All-solid-state electrolytes are exceedingly attractive because of the outstanding inherent safety and energy density compared to liquid electrolytes.Whereas,it is still formidable to simultaneously design solid elect...All-solid-state electrolytes are exceedingly attractive because of the outstanding inherent safety and energy density compared to liquid electrolytes.Whereas,it is still formidable to simultaneously design solid electrolytes with favorable electrode/electrolyte interface compatibility and high ionic conductivity in a simple and scalable manner.Hence,the oxygen-vacancy-rich Gd-doped SnO_(2) nanotubes(GDS NTs)are innovatively prepared and applied to the electrolyte of all-solid-state lithium metal batteries for the first time.The addition of GDS NTs can validly construct long-range co ntinuous ion transport networks in the poly(ethylene oxide)(PEO)-based system and greatly improve the mechanical properties of the electrolyte.Compared to the PEO-based electrolyte,the composite electrolyte displays a higher lithium ion conductivity of 2.41×10^(-4) S cm^(-1) at 30℃,a higher lithium ion transference number up to 0.62 and a wider electrochemical window of 5 V at 50℃.In addition,the composite electrolyte manifests outstanding compatibility with high-voltage LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)cathode,LiFePO4 cathode and lithium metal anode.The assembled Li/Li symmetric battery exhibits stable Li plating/stripping cycling performance,which can cycle steadily for 1500 h at a capacity of 0.3 mA h cm^(-2).And Li/LiFePO4 battery still maintains a high capacity of 131.54 mA h g^(-1) at 0.5C after 800 cycles,which has a superior capacity retention rate of 93.2%.The obtained novel composite electrolyte has promising application prospects in the field of all-solid-state lithium metal cells.展开更多
Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are wi...Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are widely used in lithium metal solid-state batteries due to their unique properties.However,there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth.Herein,the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride(AlF_(3))nanofibers are introduced into the PEOLi TFSI electrolytes for the first time to prepare composite solid-state electrolytes.The AlF_(3)as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts.Besides,the specially threedimensional(3D)structure enlarges the effective contacting interface with the PEO polymer,which allows the lithium ions to be transported not only along the large aspect ratio of AlF3nanofibers,but also along the mullite phase in the transmembrane direction rapidly.Thereby,the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved.Benefiting from these advantages,the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58×10^(-4)S cm^(-1)at 30℃and the lithium ions transfer number of 0.53.In addition,the AlF3has strong binding energy with anions,low electronic conductivity and wide electrochemical stability window,and reduced nucleation overpotential of lithium during cycling,which is positive for lithium dendrite suppression in solid-state electrolytes.Thus,the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15,0.2,0.3 and 0.4 m A h cm^(-2).More importantly,the LiFePO_(4)(LFP)/Li battery still has 113.5 m A h g-1remaining after 400 cycles at 50℃and the Coulomb efficiency is nearly 100%during the long cycle.Overall,the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels,maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity,thus providing a novel approach to high performance solid-state electrolytes.展开更多
With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms...With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms,doping fluorine atoms in nanocarbon-based materials is considered an effective way to improve the performance of used battery.However,there is still a blank in the systematic review of the mechanism and research progress of fluorine-doped nanostructured carbon materials in various batteries.In this review,the synthetic routes of fluorinated/fluorine-doped nanocarbon-based(CF_x)materials under different fluorine sources and the function mechanism of CF_x in various batteries are reviewed in detail.Subsequently,judging from the dependence between the structure and electrochemical performance of nanocarbon sources,the progress of CF_x based on different dimensions(0D–3D)for primary battery applications is reviewed and the balance between energy density and power density is critically discussed.In addition,the roles of CF_x materials in secondary batteries and their current applications in recent years are summarized in detail to illustrate the effect of introducing F atoms.Finally,we envisage the prospect of CF_x materials and offer some insights and recommendations to facilitate the further exploration of CF_x materials for various high-performance battery applications.展开更多
Cave air CO_2 is a vital part of the cave environment. Most studies about cave air CO_2 variations are performed in caves with no streams; there are few studies to date regarding the relationship of cave air CO_2 vari...Cave air CO_2 is a vital part of the cave environment. Most studies about cave air CO_2 variations are performed in caves with no streams; there are few studies to date regarding the relationship of cave air CO_2 variations and drip water hydrochemistry in underground stream–developed caves. To study the relationship of underground stream, drip water, and cave air CO_2, monthly and daily monitoring of air CO_2 and of underground stream and drip water was performed in Xueyu Cave from 2012 to 2013.The results revealed that there was marked seasonal variation of air CO_2 and stream hydrochemistry in the cave. Daily variations of cave air CO_2, and of stream and drip water hydrochemistry, were notable during continuous monitoring.A dilution effect was observed by analyzing hydrochemical variations in underground stream and drip water after rainfall. High cave air CO_2 along with low p H and low δ^(13)C DIC in stream and drip water indicated that air CO_2 was one of the dominant factors controlling stream and drip water hydrochemistry on a daily scale. On a seasonal scale, stream flows may promote increased cave air CO_2 in summer; in turn, the higher cave air CO_2 could inhibit degassing of drip water and make calcite δ^(13)C more negative. Variation of calcite δ^(13)C(precipitated from drip water) was in reverse of monthly temperature, soil CO_2, and cave air CO_2. Therefore,calcite δ^(13)C in Xueyu Cave could be used to determine monthly changes outside the cave. However, considering the different precipitation rate of sediment in different seasons,it was difficult to use stalagmites to reconstruct environmental change on a seasonal scale.展开更多
Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and seventeen corn...Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set(n = 88) and a validation set(n = 29). The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez(J Anim Sci. 71:3389–98,1993). The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square(MPLS) regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results: The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration(RSQ_(cal)), cross-validation(R^2_(CV)), and validation(RSQ_v) were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQ_(cal), R^2_(CV), and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME(RPD_v= 2.38, < 2.50), the other three equations built from actually determined energy and calculated DE produced good prediction performance(RPD_vranging from 2.53 to 2.69, > 2.50) when applied to validation samples.Conclusion: These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values.展开更多
Paeonia ostii is an economically important oil crop,which has been widely cultivated in the middle and lower reaches of the Yangtze River in China in recent years.Although P.ostii is highly adaptable to the environmen...Paeonia ostii is an economically important oil crop,which has been widely cultivated in the middle and lower reaches of the Yangtze River in China in recent years.Although P.ostii is highly adaptable to the environment,the prolonged high summer temperature in this region severely inhibits its growth,which adversely affects seed yield and quality.In this study,P.ostii plants were subjected to 20℃/15℃(day/night)and 40℃/35℃(day/night)temperatures for 15 days.The changes in physiological and biochemical indicators of P.ostii under high-temperature stress were initially investigated.The results showed that with the deepening of leaf etiolation,chlorophyll a and chlorophyll b concentration,carotenoid concentration,Soil Plant Analysis Development(SPAD)values and leaf relative water content decreased significantly,while both relative electrical conductivity(REC)and free proline concentration showed an upward trend.Meanwhile,the continuous accumulation of reactive oxygen species(ROS)in P.ostii plants,led to an increased activity of antioxidant enzymes including superoxide dismutase(SOD),peroxidase(POD),catalase(CAT)and ascorbate peroxidase(APX).Moreover,with the extension of the high-temperature treatment,the anatomical structures of P.ostii were destroyed,resulting in a decreased photochemical efficiency of the photosystem II(PSII)reaction center and photosynthesis was inhibited.Taken together,these results provide reference values for understanding the physiological response of P.ostii to hightemperature stress and establish a foundation for further research on the relevant underlying molecular mechanisms.展开更多
Lithium-sulfur(Li-S) batteries and lithium-selenium(Li-Se) batteries,as environmental protection energy storage systems with outstanding theoretical specific capacities and high energy densities,have become the hotspo...Lithium-sulfur(Li-S) batteries and lithium-selenium(Li-Se) batteries,as environmental protection energy storage systems with outstanding theoretical specific capacities and high energy densities,have become the hotspots of current researches.Besides,elemental S(Se) raw materials are widely sourced and their production costs are both low,which make them considered one of the new generations of high energy density electrochemical energy storage systems with the most potential for development.However,poor conductivity of elemental S/Se and the notorious "shuttle effect" of lithium polysulfides(polyselenides) severely hinder the commercialization of Li-S/Se batteries.Thanks to the excellent electrical conductivity and strong absorption of lithium polysulfide(polyselenide) about electronically conducting polymer,some of the above thorny problems have been effectively alleviated.The review presents the fundamental studies and current development trends of common electronically conducting polymers in various components of Li-S/Se batteries,which involves polyaniline(PANI) polypyrrole(PPy),and polythiophene(PTh) with its derivatives,e.g.polyethoxythiophene(PEDOT) and poly(3,4-ethylene dioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS).Finally,the review not only summarizes the research directions and challenges facing the application of electronically conducting polymers,but also looks forward to the development prospects of them,which will provide a way for the practical use of electronically conducting polymers in Li-S/Se batteries with outstanding electrochemical properties in the short run.展开更多
The definition of relatively stable expressed internal reference genes is essential in both traditional blotting quantification and as a modern data quantitative strategy.Appropriate internal reference genes can accur...The definition of relatively stable expressed internal reference genes is essential in both traditional blotting quantification and as a modern data quantitative strategy.Appropriate internal reference genes can accurately standardize the expression abundance of target genes to avoid serious experimental errors.In this study,the expression profiles of ten candidate genes,ACT1,ACT2,GAPDH,eIF1,eIF2,α-TUB,β-TUB,TBP,RNA Pol II and RP II,were calculated for a suitable reference gene selection in Paeonia ostii T.Hong et J.X.Zhang leaves under various drought stress conditions.Data were processed by the four regularly used evaluation software.A comprehensive analysis revealed that RNA Pol II was the most stable gene and eIF2 was the least stable one.In addition,the geNorm program provided the optimal choice of two reference gene combination,RNA Pol II andβ-TUB,for qRT-PCR normalization in P.ostii subjected to different drought stress levels.Our research provided convenience for gene expression analysis in P.ostii under drought stress and promoted research of effective methods to alleviate P.ostii drought stress in the future.展开更多
Entering the new era,the healthy senior service cause in China has achieved great development.However,due to regional differences,there are still certain gaps between the actual demands of ageing service in China and ...Entering the new era,the healthy senior service cause in China has achieved great development.However,due to regional differences,there are still certain gaps between the actual demands of ageing service in China and the policies on senior service.Besides,there are some other problems to be solved,such as unimplemented associated systems and policies,insufficiency of social awareness and participation,ineffective supply and high vacancy of beds in nursing homes,the shortage and low quality of industry personnel.The development of the healthy endowment service industry needs further follow-up according to the actual situation.To solve the problems of insufficient supply of senior service resources,it is necessary to use social funds to encourage interested and capable social organizations and individuals to participate,and to form a system of senior services with Chinese characteristics with multi-disciplinary cooperation of government,industry,universities and institutes.展开更多
Particle streak velocimetry (PSV) has become one of the important branches of flow filed measurements. It extracts velocity information from particle trajectories captured by single frame long exposure images. Since t...Particle streak velocimetry (PSV) has become one of the important branches of flow filed measurements. It extracts velocity information from particle trajectories captured by single frame long exposure images. Since the defocus of moving particle is inevitable during a long exposure time and under a large magnification, a novel three-dimensional (3D) velocity measurement method named defocusing particle streak velocimetry (DPSV) is proposed in this paper. On the one hand, an extension from two-dimensional (2D) to 3D velocity measurement with a monocular system is carried out. The depth information of the particle, which reflects the position in the third dimension, is indicated by the defocusing degree (characteristic parameter σ) of the particle images. The variation of σ along the trajectory is recognized by surface fitting of the gray value distribution of particle images, assuming that σ varies linearly along the trajectory. On the other hand, based on the linear fitting for the straight trajectory, an arc fitting model is developed for curved trajectories which are commonly captured in turbulent flow. The relationship between σ and the particle depth position z is experimentally calibrated using a LED light and a diaphragm. Finally, the DPSV method is verified in a submerged jet flow field as well as in a microchannel flow field to obtain the 3D velocity field with single monocular system.展开更多
Introduction:Liver cancer and cirrhosis represent the most prevalent forms of end-stage liver diseases(ESLDs).Notably,in China,deaths attributed to ESLDs contribute significantly to the global mortality rate of these ...Introduction:Liver cancer and cirrhosis represent the most prevalent forms of end-stage liver diseases(ESLDs).Notably,in China,deaths attributed to ESLDs contribute significantly to the global mortality rate of these disorders.Enhanced comprehension of the mortality profile associated with ESLDs in China could provide crucial insights into intervention prioritization,which could in turn help reduce the overall global burden of these diseases.Methods:Data were obtained from China’s Disease Surveillance Points system.The presentation includes both crude and age-standardized mortality rates,stratified by sex,residential location,and region.Using Joinpoint Regression,trends in annual mortality rates were estimated from the period of 2008 to 2020 and expressed as the average annual percentage change(AAPC).Results:In 2020,the gross mortality rate of ESLD stood at 30.08 cases per 100,000 individuals.A higher age-standardized ESLD mortality rate was observed in males and rural populations in comparison to their female and urban counterparts,respectively.Noticeably,the highest mortality rates associated with liver cancer and cirrhosis were reported in South and Southwest China,respectively.A positive correlation was noticed between age-specific ESLD mortality rates and advancing age.Interestingly,an annual decrease in the ESLD mortality rate was observed from 2008 to 2020.In urban contexts,the AAPC of cirrhosis was noted to be higher than that of liver cancer.Conclusions:The mortality rate associated with ESLDs in China decreased between 2008 and 2020.Nevertheless,the death burden attributable to ESLD continues to be alarmingly high.Future initiatives should prioritize the reduction of ESLD mortality in particular populations:males,elderly individuals,and those residing in rural regions of South and Southwest China.The emphasis of future interventions should beplaced on antiviral therapy for adults diagnosed with viral hepatitis,and on the prevention of hepatitis B virus(HBV)infection across all demographics.展开更多
The emissions of SF6 have been restricted owing to 3400 years of atmospheric lifetime and high global warming potential(GWP)as an insulating gas in gas-insulated electrical equipment.In this study,HFO-1336mzz(E)and N_...The emissions of SF6 have been restricted owing to 3400 years of atmospheric lifetime and high global warming potential(GWP)as an insulating gas in gas-insulated electrical equipment.In this study,HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are proposed as SF6 substitutes for their short atmospheric lifetime,low GWP and superior insulation performance.The GWP of HFO-1336mzz(E)is only 18 and its atmospheric lifetime is days to weeks.The breakdown voltage of 25%HFO-1336mzz(E)and N_(2)/CO_(2)mixtures is about 85%that of pure SF6 under alternating current.The self-recovery ability of HFO-1336mzz(E)and CO_(2)mixtures is superior to that of HFO-1336mzz(E)and N_(2)mixtures.The decomposition characteristic of HFO-1336mzz(E)shows that a tiny amount of its gas might initiate a carbonisation reaction to form carbon after multiple breakdown tests,which is verified by observations using energy dispersive X-rays spectroscopy and scanning electron microscope.The acute toxicity test of HFO-1336mzz(E)indicates that the gas is non-toxic.The results show that HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are potential substitutes for SF6 in electrical applications.展开更多
Parkinson’s disease(PD)is a complex neurological disorder that typically worsens with age.A wide range of pathologies makes PD a very heterogeneous condition,and there are currently no reliable diagnostic tests for t...Parkinson’s disease(PD)is a complex neurological disorder that typically worsens with age.A wide range of pathologies makes PD a very heterogeneous condition,and there are currently no reliable diagnostic tests for this disease.The application of metabolomics to the study of PD has the potential to identify disease biomarkers through the systematic evaluation of metabolites.In this study,urine metabolic profiles of 215 urine samples from 104 PD patients and 111 healthy individuals were assessed based on liquid chromatography-mass spectrometry.The urine metabolic profile was first evaluated with partial leastsquares discriminant analysis,and then we integrated the metabolomic data with ensemble machine learning techniques using the voting strategy to achieve better predictive performance.A combination of 8-metabolite predictive panel performed well with an accuracy of over 90.7%.Compared to control subjects,PD patients had higher levels of 3-methoxytyramine,N-acetyl-l-tyrosine,orotic acid,uric acid,vanillic acid,and xanthine,and lower levels of 3,3-dimethylglutaric acid and imidazolelactic acid in their urine.The multi-metabolite prediction model developed in this study can serve as an initial point for future clinical studies.展开更多
LiFePO_(4),one of the mainstream cathode materials of current EV batteries,exhibits experimental diffusion coefficients(D_(c))of Li^(+)which are not only several orders of magnitude lower than those predicted by the i...LiFePO_(4),one of the mainstream cathode materials of current EV batteries,exhibits experimental diffusion coefficients(D_(c))of Li^(+)which are not only several orders of magnitude lower than those predicted by the ionic hopping barriers obtained from theoretical calculations and spectroscopic measurements,but also span several orders from 10^(-14)to 10^(-18)cm^(2)s^(-1)under different states of charge(SOC)and the charging rates(C-rates).Atomic level understanding of such sluggishness and diversity of Li^(+)transport kinetics would be of significance in improving the rate performance of LiFePO_(4)through material and operation optimization but remain challenging.Herein,we show that the high sensitivity of Li^(+)hopping barriers on the local Li–Li coordination environments(numbers and configurations)plays a key role in the ion transport kinetics.This is due a neural network-based deep potential(DP)which allows accurate and efficient calculation of hopping barriers of Li^(+)in LiFePO_(4)with various Li–Li coordination environments,with which the kinetic Monte-Carlo(KMC)method was employed to determine the D_(c)values at various C-rates and SOC across a broad spectrum.Especially,an accelerated KMC simulation strategy is proposed to obtain the D_(c)values under a wide range of SOC at low C-rates,which agree well with that obtained from the galvanostatic intermittent titration technique(GITT).The present study provides accurate descriptions of Li^(+)transport kinetics at both very high and low C-rates,which remains challenging to experiments and first-principles calculations,respectively.Finally,it is revealed that the gradient distributions of Li^(+)density along the diffusion path result in great asymmetry in the barriers of the forward and backward hopping,causing very slow diffusion of Li^(+)and the diverse variation of D_(c).展开更多
Management information system(MiS),a human-computer system that deeply integrates next-generation information technology and management services,has become the nerve center of society and organizations.With the develo...Management information system(MiS),a human-computer system that deeply integrates next-generation information technology and management services,has become the nerve center of society and organizations.With the development of next-generation information technology,Mis has gradually entered the smart period.However,research on smart managementinformation systems(SMIS)is still limited,lacking systematic summarization of its conceptual definition,evolution,research hotspots,and typical applications.Therefore,this paper defines the conceptual characteristics of SMIS,provides an overview of the evolution of SMIS,examines research focus areas using bibliometric methods,and elaborates on typical application practices of sMis in fields such as health care,elderly care,manufacturing,and transportation.Furthermore,we discuss the future development directions of SMIS in four key areas:smart interaction,smart decisionmaking,efficient resource allocation,and flexible system architecture.These discussions provide guidance and a foundation for the theoretical development and practical application of SMIS.展开更多
Nonreciprocal interlayer coupling is difcult to practically implement in bilayer non-Hermitian topological photonic systems.In this work,we identify a similarity transformation between the Hamiltonians of systems with...Nonreciprocal interlayer coupling is difcult to practically implement in bilayer non-Hermitian topological photonic systems.In this work,we identify a similarity transformation between the Hamiltonians of systems with nonreciprocal interlayer coupling and on-site gain/loss.The similarity transformation is widely applicable,and we show its application in one-and two-dimensional bilayer topological systems as examples.The bilayer non-Hermitian system with nonreciprocal interlayer coupling,whose topological number can be defned using the gauge-smoothed Wilson loop,is topologically equivalent to the bilayer system with on-site gain/loss.We also show that the topological number of bilayer non-Hermitian C6v-typed domaininduced topological interface states can be defned in the same way as in the case of the bilayer non-Hermitian Su–Schrieffer–Heeger model.Our results show the relations between two microscopic provenances of the non-Hermiticity and provide a universal and convenient scheme for constructing and studying nonreciprocal interlayer coupling in bilayer non-Hermitian topological systems.This scheme is useful for observation of non-Hermitian skin efect in three-dimensional systems.展开更多
Background:The objective of this study was to examine the clinical characteristics of individuals with ultra-high hepatitis B virus(HBV)viral load and develop a novel staging method for chronic hepatitis B(CHB)that ca...Background:The objective of this study was to examine the clinical characteristics of individuals with ultra-high hepatitis B virus(HBV)viral load and develop a novel staging method for chronic hepatitis B(CHB)that can more effectively identify patients with medium to high hepatocellular carcinoma(HCC)risk.Methods:A total of 2,118 patients with HBV DNA>1×10^(7) IU/mL who visited Peking University People’s Hospital between January 2010 and March 2023 were enrolled retrospectively.Clinical data from the first visit were obtained and analyzed.The traditional phases and new‘eALT-F’stages were compared to evaluate the risk of HCC.Results:In the overall patients,more than onethird of the patients were under 30 years old.Additionally,a small proportion of older people(>60 years)also had ultra-high HBV viral load(4.3%).9.1%and 6.7%of individuals with ultra-high HBV viral load showed FIB-4>3.25 and aMAP≥50,respectively.In the traditional stages of CHB,which are based on HBeAg and alanine aminotransferase(ALT)[the upper limit of normal(ULN)ALT level at 40 IU/L for both men and women],regardless of phase,a certain proportion of patients were at risk of developing HCC(4.1%,6.4%,25.0%,and 20.3%).However,in the new‘eALT-F’stages,which are based on HBeAg,ALT(the ULN of ALT level at 30 IU/L for men and 19 IU/L for women),and/or FIB-4 levels(>1.45),aMAP≥50 was only observed in chronic hepatitis patients with positive or negative HBeAg(6.4%and 22.1%,respectively).Conclusions:The‘eALT-F’staging method,based on HBeAg,ALT(males:the ULN of ALT was 30 IU/L,females:19 IU/L)and/or FIB-4 levels,was more effective in identifying medium to high-risk patients with HCC from patients with ultra-high HBV viral load than the traditional staging methods.展开更多
●The Ministry of Education Research Center for Online Education conducted a national survey of university administrators of learning and teaching.●The survey results showed that(a)the universities in eastern China h...●The Ministry of Education Research Center for Online Education conducted a national survey of university administrators of learning and teaching.●The survey results showed that(a)the universities in eastern China had developed and introduced more massive open online courses(MOOCs)than those in the central and western regions;(b)of the various measures for blended learning,the universities tended to focus on supporting hardware development before providing training and incentive measures to teachers;and(c)the universities had widely used hybrid learning approaches.In relation to hybrid learning,Tsinghua University explored infrastructure upgrades,teacher training,and the optimal use of the rain classroom and its clone class,and launched the global hybrid classroom and global open courses.●In the future,it will be necessary to further promote education equity in line with national policies and provide and perfect incentives to improve the quality of blended learning and expand hybrid learning while improving interaction through technology.展开更多
基金supported by the National Natural Science Foundation of China(52203066,51973157,61904123,51873152)the Tianjin Natural Science Foundation(18JCQNJC02900)+3 种基金the Science and Technology Plans of Tianjin(19PTSYJC00010)the Tianjin Research Innovation Project for Postgraduate Students(2021YJSB234)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(2018KJ196)State Key Laboratory of Membrane and Membrane Separation,Tiangong University。
文摘All-solid-state electrolytes are exceedingly attractive because of the outstanding inherent safety and energy density compared to liquid electrolytes.Whereas,it is still formidable to simultaneously design solid electrolytes with favorable electrode/electrolyte interface compatibility and high ionic conductivity in a simple and scalable manner.Hence,the oxygen-vacancy-rich Gd-doped SnO_(2) nanotubes(GDS NTs)are innovatively prepared and applied to the electrolyte of all-solid-state lithium metal batteries for the first time.The addition of GDS NTs can validly construct long-range co ntinuous ion transport networks in the poly(ethylene oxide)(PEO)-based system and greatly improve the mechanical properties of the electrolyte.Compared to the PEO-based electrolyte,the composite electrolyte displays a higher lithium ion conductivity of 2.41×10^(-4) S cm^(-1) at 30℃,a higher lithium ion transference number up to 0.62 and a wider electrochemical window of 5 V at 50℃.In addition,the composite electrolyte manifests outstanding compatibility with high-voltage LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)cathode,LiFePO4 cathode and lithium metal anode.The assembled Li/Li symmetric battery exhibits stable Li plating/stripping cycling performance,which can cycle steadily for 1500 h at a capacity of 0.3 mA h cm^(-2).And Li/LiFePO4 battery still maintains a high capacity of 131.54 mA h g^(-1) at 0.5C after 800 cycles,which has a superior capacity retention rate of 93.2%.The obtained novel composite electrolyte has promising application prospects in the field of all-solid-state lithium metal cells.
基金supported by the National Natural Science Foundation of China(51973157,61904123,52103061,52203066)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(2018KJ196)+3 种基金the project funded by China Postdoctoral Science Foundation(2021T140419)Tianjin Municipal College Student’Innovation and Entrepreneurship Training Program(202110058052)the National Innovation and Entrepreneurship Training Program for College Students(202110058017)the State Key Laboratory of Membrane and Membrane Separation,Tiangong University。
文摘Lithium metal batteries assembled with solid-state electrolyte can offer high safety and volumetric energy density compared to liquid electrolyte.The polymer solid-state electrolytes of poly(ethylene oxide)(PEO)are widely used in lithium metal solid-state batteries due to their unique properties.However,there are still some defects such as low ionic conductivity at room temperature and weak inhibition of lithium dendrite growth.Herein,the spiny inorganic nanofibers heterostructure with mullite whiskers grown on the surface of aluminum fluoride(AlF_(3))nanofibers are introduced into the PEOLi TFSI electrolytes for the first time to prepare composite solid-state electrolytes.The AlF_(3)as a strong Lewis acid can adsorb anions and promote the dissociation of Li salts.Besides,the specially threedimensional(3D)structure enlarges the effective contacting interface with the PEO polymer,which allows the lithium ions to be transported not only along the large aspect ratio of AlF3nanofibers,but also along the mullite phase in the transmembrane direction rapidly.Thereby,the transport channel of lithium ions at the spiny inorganic nanofibers-polymer interface is further improved.Benefiting from these advantages,the obtained composite solid-state electrolyte has a high ionic conductivity of 1.58×10^(-4)S cm^(-1)at 30℃and the lithium ions transfer number of 0.53.In addition,the AlF3has strong binding energy with anions,low electronic conductivity and wide electrochemical stability window,and reduced nucleation overpotential of lithium during cycling,which is positive for lithium dendrite suppression in solid-state electrolytes.Thus,the assembled symmetric Li/Li symmetric batteries exhibit stable cycling performance at different area capacities of 0.15,0.2,0.3 and 0.4 m A h cm^(-2).More importantly,the LiFePO_(4)(LFP)/Li battery still has 113.5 m A h g-1remaining after 400 cycles at 50℃and the Coulomb efficiency is nearly 100%during the long cycle.Overall,the interconnected structure of 3D spiny inorganic heterostructure nanofiber constitutes fast and uninterrupted lithium ions transport channels,maximizing the synergistic effect of interfacial transport of inorganic fillers and reducing PEO crystallinity,thus providing a novel approach to high performance solid-state electrolytes.
基金supported by the National Natural Science Foundation of China(51973157,61904123,52103061,52203066)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(2018KJ196)+3 种基金the project funded by China Postdoctoral Science Foundation(2021T140419)Tianjin Municipal College Student’Innovation and Entrepreneurship Training Program(202110058052)the National Innovation and Entrepreneurship Training Program for College Students(202110058017)the State Key Laboratory of Membrane and Membrane Separation,Tiangong University。
文摘With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms,doping fluorine atoms in nanocarbon-based materials is considered an effective way to improve the performance of used battery.However,there is still a blank in the systematic review of the mechanism and research progress of fluorine-doped nanostructured carbon materials in various batteries.In this review,the synthetic routes of fluorinated/fluorine-doped nanocarbon-based(CF_x)materials under different fluorine sources and the function mechanism of CF_x in various batteries are reviewed in detail.Subsequently,judging from the dependence between the structure and electrochemical performance of nanocarbon sources,the progress of CF_x based on different dimensions(0D–3D)for primary battery applications is reviewed and the balance between energy density and power density is critically discussed.In addition,the roles of CF_x materials in secondary batteries and their current applications in recent years are summarized in detail to illustrate the effect of introducing F atoms.Finally,we envisage the prospect of CF_x materials and offer some insights and recommendations to facilitate the further exploration of CF_x materials for various high-performance battery applications.
基金supported by the National Natural Science Foundation of China (NO.41072192)Academician Foundation of Chongqing Science & Technology Commission (CSTC,2010BC7004CSTC,2013JCYIYS20001)
文摘Cave air CO_2 is a vital part of the cave environment. Most studies about cave air CO_2 variations are performed in caves with no streams; there are few studies to date regarding the relationship of cave air CO_2 variations and drip water hydrochemistry in underground stream–developed caves. To study the relationship of underground stream, drip water, and cave air CO_2, monthly and daily monitoring of air CO_2 and of underground stream and drip water was performed in Xueyu Cave from 2012 to 2013.The results revealed that there was marked seasonal variation of air CO_2 and stream hydrochemistry in the cave. Daily variations of cave air CO_2, and of stream and drip water hydrochemistry, were notable during continuous monitoring.A dilution effect was observed by analyzing hydrochemical variations in underground stream and drip water after rainfall. High cave air CO_2 along with low p H and low δ^(13)C DIC in stream and drip water indicated that air CO_2 was one of the dominant factors controlling stream and drip water hydrochemistry on a daily scale. On a seasonal scale, stream flows may promote increased cave air CO_2 in summer; in turn, the higher cave air CO_2 could inhibit degassing of drip water and make calcite δ^(13)C more negative. Variation of calcite δ^(13)C(precipitated from drip water) was in reverse of monthly temperature, soil CO_2, and cave air CO_2. Therefore,calcite δ^(13)C in Xueyu Cave could be used to determine monthly changes outside the cave. However, considering the different precipitation rate of sediment in different seasons,it was difficult to use stalagmites to reconstruct environmental change on a seasonal scale.
基金financially supported by China Special Public Sector Fund in Agriculture(200903006)The collection of data and analysis were funded by National Key Technology Research and Development Program(2011BAD26B0404)The interpretation of data and writing of the manuscript were supported by 111 Project(B16044)
文摘Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set(n = 88) and a validation set(n = 29). The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez(J Anim Sci. 71:3389–98,1993). The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square(MPLS) regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results: The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration(RSQ_(cal)), cross-validation(R^2_(CV)), and validation(RSQ_v) were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQ_(cal), R^2_(CV), and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME(RPD_v= 2.38, < 2.50), the other three equations built from actually determined energy and calculated DE produced good prediction performance(RPD_vranging from 2.53 to 2.69, > 2.50) when applied to validation samples.Conclusion: These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values.
基金This work was supported by the National Key Research and Development Project of China[2019YFD1001502]Forestry Science and Technology Prossmotion Project of Jiangsu Province[LYKJ[2018]26],Qing Lan Project of Jiangsu Province and High-Level Talent Support Program of Yangzhou University.
文摘Paeonia ostii is an economically important oil crop,which has been widely cultivated in the middle and lower reaches of the Yangtze River in China in recent years.Although P.ostii is highly adaptable to the environment,the prolonged high summer temperature in this region severely inhibits its growth,which adversely affects seed yield and quality.In this study,P.ostii plants were subjected to 20℃/15℃(day/night)and 40℃/35℃(day/night)temperatures for 15 days.The changes in physiological and biochemical indicators of P.ostii under high-temperature stress were initially investigated.The results showed that with the deepening of leaf etiolation,chlorophyll a and chlorophyll b concentration,carotenoid concentration,Soil Plant Analysis Development(SPAD)values and leaf relative water content decreased significantly,while both relative electrical conductivity(REC)and free proline concentration showed an upward trend.Meanwhile,the continuous accumulation of reactive oxygen species(ROS)in P.ostii plants,led to an increased activity of antioxidant enzymes including superoxide dismutase(SOD),peroxidase(POD),catalase(CAT)and ascorbate peroxidase(APX).Moreover,with the extension of the high-temperature treatment,the anatomical structures of P.ostii were destroyed,resulting in a decreased photochemical efficiency of the photosystem II(PSII)reaction center and photosynthesis was inhibited.Taken together,these results provide reference values for understanding the physiological response of P.ostii to hightemperature stress and establish a foundation for further research on the relevant underlying molecular mechanisms.
基金the National Natural Science Foundation of China(51973157)the Special Grade of the Financial Support from the China Postdoctoral Science Foundation(2020T130469)+1 种基金the China Postdoctoral Science Foundation Grant(2019 M651047)the Science and Technology Plans of Tianjin(19PTSYJC00010)for their financial support。
文摘Lithium-sulfur(Li-S) batteries and lithium-selenium(Li-Se) batteries,as environmental protection energy storage systems with outstanding theoretical specific capacities and high energy densities,have become the hotspots of current researches.Besides,elemental S(Se) raw materials are widely sourced and their production costs are both low,which make them considered one of the new generations of high energy density electrochemical energy storage systems with the most potential for development.However,poor conductivity of elemental S/Se and the notorious "shuttle effect" of lithium polysulfides(polyselenides) severely hinder the commercialization of Li-S/Se batteries.Thanks to the excellent electrical conductivity and strong absorption of lithium polysulfide(polyselenide) about electronically conducting polymer,some of the above thorny problems have been effectively alleviated.The review presents the fundamental studies and current development trends of common electronically conducting polymers in various components of Li-S/Se batteries,which involves polyaniline(PANI) polypyrrole(PPy),and polythiophene(PTh) with its derivatives,e.g.polyethoxythiophene(PEDOT) and poly(3,4-ethylene dioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS).Finally,the review not only summarizes the research directions and challenges facing the application of electronically conducting polymers,but also looks forward to the development prospects of them,which will provide a way for the practical use of electronically conducting polymers in Li-S/Se batteries with outstanding electrochemical properties in the short run.
基金This work was supported by the National Key R&D Program of China(2018YFD1000405)Jiangsu Modern Agricultural Industrial Technology System(JATS[2020]436)。
文摘The definition of relatively stable expressed internal reference genes is essential in both traditional blotting quantification and as a modern data quantitative strategy.Appropriate internal reference genes can accurately standardize the expression abundance of target genes to avoid serious experimental errors.In this study,the expression profiles of ten candidate genes,ACT1,ACT2,GAPDH,eIF1,eIF2,α-TUB,β-TUB,TBP,RNA Pol II and RP II,were calculated for a suitable reference gene selection in Paeonia ostii T.Hong et J.X.Zhang leaves under various drought stress conditions.Data were processed by the four regularly used evaluation software.A comprehensive analysis revealed that RNA Pol II was the most stable gene and eIF2 was the least stable one.In addition,the geNorm program provided the optimal choice of two reference gene combination,RNA Pol II andβ-TUB,for qRT-PCR normalization in P.ostii subjected to different drought stress levels.Our research provided convenience for gene expression analysis in P.ostii under drought stress and promoted research of effective methods to alleviate P.ostii drought stress in the future.
基金the National Natural Science Foundation Project (Grant No. 71774147)-Research on multi-agent collaborative management model in elderly health service based on complex system theoryand the Ministry of Education’s Doctor Training Program for national special needs “Disease Prevention and Health Management”(Degree [2018] No. 46).
文摘Entering the new era,the healthy senior service cause in China has achieved great development.However,due to regional differences,there are still certain gaps between the actual demands of ageing service in China and the policies on senior service.Besides,there are some other problems to be solved,such as unimplemented associated systems and policies,insufficiency of social awareness and participation,ineffective supply and high vacancy of beds in nursing homes,the shortage and low quality of industry personnel.The development of the healthy endowment service industry needs further follow-up according to the actual situation.To solve the problems of insufficient supply of senior service resources,it is necessary to use social funds to encourage interested and capable social organizations and individuals to participate,and to form a system of senior services with Chinese characteristics with multi-disciplinary cooperation of government,industry,universities and institutes.
基金supported by the National Natural Science Foun-dation of China(grant numbers 51906154,51576130)NaturalScience Foundation of Shanghai(grant number 21ZR1443700).
文摘Particle streak velocimetry (PSV) has become one of the important branches of flow filed measurements. It extracts velocity information from particle trajectories captured by single frame long exposure images. Since the defocus of moving particle is inevitable during a long exposure time and under a large magnification, a novel three-dimensional (3D) velocity measurement method named defocusing particle streak velocimetry (DPSV) is proposed in this paper. On the one hand, an extension from two-dimensional (2D) to 3D velocity measurement with a monocular system is carried out. The depth information of the particle, which reflects the position in the third dimension, is indicated by the defocusing degree (characteristic parameter σ) of the particle images. The variation of σ along the trajectory is recognized by surface fitting of the gray value distribution of particle images, assuming that σ varies linearly along the trajectory. On the other hand, based on the linear fitting for the straight trajectory, an arc fitting model is developed for curved trajectories which are commonly captured in turbulent flow. The relationship between σ and the particle depth position z is experimentally calibrated using a LED light and a diaphragm. Finally, the DPSV method is verified in a submerged jet flow field as well as in a microchannel flow field to obtain the 3D velocity field with single monocular system.
基金Supported by the Beijing Natural Science Foundation[No.7232195]National Natural Science Foundation of China[No.81870406,and No.81602939]+2 种基金Capital’s Funds for Health Improvement and Research[No.2020-4-4087]Peking University Medicine Sailing Program for Young Scholars’Scientific&Technological Innovation[No.BMU2023YFJHPY025]Chinese foundation for hepatitis prevention and control-TianQing liver disease research fund subject[No.TQGB20210139]。
文摘Introduction:Liver cancer and cirrhosis represent the most prevalent forms of end-stage liver diseases(ESLDs).Notably,in China,deaths attributed to ESLDs contribute significantly to the global mortality rate of these disorders.Enhanced comprehension of the mortality profile associated with ESLDs in China could provide crucial insights into intervention prioritization,which could in turn help reduce the overall global burden of these diseases.Methods:Data were obtained from China’s Disease Surveillance Points system.The presentation includes both crude and age-standardized mortality rates,stratified by sex,residential location,and region.Using Joinpoint Regression,trends in annual mortality rates were estimated from the period of 2008 to 2020 and expressed as the average annual percentage change(AAPC).Results:In 2020,the gross mortality rate of ESLD stood at 30.08 cases per 100,000 individuals.A higher age-standardized ESLD mortality rate was observed in males and rural populations in comparison to their female and urban counterparts,respectively.Noticeably,the highest mortality rates associated with liver cancer and cirrhosis were reported in South and Southwest China,respectively.A positive correlation was noticed between age-specific ESLD mortality rates and advancing age.Interestingly,an annual decrease in the ESLD mortality rate was observed from 2008 to 2020.In urban contexts,the AAPC of cirrhosis was noted to be higher than that of liver cancer.Conclusions:The mortality rate associated with ESLDs in China decreased between 2008 and 2020.Nevertheless,the death burden attributable to ESLD continues to be alarmingly high.Future initiatives should prioritize the reduction of ESLD mortality in particular populations:males,elderly individuals,and those residing in rural regions of South and Southwest China.The emphasis of future interventions should beplaced on antiviral therapy for adults diagnosed with viral hepatitis,and on the prevention of hepatitis B virus(HBV)infection across all demographics.
基金National Key R&D Program of China,Grant/Award Numbers:2017YFB0902500,2021YFB2401400Science and Technology Project of State Grid。
文摘The emissions of SF6 have been restricted owing to 3400 years of atmospheric lifetime and high global warming potential(GWP)as an insulating gas in gas-insulated electrical equipment.In this study,HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are proposed as SF6 substitutes for their short atmospheric lifetime,low GWP and superior insulation performance.The GWP of HFO-1336mzz(E)is only 18 and its atmospheric lifetime is days to weeks.The breakdown voltage of 25%HFO-1336mzz(E)and N_(2)/CO_(2)mixtures is about 85%that of pure SF6 under alternating current.The self-recovery ability of HFO-1336mzz(E)and CO_(2)mixtures is superior to that of HFO-1336mzz(E)and N_(2)mixtures.The decomposition characteristic of HFO-1336mzz(E)shows that a tiny amount of its gas might initiate a carbonisation reaction to form carbon after multiple breakdown tests,which is verified by observations using energy dispersive X-rays spectroscopy and scanning electron microscope.The acute toxicity test of HFO-1336mzz(E)indicates that the gas is non-toxic.The results show that HFO-1336mzz(E)and N_(2)/CO_(2)mixtures are potential substitutes for SF6 in electrical applications.
基金support from the Collaborative Research Fund(No.C2011–21GF)from Guangdong Province Basic and Applied Basic Research Foundation(No.2021B1515120051).
文摘Parkinson’s disease(PD)is a complex neurological disorder that typically worsens with age.A wide range of pathologies makes PD a very heterogeneous condition,and there are currently no reliable diagnostic tests for this disease.The application of metabolomics to the study of PD has the potential to identify disease biomarkers through the systematic evaluation of metabolites.In this study,urine metabolic profiles of 215 urine samples from 104 PD patients and 111 healthy individuals were assessed based on liquid chromatography-mass spectrometry.The urine metabolic profile was first evaluated with partial leastsquares discriminant analysis,and then we integrated the metabolomic data with ensemble machine learning techniques using the voting strategy to achieve better predictive performance.A combination of 8-metabolite predictive panel performed well with an accuracy of over 90.7%.Compared to control subjects,PD patients had higher levels of 3-methoxytyramine,N-acetyl-l-tyrosine,orotic acid,uric acid,vanillic acid,and xanthine,and lower levels of 3,3-dimethylglutaric acid and imidazolelactic acid in their urine.The multi-metabolite prediction model developed in this study can serve as an initial point for future clinical studies.
基金financially supported by the National Natural Science Foundation of China(22272122,21832004 and 21673163)。
文摘LiFePO_(4),one of the mainstream cathode materials of current EV batteries,exhibits experimental diffusion coefficients(D_(c))of Li^(+)which are not only several orders of magnitude lower than those predicted by the ionic hopping barriers obtained from theoretical calculations and spectroscopic measurements,but also span several orders from 10^(-14)to 10^(-18)cm^(2)s^(-1)under different states of charge(SOC)and the charging rates(C-rates).Atomic level understanding of such sluggishness and diversity of Li^(+)transport kinetics would be of significance in improving the rate performance of LiFePO_(4)through material and operation optimization but remain challenging.Herein,we show that the high sensitivity of Li^(+)hopping barriers on the local Li–Li coordination environments(numbers and configurations)plays a key role in the ion transport kinetics.This is due a neural network-based deep potential(DP)which allows accurate and efficient calculation of hopping barriers of Li^(+)in LiFePO_(4)with various Li–Li coordination environments,with which the kinetic Monte-Carlo(KMC)method was employed to determine the D_(c)values at various C-rates and SOC across a broad spectrum.Especially,an accelerated KMC simulation strategy is proposed to obtain the D_(c)values under a wide range of SOC at low C-rates,which agree well with that obtained from the galvanostatic intermittent titration technique(GITT).The present study provides accurate descriptions of Li^(+)transport kinetics at both very high and low C-rates,which remains challenging to experiments and first-principles calculations,respectively.Finally,it is revealed that the gradient distributions of Li^(+)density along the diffusion path result in great asymmetry in the barriers of the forward and backward hopping,causing very slow diffusion of Li^(+)and the diverse variation of D_(c).
基金the National Natural Science Foundation of China(grant number:72131006,72071063,72271082)Anhui Provincial Key R&D Programme(grant number:2020i01020003).
文摘Management information system(MiS),a human-computer system that deeply integrates next-generation information technology and management services,has become the nerve center of society and organizations.With the development of next-generation information technology,Mis has gradually entered the smart period.However,research on smart managementinformation systems(SMIS)is still limited,lacking systematic summarization of its conceptual definition,evolution,research hotspots,and typical applications.Therefore,this paper defines the conceptual characteristics of SMIS,provides an overview of the evolution of SMIS,examines research focus areas using bibliometric methods,and elaborates on typical application practices of sMis in fields such as health care,elderly care,manufacturing,and transportation.Furthermore,we discuss the future development directions of SMIS in four key areas:smart interaction,smart decisionmaking,efficient resource allocation,and flexible system architecture.These discussions provide guidance and a foundation for the theoretical development and practical application of SMIS.
基金supported by the National Natural Science Foundation of China(Nos.91950204,92150302,and 62175009)Innovation Program for Quantum Science and Technology(No.2021ZD0301500)Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics(No.KF202114).
文摘Nonreciprocal interlayer coupling is difcult to practically implement in bilayer non-Hermitian topological photonic systems.In this work,we identify a similarity transformation between the Hamiltonians of systems with nonreciprocal interlayer coupling and on-site gain/loss.The similarity transformation is widely applicable,and we show its application in one-and two-dimensional bilayer topological systems as examples.The bilayer non-Hermitian system with nonreciprocal interlayer coupling,whose topological number can be defned using the gauge-smoothed Wilson loop,is topologically equivalent to the bilayer system with on-site gain/loss.We also show that the topological number of bilayer non-Hermitian C6v-typed domaininduced topological interface states can be defned in the same way as in the case of the bilayer non-Hermitian Su–Schrieffer–Heeger model.Our results show the relations between two microscopic provenances of the non-Hermiticity and provide a universal and convenient scheme for constructing and studying nonreciprocal interlayer coupling in bilayer non-Hermitian topological systems.This scheme is useful for observation of non-Hermitian skin efect in three-dimensional systems.
基金Supported by Beijing Natural Science Foundation(7232195)National Natural Science Foundation of China(82300660)+1 种基金Peking University Medicine Sailing Program for Young Scholars’Scientific&Technological Innovation(BMU2023YFJHPY025)Peking University People’s Hospital Scientific Research Development Funds(RDJP2022-60)and Qi-Min Project.
文摘Background:The objective of this study was to examine the clinical characteristics of individuals with ultra-high hepatitis B virus(HBV)viral load and develop a novel staging method for chronic hepatitis B(CHB)that can more effectively identify patients with medium to high hepatocellular carcinoma(HCC)risk.Methods:A total of 2,118 patients with HBV DNA>1×10^(7) IU/mL who visited Peking University People’s Hospital between January 2010 and March 2023 were enrolled retrospectively.Clinical data from the first visit were obtained and analyzed.The traditional phases and new‘eALT-F’stages were compared to evaluate the risk of HCC.Results:In the overall patients,more than onethird of the patients were under 30 years old.Additionally,a small proportion of older people(>60 years)also had ultra-high HBV viral load(4.3%).9.1%and 6.7%of individuals with ultra-high HBV viral load showed FIB-4>3.25 and aMAP≥50,respectively.In the traditional stages of CHB,which are based on HBeAg and alanine aminotransferase(ALT)[the upper limit of normal(ULN)ALT level at 40 IU/L for both men and women],regardless of phase,a certain proportion of patients were at risk of developing HCC(4.1%,6.4%,25.0%,and 20.3%).However,in the new‘eALT-F’stages,which are based on HBeAg,ALT(the ULN of ALT level at 30 IU/L for men and 19 IU/L for women),and/or FIB-4 levels(>1.45),aMAP≥50 was only observed in chronic hepatitis patients with positive or negative HBeAg(6.4%and 22.1%,respectively).Conclusions:The‘eALT-F’staging method,based on HBeAg,ALT(males:the ULN of ALT was 30 IU/L,females:19 IU/L)and/or FIB-4 levels,was more effective in identifying medium to high-risk patients with HCC from patients with ultra-high HBV viral load than the traditional staging methods.
文摘●The Ministry of Education Research Center for Online Education conducted a national survey of university administrators of learning and teaching.●The survey results showed that(a)the universities in eastern China had developed and introduced more massive open online courses(MOOCs)than those in the central and western regions;(b)of the various measures for blended learning,the universities tended to focus on supporting hardware development before providing training and incentive measures to teachers;and(c)the universities had widely used hybrid learning approaches.In relation to hybrid learning,Tsinghua University explored infrastructure upgrades,teacher training,and the optimal use of the rain classroom and its clone class,and launched the global hybrid classroom and global open courses.●In the future,it will be necessary to further promote education equity in line with national policies and provide and perfect incentives to improve the quality of blended learning and expand hybrid learning while improving interaction through technology.
