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Strategies for the development and approval of COVID-19 vaccines and therapeutics in the post-pandemic period

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Signal Transduction and Targeted Therapy 2024年第1期9卷 19-35页

作者： Danyi ao Xuemei He Jian liu Li Xu State Key Laboratory of Biotherapy West China HospitalSichuan University610041 SichuanPeople’s Republic of China

The spread of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in significant casualties and put immense strain on public health systems worldwide,leading to economic recession and social *** response,various prevention and control strategies have been implemented globally,including vaccine and drug development and the promotion of preventive *** these strategies has effectively curbed the transmission of the virus,reduced infection rates,and gradually restored normal social and economic ***,the mutations of SARS-CoV-2 have led to inevitable infections and reinfections,and the number of deaths continues to ***,there is still a need to improve existing prevention and control strategies,mainly focusing on developing novel vaccines and drugs,expediting medical authorization processes,and keeping epidemic *** measures are crucial to combat the Coronavirus disease(COVID-19)pandemic and achieve sustained,long-term prevention,management,and disease ***,we summarized the characteristics of existing COVID-19 vaccines and drugs and suggested potential future directions for their ***,we discussed the COVID-19-related policies implemented over the past years and presented some strategies for the future.

关键词： prevention sustained approval

Flavor mixing and solution structures in Dyson–Schwinger equations for a two-flavor system

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Communications in Theoretical Physics 2024年第10期76卷 64-77页

作者： Xue-ao Chao Yu-xin liu Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Collaborative Innovation Center of Quantum Matter Center for High Energy Physics Peking University

We solved the Dyson–Schwinger(DS) equations for a two-flavor system with symmetry to study its flavor mixing effects. Initially, we employed the point interaction model and bare vertex approximation to reveal the structure of the solutions. Using the point interaction model, the DS equations can be solved analytically, and we found that these solutions can be classified into three groups, each forming an ellipse. These solutions exhibit SO(2) symmetry, while the original SU(2)symmetry at the Lagrangian level is dynamically broken to SO(2), corresponding to the emergence of flavor mixing effects. However, this flavor mixing effect does not manifest in the final physical *** utilizing the system's SO(2) symmetry, we can diagonalize the propagators of the DS equations,eliminating the flavor mixing effect but causing the originally degenerate masses at the Lagrangian level to split. These mass eigenstates have identical quantum numbers but different masses. If we can correspond these to quark particles of different generations, we can explain why the three generations of quarks have different masses and obtain the corresponding quark mass spectrum. Finally, we provide the corresponding numerical results using a more realistic interaction model.

关键词： dynamic symmetry breaking Dyson-Schwinger equation flavor change mass splitting

Polyolefin vitrimers bearing acetoacetate functionality

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Science China Chemistry 2024年第11期67卷 3861-3867页

作者： Zihao Wang Yue liu Wenmin Pang ao Chen Min Chen Chinese Academy of Sciences (CAS) Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Anhui University

Polyolefin vitrimers are polymer networks bearing reversible covalent crosslinking points, enabling them to be reprocessed and recycled. In this contribution, a series of polyolefin vitrimers were designed based on the acetoacetate-functionalized polyolefin copolymers, which were produced through the direct copolymerization of ethylene with polar comonomers using a phosphinesulfonate palladium catalyst. The pendant acetoacetate group could mediate several characteristic reactions, such as the Michael addition reaction, ketone-amine condensation and metal coordination reaction. As such, structurally adjustable polyolefin vitrimers can be accessed by introducing various dynamic crosslinking bonds, including disulfide exchange, transamination of vinylogous urethane and labile metal coordination bond. The utilization of different crosslinking reactions and the mole ratio of crosslinkers significantly impact the material properties of the resultant polymers. Specifically, the generated polyolefin vitrimers demonstrated excellent reprocessability and closed-loop recycling properties. The study in this work provides an efficient strategy to access various polyolefin vitrimers.

关键词： polyolefin vitrimers acetoacetate group polar monomer olefin copolymerization

Incombustible solid polymer electrolytes:A critical review and perspective

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Journal of Energy Chemistry 2024年第6期93卷 264-281,I0007页

作者： Kai Wu Jin Tan Zhenfang liu Chenguang Bao ao Li Qi liu Baohua Li College of Materials Science and Engineering Hunan UniversityChangsha 413000HunanChina Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 055GuangdongChina

Since the advent of the solid-state batteries,employing solid polymer electrolytes(SPEs)to replace routine flammable liquid electrolytes is regarded to be one of the most promising solutions in pursing highenergy-density battery *** with superior thermal stability,good processability,and high mechanical modulus obtain increasing ***,SPE-based batteries are not impenetrable due to their decomposition and combustibility under extreme *** believe incorporating appropriate flame-retardant additives/solvents/fragments into SPEs can intrinsically reduce their flammability to solve the battery safety *** this review,the recent research progress of incombustible SPEs,with special emphasis on flame-retardant structural design,is ***,a brief introduction of flame-retardant mechanism,evaluation index for safety of SPEs,and a detailed overview of the latest advances on diverse-types SPEs in various battery systems are *** deep insight into thermal ru naway process,the free-standing incombustible GPEs,and the ratio nal design of pouch cell structures may be the main directions to motivate revolutionary next-generation for safety batteries.

关键词： Non-flammable electrolyte Solid polymer electrolyte High safety electrolyte Solid state electrolyte Solid state battery

Europium-bearing organic framework with excellent X-ray scintillating luminescence

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Journal of Rare Earths 2024年第2期42卷 251-255,I0001页

作者： Yugang Zhang Lanhua Chen Xia Wang Wei liu Shu'ao Wang State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou215123China School of Environmental and Materials Engineering Yantai UniversityYantai264005China

Two europium-bearing organic frameworks,termed as EuTPO-1 and EuTPO-2(H_(3)TPO=tris(4-carboxylphenyI)-phosphineoxide),are reported in this work.A series of characterizations of EuTPO-1and EuTPO-2,such as X-ray crystallography and photoluminescence spectroscopy,was performed to expatiate their structure and physicochemical *** of them are constructed by dimers of the europium-oxygen subunit of [Eu_(2)O_(16)] and TPO *** from high X-ray stopping attenuation and excellent luminescence efficiency,they emit sufficient luminescence when irradiated with ***,they possess stable light outputs when exposed to high humidities and strong radiation dose,outperforming the commercial scintillator CsI:*** result paves the way for developing new scintillator and enriches the compound of europium-bearing organic framework with X-ray scintillating luminescence.

关键词： Metal-organic frameworks Scintillating material Luminescence efficiency Rare earths

Efficient piezo-assisted near-infrared-light-driven Cr(Ⅵ)reduction over Bi_(2)S_(3) nanowires transformed from ultrathin Bi_(2)WO_(6) nanosheets

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Rare Metals 2024年第9期43卷 4333-4343页

作者： Qiang Zhang Yuan-Hao Cheng Wei liu Hui-Nan Che Yan-Hui ao Key Laboratory of Integrated Regulation and Resource Development On Shallow Lakes Ministry of EducationCollege of EnvironmentHohai UniversityNanjing 210098China

The utilization of piezo-photocatalytic technol ogy for environmental remediation under full spectrum solar light is promising but still ***,one dimensional Bi_(2)S_(3)nanowires,which can utilize both mechanical energy and near-infrared(NIR)light to remov hexavalent chromium(Cr(Ⅵ))efficiently,were synthe sized by a restrained growth *** reaction rat constants of Cr(Ⅵ)reduction in piezo-photocatalyti process under NIR(800–2500 nm)reached 0.334 min^(-1)which were 3.2.and 12.4 times as that of single piezo and photocatalytic *** formation of polarized electri fields and one-dimensional structure allow ultrafast sepa ration of charge carriers,thereby promoting the catalyti ***,due to the strong penetrability o NIR light,the piezo-photocatalysis performance in turbid solutions under NIR light(0.188 min^(-1))was even com parable to that under visible light(0.186 min^(-1)).Thi study provides a new concept on the development of piezo photocatalytic technology for environmental remediation by utilization of NIR light and natural mechanical energy.

关键词： Piezo-photocatalysis NIR light Bi_(2)S_(3)nanowires Cr(Ⅵ)

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2A tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2A Team Southwestern Institute of Physics Chengdu 610041People's Republic of China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2A *** 20-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2026 mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 122 nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~280 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2A campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

Elaborative collection of condensed combustion products of solid propellants:Towards a real Solid Rocket Motor(SRM)operational environment

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Chinese Journal of Aeronautics 2024年第1期37卷 77-88页

作者： Wenchao ZHANG Zhimin FAN Dongliang GOU Yao SHU Peijin liu Aimin PANG Wen ao National Key Laboratory of Solid Rocket Propulsion Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Aerospace Chemical Power Laboratory Xiangyang 441003China

A novel constant-pressure and constant-quenching distance Condensed Combustion Products(CCPs)collection system was developed,coupled with a timing control system,to collect the CCPs formed in the course of burning of aluminum-based composite *** effects of adiabatic graphite plating,collection zone,quenching distance,time series of collection,and propellant burning rate on the microscopic morphology,particle size distribution and unburned aluminum content of CCPs were *** was verified that the graphite plating can provide a high-fidelity high-temperature environment for propellant *** combustion efficiency is improved by 2.44% compared to the bare propellant *** time series of collection has a significant effect on the combustion efficiency of aluminum,and the combustion efficiency of aluminum in the thermal state(1.2-2.4 s)is 2.75% higher than that in the cold state(0-1.2 s).Similarly,the characteristics of the CCPs in different collection zones are *** the quenching distance of 5 mm,the combustion efficiency of aluminum in the core zone(85.39%)is much lower than that in the outer zone(92.07%),while the particle size of the CCPs in the core zone(172μm)is larger than that in the outer zone(41μm).This indicates that the core zone is more likely to produce large-sized and incompletely burned agglomerates during the propellant combustion *** burning rates also lead to a significant difference in particle size distribution and combustion *** burning rates result in higher combustion efficiency.A detailed sequence of the elaborative collection process of CCPs is proposed,mainly including the setting of ignition delay time,burning rate,working pressure,plating length and time series of *** findings of this study are expected to provide a reliable tool for the evaluation of the combustion efficiency of solid propellants.

关键词： Composite propellants Condensed combustion products Aluminum Combustion efficiency Particle size distribution

Prenatal prednisone exposure disturbs fetal kidney development and its characteristics

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Journal of Environmental Sciences 2024年第11期145卷 75-87页

作者： Zhiping Xia Songdi Wang Wen Wang Yutang liu Tianshu Yang Hui Wang Ying ao Department of Pharmacology Wuhan University School of Basic Medical SciencesWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China

Prednisone is a synthetic glucocorticoid that is commonly used in both human and veterinary ***,it is also recognized as an emerging environmental *** be exposed to prednisone actively or passively throughmultiple pathways and cause developmental toxicity to the ***,the impact of prenatal prednisone exposure(PPE)on fetal kidney development remains *** this study,pregnant mice were administered prednisone intragastrically during full-term pregnancy with different doses(0.25,0.5,or 1 mg/(kg·day)),or at the dose of 1 mg/(kg·day)in different gestational days(GD)(GD0-9,GD10-18,or GD0-18).The pregnant mice were euthanized on *** staining revealed fetal kidney dysplasia,with an enlarged glomerular Bowman’s capsule space and a reduced capillary network in the PPE *** expression of the podocyte and the mesangial cell marker genes was significantly reduced in the PPE ***,overall gene expression in renal tubules and collecting ducts were markedly *** of the above effects were more pronounced in high-dose,full-term pregnancy,and female *** on the mechanism of the female fetal kidney have revealed that PPE reduced the expression of Six2,increased the expression of Hnf1β,Hnf4α,and Wnt9b,and inhibited the expression of glial cell line-derived neurotrophic factor(GDNF)and Notch signaling *** conclusion,this study demonstrated that there is a sex difference in the developmental toxicity of PPE to the fetal kidney,and the time effect is manifested as full-term pregnancy>early pregnancy>mid-late pregnancy.

关键词： Prenatal prednisone exposure Kidney developmental toxicity Glomerulus Toxicity characteristics