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ProNet Adaptive Retinal Vessel Segmentation Algorithm Based on Improved UperNet Network

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Computers, Materials & Continua 2024年第1期78卷 283-302页

作者： Sijia Zhu Pinxiu Wang Ke shen CW Chu College Jiangsu Normal UniversityXuzhou221000China Biomedical Engineering College Southern Medical UniversityGuangzhou510080China

This paper proposes a new network structure,namely the ProNet *** medical image segmentation can help clinical diagnosis of related eye diseases and is essential for subsequent rational *** baseline model of the ProNet network is UperNet(Unified perceptual parsing Network),and the backbone network is ConvNext(Convolutional Network).A network structure based on depth-separable convolution and 1×1 convolution is used,which has good performance and *** further optimise ProNet mainly in two *** is data enhancement using increased noise and slight angle rotation,which can significantly increase the diversity of data and help the model better learn the patterns and features of the data and improve the model’s ***,it can effectively expand the training data set,reduce the influence of noise and abnormal data in the data set on the model,and improve the accuracy and reliability of the *** is the loss function aspect,and we finally use the focal loss *** focal loss function is well suited for complex tasks such as object *** function will penalise the loss carried by samples that the model misclassifies,thus enabling better training of the model to avoid these errors while solving the category imbalance problem as a way to improve image segmentation density and segmentation *** the experimental results,the evaluation metrics mIoU(mean Intersection over Union)enhanced by 4.47%,and mDice enhanced by 2.92% compared to the baseline *** generalization effects and more accurate image segmentation are achieved.

关键词： Retinal segmentation multifaceted optimization cross-fusion data enhancement focal loss

Structure and Representations for Electrical Lie Algebra of Type D_(5)

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Algebra Colloquium 2024年第2期31卷 271-284页

作者： Yulu Chen Ran shen Yucai Su College of Science Donghua UniversityShanghai 201620China 不详

In this paper,we prove that the electrical Lie algebra e D_(5)is isomorphic to the semidirect product of sp_(4)and a 2-step nilpotent Lie ***,we classify the irreducible highest weight modules for e D_(5).

关键词： electrical Lie algebra 2-step nilpotent Lie algebra highest weight module

Highly efficient photocatalytic conversion of CO_(2) into CH_(4) over Cu single atom promoted heterojunction:The effect of uplifted d-band center

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Chinese Chemical Letters 2024年第2期35卷 484-488页

作者： Hao Zhang Qian Liu Zhurui shen School of Materials Science and Engineering Nankai UniversityTianjin 300350China

Photoreduction of CO_(2) to solar fuels has caused great interest,but suffers from low catalytic efficiency and poor ***,we designed a S-scheme heterojunction(Cu-TiO_(2)/WO_(3))with Cu single atom to significantly boost the photoreduction of CO_(2).Notably,the developed Cu-TiO_(2)/WO_(3) achieved the solardriven conversion of CO_(2) to CH_(4) with an evolution rate of 98.69μmol g^(−1) h^(−1),and the electron selectivity of CH_(4) reached 88.5%.The yield was much higher than those of pristine WO_(3),TiO_(2)/WO_(3) and Cu-TiO_(2) *** and theoretical analysis suggested that the S-scheme heterojunction accelerated charge migration and inhibited the recombination of electron-hole ***,the charge separation effect of the heterojunction meliorated the position of the *** uplifted d-band centers of Cu and Ti on Cu-TiO_(2)/WO_(3) not only improved the electron interaction between Cu single atoms and substrate-TiO_(2),accelerated the adsorption and activation of CO_(2) on the active sites of Cu single atom,but also optimized the Gibbs free energies of CH 4 formation pathway,leading to excellent selectivity toward CH_(4).This work provides new insights into the design of photocatalyst systems with high photocatalytic performance.

关键词： Cu single atom Heterojunction CO_(2)photoreduction d-band center DFT

Recent advances in the culture-independent discovery of natural products using metagenomic approaches

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Chinese Journal of Natural Medicines 2024年第2期22卷 100-111页

作者： shen Yiping LIU Nan WANG Zongqiang Laboratory of Microbial Drug Discovery China Pharmaceutical UniversityNanjing 211198China

Natural products derived from bacterial sources have long been pivotal in the discovery of drug ***,the cultivation of only about 1%of bacteria in laboratory settings has left a significant portion of biosynthetic diversity hidden within the genomes of uncultured *** in sequencing technologies now enable the exploration of genetic material from these metagenomes through culture-independent *** approach involves extracting genetic sequences from environmental DNA and applying a hybrid methodology that combines functional screening,sequence tag-based homology screening,and bioinformatic-assisted chemical *** this process,numerous valuable natural products have been identified and synthesized from previously uncharted metagenomic *** paper provides an overview of the recent advancements in the utilization of culture-independent techniques for the discovery of novel biosynthetic gene clusters and bioactive small molecules within metagenomic libraries.

关键词： Metagenomics Culture-independent approach Natural product Functional screening Sequence tag-based homology screening Syn-BNP

A CELL-CENTERED GODUNOV METHOD BASED ON STAGGERED DATA DISTRIBUTION, PART I: ONE-DIMENSIONAL CASE

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Journal of Computational Mathematics 2024年第4期42卷 1172-1196页

作者： Jiayin Zhai Xiao Li Zhijun shen Institute of Applied Physics and Computational Mathematics LCPP.O.Boc 8009-26Beijing 100088China College of Big Data and Internet Shenzhen Technology UniversityShenzhen 518118China Institute of Applied Physics and Computational Mathematics LCPP.O.Boa 8009-26Beijing 100088China Center for Applied Physics and Technology HEDPSPeking UniversityChina

This paper presents a cell-centered Godunov method based on staggered data distribu-tion in Eulerian *** motivation is to reduce the intrinsic entropy dissipation of classical Godunov methods in the calculation of an isentropic or rarefaction *** the same time,the property of accurate shock capturing is also *** analyzing the factors that cause nonphysical entropy in the conventional Godunov methods,we introduce two velocities rather than a single velocity in a cell to reduce kinetic energy dissipation.A series of redistribution strategies are adopted to update subcell quantities in order to improve *** examples validate that the present method can dramatically reduce nonphysical entropy *** subject classification:35Q35,76N15,76M12.

关键词： Godunov method Riemann solver Rarefaction wave Nonphysical entropy increase.

The CLAVATA signaling:a roadmap to optimize grain shape in rice

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Journal of Genetics and Genomics 2024年第7期51卷 677-679页

作者： Shaoyan shen Bingyang Jiao Yunhai Li Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China College of Advanced Agriculture University of Chinese Academy of SciencesBeijing 100039China

The shoot apical meristem(SAM)is the source of all postembryonic cells in aerial parts of a plant,and large shoot meristems with an increased stem cell population hold promise for enhancing yield(Li et al.,2022).

关键词： grain shape shoot

Second-order error analysis of the averaged L1 scheme L1 for time-fractional initial-value and subdiffusion problems

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Science China Mathematics 2024年第7期67卷 1641-1664页

作者： Jinye shen Fanhai Zeng Martin Stynes School of Mathematics Southwestern University of Finance and EconomicsChengdu611130China School of Mathematics Shandong UniversityJinan250100China Applied and Computational Mathematics Division Beijing Computational Science Research CenterBeijing100193China

Fractional initial-value problems(IVPs) and time-fractional initial-boundary value problems(IBVPs), each with a Caputo temporal derivative of order α ∈(0, 1), are considered. An averaged variant of the well-known L1 scheme is proved to be O(N^(-2)) convergent for IVPs on suitably graded meshes with N points, thereby improving the O(N^(-(2-α))) convergence rate of the standard L1 scheme. The analysis relies on a delicate decomposition of the temporal truncation error that yields a sharp dependence of the order of convergence on the degree of mesh grading used. This averaged L1 scheme can be combined with a finite difference or piecewise linear finite element discretization in space for IBVPs, and under a restriction on the temporal mesh width, one gets again O(N^(-2)) convergence in time, together with O(h^(2)) convergence in space,where h is the spatial mesh width. Numerical experiments support our results.

关键词： time-fractional subdiffusion averaged L1 scheme

Polymer Mechanochemistry on Reactive Species Generated from Mechanochemical Reactions

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Chinese Journal of Chemistry 2024年第12期42卷 1418-1432页

作者： Xiaolong Chen Hang shen Zhengbiao Zhang State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Suzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China

Comprehensive Summary Polymer mechanochemistry on reactive species has attracted more and more attentions over the past 20 years,as the mechanochemical generation of reactive species has a great potential in developing different polymeric materials for various purposes,such as stress detection,self-healing,self-strengthening,controllable degradation and release of small *** this review,we first discuss the recent progress on polymer mechanochemistry of the reactive species that are generated from the mechanochemical reactions of *** types of reactive species,including radical,zwitterion,ionic,carbene and neutral intermediates,and their applications were reviewed in *** mechanochemical reactions are sensitive to the mechanophore structure and polymer framework,we then discuss how mechanophore isomerism,polymer structure,polymer attachment point,and polymer architecture influence the mechanophore *** last,we provide our perspectives on the polymer mechanochemistry of reactivespecies.

关键词： Stimuli-responsive polymers Polymer mechanochemistry Mechanophore Mechanochemical reaction Reactive species

A scoping review of methodologies for applying artificial intelligence to physical activity interventions

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Journal of Sport and Health Science 2024年第3期13卷 428-441页

作者： Ruopeng An Jing shen Junjie Wang Yuyi Yang Brown School Washington UniversitySt.LouisMO 63130USA Department of Physical Education China University of Geosciences BeijingBeijing 100083China School of Kinesiology and Health Promotion Dalian University of TechnologyDalian 116024China Division of Computational and Data Sciences Washington UniversitySt.LouisMO 63130USA

Purpose This scoping review aimed to offer researchers and practitioners an understanding of artificial intelligence(AI)applications in physical activity(PA)interventions;introduce them to prevalent machine learning(ML),deep learning(DL),and reinforcement learning(RL)algorithms;and encourage the adoption of AI *** A scoping review was performed in PubMed,Web of Science,Cochrane Library,and EBSCO focusing on AI applications for promoting PA or predicting related behavioral or health *** methodologies were summarized and categorized to identify synergies,patterns,and trends informing future ***,a concise primer on predominant AI methodologies within the realm of PA was provided to bolster understanding and broader *** The review included 24 studies that met the predetermined eligibility *** models were found effective in detecting significant patterns of PA behavior and associations between specific factors and intervention *** studies comparing AI models to traditional statistical approaches reported higher prediction accuracy for AI models on test *** of different AI models yielded mixed results,likely due to model performance being highly dependent on the dataset and *** increasing trend of adopting state-of-the-art DL and RL models over standard ML was observed,addressing complex human–machine communication,behavior modification,and decision-making *** key areas for future AI adoption in PA interventions emerged:personalized PA interventions,real-time monitoring and adaptation,integration of multimodal data sources,evaluation of intervention effectiveness,expanding access to PA interventions,and predicting and preventing *** The scoping review highlights the potential of AI methodologies for advancing PA *** the field progresses,staying informed and exploring emerging AI-driven strategies is essential for achieving significant improveme

关键词： Artificial intelligence Intervention Machine learning Neural network Physical activity