This paper is concerned with certain multilinear commutators of BMO functions and multilinear singular integral operators with non-smooth kernels. By the sharp maximal functions estimates, the weighted norm inequaliti...This paper is concerned with certain multilinear commutators of BMO functions and multilinear singular integral operators with non-smooth kernels. By the sharp maximal functions estimates, the weighted norm inequalities for this kind of commutators are established.展开更多
This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators o...This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators on the weighted Lebesgue spaces, which extend and generalize some previous results, are obtained.展开更多
In this paper, we establish the boundedness of commutators of singular integral operators with non-smooth kernels on weighted Lipschitz spaces Lipβ,ω. The condition on the kernel in this paper is weaker than the usu...In this paper, we establish the boundedness of commutators of singular integral operators with non-smooth kernels on weighted Lipschitz spaces Lipβ,ω. The condition on the kernel in this paper is weaker than the usual pointwise HSrmander condition.展开更多
Let T1 be a singular integral with non-smooth kernel or ±I, let T2 and T4 be the linear operators and let T3 = ± I. Denote the Toeplitz type operator by Tb = T1M^b Ia T2 ＋ T3IaMbT4,where M^bf = bf, and Ib i...Let T1 be a singular integral with non-smooth kernel or ±I, let T2 and T4 be the linear operators and let T3 = ± I. Denote the Toeplitz type operator by Tb = T1M^b Ia T2 ＋ T3IaMbT4,where M^bf = bf, and Ib is the fractional integral operator. In this paper, we investigate the boundedness of the operator Tb on the weighted Morrey space when b belongs to the weighted BMO space.展开更多
Let T be a singular integral operator bounded on Lp(Rn) for some p, 1 < p < ∞. The authors give a sufficient condition on the kernel of T so that when b ∈BMO, the commutator [b,T](f) = T(bf) - bT(f) is bounded...Let T be a singular integral operator bounded on Lp(Rn) for some p, 1 < p < ∞. The authors give a sufficient condition on the kernel of T so that when b ∈BMO, the commutator [b,T](f) = T(bf) - bT(f) is bounded on the space Lp for all p, 1 < p < ∞. The condition of this paper is weaker than the usual pointwise Hormander condition.展开更多
In this article we obtain weighted norm estimates for multilinear singular integrals with non-smooth kernels and the boundedness of certain multilinear commutators by making use of a sharp maximal function.
Significant advancements have been achieved in the field of Single Image Super-Resolution(SISR)through the utilization of Convolutional Neural Networks(CNNs)to attain state-of-the-art performance.Recent efforts have e...Significant advancements have been achieved in the field of Single Image Super-Resolution(SISR)through the utilization of Convolutional Neural Networks(CNNs)to attain state-of-the-art performance.Recent efforts have explored the incorporation of Transformers to augment network performance in SISR.However,the high computational cost of Transformers makes them less suitable for deployment on lightweight devices.Moreover,the majority of enhancements for CNNs rely predominantly on small spatial convolutions,thereby neglecting the potential advantages of large kernel convolution.In this paper,the authors propose a Multi-Perception Large Kernel convNet(MPLKN)which delves into the exploration of large kernel convolution.Specifically,the authors have architected a Multi-Perception Large Kernel(MPLK)module aimed at extracting multi-scale features and employ a stepwise feature fusion strategy to seamlessly integrate these features.In addition,to enhance the network's capacity for nonlinear spatial information processing,the authors have designed a Spatial-Channel Gated Feed-forward Network(SCGFN)that is capable of adapting to feature interactions across both spatial and channel dimensions.Experimental results demonstrate that MPLKN outperforms other lightweight image super-resolution models while maintaining a minimal number of parameters and FLOPs.展开更多
The harmonic balance method(HBM)has been widely applied to get the periodic solution of nonlinear systems,however,its convergence rate as well as computation efficiency is dramatically degraded when the system is high...The harmonic balance method(HBM)has been widely applied to get the periodic solution of nonlinear systems,however,its convergence rate as well as computation efficiency is dramatically degraded when the system is highly non-smooth,e.g.,discontinuous.In order to accelerate the convergence,an enriched HBM is developed in this paper where the non-smooth Bernoulli bases are additionally introduced to enrich the conventional Fourier bases.The basic idea behind is that the convergence rate of the HB solution,as a truncated Fourier series,can be improved if the smoothness of the solution becomes finer.Along this line,using non-smooth Bernoulli bases can compensate the highly non-smooth part of the solution and then,the smoothness of the residual part for Fourier approximation is improved so as to achieve accelerated convergence.Numerical examples are conducted on systems with non-smooth restoring and/or external forces.The results confirm that the proposed enriched HBM indeed increases the convergence rate and the increase becomes more significant if more non-smooth bases are used.展开更多
LetΩbe homogeneous of degree zero,integrable on S^(d−1) and have vanishing moment of order one,a be a function on R^(d) such that ∇a∈L^(∞)(R^(d)).Let T*_(Ω,a) be the maximaloperator associated with the d-dimensional...LetΩbe homogeneous of degree zero,integrable on S^(d−1) and have vanishing moment of order one,a be a function on R^(d) such that ∇a∈L^(∞)(R^(d)).Let T*_(Ω,a) be the maximaloperator associated with the d-dimensional Calder´on commutator defined by T*_(Ωa)f(x):=sup_(ε>0)|∫_(|x-y|>ε)^Ω(x-y)/|x-y|^(d+1)(a(x)-a(y))f(y)dy.In this paper,the authors establish bilinear sparse domination for T*_(Ω,a) under the assumption Ω∈L∞(Sd−1).As applications,some quantitative weighted bounds for T*_(Ω,a) are obtained.展开更多
The high-speed development of space defense technology demands a high state estimation capacity for spacecraft tracking methods.However,reentry flight is accompanied by complex flight environments,which brings to the ...The high-speed development of space defense technology demands a high state estimation capacity for spacecraft tracking methods.However,reentry flight is accompanied by complex flight environments,which brings to the uncertain,complex,and strongly coupled non-Gaussian detection noise.As a result,there are several intractable considerations on the problem of state estimation tasks corrupted by complex non-Gaussian outliers for non-linear dynamics systems in practical application.To address these issues,a new iterated rational quadratic(RQ)kernel high-order unscented Kalman filtering(IRQHUKF)algorithm via capturing the statistics to break through the limitations of the Gaussian assumption is proposed.Firstly,the characteristic analysis of the RQ kernel is investigated in detail,which is the first attempt to carry out an exploration of the heavy-tailed characteristic and the ability on capturing highorder moments of the RQ kernel.Subsequently,the RQ kernel method is first introduced into the UKF algorithm as an error optimization criterion,termed the iterated RQ kernel-UKF(RQ-UKF)algorithm by derived analytically,which not only retains the high-order moments propagation process but also enhances the approximation capacity in the non-Gaussian noise problem for its ability in capturing highorder moments and heavy-tailed characteristics.Meanwhile,to tackle the limitations of the Gaussian distribution assumption in the linearization process of the non-linear systems,the high-order Sigma Points(SP)as a subsidiary role in propagating the state high-order statistics is devised by the moments matching method to improve the RQ-UKF.Finally,to further improve the flexibility of the IRQ-HUKF algorithm in practical application,an adaptive kernel parameter is derived analytically grounded in the Kullback-Leibler divergence(KLD)method and parametric sensitivity analysis of the RQ kernel.The simulation results demonstrate that the novel IRQ-HUKF algorithm is more robust and outperforms the existing advanced UKF with respect to the kernel method in reentry vehicle tracking scenarios under various noise environments.展开更多
Transcription factors play critical roles in the regulation of gene expression during maize kernel development.The maize endosperm,a large storage organ,accounting for nearly 90%of the dry weight of mature kernels,ser...Transcription factors play critical roles in the regulation of gene expression during maize kernel development.The maize endosperm,a large storage organ,accounting for nearly 90%of the dry weight of mature kernels,serves as the primary site for starch storage.In this study,we identify an endosperm-specific EREB gene,ZmEREB167,which encodes a nucleus-localized EREB protein.Knockout of ZmEREB167 significantly increases kernel size and weight,as well as starch and protein content,compared with the wild type.In situ hybridization experiments show that ZmEREB167 is highly expressed in the BETL as well as PED regions of maize kernels.Dual-luciferase assays show that ZmEREB167 exhibits transcriptionally repressor activity in maize protoplasts.Transcriptome analysis reveals that a large number of genes are up-regulated in the Zmereb167-C1 mutant compared with the wild type,including key genetic factors such as ZmMRP-1 and ZmMN1,as well as multiple transporters involved in maize endosperm development.Integration of RNA-seq and ChIP-seq results identify 68 target genes modulated by ZmEREB167.We find that ZmEREB167 directly targets OPAQUE2,ZmNRT1.1,ZmIAA12,ZmIAA19,and ZmbZIP20,repressing their expressions.Our study demonstrates that ZmEREB167 functions as a negative regulator in maize endosperm development and affects starch accumulation and kernel size.展开更多
Current research on wind energy piezoelectric energy harvesters(PEHs)mainly focuses on tandem smooth cylinder energy harvesters;however,the traditional tandem smooth cylinder energy harvester has low voltage output an...Current research on wind energy piezoelectric energy harvesters(PEHs)mainly focuses on tandem smooth cylinder energy harvesters;however,the traditional tandem smooth cylinder energy harvester has low voltage output and narrow energy harvest bandwidth.In this study,a D-type bionic fin is designed and installed on a smooth cylindrical surface to improve its performance.The influence of the spacing ratio on the amplitude and voltage of PEHs with D-type bionic fins added under elastic interference was investigated through wind tunnel tests.Three installation positions were designed:only installed upstream,only installed downstream,and not installed upstream and downstream(BARE).It was found that the maximum displacement of the upstream PEH(UPEH)was not apparently affected by the D-type bionic fin.Contrastingly,the fin changed the maximum amplitude from a small to a large spacing ratio for the downstream PEH(DPEH).D-type bionic fin can enhance energy harvest performance by coupling“coupled vortex-induced vibration”and wake induced galloping,increasing the surface velocity of PEHs and expanding the bandwidth of the voltage harvested by the PEHs.Analysis of the power under the experimental wind speed showed that installing D-type fins in the PEHs can increase the output power of the upstream and downstream PEHs by 392.28%and 13%,respectively,compared with that of the BARE-PEH.Additionally,computational fluid dynamics was used to analyze the flow pattern,wake structure,and lift coefficient of the PEHs,and to explain why the upstream D-type bionic fin installation has an impact on the harvest performance of the upstream and downstream PEHs at a spacing ratio of 1.5.This study provides an efficient and simple scheme for designing wind PEHs.展开更多
We present and explore a new shock-capturing particle hydrodynamics approach.Our starting point is a commonly used discretization of smoothed particle hydrodynamics.We enhance this discretization with Roe’s approx-im...We present and explore a new shock-capturing particle hydrodynamics approach.Our starting point is a commonly used discretization of smoothed particle hydrodynamics.We enhance this discretization with Roe’s approx-imate Riemann solver,we identify its dissipative terms,and in these terms,we use slope-limited linear reconstruction.All gradients needed for our method are calculated with linearly reproducing kernels that are constructed to enforce the two lowest-order consistency relations.We scrutinize our reproducing kernel implementation carefully on a“glass-like”particle distribution,and we find that constant and linear functions are recovered to machine precision.We probe our method in a series of challenging 3D benchmark problems ranging from shocks over instabilities to Schulz-Rinne-type vorticity-creating shocks.All of our simulations show excellent agreement with analytic/reference solutions.展开更多
Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for ...Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for maize resistance to Ustilago maydis and for overall plant development.In this study,we explored the role of ZmADT2 in maize kernel development.The mmsu mutant,a dysfunctional ZmADT2 variant,exhibits delayed embryo and endosperm development,along with deficiencies in carbohydrate and protein storage.Transcriptome analysis revealed differential expression of many kernel compartment-specific genes between mmsu and wild-type(WT)kernels,with impaired nutrient accumulation and auxin signaling pathway in the mmsu endosperm.Compared to WT,ZmADT2 mutation led to reduced auxin levels and smaller endosperm cell size.Exogenous auxin rescued the small kernel phenotype of mmsu.Additionally,auxin distribution was reduced in the basal endosperm transfer layer(BETL),causing defects in its development and function,including reduced transfer cell elongation,cell wall ingrowth and nutrient uptake.These findings suggest that ZmADT2 mediated mediates an auxin signaling pathway that is essential for maize kernel development.展开更多
In recent years,deep learning has been introduced into the field of Single-pixel imaging(SPI),garnering significant attention.However,conventional networks still exhibit limitations in preserving image details.To addr...In recent years,deep learning has been introduced into the field of Single-pixel imaging(SPI),garnering significant attention.However,conventional networks still exhibit limitations in preserving image details.To address this issue,we integrate Large Kernel Convolution(LKconv)into the U-Net framework,proposing an enhanced network structure named U-LKconv network,which significantly enhances the capability to recover image details even under low sampling conditions.展开更多
Palm kernel cake(PKC),a major by-product of the palm oil industry,is rich in non-starch polysaccharides.In this study,two polysaccharide fractions,precipitated with acetic acid(PPA)and ethanol(PPE),respectively,were e...Palm kernel cake(PKC),a major by-product of the palm oil industry,is rich in non-starch polysaccharides.In this study,two polysaccharide fractions,precipitated with acetic acid(PPA)and ethanol(PPE),respectively,were extracted from PKC using a 2 mol/L NaOH solution.The molecular weight,sugar composition,structural characteristics,morphology,antioxidant activity,as well as in vitro stimulated digestion were investigated in detail.The results revealed that due to its poor solubility of PPA in water,the detected molecular weight of PPA was only 2040 g/mol,which was significantly lower than that of PPE(65,300 g/mol).Although PPA and PPE had a similar sugar composition with varying contents,mannose was the predominant monosaccharide in both,accounting for 87.71%and 60.40%,respectively.Both PPA and PPE were primarily composed of crystalline mannan,consisting of mannopyranosyl units linked by(1→4)-β-glycosidic bonds,along with a small amount of lignin.PPA possibly contained a higher proportion of crystalline mannan,whereas PPE had a larger amount of arabinoxylan and galactomannan.Atomic force microscope revealed a stacked morphology for both PPA and PPE.PPA exhibited a higher scavenging rate against DPPH•and ABTS^(+)•but a weaker HO•scavenging activity and reducing power compared with PPE.Within the polysaccharide concentration range of 0.5-5.0 mg/mL,PPA and PPB demonstrated the strongest scavenging activity against ABTS^(+)•,with the highest scavenging rates exceeding 91%.However,PPA and PPB exhibited the weakest scavenging activity against HO•,with their highest HO•scavenging rates reaching only 44.91%and 55.86%,respectively.The antioxidant activities of both PPA and PPE were weaker than that of ascorbic acid.PPA remained almost stable in the in vitro simulated saliva fluid,while PPE exhibited weaker resistance to it.Both PPA and PPE exhibited weak resistance to the in vitro simulated gastric digestion fluids,but remained relatively stable in the in vitro simulated small-intestinal digestion fluid.The differences in physicochemical properties between PPA and PPE likely played an important role in their distinct biological activities.These findings suggest potential utilization of PKC in exploring dietary polysaccharides with favorable antioxidant activity and unique digestive characteristics.展开更多
Mitochondria are semi-autonomous organelles present in eukaryotic cells,containing their own genome and transcriptional machinery.However,their functions are intricately linked to proteins encoded by the nuclear genom...Mitochondria are semi-autonomous organelles present in eukaryotic cells,containing their own genome and transcriptional machinery.However,their functions are intricately linked to proteins encoded by the nuclear genome.Mitochondrial transcription termination factors(mTERFs)are nucleic acid-binding proteins involved in RNA splicing and transcription termination within plant mitochondria and chloroplasts.Despite their recognized importance,the specific roles of mTERF proteins in maize remain largely unexplored.Here,we clone and functionally characterize the maize mTERF18 gene.Our findings reveal that mTERF18 mutations lead to severely undifferentiated embryos,resulting in abortive phenotypes.Early kernel exhibits abnormal basal endosperm transfer layer and a significant reduction in both starch and protein accumulation in mterf18.We identify the mTERF18 gene through mapping-based cloning and validate this gene through allelic tests.mTERF18 is widely expressed across various maize tissues and encodes a highly conserved mitochondrial protein.Transcriptome data reveal that mTERF18 mutations disrupt transcriptional termination of the nad6 gene,leading to undetectable levels of Nad6 protein and reduced complex I assembly and activity.Furthermore,transmission electron microscopy observation of mterf18 endosperm uncover severe mitochondrial defects.Collectively,these findings highlight the critical role of mTERF18 in mitochondrial gene transcription termination and its pivotal impact on maize kernel development.展开更多
Seed maturation is a critical development transition and it largely affects the final yield and quality of crops.Abscisic acid(ABA)-activated sucrose-non-fermentation kinase subfamily 2(SnRK2s)constitute a well-known ...Seed maturation is a critical development transition and it largely affects the final yield and quality of crops.Abscisic acid(ABA)-activated sucrose-non-fermentation kinase subfamily 2(SnRK2s)constitute a well-known regulatory network that modulate seed maturation in Arabidopsis;however,the underlying genetic and regulatory mechanisms in cereal crops remain largely unknown.Here,we found that ABA levels exhibited two distinct peaks during kernel development in maize,corresponding to the lag and maturation phase,respectively.Integrated transcriptome and proteome profiling of kernels treated with exogenous ABA at the pre-maturation stage suggested that the second peak of ABA acts as a trigger for kernel maturation program.Knockout of ZmSnRK2s demonstrated that subclassⅢZmSnRK2s are required for kernel maturation in maize,and the loss-of-function of subclassⅢZmSnRK2s showed a disruption in kernel dehydration and dormancy.We identified a conserved ABA–SnRK2–b ZIP signaling pathway mediating this process in maize.Additionally,ZmSnRK2.10 overexpression accelerates kernel dehydration during maturity,achieving reduced kernel moisture content(KMC)at physiological maturity(PM).Overall,our findings establish ABA-activated SnRK2s as central regulators of kernel maturation in maize and provide valuable genetic resources for breeding maize varieties with low moisture content at harvest.展开更多
As one of the most serious geological disasters in deep underground engineering,rockburst has caused a large number of casualties.However,because of the complex relationship between the inducing factors and rockburst ...As one of the most serious geological disasters in deep underground engineering,rockburst has caused a large number of casualties.However,because of the complex relationship between the inducing factors and rockburst intensity,the problem of rockburst intensity prediction has not been well solved until now.In this study,we collect 292 sets of rockburst data including eight parameters,such as the maximum tangential stress of the surrounding rock σ_(θ),the uniaxial compressive strength of the rockσc,the uniaxial tensile strength of the rock σ_(t),and the strain energy storage index W_(et),etc.from more than 20 underground projects as training sets and establish two new rockburst prediction models based on the kernel extreme learning machine(KELM)combined with the genetic algorithm(KELM-GA)and cross-entropy method(KELM-CEM).To further verify the effect of the two models,ten sets of rockburst data from Shuangjiangkou Hydropower Station are selected for analysis and the results show that new models are more accurate compared with five traditional empirical criteria,especially the model based on KELM-CEM which has the accuracy rate of 90%.Meanwhile,the results of 10 consecutive runs of the model based on KELM-CEM are almost the same,meaning that the model has good stability and reliability for engineering applications.展开更多
This paper considers the following Marcinkiewicz type integrals■which can be regarded as an extension of the classical Marcinkiewicz integral po introduced by Stein in[Trans Amer Math Soc,88(1958):159-172],where Ω i...This paper considers the following Marcinkiewicz type integrals■which can be regarded as an extension of the classical Marcinkiewicz integral po introduced by Stein in[Trans Amer Math Soc,88(1958):159-172],where Ω is a homogeneous function of degree zero on R^(n)with mean value zero in the unit sphere S^(n-1),Under the assumption that Ω∈L^(∞)(S^(n-1)),the authors establish the L^(q)-estimate and weak(1,1)type estimate as well as the corresponding weighted estimates for po.s with 1<q<∞ and 0<β(q-1)n/q.Moreover,the bounds do not depend on β and the strong(q,q)type and weak(1,1)type estimates for the classical Marcinkiewicz integral po can be recovered from the above estimates of μΩ,β whenβ→0.展开更多
基金Supported by the National Natural Science Foundation of China (10771054, 10771221, 11071200)the Youth Foundation of Wuyi University (No. xq0930)
文摘This paper is concerned with certain multilinear commutators of BMO functions and multilinear singular integral operators with non-smooth kernels. By the sharp maximal functions estimates, the weighted norm inequalities for this kind of commutators are established.
基金Supported by the National Natural Science Foundation of China (10771054,11071200)the NFS of Fujian Province of China (No. 2010J01013)
文摘This paper is devoted to studying the commutators of the multilinear singular integral operators with the non-smooth kernels and the weighted Lipschitz functions. Some mapping properties for two types of commutators on the weighted Lebesgue spaces, which extend and generalize some previous results, are obtained.
文摘In this paper, we establish the boundedness of commutators of singular integral operators with non-smooth kernels on weighted Lipschitz spaces Lipβ,ω. The condition on the kernel in this paper is weaker than the usual pointwise HSrmander condition.
文摘Let T1 be a singular integral with non-smooth kernel or ±I, let T2 and T4 be the linear operators and let T3 = ± I. Denote the Toeplitz type operator by Tb = T1M^b Ia T2 ＋ T3IaMbT4,where M^bf = bf, and Ib is the fractional integral operator. In this paper, we investigate the boundedness of the operator Tb on the weighted Morrey space when b belongs to the weighted BMO space.
文摘Let T be a singular integral operator bounded on Lp(Rn) for some p, 1 < p < ∞. The authors give a sufficient condition on the kernel of T so that when b ∈BMO, the commutator [b,T](f) = T(bf) - bT(f) is bounded on the space Lp for all p, 1 < p < ∞. The condition of this paper is weaker than the usual pointwise Hormander condition.
文摘In this article we obtain weighted norm estimates for multilinear singular integrals with non-smooth kernels and the boundedness of certain multilinear commutators by making use of a sharp maximal function.
文摘Significant advancements have been achieved in the field of Single Image Super-Resolution(SISR)through the utilization of Convolutional Neural Networks(CNNs)to attain state-of-the-art performance.Recent efforts have explored the incorporation of Transformers to augment network performance in SISR.However,the high computational cost of Transformers makes them less suitable for deployment on lightweight devices.Moreover,the majority of enhancements for CNNs rely predominantly on small spatial convolutions,thereby neglecting the potential advantages of large kernel convolution.In this paper,the authors propose a Multi-Perception Large Kernel convNet(MPLKN)which delves into the exploration of large kernel convolution.Specifically,the authors have architected a Multi-Perception Large Kernel(MPLK)module aimed at extracting multi-scale features and employ a stepwise feature fusion strategy to seamlessly integrate these features.In addition,to enhance the network's capacity for nonlinear spatial information processing,the authors have designed a Spatial-Channel Gated Feed-forward Network(SCGFN)that is capable of adapting to feature interactions across both spatial and channel dimensions.Experimental results demonstrate that MPLKN outperforms other lightweight image super-resolution models while maintaining a minimal number of parameters and FLOPs.
基金supported by the National Natural Science Foundation of China (Grant No. 12372028)the National Key Research and Development Program of China (Grant No. 2020YFC2201101)the Guangdong Basic and Applied Basic Research Foundation (Grant No.2022A1515011809)。
文摘The harmonic balance method(HBM)has been widely applied to get the periodic solution of nonlinear systems,however,its convergence rate as well as computation efficiency is dramatically degraded when the system is highly non-smooth,e.g.,discontinuous.In order to accelerate the convergence,an enriched HBM is developed in this paper where the non-smooth Bernoulli bases are additionally introduced to enrich the conventional Fourier bases.The basic idea behind is that the convergence rate of the HB solution,as a truncated Fourier series,can be improved if the smoothness of the solution becomes finer.Along this line,using non-smooth Bernoulli bases can compensate the highly non-smooth part of the solution and then,the smoothness of the residual part for Fourier approximation is improved so as to achieve accelerated convergence.Numerical examples are conducted on systems with non-smooth restoring and/or external forces.The results confirm that the proposed enriched HBM indeed increases the convergence rate and the increase becomes more significant if more non-smooth bases are used.
文摘LetΩbe homogeneous of degree zero,integrable on S^(d−1) and have vanishing moment of order one,a be a function on R^(d) such that ∇a∈L^(∞)(R^(d)).Let T*_(Ω,a) be the maximaloperator associated with the d-dimensional Calder´on commutator defined by T*_(Ωa)f(x):=sup_(ε>0)|∫_(|x-y|>ε)^Ω(x-y)/|x-y|^(d+1)(a(x)-a(y))f(y)dy.In this paper,the authors establish bilinear sparse domination for T*_(Ω,a) under the assumption Ω∈L∞(Sd−1).As applications,some quantitative weighted bounds for T*_(Ω,a) are obtained.
基金supported by the National Natural Science Foundation of China under Grant No.12072090.
文摘The high-speed development of space defense technology demands a high state estimation capacity for spacecraft tracking methods.However,reentry flight is accompanied by complex flight environments,which brings to the uncertain,complex,and strongly coupled non-Gaussian detection noise.As a result,there are several intractable considerations on the problem of state estimation tasks corrupted by complex non-Gaussian outliers for non-linear dynamics systems in practical application.To address these issues,a new iterated rational quadratic(RQ)kernel high-order unscented Kalman filtering(IRQHUKF)algorithm via capturing the statistics to break through the limitations of the Gaussian assumption is proposed.Firstly,the characteristic analysis of the RQ kernel is investigated in detail,which is the first attempt to carry out an exploration of the heavy-tailed characteristic and the ability on capturing highorder moments of the RQ kernel.Subsequently,the RQ kernel method is first introduced into the UKF algorithm as an error optimization criterion,termed the iterated RQ kernel-UKF(RQ-UKF)algorithm by derived analytically,which not only retains the high-order moments propagation process but also enhances the approximation capacity in the non-Gaussian noise problem for its ability in capturing highorder moments and heavy-tailed characteristics.Meanwhile,to tackle the limitations of the Gaussian distribution assumption in the linearization process of the non-linear systems,the high-order Sigma Points(SP)as a subsidiary role in propagating the state high-order statistics is devised by the moments matching method to improve the RQ-UKF.Finally,to further improve the flexibility of the IRQ-HUKF algorithm in practical application,an adaptive kernel parameter is derived analytically grounded in the Kullback-Leibler divergence(KLD)method and parametric sensitivity analysis of the RQ kernel.The simulation results demonstrate that the novel IRQ-HUKF algorithm is more robust and outperforms the existing advanced UKF with respect to the kernel method in reentry vehicle tracking scenarios under various noise environments.
基金supported by STI 2030-Major Project(2023ZD04069)National Key Research and Development Program of China(2023YFD1202900)+3 种基金The National Science Fund for Distinguished Young Scholars(32425041)The“Breakthrough”Science and Technology Project of Tongliao(TL2024TW001)Science and Technology Demonstration Project of Shandong Province(2024SFGC0402)Pinduoduo-China Agricultural University Research Fund(PC2023A01004).
文摘Transcription factors play critical roles in the regulation of gene expression during maize kernel development.The maize endosperm,a large storage organ,accounting for nearly 90%of the dry weight of mature kernels,serves as the primary site for starch storage.In this study,we identify an endosperm-specific EREB gene,ZmEREB167,which encodes a nucleus-localized EREB protein.Knockout of ZmEREB167 significantly increases kernel size and weight,as well as starch and protein content,compared with the wild type.In situ hybridization experiments show that ZmEREB167 is highly expressed in the BETL as well as PED regions of maize kernels.Dual-luciferase assays show that ZmEREB167 exhibits transcriptionally repressor activity in maize protoplasts.Transcriptome analysis reveals that a large number of genes are up-regulated in the Zmereb167-C1 mutant compared with the wild type,including key genetic factors such as ZmMRP-1 and ZmMN1,as well as multiple transporters involved in maize endosperm development.Integration of RNA-seq and ChIP-seq results identify 68 target genes modulated by ZmEREB167.We find that ZmEREB167 directly targets OPAQUE2,ZmNRT1.1,ZmIAA12,ZmIAA19,and ZmbZIP20,repressing their expressions.Our study demonstrates that ZmEREB167 functions as a negative regulator in maize endosperm development and affects starch accumulation and kernel size.
基金Supported by National Natural Science Foundation of China(Grant No.21978202).
文摘Current research on wind energy piezoelectric energy harvesters(PEHs)mainly focuses on tandem smooth cylinder energy harvesters;however,the traditional tandem smooth cylinder energy harvester has low voltage output and narrow energy harvest bandwidth.In this study,a D-type bionic fin is designed and installed on a smooth cylindrical surface to improve its performance.The influence of the spacing ratio on the amplitude and voltage of PEHs with D-type bionic fins added under elastic interference was investigated through wind tunnel tests.Three installation positions were designed:only installed upstream,only installed downstream,and not installed upstream and downstream(BARE).It was found that the maximum displacement of the upstream PEH(UPEH)was not apparently affected by the D-type bionic fin.Contrastingly,the fin changed the maximum amplitude from a small to a large spacing ratio for the downstream PEH(DPEH).D-type bionic fin can enhance energy harvest performance by coupling“coupled vortex-induced vibration”and wake induced galloping,increasing the surface velocity of PEHs and expanding the bandwidth of the voltage harvested by the PEHs.Analysis of the power under the experimental wind speed showed that installing D-type fins in the PEHs can increase the output power of the upstream and downstream PEHs by 392.28%and 13%,respectively,compared with that of the BARE-PEH.Additionally,computational fluid dynamics was used to analyze the flow pattern,wake structure,and lift coefficient of the PEHs,and to explain why the upstream D-type bionic fin installation has an impact on the harvest performance of the upstream and downstream PEHs at a spacing ratio of 1.5.This study provides an efficient and simple scheme for designing wind PEHs.
基金supported by the Swedish Research Council(VR)under grant number 2020-05044by the research environment grant"Gravitational Radiation and Electromagnetic Astrophysical Transients"(GREAT)funded by the Swedish Research Council(VR)under Dnr 2016-06012+2 种基金by the Knut and Alice Wallenberg Foundation under grant Dnr.KAW 2019.0112by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany's Excellence Strategy-EXC 2121"Quantum Universe"-390833306by the European Research Council(ERC)Advanced Grant INSPIRATION under the European Union's Horizon 2020 Research and Innovation Programme(Grant agreement No.101053985).
文摘We present and explore a new shock-capturing particle hydrodynamics approach.Our starting point is a commonly used discretization of smoothed particle hydrodynamics.We enhance this discretization with Roe’s approx-imate Riemann solver,we identify its dissipative terms,and in these terms,we use slope-limited linear reconstruction.All gradients needed for our method are calculated with linearly reproducing kernels that are constructed to enforce the two lowest-order consistency relations.We scrutinize our reproducing kernel implementation carefully on a“glass-like”particle distribution,and we find that constant and linear functions are recovered to machine precision.We probe our method in a series of challenging 3D benchmark problems ranging from shocks over instabilities to Schulz-Rinne-type vorticity-creating shocks.All of our simulations show excellent agreement with analytic/reference solutions.
基金funded by the National Natural Science Foundation of China(32071921)Key R&D Program of Shandong Province,China(2021LZGC022)Taishan Scholars Project(ts201712024).
文摘Arogenate dehydratase(ADT)catalyzes the final step in phenylalanine synthesis and is crucial for plant development and metabolism.Previously,we demonstrated that the ADT/prephenate dehydratase ZmADT2 is essential for maize resistance to Ustilago maydis and for overall plant development.In this study,we explored the role of ZmADT2 in maize kernel development.The mmsu mutant,a dysfunctional ZmADT2 variant,exhibits delayed embryo and endosperm development,along with deficiencies in carbohydrate and protein storage.Transcriptome analysis revealed differential expression of many kernel compartment-specific genes between mmsu and wild-type(WT)kernels,with impaired nutrient accumulation and auxin signaling pathway in the mmsu endosperm.Compared to WT,ZmADT2 mutation led to reduced auxin levels and smaller endosperm cell size.Exogenous auxin rescued the small kernel phenotype of mmsu.Additionally,auxin distribution was reduced in the basal endosperm transfer layer(BETL),causing defects in its development and function,including reduced transfer cell elongation,cell wall ingrowth and nutrient uptake.These findings suggest that ZmADT2 mediated mediates an auxin signaling pathway that is essential for maize kernel development.
文摘In recent years,deep learning has been introduced into the field of Single-pixel imaging(SPI),garnering significant attention.However,conventional networks still exhibit limitations in preserving image details.To address this issue,we integrate Large Kernel Convolution(LKconv)into the U-Net framework,proposing an enhanced network structure named U-LKconv network,which significantly enhances the capability to recover image details even under low sampling conditions.
基金supported by the National Natural Science Foundation of China(No.22068025).
文摘Palm kernel cake(PKC),a major by-product of the palm oil industry,is rich in non-starch polysaccharides.In this study,two polysaccharide fractions,precipitated with acetic acid(PPA)and ethanol(PPE),respectively,were extracted from PKC using a 2 mol/L NaOH solution.The molecular weight,sugar composition,structural characteristics,morphology,antioxidant activity,as well as in vitro stimulated digestion were investigated in detail.The results revealed that due to its poor solubility of PPA in water,the detected molecular weight of PPA was only 2040 g/mol,which was significantly lower than that of PPE(65,300 g/mol).Although PPA and PPE had a similar sugar composition with varying contents,mannose was the predominant monosaccharide in both,accounting for 87.71%and 60.40%,respectively.Both PPA and PPE were primarily composed of crystalline mannan,consisting of mannopyranosyl units linked by(1→4)-β-glycosidic bonds,along with a small amount of lignin.PPA possibly contained a higher proportion of crystalline mannan,whereas PPE had a larger amount of arabinoxylan and galactomannan.Atomic force microscope revealed a stacked morphology for both PPA and PPE.PPA exhibited a higher scavenging rate against DPPH•and ABTS^(+)•but a weaker HO•scavenging activity and reducing power compared with PPE.Within the polysaccharide concentration range of 0.5-5.0 mg/mL,PPA and PPB demonstrated the strongest scavenging activity against ABTS^(+)•,with the highest scavenging rates exceeding 91%.However,PPA and PPB exhibited the weakest scavenging activity against HO•,with their highest HO•scavenging rates reaching only 44.91%and 55.86%,respectively.The antioxidant activities of both PPA and PPE were weaker than that of ascorbic acid.PPA remained almost stable in the in vitro simulated saliva fluid,while PPE exhibited weaker resistance to it.Both PPA and PPE exhibited weak resistance to the in vitro simulated gastric digestion fluids,but remained relatively stable in the in vitro simulated small-intestinal digestion fluid.The differences in physicochemical properties between PPA and PPE likely played an important role in their distinct biological activities.These findings suggest potential utilization of PKC in exploring dietary polysaccharides with favorable antioxidant activity and unique digestive characteristics.
基金supported by the National Key Research and Development Program of China(2021YFF1000304)the National Natural Science Foundation of China(32222060)Anhui Agricultural University(RC422404)to J.Y.
文摘Mitochondria are semi-autonomous organelles present in eukaryotic cells,containing their own genome and transcriptional machinery.However,their functions are intricately linked to proteins encoded by the nuclear genome.Mitochondrial transcription termination factors(mTERFs)are nucleic acid-binding proteins involved in RNA splicing and transcription termination within plant mitochondria and chloroplasts.Despite their recognized importance,the specific roles of mTERF proteins in maize remain largely unexplored.Here,we clone and functionally characterize the maize mTERF18 gene.Our findings reveal that mTERF18 mutations lead to severely undifferentiated embryos,resulting in abortive phenotypes.Early kernel exhibits abnormal basal endosperm transfer layer and a significant reduction in both starch and protein accumulation in mterf18.We identify the mTERF18 gene through mapping-based cloning and validate this gene through allelic tests.mTERF18 is widely expressed across various maize tissues and encodes a highly conserved mitochondrial protein.Transcriptome data reveal that mTERF18 mutations disrupt transcriptional termination of the nad6 gene,leading to undetectable levels of Nad6 protein and reduced complex I assembly and activity.Furthermore,transmission electron microscopy observation of mterf18 endosperm uncover severe mitochondrial defects.Collectively,these findings highlight the critical role of mTERF18 in mitochondrial gene transcription termination and its pivotal impact on maize kernel development.
基金supported by the National Natural Science Foundation of China(32201696)the Natural Science Foundation of Sichuan Province(23NSFSC4071)。
文摘Seed maturation is a critical development transition and it largely affects the final yield and quality of crops.Abscisic acid(ABA)-activated sucrose-non-fermentation kinase subfamily 2(SnRK2s)constitute a well-known regulatory network that modulate seed maturation in Arabidopsis;however,the underlying genetic and regulatory mechanisms in cereal crops remain largely unknown.Here,we found that ABA levels exhibited two distinct peaks during kernel development in maize,corresponding to the lag and maturation phase,respectively.Integrated transcriptome and proteome profiling of kernels treated with exogenous ABA at the pre-maturation stage suggested that the second peak of ABA acts as a trigger for kernel maturation program.Knockout of ZmSnRK2s demonstrated that subclassⅢZmSnRK2s are required for kernel maturation in maize,and the loss-of-function of subclassⅢZmSnRK2s showed a disruption in kernel dehydration and dormancy.We identified a conserved ABA–SnRK2–b ZIP signaling pathway mediating this process in maize.Additionally,ZmSnRK2.10 overexpression accelerates kernel dehydration during maturity,achieving reduced kernel moisture content(KMC)at physiological maturity(PM).Overall,our findings establish ABA-activated SnRK2s as central regulators of kernel maturation in maize and provide valuable genetic resources for breeding maize varieties with low moisture content at harvest.
基金funded by National Natural Science Foundation of China(Grants Nos.41825018 and 42141009)the Second Tibetan Plateau Scientific Expedition and Research Program(Grants No.2019QZKK0904)。
文摘As one of the most serious geological disasters in deep underground engineering,rockburst has caused a large number of casualties.However,because of the complex relationship between the inducing factors and rockburst intensity,the problem of rockburst intensity prediction has not been well solved until now.In this study,we collect 292 sets of rockburst data including eight parameters,such as the maximum tangential stress of the surrounding rock σ_(θ),the uniaxial compressive strength of the rockσc,the uniaxial tensile strength of the rock σ_(t),and the strain energy storage index W_(et),etc.from more than 20 underground projects as training sets and establish two new rockburst prediction models based on the kernel extreme learning machine(KELM)combined with the genetic algorithm(KELM-GA)and cross-entropy method(KELM-CEM).To further verify the effect of the two models,ten sets of rockburst data from Shuangjiangkou Hydropower Station are selected for analysis and the results show that new models are more accurate compared with five traditional empirical criteria,especially the model based on KELM-CEM which has the accuracy rate of 90%.Meanwhile,the results of 10 consecutive runs of the model based on KELM-CEM are almost the same,meaning that the model has good stability and reliability for engineering applications.
文摘This paper considers the following Marcinkiewicz type integrals■which can be regarded as an extension of the classical Marcinkiewicz integral po introduced by Stein in[Trans Amer Math Soc,88(1958):159-172],where Ω is a homogeneous function of degree zero on R^(n)with mean value zero in the unit sphere S^(n-1),Under the assumption that Ω∈L^(∞)(S^(n-1)),the authors establish the L^(q)-estimate and weak(1,1)type estimate as well as the corresponding weighted estimates for po.s with 1<q<∞ and 0<β(q-1)n/q.Moreover,the bounds do not depend on β and the strong(q,q)type and weak(1,1)type estimates for the classical Marcinkiewicz integral po can be recovered from the above estimates of μΩ,β whenβ→0.
