The continuously growing importance of information storage,transmission,and authentication impose many new demands and challenges for modern nano-photonic materials and information storage technologies,both in securit...The continuously growing importance of information storage,transmission,and authentication impose many new demands and challenges for modern nano-photonic materials and information storage technologies,both in security and storage capacity.Recently,luminescent lanthanide-doped nanomaterials have drawn much attention in this field because of their photostability,multimodal/multicolor/narrowband emissions,and long luminescence lifetime.Here,we report a multimodal nanocomposite composed of lanthanide-doped upconverting nanoparticle and EuSe semiconductor,which was constructed by utilizing a cation exchange strategy.The nanocomposite can emit blue and white light under 365 and 394 nm excitation,respectively.Meanwhile,the nanocomposites show different colors under 980 nm laser excitation when the content of Tb3+ions is changed in the upconversion nanoparticles.Moreover,the time-gating technology is used to filter the upconversion emission of a long lifetime from Tb3+or Eu3+,and the possibilities for modulating the emission color of the nanocomposites are further expanded.Based on the advantage of multiple tunable luminescence,the nanocomposites are designed as optical modules to load optical information.This work enables multi-dimensional storage of information and provides new insights into the design and fabrication of next-generation storage materials.展开更多
Fuke (19.5°N, 109.1°E) meteor radar is the first radar of the low latitudes of China, which is used to detect the wind in the meso- sphere and lower thermosphere. In this paper, by using the wind data near t...Fuke (19.5°N, 109.1°E) meteor radar is the first radar of the low latitudes of China, which is used to detect the wind in the meso- sphere and lower thermosphere. In this paper, by using the wind data near three months (1 February-20 April, 2009), we first present the variation of the atmospheric diurnal tide, semidiurnal tide and mean wind in the height range 80-100 km over the low latitudes of China. The results from our analysis are summarized below. During spring months, there are quite strong tides in the mesopause region of Fuke. The diurnal tidal amplitude is significantly larger than the amplitude of semidiurnal tide, and the maximum amplitude (about 100 m/s) of diurnal tide appear in the meridional wind. The vertical phases of both diurnal tide and semidiurnal tide propagate downward. In addition, the observed tides are compared with the linear tide model (Global Scale Wave Model, GSWM02), and the results show that Fuke diurnal tide agrees well with the model, but there are many differences between Fuke semidiurnal tide and the results from model.展开更多
In order to achieve the lateral control of the intelligent vehicle, use the bi-cognitive model based on cloud model and cloud reasoning, solve the decision problem of the qualitative and quantitative of the lateral co...In order to achieve the lateral control of the intelligent vehicle, use the bi-cognitive model based on cloud model and cloud reasoning, solve the decision problem of the qualitative and quantitative of the lateral control of the intelligent vehicle. Obtaining a number of experiment data by driving a vehicle, classify the data according to the concept of data and fix the input and output variables of the cloud controller, design the control rules of the cloud controller of intelligent vehicle, and clouded and fix the parameter of cloud controller： expectation, entropy and hyper entropy. In order to verify the effectiveness of the cloud controller, joint simulation platform based on Matlab/Simulink/CarSim is established. Experimental analysis shows that： driver＇s lateral controller based on cloud model is able to achieve tracking of the desired angle, and achieve good control effect, it also verifies that a series of mental activities such as feeling, cognition, calculation, decision and so on are fuzzy and uncertain.展开更多
Central nervous system(CNS)injuries,including stroke,traumatic brain injury,and spinal cord injury,are leading causes of long-term disability.It is estimated that more than half of the survivors of severe unilateral i...Central nervous system(CNS)injuries,including stroke,traumatic brain injury,and spinal cord injury,are leading causes of long-term disability.It is estimated that more than half of the survivors of severe unilateral injury are unable to use the denervated limb.Previous studies have focused on neuroprotective interventions in the affected hemisphere to limit brain lesions and neurorepair measures to promote recovery.However,the ability to increase plasticity in the injured brain is restricted and difficult to improve.Therefore,over several decades,researchers have been prompted to enhance the compensation by the unaffected hemisphere.Animal experiments have revealed that regrowth of ipsilateral descending fibers from the unaffected hemisphere to denervated motor neurons plays a significant role in the restoration of motor function.In addition,several clinical treatments have been designed to restore ipsilateral motor control,including brain stimulation,nerve transfer surgery,and brain–computer interface systems.Here,we comprehensively review the neural mechanisms as well as translational applications of ipsilateral motor control upon rehabilitation after CNS injuries.展开更多
The deep removal of Al, Fe（Ⅱ/Ⅲ）, Ca, Zr, Ti and Si from scandium chloride solution was carried out by using 732-type strong acid cation exchange resin. The effects of pH value, contact time and complexing agents（...The deep removal of Al, Fe（Ⅱ/Ⅲ）, Ca, Zr, Ti and Si from scandium chloride solution was carried out by using 732-type strong acid cation exchange resin. The effects of pH value, contact time and complexing agents（EDTA） on the purification process are investigated. The results indicate that the 732-type resin have a good scandium selectivity and the adsorption order is Sc 〉 Fe（Ⅲ）〉Al 〉 Ca 〉 Zr 〉 Ti 〉 Si in the pH range of 1-3. The separation of Sc and Zr, Si, Ti can be directly carried out because the resin have a good adsorption effect on Sc, AI and Fe（Ⅲ） but poor adsorption effect on Zr, Si and Ti under the condition of pH = 2.5 and contact time 180 min. The Fe（Ⅱ）, Ca and Al are selectively adsorbed on the resin by adding reducing agent ascorbic acid and EDTA into the solution for reducing Fe（Ⅲ） to Fe（Ⅱ） and complexing Sc.By using two-step ion exchange adsorption separation method, the removal rates of Fe（Ⅲ）, Ti, Al, Ca, Zr and Si are 95.5%,99.8%,100%,98.2%,98.6% and 100%,respectively.展开更多
The synthetic microbial community is a synthetic microbial system co-cultured with multiple species, which has the characteristics of clear composition and strong controllability. Compared with a single colony, it can...The synthetic microbial community is a synthetic microbial system co-cultured with multiple species, which has the characteristics of clear composition and strong controllability. Compared with a single colony, it can achieve more complex functions and adapt to the changing environment more easily, so as to meet a wide range of needs. In this paper, the contents and concepts of microbial community and synthetic microbial community are briefly introduced, the principles that should be followed in the construction of microbial community are expounded, the methods and mathematical models used in the construction of synthetic microbial community are introduced, and the applications of synthetic microbial community in various fields are summarized. Finally, the challenges in the research of synthetic microbial communities are briefly described.展开更多
Background and Aims:FibroScan is used to determine liver stiffness and controlled attenuation parameter (referred to as CAP) scores in patients, including those with chronic hepatitis B (CHB). We used FibroScan to det...Background and Aims:FibroScan is used to determine liver stiffness and controlled attenuation parameter (referred to as CAP) scores in patients, including those with chronic hepatitis B (CHB). We used FibroScan to detect the incidence of fatty liver and fibrosis in CHB patients, and to assess the correla-tion of FibroScan measurements with blood chemistry tests. Methods: CHB patients enrolled in this study were divided independently for three separate analyses (of fibrosis, cirrho-sis, and fatty liver) based on FibroScan results. Basic infor-mation, blood chemistry test results, liver fibrosis parameters, and FibroScan results were collected. T-tests and Pearson's analyses were used to analyze the correlations between FibroScan liver stiffness measurement/CAP values and liver function, blood fat, uric acid metabolite, fibrosis, and hepatitis B virus load. Results:A total of 2266 CHB pa-tients were enrolled in the study and divided into three groups:non-significant and significant fibrosis;non-cirrhosis and early cirrhosis;and non-fatty and fatty liver. Spearman's statistical analyses showed that liver stiffness measurement or CAP values correlated with sex (r=0.137), age (r=0.119), glutamic-pyruvic transaminase (r=0.082), glutamic-oxalo-acetic transaminase (r=–0.172), gamma-glutamyltransfer-ase (r=0.225), albumin (r=0.150), globulin (r=–0.107), total bilirubin (r=–0.132), direct bilirubin (r=–0.145), white blood cell count (r=0.254), hemoglobin (r=0.205), platelets (r=0.206), total cholesterol (r=0.214), high density lipopro-tein (r=–0.243), low density lipoprotein (r=0.255), apolipo-protein B (r=0.217), hyaluronic acid (r=–0.069), laminin (r=–0.188), procollagen type IV (r=–0.067)and hepatitis B viral DNA load (r=–0.216). Conclusions: FibroScan is a non-invasive device that can detect the occurrence of fatty liver or liver fibrosis in CHB patients.展开更多
Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude ionosphere.Metallic sodium detected by l...Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude ionosphere.Metallic sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s atmosphere.This paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the southern.The low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in summer.However,maximal Na density over Brazil is greater than that over Hainan.Nocturnal variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before sunrise.Some variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain effect.We suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.展开更多
A novel glucose biosensor was constructed by immobilizing the glucose oxidase(GOD) on a hydroxyapatite(HAp)/Nafion composite film modified glassy carbon electrode(GCE) and applied to the highly selective and sensitive...A novel glucose biosensor was constructed by immobilizing the glucose oxidase(GOD) on a hydroxyapatite(HAp)/Nafion composite film modified glassy carbon electrode(GCE) and applied to the highly selective and sensitive determination of glucose.With the cooperation of HAp and Nafion,the composite film played an important role in enhancing the stability and sensitivity of the biosensor.The results demonstrate that the GOD adsorbed onto the HAp/Nafion composite film exhibits a pair of welldefined nearly reversible redox peaks and fine catalysis to the oxidation of glucose companied with the consumption of dissolved oxygen.On the basis of the decrease of the reduction current of dissolved oxygen at the applied potential of -0.80 V(vs.SCE) upon the addition of glucose,the concentration of glucose could be detected sensitively and selectively.The decreased reduction current was linear with the concentration of glucose in the range of 0.12―2.16 mM.The detection limit and sensitivity were 0.02 mM(S/N=3) and 6.75 mA·M-1,respectively.All the results demonstrate that HAp/Nafion composite film provides a novel and efficient platform for the immobilization of enzymes and realizes the direct electrochemistry.The composite materials should have potential applications in the fabrication of third-generation biosensors.展开更多
The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controver...The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and 展开更多
Along with the increasing number of vehicles, parking space becomes narrow gradually, safety parking puts forward higher requirements on the driver＇s driving technology. How to safely, quickly and accurately park the...Along with the increasing number of vehicles, parking space becomes narrow gradually, safety parking puts forward higher requirements on the driver＇s driving technology. How to safely, quickly and accurately park the vehiclo to parking space right？ This paper presents an automatic parking scheme based on trajectory planning, which analyzing the mechanical model oftbe vehicle, establishing vehicle steering model and parking model, coming to the conclusion that it is the turning radius is independent of the vehicle speed at low speed. The Matlab simulation environment verifies the correctness and effectiveness of the proposed algorithm for parking. A class of the automatic parking problem of intelligent vehicles is solved.展开更多
Identification of magnitude and orientation for spatially applied loading is highly desired in the fields of not only the machinery components but also human-machine interaction.Despite the fact that the 3-axis force ...Identification of magnitude and orientation for spatially applied loading is highly desired in the fields of not only the machinery components but also human-machine interaction.Despite the fact that the 3-axis force sensor with different structures has been proposed to measure the spatial force,there are still some common limitations including the multi-step manufacturing-assembly processes and complicated testing of decoupling calibration.Here,we propose a rapid fabrication strategy with low-cost to achieve high-precision 3-axis force sensors.The sensor is designed to compose of structural Maltese cross base and sensing units.It is directly fabricated within one step by a hybrid 3D printing technology combining deposition modeling(FDM)with direct-ink-writing(DIW).In particular,a machine learning(ML)model is used to convert the strain signal to the force components.Instead of a mount of calibration tests,this ML model is trained by sufficient simulation data based on programmed batch finite element modeling.This sensor is capable of continuously identifying a spatial force with varying magnitude and orientation,which successfully quantify the applied force of traditional Chinese medicine physiotherapy including Gua Sha and massage.This work provides insight for design and rapid fabrication of multi-axis force sensors,as well as potential applications.展开更多
A photocleavable low-molecular-weight hydrogelator (LMWG) was synthesized based on coumarin derivative.~1H NMR and UV spectroscopy study suggested that the gelator had good gelling ability, and the driving force for t...A photocleavable low-molecular-weight hydrogelator (LMWG) was synthesized based on coumarin derivative.~1H NMR and UV spectroscopy study suggested that the gelator had good gelling ability, and the driving force for the gelation were hydrogen bonding and π-π stacking. This molecular hydrogel exhibited satisfied photocleavage at C-N bond in 7-amino coumarin with the light irradiation (365 nm,77.5 mW/cm^2). The promising photo-triggered drug release of antineoplastics cytarabine hydrochloride has been obtained, due to the photocleavage motived gel-sol transition.展开更多
Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-t...Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-two-dimensional(quasi-2D)fluidized bed,including bubble equivalent diameter,bubble size distribution,average bubble density,bubble aspect ratio,bubble hold-up,bed expansion ratio,bubble radial position,and bubble velocity.The studies were performed by computational particle fluid dynamics(CPFD)numerical simulation and post-processed with digital image analysis(DIA)technique,at superficial gas velocities ranging from 2u_(mf) to 7u_(mf).The simulated results shown that the CPFD simulation combining with DIA technique post-processing could be used as a reliable method for simulating bubble dynamics properties in quasi-2D gas-solid fluidized beds.However,it seemed not desirable for the simulation of bubble motion near the air distributor at higher superficial gas velocity from the simulated average bubble density distribution.The superficial gas velocity significantly affected the bubble equivalent diameter and evolution,while it had little influence on bubble size distribution and bubble aspect ratio distribution for the same particles.Both time-averaged bubble hold-up and bed expansion ratio increased with the increase of superficial gas velocity.Two core-annular flow structures could be found in the fluidized bed for all cases.The average bubble rising velocity increased with the increasing bubble equivalent diameter.For bubble lateral movement,the smaller bubbles might be more susceptible,and superficial gas velocity had a little influence on the absolute lateral velocity of bubbles.The simulated results presented a valuable and novel approach for studying bubble dynamics properties.The comprehensive understanding of bubble dynamics behaviors in quasi-2D gas-solid fluidized beds would provide support in the design,operation,and optimization of gas-solid fluidized bed reactors.展开更多
In today’s highly competitive retail industry,offline stores face increasing pressure on profitability.They hope to improve their ability in shelf management with the help of big data technology.For this,on-shelf ava...In today’s highly competitive retail industry,offline stores face increasing pressure on profitability.They hope to improve their ability in shelf management with the help of big data technology.For this,on-shelf availability is an essential indicator of shelf data management and closely relates to customer purchase behavior.RFM(recency,frequency,andmonetary)patternmining is a powerful tool to evaluate the value of customer behavior.However,the existing RFM patternmining algorithms do not consider the quarterly nature of goods,resulting in unreasonable shelf availability and difficulty in profit-making.To solve this problem,we propose a quarterly RFM mining algorithmfor On-shelf products named OS-RFM.Our algorithmmines the high recency,high frequency,and high monetary patterns and considers the period of the on-shelf goods in quarterly units.We conducted experiments using two real datasets for numerical and graphical analysis to prove the algorithm’s effectiveness.Compared with the state-of-the-art RFM mining algorithm,our algorithm can identify more patterns and performs well in terms of precision,recall,and F1-score,with the recall rate nearing 100%.Also,the novel algorithm operates with significantly shorter running times and more stable memory usage than existing mining algorithms.Additionally,we analyze the sales trends of products in different quarters and seasonal variations.The analysis assists businesses in maintaining reasonable on-shelf availability and achieving greater profitability.展开更多
Self-localization and orientation estimation are the essential capabilities for mobile robot navigation.In this article,a robust and real-time visual-inertial-GNSS(Global Navigation Satellite System)tightly coupled po...Self-localization and orientation estimation are the essential capabilities for mobile robot navigation.In this article,a robust and real-time visual-inertial-GNSS(Global Navigation Satellite System)tightly coupled pose estimation(RRVPE)method for aerial robot navigation is presented.The aerial robot carries a front-facing stereo camera for self-localization and an RGB-D camera to generate 3D voxel map.Ulteriorly,a GNSS receiver is used to continuously provide pseudorange,Doppler frequency shift and universal time coordinated(UTC)pulse signals to the pose estimator.The proposed system leverages the Kanade Lucas algorithm to track Shi-Tomasi features in each video frame,and the local factor graph solution process is bounded in a circumscribed container,which can immensely abandon the computational complexity in nonlinear optimization procedure.The proposed robot pose estimator can achieve camera-rate(30 Hz)performance on the aerial robot companion computer.We thoroughly experimented the RRVPE system in both simulated and practical circumstances,and the results demonstrate dramatic advantages over the state-of-the-art robot pose estimators.展开更多
Organ damage or failure arising from injury,disease,and aging poses challenges due to the body’s limited regenerative capabilities.Organ transplantation presents the issues of donor shortages and immune rejection ris...Organ damage or failure arising from injury,disease,and aging poses challenges due to the body’s limited regenerative capabilities.Organ transplantation presents the issues of donor shortages and immune rejection risks,necessitating innovative solutions.The three-dimensional(3D)bioprinting of organs on demand offers promise in tissue engineering and regenerative medicine.In this review,we explore the state-of-the-art bioprinting technologies,with a focus on bioink and cell type selections.We follow with discussions on advances in the bioprinting of solid organs,such as the heart,liver,kidney,and pancreas,highlighting the importance of vascularization and cell integration.Finally,we provide insights into key challenges and future directions in the context of the clinical translation of bioprinted organs and their large-scale production.展开更多
The widespread use of feed additives in intensive and large-scale pig farming has resulted in high levels of heavy metals in pig manure.The long-term application of organic fertilizers containing high levels of heavy ...The widespread use of feed additives in intensive and large-scale pig farming has resulted in high levels of heavy metals in pig manure.The long-term application of organic fertilizers containing high levels of heavy metals leads to the accumulation of heavy metals in the soil,which not only causes heavy metal pollution in the soil,and also affect food safety and endanger human health.Composting is an economical and effective technical measures to achieve environmentally-sustainable treatment of pig manure and is a practical method to reduce the problem of heavy metals and to improve the resource value of pig manure.The composting process is accompanied by high temperatures and the production and emission of gases,and also lead to changes in the nitrogen content of the compost and provide opportunity for heavy metal passivation additives.This paper summarizes the forms and types of heavy metals present in pig manure and reviews the progress of research as well as the techniques and problems of in the composting process,and provides recommendations for research on heavy metal passivation and nitrogen retention in pig manure composting.展开更多
The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids(BR)and sterols,as well as plant development.OsFK1,a member of the sterol biosynthesis pathway located in the endoplasmic reticulum(ER),e...The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids(BR)and sterols,as well as plant development.OsFK1,a member of the sterol biosynthesis pathway located in the endoplasmic reticulum(ER),encodes C-14 sterol reductase.However,there is little research on the function of C-14 sterol reductase in rice.Compared with the wild type,an osfk1 mutant showed dwarf phenotype and premature aging in the second leaf during the trefoil stage,and abnormal development of leaf veins during the tillering stage.The osfk1 mutant showed signs of aberrant PCD,as evidenced by TUNEL staining.This suggested that high ROS buildup caused DNA damage and ROS-mediated cell death in the mutant.The osfk1 mutant also showed decreased chlorophyll content and aberrant chloroplast structure.Sequencing of the osfk1 mutant allele revealed a non-synonymous G to A mutation in the final intron,leading to early termination.Here,we identified the OsFK1 allele,cloned it by Mutmap sequencing,and verified it by complementation.HPLC-MS/MS assays demonstrated that the osfk1 mutation caused lower phytosterol levels.These findings showed that the OsFK1 allele encoding C-14 sterol reductase is involved in phytosterol biosynthesis and mediates normal development of rice plants.展开更多
基金The research was funded by the National Natural Science Foundation of China(Grant No.51872183)"Shuguang Program"supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.19SG38).
文摘The continuously growing importance of information storage,transmission,and authentication impose many new demands and challenges for modern nano-photonic materials and information storage technologies,both in security and storage capacity.Recently,luminescent lanthanide-doped nanomaterials have drawn much attention in this field because of their photostability,multimodal/multicolor/narrowband emissions,and long luminescence lifetime.Here,we report a multimodal nanocomposite composed of lanthanide-doped upconverting nanoparticle and EuSe semiconductor,which was constructed by utilizing a cation exchange strategy.The nanocomposite can emit blue and white light under 365 and 394 nm excitation,respectively.Meanwhile,the nanocomposites show different colors under 980 nm laser excitation when the content of Tb3+ions is changed in the upconversion nanoparticles.Moreover,the time-gating technology is used to filter the upconversion emission of a long lifetime from Tb3+or Eu3+,and the possibilities for modulating the emission color of the nanocomposites are further expanded.Based on the advantage of multiple tunable luminescence,the nanocomposites are designed as optical modules to load optical information.This work enables multi-dimensional storage of information and provides new insights into the design and fabrication of next-generation storage materials.
基金supported by the National Natural Science Foundation of China (Grant Nos. 40621003 40804037 and 40621003)+1 种基金National Basic Research Program of China (Grant No. 2006CB806306) Specialized Research Fund for State Key Laboratories
文摘Fuke (19.5°N, 109.1°E) meteor radar is the first radar of the low latitudes of China, which is used to detect the wind in the meso- sphere and lower thermosphere. In this paper, by using the wind data near three months (1 February-20 April, 2009), we first present the variation of the atmospheric diurnal tide, semidiurnal tide and mean wind in the height range 80-100 km over the low latitudes of China. The results from our analysis are summarized below. During spring months, there are quite strong tides in the mesopause region of Fuke. The diurnal tidal amplitude is significantly larger than the amplitude of semidiurnal tide, and the maximum amplitude (about 100 m/s) of diurnal tide appear in the meridional wind. The vertical phases of both diurnal tide and semidiurnal tide propagate downward. In addition, the observed tides are compared with the linear tide model (Global Scale Wave Model, GSWM02), and the results show that Fuke diurnal tide agrees well with the model, but there are many differences between Fuke semidiurnal tide and the results from model.
基金supported by the National Natural Science Foundation of China (61035004,61273213,61300006,61305055,90920305,61203366,91420202,61571045,61372148)the National Hi-Tech Research and Development Program of China (2015AA015401)+2 种基金the National Basic Research Program of China (2016YFB0100906,2016YFB100903)the Junior Fellowships for Advanced Innovation Think-Tank Program of China Association for Science and Technology (DXB-ZKQN-2017-035)the Beijing Municipal Science and Technology Commission Special Major (D171100005017002)
文摘In order to achieve the lateral control of the intelligent vehicle, use the bi-cognitive model based on cloud model and cloud reasoning, solve the decision problem of the qualitative and quantitative of the lateral control of the intelligent vehicle. Obtaining a number of experiment data by driving a vehicle, classify the data according to the concept of data and fix the input and output variables of the cloud controller, design the control rules of the cloud controller of intelligent vehicle, and clouded and fix the parameter of cloud controller： expectation, entropy and hyper entropy. In order to verify the effectiveness of the cloud controller, joint simulation platform based on Matlab/Simulink/CarSim is established. Experimental analysis shows that： driver＇s lateral controller based on cloud model is able to achieve tracking of the desired angle, and achieve good control effect, it also verifies that a series of mental activities such as feeling, cognition, calculation, decision and so on are fuzzy and uncertain.
基金This review was supported by the National Natural Science Foundation of China(81902296,82071406,82021002,92168105)Shanghai Municipal Science and Technology Major Project(2018SHZDZX05)Shanghai Natural Science Foundation[20XD1420700,22ZR1479000].
文摘Central nervous system(CNS)injuries,including stroke,traumatic brain injury,and spinal cord injury,are leading causes of long-term disability.It is estimated that more than half of the survivors of severe unilateral injury are unable to use the denervated limb.Previous studies have focused on neuroprotective interventions in the affected hemisphere to limit brain lesions and neurorepair measures to promote recovery.However,the ability to increase plasticity in the injured brain is restricted and difficult to improve.Therefore,over several decades,researchers have been prompted to enhance the compensation by the unaffected hemisphere.Animal experiments have revealed that regrowth of ipsilateral descending fibers from the unaffected hemisphere to denervated motor neurons plays a significant role in the restoration of motor function.In addition,several clinical treatments have been designed to restore ipsilateral motor control,including brain stimulation,nerve transfer surgery,and brain–computer interface systems.Here,we comprehensively review the neural mechanisms as well as translational applications of ipsilateral motor control upon rehabilitation after CNS injuries.
基金Project supported by the National Science and Technology Support Program(2015BAB19B03)
文摘The deep removal of Al, Fe（Ⅱ/Ⅲ）, Ca, Zr, Ti and Si from scandium chloride solution was carried out by using 732-type strong acid cation exchange resin. The effects of pH value, contact time and complexing agents（EDTA） on the purification process are investigated. The results indicate that the 732-type resin have a good scandium selectivity and the adsorption order is Sc 〉 Fe（Ⅲ）〉Al 〉 Ca 〉 Zr 〉 Ti 〉 Si in the pH range of 1-3. The separation of Sc and Zr, Si, Ti can be directly carried out because the resin have a good adsorption effect on Sc, AI and Fe（Ⅲ） but poor adsorption effect on Zr, Si and Ti under the condition of pH = 2.5 and contact time 180 min. The Fe（Ⅱ）, Ca and Al are selectively adsorbed on the resin by adding reducing agent ascorbic acid and EDTA into the solution for reducing Fe（Ⅲ） to Fe（Ⅱ） and complexing Sc.By using two-step ion exchange adsorption separation method, the removal rates of Fe（Ⅲ）, Ti, Al, Ca, Zr and Si are 95.5%,99.8%,100%,98.2%,98.6% and 100%,respectively.
文摘The synthetic microbial community is a synthetic microbial system co-cultured with multiple species, which has the characteristics of clear composition and strong controllability. Compared with a single colony, it can achieve more complex functions and adapt to the changing environment more easily, so as to meet a wide range of needs. In this paper, the contents and concepts of microbial community and synthetic microbial community are briefly introduced, the principles that should be followed in the construction of microbial community are expounded, the methods and mathematical models used in the construction of synthetic microbial community are introduced, and the applications of synthetic microbial community in various fields are summarized. Finally, the challenges in the research of synthetic microbial communities are briefly described.
基金Medical Scientific Research Foundation of Guangdong Prov-ince of China (A2016450 and A2013695)
文摘Background and Aims:FibroScan is used to determine liver stiffness and controlled attenuation parameter (referred to as CAP) scores in patients, including those with chronic hepatitis B (CHB). We used FibroScan to detect the incidence of fatty liver and fibrosis in CHB patients, and to assess the correla-tion of FibroScan measurements with blood chemistry tests. Methods: CHB patients enrolled in this study were divided independently for three separate analyses (of fibrosis, cirrho-sis, and fatty liver) based on FibroScan results. Basic infor-mation, blood chemistry test results, liver fibrosis parameters, and FibroScan results were collected. T-tests and Pearson's analyses were used to analyze the correlations between FibroScan liver stiffness measurement/CAP values and liver function, blood fat, uric acid metabolite, fibrosis, and hepatitis B virus load. Results:A total of 2266 CHB pa-tients were enrolled in the study and divided into three groups:non-significant and significant fibrosis;non-cirrhosis and early cirrhosis;and non-fatty and fatty liver. Spearman's statistical analyses showed that liver stiffness measurement or CAP values correlated with sex (r=0.137), age (r=0.119), glutamic-pyruvic transaminase (r=0.082), glutamic-oxalo-acetic transaminase (r=–0.172), gamma-glutamyltransfer-ase (r=0.225), albumin (r=0.150), globulin (r=–0.107), total bilirubin (r=–0.132), direct bilirubin (r=–0.145), white blood cell count (r=0.254), hemoglobin (r=0.205), platelets (r=0.206), total cholesterol (r=0.214), high density lipopro-tein (r=–0.243), low density lipoprotein (r=0.255), apolipo-protein B (r=0.217), hyaluronic acid (r=–0.069), laminin (r=–0.188), procollagen type IV (r=–0.067)and hepatitis B viral DNA load (r=–0.216). Conclusions: FibroScan is a non-invasive device that can detect the occurrence of fatty liver or liver fibrosis in CHB patients.
基金supported by the NSFC(42374204,42004143,42364012)the Project of Stable Support for Youth Team in Basic Research Field,Chinese Academy of Sciences(Grant No.YSBR-018)+1 种基金the Scientific Projects of Hainan Province(KJRC2023C05,ZDYF2021GXJS040)the Innovational Fund for Scientific and Technological Personnel of Hainan Province,the Chinese Meridian Project,and Pandeng Program of National Space Science Center,Chinese Academy of Sciences.
文摘Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude ionosphere.Metallic sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s atmosphere.This paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the southern.The low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in summer.However,maximal Na density over Brazil is greater than that over Hainan.Nocturnal variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before sunrise.Some variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain effect.We suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 20475024 & 2077503)Shandong Tai-Shan Scholar Research Fund
文摘A novel glucose biosensor was constructed by immobilizing the glucose oxidase(GOD) on a hydroxyapatite(HAp)/Nafion composite film modified glassy carbon electrode(GCE) and applied to the highly selective and sensitive determination of glucose.With the cooperation of HAp and Nafion,the composite film played an important role in enhancing the stability and sensitivity of the biosensor.The results demonstrate that the GOD adsorbed onto the HAp/Nafion composite film exhibits a pair of welldefined nearly reversible redox peaks and fine catalysis to the oxidation of glucose companied with the consumption of dissolved oxygen.On the basis of the decrease of the reduction current of dissolved oxygen at the applied potential of -0.80 V(vs.SCE) upon the addition of glucose,the concentration of glucose could be detected sensitively and selectively.The decreased reduction current was linear with the concentration of glucose in the range of 0.12―2.16 mM.The detection limit and sensitivity were 0.02 mM(S/N=3) and 6.75 mA·M-1,respectively.All the results demonstrate that HAp/Nafion composite film provides a novel and efficient platform for the immobilization of enzymes and realizes the direct electrochemistry.The composite materials should have potential applications in the fabrication of third-generation biosensors.
基金financially supported by the National Key Research and Development Program of China(Grant No.2021YFC2901903)the Geological Comprehensive Research Project of China’s Metallurgical Geology Bureau(Grant No.[2022]CMGBDZYJ005),the National Natural Science Foundation of China(Grant No.42002097)the Geological Investigation Project(Grant Nos.DD20230031,DD20221690,DD20230049,DD20230337).
文摘The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and
基金supported by the National Natural Science Foundation of China (61035004, 61273213, 61300006, 61305055, 90920305, 61203366, 91420202)the National Hi-Tech Research and Development Program of China (2015AA015401)+3 种基金the National Basic Research Program of China (2016YFB0100906, 2016YFB0100903)the Junior Fellowships for Advanced Innovation Think-Tank Program of China Association for Science and Technology (DXB-ZKQN-2017-035)the Project Funded by China Postdoctoral Science Foundationthe Beijing Municipal Science and Technology Commission Special Major (D171100005017002)
文摘Along with the increasing number of vehicles, parking space becomes narrow gradually, safety parking puts forward higher requirements on the driver＇s driving technology. How to safely, quickly and accurately park the vehiclo to parking space right？ This paper presents an automatic parking scheme based on trajectory planning, which analyzing the mechanical model oftbe vehicle, establishing vehicle steering model and parking model, coming to the conclusion that it is the turning radius is independent of the vehicle speed at low speed. The Matlab simulation environment verifies the correctness and effectiveness of the proposed algorithm for parking. A class of the automatic parking problem of intelligent vehicles is solved.
基金supported by the National Natural Science Foundation of China [12372078]Sixth Phase of Jiangsu Province"333 High Level Talent Training Project"Second Level Talents State Key Laboratory of Mechanics and Control of Mechanical Structures (Nanjing University of Aeronautics and astronautics [MCMS-E-0422G04].
文摘Identification of magnitude and orientation for spatially applied loading is highly desired in the fields of not only the machinery components but also human-machine interaction.Despite the fact that the 3-axis force sensor with different structures has been proposed to measure the spatial force,there are still some common limitations including the multi-step manufacturing-assembly processes and complicated testing of decoupling calibration.Here,we propose a rapid fabrication strategy with low-cost to achieve high-precision 3-axis force sensors.The sensor is designed to compose of structural Maltese cross base and sensing units.It is directly fabricated within one step by a hybrid 3D printing technology combining deposition modeling(FDM)with direct-ink-writing(DIW).In particular,a machine learning(ML)model is used to convert the strain signal to the force components.Instead of a mount of calibration tests,this ML model is trained by sufficient simulation data based on programmed batch finite element modeling.This sensor is capable of continuously identifying a spatial force with varying magnitude and orientation,which successfully quantify the applied force of traditional Chinese medicine physiotherapy including Gua Sha and massage.This work provides insight for design and rapid fabrication of multi-axis force sensors,as well as potential applications.
基金financial support from the National Natural Science Foundation of China (Nos. 21672164, 21372177)
文摘A photocleavable low-molecular-weight hydrogelator (LMWG) was synthesized based on coumarin derivative.~1H NMR and UV spectroscopy study suggested that the gelator had good gelling ability, and the driving force for the gelation were hydrogen bonding and π-π stacking. This molecular hydrogel exhibited satisfied photocleavage at C-N bond in 7-amino coumarin with the light irradiation (365 nm,77.5 mW/cm^2). The promising photo-triggered drug release of antineoplastics cytarabine hydrochloride has been obtained, due to the photocleavage motived gel-sol transition.
基金the financial support provided by National Key R&D Project of China(grant No.2020YFB0606303)the technical supports received from Sam Clark in CPFD Software,LLC of USA,and from Hi-Key Technology Incorporated of China.
文摘Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-two-dimensional(quasi-2D)fluidized bed,including bubble equivalent diameter,bubble size distribution,average bubble density,bubble aspect ratio,bubble hold-up,bed expansion ratio,bubble radial position,and bubble velocity.The studies were performed by computational particle fluid dynamics(CPFD)numerical simulation and post-processed with digital image analysis(DIA)technique,at superficial gas velocities ranging from 2u_(mf) to 7u_(mf).The simulated results shown that the CPFD simulation combining with DIA technique post-processing could be used as a reliable method for simulating bubble dynamics properties in quasi-2D gas-solid fluidized beds.However,it seemed not desirable for the simulation of bubble motion near the air distributor at higher superficial gas velocity from the simulated average bubble density distribution.The superficial gas velocity significantly affected the bubble equivalent diameter and evolution,while it had little influence on bubble size distribution and bubble aspect ratio distribution for the same particles.Both time-averaged bubble hold-up and bed expansion ratio increased with the increase of superficial gas velocity.Two core-annular flow structures could be found in the fluidized bed for all cases.The average bubble rising velocity increased with the increasing bubble equivalent diameter.For bubble lateral movement,the smaller bubbles might be more susceptible,and superficial gas velocity had a little influence on the absolute lateral velocity of bubbles.The simulated results presented a valuable and novel approach for studying bubble dynamics properties.The comprehensive understanding of bubble dynamics behaviors in quasi-2D gas-solid fluidized beds would provide support in the design,operation,and optimization of gas-solid fluidized bed reactors.
基金partially supported by the Foundation of State Key Laboratory of Public Big Data(No.PBD2022-01).
文摘In today’s highly competitive retail industry,offline stores face increasing pressure on profitability.They hope to improve their ability in shelf management with the help of big data technology.For this,on-shelf availability is an essential indicator of shelf data management and closely relates to customer purchase behavior.RFM(recency,frequency,andmonetary)patternmining is a powerful tool to evaluate the value of customer behavior.However,the existing RFM patternmining algorithms do not consider the quarterly nature of goods,resulting in unreasonable shelf availability and difficulty in profit-making.To solve this problem,we propose a quarterly RFM mining algorithmfor On-shelf products named OS-RFM.Our algorithmmines the high recency,high frequency,and high monetary patterns and considers the period of the on-shelf goods in quarterly units.We conducted experiments using two real datasets for numerical and graphical analysis to prove the algorithm’s effectiveness.Compared with the state-of-the-art RFM mining algorithm,our algorithm can identify more patterns and performs well in terms of precision,recall,and F1-score,with the recall rate nearing 100%.Also,the novel algorithm operates with significantly shorter running times and more stable memory usage than existing mining algorithms.Additionally,we analyze the sales trends of products in different quarters and seasonal variations.The analysis assists businesses in maintaining reasonable on-shelf availability and achieving greater profitability.
基金Supported by the Guizhou Provincial Science and Technology Projects([2020]2Y044)the Science and Technology Projects of China Southern Power Grid Co.Ltd.(066600KK52170074)the National Natural Science Foundation of China(61473144)。
文摘Self-localization and orientation estimation are the essential capabilities for mobile robot navigation.In this article,a robust and real-time visual-inertial-GNSS(Global Navigation Satellite System)tightly coupled pose estimation(RRVPE)method for aerial robot navigation is presented.The aerial robot carries a front-facing stereo camera for self-localization and an RGB-D camera to generate 3D voxel map.Ulteriorly,a GNSS receiver is used to continuously provide pseudorange,Doppler frequency shift and universal time coordinated(UTC)pulse signals to the pose estimator.The proposed system leverages the Kanade Lucas algorithm to track Shi-Tomasi features in each video frame,and the local factor graph solution process is bounded in a circumscribed container,which can immensely abandon the computational complexity in nonlinear optimization procedure.The proposed robot pose estimator can achieve camera-rate(30 Hz)performance on the aerial robot companion computer.We thoroughly experimented the RRVPE system in both simulated and practical circumstances,and the results demonstrate dramatic advantages over the state-of-the-art robot pose estimators.
基金supported by the National Natural Science Foundation of China(82372403)the Shenzhen Science and Technology Program(ZDSYS20220606100606013)+5 种基金the Shenzhen Institute of Synthetic Biology Scientific Research Program(DWKF20190010 and JCHZ20200005)the Shenzhen Science and Technology Major Project(KJZD20230923114302006)the National Institute of Dental and Craniofacial Research Award(R01DE028614)the National Institute of Biomedical Imaging and Bioengineering Award(R01EB034566)the National Institute of Allergy and the Infectious Diseases Award(U19AI142733)the 2236 CoCirculation2 of TUBITAK award(121C359).
文摘Organ damage or failure arising from injury,disease,and aging poses challenges due to the body’s limited regenerative capabilities.Organ transplantation presents the issues of donor shortages and immune rejection risks,necessitating innovative solutions.The three-dimensional(3D)bioprinting of organs on demand offers promise in tissue engineering and regenerative medicine.In this review,we explore the state-of-the-art bioprinting technologies,with a focus on bioink and cell type selections.We follow with discussions on advances in the bioprinting of solid organs,such as the heart,liver,kidney,and pancreas,highlighting the importance of vascularization and cell integration.Finally,we provide insights into key challenges and future directions in the context of the clinical translation of bioprinted organs and their large-scale production.
基金supported by the National Key Research and Development Program of China(2018YFE0127000)Key R&D Program of Shaanxi Province(2022ZDLNY02-09)+1 种基金China Agriculture Research System(CARS-23-C-05)Postdoctoral Foundation of the Shaanxi Province(2018BSHEDZZ20)
文摘The widespread use of feed additives in intensive and large-scale pig farming has resulted in high levels of heavy metals in pig manure.The long-term application of organic fertilizers containing high levels of heavy metals leads to the accumulation of heavy metals in the soil,which not only causes heavy metal pollution in the soil,and also affect food safety and endanger human health.Composting is an economical and effective technical measures to achieve environmentally-sustainable treatment of pig manure and is a practical method to reduce the problem of heavy metals and to improve the resource value of pig manure.The composting process is accompanied by high temperatures and the production and emission of gases,and also lead to changes in the nitrogen content of the compost and provide opportunity for heavy metal passivation additives.This paper summarizes the forms and types of heavy metals present in pig manure and reviews the progress of research as well as the techniques and problems of in the composting process,and provides recommendations for research on heavy metal passivation and nitrogen retention in pig manure composting.
基金supported by the National Natural Science Foundation of China(32001491,32360493)Natural Science Foundation of Sichuan Province(2022NSFSC0153,2022NSFSC1754,2023NSFSC1170)the Key Research and Development Program of Sichuan Province(2021YFYZ0016).
文摘The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids(BR)and sterols,as well as plant development.OsFK1,a member of the sterol biosynthesis pathway located in the endoplasmic reticulum(ER),encodes C-14 sterol reductase.However,there is little research on the function of C-14 sterol reductase in rice.Compared with the wild type,an osfk1 mutant showed dwarf phenotype and premature aging in the second leaf during the trefoil stage,and abnormal development of leaf veins during the tillering stage.The osfk1 mutant showed signs of aberrant PCD,as evidenced by TUNEL staining.This suggested that high ROS buildup caused DNA damage and ROS-mediated cell death in the mutant.The osfk1 mutant also showed decreased chlorophyll content and aberrant chloroplast structure.Sequencing of the osfk1 mutant allele revealed a non-synonymous G to A mutation in the final intron,leading to early termination.Here,we identified the OsFK1 allele,cloned it by Mutmap sequencing,and verified it by complementation.HPLC-MS/MS assays demonstrated that the osfk1 mutation caused lower phytosterol levels.These findings showed that the OsFK1 allele encoding C-14 sterol reductase is involved in phytosterol biosynthesis and mediates normal development of rice plants.
