Accurate forecasting of traffic flow provides a powerful traffic decision-making basis for an intelligent transportation system. However, the traffic data's complexity and fluctuation, as well as the noise produce...Accurate forecasting of traffic flow provides a powerful traffic decision-making basis for an intelligent transportation system. However, the traffic data's complexity and fluctuation, as well as the noise produced during collecting information and summarizing original data of traffic flow, cause large errors in the traffic flow forecasting results. This article suggests a solution to the above mentioned issues and proposes a fully connected time-gated neural network based on wavelet reconstruction(WT-FCTGN). To eliminate the potential noise and strengthen the potential traffic trend in the data, we adopt the methods of wavelet reconstruction and periodic data introduction to preprocess the data. The model introduces fully connected time-series blocks to model all the information including time sequence information and fluctuation information in the flow of traffic, and establishes the time gate block to comprehend the periodic characteristics of the flow of traffic and predict its flow. The performance of the WT-FCTGN model is validated on the public Pe MS data set. The experimental results show that the WT-FCTGN model has higher accuracy, and its mean absolute error(MAE), mean absolute percentage error(MAPE) and root mean square error(RMSE) are obviously lower than those of the other algorithms. The robust experimental results prove that the WT-FCTGN model has good anti-noise ability.展开更多
Osteoarthritis(OA) causes the destruction of joints. Its pathogenesis is still under investigation, and there is no effective diseasemodifying therapy. Here, we report that elevated cyclooxygenase-2(COX-2) expression ...Osteoarthritis(OA) causes the destruction of joints. Its pathogenesis is still under investigation, and there is no effective diseasemodifying therapy. Here, we report that elevated cyclooxygenase-2(COX-2) expression in the osteocytes of subchondral bone causes both spontaneous OA and rheumatoid arthritis(RA). The knockout of COX-2 in osteocytes or treatment with a COX-2 inhibitor effectively rescues the structure of subchondral bone and attenuates cartilage degeneration in spontaneous OA(STR/Ort)mice and tumor necrosis factor-α transgenic RA mice. Thus, elevated COX-2 expression in subchondral bone induces both OAassociated and RA-associated joint cartilage degeneration. The inhibition of COX-2 expression can potentially modify joint destruction in patients with arthritis.展开更多
Nine years(2001–2009)of data from the Cluster spacecraft are analyzed in this study of the Earth’s mid-and high-altitude(2–9RE)cusp.Properties of the cusp region,and its location and size in the Solar Magnetic coor...Nine years(2001–2009)of data from the Cluster spacecraft are analyzed in this study of the Earth’s mid-and high-altitude(2–9RE)cusp.Properties of the cusp region,and its location and size in the Solar Magnetic coordinate system,are studied statistically.The survey shows that(1)the relationships between X and Z are nearly linear for the poleward,equatorward boundaries and the center of the cusp;(2)the relationship between cusp width in the X direction and Z can be expressed by a quadratic function;(3)the cusp region is almost dawn-dusk symmetric for the cusp width in the X direction.Based on topology information,a new normalized statistical methodology is developed to organize the measurements of cusp crossings to obtain distributions of magnetic field and plasma parameters in the XZ plane.The statistical results show that(1)Bx is mostly negative and Bz is always negative;(2)proton velocity is found to be positive for Vx and Vz at low altitudes,while Vx and Vz are negative on the equator side and negative Vx and positive Vz on the pole side at high altitudes;(3)proton density is higher on the equator side than on the pole side.Results reported here will be useful in suggesting directions for future cusp research.展开更多
Two THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft,B and C,began orbiting the Moon in 2011 and have since provided routine measurements of the plasma conditions in the lunar orbi...Two THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft,B and C,began orbiting the Moon in 2011 and have since provided routine measurements of the plasma conditions in the lunar orbit.In this study,we systematically compare these measurements in near-Earth space with solar wind measurements obtained from the Lagrangian 1(L1)point and propagated to the Earth,including measurements in the OMNI database and from the Wind spacecraft.A statistical comparison between THEMIS data and data from the OMNI database from September 2011 to December 2017 showed that the Y and Z components of the magnetic field and the flow speed are generally consistent between the two data sets.The ion number density and the dynamic pressure measured by THEMIS in near-Earth space are lower than those in the OMNI database,suggesting possible variation in the solar wind environment while propagating from the L1 point to near-Earth space.We further show two examples in which near-Earth solar wind measurements are applied in calculating the magnetopause location and in quantifying the magnetic field response to interplanetary shocks.Both examples suggest that using solar wind data from near-Earth space achieves better results than using solar wind data from the L1 point.These results provide validation of THEMIS-B and THEMIS-C as an alternative monitor of the near-Earth solar wind environment.展开更多
The cultivation of top-notch innovative talents is one of the most prominent tasks in China s universities in the new era,and also an opportunity and challenge for local universities.Taking the food subject of local u...The cultivation of top-notch innovative talents is one of the most prominent tasks in China s universities in the new era,and also an opportunity and challenge for local universities.Taking the food subject of local universities as an example,some suggestions were put forward from the aspects of security measures,teacher team construction,talent selection and management,and talent cultivation,in order to provide reference for the exploration and practice of cultivating top-notch innovative talents in the food subject of local universities.展开更多
A continuous hot embossing method is reported in this paper. The continuous means that the extruder and the hot embossing equipment is used in series, the polymer film is embossed after extrusion immediately. The basi...A continuous hot embossing method is reported in this paper. The continuous means that the extruder and the hot embossing equipment is used in series, the polymer film is embossed after extrusion immediately. The basic principle of this method, the key design point and the corresponding operate process of the embossing equipment is described in this paper. The polymer diffuser with micro-lens matrix on its surface is designed and the optical properties are simulated. Then, the diffuser is fabricated by the embossing equipment. The optical properties of the diffuser are tested and compared with the results of the simulation to verify the reproducibility of the equipment. By this method, the diffuser with large area can be fabricated with high precision of graphic replication, high efficiency and low cost.展开更多
In this work,novel D-A alternating polymers(PJ-1,PJ-2,and PJ-3)with chlorinated benzodithiophene and chlorinated thiazole units were synthesized via gradual chlorination.These polymers could be obtained readily throug...In this work,novel D-A alternating polymers(PJ-1,PJ-2,and PJ-3)with chlorinated benzodithiophene and chlorinated thiazole units were synthesized via gradual chlorination.These polymers could be obtained readily through a few concise synthesis steps.Among them,PJ-1 displayed desirable properties including energy levels,crystallinity,and charge transport capabilities.The binary and ternary organic solar cells(OSCs)fabricated based on PJ-1 displayed significant power conversion efficiency(PCE)of 15.02%and 19.12%,respectively,placing them among the highest reported for ternary OSCs.Notably,the PJ1-based devices also showcased one of the highest figure-of-merit values,indicating their promising potential for future applications.This study offers valuable insights and supports the development of costeffective and high-performance polymer donors for the generation of OSCs.展开更多
The side-chain has a significant influence on the optical properties and aggregation behaviors of the organic small molecule acceptors,which becomes an important strategy to optimize the photovoltaic performance of or...The side-chain has a significant influence on the optical properties and aggregation behaviors of the organic small molecule acceptors,which becomes an important strategy to optimize the photovoltaic performance of organic solar cells.In this work,we designed and synthesized three brand-new nonfused ring electron acceptors(NFREAs)OC4-4Cl-Ph,OC4-4Cl-Th,and OC4-4Cl-C8 with hexylbenzene,hexylthiophene,and octyl side chains on theπ-bridge units.Compared with OC4-4Cl-Ph and OC4-4Cl-Th,OC4-4Cl-C8 with linear alkyl side chain has more red-shift absorption,which is conducive to obtaining higher short-circuit current density.Additionally,the OC4-4Cl-C8 film exhibits a longer exciton diffusion distance,and the D18:OC4-4Cl-C8 blend film displays faster hole transfer,weaker bimolecular recombination,and more efficient exciton transport.Furthermore,The D18:OC4-4Cl-C8 blend films may effectively form interpenetrating networks that resemble nanofibrils,which can facilitate exciton dissociation and charge transport.Finally,OC4-4Cl-C8-based devices can be created a marvellously power conversion efficiency(PCE)of 16.56%,which is much higher than OC4-4Cl-Ph(12.29%)-and OC4-4Cl-Th-based(11.00%)ones,being the highest PCE among the NFREA based binary devices.All in all,we have validated that side-chain engineering is an efficient way to achieve high-performance NFREAs.展开更多
In the preparation of large-sized ceramics,the use of a green body with relatively high plasticity is crucial to minimize the risk of cracking during processing.To achieve this goal,glycerol and polyethylene glycol(PE...In the preparation of large-sized ceramics,the use of a green body with relatively high plasticity is crucial to minimize the risk of cracking during processing.To achieve this goal,glycerol and polyethylene glycol(PEG)were utilized as plasticizers in the shaping of green bodies of oxide ceramics through spontaneous coagulation casting(SCC).This study investigated the effects of plasticizers and particle sizes ranging from the submicron to nanoscale on the slurry viscosity,drying shrinkage of wet gels,and mechanical properties of green bodies.The plasticity of the green bodies was assessed by measuring the impact toughness and flexural stress‒strain curves.By incorporating an appropriate plasticizer,the peak width of the flexural stress‒strain curve for dried green bodies from particles of different sizes was nearly twice that without plasticizers,and the impact toughness was enhanced by approximately 71%,34%,and 41%when the particle size decreased from the submicron scale to the nanoscale(0.45μm,0.18μm,and 50 nm,respectively).The drilling test revealed that there was nearly no cracking around the holes in the green bodies with plasticizers.The plasticity mechanism of the green bodies was examined based on ultraviolet–visible(UV–Vis)spectroscopy and scanning electron microscopy(SEM).It was discovered that plasticizers might mitigate the brittleness of green bodies by adjusting the interactions between molecules and modifying the gel network properly.展开更多
The addition of traditional carbon sources(e.g.,acetate)could favor heterotrophic overgrowth in partial denitrification coupled with anammox(PD–A)systems,thus hindering the performance and stability of this novel was...The addition of traditional carbon sources(e.g.,acetate)could favor heterotrophic overgrowth in partial denitrification coupled with anammox(PD–A)systems,thus hindering the performance and stability of this novel wastewater nitrogen removal technology.Therefore,it is necessary to develop an effective,environmentally friendly,and inexpensive alternative.This study demonstrated the potential of formate to enhance the performance and community stability of PD–A under mainstream conditions.In a laboratory-scale biofilm reactor,formate addition(COD/NO_(3)^(–)–N=1.75)improved nitrogen removal efficiency(from 72.1±3.5%to 81.7±2.7%),EPS content(from 106.3±8.1 to 163.0±15.5 mg/gVSS)and increased anammox bacteria growth(predominantly Candidatus Brocadia,from 29.5±0.7%to 34.5±5.4%)while maintaining stable heterotrophs dominated by methylotrophic Desulfobacillus.FISH–NanoSIMS revealed a formate uptake using Ca.Brocadia and Desulfobacillus,with Ca.Brocadia being the major contributor to partial nitrate reduction to nitrite.Desulfobacillus can synthesize diverse hydrophobic amino acids and provide key nutrients for Ca.Brocadia.To achieve comparable nitrogen removal,the cost of the formate-driven PD–A process should be 11.2%lower than that of acetate.These results greatly enrich our understanding of C1 metabolism represented by formate in anammox communities and its application in the context of coupling partial denitrification–anammox toward enhanced nitrogen removal in global wastewater treatment systems.展开更多
The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and ...The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the Li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free LMAs.The Ni foam offers abundant space to receive deposited Li metal.The CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of Li^(+)reduction.Moreover,the nanosheet structure with lithiophilicity would accelerate the move of Li+and decrease the nucleation barrier,due to the high lattice-matching of Li and CoN.Meanwhile,the CoF_(2) could increase the content of F(LiF)in the SEI layer,which enhances the strength and avoids the destruction of SEI layer.With the cooperation of CoN and CoF_(2),the composited anode(Li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the LiFePO_(4) and Li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic efficiency.The strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.展开更多
Objectives Older individuals with multimorbidity are at an elevated risk of infection and complications from COVID-19.Effectiveness of post-COVID-19 interventions or care models in reducing subsequent adverse outcomes...Objectives Older individuals with multimorbidity are at an elevated risk of infection and complications from COVID-19.Effectiveness of post-COVID-19 interventions or care models in reducing subsequent adverse outcomes in these individuals have rarely been examined.This study aims to examine the effectiveness of attending general outpatient within 30 days after discharge from COVID-19 on 1-year survival among older adults aged 85 years or above with multimorbidity.Design Retrospective cohort study emulating a randomised target trial using electronic health records.Setting We used data from the Hospital Authority and the Department of Health in Hong Kong,which provided comprehensive electronic health records,COVID-19 confirmed case data,population-based vaccination records and other individual characteristics for the study.Participants Adults aged 85 years or above with multimorbidity who were discharged after hospitalisation for COVID-19 between January 2020 and August 2022.Interventions Attending a general outpatient within 30 days of last COVID-19 discharge defined the exposure,compared to no outpatient visit.Main outcome measures Primary outcome was all-cause mortality within one year.Secondary outcomes included mortality from respiratory,cardiovascular and cancer causes.Results A total of 6183 eligible COVID-19 survivors were included in the analysis.The all-cause mortality rate following COVID-19 hospitalisation was lower in the general outpatient visit group(17.1 deaths per 100 person-year)compared with non-visit group(42.8 deaths per 100 person-year).After adjustment,primary care consultations within 30 days after discharge were associated with a significantly greater 1-year survival(difference in 1-year survival:11.2%,95%CI 8.1%to 14.4%).We also observed significantly better survival from respiratory diseases in the general outpatient visit group(difference in 1-year survival:6.3%,95%CI 3.5%to 8.9%).In a sensitivity analysis for different grace period lengths,we found that the earlier participants had a general outpatient visit after COVID-19 discharge,the better the survival.Conclusions Timely primary care consultations after COVID-19 hospitalisation may improve survival following COVID-19 hospitalisation among older adults aged 85 or above with multimorbidity.Expanding primary care services and implementing follow-up mechanisms are crucial to support this vulnerable population’s recovery and well-being.展开更多
During last decades, sensor elements based on the fiber Bragg grating (FBG) have been widely studied and developed due to the advantages of immunity to electromagnetic interference, compact size, high precision, and...During last decades, sensor elements based on the fiber Bragg grating (FBG) have been widely studied and developed due to the advantages of immunity to electromagnetic interference, compact size, high precision, and so on. The FBG itself is sensitive to axial strain and temperature variation directly and can indirectly measure these complex physical parameters, such as pressure, displacement, and vibration, by using some specially designed elastic structures to convert them into the axial strain of the FBG. Whether the FBG is fixed on the measured object to measure the strain directly or fixed on an elastic structure body to measure other physical quantities, these types of FBGs could be collectively called as strain sensing FBGs. The packaging of the FBG has important influence on FBG characteristics that directly affect the measurement accuracy, such as strain transfer, temperature characteristic, and spectral shape. This paper summarizes the packaging methods and corresponding temperature compensation methods of the currently reported strain sensing FBGs, focusing especially on fully pasted FBG, pre-stretched FBG with double-end fixed, and metallic packaging. Furthermore, the advantages and drawbacks of different packaging methods have been analyzed, which can provide a reference for future researches.展开更多
Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are pro...Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are promising for the applications in flexible and wearable devices,such as flexible sensors,flexible detectors,flexible oscillators,flexible spintronics,wearable displays and electronic skin,etc.This review aims to summarize the fabrication,physical properties and applications of the flexible oxide epitaxial thin films for wearable electronics in most recent few years.The fabrication of flexible oxide epitaxial thin films reviewed here mainly includes the deposition on flexible substrates at high temperature and epitaxial lift-off(ELO)from rigid substrates.The physical properties and applications of flexible oxide epitaxial thin films reviewed here chiefly focus on the area of electricity and magnetism,including stable and tunable physical properties in the flexible oxide epitaxial thin films.In final,the perspectives and challenges of flexible oxide thin films for wearable electronics have been also addressed.展开更多
There is a need for synthetic grafts to reconstruct large bone defects using minimal invasive surgery.Our previous study showed that incorporation of Sr into bioactive borate glass cement enhanced the osteogenic capac...There is a need for synthetic grafts to reconstruct large bone defects using minimal invasive surgery.Our previous study showed that incorporation of Sr into bioactive borate glass cement enhanced the osteogenic capacity in vivo.However,the amount of Sr in the cement to provide an optimal combination of physicochemical properties and capacity to stimulate bone regeneration and the underlying molecular mechanism of this stimulation is yet to be determined.In this study,bone cements composed of bioactive borosilicate glass particles substituted with varying amounts of Sr(0 mol%to 12 mol%SrO)were created and evaluated in vitro and in vivo.The setting time of the cement increased with Sr substitution of the glass.Upon immersion in PBS,the cement degraded and converted more slowly to HA(hydroxyapatite)with increasing Sr substitution.The released Sr2+modulated the proliferation,differentiation,and mineralization of hBMSCs(human bone marrow mesenchymal stem cells)in vitro.Osteogenic characteristics were optimally enhanced with cement(designated BG6Sr)composed of particles substituted with 6mol%SrO.When implanted in rabbit femoral condyle defects,BG6Sr cement supported better peri-implant bone formation and bone-implant contact,comparing to cements substituted with 0mol%or 9mol%SrO.The underlying mechanism is involved in the activation of Wnt/β-catenin signaling pathway in osteogenic differentiation of hBMSCs.These results indicate that BG6Sr cement has a promising combination of physicochemical properties and biological performance for minimally invasive healing of bone defects.展开更多
Dielectrics used for energy storage are highly desired for power electronics and pulse power applications and the polymer capacitors are the main commercial ones available.The development of flexible electronics and w...Dielectrics used for energy storage are highly desired for power electronics and pulse power applications and the polymer capacitors are the main commercial ones available.The development of flexible electronics and wearable devices require the relative materials being flexible.Besides,high temperature resistance is also desired because of the rising demand for high power devices and large electricity under elevated temperature.The polymer dielectrics for polymer capacitors are flexible but with relatively low working temperature normally less than 100℃.Therefore,fabricating a dielectric material to satisfy the flexibility and high working temperature simultaneously is still a great challenge.Here we propose one solution by demonstrating a hand-exfoliated fluorophlogopite film with micrometer scale thickness.Among which,the mica film with a thickness of around 10μm(Mica-10)exhibits the inorganic-like temperature stability even polymer-like flexibility.From 25℃to 200℃,Mica-10 has an energy density of around 11.27 J/cm^(3)with a variation within 2%,accompanied by a charge-discharge efficiency of around 95%at an electric field of 500 MV/m.Meanwhile,the thin thickness makes Mica-10 flexible,enabling its excellent flexibility and durability.This work revives the traditional material,mica,providing a way for high-temperature energy storage applications.展开更多
Bil_xTbxFe03 thin films were prepared on Sn02 (fluorine doped tin oxide) substrates by a sol-gel method. The structural and electrical properties of the BiFe03 thin films were characterized and tested. The results i...Bil_xTbxFe03 thin films were prepared on Sn02 (fluorine doped tin oxide) substrates by a sol-gel method. The structural and electrical properties of the BiFe03 thin films were characterized and tested. The results indicated that the diffraction peak of the Tb-doped BiFe03 films was shifted towards right as the doping amounts were increased. The structure was transformed from the rhombohedral to tetragonal/orthorhombic phase. The Bio.sgTbo.11Fe03 thin film showed the well-developed P-E loops, which enhanced remnant polarization (Pr = 88.05 μC/cm2) at room temperature. The dielectric constant and dielectric loss of Bio.sgTbo.llFe03 thin film at 100 kHz were 185 and 0.018, respectively. Furthermore, the Bio.seTbo.llFe03 thin film showed a relatively low leakage current density of 2.07×10-5 A/cm2 at an applied electric field of 150 kV/cm. The X- ray photoelectron spectroscopy (XPS) spectra indicated that the presence of Fe2+ ions in the Bio.egTbo.11Fe03 thin film was less than that in the pure BiFe03.展开更多
In osteoporosis scenario, tissue response to implants is greatly impaired by the deteriorated boneregeneration microenvironment. In the present study, a Mg-containing akermanite (Ak) ceramic wasemployed for the treatm...In osteoporosis scenario, tissue response to implants is greatly impaired by the deteriorated boneregeneration microenvironment. In the present study, a Mg-containing akermanite (Ak) ceramic wasemployed for the treatment of osteoporotic bone defect, based on the hypothesis that both beneficialions (e.g. Mg^2+ ect.) released by the implants and the weak alkaline microenvironment pH (μe-pH) itcreated may play distinct roles in recovering the abnormal bone regeneration by stimulating osteoblasticanabolic effects. The performance of Ak, b-tricalcium phosphate (β-TCP) and Hardystone (Har) in healinga 3 mm bone defect on the ovariectomized (OVX) osteoporotic rat model was evaluated. Our resultsindicated that, there's more new bone formed in Ak group than in β-TCP or Har group at week 9. Theinitial me-pHs of Ak were significantly higher than that of the β-TCP and Blank group, and this weakalkaline condition was maintained till at least 9 weeks post-surgery. Increased osteoblastic activity whichwas indicated by higher osteoid secretion was observed in Ak group at week 4 to week 9. An intermediatelayer which was rich in phosphorus minerals and bound directly to the new forming bone wasdeveloped on the surface of Ak. In a summary, our study demonstrates that Ak exhibits a superior boneregenerative performance under osteoporosis condition, and might be a promising candidate for thetreatment of osteoporotic bone defect and fracture.展开更多
基金The Science and Technology Research and Development Program Project of China Railway Group Ltd provided funding for this study(Project Nos.2020-Special-02 and 2021Special-08)。
文摘Accurate forecasting of traffic flow provides a powerful traffic decision-making basis for an intelligent transportation system. However, the traffic data's complexity and fluctuation, as well as the noise produced during collecting information and summarizing original data of traffic flow, cause large errors in the traffic flow forecasting results. This article suggests a solution to the above mentioned issues and proposes a fully connected time-gated neural network based on wavelet reconstruction(WT-FCTGN). To eliminate the potential noise and strengthen the potential traffic trend in the data, we adopt the methods of wavelet reconstruction and periodic data introduction to preprocess the data. The model introduces fully connected time-series blocks to model all the information including time sequence information and fluctuation information in the flow of traffic, and establishes the time gate block to comprehend the periodic characteristics of the flow of traffic and predict its flow. The performance of the WT-FCTGN model is validated on the public Pe MS data set. The experimental results show that the WT-FCTGN model has higher accuracy, and its mean absolute error(MAE), mean absolute percentage error(MAPE) and root mean square error(RMSE) are obviously lower than those of the other algorithms. The robust experimental results prove that the WT-FCTGN model has good anti-noise ability.
基金supported by the NIH/NIAMS grants AR071432 and AR063943 (to X.C.)
文摘Osteoarthritis(OA) causes the destruction of joints. Its pathogenesis is still under investigation, and there is no effective diseasemodifying therapy. Here, we report that elevated cyclooxygenase-2(COX-2) expression in the osteocytes of subchondral bone causes both spontaneous OA and rheumatoid arthritis(RA). The knockout of COX-2 in osteocytes or treatment with a COX-2 inhibitor effectively rescues the structure of subchondral bone and attenuates cartilage degeneration in spontaneous OA(STR/Ort)mice and tumor necrosis factor-α transgenic RA mice. Thus, elevated COX-2 expression in subchondral bone induces both OAassociated and RA-associated joint cartilage degeneration. The inhibition of COX-2 expression can potentially modify joint destruction in patients with arthritis.
基金the National Natural Science Foundation of China,grants 41821003,41974194 and 41574154.
文摘Nine years(2001–2009)of data from the Cluster spacecraft are analyzed in this study of the Earth’s mid-and high-altitude(2–9RE)cusp.Properties of the cusp region,and its location and size in the Solar Magnetic coordinate system,are studied statistically.The survey shows that(1)the relationships between X and Z are nearly linear for the poleward,equatorward boundaries and the center of the cusp;(2)the relationship between cusp width in the X direction and Z can be expressed by a quadratic function;(3)the cusp region is almost dawn-dusk symmetric for the cusp width in the X direction.Based on topology information,a new normalized statistical methodology is developed to organize the measurements of cusp crossings to obtain distributions of magnetic field and plasma parameters in the XZ plane.The statistical results show that(1)Bx is mostly negative and Bz is always negative;(2)proton velocity is found to be positive for Vx and Vz at low altitudes,while Vx and Vz are negative on the equator side and negative Vx and positive Vz on the pole side at high altitudes;(3)proton density is higher on the equator side than on the pole side.Results reported here will be useful in suggesting directions for future cusp research.
基金supported by the National Natural Science Foundation of China (grants 41821003 and 41974194)
文摘Two THEMIS(Time History of Events and Macroscale Interactions during Substorms)spacecraft,B and C,began orbiting the Moon in 2011 and have since provided routine measurements of the plasma conditions in the lunar orbit.In this study,we systematically compare these measurements in near-Earth space with solar wind measurements obtained from the Lagrangian 1(L1)point and propagated to the Earth,including measurements in the OMNI database and from the Wind spacecraft.A statistical comparison between THEMIS data and data from the OMNI database from September 2011 to December 2017 showed that the Y and Z components of the magnetic field and the flow speed are generally consistent between the two data sets.The ion number density and the dynamic pressure measured by THEMIS in near-Earth space are lower than those in the OMNI database,suggesting possible variation in the solar wind environment while propagating from the L1 point to near-Earth space.We further show two examples in which near-Earth solar wind measurements are applied in calculating the magnetopause location and in quantifying the magnetic field response to interplanetary shocks.Both examples suggest that using solar wind data from near-Earth space achieves better results than using solar wind data from the L1 point.These results provide validation of THEMIS-B and THEMIS-C as an alternative monitor of the near-Earth solar wind environment.
基金Supported by the Education Reform Project of Chengdu University (cdjgb2022123).
文摘The cultivation of top-notch innovative talents is one of the most prominent tasks in China s universities in the new era,and also an opportunity and challenge for local universities.Taking the food subject of local universities as an example,some suggestions were put forward from the aspects of security measures,teacher team construction,talent selection and management,and talent cultivation,in order to provide reference for the exploration and practice of cultivating top-notch innovative talents in the food subject of local universities.
文摘A continuous hot embossing method is reported in this paper. The continuous means that the extruder and the hot embossing equipment is used in series, the polymer film is embossed after extrusion immediately. The basic principle of this method, the key design point and the corresponding operate process of the embossing equipment is described in this paper. The polymer diffuser with micro-lens matrix on its surface is designed and the optical properties are simulated. Then, the diffuser is fabricated by the embossing equipment. The optical properties of the diffuser are tested and compared with the results of the simulation to verify the reproducibility of the equipment. By this method, the diffuser with large area can be fabricated with high precision of graphic replication, high efficiency and low cost.
基金Financial support was received from the National Natural Science Foundation of China (grant nos.22109080,51933001,and 52173174)the Natural Science Foundation of Shandong Province (grant no.ZR2022YQ45)+1 种基金the Taishan Scholars Program (grant nos.tsqnz20221134 and tstp20221121)the State Key Laboratory of Bio-Fibers and Eco-Textiles of Qingdao University (grant no.RZ2200002821).
文摘In this work,novel D-A alternating polymers(PJ-1,PJ-2,and PJ-3)with chlorinated benzodithiophene and chlorinated thiazole units were synthesized via gradual chlorination.These polymers could be obtained readily through a few concise synthesis steps.Among them,PJ-1 displayed desirable properties including energy levels,crystallinity,and charge transport capabilities.The binary and ternary organic solar cells(OSCs)fabricated based on PJ-1 displayed significant power conversion efficiency(PCE)of 15.02%and 19.12%,respectively,placing them among the highest reported for ternary OSCs.Notably,the PJ1-based devices also showcased one of the highest figure-of-merit values,indicating their promising potential for future applications.This study offers valuable insights and supports the development of costeffective and high-performance polymer donors for the generation of OSCs.
基金National Natural Science Foundation of China,Grant/Award Numbers:52173174,51933001,22109080Natural Science Foundation of Shandong Province,Grant/Award Number:ZR2022YQ45Taishan Scholars Program,Grant/Award Numbers:tstp20221121,tsqnz20221134。
文摘The side-chain has a significant influence on the optical properties and aggregation behaviors of the organic small molecule acceptors,which becomes an important strategy to optimize the photovoltaic performance of organic solar cells.In this work,we designed and synthesized three brand-new nonfused ring electron acceptors(NFREAs)OC4-4Cl-Ph,OC4-4Cl-Th,and OC4-4Cl-C8 with hexylbenzene,hexylthiophene,and octyl side chains on theπ-bridge units.Compared with OC4-4Cl-Ph and OC4-4Cl-Th,OC4-4Cl-C8 with linear alkyl side chain has more red-shift absorption,which is conducive to obtaining higher short-circuit current density.Additionally,the OC4-4Cl-C8 film exhibits a longer exciton diffusion distance,and the D18:OC4-4Cl-C8 blend film displays faster hole transfer,weaker bimolecular recombination,and more efficient exciton transport.Furthermore,The D18:OC4-4Cl-C8 blend films may effectively form interpenetrating networks that resemble nanofibrils,which can facilitate exciton dissociation and charge transport.Finally,OC4-4Cl-C8-based devices can be created a marvellously power conversion efficiency(PCE)of 16.56%,which is much higher than OC4-4Cl-Ph(12.29%)-and OC4-4Cl-Th-based(11.00%)ones,being the highest PCE among the NFREA based binary devices.All in all,we have validated that side-chain engineering is an efficient way to achieve high-performance NFREAs.
基金the National Natural Science Foundation of China(No.52130207).
文摘In the preparation of large-sized ceramics,the use of a green body with relatively high plasticity is crucial to minimize the risk of cracking during processing.To achieve this goal,glycerol and polyethylene glycol(PEG)were utilized as plasticizers in the shaping of green bodies of oxide ceramics through spontaneous coagulation casting(SCC).This study investigated the effects of plasticizers and particle sizes ranging from the submicron to nanoscale on the slurry viscosity,drying shrinkage of wet gels,and mechanical properties of green bodies.The plasticity of the green bodies was assessed by measuring the impact toughness and flexural stress‒strain curves.By incorporating an appropriate plasticizer,the peak width of the flexural stress‒strain curve for dried green bodies from particles of different sizes was nearly twice that without plasticizers,and the impact toughness was enhanced by approximately 71%,34%,and 41%when the particle size decreased from the submicron scale to the nanoscale(0.45μm,0.18μm,and 50 nm,respectively).The drilling test revealed that there was nearly no cracking around the holes in the green bodies with plasticizers.The plasticity mechanism of the green bodies was examined based on ultraviolet–visible(UV–Vis)spectroscopy and scanning electron microscopy(SEM).It was discovered that plasticizers might mitigate the brittleness of green bodies by adjusting the interactions between molecules and modifying the gel network properly.
基金funded by the Zhejiang Provincial Natural Science Foundation of China(No.LR23B070002)the General Program of the National Natural Science Foundation of China(No.22276165).
文摘The addition of traditional carbon sources(e.g.,acetate)could favor heterotrophic overgrowth in partial denitrification coupled with anammox(PD–A)systems,thus hindering the performance and stability of this novel wastewater nitrogen removal technology.Therefore,it is necessary to develop an effective,environmentally friendly,and inexpensive alternative.This study demonstrated the potential of formate to enhance the performance and community stability of PD–A under mainstream conditions.In a laboratory-scale biofilm reactor,formate addition(COD/NO_(3)^(–)–N=1.75)improved nitrogen removal efficiency(from 72.1±3.5%to 81.7±2.7%),EPS content(from 106.3±8.1 to 163.0±15.5 mg/gVSS)and increased anammox bacteria growth(predominantly Candidatus Brocadia,from 29.5±0.7%to 34.5±5.4%)while maintaining stable heterotrophs dominated by methylotrophic Desulfobacillus.FISH–NanoSIMS revealed a formate uptake using Ca.Brocadia and Desulfobacillus,with Ca.Brocadia being the major contributor to partial nitrate reduction to nitrite.Desulfobacillus can synthesize diverse hydrophobic amino acids and provide key nutrients for Ca.Brocadia.To achieve comparable nitrogen removal,the cost of the formate-driven PD–A process should be 11.2%lower than that of acetate.These results greatly enrich our understanding of C1 metabolism represented by formate in anammox communities and its application in the context of coupling partial denitrification–anammox toward enhanced nitrogen removal in global wastewater treatment systems.
基金supported by the Fundamental Research Funds for the Central Universities(No.3132023503).
文摘The notorious dendrite and infinite volume change seriously restrict the advancement of lithium metal anodes(LMAs),during the long-term process of stripping/plating.Herein,the nanosheets of metal fluoride(CoF_(2))and metal nitride(CoN)with magnificent lithiophilicity on the nickel(Ni)foam are designed as the“regulator”to uniform the Li plating and build stronger solid electrolyte interface(SEI)layer for dendrite free LMAs.The Ni foam offers abundant space to receive deposited Li metal.The CoN nanosheets can guarantee the fast transfer of electrons,which provides a stable interface of Li^(+)reduction.Moreover,the nanosheet structure with lithiophilicity would accelerate the move of Li+and decrease the nucleation barrier,due to the high lattice-matching of Li and CoN.Meanwhile,the CoF_(2) could increase the content of F(LiF)in the SEI layer,which enhances the strength and avoids the destruction of SEI layer.With the cooperation of CoN and CoF_(2),the composited anode(Li/NF@CNCF)exhibits ultra-long cycle performance(more than 1200 h)and fantastic structure stability at 1 mA·cm^(-2) with 1 mAh·cm^(-2).Based on the LiFePO_(4) and Li/NF@CNCF,the full cells deliver excellent specifical capacity and steady coulombic efficiency.The strategy contributes an effective approach to alleviate the issues of lithium metal anodes in the field of LMAs.
基金funded by a research grant from the Health Bureau of the Government of the Hong Kong Special Administrative Region,through the Health and Medical Research Fund Research on COVID-19(COVID19F01)supported by the Laboratory of Data Discovery for Health,funded by the AIR@InnoHK and administered by the Innovation and Technology Commission.
文摘Objectives Older individuals with multimorbidity are at an elevated risk of infection and complications from COVID-19.Effectiveness of post-COVID-19 interventions or care models in reducing subsequent adverse outcomes in these individuals have rarely been examined.This study aims to examine the effectiveness of attending general outpatient within 30 days after discharge from COVID-19 on 1-year survival among older adults aged 85 years or above with multimorbidity.Design Retrospective cohort study emulating a randomised target trial using electronic health records.Setting We used data from the Hospital Authority and the Department of Health in Hong Kong,which provided comprehensive electronic health records,COVID-19 confirmed case data,population-based vaccination records and other individual characteristics for the study.Participants Adults aged 85 years or above with multimorbidity who were discharged after hospitalisation for COVID-19 between January 2020 and August 2022.Interventions Attending a general outpatient within 30 days of last COVID-19 discharge defined the exposure,compared to no outpatient visit.Main outcome measures Primary outcome was all-cause mortality within one year.Secondary outcomes included mortality from respiratory,cardiovascular and cancer causes.Results A total of 6183 eligible COVID-19 survivors were included in the analysis.The all-cause mortality rate following COVID-19 hospitalisation was lower in the general outpatient visit group(17.1 deaths per 100 person-year)compared with non-visit group(42.8 deaths per 100 person-year).After adjustment,primary care consultations within 30 days after discharge were associated with a significantly greater 1-year survival(difference in 1-year survival:11.2%,95%CI 8.1%to 14.4%).We also observed significantly better survival from respiratory diseases in the general outpatient visit group(difference in 1-year survival:6.3%,95%CI 3.5%to 8.9%).In a sensitivity analysis for different grace period lengths,we found that the earlier participants had a general outpatient visit after COVID-19 discharge,the better the survival.Conclusions Timely primary care consultations after COVID-19 hospitalisation may improve survival following COVID-19 hospitalisation among older adults aged 85 or above with multimorbidity.Expanding primary care services and implementing follow-up mechanisms are crucial to support this vulnerable population’s recovery and well-being.
基金This paper was partially supported by the Natural Science Foundation of China under Grant No. 51605348, the Natural Science Foundation of Hubei province under Grants No. 2016CFB116, and the Project of China Postdoctoral Science Foundation under Grant No. 2015M572208.
文摘During last decades, sensor elements based on the fiber Bragg grating (FBG) have been widely studied and developed due to the advantages of immunity to electromagnetic interference, compact size, high precision, and so on. The FBG itself is sensitive to axial strain and temperature variation directly and can indirectly measure these complex physical parameters, such as pressure, displacement, and vibration, by using some specially designed elastic structures to convert them into the axial strain of the FBG. Whether the FBG is fixed on the measured object to measure the strain directly or fixed on an elastic structure body to measure other physical quantities, these types of FBGs could be collectively called as strain sensing FBGs. The packaging of the FBG has important influence on FBG characteristics that directly affect the measurement accuracy, such as strain transfer, temperature characteristic, and spectral shape. This paper summarizes the packaging methods and corresponding temperature compensation methods of the currently reported strain sensing FBGs, focusing especially on fully pasted FBG, pre-stretched FBG with double-end fixed, and metallic packaging. Furthermore, the advantages and drawbacks of different packaging methods have been analyzed, which can provide a reference for future researches.
基金supported by the National Science Foundation of China(No.61631166004)Shenzhen KQTD project(No.KQTD20180411143514543)+1 种基金Shenzhen JCYJ project(No.JCYJ20180504165831308)and Shenzhen DRC project[2018]1433partially supported by Doctoral Scientific Research Startup Foundation of Shaanxi University of Science and Technology(No.2019BJ-30).
文摘Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are promising for the applications in flexible and wearable devices,such as flexible sensors,flexible detectors,flexible oscillators,flexible spintronics,wearable displays and electronic skin,etc.This review aims to summarize the fabrication,physical properties and applications of the flexible oxide epitaxial thin films for wearable electronics in most recent few years.The fabrication of flexible oxide epitaxial thin films reviewed here mainly includes the deposition on flexible substrates at high temperature and epitaxial lift-off(ELO)from rigid substrates.The physical properties and applications of flexible oxide epitaxial thin films reviewed here chiefly focus on the area of electricity and magnetism,including stable and tunable physical properties in the flexible oxide epitaxial thin films.In final,the perspectives and challenges of flexible oxide thin films for wearable electronics have been also addressed.
基金supported by the National Key R&D Program of China(Grant No.2018YFC1106300 , 2017YFC1105000)the National Natural Science Foundation of China(Grant No.51802340,31870956,31771041 , 81672227)+6 种基金the Science and Technology Project of Guangdong Province-Doctoral startup fund of 2017(Grant No.2017A030310318)the Frontier Science Key Research Programs of CAS(Grant No.QYZDB-SSW-JSC030)the Strategic Priority Research Program of CAS(Grant No.XDA16021000)the Shenzhen significant strategy layout project(Grant No.JCYJ20170413162104773)the Economic,Trade and information Commission of Shenzhen Municipality“Innovation and Industry Chain”(Grant No.20170502171625936)the Beijing Municipal Natural Science Foundation(Grant No.7161001)Beijing Municipal Commission of Health and Family Planning(Grant No.PXM2018_026275_000001).
文摘There is a need for synthetic grafts to reconstruct large bone defects using minimal invasive surgery.Our previous study showed that incorporation of Sr into bioactive borate glass cement enhanced the osteogenic capacity in vivo.However,the amount of Sr in the cement to provide an optimal combination of physicochemical properties and capacity to stimulate bone regeneration and the underlying molecular mechanism of this stimulation is yet to be determined.In this study,bone cements composed of bioactive borosilicate glass particles substituted with varying amounts of Sr(0 mol%to 12 mol%SrO)were created and evaluated in vitro and in vivo.The setting time of the cement increased with Sr substitution of the glass.Upon immersion in PBS,the cement degraded and converted more slowly to HA(hydroxyapatite)with increasing Sr substitution.The released Sr2+modulated the proliferation,differentiation,and mineralization of hBMSCs(human bone marrow mesenchymal stem cells)in vitro.Osteogenic characteristics were optimally enhanced with cement(designated BG6Sr)composed of particles substituted with 6mol%SrO.When implanted in rabbit femoral condyle defects,BG6Sr cement supported better peri-implant bone formation and bone-implant contact,comparing to cements substituted with 0mol%or 9mol%SrO.The underlying mechanism is involved in the activation of Wnt/β-catenin signaling pathway in osteogenic differentiation of hBMSCs.These results indicate that BG6Sr cement has a promising combination of physicochemical properties and biological performance for minimally invasive healing of bone defects.
基金The work was supported by the National 973 projects of China(No.2015CB654603)the National Natural Science Foundation of China(No.61471290,61631166004).
文摘Dielectrics used for energy storage are highly desired for power electronics and pulse power applications and the polymer capacitors are the main commercial ones available.The development of flexible electronics and wearable devices require the relative materials being flexible.Besides,high temperature resistance is also desired because of the rising demand for high power devices and large electricity under elevated temperature.The polymer dielectrics for polymer capacitors are flexible but with relatively low working temperature normally less than 100℃.Therefore,fabricating a dielectric material to satisfy the flexibility and high working temperature simultaneously is still a great challenge.Here we propose one solution by demonstrating a hand-exfoliated fluorophlogopite film with micrometer scale thickness.Among which,the mica film with a thickness of around 10μm(Mica-10)exhibits the inorganic-like temperature stability even polymer-like flexibility.From 25℃to 200℃,Mica-10 has an energy density of around 11.27 J/cm^(3)with a variation within 2%,accompanied by a charge-discharge efficiency of around 95%at an electric field of 500 MV/m.Meanwhile,the thin thickness makes Mica-10 flexible,enabling its excellent flexibility and durability.This work revives the traditional material,mica,providing a way for high-temperature energy storage applications.
基金supported by the Project of the National Natural Science Foundation of China(Grant No.51172135)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.51002092)+1 种基金Research and Special Projects of the Education Department of Shaanxi Province(Grant No.12JK0445)the Graduate Innovation Fund of Shaanxi University of Science and Technology(SUST-A04)
文摘Bil_xTbxFe03 thin films were prepared on Sn02 (fluorine doped tin oxide) substrates by a sol-gel method. The structural and electrical properties of the BiFe03 thin films were characterized and tested. The results indicated that the diffraction peak of the Tb-doped BiFe03 films was shifted towards right as the doping amounts were increased. The structure was transformed from the rhombohedral to tetragonal/orthorhombic phase. The Bio.sgTbo.11Fe03 thin film showed the well-developed P-E loops, which enhanced remnant polarization (Pr = 88.05 μC/cm2) at room temperature. The dielectric constant and dielectric loss of Bio.sgTbo.llFe03 thin film at 100 kHz were 185 and 0.018, respectively. Furthermore, the Bio.seTbo.llFe03 thin film showed a relatively low leakage current density of 2.07×10-5 A/cm2 at an applied electric field of 150 kV/cm. The X- ray photoelectron spectroscopy (XPS) spectra indicated that the presence of Fe2+ ions in the Bio.egTbo.11Fe03 thin film was less than that in the pure BiFe03.
基金This work was supported by grants from the National Natural Science Foundation of China(No.51272274,81672227,51372170)Shenzhen Peacock Program(No.110811003586331)Shenzhen Science and Technology Research funding(No.CXZZ 20150401152251209,JSGG20151030140325149,JSGG20150331154931068,CXZZ20140417113430716)and partially from Hong Kong General Research Fund.
文摘In osteoporosis scenario, tissue response to implants is greatly impaired by the deteriorated boneregeneration microenvironment. In the present study, a Mg-containing akermanite (Ak) ceramic wasemployed for the treatment of osteoporotic bone defect, based on the hypothesis that both beneficialions (e.g. Mg^2+ ect.) released by the implants and the weak alkaline microenvironment pH (μe-pH) itcreated may play distinct roles in recovering the abnormal bone regeneration by stimulating osteoblasticanabolic effects. The performance of Ak, b-tricalcium phosphate (β-TCP) and Hardystone (Har) in healinga 3 mm bone defect on the ovariectomized (OVX) osteoporotic rat model was evaluated. Our resultsindicated that, there's more new bone formed in Ak group than in β-TCP or Har group at week 9. Theinitial me-pHs of Ak were significantly higher than that of the β-TCP and Blank group, and this weakalkaline condition was maintained till at least 9 weeks post-surgery. Increased osteoblastic activity whichwas indicated by higher osteoid secretion was observed in Ak group at week 4 to week 9. An intermediatelayer which was rich in phosphorus minerals and bound directly to the new forming bone wasdeveloped on the surface of Ak. In a summary, our study demonstrates that Ak exhibits a superior boneregenerative performance under osteoporosis condition, and might be a promising candidate for thetreatment of osteoporotic bone defect and fracture.