Surface Molecular Encapsulation with Cyclodextrin in Promoting the Activity and Stability of Fe Single-Atom Catalyst for Oxygen Reduction Reaction

Fe single-atom catalysts(Fe-SACs)have been extensively studied as a highly efficient electrocatalyst toward the oxygen reduction reaction(ORR).Nonetheless,they suffer from stability issue induced by dissolution of Fe metal center and the OH^(−)blocking.Herein,a surface molecular engineering strategy is developed by usingβ-cyclodextrins(CDs)as a localized molecular encapsulation.The CD-modified Fe-SAC(Fe-SNC-β-CD)shows obviously improved activity toward the ORR with 0.90 V,4.10 and 4.09 mA cm^(-2)for E_(1/2),J_(0)and Jk0.9,respectively.Meanwhile,the Fe-SNC-β-CD shows the excellent long-term stability against aggressive stress and the poisoning.It is confirmed through electrochemical investigation that modification ofβ-CD can,on one hand,regulate the atomic Fe coordination chemistry through the interaction between the CD and FeN_(x) moiety,while on the other mitigate the strong adsorption of OH^(−)and function as protective barrier against the poisoning molecules leading to enhanced ORR activity and stability for the Fe-SACs.The molecular encapsulation strategy demonstrates the uniqueness of post-pyrolysis surface molecular engineering for the design of single-atom catalyst.

Revolutionizing diabetic wound healing:The power of microneedles

Diabetic wounds significantly affect patient quality of life.Microneedles are a promising treatment to accelerate wound healing owing to their high drug-loading capacity and efficient drug delivery;however,few studies to date have comprehensively reviewed microneedles for diabetic wound healing.This up-to-date review summarizes the research progress in microneedles for diabetic wound healing,including manufacturing materials and techniques,structures,designs,release mechanisms,delivery substances,and their specific effects.This study showed that most microneedles designed for diabetic wounds are made of synthetic polymers and/or natural materials using polydimethylsiloxane micromolding.The geometric structure and design directly influence penetration ability and drug delivery capacity.Microneedles can deliver antibiotics,hypoglycemic agents,traditional Chinese medicines,metal ions,growth factors,exosomes,stem cells,and microorganisms,thus promoting diabetic wound healing through diverse mechanisms,such as antibacterial,anti-inflammatory,antioxidant,hypoglycemic,and angiogenic activities,at different stages of the healing process.In conclusion,microneedles are promising drug delivery systems for the treatment of diabetic wounds.

Double casing warhead with sandwiched charge:The axial distribution of fragments velocities

The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity,and the previous work has presented a calculation formula to determine the maximum fragment velocity.The current work builds on the published formula to further develop a formula for calculating the axial distribution characteristics of the fragment velocity.For this type of warhead,the simulation of the dispersion characteristics of the detonation products at different positions shows that the detonation products at the ends have a much larger axial velocity than those in the middle,and the detonation products have a greater axial dispersion velocity when they are closer to the central axis.The loading process and the fragment velocity vary with the axial position for both casing layers,and the total velocity of the fragments is the vector sum of the radial velocity and the axial velocity.At the same axial position,the acceleration time of the inner casing is greater than that of the outer casing.For the same casing,the fragments generated at the ends have a longer acceleration time than the fragments from the middle.The proposed formula is validated with the X-ray radiography results of the four warheads previously tested experimentally and the 3D smoothedparticle hydrodynamics numerical simulation results of several series of new warheads with different configurations.The formula can accurately and reliably calculate the fragment velocity when the lengthto-diameter ratio of the charge is greater than 1.5 and the thickness of the casing is less than 20%its inner radius.This work thus provides a key reference for the theoretical analysis and the design of warheads with multiple casings.

A dynamic regulation of nitrogen on floret primordia development in wheat

Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilization is largely unknown.A high temporal-resolution investigation of floret primordia number and morphology,dry matter,and N availability was conducted under three N fertilization levels:0(N0),120(N1)and 240(N2)kg ha^(−1).Interestingly,fertile florets at anthesis stage were determined by those floret primordia with meiotic ability at booting stage:meiotic ability was a threshold that predicted whether a floret primordium became fertile or abortive florets.Because the developmental rate of the 4th floret primordium in the central spikelet was accelerated and then they acquired meiotic ability,the NFFs increased gradually as N application increased,but the increase range decreased under N2.There were no differences in spike N concentration among treatments,but leaf N concentration was increased in the N1 and N2 treatments.Correspondingly,dry matter accumulation and N content of the leaf and spike in the N1 and N2 treatments was increased as compared to N0.Clearly,optimal N fertilization increased leaf N availability and transport of assimilates to spikes,and allowed more floret primordia to acquire meiotic ability and become fertile florets,finally increasing NFFs.There was no difference in leaf N concentration between N1 and N2 treatment,whereas soil N concentration at 0–60 cm soil layers was higher in N2 than in N1 treatment,implying that there was still some N fertilization that remained unused.Therefore,improving the leaf’s ability to further use N fertilizer is vital for greater NFFs.

Resist Thermal Shock Through Viscoelastic Interface Encapsulation in Perovskite Solar Cells

Enhancing the lifetime of perovskite solar cells(PSCs)is one of the essential challenges for their industrialization.Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions.However,the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging,respectively,resulting in irreversible damage to the morphology,component,and phase of stacked materials.Herein,the viscoelastic polymer polyvinyl butyral(PVB)material is designed onto the surface of perovskite films to form flexible interface encapsulation.After PVB interface encapsulation,the surface modulus of perovskite films decreases by nearly 50%,and the interface stress range under the dynamic temperature field(−40 to 85°C)drops from−42.5 to 64.8 MPa to−14.8 to 5.0 MPa.Besides,PVB forms chemical interactions with FA+cations and Pb^(2+),and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film.As a result,the optimized device's efficiency increases from 22.21%to 23.11%.Additionally,after 1500 h of thermal treatment(85°C),1000 h of damp heat test(85°C&85%RH),and 250 cycles of thermal cycling test(−40 to 85°C),the devices maintain 92.6%,85.8%,and 96.1%of their initial efficiencies,respectively.

PtNi-W/C with Atomically Dispersed Tungsten Sites Toward Boosted ORR in Proton Exchange Membrane Fuel Cell Devices

The performance of proton exchange membrane fuel cells is heavily dependent on the microstructure of electrode catalyst especially at low catalyst loadings.This work shows a hybrid electrocatalyst consisting of PtNi-W alloy nanocrystals loaded on carbon surface with atomically dispersed W sites by a two-step straightforward method.Single-atomic W can be found on the carbon surface,which can form protonic acid sites and establish an extended proton transport network at the catalyst surface.When implemented in membrane electrode assembly as cathode at ultra-low loading of 0.05 mgPt cm^(−2),the peak power density of the cell is enhanced by 64.4%compared to that with the commercial Pt/C catalyst.The theoretical calculation suggests that the single-atomic W possesses a favorable energetics toward the formation of*OOH whereby the intermediates can be efficiently converted and further reduced to water,revealing a interfacial cascade catalysis facilitated by the single-atomic W.This work highlights a novel functional hybrid electrocatalyst design from the atomic level that enables to solve the bottle-neck issues at device level.

高离子电导率及耐碱性聚三唑鎓盐薄膜的制备及性能

1,2,3-三唑鎓离子因不含酸性质子,耐碱稳定性良好,使得聚三唑鎓离子液体在聚电解质碱性电池离子交换膜等领域具有较好的应用潜力。文中将三炔正丁基-1,3,5-均苯三甲酸酯(TRBB)和端炔基聚乙二醇(DPPEG)与联苯二苄叠氮(BAMBP),通过1,3-偶极环加成反应及N-烷基化和阴离子交换反应,制备了具有高离子电导率及良好耐碱稳定性的新型超支化型聚三唑鎓盐薄膜(TDB-PTAIM)。TDB-PTAIM玻璃化转变温度(Tg)为70.8~143.6℃,质量损失10%的温度(Td10)为295~315℃,30℃最高电导率可达2.92×10-5 S/cm,在已报道的聚三唑鎓盐离子液体中处于较高水平;同时,TDB-PTAIM表现出较好的耐碱稳定性,在80℃浓度为1 mol/L的NaOH溶液中浸泡24 h后,仍能保持良好的力学性能,拉伸强度为25.6~57.4 MPa,下降幅度为9%~41%,离子电导率下降幅度为14%~23%。TDB-PTAIM兼具较好的力学性能、较高的离子电导率和较好的耐碱性能,有望应用于碱性电池离子交换膜领域。

Improved interfacial adhesion for stable flexible inverted perovskite solar cells

Flexible perovskite solar cells have attracted widespread attention due to their unique advantages in lightweight,high flexibility,and easy deformation,which are suitable for portable electronics.However,the inverted(p-i-n)structured devices suffer from poor stability largely due to the low adhesion at the brittle interface(the hole transport layer/perovskite).Herein,zeolitic imidazolate framework-67(ZIF-67)is applied to inverted structured cells to optimize the interface and prolong the device lifetime.As a result,the flexible devices based on ZIF-67 obtain the champion power conversion efficiency of 20.16%.Over 1000 h under continuous light irradiation,the device retains 96%and 80%of its original efficiency without and with bias,respectively.Notably,devices show mechanical endurance with over 78%efficiency retention after 10,000 cycles of consecutive bending cycles(R=6 mm).The introduction of ZIF-67 suppresses the cracking in device bending,which results in improved environmental stability and bending durability.

Impacts of Changes in Structure of Rural Land Property Rights on Agricultural Performance

In the reform process of the rural land property rights system,the incentive mechanism of the rural land property rights system has a crucial impact on the production activities of rural economic entities.Due to the different rights structures of the property rights system in different social and economic development stages,the land rights and interests enjoyed by rural economic subjects are different,and the degree of incentives for farmers is also different.This difference in incentives affects farmers investment in agricultural production factors,which in turn affects agricultural performance.This paper analyzes the incentive impacts of the structure of rural land property rights on the changes of farmers land rights and agricultural performance since the founding of the People s Republic of China,in order to further deepen the reform of the land system,protect the rights and interests of farmers,promote the modernization of agriculture and rural areas,and explore the realization form and operation mechanism of the rural collective land system in the new era.

Externallyvalidated nomogramfor predicting short-term pregnancy outcome of singleton pregnancies with fetal growth restriction(FGR)

Objective This studyaimed at developing an available predictive model of singleton pregnancies with fetal growth restriction(FGR)for accurate and individualised prognosis assessment.Methods The prediction nomogram was developed by using multivariable Cox regression with data for 301 singleton FGR pregnancies at Peking University People's Hospital.External validation was performed in 321eligible singleton FGR pregnancies at the Affiliated Hospital of Qingdao University.Results Absent umbilical arterial flow,fetal anomaly,history of abnormal pregnancy,non-cephalic presentation and historyof caesarean sectionwere independent prognostic factors foradverse perinatal outcomes in singleton FGR pregnancies in the training set.In the training cohort of the internal validation set,the nomogram estimated pregnancy prognosis of FGR singleton pregnancies based on these five variables,with a concordance index(C-index)of 0.859(95%Cl:0.81 to 0.90)for predicting termination of pregnancy(TOP),which included intrauterine fetal death and therapeutic lethal induction,with a C-index of 0.92(95%Cl:0.86 to 0.98)for predicting stillbirth,and a C-index of 0.87(95%Cl:0.83 to 0.92)for predicting therapeutic lethal induction with indications.Encouragingly,consistent results wereobserved in the external validation set,witha C-index of 0.776(95%Cl:0.71 to 0.84)for predicting TOP,which included intrauterine fetal death and therapeutic lethal induction,with a C-index of 0.773(95%Cl:0.70 to 0.84)for predicting stillbirth,and a C-index of 0.776(95%Cl:0.70 to 0.85)for predicting therapeutic lethal induction with indications.Furthermore,the calibrations of the nomograms predicting the 28th and 34th TOPfreegestation week strongly corresponded to theactual survivaloutcome.Conclusion This prediction model may help clinicians indecision-making for singleton pregnancies with FGR,especially for patients with a single abnormal umbilical arterial flow orfetal anomaly,without induced labour indications for these abnormalities.

Establishment of enzyme-linked immunosorbent assay for beef and lamb contents in cooked meat

In this study,an enzyme 1linked immunosorbent assay(ELISA)was established to detect beef and 1amb components,and its performance was tested.Double-antibody sandwich ELISA was adopted and determined a coating concentration of capture antibody 3G5 of 1:4000,a working concentration of enzyme-labeled antibody 2E7-horseradish peroxidase(HRP)of 1:1000,a sample incubation time of 60 min and a detection antibody reaction time of 60 min.The specificity,sensitivity,repeatability and stability of this assay were detemmined.The limit of detection for beef and 1amb skeleta1 muscle troponin I was 45 mg/kg,the inter-assay and intra-assay recovery rates ranged from 80.4%to 115.7%,the coefficients of variation were below 13.6%,and the cIoss reaction rates of the tissue components of chicken,duck and fish were below 13.4%.The sandwich ELISA method established in this study is stable and has high accuracy.The test results were consistent with the polymerase chain reaction(PCR)method at 50 and 100 g/kg-Therefore,this ELISA method can be used to quantitatively detect beef and 1amb components in meat products.

间乙炔基苯偶氮联苯酚醛树脂的合成及性能

通过重氮偶合反应在联苯酚醛树脂(BN)中引入乙炔基苯基,合成了新型的加成固化型间乙炔基苯偶氮联苯酚醛树脂(EPABN)。采用傅里叶变换红外光谱、聚合物称量、流变测试、差示扫描量热分析(DSC)、热重分析和吸附法等表征了EPABN的结构、溶解性能、流变性能、热性能及树脂炭化产物的致密性。溶解性能测试表明,EPABN树脂能溶于丙酮、四氢呋喃等溶剂。流变性能测试表明,EPABN树脂在120~150℃有1个低黏度加工窗口。DSC结果分析表明,EPABN可行的固化工艺为140℃/2 h+161℃/2 h+192℃/4 h+231℃/4 h+280℃/4 h。EPABN树脂的T_(d)^(5)和T_(d)^(10)分别为479.7℃和545.1℃,700℃和1000℃的残碳率分别为80.96%和77.26%。树脂炭化产物的氮吸附测试及密度测试表明,随着炭化温度升高,炭化物的致密度和炭化密度均增加。EPABN固化物具有优异的热稳定性、高残碳率及碳化物具高致密性。

Highly sensitive Fe^(3+)luminescence detection via single-ion adsorption

To achieve a lower detection limit has always been a goal of analytical chemists.Herein,we demonstrate the first picomolar level detection capability for Fe3+ion via luminescence detection technology.The results of structural analysis and theoretical calculation show that Fe3+ions are adsorbed on the central node of Eu-DBM(DBM=dibenzoylmethane)sensor in the form of single ion at ultralow concentration.Subsequently,the pathways of photo-induced charge and energy transfer of the obtained Eu-DBM@Fe^(3+)material have been changed,from the initial DBM-to-Eu^(3+)before Fe^(3+)adsorption to the ultimate DBM-to-Fe^(3+)after adsorption process,which quenches the luminescence of Eu3+ion.This work not only obtains the highly sensitive luminescence detection ability,but also innovatively proposes the single-ion adsorption mechanism,both of which have important scientific and application values for the development of more efficient detection agents in the future.

FGF21 increases the sensitivity of hepatocellular carcinoma to sorafenib under hypoxia

Background:Hepatocellular carcinoma(HCC)is a common disease in human history and one of the main causes of cancer-related death.Insufficient oxygen supply in the tumor microenvironment forces cancer cells to survive in a mild hypoxia environment.Fibroblast growth factor 21(FGF21),a member of the FGF family,has become the focus of public attention due to its outstanding achievements in diabetes and lipid lowering.However,the mechanism of FGF21 in HCC remains unclear.Objective:The aims of this study were to clarify whether or not FGF21 could increase the sensitivity of HCC to sorafenib(SORA)under hypoxia and explore the possible mechanism.Methods:In this study,by using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide cell viability test,plate clone formation test,western blot analysis,Hoechst/propidium iodide double staining experiment,flow cytometry,quantitative reverse transcription polymerase chain reaction,and subcutaneous tumor transplantation in mice,we studied the effects of recombinant human FGF21 combined with SORA on hepatoma cells in vitro and in vivo.FGF21 could enhance the phosphorylation of mothers against decapentaplegic homolog 3(Smad3)under anaerobic conditions.When combined with SORA,FGF21 could increase the sensitivity of hepatoma cells to SORA and inhibit the growth and migration of hepatoma cells.Results:FGF21 may increase the sensitivity of HCC to SORA by enhancing the phosphorylation of Smad3 through the phosphatidylinositol 3-kinase/protein kinase B pathway under hypoxia.Conclusion:Our study suggested the possibility of combination therapy for SORA and FGF21 on HCC.

Autoantibody to MOG suggests two distinct clinical subtypes of NMOSD

We characterized a unique group of patients with neuromyelitis optica spectrum disorder （NMOSD） who carded autoantibod- ies of aquaporin-4 （AQP4） and myelin-oligodendrocyte glycoprotein （MOG）. Among the 125 NMOSD patients, 10 （8.0%） were AQP4- and MOG-ab double positive, and 14 （11.2%） were MOG-ab single positive. The double-positive patients had a multiphase disease course with a high annual relapse rate （P=0.0431）, and severe residual disability （P〈0.0001）. Of the dou- ble-positive patients, 70% had MS-like brain lesions, more severe edematous, multifocal regions on spinal magnetic resonance imaging （MRI）, pronounced decreases of retinal nerve fiber layer thickness and atrophy of optic nerves. In contrast, patients with only MOG-ab had a higher ratio of monophasic disease course and mild residual disability. Spinal cord MRI illustrated multifocal cord lesions with mild edema, and brain MRIs showed more lesions around lateral ventricles. NMOSD patients carrying both autoantibodies to AQP4 and MOG existed and exhibited combined features of prototypic NMO and relaps- ing-remitting form of MS, whereas NMOSD with antibodies to MOG only exhibited an ＂intermediate＂ phenotype between NMOSD and MS. Our study suggests that antibodies against MOG might be pathogenic in NMOSD patients and that determi- nation of anti-MOG antibodies maybe instructive for management of NMOSD patients.

Heterojunction-Type Photocatalytic System Based on Inorganic Halide Perovskite CsPbBr3

of main observation and conclusion The heterojunction-type structure has shown significant merits in tuning the optical properties and carrier physics.Inspired by the excellent absorption capability of halide perovskite materials for visible light,a series of CsPbBr3/TiO2 heterojunction-type photocatalysts with various all-inorganic-perovskite/TiO2 ratios are successfully fabricated by the ligand-assisted reprecipitation(LARP)method.The heterojunction structure extends the light absorption of TiO2 with good chemical and structural stability.A Pb-O interaction at the CsPbBr3/TiO2 interface is observed by the XPS and confirmed by the TRPL showing improved interface carrier transport and stability.The heterojunction-type catalyst shows drastically enhanced photocatalytic activity towards the direct oxidation of toluene with 02 molecule,as an important reaction for organic chemical synthesis.The optimized sample shows an activity of 2356μmol·g^-1·h^-1 at 75℃,4 times of that of the naked CsPbBr3 nanocrystals,and 3 times of that of the bare TiO2.Based on the investigation with trapping agents,a reaction mechanism is hence proposed suggesting that the photo-generated hole may be involved in the rate-limiting step.This work demonstrates the potential of inorganic halide perovskite-based heterojunction structure for photocatalytic applications.

Efficient catalytic hydrogen generation by intermetallic platinum-lead nanostructures with highly tunable porous feature

The water-gas shift(WGS) reaction is an essential industrial reaction for upgrading hydrogen(H2) by removing carbon monoxide(CO), while highly efficient platinum(Pt)-based catalysts for WGS with simultaneously high activity and stability are still yet to be developed due to the poisoning issue during the reaction. Herein, we report on the porous PtPb peanut nanocrystals(porous PtPb PNCs) and porous PtPb octahedron nanocrystals(porous PtPb ONCs) with controllable ratios of Pt/Pb as extremely active and stable catalysts towards WGS reaction. It exhibits the composition-dependent activity with porous PtPb PNCs-40/ZnO being the most active for WGS to H_2, 16.9 times higher than that of the commercial Pt/C. The porous PtPb PNCs-40/ZnO also display outstanding durability with barely activity decay and negligible structure and composition changes after ten successive reaction cycles. X-ray photoelectron spectroscopy(XPS) results reveal that the suitable binding energy of Pt 4f_(7/2) and the high ratio of Pt(0)to Pt(II) in porous PtPb PNCs/ZnO and porous PtPb ONCs/ZnO are crucial for the enhanced WGS activity.The CO stripping results indicate the optimized CO adsorption strength on the Pt surface ensure the excellent WGS activity and the outstanding durability. The present work demonstrates an important advance in tuning the porous metal nanomaterials as highly efficient and durable catalysts for catalysis,energy conversion and beyond.

CRT角膜塑形镜短期内镜片参数调整原因及调整效果分析

目的:探讨Paragon角膜屈光矫治类(CRT)角膜塑形镜配戴早期镜片参数调整原因,并分析调整参数后的效果。方法:回顾性系列病例研究。从2018年4月至2021年5月在北京大学人民医院眼视光中心验配CRT角膜塑形镜的患者中,随机选取符合纳入标准的近视患者65例(90眼)的眼部参数进行分析。比较镜片调整前后的镜片参数,分析镜片参数调整的原因,进一步通过自行编写的Matlab程序,计算调整镜片参数前后的角膜塑形镜形成的治疗区面积(TZA)、治疗区偏位(TZD)、治疗区内加权泽尼克离焦系数(C_(weighted defocus))等变量。根据镜片参数调整原因将患者分为视力不良组、角膜点染组和TZA大组,对总体及各组内调整前后TZA、TZD和C_(weighted defocus)的比较行配对t检验分析。结果:在纳入的90眼中,因角膜点染调整镜片参数28眼(31%),因原镜片的TZA大而调整镜片参数41眼(46%),因视力不良调整镜片参数21眼(23%)。调整镜片参数前后矢高变化量为(6.59±30.85)μm。TZA调整前(12.88±3.69)mm^(2),调整后(11.77±3.17)mm^(2),变化量为(-1.11±3.01)mm^(2);TZD调整前(0.63±0.31)mm,调整后(0.57±0.29)mm,变化量为(-0.07±0.28)mm,TZA、TZD调整前后差异均有统计学意义(t=-3.50,P=0.001;t=-2.29,P=0.024)。C_(weighted defocus)调整前(0.44±0.20)D/mm^(2),调整后(0.49±0.19)D/mm^(2),变化量为(0.03±0.20)D/mm^(2),差异无统计学意义(t=1.16,P=0.190)。结论:CRT镜片参数调整主要原因为TZA过大、角膜点染和视力不良。参数调整后镜片偏位改善,TZA缩小。

国有资产智能管理的基本框架与构建思路研究——以浙江中烟为例

2015年10月,国务院发布《关于改革和完善国有资产管理体制的若干意见》,提出要完善国有资产管理制度体系,推进资产管理提质增效。但目前我国地方国有资产管理还存在着资产管理效率低下、创新力度不够等诸多问题。本文对国有资产智能管理的基本框架和建设思路进行了系统性论述,在理论层面探讨了国有资产智能管理的定义、特点和基本框架,在应用层面以浙江中烟为例,探讨了国有资产智能管理的总体思路和国有资产智能管理平台的建设思路,以及国有资产智能管理的实施效果、不足之处与改善方向,以期丰富国有资产管理的理论和方法,为企业探索国有资产智能管理建设实践提供有益参考。

Immunogenicity and reactogenicity of heterologous immunization schedules with COVID-19 vaccines:a systematic review and network meta-analysis

Background:Data on the immunogenicity and safety of heterologous immunization schedules are inconsistent.This study aimed to evaluate the immunogenicity and safety of homologous and heterologous immunization schedules.Methods:Multiple databases with relevant studies were searched with an end date of October 31,2021,and a website including a series of Coronavirus disease 2019 studies was examined for studies before March 31,2022.Randomized controlled trials(RCTs)that compared different heterologous and homologous regimens among adults that reported immunogenicity and safety outcomes were reviewed.Primary outcomes included neutralizing antibodies against the original strain and serious adverse events(SAEs).A network meta-analysis(NMA)was conducted using a random-effects model.Results:In all,11 RCTs were included in the systematic review,and nine were ultimately included in the NMA.Among participants who received two doses of CoronaVac,another dose of mRNA or a non-replicating viral vector vaccine resulted in a significantly higher level of neutralizing antibody than a third CoronaVac 600 sino unit(SU);a dose of BNT162b2 induced the highest geometric mean ratio(GMR)of 15.24,95%confidence interval[CI]:9.53–24.39.Following one dose of BNT162b2 vaccination,a dose of mRNA-1273 generated a significantly higher level of neutralizing antibody than BNT162b2 alone(GMR=1.32;95%CI:1.06–1.64),NVX-CoV2373(GMR=1.60;95%CI:1.16–2.21),or ChAdOx1(GMR=1.80;95%CI:1.25–2.59).Following one dose of ChAdOx1,a dose of mRNA-1273 was also more effective for improving antibody levels than ChAdOx1(GMR=11.09;95%CI:8.36–14.71)or NVX-CoV2373(GMR=2.87;95%CI:1.08–3.91).No significant difference in the risk for SAEs was found in any comparisons.Conclusions:Relative to vaccination with two doses of CoronaVac,a dose of BNT162b2 as a booster substantially enhances immunogenicity reactions and has a relatively acceptable risk for SAEs relative to other vaccines.For primary vaccination,schedules including mRNA vaccines induce a greater immune response.However,the comparatively higher risk for local and systemic adverse events introduced by mRNA vaccines should be noted.Registration:PROSPERO;https://www.crd.york.ac.uk/PROSPERO/;No.CRD42021278149.