Late sowing is a critical factor that hinders achieving high-yield,good-quality wheat under rice-wheat rotation.Understanding the physiological basis and regulatory pathways that lead to high yield and sound quality l...Late sowing is a critical factor that hinders achieving high-yield,good-quality wheat under rice-wheat rotation.Understanding the physiological basis and regulatory pathways that lead to high yield and sound quality late-sown wheat is crucial for developing effective cultivation strategies.A 2-year field experiment was conducted to investigate the effects of sowing date,nitrogen(N)application rate,and planting density on wheat yield,grain quality,population characteristics,and the underlying physiological factors.The results revealed significant interactions among the sowing date,planting density,and N application in regulating both yield and quality.Late sowing reduced grain yield primarily by reducing the number of spikes and kernels.However,the latter was improved by increasing N application and the planting density,thus mitigating the yield losses caused by late sowing.Moreover,the grain protein content(GPC)and wet gluten content(WGC)increased with delayed sowing dates and higher N rates but decreased with increased planting densities.For wheat yields over 9,000 or 7,500 kg ha^(-1),the latest sowing date should not be later than Nov.4 or 15,respectively.In addition,specific criteria should be met,including a maximum of 1.5 and 1.0 million stems and tillers ha^(-1),a maximum leaf area index of 6.7 and 5.5,and a dry matter accumulation(DMA)at anthesis of 14,000 and 12,000 kg ha^(-1),respectively.For high-yield,good-quality late-sown wheat,the optimal combination is a 25%increase in the N rate(300 kg N ha^(-1))and a planting density of 2.25 million(N300D225)or 3.75 million(N300D375)plants ha^(-1)for 10-or 20-day delays in sowing,respectively.These combinations result in a higher leaf net photosynthetic rate,higher activities of leaf nitrate reductase,glutamine synthetase,grain glutamic pyruvic transaminase,and a lower sugar-N ratio during post-anthesis.展开更多
The prevalence of iron deficiency anemia(IDA)remains high in infants,resulting in growth retardation,neurodevelopmental impairment,immunodeficiency and other irreversible injuries.Efficient and safe iron supplementati...The prevalence of iron deficiency anemia(IDA)remains high in infants,resulting in growth retardation,neurodevelopmental impairment,immunodeficiency and other irreversible injuries.Efficient and safe iron supplementation for infants has been the goal of recent research.This study aims to investigate the effect of encapsulated ferric pyrophosphate(FePP)on intestinal inflammation and gut microbiota in IDA suckling rats.Newborn Sprague-Dawley rats were gavaged with low and high doses of FePP and FeSO4(2 and 10 mg Fe/kg BW,respectively)during postnatal days 2-14,while the Ctrl group was gavaged with saline.Results showed that FePP supplementation was as effective as FeSO4 in promoting growth,alleviating anemia and restoring body iron levels.Both low and high doses of FePP could significantly down-regulate the expression of pro inflammatory cytokines in the colon to the level similar to that in the Ctrl group(P>0.05).However,the high dose of FeSO4 did not show a down-regulation effect.Compared with the Ctrl group,IDA caused a disturbance of gut microbiota composition in suckling rats,and FePP could restore this dysbiosis.Besides,FePP was more beneficial than FeSO4 in increasing the abundance of beneficial bacteria such as Bacteroides and Akkermansia.Spearman’s correlation analysis showed a correlation between gut microbiota and biochemical indicators such as iron status,pro-inflammatory cytokine expression,and oxidative stress level.Overall,these findings suggested that FePP could effectively improve IDA,and is more effective than FeSO4 in alleviating intestinal inflammation and regulating gut microbiota,which provides a basis for the application of new iron fortificant in infant formula.展开更多
Topological superconductor islands are thought to be the building blocks of topological quantum bits.We produced single-crystalline VSi_(x)islands with well-defined side facets and island size more than 200nm using mo...Topological superconductor islands are thought to be the building blocks of topological quantum bits.We produced single-crystalline VSi_(x)islands with well-defined side facets and island size more than 200nm using molecular beam epitaxy on Si substrate heated to 950℃throughout the growth process.By means of scanning tunneling spectroscopy,we revealed dynamical Coulomb blockade and superconductivity on isolated islands and on islands being connected by superconducting wetting layer respectively.Bi_(2)Te_(3)films were further deposited on VSi_(x)islands.Robust and homogenous proximity effect induced superconductivity was observed on various facets of the Bi_(2)Te_(3)/VSi_(x)hetero-nanostructure.Furthermore,our high-resolution spectroscopy identified Bosonic mode excitations on the topological superconductor islands.These results may establish a playground for the vortex Majorana islands.展开更多
Rare earth-Mg-Ni-based alloys with superlattice structures are new generation negative electrode materials for the nickel metal hydride batteries.Among them,the novel AB_(4)-type superlattice structure alloy is suppos...Rare earth-Mg-Ni-based alloys with superlattice structures are new generation negative electrode materials for the nickel metal hydride batteries.Among them,the novel AB_(4)-type superlattice structure alloy is supposed to have superior cycling stability and rate capability.Yet its preparation is hindered by the crucial requirement of temperature and the special composition which is close to the other superlattice structure.Here,we prepare rare earth-Mg-Ni-based alloy and study the phase transformation of alloys to make clear the formation of AB_(4)-type phase.It is found Pr_(5)Co_(19)-type phase is converted from Ce_(5)Co_(19)-type phase and shows good stability at higher temperature compared to the Ce_(5)Co_(19)-type phase in the range of 930-970℃.Afterwards,with further 5℃increasing,AB_(4)-type superlattice structure forms at a temperature of 975℃by consuming Pr_(5)Co_(19)-type phase.In contrast with A_(5)B_(19)-type alloy,AB_(4)-type alloy has superior rate capability owing to the dominant advantages of charge transfer and hydrogen diffusion.Besides,AB_(4)-type alloy shows long lifespan whose capacity retention rates are 89.2%at the 100;cycle and 82.8%at the 200;cycle,respectively.AB_(4)-type alloy delivers 1.53 wt.%hydrogen storage capacity at room temperature and exhibits higher plateau pressure than Pr_(5)Co_(19)-type alloy.The work provides novel AB_(4)-type alloy with preferable electrochemical performance as negative electrode material to inspire the development of nickel metal hydride batteries.展开更多
End stage renal disease (ESRD), an advanced stage of chronic kidney disease, has received increasing attention as a leading public health problem (Webster et al., 2017). Chronic kidney disease (CKD) and ESRD are invar...End stage renal disease (ESRD), an advanced stage of chronic kidney disease, has received increasing attention as a leading public health problem (Webster et al., 2017). Chronic kidney disease (CKD) and ESRD are invariably accompanied by chronic systemic inflammation which plays central roles in CKD progression (Cachofeiro et al., 2008) and the increased mortality due to cardiovascular disease (Landray et al., 2004).展开更多
Because of its unique pore structure,good hydrothermal stability and high specific surface area,hierarchical TS-1 zeolite(HTS-1)has become an important catalyst for the deep oxidative desulfurization of fuel oils.In t...Because of its unique pore structure,good hydrothermal stability and high specific surface area,hierarchical TS-1 zeolite(HTS-1)has become an important catalyst for the deep oxidative desulfurization of fuel oils.In this work,HTS-1 has been successfully synthesized by a hydrothermal crystallization method using the C-SiO_(2)composite as both silicon source and mesoporous template,tetrapropylammonium hydroxide as microporous template,and tetrabutylorthotitanate as titanium source.The C-SiO_(2)composite is obtained by mild carbonization of the SiO_(2)/T-40(Tween 40)xerogel,which is prepared by the two step sol-gel method.The reaction conditions for the oxidative desulfurization(ODS)of dibenzothiophene(DBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT)over HTS-1 are optimized systematically,and the recycling performances of HTS-1 are investigated in detail.After the 15th run,HTS-1 still maintains high DBT conversion(90.6%)and 4,6-DMDBT conversion(86.0%)without deactivation.The samples before and after recycle tests are characterized by XRD,FT-IR,CHN analysis,UV-Vis and SEM techniques.The results indicate that the crystal structure and morphology of regenerated HTS-1 samples are well kept,which accounts for the good structural stability and reusability of HTS-1.In addition,active intermediates for the ODS of bulky organic sulfides over HTS-1,i.e.,Ti-peroxo(Ti-OOtBu)species,are captured by the UV-Vis technique.Finally,a possible reaction mechanism for the ODS process over HTS-1 is proposed.展开更多
As the global demographic shifts toward an aging population,understanding the efficiency of protein uti-lization in older adults becomes crucial.Our study explores the intricate relationship between protein intake and...As the global demographic shifts toward an aging population,understanding the efficiency of protein uti-lization in older adults becomes crucial.Our study explores the intricate relationship between protein intake and aging,with a focus on precision nutrition for older people.Through a meta-analysis,we con-firm a decline in protein-utilization capacity in older individuals and examine the different contributions of plant and animal protein.In experiments involving mice of different ages,older mice exhibited decreases in the biological utilization of four proteins(casein,beef protein,soy protein,and gluten),par-ticularly casein.In subsequent research,casein was studied as a key protein.A decline in gastric digestion function was observed through peptidomics and the examination of pepsin levels using casein.Nevertheless,this decline did not significantly affect the overall protein digestion during the aging pro-cess.The combined application of targeted amino acid metabolomics identified abnormal absorption of amino acids as the underlying cause of decreased protein utilization during aging,particularly emphasiz-ing a reduction in branched-chain amino acids(BCAAs)in older mice.Delving deeper into the proteomics of the intestinal protein digestion and absorption pathway,a reduction of over 60%in large neutral amino acid transporter 2(LAT2)protein expression was observed in both older humans and aged mice.The reduction in LAT2 protein was found to be a key factor influencing the diminished BCAA availability.Overall,our study establishes the significance of amino acid absorption through LAT2 in protein utiliza-tion during aging and offers a new theoretical foundation for improving protein utilization in the older adults.展开更多
The dietary fiber in oats is mainly concentrated in the bran;however,the oat bran is mostly used for livestock and poultry feed and thus has a low utilization rate and low added value.In this study,insoluble dietary f...The dietary fiber in oats is mainly concentrated in the bran;however,the oat bran is mostly used for livestock and poultry feed and thus has a low utilization rate and low added value.In this study,insoluble dietary fiber(IDF)was extracted by a combination ofα-amylase and neutral protease.The optimal extraction conditions of the IDF were obtained by response surface methodology.The material-to-water ratio was 1:12.1,the concentration ofα-amylase was 1.85%,and the hydrolysis time was 39.14 min.After purifying the crude fiber with 4%sodium oxide(Na OH),70°C hot water,and anhydrous ethanol,the purity of dietary fiber exceeded 95%.X-ray diffraction analysis indicated that the IDF was predominantly amorphous.Scanning electron microscopy showed that the IDF surface exhibited a loose porous network structure.Fourier-transform infrared spectroscopy of the crude IDF showed characteristic absorption peaks at 3626,2929,1667,1538,1455,1242,and1048 cm^(-1),while the infrared spectrum of the purified IDF showed characteristic absorption peaks at 3401,2924,1744,1643,1418,and 1040 cm^(-1),which is consistent with the structure of cellulose polysaccharide.Differential scanning calorimetry analysis showed that there were three exothermic peaks at 270–310°C,320–350°C,and 440–460°C,which may represent the pyrolysis peaks of hemicellulose,cellulose,and lignin,respectively,indicating that the oat bran IDF had good thermal stability.The results indicate that the oat bran IDF can be used for the production of dietary fiber products and health-care products.展开更多
Biometric key is generated from the user’s unique biometric features,and can effectively solve the security problems in cryptography.However,the current prevailing biometric key generation techniques such as fingerpr...Biometric key is generated from the user’s unique biometric features,and can effectively solve the security problems in cryptography.However,the current prevailing biometric key generation techniques such as fingerprint recognition and facial recognition are poor in randomness and can be forged easily.According to the characteristics of Electroencephalographic(EEG)signals such as the randomness,nonlinear and non-stationary etc.,it can significantly avoid these flaws.This paper proposes a novel method to generate keys based on EEG signals with end-edgecloud collaboration computing.Using sensors to measure motor imagery EEG data,the key is generated via pre-processing,feature extraction and classification.Experiments show the total time consumption of the key generation process is about 2.45s.Our scheme is practical and feasible,which provides a research route to generate biometric keys using EEG data.展开更多
Flooding/submergence of rice fields is a severe problem in South and South-East Asia, affecting more than 20 million hectares of rice every year. Submergence creates hypoxic or anoxic condition causing poor germinatio...Flooding/submergence of rice fields is a severe problem in South and South-East Asia, affecting more than 20 million hectares of rice every year. Submergence creates hypoxic or anoxic condition causing poor germination, seedling establishment,and enormous yield loss. Standing water in the field from weeks to months also leads to significant yield losses when large part of aerial tissues is under water. For flash flooding, a rice variety FR1A3 with tolerant gene(SUB1A) was identified. SNORKEL1 and SNORKEL2 have been identified for their ability to survive deep-water flooding by rapid elongation. Submergence stress has also been reported to adversely affect cell division and damage cellular and organelle membranes. Research on antioxidative enzymes response and genes that confer tolerance to prolonged flooding is in progress. Here we review the different anoxia responsive genes and the potential involvement of antioxidative enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase, which occur in cells of rice plant exposed to submergence stress.展开更多
Introduction:Measles,mumps,and rubella remain significant global health threats despite being vaccine-preventable diseases.The World Health Organization aims to achieve regional elimination of measles and rubella by 2...Introduction:Measles,mumps,and rubella remain significant global health threats despite being vaccine-preventable diseases.The World Health Organization aims to achieve regional elimination of measles and rubella by 2030,yet substantial disparities in vaccination coverage and disease incidence persist across regions.We analyzed global vaccination and disease data to provide evidence for optimizing immunization strategies.Methods:The study analyzed World Health Organization data on measles,mumps,and rubella from 2014–2023.Our analysis included vaccine types,recommended vaccination schedules,coverage rates,supplemental immunization activities,and disease incidence.We employed descriptive epidemiological methods for data synthesis and analysis.Results:All countries implemented≥1 measlescontaining vaccine dose,with 190(97.9%)countries using a≥2-dose schedule.Global 2nd dose of measlescontaining vaccine coverage increased from 59%to 74%during the study period.High-income regions maintained>90%coverage,while the African Region reported the lowest coverage(70%for the 1st dose and 49%for the 2nd dose of measles-containing vaccine).Supplemental immunization activities helped address coverage gaps but required integration with routine immunization systems.Rubella vaccine was implemented in 90.2%of countries,while mumps vaccine adoption remained lower at 63.9%.The African Region experienced high incidence rates for both measles(551.8 per million)and rubella(21.9 per million).The COVID-19 pandemic disrupted vaccination coverage(3%–5%decline globally),with the African Region experiencing a post-pandemic U-shaped resurgence in cases.China’s transition to the measles,mumps,and rubella vaccine has reduced mumps incidence to below 100 cases per million by 2020.Conclusions:While global control of measles,mumps,and rubella has progressed,inequities in vaccination coverage and pandemic-related disruptions threaten elimination goals.Strengthening routine immunization systems is critical.Achieving the World Health Organization’s 2030 targets will require sustained investment in health systems and implementation of equity-focused innovations.展开更多
Introduction:Infants born to HBsAg-positive mothers are exposed to hepatitis B virus(HBV)during childbirth and require timely hepatitis B vaccination(HepB)and hepatitis B immunoglobulin(HBIG)to prevent vertical transm...Introduction:Infants born to HBsAg-positive mothers are exposed to hepatitis B virus(HBV)during childbirth and require timely hepatitis B vaccination(HepB)and hepatitis B immunoglobulin(HBIG)to prevent vertical transmission.Post-vaccination serological testing(PVST)determines whether HBVexposed infants are protected,infected,or need revaccination.This study evaluated PVST implementation among HBV-exposed infants and the effectiveness of the recommended strategy to prevent mother-to-child transmission(MTCT)of HBV.Methods:This observational study of infants born to HBsAg-positive mothers evaluated implementation of the MTCT prevention strategy and PVST follow-up across five provinces in China.Chi-square tests assessed timely HepB1 and HBIG administration and HepB series completion.PVST was used to evaluate MTCT prevention effectiveness.Bivariate analyses explored factors influencing infection and protection rates among HBV-exposed infants.Results:Among 7,425 infants born to HBsAgpositive mothers,94.8%received timely HepB1 and HBIG,and 99.5%completed the full HepB vaccination series.PVST was conducted in 3,243(43.7%)infants;the median interval between HepB3 and PVST was 66 days(interquartile range:47–114).26(0.8%)infants tested HBsAg-positive;3,147(97.0%)developed protective antibody levels;and 72(2.2%)were neither infected nor protected,requiring revaccination.Maternal HBeAg positivity was a significant risk factor for MTCT prevention failure[adjusted odds ratio(aOR)=12.7,95%confidence interval(CI):4.7,34.1].Conclusions:The MTCT prevention strategy was highly effective.PVST for infants born to HBsAgpositive mothers enables evaluation of MTCT prevention strategies and improvement of strategy their effectiveness.PVST utilization should be expanded to test all HBV-exposed infants to ensure their protection and to further enhance the MTCT prevention.展开更多
Human papillomavirus(HPV)vaccination administered before viral exposure(i.e.,prior to sexual debut)effectively prevents infection with vaccine-type HPV strains and associated diseases,including cervical cancer.To adva...Human papillomavirus(HPV)vaccination administered before viral exposure(i.e.,prior to sexual debut)effectively prevents infection with vaccine-type HPV strains and associated diseases,including cervical cancer.To advance HPV vaccination efforts and cervical cancer prevention,China has incorporated the bivalent HPV vaccine(types 16/18)into its National Immunization Program(NIP)as a program vaccine.This Policy Note presents comprehensive technical and implementation guidelines for HPV vaccine deployment,encompassing guidance development methodology,target population definition,routine vaccination schedules,catch-up vaccination protocols,implementation strategies,vaccine coverage and adverse event monitoring plans,and anticipated implementation challenges with proposed mitigation measures.The Vaccine Technical Working Groups of the China CDC developed relevant technical recommendations and guidelines,which were officially issued in November 2025.展开更多
Magnetic/superconducting heterostructures have attracted significant attention due to their potential to host topological superconductivity and Majorana zero modes.In this study,we report the growth of CrTe_(2)ultrath...Magnetic/superconducting heterostructures have attracted significant attention due to their potential to host topological superconductivity and Majorana zero modes.In this study,we report the growth of CrTe_(2)ultrathin films on NbSe_(2)substrates through molecular beam epitaxy.Structural characterization revealed an initial epitaxial stabilization of a compressed Cr-Te layer,with subsequent annealing inducing a periodic stress-relief reconstruction that exhibits controllable nanoscale periodicity.Scanning tunneling spectroscopy measurements unveiled edge-localized magnetic moments.This system provides a novel platform for constructing one-dimensional magnetic chains through strain-modulated self-assembly,while simultaneously offering an atomically precise interface between magnetic and superconducting orders.Our findings advance the prospects for designing the heterostructures in topological quantum devices.展开更多
Background:Statistical data on the burden and relevant risk factors of lung cancer are valuable for policy-making.This study aimed to compare the mortality of lung cancer attributable to smoking stratified by sex and ...Background:Statistical data on the burden and relevant risk factors of lung cancer are valuable for policy-making.This study aimed to compare the mortality of lung cancer attributable to smoking stratified by sex and age among adults in China and the United States(US).Methods:We extracted age-standardized mortality rates of lung cancer during 1990-2017 using the comparative risk assessment framework of the 2017 Global Burden of Disease study.We performed an age-period-cohort analysis to estimate time trend of lung cancer mortality attributable to smoking.Results:During 1990-2017,the age-standardized mortality rate of lung cancer was increasing in China but decreasing in the US for both sexes.The mortality attributable to smoking in China showed a generally increasing trend,while a continuous decrease was observed in the US.The age-period-cohort analysis showed a similar trend of age effect among adults between China and the US:the mortality substantially increased from the 30-34 to 80-84 age group and subsequently decreased in the 90-94 age group.However,the period effect rapidly increased in Chinese adults during 1990-2017,while it tended to be stable in the US although it was still slightly increasing in women.The cohort effect generally peaked in the earlier cohort born in 1902-1906 in the two countries.Conclusions:During 1990-2017,the lung cancer mortality attributable to smoking and the period effect are generally increasing in Chinese adults;the mortality attributable to smoking is decreasing in the US adults,but the period effect tends to be stable.The rapid aging and prevalence of smoking may intensify the increasing mortality of lung cancer in China.展开更多
Lithium oxygen battery has the highest theoretical capacity among the rechargeable batteries and it can reform energy storage technology if it comes to commercialization. However,many critical challenges,mainly embody...Lithium oxygen battery has the highest theoretical capacity among the rechargeable batteries and it can reform energy storage technology if it comes to commercialization. However,many critical challenges,mainly embody as low charge/discharge round-trip efficiency and poor cycling stability,impede the development of Li-O_2 batteries. The electrolyte decomposition,lithium metal anode corrosion and sluggish oxygen reaction kinetics at cathode are all responsible for poor electrochemical performances.Particularly,the catalytic cathode of Li-O_2 batteries,playing a crucial role to reduce the oxygen during discharging and to decompose discharge products during charging,is regarded as a breakthrough point that has been comprehensive investigated. In this review,the progress and issues of electrolyte,anode and cathode,especially the catalysts used at cathode,are systematically summarized and discussed.Then the perspectives toward the developments of a long life Li-O_2 battery are also presented at last.展开更多
Summary What is already known about this topic?Vaccine effectiveness(VE)is positively correlated with the number of administered co-purified diphtheria,tetanus,and acellular pertussis vaccine(DTaP)doses.A matched case...Summary What is already known about this topic?Vaccine effectiveness(VE)is positively correlated with the number of administered co-purified diphtheria,tetanus,and acellular pertussis vaccine(DTaP)doses.A matched case-control study conducted in Zhongshan City revealed that the co-purified DTaP VE against pertussis-related illnesses in children aged 4–11 months was 42%for one dose,88%for two doses,and 95%for three doses,respectively.What is added by this report?The results of this study contribute to the current body of research.We found that the VE of co-purified DTaP against pertussis-related illness and hospitalization increased substantially,ranging from 24%–26%after one dose to 86%–87%after four doses.展开更多
Introduction:In the early stages of the coronavirus disease 2019(COVID-19)epidemic in China,the highest level of public health emergency response(Level 1 Response)was launched in all province-level administrative divi...Introduction:In the early stages of the coronavirus disease 2019(COVID-19)epidemic in China,the highest level of public health emergency response(Level 1 Response)was launched in all province-level administrative divisions(PLADs)across the country.Provision of vaccination services was selectively suspended due to the physical distancing and gathering restrictions required of Level 1 Response.The purpose of this paper is to evaluate the impact of COVID-19 on vaccination services and the effectiveness of selective vaccination service suspension and catch-up vaccinations in China.Methods:Vaccine doses administered,routine vaccination coverage levels,catch-up vaccine doses administered,and coverage levels after the catch-up campaign were determined from individual vaccination records in sampled clinics,standard routine immunization administrative coverage reports,and catch-up vaccination activity reports submitted by PLADs between October 2019 and October 2020.Results:National Immunization Program(NIP)and non-NIP vaccine doses administered in sampled clinics decreased by 80% and 90%,respectively,compared with doses administered before the COVID-19 pandemic.Coverage with the birth dose of hepatitis B vaccine(HepB1)and the Bacillus Calmette-Guérin vaccine(BCG)—two vaccinations recommended to continue throughout the epidemic due to their timecritical nature—were maintained at over 85%,while coverage of other NIP vaccines decreased to below 60%by February 2020.Catch-up vaccination coverage of the 29 PLADs,excluding Xinjiang and Xizang(Tibet),began in April 2020 and exceeded 90%;Hubei catch-up coverage was 95% by October 2020.Conclusions and Implications for Public Health Practice:The COVID-19 pandemic had a great impact on China’s vaccination services.During the epidemic and time of local transmission of the coronavirus,HepB1,BCG,rabies vaccine for postexposure prophylaxis,and tetanus antitoxin(TAT)for wound prophylaxis were maintained at high levels.Of the 69 million vaccine doses postponed during the time of local transmission of the coronavirus,94% were administered in the catch-up campaign.China’s pandemic immunization practices may provide evidence for other countries’immunization programs.展开更多
Two-dimensional(2D)Cr_((1+δ))Te_(2)materials exhibit strong magnetic ordering and high Curie temperatures,making them attractive for various applications.It is crucial to achieve controllable synthesis for their succ...Two-dimensional(2D)Cr_((1+δ))Te_(2)materials exhibit strong magnetic ordering and high Curie temperatures,making them attractive for various applications.It is crucial to achieve controllable synthesis for their successful integration into device technologies.In this study,we present the synthesis of phase-controllable 2D Cr_((1+δ))Te_(2)films on the Si(111)substrate via molecular beam epitaxy.The composition and phase transition of the as-grown Cr_((1+δ))Te_(2)films are characterized by using in-situ reflection high-energy electron diffraction,scanning tunneling microscopy,ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and theoretical calculations.At low growth temperatures,by carefully adjusting the film thickness from 2 to more than 3 layers,we achieve precise control over the phase of Cr_((1+δ))Te_(2),fromCrTe_(2)to Cr intercalated Cr_(2)Te_(3).At a relatively elevated growth temperature,it is demonstrated that the Cr_((1+δ))Te_(2)phase is independent of the film thickness,only Cr_(2)Te_(3)forms and its growth mode is thickness-dependent.These phase transitions at low growth temperatures and growth mode changes at elevated growth temperatures are attributed to interfacial effects and the phase stability of Cr_((1+δ))Te_(2)compounds.Additionally,we utilize scanning tunneling spectroscopy and computations to gain insights into the electronic properties of Cr_(2)Te_(3).The magnetic measurements reveal that the 30-nm Cr_(2)Te_(3)film exhibits ferromagnetic behavior with a Curie temperature of about 180 K.Our work offers a robust method for the controllable growth of high-quality 2D Cr_((1+δ))Te_(2)films on Si substrates,providing an ideal platform for investigating their intrinsic properties and advancing the development of 2D magnet-based spintronics devices.展开更多
基金supported by the National Natural Science Foundation of China(32272215)the Key R&D Program of Jiangsu Province,China(BE2021361-1)the Collaborative Innovation Center for Modern Crop Production by Province and Ministry(CIC-MCP),Nanjing Agricultural University,China。
文摘Late sowing is a critical factor that hinders achieving high-yield,good-quality wheat under rice-wheat rotation.Understanding the physiological basis and regulatory pathways that lead to high yield and sound quality late-sown wheat is crucial for developing effective cultivation strategies.A 2-year field experiment was conducted to investigate the effects of sowing date,nitrogen(N)application rate,and planting density on wheat yield,grain quality,population characteristics,and the underlying physiological factors.The results revealed significant interactions among the sowing date,planting density,and N application in regulating both yield and quality.Late sowing reduced grain yield primarily by reducing the number of spikes and kernels.However,the latter was improved by increasing N application and the planting density,thus mitigating the yield losses caused by late sowing.Moreover,the grain protein content(GPC)and wet gluten content(WGC)increased with delayed sowing dates and higher N rates but decreased with increased planting densities.For wheat yields over 9,000 or 7,500 kg ha^(-1),the latest sowing date should not be later than Nov.4 or 15,respectively.In addition,specific criteria should be met,including a maximum of 1.5 and 1.0 million stems and tillers ha^(-1),a maximum leaf area index of 6.7 and 5.5,and a dry matter accumulation(DMA)at anthesis of 14,000 and 12,000 kg ha^(-1),respectively.For high-yield,good-quality late-sown wheat,the optimal combination is a 25%increase in the N rate(300 kg N ha^(-1))and a planting density of 2.25 million(N300D225)or 3.75 million(N300D375)plants ha^(-1)for 10-or 20-day delays in sowing,respectively.These combinations result in a higher leaf net photosynthetic rate,higher activities of leaf nitrate reductase,glutamine synthetase,grain glutamic pyruvic transaminase,and a lower sugar-N ratio during post-anthesis.
基金funded by the National Natural Science Foundation of China(32001676)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(CAST)(2022QNRC001).
文摘The prevalence of iron deficiency anemia(IDA)remains high in infants,resulting in growth retardation,neurodevelopmental impairment,immunodeficiency and other irreversible injuries.Efficient and safe iron supplementation for infants has been the goal of recent research.This study aims to investigate the effect of encapsulated ferric pyrophosphate(FePP)on intestinal inflammation and gut microbiota in IDA suckling rats.Newborn Sprague-Dawley rats were gavaged with low and high doses of FePP and FeSO4(2 and 10 mg Fe/kg BW,respectively)during postnatal days 2-14,while the Ctrl group was gavaged with saline.Results showed that FePP supplementation was as effective as FeSO4 in promoting growth,alleviating anemia and restoring body iron levels.Both low and high doses of FePP could significantly down-regulate the expression of pro inflammatory cytokines in the colon to the level similar to that in the Ctrl group(P>0.05).However,the high dose of FeSO4 did not show a down-regulation effect.Compared with the Ctrl group,IDA caused a disturbance of gut microbiota composition in suckling rats,and FePP could restore this dysbiosis.Besides,FePP was more beneficial than FeSO4 in increasing the abundance of beneficial bacteria such as Bacteroides and Akkermansia.Spearman’s correlation analysis showed a correlation between gut microbiota and biochemical indicators such as iron status,pro-inflammatory cytokine expression,and oxidative stress level.Overall,these findings suggested that FePP could effectively improve IDA,and is more effective than FeSO4 in alleviating intestinal inflammation and regulating gut microbiota,which provides a basis for the application of new iron fortificant in infant formula.
基金supported by the National Natural Science Foundation of China(Grant Nos.92365302,92065201,12488101,22325203,92265105,12074247,12174252,and 52102336)the Ministry of Science and Technology of China(Grant Nos.2019YFA0308600 and 2020YFA0309000)+1 种基金the Science and Technology Commission of Shanghai Municipality(Grant Nos.2019SHZDZX01,19JC1412701,20QA1405100,24LZ1401000,and LZPY2024-04)the financial support from Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302500)。
文摘Topological superconductor islands are thought to be the building blocks of topological quantum bits.We produced single-crystalline VSi_(x)islands with well-defined side facets and island size more than 200nm using molecular beam epitaxy on Si substrate heated to 950℃throughout the growth process.By means of scanning tunneling spectroscopy,we revealed dynamical Coulomb blockade and superconductivity on isolated islands and on islands being connected by superconducting wetting layer respectively.Bi_(2)Te_(3)films were further deposited on VSi_(x)islands.Robust and homogenous proximity effect induced superconductivity was observed on various facets of the Bi_(2)Te_(3)/VSi_(x)hetero-nanostructure.Furthermore,our high-resolution spectroscopy identified Bosonic mode excitations on the topological superconductor islands.These results may establish a playground for the vortex Majorana islands.
基金financially supported by the Natural Science Foundation of Hebei Province(Nos.E2019203414,E2020203081 and E2019203161)the National Natural Science Foundation of China(Nos.51701175 and 51971197)+1 种基金the Innovation Fund for the Graduate Students of Hebei Province(No.CXZZBS2020062)the Doctoral Fund of Yanshan University(No.BL19031)
文摘Rare earth-Mg-Ni-based alloys with superlattice structures are new generation negative electrode materials for the nickel metal hydride batteries.Among them,the novel AB_(4)-type superlattice structure alloy is supposed to have superior cycling stability and rate capability.Yet its preparation is hindered by the crucial requirement of temperature and the special composition which is close to the other superlattice structure.Here,we prepare rare earth-Mg-Ni-based alloy and study the phase transformation of alloys to make clear the formation of AB_(4)-type phase.It is found Pr_(5)Co_(19)-type phase is converted from Ce_(5)Co_(19)-type phase and shows good stability at higher temperature compared to the Ce_(5)Co_(19)-type phase in the range of 930-970℃.Afterwards,with further 5℃increasing,AB_(4)-type superlattice structure forms at a temperature of 975℃by consuming Pr_(5)Co_(19)-type phase.In contrast with A_(5)B_(19)-type alloy,AB_(4)-type alloy has superior rate capability owing to the dominant advantages of charge transfer and hydrogen diffusion.Besides,AB_(4)-type alloy shows long lifespan whose capacity retention rates are 89.2%at the 100;cycle and 82.8%at the 200;cycle,respectively.AB_(4)-type alloy delivers 1.53 wt.%hydrogen storage capacity at room temperature and exhibits higher plateau pressure than Pr_(5)Co_(19)-type alloy.The work provides novel AB_(4)-type alloy with preferable electrochemical performance as negative electrode material to inspire the development of nickel metal hydride batteries.
基金financially supported by the Beijing Science and Technology Project (Z181100009318005)the 111 Project from the Education Ministry of China (No.B18053)
文摘End stage renal disease (ESRD), an advanced stage of chronic kidney disease, has received increasing attention as a leading public health problem (Webster et al., 2017). Chronic kidney disease (CKD) and ESRD are invariably accompanied by chronic systemic inflammation which plays central roles in CKD progression (Cachofeiro et al., 2008) and the increased mortality due to cardiovascular disease (Landray et al., 2004).
基金This research was funded by the National Natural Science Foundation of China(21303008)Natural Science Foundation of Hubei Province of China(2012FFB00103).
文摘Because of its unique pore structure,good hydrothermal stability and high specific surface area,hierarchical TS-1 zeolite(HTS-1)has become an important catalyst for the deep oxidative desulfurization of fuel oils.In this work,HTS-1 has been successfully synthesized by a hydrothermal crystallization method using the C-SiO_(2)composite as both silicon source and mesoporous template,tetrapropylammonium hydroxide as microporous template,and tetrabutylorthotitanate as titanium source.The C-SiO_(2)composite is obtained by mild carbonization of the SiO_(2)/T-40(Tween 40)xerogel,which is prepared by the two step sol-gel method.The reaction conditions for the oxidative desulfurization(ODS)of dibenzothiophene(DBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT)over HTS-1 are optimized systematically,and the recycling performances of HTS-1 are investigated in detail.After the 15th run,HTS-1 still maintains high DBT conversion(90.6%)and 4,6-DMDBT conversion(86.0%)without deactivation.The samples before and after recycle tests are characterized by XRD,FT-IR,CHN analysis,UV-Vis and SEM techniques.The results indicate that the crystal structure and morphology of regenerated HTS-1 samples are well kept,which accounts for the good structural stability and reusability of HTS-1.In addition,active intermediates for the ODS of bulky organic sulfides over HTS-1,i.e.,Ti-peroxo(Ti-OOtBu)species,are captured by the UV-Vis technique.Finally,a possible reaction mechanism for the ODS process over HTS-1 is proposed.
基金funded by the National Key Research and Development Program of China(2023YFF1104502)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2022QNRC001).
文摘As the global demographic shifts toward an aging population,understanding the efficiency of protein uti-lization in older adults becomes crucial.Our study explores the intricate relationship between protein intake and aging,with a focus on precision nutrition for older people.Through a meta-analysis,we con-firm a decline in protein-utilization capacity in older individuals and examine the different contributions of plant and animal protein.In experiments involving mice of different ages,older mice exhibited decreases in the biological utilization of four proteins(casein,beef protein,soy protein,and gluten),par-ticularly casein.In subsequent research,casein was studied as a key protein.A decline in gastric digestion function was observed through peptidomics and the examination of pepsin levels using casein.Nevertheless,this decline did not significantly affect the overall protein digestion during the aging pro-cess.The combined application of targeted amino acid metabolomics identified abnormal absorption of amino acids as the underlying cause of decreased protein utilization during aging,particularly emphasiz-ing a reduction in branched-chain amino acids(BCAAs)in older mice.Delving deeper into the proteomics of the intestinal protein digestion and absorption pathway,a reduction of over 60%in large neutral amino acid transporter 2(LAT2)protein expression was observed in both older humans and aged mice.The reduction in LAT2 protein was found to be a key factor influencing the diminished BCAA availability.Overall,our study establishes the significance of amino acid absorption through LAT2 in protein utiliza-tion during aging and offers a new theoretical foundation for improving protein utilization in the older adults.
基金supported by the Natural Science Foundation of Tianjin,China(No.17JCYBJC20400)。
文摘The dietary fiber in oats is mainly concentrated in the bran;however,the oat bran is mostly used for livestock and poultry feed and thus has a low utilization rate and low added value.In this study,insoluble dietary fiber(IDF)was extracted by a combination ofα-amylase and neutral protease.The optimal extraction conditions of the IDF were obtained by response surface methodology.The material-to-water ratio was 1:12.1,the concentration ofα-amylase was 1.85%,and the hydrolysis time was 39.14 min.After purifying the crude fiber with 4%sodium oxide(Na OH),70°C hot water,and anhydrous ethanol,the purity of dietary fiber exceeded 95%.X-ray diffraction analysis indicated that the IDF was predominantly amorphous.Scanning electron microscopy showed that the IDF surface exhibited a loose porous network structure.Fourier-transform infrared spectroscopy of the crude IDF showed characteristic absorption peaks at 3626,2929,1667,1538,1455,1242,and1048 cm^(-1),while the infrared spectrum of the purified IDF showed characteristic absorption peaks at 3401,2924,1744,1643,1418,and 1040 cm^(-1),which is consistent with the structure of cellulose polysaccharide.Differential scanning calorimetry analysis showed that there were three exothermic peaks at 270–310°C,320–350°C,and 440–460°C,which may represent the pyrolysis peaks of hemicellulose,cellulose,and lignin,respectively,indicating that the oat bran IDF had good thermal stability.The results indicate that the oat bran IDF can be used for the production of dietary fiber products and health-care products.
基金supported by the National Natural Science Founds of China (62072368, U20B2050)Key Research and Development Program of Shaanxi Province (2020GY-039, 2021ZDLGY05-09, 2022GY040)
文摘Biometric key is generated from the user’s unique biometric features,and can effectively solve the security problems in cryptography.However,the current prevailing biometric key generation techniques such as fingerprint recognition and facial recognition are poor in randomness and can be forged easily.According to the characteristics of Electroencephalographic(EEG)signals such as the randomness,nonlinear and non-stationary etc.,it can significantly avoid these flaws.This paper proposes a novel method to generate keys based on EEG signals with end-edgecloud collaboration computing.Using sensors to measure motor imagery EEG data,the key is generated via pre-processing,feature extraction and classification.Experiments show the total time consumption of the key generation process is about 2.45s.Our scheme is practical and feasible,which provides a research route to generate biometric keys using EEG data.
文摘Flooding/submergence of rice fields is a severe problem in South and South-East Asia, affecting more than 20 million hectares of rice every year. Submergence creates hypoxic or anoxic condition causing poor germination, seedling establishment,and enormous yield loss. Standing water in the field from weeks to months also leads to significant yield losses when large part of aerial tissues is under water. For flash flooding, a rice variety FR1A3 with tolerant gene(SUB1A) was identified. SNORKEL1 and SNORKEL2 have been identified for their ability to survive deep-water flooding by rapid elongation. Submergence stress has also been reported to adversely affect cell division and damage cellular and organelle membranes. Research on antioxidative enzymes response and genes that confer tolerance to prolonged flooding is in progress. Here we review the different anoxia responsive genes and the potential involvement of antioxidative enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase, which occur in cells of rice plant exposed to submergence stress.
基金Supported by the operation of the public health emergency response mechanism of the Chinese Center for Disease Control and Prevention(102393220020010000017-251705)the World Health Organization development for manual of measles elimination.
文摘Introduction:Measles,mumps,and rubella remain significant global health threats despite being vaccine-preventable diseases.The World Health Organization aims to achieve regional elimination of measles and rubella by 2030,yet substantial disparities in vaccination coverage and disease incidence persist across regions.We analyzed global vaccination and disease data to provide evidence for optimizing immunization strategies.Methods:The study analyzed World Health Organization data on measles,mumps,and rubella from 2014–2023.Our analysis included vaccine types,recommended vaccination schedules,coverage rates,supplemental immunization activities,and disease incidence.We employed descriptive epidemiological methods for data synthesis and analysis.Results:All countries implemented≥1 measlescontaining vaccine dose,with 190(97.9%)countries using a≥2-dose schedule.Global 2nd dose of measlescontaining vaccine coverage increased from 59%to 74%during the study period.High-income regions maintained>90%coverage,while the African Region reported the lowest coverage(70%for the 1st dose and 49%for the 2nd dose of measles-containing vaccine).Supplemental immunization activities helped address coverage gaps but required integration with routine immunization systems.Rubella vaccine was implemented in 90.2%of countries,while mumps vaccine adoption remained lower at 63.9%.The African Region experienced high incidence rates for both measles(551.8 per million)and rubella(21.9 per million).The COVID-19 pandemic disrupted vaccination coverage(3%–5%decline globally),with the African Region experiencing a post-pandemic U-shaped resurgence in cases.China’s transition to the measles,mumps,and rubella vaccine has reduced mumps incidence to below 100 cases per million by 2020.Conclusions:While global control of measles,mumps,and rubella has progressed,inequities in vaccination coverage and pandemic-related disruptions threaten elimination goals.Strengthening routine immunization systems is critical.Achieving the World Health Organization’s 2030 targets will require sustained investment in health systems and implementation of equity-focused innovations.
基金funded by the Major Science and Technology Special Project of China’s 13th 5-Year Plan(grant no.2017ZX10105015).
文摘Introduction:Infants born to HBsAg-positive mothers are exposed to hepatitis B virus(HBV)during childbirth and require timely hepatitis B vaccination(HepB)and hepatitis B immunoglobulin(HBIG)to prevent vertical transmission.Post-vaccination serological testing(PVST)determines whether HBVexposed infants are protected,infected,or need revaccination.This study evaluated PVST implementation among HBV-exposed infants and the effectiveness of the recommended strategy to prevent mother-to-child transmission(MTCT)of HBV.Methods:This observational study of infants born to HBsAg-positive mothers evaluated implementation of the MTCT prevention strategy and PVST follow-up across five provinces in China.Chi-square tests assessed timely HepB1 and HBIG administration and HepB series completion.PVST was used to evaluate MTCT prevention effectiveness.Bivariate analyses explored factors influencing infection and protection rates among HBV-exposed infants.Results:Among 7,425 infants born to HBsAgpositive mothers,94.8%received timely HepB1 and HBIG,and 99.5%completed the full HepB vaccination series.PVST was conducted in 3,243(43.7%)infants;the median interval between HepB3 and PVST was 66 days(interquartile range:47–114).26(0.8%)infants tested HBsAg-positive;3,147(97.0%)developed protective antibody levels;and 72(2.2%)were neither infected nor protected,requiring revaccination.Maternal HBeAg positivity was a significant risk factor for MTCT prevention failure[adjusted odds ratio(aOR)=12.7,95%confidence interval(CI):4.7,34.1].Conclusions:The MTCT prevention strategy was highly effective.PVST for infants born to HBsAgpositive mothers enables evaluation of MTCT prevention strategies and improvement of strategy their effectiveness.PVST utilization should be expanded to test all HBV-exposed infants to ensure their protection and to further enhance the MTCT prevention.
文摘Human papillomavirus(HPV)vaccination administered before viral exposure(i.e.,prior to sexual debut)effectively prevents infection with vaccine-type HPV strains and associated diseases,including cervical cancer.To advance HPV vaccination efforts and cervical cancer prevention,China has incorporated the bivalent HPV vaccine(types 16/18)into its National Immunization Program(NIP)as a program vaccine.This Policy Note presents comprehensive technical and implementation guidelines for HPV vaccine deployment,encompassing guidance development methodology,target population definition,routine vaccination schedules,catch-up vaccination protocols,implementation strategies,vaccine coverage and adverse event monitoring plans,and anticipated implementation challenges with proposed mitigation measures.The Vaccine Technical Working Groups of the China CDC developed relevant technical recommendations and guidelines,which were officially issued in November 2025.
基金NSFC(Grants No.12488101,92365302,12474156,22325203,52102336,12474121)the Ministry of Science and Technology of China(Grants No.2020YFA0309000,2024YFA1410100)+2 种基金the Science and Technology Commission of Shanghai Municipality(Grants No.2019SHZDZX01,20QA1405100,24LZ1401000)Cultivation Project of Shanghai Research Center for Quantum Sciences(Grant No.LZPY2024-04)innovation program for Quantum Science and Technology(Grant No.2021ZD0302500)for financial support.
文摘Magnetic/superconducting heterostructures have attracted significant attention due to their potential to host topological superconductivity and Majorana zero modes.In this study,we report the growth of CrTe_(2)ultrathin films on NbSe_(2)substrates through molecular beam epitaxy.Structural characterization revealed an initial epitaxial stabilization of a compressed Cr-Te layer,with subsequent annealing inducing a periodic stress-relief reconstruction that exhibits controllable nanoscale periodicity.Scanning tunneling spectroscopy measurements unveiled edge-localized magnetic moments.This system provides a novel platform for constructing one-dimensional magnetic chains through strain-modulated self-assembly,while simultaneously offering an atomically precise interface between magnetic and superconducting orders.Our findings advance the prospects for designing the heterostructures in topological quantum devices.
基金This work was funded by the National Key Research and Development Program of China[grant numbers 2018YFC1315302,2017YFC1200502]the National Natural Science Foundation of China[grant number 81773552].
文摘Background:Statistical data on the burden and relevant risk factors of lung cancer are valuable for policy-making.This study aimed to compare the mortality of lung cancer attributable to smoking stratified by sex and age among adults in China and the United States(US).Methods:We extracted age-standardized mortality rates of lung cancer during 1990-2017 using the comparative risk assessment framework of the 2017 Global Burden of Disease study.We performed an age-period-cohort analysis to estimate time trend of lung cancer mortality attributable to smoking.Results:During 1990-2017,the age-standardized mortality rate of lung cancer was increasing in China but decreasing in the US for both sexes.The mortality attributable to smoking in China showed a generally increasing trend,while a continuous decrease was observed in the US.The age-period-cohort analysis showed a similar trend of age effect among adults between China and the US:the mortality substantially increased from the 30-34 to 80-84 age group and subsequently decreased in the 90-94 age group.However,the period effect rapidly increased in Chinese adults during 1990-2017,while it tended to be stable in the US although it was still slightly increasing in women.The cohort effect generally peaked in the earlier cohort born in 1902-1906 in the two countries.Conclusions:During 1990-2017,the lung cancer mortality attributable to smoking and the period effect are generally increasing in Chinese adults;the mortality attributable to smoking is decreasing in the US adults,but the period effect tends to be stable.The rapid aging and prevalence of smoking may intensify the increasing mortality of lung cancer in China.
基金supported by the Australian Research Council (ARC) through the ARC Future Fellow project (FT110100800)Discovery Project (DP160104340)+3 种基金DECRA project (DE140100619)the support from the University of Technology Sydney Chancellor’s Post Doctoral Fellowshipthe financial support from Shanghai Science & Technology Committee (15520720600)the support from Program for Professor of Special Appointment in Shanghai (Eastern Scholar)
文摘Lithium oxygen battery has the highest theoretical capacity among the rechargeable batteries and it can reform energy storage technology if it comes to commercialization. However,many critical challenges,mainly embody as low charge/discharge round-trip efficiency and poor cycling stability,impede the development of Li-O_2 batteries. The electrolyte decomposition,lithium metal anode corrosion and sluggish oxygen reaction kinetics at cathode are all responsible for poor electrochemical performances.Particularly,the catalytic cathode of Li-O_2 batteries,playing a crucial role to reduce the oxygen during discharging and to decompose discharge products during charging,is regarded as a breakthrough point that has been comprehensive investigated. In this review,the progress and issues of electrolyte,anode and cathode,especially the catalysts used at cathode,are systematically summarized and discussed.Then the perspectives toward the developments of a long life Li-O_2 battery are also presented at last.
基金Supported by the Joint Foundation of Beijing Natural Science Foundation and Haidian Original Innovation(L202037)as well as the Chinese Center for Disease Control and Prevention's Operation of Public Health Emergency Response Mechanism(131031001000200001).
文摘Summary What is already known about this topic?Vaccine effectiveness(VE)is positively correlated with the number of administered co-purified diphtheria,tetanus,and acellular pertussis vaccine(DTaP)doses.A matched case-control study conducted in Zhongshan City revealed that the co-purified DTaP VE against pertussis-related illnesses in children aged 4–11 months was 42%for one dose,88%for two doses,and 95%for three doses,respectively.What is added by this report?The results of this study contribute to the current body of research.We found that the VE of co-purified DTaP against pertussis-related illness and hospitalization increased substantially,ranging from 24%–26%after one dose to 86%–87%after four doses.
基金funded by grants from the Vaccine Preventable Diseases and Immunization(VDI)of World Health Organization Office in China(No.2020/1017283-0).
文摘Introduction:In the early stages of the coronavirus disease 2019(COVID-19)epidemic in China,the highest level of public health emergency response(Level 1 Response)was launched in all province-level administrative divisions(PLADs)across the country.Provision of vaccination services was selectively suspended due to the physical distancing and gathering restrictions required of Level 1 Response.The purpose of this paper is to evaluate the impact of COVID-19 on vaccination services and the effectiveness of selective vaccination service suspension and catch-up vaccinations in China.Methods:Vaccine doses administered,routine vaccination coverage levels,catch-up vaccine doses administered,and coverage levels after the catch-up campaign were determined from individual vaccination records in sampled clinics,standard routine immunization administrative coverage reports,and catch-up vaccination activity reports submitted by PLADs between October 2019 and October 2020.Results:National Immunization Program(NIP)and non-NIP vaccine doses administered in sampled clinics decreased by 80% and 90%,respectively,compared with doses administered before the COVID-19 pandemic.Coverage with the birth dose of hepatitis B vaccine(HepB1)and the Bacillus Calmette-Guérin vaccine(BCG)—two vaccinations recommended to continue throughout the epidemic due to their timecritical nature—were maintained at over 85%,while coverage of other NIP vaccines decreased to below 60%by February 2020.Catch-up vaccination coverage of the 29 PLADs,excluding Xinjiang and Xizang(Tibet),began in April 2020 and exceeded 90%;Hubei catch-up coverage was 95% by October 2020.Conclusions and Implications for Public Health Practice:The COVID-19 pandemic had a great impact on China’s vaccination services.During the epidemic and time of local transmission of the coronavirus,HepB1,BCG,rabies vaccine for postexposure prophylaxis,and tetanus antitoxin(TAT)for wound prophylaxis were maintained at high levels.Of the 69 million vaccine doses postponed during the time of local transmission of the coronavirus,94% were administered in the catch-up campaign.China’s pandemic immunization practices may provide evidence for other countries’immunization programs.
基金funding provided by Shanghai Jiao Tong UniversityNSFC(Grants No.11790313,No.92065201,No.11874256,No.11874258,No.12074247,No.12174252 and No.11861161003)+3 种基金the Ministry of Science and Technology of China(Grants No.2019YFA0308600,2020YFA0309000)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000)the Science and Technology Commission of Shanghai Municipality(Grants No.2019SHZDZX01,No.19JC1412701,No.20QA1405100)for financial supportfinancial support from Innovation program for Quantum Science and Technology(Grant No.2021ZD0302500).
文摘Two-dimensional(2D)Cr_((1+δ))Te_(2)materials exhibit strong magnetic ordering and high Curie temperatures,making them attractive for various applications.It is crucial to achieve controllable synthesis for their successful integration into device technologies.In this study,we present the synthesis of phase-controllable 2D Cr_((1+δ))Te_(2)films on the Si(111)substrate via molecular beam epitaxy.The composition and phase transition of the as-grown Cr_((1+δ))Te_(2)films are characterized by using in-situ reflection high-energy electron diffraction,scanning tunneling microscopy,ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and theoretical calculations.At low growth temperatures,by carefully adjusting the film thickness from 2 to more than 3 layers,we achieve precise control over the phase of Cr_((1+δ))Te_(2),fromCrTe_(2)to Cr intercalated Cr_(2)Te_(3).At a relatively elevated growth temperature,it is demonstrated that the Cr_((1+δ))Te_(2)phase is independent of the film thickness,only Cr_(2)Te_(3)forms and its growth mode is thickness-dependent.These phase transitions at low growth temperatures and growth mode changes at elevated growth temperatures are attributed to interfacial effects and the phase stability of Cr_((1+δ))Te_(2)compounds.Additionally,we utilize scanning tunneling spectroscopy and computations to gain insights into the electronic properties of Cr_(2)Te_(3).The magnetic measurements reveal that the 30-nm Cr_(2)Te_(3)film exhibits ferromagnetic behavior with a Curie temperature of about 180 K.Our work offers a robust method for the controllable growth of high-quality 2D Cr_((1+δ))Te_(2)films on Si substrates,providing an ideal platform for investigating their intrinsic properties and advancing the development of 2D magnet-based spintronics devices.
