The capture zones of the continuous and pulsed guidance laws in the pursuit-evasion game are analytically discussed in this paper to provide deep insights into the capturability distinction between the continuous guid...The capture zones of the continuous and pulsed guidance laws in the pursuit-evasion game are analytically discussed in this paper to provide deep insights into the capturability distinction between the continuous guidance law and the pulsed guidance law.Specifically,first,in the pursuit-evasion game,various capture cases are defined regarding the Zero-Effort Miss distance(ZEM)to facilitate the capturability analysis.Then,for both the evader and the pursuer,the Linear-Quadratic Differential Game(LQDG)guidance laws concerning the continuous acceleration and the pulsed acceleration are converted into a unified form.In each capture case,the optimal solution existence conditions are derived,and the corresponding capture zones are formulated.The discussion on the capture zones shows that if the optimal solution exists,the distinction between the pulsed guidance law and the continuous guidance law can be neglected under small guidance effort weight.However,the capture zone of the continuous guidance law is larger than that of the pulsed guidance law with large pursuer guidance effort weight,but smaller with large evader guidance effort weight.Finally,various simulations are conducted to illustrate the distinction of the continuous and pulsed guidance laws,as well as the impact of the acceleration ratio and the time constant ratio on the capturability.展开更多
Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are cruci...Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.展开更多
In permanent magnet synchronous machine(PMSM) drives, temperature information is critical to achieve reliable and high-performance control. The popular model-based estimation methods are based on extracting temperatur...In permanent magnet synchronous machine(PMSM) drives, temperature information is critical to achieve reliable and high-performance control. The popular model-based estimation methods are based on extracting temperature dependent terms from the voltages using the machine model. The estimation accuracy under low speed or load can be greatly affected by the model uncertainty and noise due to low signal-tonoise ratio. This paper presents a high frequency(HF) position offset injection-based winding and permanent magnet(PM) temperature decoupled estimation approach for PMSMs to achieve accurate and robust temperature estimation among a wide speed range especially under low-speed conditions. In the proposed approach, a small HF position offset is injected into the machine to construct a decoupled winding and PM temperature estimation model, in which the winding and PM temperatures are independently estimated from HF excitations. The temperature estimation is independent from the fundamental model and parameter variation, and it achieves high signal-tonoise ratio under low-speed conditions. Moreover, the temperature estimation is also not affected by magnetic saturation and inverter distortion, which can improve the accuracy and robustness of temperature estimation. The proposed approach is validated with experiments and comparisons on a laboratory machine under various operating conditions.展开更多
A mode-pairing quantum key distribution based on heralded pair-coherent source with passive decoy-states is proposed,named HPCS-PDS-MP-QKD protocol,where the light sources at Alice and Bob sides are changed to heralde...A mode-pairing quantum key distribution based on heralded pair-coherent source with passive decoy-states is proposed,named HPCS-PDS-MP-QKD protocol,where the light sources at Alice and Bob sides are changed to heralded pair-coherent sources,and devices designed to implement passive decoy states are included at the transmitter sides to generate the decoy state pulses in the decoy-state window passively.With the defined efficient events and the designed pairing strategy,the key bits and bases can be obtained by data post-processing.Numerical simulation results verify the feasibility of the proposed protocol.The results show that the proposed protocol can exceed PLOB when the pairing interval setting is greater than 10^(3),and the transmission distance exceeds 200 km.When the key transmission distance reaches 300 km and the maximum pairing interval is equivalent to 1,its performance is improved by nearly 1.8 times compared to the original MP-QKD protocol with a weak coherent source(WCS-MP-QKD),and by 6.8 times higher than that of WCS-MPQKD with passive decoy states(WCS-PDS-MP-QKD).Meanwhile,the key transmission distance can reach 480 km,and surpasses the WCS-PDS-MP-QKD protocol by nearly 40 km.When the total pulse length is greater than 10^(11),the key generation rate is almost equal to that of infinite pulses.It is a promising QKD protocol that breaks the PLOB bound without requiring phase tracking and locking,has a longer transmission distance and a higher key generation rate,and eliminates the potential of side channel attack.展开更多
For permanent magnet synchronous machines(PMSMs),accurate inductance is critical for control design and condition monitoring.Owing to magnetic saturation,existing methods require nonlinear saturation model and measure...For permanent magnet synchronous machines(PMSMs),accurate inductance is critical for control design and condition monitoring.Owing to magnetic saturation,existing methods require nonlinear saturation model and measurements from multiple load/current conditions,and the estimation is relying on the accuracy of saturation model and other machine parameters in the model.Speed harmonic produced by harmonic currents is inductance-dependent,and thus this paper explores the use of magnitude and phase angle of the speed harmonic for accurate inductance estimation.Two estimation models are built based on either the magnitude or phase angle,and the inductances can be from d-axis voltage and the magnitude or phase angle,in which the filter influence in harmonic extraction is considered to ensure the estimation performance.The inductances can be estimated from the measurements under one load condition,which is free of saturation model.Moreover,the inductance estimation is robust to the change of other machine parameters.The proposed approach can effectively improve estimation accuracy especially under the condition with low current magnitude.Experiments and comparisons are conducted on a test PMSM to validate the proposed approach.展开更多
With the recent upsurge of studies in the field of microbiology,we have learned more about the complexity of the gastrointestinal microecosystem.More than 30 genera and 1000 species of gastrointestinal microflora have...With the recent upsurge of studies in the field of microbiology,we have learned more about the complexity of the gastrointestinal microecosystem.More than 30 genera and 1000 species of gastrointestinal microflora have been found.The structure of the normal microflora is relatively stable,and is in an interdependent and restricted dynamic equilibrium with the body.In recent years,studies have shown that there is a potential relationship between gastrointestinal microflora imbalance and gastric cancer(GC)and precancerous lesions.So,restoring the balance of gastrointestinal microflora is of great significance.Moreover,intervention in gastric premalignant condition(GPC),also known as precancerous lesion of gastric cancer(PLGC),has been the focus of current clinical studies.The holistic view of traditional Chinese medicine(TCM)is consistent with the microecology concept,and oral TCM can play a two-way regulatory role directly with the microflora in the digestive tract,restoring the homeostasis of gastrointestinal microflora to prevent canceration.However,large gaps in knowledge remain to be addressed.This review aims to provide new ideas and a reference for clinical practice.展开更多
Vascular endothelial growth factor(VEGF)is the main regulator of physiological angiogenesis during embryonic development,bone growth,and reproductive function,and it also participates in a series of pathological chang...Vascular endothelial growth factor(VEGF)is the main regulator of physiological angiogenesis during embryonic development,bone growth,and reproductive function,and it also participates in a series of pathological changes.Traditional Chinese medicine(TCM),with a history of more than 2000 years,has been widely used in clinical practice,while the exploration of its mechanisms has only begun.This review summarizes the research of recent years on the influence of TCM on VEGF.It is found that many Chinese medicines and recipes have a regulatory effect on VEGF,indicating that Chinese medicine has broad prospects as a complementary and alternative therapy,providing new treatment ideas for clinical applications and the theoretical basis for research on the mechanisms of TCM.展开更多
This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is math...This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is mathematically transforming the machine model to a virtual frame with a position-offset. The virtual frame temperature estimation model is derived to calculate the permanent magnet temperature(PMT) directly from the measurements with computation efficiency. The estimation model involves a combined inductance term, which can simplify the establishment of saturation compensation model with less measurements. Moreover, resistance and inverter distorted terms are cancelled in the estimation model, which can improve the robustness to the winding temperature rise and inverter distortion. The proposed approach can achieve simplified computation in temperature estimation and reduced memory usage in saturation compensation. While existing model-based approaches could be affected by either the need of resistance and inverter information or complex saturation compensation. Experiments are conducted on the test machine to verify the proposed approach under various operating conditions.展开更多
A sensitive and selective method was developed for the separation and characterization of related substances(RSs) in EVT-401 by hyphenated LC–MS techniques. Complete separation of the RSs was achieved with an Inertsi...A sensitive and selective method was developed for the separation and characterization of related substances(RSs) in EVT-401 by hyphenated LC–MS techniques. Complete separation of the RSs was achieved with an Inertsil ODS-SP column(250 mm×4.6 mm, 5 μm) by linear gradient elution using a mobile phase consisting of 0.2% formic acid solution, methanol and acetonitrile. EVT-401 was found to be susceptible to acid, alkaline and oxidative stresses, while relatively stable under photolytic and thermal dry stress conditions. Fourteen RSs including six process-related substances and eight degradation products were detected and identified in EVT-401 with positive ESI high-resolution TOF-MS analysis of their parent ions and the corresponding product mass spectra elucidation, and some of them were further verified by chemical synthesis and NMR spectroscopy. The specific LC–MS method developed for separation, identification and characterization of RSs is valuable for EVT-401 manufacturing process optimization and quality control.展开更多
Adoptive cell transfer(ACT)using chimeric antigen receptor(CAR)modified T cells and T cell receptor(TCR)engineered T cells has shown therapeutic efficacy in cancer treatment1,2.CAR T cells are widely applicable to tum...Adoptive cell transfer(ACT)using chimeric antigen receptor(CAR)modified T cells and T cell receptor(TCR)engineered T cells has shown therapeutic efficacy in cancer treatment1,2.CAR T cells are widely applicable to tumor patients because of their ability to directly identify tumor cells in an MHCindependent manner.展开更多
For permanent magnet synchronous machines(PMSMs),accurate machine model is critical for high performance maximum torque per ampere(MTPA)control.However,as motor speed increases,the nonlinearity such as core loss effec...For permanent magnet synchronous machines(PMSMs),accurate machine model is critical for high performance maximum torque per ampere(MTPA)control.However,as motor speed increases,the nonlinearity such as core loss effect will affect the accuracy of machine model and thus the performance of online MTPA control.This paper firstly investigates the performance of the model based MTPA control under different motor speeds through modeling,simulation and experiments,which indicates that the accuracy of MTPA control is greatly reduced especially under high-speeds due to machine nonlinearity.Hence,this paper proposes an efficient nonlinearity compensation model based on polynomial fitting to model and compensate the MTPA error as motor speed increases.Considering both core loss and magnetic saturation effects,the compensation model is a nonlinear polynomial of speed and stator current.To obtain the fitting data,a derivative modeling method is proposed to compute the actual and detected MTPA angles under different speeds,in which the derivative model of torque to current ratio is fitted and the MTPA angle is obtained by setting the derivative model to zero.The proposed compensation model is both computation effective and easy to use for MTPA control,as it computes the compensation term that can be directly combined to other model-based methods.The proposed model is evaluated with experiments and comparisons on a test motor to show the performance improvement.展开更多
For permanent magnet synchronous machine(PMSM),the machine model is critical to predict the operating states for motor control,which,however,can be greatly affected by system nonlinearities.Hence,this paper investigat...For permanent magnet synchronous machine(PMSM),the machine model is critical to predict the operating states for motor control,which,however,can be greatly affected by system nonlinearities.Hence,this paper investigates accurate machine modeling for control and parameter estimation.In the proposed approach,the PMSM model with saturated inductances is used as the base model,and this paper investigates modeling and compensation of the offsets to the base model due to system nonlinearities such as saturation and core loss effects for accurate machine modeling and voltage prediction.Specifically,the offsets to the base model are modeled using nonlinear functions with variable coefficients to compensate saturation and core loss effect,which can achieve better accuracy without changing the model structure.A differential estimation model is derived to estimate the model coefficients from a small amount of measurements with simplified procedure.Moreover,the model offset calculation is both computation and memory efficient with simplified implementation.The contribution is to improve the machine model accuracy and achieve precise voltage prediction for practical applications.Experiments,comparisons and the application to temperature estimation are conducted on a test interior PMSM to validate the proposed approach.展开更多
Massive multiple-input multiple-output (MIMO) is a key technology for the 5th Generation wireless communication systems. Joint spatial division and multiplexing (JSDM) method can reduce the cost of downlink training a...Massive multiple-input multiple-output (MIMO) is a key technology for the 5th Generation wireless communication systems. Joint spatial division and multiplexing (JSDM) method can reduce the cost of downlink training and feedback for CSIT of frequency-division duplexing (FDD) system. In this paper, we studied user grouping and user scheduling problems based on JSDM, and proposed an improved greedy user scheduling algorithm with lower complexity. Numerical results show that the user grouping and scheduling based on the proposed improved algorithm have much lower computational complexity while resulting in only a slight loss in system performance.展开更多
Most Chinese students learn English as a second language after they go to primary school.However,many articles showed that the best period of children to learn English was three years old to six years old.As researche...Most Chinese students learn English as a second language after they go to primary school.However,many articles showed that the best period of children to learn English was three years old to six years old.As researchers,we believe that Chinese children should learn English in kindergarten.We aim to find out from graduate Chinese students in Auburn Univerisity in the United States if Chinese children should learn English in kindergarten.We used qualitative research method,and thirteen participants who are graduate students in Auburn University were interviewed.We used a questionnaire to ask all participants seven questions.The results showed that 38%of participants studied English in kindergarten and 62%of interviewees learned English in primary school.Nine participants agreed that children should learn English in Chinese kindergarten,as they believed that children had strong ability to accept new knowledge at early ages.By doing this research,we want to help Chinese parents to realize that learning English at early ages is very important for every child,and we need to create a good environment for Chinese children to learn English.展开更多
Aim:This study aimed to translate a known drug-resistance mechanism of long-term CSFIR inhibition into multicellu-lar biomarkers that can serve as potential therapeutic targets as well as predictive markers for the su...Aim:This study aimed to translate a known drug-resistance mechanism of long-term CSFIR inhibition into multicellu-lar biomarkers that can serve as potential therapeutic targets as well as predictive markers for the survival of glioma patients.Methods:Using existing data from a published mouse study of drug resistance in immunotherapy for glioma,we identified mulicellular differentially expressed genes(DEGs)between drug-sensitive and drug-resistant mice and translated the DEGs in mouse genome to human homolog.We constructed correlation gene networks for drug re-sistance in mice and glioma patients and selected candidate genes via concordance analysis of human with mouse gene networks.Markers of drug resistance and an associated predictive signature for patient survival were developed using regularized Cox models with data of glioma patients from The Cancer Genome Atlas(TCGA)database.Predic-tive performance of the identified predictive signature was evaluated using an independent human dataset from the Chinese Glioma Genome Atlas(CGGA)database.Results:Fourteen genes(CCL22,ADCY2,PDK1,ZFP36,CP,CD2,PLAUR,ACAPI,COL5A1,FAM83D,PBK,FANCA,ANXA7,and TACC3)were identified as genetic biomarkers that were all associated with pathways in glioma progression and drug resistance.Five of the 14 genes(CCL22,ADCY2,PDK1,CD2,and COL5A1)were used to construct a signature that is predictive of patient survival in the proneural subtype GBM patients with an AUC under the time-dependent receiver operating characteristic(ROC)of 2-year survival equal to 0.89.This signature also shows promising predic-tive accuracy for the survival of LGG patients but not for non-proneural type GBMs.Conclusion:Our translational approach can utilize gene correlation networks from multiple types of cells in the tu-mor microenvironment of an imals.The identified biomarkers of drug resistance have good power to predict patient survival in some major subtypes of gliomas(the proneural subtype of GBM and LGG).The expression levels of the biomarkers of drug resistance may be modified for the development of personalized immunotherapies to prolong survival for a large portion of glioma patients.展开更多
The co-occurrence of extreme weather events and air pollution events,such as elevated fine particulate matter(PM2.5)and ozone(O3),poses a significant threat to human health,a concern that is anticipated to be exacerba...The co-occurrence of extreme weather events and air pollution events,such as elevated fine particulate matter(PM2.5)and ozone(O3),poses a significant threat to human health,a concern that is anticipated to be exacerbated under climate warming.Utilizing a 9-year dataset of surface air pollutant observations and reanalysis data,this study investigated the large-scale synoptic and weather drivers behind the co-occurrence of PM2.5and O3extremes in China.These co-occurrences are mostly observed during the warm season(March to October)and are particularly prevalent(25.8 days y^(r-1))in cleaner regions situated in South China.Such co-occurrences are usually associated with elevated air temperatures(~27.7°C),lower wind speeds(~1.4 ms^(-1))and atmospheric humidity(~51.9%).Notably,a substantial proportion of these co-occurrences(up to 76.4%)coincide with extreme weather linked to stagnant weather and extreme heat conditions.By employing an objective clustering approach,we identified the typical synoptic systems conducive to the widespread co-occurrence of PM2.5and O3extremes,including the Western Pacific Subtropical High,Northeast Blocking High,Mongolian High,and typhoons.These findings underscore a robust correlation between the co-occurrence of PM2.5and O3extremes and the annual variations in extreme weather and prevailing weather patterns,suggesting an increased likelihood of concurrent air pollution and extreme weather episodes under a warming climate across China.展开更多
In this paper,a precise and computationally efficient method for estimating multiparameter of permanent magnet synchronous motors(PMSMs)is proposed.This method can realize decoupling estimation with a small amount of ...In this paper,a precise and computationally efficient method for estimating multiparameter of permanent magnet synchronous motors(PMSMs)is proposed.This method can realize decoupling estimation with a small amount of data at a single speed,and considers the inductance correlation to improve the estimation accuracy.The saturation in the stator frame is first modeled,and then the related inductance model in the rotating frame is derived.The estimation model is established based on the related inductance model,which is modeled by polynomials of d-axis current(I_(d))for a given q-axis current(I_(q)).Then,the influence of permanent magnet(PM)flux linkage on inductance estimation can be eliminated by using the partial derivative of the correlated inductance model.The estimation model fully explores the inductance correlation and can realize the decoupling of PM flux linkage(λ_(0))and inductance,which greatly improves the inductance estimation accuracy,especially when Id is small.Moreover,this paper realizes the estimation of distortion voltage,PM flux linkage,and stator resistance based on the derived electrical model and mechanical model.Compared with the existing method,this method can use a small amount of data at a single speed to model voltage,which can effectively reduce the influence of measurement noise and improve the calculation efficiency.Experimental verification on a laboratory PMSM prototype shows that the method’s performance of the proposed method is better than existing methods under various working conditions.展开更多
Intensive human activity has brought about unprecedented climate and environmental crises, in which concurrent heatwaves and ozone extremes pose the most serious threats. However, a limited understanding of the compre...Intensive human activity has brought about unprecedented climate and environmental crises, in which concurrent heatwaves and ozone extremes pose the most serious threats. However, a limited understanding of the comprehensive mechanism hinders our ability to mitigate such compound events, especially in densely populated regions like China. Here, based on field observations and climate-chemistry coupled modelling, we elucidate the linkage between human activities and the climate system in heatrelated ozone pollution. In China, we have observed that both the frequency and intensity of heatwaves have almost tripled since the beginning of this century. Moreover, these heatwaves are becoming more common in urban clusters with serious ozone pollution. Persistent heatwaves during the extremely hot and dry summers of 2013 and 2022 accelerated photochemical ozone production by boosting anthropogenic and biogenic emissions, and aggravated ozone accumulation by suppressing dry deposition due to water-stressed vegetation, leading to a more than 30% increase in ozone pollution in China's urban areas. The sensitivity of ozone to heat is demonstrated to be substantially modulated by anthropogenic emissions, and China's clean air policy may have altered the relationship between ozone and temperature. Climate model projections further highlight that the high-emission climate-socioeconomic scenario tends to intensify the concurrent heat and ozone extremes in the next century. Our results underscore that the implementation of a strict emission strategy will significantly reduce the co-occurrence of heatwaves and ozone extremes, achieving climate and environmental co-benefits.展开更多
Although chimeric antigen receptor(CAR)T cells have become an important treatment option for patients with relapsed/refractory B-cell malignancies,more than 60%of patients with diffuse large B-cell lymphoma(DLBCL)trea...Although chimeric antigen receptor(CAR)T cells have become an important treatment option for patients with relapsed/refractory B-cell malignancies,more than 60%of patients with diffuse large B-cell lymphoma(DLBCL)treated with CAR-T cell therapies fail to achieve a durable response.To reveal changes in CAR-T cell therapy and identify response biomarkers,we conducted a retrospective analysis of pre-manufacture source T cells and CAR-T cell products and their association with outcome in 58 patients with r/rDLBCL who received tandem CD19/CD20 CAR-T cell therapy.We performed bulk RNA-Seq,single-cell RNA-Seq,and paired T cell receptor sequencing on CAR-T cell products and pre-manufacture T cells from DLBCL patients.We note that a CD8+stem cell-like memory T cell population with a higher proportion and enhanced activating capacity of the CAR-T cell products was key to achieving durable clinical response.By analysing autologously-derived,pre-manufacture T cells,our data suggest that heterogeneity in the cellular and molecular features of pre-manufacture T cells contribute to the variation in efficacy after CAR-T cell therapy in DLBCL.The differences in anti-tumour efficacy of CAR-T cells among patients with different clinical outcomes appear to be due to the loss of CCR7 gene expression,coupled with increased expression of activation-and inhibitor-related genes in the CD8+naïve-T cell populations among the apheresis T cells from patients with a poor molecular response.These findings significantly advance our understanding of the underlying molecular determinants of pre-manufacture T cell function.展开更多
基金co-supported by the National Natural Science Foundation of China(Nos.U24B20157,62203031)the Natural Science Foundation of Beijing Municipality,China(No.4242041)+2 种基金the Natural Science Foundation of Zhejiang Province,China(No.LY24F030002)the Aeronautical ScienceFoundation of China(No.2024Z066051001)the Fundamental Research Funds for the Central Universities of China。
文摘The capture zones of the continuous and pulsed guidance laws in the pursuit-evasion game are analytically discussed in this paper to provide deep insights into the capturability distinction between the continuous guidance law and the pulsed guidance law.Specifically,first,in the pursuit-evasion game,various capture cases are defined regarding the Zero-Effort Miss distance(ZEM)to facilitate the capturability analysis.Then,for both the evader and the pursuer,the Linear-Quadratic Differential Game(LQDG)guidance laws concerning the continuous acceleration and the pulsed acceleration are converted into a unified form.In each capture case,the optimal solution existence conditions are derived,and the corresponding capture zones are formulated.The discussion on the capture zones shows that if the optimal solution exists,the distinction between the pulsed guidance law and the continuous guidance law can be neglected under small guidance effort weight.However,the capture zone of the continuous guidance law is larger than that of the pulsed guidance law with large pursuer guidance effort weight,but smaller with large evader guidance effort weight.Finally,various simulations are conducted to illustrate the distinction of the continuous and pulsed guidance laws,as well as the impact of the acceleration ratio and the time constant ratio on the capturability.
基金supported by the earmarked fund for the Modern Agro-Industry Technology Research System (No.CARS-19)the Innovative Research Team in Chinese Academy of Agricultural Sciences (No.CAAS ASTIP-2014-TRICAAS).
文摘Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.
基金supported by Shenzhen Science and Technology Program under Grant JCYJ20250604175412017the National Natural Science Foundation of China under Grant 62473387+1 种基金the Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) under Grant SML2024SP007in part by the Department of Science and Technology of Guangdong Province under Grant. 2021QN020085。
文摘In permanent magnet synchronous machine(PMSM) drives, temperature information is critical to achieve reliable and high-performance control. The popular model-based estimation methods are based on extracting temperature dependent terms from the voltages using the machine model. The estimation accuracy under low speed or load can be greatly affected by the model uncertainty and noise due to low signal-tonoise ratio. This paper presents a high frequency(HF) position offset injection-based winding and permanent magnet(PM) temperature decoupled estimation approach for PMSMs to achieve accurate and robust temperature estimation among a wide speed range especially under low-speed conditions. In the proposed approach, a small HF position offset is injected into the machine to construct a decoupled winding and PM temperature estimation model, in which the winding and PM temperatures are independently estimated from HF excitations. The temperature estimation is independent from the fundamental model and parameter variation, and it achieves high signal-tonoise ratio under low-speed conditions. Moreover, the temperature estimation is also not affected by magnetic saturation and inverter distortion, which can improve the accuracy and robustness of temperature estimation. The proposed approach is validated with experiments and comparisons on a laboratory machine under various operating conditions.
基金Project supported by the National Natural Science Foundation of China(Grant No.62375140)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(Grant No.KYCX241191 and SJCX250315)the Open Research Fund of the National Laboratory of Solid State Microstructures(Grant No.M36055)。
文摘A mode-pairing quantum key distribution based on heralded pair-coherent source with passive decoy-states is proposed,named HPCS-PDS-MP-QKD protocol,where the light sources at Alice and Bob sides are changed to heralded pair-coherent sources,and devices designed to implement passive decoy states are included at the transmitter sides to generate the decoy state pulses in the decoy-state window passively.With the defined efficient events and the designed pairing strategy,the key bits and bases can be obtained by data post-processing.Numerical simulation results verify the feasibility of the proposed protocol.The results show that the proposed protocol can exceed PLOB when the pairing interval setting is greater than 10^(3),and the transmission distance exceeds 200 km.When the key transmission distance reaches 300 km and the maximum pairing interval is equivalent to 1,its performance is improved by nearly 1.8 times compared to the original MP-QKD protocol with a weak coherent source(WCS-MP-QKD),and by 6.8 times higher than that of WCS-MPQKD with passive decoy states(WCS-PDS-MP-QKD).Meanwhile,the key transmission distance can reach 480 km,and surpasses the WCS-PDS-MP-QKD protocol by nearly 40 km.When the total pulse length is greater than 10^(11),the key generation rate is almost equal to that of infinite pulses.It is a promising QKD protocol that breaks the PLOB bound without requiring phase tracking and locking,has a longer transmission distance and a higher key generation rate,and eliminates the potential of side channel attack.
基金supported in part by the National Natural Science Foundation of China(62473387)the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(SML2023SP241)the Department of Science and Technology of Guangdong Province(2021QN020085)。
文摘For permanent magnet synchronous machines(PMSMs),accurate inductance is critical for control design and condition monitoring.Owing to magnetic saturation,existing methods require nonlinear saturation model and measurements from multiple load/current conditions,and the estimation is relying on the accuracy of saturation model and other machine parameters in the model.Speed harmonic produced by harmonic currents is inductance-dependent,and thus this paper explores the use of magnitude and phase angle of the speed harmonic for accurate inductance estimation.Two estimation models are built based on either the magnitude or phase angle,and the inductances can be from d-axis voltage and the magnitude or phase angle,in which the filter influence in harmonic extraction is considered to ensure the estimation performance.The inductances can be estimated from the measurements under one load condition,which is free of saturation model.Moreover,the inductance estimation is robust to the change of other machine parameters.The proposed approach can effectively improve estimation accuracy especially under the condition with low current magnitude.Experiments and comparisons are conducted on a test PMSM to validate the proposed approach.
基金This work was supported by the Tianjin Sci-Tech Projects(No.16YFZCSY01070),China.
文摘With the recent upsurge of studies in the field of microbiology,we have learned more about the complexity of the gastrointestinal microecosystem.More than 30 genera and 1000 species of gastrointestinal microflora have been found.The structure of the normal microflora is relatively stable,and is in an interdependent and restricted dynamic equilibrium with the body.In recent years,studies have shown that there is a potential relationship between gastrointestinal microflora imbalance and gastric cancer(GC)and precancerous lesions.So,restoring the balance of gastrointestinal microflora is of great significance.Moreover,intervention in gastric premalignant condition(GPC),also known as precancerous lesion of gastric cancer(PLGC),has been the focus of current clinical studies.The holistic view of traditional Chinese medicine(TCM)is consistent with the microecology concept,and oral TCM can play a two-way regulatory role directly with the microflora in the digestive tract,restoring the homeostasis of gastrointestinal microflora to prevent canceration.However,large gaps in knowledge remain to be addressed.This review aims to provide new ideas and a reference for clinical practice.
基金supported by the Tianjin Sci-Tech Project(No.16YFZCSY01070),China。
文摘Vascular endothelial growth factor(VEGF)is the main regulator of physiological angiogenesis during embryonic development,bone growth,and reproductive function,and it also participates in a series of pathological changes.Traditional Chinese medicine(TCM),with a history of more than 2000 years,has been widely used in clinical practice,while the exploration of its mechanisms has only begun.This review summarizes the research of recent years on the influence of TCM on VEGF.It is found that many Chinese medicines and recipes have a regulatory effect on VEGF,indicating that Chinese medicine has broad prospects as a complementary and alternative therapy,providing new treatment ideas for clinical applications and the theoretical basis for research on the mechanisms of TCM.
基金supported in part by the National Natural Science Foundation of China under Grant 52105079 and 62103455。
文摘This paper proposes a virtual position-offset injection based permanent magnet temperature estimation approach for permanent magnet synchronous machines(PMSMs). The concept of virtual position-offset injection is mathematically transforming the machine model to a virtual frame with a position-offset. The virtual frame temperature estimation model is derived to calculate the permanent magnet temperature(PMT) directly from the measurements with computation efficiency. The estimation model involves a combined inductance term, which can simplify the establishment of saturation compensation model with less measurements. Moreover, resistance and inverter distorted terms are cancelled in the estimation model, which can improve the robustness to the winding temperature rise and inverter distortion. The proposed approach can achieve simplified computation in temperature estimation and reduced memory usage in saturation compensation. While existing model-based approaches could be affected by either the need of resistance and inverter information or complex saturation compensation. Experiments are conducted on the test machine to verify the proposed approach under various operating conditions.
文摘A sensitive and selective method was developed for the separation and characterization of related substances(RSs) in EVT-401 by hyphenated LC–MS techniques. Complete separation of the RSs was achieved with an Inertsil ODS-SP column(250 mm×4.6 mm, 5 μm) by linear gradient elution using a mobile phase consisting of 0.2% formic acid solution, methanol and acetonitrile. EVT-401 was found to be susceptible to acid, alkaline and oxidative stresses, while relatively stable under photolytic and thermal dry stress conditions. Fourteen RSs including six process-related substances and eight degradation products were detected and identified in EVT-401 with positive ESI high-resolution TOF-MS analysis of their parent ions and the corresponding product mass spectra elucidation, and some of them were further verified by chemical synthesis and NMR spectroscopy. The specific LC–MS method developed for separation, identification and characterization of RSs is valuable for EVT-401 manufacturing process optimization and quality control.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.82150108,31991171,and 81830002 to W.H.,and Grant No.82102892 to C.T.)。
文摘Adoptive cell transfer(ACT)using chimeric antigen receptor(CAR)modified T cells and T cell receptor(TCR)engineered T cells has shown therapeutic efficacy in cancer treatment1,2.CAR T cells are widely applicable to tumor patients because of their ability to directly identify tumor cells in an MHCindependent manner.
基金supported by in part by the National Natural Science Foundation of China(62473387,52105079,62103455)the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(SML2023SP241)。
文摘For permanent magnet synchronous machines(PMSMs),accurate machine model is critical for high performance maximum torque per ampere(MTPA)control.However,as motor speed increases,the nonlinearity such as core loss effect will affect the accuracy of machine model and thus the performance of online MTPA control.This paper firstly investigates the performance of the model based MTPA control under different motor speeds through modeling,simulation and experiments,which indicates that the accuracy of MTPA control is greatly reduced especially under high-speeds due to machine nonlinearity.Hence,this paper proposes an efficient nonlinearity compensation model based on polynomial fitting to model and compensate the MTPA error as motor speed increases.Considering both core loss and magnetic saturation effects,the compensation model is a nonlinear polynomial of speed and stator current.To obtain the fitting data,a derivative modeling method is proposed to compute the actual and detected MTPA angles under different speeds,in which the derivative model of torque to current ratio is fitted and the MTPA angle is obtained by setting the derivative model to zero.The proposed compensation model is both computation effective and easy to use for MTPA control,as it computes the compensation term that can be directly combined to other model-based methods.The proposed model is evaluated with experiments and comparisons on a test motor to show the performance improvement.
基金supported by in part by the National Natural Science Foundation of China(52105079,62103455)the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(SML2023SP241)。
文摘For permanent magnet synchronous machine(PMSM),the machine model is critical to predict the operating states for motor control,which,however,can be greatly affected by system nonlinearities.Hence,this paper investigates accurate machine modeling for control and parameter estimation.In the proposed approach,the PMSM model with saturated inductances is used as the base model,and this paper investigates modeling and compensation of the offsets to the base model due to system nonlinearities such as saturation and core loss effects for accurate machine modeling and voltage prediction.Specifically,the offsets to the base model are modeled using nonlinear functions with variable coefficients to compensate saturation and core loss effect,which can achieve better accuracy without changing the model structure.A differential estimation model is derived to estimate the model coefficients from a small amount of measurements with simplified procedure.Moreover,the model offset calculation is both computation and memory efficient with simplified implementation.The contribution is to improve the machine model accuracy and achieve precise voltage prediction for practical applications.Experiments,comparisons and the application to temperature estimation are conducted on a test interior PMSM to validate the proposed approach.
文摘Massive multiple-input multiple-output (MIMO) is a key technology for the 5th Generation wireless communication systems. Joint spatial division and multiplexing (JSDM) method can reduce the cost of downlink training and feedback for CSIT of frequency-division duplexing (FDD) system. In this paper, we studied user grouping and user scheduling problems based on JSDM, and proposed an improved greedy user scheduling algorithm with lower complexity. Numerical results show that the user grouping and scheduling based on the proposed improved algorithm have much lower computational complexity while resulting in only a slight loss in system performance.
文摘Most Chinese students learn English as a second language after they go to primary school.However,many articles showed that the best period of children to learn English was three years old to six years old.As researchers,we believe that Chinese children should learn English in kindergarten.We aim to find out from graduate Chinese students in Auburn Univerisity in the United States if Chinese children should learn English in kindergarten.We used qualitative research method,and thirteen participants who are graduate students in Auburn University were interviewed.We used a questionnaire to ask all participants seven questions.The results showed that 38%of participants studied English in kindergarten and 62%of interviewees learned English in primary school.Nine participants agreed that children should learn English in Chinese kindergarten,as they believed that children had strong ability to accept new knowledge at early ages.By doing this research,we want to help Chinese parents to realize that learning English at early ages is very important for every child,and we need to create a good environment for Chinese children to learn English.
基金supported by research grants P30CA016087,P50CA225450,P30AG066512 from the National Institute of Health(NIH).
文摘Aim:This study aimed to translate a known drug-resistance mechanism of long-term CSFIR inhibition into multicellu-lar biomarkers that can serve as potential therapeutic targets as well as predictive markers for the survival of glioma patients.Methods:Using existing data from a published mouse study of drug resistance in immunotherapy for glioma,we identified mulicellular differentially expressed genes(DEGs)between drug-sensitive and drug-resistant mice and translated the DEGs in mouse genome to human homolog.We constructed correlation gene networks for drug re-sistance in mice and glioma patients and selected candidate genes via concordance analysis of human with mouse gene networks.Markers of drug resistance and an associated predictive signature for patient survival were developed using regularized Cox models with data of glioma patients from The Cancer Genome Atlas(TCGA)database.Predic-tive performance of the identified predictive signature was evaluated using an independent human dataset from the Chinese Glioma Genome Atlas(CGGA)database.Results:Fourteen genes(CCL22,ADCY2,PDK1,ZFP36,CP,CD2,PLAUR,ACAPI,COL5A1,FAM83D,PBK,FANCA,ANXA7,and TACC3)were identified as genetic biomarkers that were all associated with pathways in glioma progression and drug resistance.Five of the 14 genes(CCL22,ADCY2,PDK1,CD2,and COL5A1)were used to construct a signature that is predictive of patient survival in the proneural subtype GBM patients with an AUC under the time-dependent receiver operating characteristic(ROC)of 2-year survival equal to 0.89.This signature also shows promising predic-tive accuracy for the survival of LGG patients but not for non-proneural type GBMs.Conclusion:Our translational approach can utilize gene correlation networks from multiple types of cells in the tu-mor microenvironment of an imals.The identified biomarkers of drug resistance have good power to predict patient survival in some major subtypes of gliomas(the proneural subtype of GBM and LGG).The expression levels of the biomarkers of drug resistance may be modified for the development of personalized immunotherapies to prolong survival for a large portion of glioma patients.
基金supported by the National Natural Science Foundation of China(Grant Nos.42293322,42275100)the National Key Basic Research Development Program of China(Grant Nos 2024YFC3711905,2022YFC3701105)the Research Funds for the Frontiers Science Center for Critical Earth Material Cycling,Nanjing University。
文摘The co-occurrence of extreme weather events and air pollution events,such as elevated fine particulate matter(PM2.5)and ozone(O3),poses a significant threat to human health,a concern that is anticipated to be exacerbated under climate warming.Utilizing a 9-year dataset of surface air pollutant observations and reanalysis data,this study investigated the large-scale synoptic and weather drivers behind the co-occurrence of PM2.5and O3extremes in China.These co-occurrences are mostly observed during the warm season(March to October)and are particularly prevalent(25.8 days y^(r-1))in cleaner regions situated in South China.Such co-occurrences are usually associated with elevated air temperatures(~27.7°C),lower wind speeds(~1.4 ms^(-1))and atmospheric humidity(~51.9%).Notably,a substantial proportion of these co-occurrences(up to 76.4%)coincide with extreme weather linked to stagnant weather and extreme heat conditions.By employing an objective clustering approach,we identified the typical synoptic systems conducive to the widespread co-occurrence of PM2.5and O3extremes,including the Western Pacific Subtropical High,Northeast Blocking High,Mongolian High,and typhoons.These findings underscore a robust correlation between the co-occurrence of PM2.5and O3extremes and the annual variations in extreme weather and prevailing weather patterns,suggesting an increased likelihood of concurrent air pollution and extreme weather episodes under a warming climate across China.
基金sponsored by Ministry of Natural Resources in Guangdong Province(No.GDNRC[2024]52)。
文摘In this paper,a precise and computationally efficient method for estimating multiparameter of permanent magnet synchronous motors(PMSMs)is proposed.This method can realize decoupling estimation with a small amount of data at a single speed,and considers the inductance correlation to improve the estimation accuracy.The saturation in the stator frame is first modeled,and then the related inductance model in the rotating frame is derived.The estimation model is established based on the related inductance model,which is modeled by polynomials of d-axis current(I_(d))for a given q-axis current(I_(q)).Then,the influence of permanent magnet(PM)flux linkage on inductance estimation can be eliminated by using the partial derivative of the correlated inductance model.The estimation model fully explores the inductance correlation and can realize the decoupling of PM flux linkage(λ_(0))and inductance,which greatly improves the inductance estimation accuracy,especially when Id is small.Moreover,this paper realizes the estimation of distortion voltage,PM flux linkage,and stator resistance based on the derived electrical model and mechanical model.Compared with the existing method,this method can use a small amount of data at a single speed to model voltage,which can effectively reduce the influence of measurement noise and improve the calculation efficiency.Experimental verification on a laboratory PMSM prototype shows that the method’s performance of the proposed method is better than existing methods under various working conditions.
基金supported by the National Key Basic Research Development Program of China (2022YFC3701105)the National Natural Science Foundation of China (42293322 and 42275100)。
文摘Intensive human activity has brought about unprecedented climate and environmental crises, in which concurrent heatwaves and ozone extremes pose the most serious threats. However, a limited understanding of the comprehensive mechanism hinders our ability to mitigate such compound events, especially in densely populated regions like China. Here, based on field observations and climate-chemistry coupled modelling, we elucidate the linkage between human activities and the climate system in heatrelated ozone pollution. In China, we have observed that both the frequency and intensity of heatwaves have almost tripled since the beginning of this century. Moreover, these heatwaves are becoming more common in urban clusters with serious ozone pollution. Persistent heatwaves during the extremely hot and dry summers of 2013 and 2022 accelerated photochemical ozone production by boosting anthropogenic and biogenic emissions, and aggravated ozone accumulation by suppressing dry deposition due to water-stressed vegetation, leading to a more than 30% increase in ozone pollution in China's urban areas. The sensitivity of ozone to heat is demonstrated to be substantially modulated by anthropogenic emissions, and China's clean air policy may have altered the relationship between ozone and temperature. Climate model projections further highlight that the high-emission climate-socioeconomic scenario tends to intensify the concurrent heat and ozone extremes in the next century. Our results underscore that the implementation of a strict emission strategy will significantly reduce the co-occurrence of heatwaves and ozone extremes, achieving climate and environmental co-benefits.
基金This work was supported in part by the National Natural Science Foundation of China(Nos.81830002,31991171,82150108 and 82102892)Translational Research Grant of NCRCH(2021WWC04).
文摘Although chimeric antigen receptor(CAR)T cells have become an important treatment option for patients with relapsed/refractory B-cell malignancies,more than 60%of patients with diffuse large B-cell lymphoma(DLBCL)treated with CAR-T cell therapies fail to achieve a durable response.To reveal changes in CAR-T cell therapy and identify response biomarkers,we conducted a retrospective analysis of pre-manufacture source T cells and CAR-T cell products and their association with outcome in 58 patients with r/rDLBCL who received tandem CD19/CD20 CAR-T cell therapy.We performed bulk RNA-Seq,single-cell RNA-Seq,and paired T cell receptor sequencing on CAR-T cell products and pre-manufacture T cells from DLBCL patients.We note that a CD8+stem cell-like memory T cell population with a higher proportion and enhanced activating capacity of the CAR-T cell products was key to achieving durable clinical response.By analysing autologously-derived,pre-manufacture T cells,our data suggest that heterogeneity in the cellular and molecular features of pre-manufacture T cells contribute to the variation in efficacy after CAR-T cell therapy in DLBCL.The differences in anti-tumour efficacy of CAR-T cells among patients with different clinical outcomes appear to be due to the loss of CCR7 gene expression,coupled with increased expression of activation-and inhibitor-related genes in the CD8+naïve-T cell populations among the apheresis T cells from patients with a poor molecular response.These findings significantly advance our understanding of the underlying molecular determinants of pre-manufacture T cell function.
