Magnetic Resonance Imaging(MRI)has a pivotal role in medical image analysis,for its ability in supporting disease detection and diagnosis.Fuzzy C-Means(FCM)clustering is widely used for MRI segmentation due to its abi...Magnetic Resonance Imaging(MRI)has a pivotal role in medical image analysis,for its ability in supporting disease detection and diagnosis.Fuzzy C-Means(FCM)clustering is widely used for MRI segmentation due to its ability to handle image uncertainty.However,the latter still has countless limitations,including sensitivity to initialization,susceptibility to local optima,and high computational cost.To address these limitations,this study integrates Grey Wolf Optimization(GWO)with FCM to enhance cluster center selection,improving segmentation accuracy and robustness.Moreover,to further refine optimization,Fuzzy Entropy Clustering was utilized for its distinctive features from other traditional objective functions.Fuzzy entropy effectively quantifies uncertainty,leading to more well-defined clusters,improved noise robustness,and better preservation of anatomical structures in MRI images.Despite these advantages,the iterative nature of GWO and FCM introduces significant computational overhead,which restricts their applicability to high-resolution medical images.To overcome this bottleneck,we propose a Parallelized-GWO-based FCM(P-GWO-FCM)approach using GPU acceleration,where both GWO optimization and FCM updates(centroid computation and membership matrix updates)are parallelized.By concurrently executing these processes,our approach efficiently distributes the computational workload,significantly reducing execution time while maintaining high segmentation accuracy.The proposed parallel method,P-GWO-FCM,was evaluated on both simulated and clinical brain MR images,focusing on segmenting white matter,gray matter,and cerebrospinal fluid regions.The results indicate significant improvements in segmentation accuracy,achieving a Jaccard Similarity(JS)of 0.92,a Partition Coefficient Index(PCI)of 0.91,a Partition Entropy Index(PEI)of 0.25,and a Davies-Bouldin Index(DBI)of 0.30.Experimental comparisons demonstrate that P-GWO-FCM outperforms existing methods in both segmentation accuracy and computational efficiency,making it a promising solution for real-time medical image segmentation.展开更多
Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collab...Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collaboration project between the French Atomic and Alternative Energy Commission(CEA) and Jožef Stefan Institute(JSI), Slovenia, have been performed at the JSI TRIGA reactor for the experimental assessment of nuclear heating in fission and fusion-relevant materials by the differential calorimetry technique, based on the CALMOS and CARMEN differential calorimeters, previously developed at CEA. The results of the first campaign performed at reactor powers between 100 and 250 kW have already been reported, highlighting some measurement difficulties. Therefore, the second campaign was performed at a lower reactor power of 30 kW to overcome these issues. Moreover, a computational analysis of the experiments was performed using the JSIR2S code package to calculate the nuclear heating levels. Both experiments and their reproduction by simulations are described in detail. We present a comparison of the previously reported measured nuclear heating values of the first campaign with the computational results, with consistent underestimation by simulations by 8–35%. We report the experimental and computational results for the second experimental campaign performed at a reactor power of 30 kW. The simulated heating values were in agreement with the measurements within the measured heating uncertainty, with simulated heating 2.7–11.3% lower than the experimental values.展开更多
A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-d...A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-dimensional cusp boundary from a two-dimensional X-ray image because the detected X-ray signals will be integrated along the line of sight.In this work,a global magnetohydrodynamic code was used to simulate the X-ray images and photon count images,assuming an interplanetary magnetic field with a pure Bz component.The assumption of an elliptic cusp boundary at a given altitude was used to trace the equatorward and poleward boundaries of the cusp from a simulated X-ray image.The average discrepancy was less than 0.1 RE.To reduce the influence of instrument effects and cosmic X-ray backgrounds,image denoising was considered before applying the method above to SXI photon count images.The cusp boundaries were reasonably reconstructed from the noisy X-ray image.展开更多
Substantial advancements have been achieved in Tunnel Boring Machine(TBM)technology and monitoring systems,yet the presence of missing data impedes accurate analysis and interpretation of TBM monitoring results.This s...Substantial advancements have been achieved in Tunnel Boring Machine(TBM)technology and monitoring systems,yet the presence of missing data impedes accurate analysis and interpretation of TBM monitoring results.This study aims to investigate the issue of missing data in extensive TBM datasets.Through a comprehensive literature review,we analyze the mechanism of missing TBM data and compare different imputation methods,including statistical analysis and machine learning algorithms.We also examine the impact of various missing patterns and rates on the efficacy of these methods.Finally,we propose a dynamic interpolation strategy tailored for TBM engineering sites.The research results show that K-Nearest Neighbors(KNN)and Random Forest(RF)algorithms can achieve good interpolation results;As the missing rate increases,the interpolation effect of different methods will decrease;The interpolation effect of block missing is poor,followed by mixed missing,and the interpolation effect of sporadic missing is the best.On-site application results validate the proposed interpolation strategy's capability to achieve robust missing value interpolation effects,applicable in ML scenarios such as parameter optimization,attitude warning,and pressure prediction.These findings contribute to enhancing the efficiency of TBM missing data processing,offering more effective support for large-scale TBM monitoring datasets.展开更多
Multiple sclerosis(MS)is the most common chronic disease of the central nervous system(CNS)in young adults and represents the first cause of severe handicap,originally non-traumatic(Oh et al.,2018).MS is chara cterize...Multiple sclerosis(MS)is the most common chronic disease of the central nervous system(CNS)in young adults and represents the first cause of severe handicap,originally non-traumatic(Oh et al.,2018).MS is chara cterized by the infiltration of auto reactive lymphocytes specific to myelin through the blood-brain barrier,which results in the appearance of inflammatory demyelinating lesions caused by the death of the central nervous system myelinating cells,oligodendrocytes(Oh et al.,2018).There is a prevalence sexual with a ratio of three times more affected women than men.展开更多
Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are o...Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids.展开更多
In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic...In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic solutions of some nonlinear ODEs together with some classical,19th-century results,can be turned into algorithms(thus avoiding ad hoc assumptions)which provide all(as opposed to some)solutions in a precise class.To illustrate these methods,we present some new such exact solutions,physically relevant.展开更多
A gradient nanostructured layer was fabricated on the surface of TA15(Ti-6Al-2Zr-1Mo-1V)alloy(produced by selective laser melting)using severe shot peening(SSP).This study focuses on the evolution of the microstructur...A gradient nanostructured layer was fabricated on the surface of TA15(Ti-6Al-2Zr-1Mo-1V)alloy(produced by selective laser melting)using severe shot peening(SSP).This study focuses on the evolution of the microstructure and the mechanism of grain refinement in TA15 titanium alloy during SSP treatment.Transmission electron microscopyand Rietveld refinement methods were employed.The residual stress and microhardness variations with depth were also characterized.The results show:(1)At the initial stage of deformation,plastic deformation is primarily accommodated through twinning and dislocation slip.(2)As the strain increases,twinning disappears,and dislocations interact to form tangles.Some dislocations annihilate and rearrange into subgrain boundaries,subdividing the original grains into subgrains.(3)With continued dislocation activity,the subgrain size decreases until nanocrystals are formed through the dynamic rotational recrystallization.SSP introduced compressive residual stress(CRS)in the near-surface layer of the material,with the maximum CRS of approximately−1141 MPa observed in the subsurface layer.It also induced work hardening,increasing the surface hardness to approximately 479 HV.However,the surface roughness increases,leading to a slight deterioration in surface quality.展开更多
We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The...We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The free-electron contribution is described by the Maynard–Deutsch–Zimmerman formula,and the bound-electron contribution relies on the Bethe formula with corrections,in particular taking into account density and shell effects.The results of the bound-state computation using three different parametric potentials are investigated within the Garbet formalism for the mean excitation energy.The first parametric potential is due to Green,Sellin,and Zachor,the second one was proposed by Yunta,and the third one was introduced by Klapisch in the framework of atomic-structure computations.The results are compared with those of self-consistent average-atom calculations.This approach correctly bridges the limits of neutral and fully ionized matter.展开更多
Transition metals have garnered significant attention for their roles in addressing energy shortages and environmental water pollution.Their multivalent states and unique electron transfer properties facilitate charge...Transition metals have garnered significant attention for their roles in addressing energy shortages and environmental water pollution.Their multivalent states and unique electron transfer properties facilitate charge transfer in the conversion reaction,expedite energy conversion,and achieve low-energy water treatment.This review comprehensively explores the fundamental mechanisms and practical applications of transition metals in water treatment,including adsorption,photocatalysis,electrocatalysis,photoelectrocatalysis,and other technologies.The feasibility of water treatment using transition metal-based materials is demonstrated through theoretical studies on typical transition metals employed in these water treatment technologies while emphasizing the potential for optimizing material performance through strategies like structural design,defect engineering,crystal engineering,composite materials,surface modification,and atomic catalysts.In addition,the utilization of transition metal-based materials in practical wastewater treatment is comprehensively reviewed.Finally,the challenges and perspectives of transition metal-based materials in practical wastewater treatment are outlined,providing a theoretical foundation and guidance for future research and engineering advancements.展开更多
In the field of discretization-based meshfree/meshless methods,the improvements in the higher-order consistency,stability,and computational efficiency are of great concerns in computational science and numerical solut...In the field of discretization-based meshfree/meshless methods,the improvements in the higher-order consistency,stability,and computational efficiency are of great concerns in computational science and numerical solutions to partial differential equations.Various alternative numerical methods of the finite particle method(FPM)frame have been extended from mathematical theories to numerical applications separately.As a comprehensive numerical scheme,this study suggests a unified resolved program for numerically investigating their accuracy,stability,consistency,computational efficiency,and practical applicability in industrial engineering contexts.The high-order finite particle method(HFPM)and corrected methods based on the multivariate Taylor series expansion are constructed and analyzed to investigate the whole applicability in different benchmarks of computational fluid dynamics.Specifically,four benchmarks are designed purposefully from statical exact solutions to multifaceted hydrodynamic tests,which possess different numerical performances on the particle consistency,numerical discretized forms,particle distributions,and transient time evolutional stabilities.This study offers a numerical reference for the current unified resolved program.展开更多
Recent progress in the design and fabrication of thermal metasurfaces allows a broad control of the properties of light emission,including its polarization state.Stokes polarimetry is a key approach to accurately char...Recent progress in the design and fabrication of thermal metasurfaces allows a broad control of the properties of light emission,including its polarization state.Stokes polarimetry is a key approach to accurately characterize partially polarized light.The quality of a Stokes polarimeter made of retarders and polarizers can be evaluated by use of metrics such as the equally weighted variance or the condition number of the matrix representing the polarimeter.Although specific instrument configurations are used to maximize polarimeter performance at a given wavelength,such optimal solutions are not spectrally robust because of the wave-length dependence of retardance.This becomes an issue in characterizing broadband thermal sources in the infrared.We report a Stokes polarimeter making use of five polarization analysis states and consisting of two simple and common optical elements—a crystalline waveplate and a linear polarizer.We combine this setup with a Fourier transform infrared spectrometer to measure accurately in a single set of acqui-sitions without requiring any spectral filtering,and to measure the polarization state with accuracy over a broad range of wavelengths.Such a Stokes polarimeter allows for close to optimal noise in the data reduc-tion process in the mid-wave infrared spectral range from 2.5 to 5μm.展开更多
In this paper, we study the stability of a class of conformable fractional-order systems using the Lyapunov function. We assume that the nonlinear part of the system satisfies the one-sided Lipschitz condition and the...In this paper, we study the stability of a class of conformable fractional-order systems using the Lyapunov function. We assume that the nonlinear part of the system satisfies the one-sided Lipschitz condition and the quadratic inner-bounded condition. We provide some sufficient conditions that ensure the asymptotic stability of the system. Furthermore, we present the construction of a feedback stabilizing controller for conformable fractional bilinear systems.展开更多
Several aspects of the internal structure of pseudoscalar mesons,accessible through generalized parton distri-butions in their zero-skewness limit,are examined.These include electromagnetic and gravitational form fact...Several aspects of the internal structure of pseudoscalar mesons,accessible through generalized parton distri-butions in their zero-skewness limit,are examined.These include electromagnetic and gravitational form factors related to charge and mass densities;and distributions in the impact parameter space.To this end,we employ an algebraically viable framework that is based upon the valence-quark generalized parton distribution expressed explicitly in terms of the associated distribution function and a profile function that governs the off-forward dynamics.The predominantly analytical nature of this scheme yields several algebraic results and relations while also facilitating the exploration of insightful limiting cases.With a suitable input distribution function,guided either by experiment or theory,and with an appropriate choice of the profile function,it is possible to provide testable predictions for spatial distributions of valence quarks inside pseudoscalar mesons.When comparison is possible,these predictions align well with existing experimental data as well as the findings of reliable theoretical approaches and lattice QCD.展开更多
Electrocatalytic C–N coupling technology offers a promising route for green and sustainable urea synthesis.However,this route faces challenges of low urea yield and Faradaic efficiency due to the high dissociation en...Electrocatalytic C–N coupling technology offers a promising route for green and sustainable urea synthesis.However,this route faces challenges of low urea yield and Faradaic efficiency due to the high dissociation energy of atomic bonds in reactants,complex reaction intermediates,high reaction energy barriers,and competing side reactions.As C–N coupling involves the synergistic action of two or more active sites,it is crucial to develop efficient multi-active-site catalysts to address these challenges.This review analyzes the reaction mechanisms of electrocatalytic C–N coupling for urea synthesis and summarizes effective strategies to achieve multi-active-site catalysts,including heteroatom doping,defect engineering,heterojunctions,and diatomic catalysts.Furthermore,based on this analysis,we propose the universal design principles for high-efficiency multi-activesite catalysts.展开更多
Background Recombinant erythropoietin(rEPO)is commonly used in therapy but may be abused in sports to enhance endurance.In doping analysis,rEPO can be detected in human urine or blood samples at picogram(pg)levels bas...Background Recombinant erythropoietin(rEPO)is commonly used in therapy but may be abused in sports to enhance endurance.In doping analysis,rEPO can be detected in human urine or blood samples at picogram(pg)levels based on its slightly higher molecular weight(MW)than that of endogenous EPO using western blotting(WB).However,a type of variant erythropoietin(VAR-EPO)encoded by the EPO c.577del variant has a similar MW to rEPO,and these 2 molecules cannot be distinguished using conventional analytical methods.A fit-for-purpose method needs to be developed immediately.Methods In this study,we introduced a reverse–normal immunopurification technique for sample pretreatment to remove VAR-EPO from samples to eliminate its interference with rEPO detection.Firstly,a rabbit monoclonal antibody(mAb)that can specifically recognize trace amounts of VAR-EPO with high affinity was generated.Then,using this antibody to enrich VAR-EPO,we developed reverse–normal immunopurification coupled with WB on the purpose of analyzing rEPO in urine and serum samples.Next,the method was fully validated and evaluated using blank samples,spiked samples and rEPO excreted samples.Finally,the identification criteria of rEPO was established.Results A specific anti-VAR mAb with high affinity was developed.Using it,we developed the doping analytical method for rEPO.Our method effectively detects and removes VAR-EPO,enabling accurate rEPO detection.Conclusion A method has already been applied for rEPO confirmation in routine doping analyses.展开更多
As a representative of wide-bandgap semiconductors,wurtzite gallium nitride(GaN)has been widely utilized in highpower devices due to its high breakdown voltage and low specific on-resistance.Accurate prediction of wur...As a representative of wide-bandgap semiconductors,wurtzite gallium nitride(GaN)has been widely utilized in highpower devices due to its high breakdown voltage and low specific on-resistance.Accurate prediction of wurtzite GaN’s thermal conductivity is a prerequisite for designing effective thermal management systems for electronic applications.Machine learning-driven molecular dynamics simulation offers a promising approach to predicting the thermal conductivity of large-scale systems without requiring predefined parameters.However,these methods often underestimate the thermal conductivity of materials with inherently high thermal conductivity due to the large predicted force error compared with first-principles calculations,posing a critical challenge for their broader application.In this study,we successfully developed a neuroevolution potential for wurtzite GaN and accurately predicted its thermal conductivity,259±6 W/(m·K)at room temperature,achieving excellent agreement with reported experimental measurements.The hyperparameters of the neuroevolution potential(NEP)were optimized based on a systematic analysis of reproduced energy and force,structural features,and computational efficiency.Furthermore,a force error correction method was implemented,effectively reducing the error caused by the additional force noise in the Langevin thermostat by extrapolating to the zero-force error limit.This study provides valuable insights and holds significant implications for advancing efficient thermal management technologies in wide-bandgap semiconductor devices.展开更多
Understanding the structure-property relationship and the mechanisms by which catalysts promote polysulfide conversion is crucial for the rational design of room-temperature sodium-sulfur(RT Na-S)battery catalysts.Her...Understanding the structure-property relationship and the mechanisms by which catalysts promote polysulfide conversion is crucial for the rational design of room-temperature sodium-sulfur(RT Na-S)battery catalysts.Herein,we systematically investigate Fe-,Co-,and Ni-incorporated Mo_(2)C as catalysts for RT Na-S battery to elucidate the intrinsic correlation between the d band center of Mo in Mo_(2)C and its catalytic activity.Combining experimental and theoretical analysis revealed that Ni-substituted Mo_(2)C elevates the d band center while significantly reducing antibonding orbitals(π^(*))occupancy compared to Fe-substituted Mo_(2)C and Co-substituted Mo_(2)C counterparts.This electronic restruction enhances d-p hybridization at the Mo-S interface,which strengthens sodium polysulfides adsorption energy and enhances charge transfer,thereby steering sulfur redox pathways toward thermodynamically favorable configurations.Our findings elucidate the intricate interplay between the electronic structure and catalytic activity of Mo_(2)C,advancing a novel perspective for the rational design of RT Na-S battery catalysts through tailored modulation of antibonding orbital occupancy.展开更多
文摘Magnetic Resonance Imaging(MRI)has a pivotal role in medical image analysis,for its ability in supporting disease detection and diagnosis.Fuzzy C-Means(FCM)clustering is widely used for MRI segmentation due to its ability to handle image uncertainty.However,the latter still has countless limitations,including sensitivity to initialization,susceptibility to local optima,and high computational cost.To address these limitations,this study integrates Grey Wolf Optimization(GWO)with FCM to enhance cluster center selection,improving segmentation accuracy and robustness.Moreover,to further refine optimization,Fuzzy Entropy Clustering was utilized for its distinctive features from other traditional objective functions.Fuzzy entropy effectively quantifies uncertainty,leading to more well-defined clusters,improved noise robustness,and better preservation of anatomical structures in MRI images.Despite these advantages,the iterative nature of GWO and FCM introduces significant computational overhead,which restricts their applicability to high-resolution medical images.To overcome this bottleneck,we propose a Parallelized-GWO-based FCM(P-GWO-FCM)approach using GPU acceleration,where both GWO optimization and FCM updates(centroid computation and membership matrix updates)are parallelized.By concurrently executing these processes,our approach efficiently distributes the computational workload,significantly reducing execution time while maintaining high segmentation accuracy.The proposed parallel method,P-GWO-FCM,was evaluated on both simulated and clinical brain MR images,focusing on segmenting white matter,gray matter,and cerebrospinal fluid regions.The results indicate significant improvements in segmentation accuracy,achieving a Jaccard Similarity(JS)of 0.92,a Partition Coefficient Index(PCI)of 0.91,a Partition Entropy Index(PEI)of 0.25,and a Davies-Bouldin Index(DBI)of 0.30.Experimental comparisons demonstrate that P-GWO-FCM outperforms existing methods in both segmentation accuracy and computational efficiency,making it a promising solution for real-time medical image segmentation.
基金supported by the Slovenian Research Agency(research project NC-0001-Analysis of nuclear heating in a reactor,research core funding Reactor physics No.P2-0073,infrastructure program I0-0005)。
文摘Nuclear heating plays an important aspect in design and deployment of both fission and fusion reactors and experimental devices in terms of cooling requirements. Two experimental campaigns in the framework of a collaboration project between the French Atomic and Alternative Energy Commission(CEA) and Jožef Stefan Institute(JSI), Slovenia, have been performed at the JSI TRIGA reactor for the experimental assessment of nuclear heating in fission and fusion-relevant materials by the differential calorimetry technique, based on the CALMOS and CARMEN differential calorimeters, previously developed at CEA. The results of the first campaign performed at reactor powers between 100 and 250 kW have already been reported, highlighting some measurement difficulties. Therefore, the second campaign was performed at a lower reactor power of 30 kW to overcome these issues. Moreover, a computational analysis of the experiments was performed using the JSIR2S code package to calculate the nuclear heating levels. Both experiments and their reproduction by simulations are described in detail. We present a comparison of the previously reported measured nuclear heating values of the first campaign with the computational results, with consistent underestimation by simulations by 8–35%. We report the experimental and computational results for the second experimental campaign performed at a reactor power of 30 kW. The simulated heating values were in agreement with the measurements within the measured heating uncertainty, with simulated heating 2.7–11.3% lower than the experimental values.
基金funded by the National Natural Science Foundation of China(NNSFC)under Grant Numbers 42322408,42188101,and 42441809Additional support was provided by the Climbing Program of the National Space Science Center(NSSC,Grant No.E4PD3005)as well as the Specialized Research Fund for State Key Laboratories of China.
文摘A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-dimensional cusp boundary from a two-dimensional X-ray image because the detected X-ray signals will be integrated along the line of sight.In this work,a global magnetohydrodynamic code was used to simulate the X-ray images and photon count images,assuming an interplanetary magnetic field with a pure Bz component.The assumption of an elliptic cusp boundary at a given altitude was used to trace the equatorward and poleward boundaries of the cusp from a simulated X-ray image.The average discrepancy was less than 0.1 RE.To reduce the influence of instrument effects and cosmic X-ray backgrounds,image denoising was considered before applying the method above to SXI photon count images.The cusp boundaries were reasonably reconstructed from the noisy X-ray image.
基金supported by the National Natural Science Foundation of China(Grant No.52409151)the Programme of Shenzhen Key Laboratory of Green,Efficient and Intelligent Construction of Underground Metro Station(Programme No.ZDSYS20200923105200001)the Science and Technology Major Project of Xizang Autonomous Region of China(XZ202201ZD0003G).
文摘Substantial advancements have been achieved in Tunnel Boring Machine(TBM)technology and monitoring systems,yet the presence of missing data impedes accurate analysis and interpretation of TBM monitoring results.This study aims to investigate the issue of missing data in extensive TBM datasets.Through a comprehensive literature review,we analyze the mechanism of missing TBM data and compare different imputation methods,including statistical analysis and machine learning algorithms.We also examine the impact of various missing patterns and rates on the efficacy of these methods.Finally,we propose a dynamic interpolation strategy tailored for TBM engineering sites.The research results show that K-Nearest Neighbors(KNN)and Random Forest(RF)algorithms can achieve good interpolation results;As the missing rate increases,the interpolation effect of different methods will decrease;The interpolation effect of block missing is poor,followed by mixed missing,and the interpolation effect of sporadic missing is the best.On-site application results validate the proposed interpolation strategy's capability to achieve robust missing value interpolation effects,applicable in ML scenarios such as parameter optimization,attitude warning,and pressure prediction.These findings contribute to enhancing the efficiency of TBM missing data processing,offering more effective support for large-scale TBM monitoring datasets.
基金supported by a grant from the French Multiple Sclerosis Society(ARSEP,Grant Number:R20163LL)(to AMG)。
文摘Multiple sclerosis(MS)is the most common chronic disease of the central nervous system(CNS)in young adults and represents the first cause of severe handicap,originally non-traumatic(Oh et al.,2018).MS is chara cterized by the infiltration of auto reactive lymphocytes specific to myelin through the blood-brain barrier,which results in the appearance of inflammatory demyelinating lesions caused by the death of the central nervous system myelinating cells,oligodendrocytes(Oh et al.,2018).There is a prevalence sexual with a ratio of three times more affected women than men.
基金supported by LifeArc Philanthropic Fund(P2019-0004)LifeArc Pathfinder Award+7 种基金along with Wellcome Trust Seed Award(109626/Z/15/Z)FA PESP-UoB Strategic Collaboration FundBirmingham Fellowship(to SS)grants from Laboratoire d'Excellence Revive(Investissement d'AvenirANR-10-LABX-73)the Region lle-de-France via doctoral school Innovation Therapeutique,du Fondamentalàl'Appliqué(ED569)from Universite Paris-Saclay(to LA)Medical Research Council(MRC)Developmental Pathway Funding Scheme(DPFS)grant(MR/P007732/1)(to TB)supported by the Association Fran?aise contre les Myopathies(AFM-Téléthon)。
文摘Mitochondria and mitochondria-associated endoplasmic reticulum membrane in neurodegenerative diseases:Mitochondria generate most of the chemical energy needed to power the biochemical reactions of cells,and thus are often referred to as the"powerhouse"of the cell.Nevertheless,this organelle is also involved in a pleth,ora of different cellular functions such as calcium(Ca^(2+))homeostasis,apoptosis,oxidative stress,and several metabolic pathways including oxidative phosphorylation,tricarboxylic acid cycle,andβ-oxidation of fatty acids.
基金partially supported by RGC(No.17307420)supported by NSFC(No.12471077)。
文摘In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic solutions of some nonlinear ODEs together with some classical,19th-century results,can be turned into algorithms(thus avoiding ad hoc assumptions)which provide all(as opposed to some)solutions in a precise class.To illustrate these methods,we present some new such exact solutions,physically relevant.
基金financially supported by the National Natural Science Foundation of China(No.12262014).
文摘A gradient nanostructured layer was fabricated on the surface of TA15(Ti-6Al-2Zr-1Mo-1V)alloy(produced by selective laser melting)using severe shot peening(SSP).This study focuses on the evolution of the microstructure and the mechanism of grain refinement in TA15 titanium alloy during SSP treatment.Transmission electron microscopyand Rietveld refinement methods were employed.The residual stress and microhardness variations with depth were also characterized.The results show:(1)At the initial stage of deformation,plastic deformation is primarily accommodated through twinning and dislocation slip.(2)As the strain increases,twinning disappears,and dislocations interact to form tangles.Some dislocations annihilate and rearrange into subgrain boundaries,subdividing the original grains into subgrains.(3)With continued dislocation activity,the subgrain size decreases until nanocrystals are formed through the dynamic rotational recrystallization.SSP introduced compressive residual stress(CRS)in the near-surface layer of the material,with the maximum CRS of approximately−1141 MPa observed in the subsurface layer.It also induced work hardening,increasing the surface hardness to approximately 479 HV.However,the surface roughness increases,leading to a slight deterioration in surface quality.
文摘We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The free-electron contribution is described by the Maynard–Deutsch–Zimmerman formula,and the bound-electron contribution relies on the Bethe formula with corrections,in particular taking into account density and shell effects.The results of the bound-state computation using three different parametric potentials are investigated within the Garbet formalism for the mean excitation energy.The first parametric potential is due to Green,Sellin,and Zachor,the second one was proposed by Yunta,and the third one was introduced by Klapisch in the framework of atomic-structure computations.The results are compared with those of self-consistent average-atom calculations.This approach correctly bridges the limits of neutral and fully ionized matter.
基金financially supported by the National Natural Science Foundation of China(Nos.22306026 and 52371346)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(No.2023QNRC001)+3 种基金the Ecological Society of China(No.STQT2023C07)the Fundamental Research Funds for the Central Universities(Nos.2242024K40007 and 2242024RCB0058)the Start-up Research Fund of Southeast University(No.RF1028623141)Tang Scholar Program of Southeast University
文摘Transition metals have garnered significant attention for their roles in addressing energy shortages and environmental water pollution.Their multivalent states and unique electron transfer properties facilitate charge transfer in the conversion reaction,expedite energy conversion,and achieve low-energy water treatment.This review comprehensively explores the fundamental mechanisms and practical applications of transition metals in water treatment,including adsorption,photocatalysis,electrocatalysis,photoelectrocatalysis,and other technologies.The feasibility of water treatment using transition metal-based materials is demonstrated through theoretical studies on typical transition metals employed in these water treatment technologies while emphasizing the potential for optimizing material performance through strategies like structural design,defect engineering,crystal engineering,composite materials,surface modification,and atomic catalysts.In addition,the utilization of transition metal-based materials in practical wastewater treatment is comprehensively reviewed.Finally,the challenges and perspectives of transition metal-based materials in practical wastewater treatment are outlined,providing a theoretical foundation and guidance for future research and engineering advancements.
基金supported by the National Natural Science Foundation of China(No.12002290)。
文摘In the field of discretization-based meshfree/meshless methods,the improvements in the higher-order consistency,stability,and computational efficiency are of great concerns in computational science and numerical solutions to partial differential equations.Various alternative numerical methods of the finite particle method(FPM)frame have been extended from mathematical theories to numerical applications separately.As a comprehensive numerical scheme,this study suggests a unified resolved program for numerically investigating their accuracy,stability,consistency,computational efficiency,and practical applicability in industrial engineering contexts.The high-order finite particle method(HFPM)and corrected methods based on the multivariate Taylor series expansion are constructed and analyzed to investigate the whole applicability in different benchmarks of computational fluid dynamics.Specifically,four benchmarks are designed purposefully from statical exact solutions to multifaceted hydrodynamic tests,which possess different numerical performances on the particle consistency,numerical discretized forms,particle distributions,and transient time evolutional stabilities.This study offers a numerical reference for the current unified resolved program.
文摘Recent progress in the design and fabrication of thermal metasurfaces allows a broad control of the properties of light emission,including its polarization state.Stokes polarimetry is a key approach to accurately characterize partially polarized light.The quality of a Stokes polarimeter made of retarders and polarizers can be evaluated by use of metrics such as the equally weighted variance or the condition number of the matrix representing the polarimeter.Although specific instrument configurations are used to maximize polarimeter performance at a given wavelength,such optimal solutions are not spectrally robust because of the wave-length dependence of retardance.This becomes an issue in characterizing broadband thermal sources in the infrared.We report a Stokes polarimeter making use of five polarization analysis states and consisting of two simple and common optical elements—a crystalline waveplate and a linear polarizer.We combine this setup with a Fourier transform infrared spectrometer to measure accurately in a single set of acqui-sitions without requiring any spectral filtering,and to measure the polarization state with accuracy over a broad range of wavelengths.Such a Stokes polarimeter allows for close to optimal noise in the data reduc-tion process in the mid-wave infrared spectral range from 2.5 to 5μm.
文摘In this paper, we study the stability of a class of conformable fractional-order systems using the Lyapunov function. We assume that the nonlinear part of the system satisfies the one-sided Lipschitz condition and the quadratic inner-bounded condition. We provide some sufficient conditions that ensure the asymptotic stability of the system. Furthermore, we present the construction of a feedback stabilizing controller for conformable fractional bilinear systems.
基金supported by the Spanish MICINN grant PID2022-140440NB-C22the regional Andalusian project P18-FR-5057+3 种基金the Coordinación de la Investigación Científica of the Universidad Michoacana de San Nicolás de Hidalgo,Morelia,Mexico,Grant No.4.10the Consejo Nacional de Humanidades,Ciencias y Tecnologías,Mexico,project CBF2023-2024-3544the Beatriz-Galindo support during his current scientific stay at the University of Huelva,Huelva,Spainthe Chair d'excellence within the program d'Alembert supporting a visiting professorship in the Universitéde Paris-Saclay,France。
文摘Several aspects of the internal structure of pseudoscalar mesons,accessible through generalized parton distri-butions in their zero-skewness limit,are examined.These include electromagnetic and gravitational form factors related to charge and mass densities;and distributions in the impact parameter space.To this end,we employ an algebraically viable framework that is based upon the valence-quark generalized parton distribution expressed explicitly in terms of the associated distribution function and a profile function that governs the off-forward dynamics.The predominantly analytical nature of this scheme yields several algebraic results and relations while also facilitating the exploration of insightful limiting cases.With a suitable input distribution function,guided either by experiment or theory,and with an appropriate choice of the profile function,it is possible to provide testable predictions for spatial distributions of valence quarks inside pseudoscalar mesons.When comparison is possible,these predictions align well with existing experimental data as well as the findings of reliable theoretical approaches and lattice QCD.
基金supported by Foshan Xianhu Laboratory Project(No.XHD2024–31000000–06)Guangdong Basic and Applied Basic Research Foundation(Nos.2024A1515140005,2024B1515120017)National Natural Science Foundation of China(No.22308070).
文摘Electrocatalytic C–N coupling technology offers a promising route for green and sustainable urea synthesis.However,this route faces challenges of low urea yield and Faradaic efficiency due to the high dissociation energy of atomic bonds in reactants,complex reaction intermediates,high reaction energy barriers,and competing side reactions.As C–N coupling involves the synergistic action of two or more active sites,it is crucial to develop efficient multi-active-site catalysts to address these challenges.This review analyzes the reaction mechanisms of electrocatalytic C–N coupling for urea synthesis and summarizes effective strategies to achieve multi-active-site catalysts,including heteroatom doping,defect engineering,heterojunctions,and diatomic catalysts.Furthermore,based on this analysis,we propose the universal design principles for high-efficiency multi-activesite catalysts.
基金WADA and Beijing Sport University for funding under grant numbers 22B06XZ and 2022YB011
文摘Background Recombinant erythropoietin(rEPO)is commonly used in therapy but may be abused in sports to enhance endurance.In doping analysis,rEPO can be detected in human urine or blood samples at picogram(pg)levels based on its slightly higher molecular weight(MW)than that of endogenous EPO using western blotting(WB).However,a type of variant erythropoietin(VAR-EPO)encoded by the EPO c.577del variant has a similar MW to rEPO,and these 2 molecules cannot be distinguished using conventional analytical methods.A fit-for-purpose method needs to be developed immediately.Methods In this study,we introduced a reverse–normal immunopurification technique for sample pretreatment to remove VAR-EPO from samples to eliminate its interference with rEPO detection.Firstly,a rabbit monoclonal antibody(mAb)that can specifically recognize trace amounts of VAR-EPO with high affinity was generated.Then,using this antibody to enrich VAR-EPO,we developed reverse–normal immunopurification coupled with WB on the purpose of analyzing rEPO in urine and serum samples.Next,the method was fully validated and evaluated using blank samples,spiked samples and rEPO excreted samples.Finally,the identification criteria of rEPO was established.Results A specific anti-VAR mAb with high affinity was developed.Using it,we developed the doping analytical method for rEPO.Our method effectively detects and removes VAR-EPO,enabling accurate rEPO detection.Conclusion A method has already been applied for rEPO confirmation in routine doping analyses.
基金supported by the National Natural Science Foundation of China(Grant Nos.52376063 and 52306116)the Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology Prevention Fund(Grant No.2022-K03)the China Postdoctoral Science Foundation(Grant No.2023MD744223).
文摘As a representative of wide-bandgap semiconductors,wurtzite gallium nitride(GaN)has been widely utilized in highpower devices due to its high breakdown voltage and low specific on-resistance.Accurate prediction of wurtzite GaN’s thermal conductivity is a prerequisite for designing effective thermal management systems for electronic applications.Machine learning-driven molecular dynamics simulation offers a promising approach to predicting the thermal conductivity of large-scale systems without requiring predefined parameters.However,these methods often underestimate the thermal conductivity of materials with inherently high thermal conductivity due to the large predicted force error compared with first-principles calculations,posing a critical challenge for their broader application.In this study,we successfully developed a neuroevolution potential for wurtzite GaN and accurately predicted its thermal conductivity,259±6 W/(m·K)at room temperature,achieving excellent agreement with reported experimental measurements.The hyperparameters of the neuroevolution potential(NEP)were optimized based on a systematic analysis of reproduced energy and force,structural features,and computational efficiency.Furthermore,a force error correction method was implemented,effectively reducing the error caused by the additional force noise in the Langevin thermostat by extrapolating to the zero-force error limit.This study provides valuable insights and holds significant implications for advancing efficient thermal management technologies in wide-bandgap semiconductor devices.
基金supported by the National Natural Science Foundation of China(No.52372224 and 52072299)the Major Project of Shaanxi Coal Joint Fund of Shaanxi.Provincial Science and Technology Department(No.2019JLZ-07)。
文摘Understanding the structure-property relationship and the mechanisms by which catalysts promote polysulfide conversion is crucial for the rational design of room-temperature sodium-sulfur(RT Na-S)battery catalysts.Herein,we systematically investigate Fe-,Co-,and Ni-incorporated Mo_(2)C as catalysts for RT Na-S battery to elucidate the intrinsic correlation between the d band center of Mo in Mo_(2)C and its catalytic activity.Combining experimental and theoretical analysis revealed that Ni-substituted Mo_(2)C elevates the d band center while significantly reducing antibonding orbitals(π^(*))occupancy compared to Fe-substituted Mo_(2)C and Co-substituted Mo_(2)C counterparts.This electronic restruction enhances d-p hybridization at the Mo-S interface,which strengthens sodium polysulfides adsorption energy and enhances charge transfer,thereby steering sulfur redox pathways toward thermodynamically favorable configurations.Our findings elucidate the intricate interplay between the electronic structure and catalytic activity of Mo_(2)C,advancing a novel perspective for the rational design of RT Na-S battery catalysts through tailored modulation of antibonding orbital occupancy.
