructed by oxygen reduction reaction(ORR)-and oxygen evolution reaction(OER)-active elements exhibit excellent bifunctional activity and long-term durability due to the abundant interface exposure and synergistic catalytic ***,low-dimensional N-doped graphene nanoribbons(N-GNRs)coupling with ultrathin CoO nanocomposites(N-GNRs/CoO)were controllably fabricated through a facile two-step approach using synthesized Co(OH)_2 nanosheet as CoO *** functional theory(DFT)calculations and experimental characterizations prove that the formation of interface between N-GNRs and CoO can induce local charge redistribution,contributing to the improvement of catalytic activity and *** optimal N-GNRs/CoO DPHE possesses hierarchically porous architectures and presents outstanding bifunctional activities with a small potential gap of 0.729 V between the potential at 10 mA·cm^(-2)for OER and the halfwave potential for ORR,which outperforms Pt/C+IrO_(2)and the majority of noble-metal-free bifunctional ***-and solid-state rechargeable Zn-air batteries assembled with N-GNRs/CoO as the cathode also display high peak power density and fantastic cycle stability,superior to that of benchmark Pt/C+IrO_(2)*** is anticipated to offer significant benefits toward high activity,stability and mechanical flexibility bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries.

关键词： Interface engineering Graphene nanoribbons CoO Bifunctional electrocatalyst Zn-air batteries

Distortion-aware beamforming design for multi-beam satellite communications with nonlinear power amplifiers

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Science China(Information Sciences) 2024年第6期67卷 359-369页

作者： xiang XIAO li YOU Kezhi WANG Xiqi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Computer Science Brunel University London

Hardware components can cause different impairments, including power amplifier(PA) nonlinearities, which inevitably impact the system performance of satellite communications(SATCOM). In this work, we consider a multi-beam SATCOM downlink system and investigate the distortion-aware beamforming scheme with the characteristics of PA non-linearities. Notably, we aim to maximize the resource efficiency(RE), defined as the weighted sum of energy efficiency(EE) with spectral efficiency(SE), to obtain a flexible EE-SE tradeoff while accounting for the characteristics of PA distortion and the total power *** that the optimization objective is a sum of ratios and the high non-convexity involved in constraints,we propose an efficient approach that exploits the quadratic transformation, the Lagrange multiplier method,and the gradient ascent approach to handle this issue. Simulation results demonstrate the effectiveness of the distortion-aware beamforming approach in achieving the EE-SE tradeoff and exhibit a substantial RE performance gain over the conventional approach with ideal linear PAs assumed at the satellite transmitters.

关键词： multi-beam satellite communications nonlinear power amplifier energy and spectral efficiency tradeoff resource efficiency robust beamforming

Flocking of a Cucker–Smale Type Model with Compactly Supported Interaction Functions

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2285-2296页

作者： Chun Yin JIN Shuang zhi li College of Science China Agricultural UniversityBeijing 100083P.R.China

How to analyze flocking behaviors of a multi-agent system with local interaction functions is a challenging problem in *** and Tadmor in 2011 also stressed the significance to assume that the interaction function is rapidly decaying or cut-off at a finite distance(*** and Tadmor in ***.2011).In this paper,we study the flocking behavior of a Cucker–Smale type model with compactly supported interaction *** properties of a connected stochastic matrix,together with an elaborate analysis on perturbations of a linearized system,we obtain a sufficient condition imposed only on model parameters and initial data to guarantee ***,it is shown that the system achieves flocking at an exponential rate.

关键词： Cucker-Smale model local interaction flocking stochastic matrix neighbor graph