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Science China Mathematics 2024年第2期67卷 405-430页

作者： Junzhuo Gao Lei wang Heng lian School of Statistics and Data Science&LPMC Nankai UniversityTianjin 300071China Department of Mathematics City University of Hong KongHong KongChina

In this paper, we consider the unified optimal subsampling estimation and inference on the lowdimensional parameter of main interest in the presence of the nuisance parameter for low/high-dimensionalgeneralized linear models (GLMs) with massive data. We first present a general subsampling decorrelated scorefunction to reduce the influence of the less accurate nuisance parameter estimation with the slow convergencerate. The consistency and asymptotic normality of the resultant subsample estimator from a general decorrelatedscore subsampling algorithm are established, and two optimal subsampling probabilities are derived under theA- and L-optimality criteria to downsize the data volume and reduce the computational burden. The proposedoptimal subsampling probabilities provably improve the asymptotic efficiency of the subsampling schemes in thelow-dimensional GLMs and perform better than the uniform subsampling scheme in the high-dimensional GLMs.A two-step algorithm is further proposed to implement, and the asymptotic properties of the correspondingestimators are also given. Simulations show satisfactory performance of the proposed estimators, and twoapplications to census income and Fashion-MNIST datasets also demonstrate its practical applicability.

关键词： A-optimality decorrelated score subsampling high-dimensional inference L-optimality massive data

Morphogenesis and Molecular Phylogeny of a Marine Urostylid Ciliate Apokeronopsis wrighti(Protista, Ciliophora, Hypotrichia)

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Journal of Ocean University of China 2024年第4期23卷 1067-1075页

作者： lian Chunyu LI Ping ZHANG Tengteng SHAO chen Department of Zoology College of Life SciencesShaanxi Normal UniversityXi’an 710119China Powerchina Northwest Engineering Corporation Limited Xi’an 710065China

Hypotrichs are one of the highly differentiated ciliated lineages which play important roles in ecological, environmental,evolutionary and basic biological studies. In the present study, we investigated the living characteristics, infraciliature, nuclear apparatus, ontogenesis and phylogenetic position of a marine hypotrichous ciliate, Apokeronopsis wrighti Long et al., 2008, which was isolated from coastal waters in Shenzhen, China. The new isolate resembles the type population in terms of morphological characteristics, morphometrics, and SSU rRNA gene sequence that is with a 99.7% similarity. Ontogenesis of A. wrighti is characterized by oral primordium for the proter as well as marginal and dorsal kineties anlagen in both filial products formed de novo, and the cirral row arranged along the paroral and endoral arises from several anterior frontoventral-transverse cirral streaks. Phylogenetic analyses based on SSU and concatenated gene data suggest that five species of Apokeronopsis form a monophyletic clade, and the genus Apokeronopsis is closely related to Thigmokeronopsis and Metaurostylopsis.

关键词： 18S rRNA gene Apokeronopsis ciliated protists multi-gene ontogenesis systematics Urostylida

Integrated biomarker response to assess toxic impacts of iron and manganese on deep-sea mussel Gigantidas platifrons under a deep-sea mining activity scenario

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Journal of Oceanology and Limnology 2024年第2期42卷 522-532页

作者： Li ZHOU Mengna LI Zhaoshan ZHONG Minxiao wang Hao chen Chao lian Hao wang Huan ZHANG Lei CAO Chaolun LI Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan Laboratory Qingdao 266237China South China Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Deep-sea mining activities can potentially release metals,which pose a toxicological threat to deep-sea ***,due to the remoteness and inaccessibility of the deep-sea biosphere,there is insufficient knowledge about the impact of metal exposure on its *** this study,deep-sea mussel Gigantidas platifrons,a commonly used deep-sea toxicology model organism,was exposed to manganese(100,1000μg/L)or iron(500,5000μg/L)for 7 d,*** and iron were chosen for their high levels of occurrence within deep-sea *** accumulation and a battery of biochemical biomarkers related to antioxidative stress in superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA);immune function in alkaline phosphatase(AKP),acid phosphatase(ACP);and energy metabolism in pyruvate kinase(PK)and hexokinase(HK)were assessed in mussel *** showed that deep-sea mussel *** exhibited a high capacity to accumulate Mn/*** addition,most tested biochemical parameters were altered by metal exposure,demonstrating that metals could induce oxidative stress,suppress the immune system,and affect energy metabolism of deep-sea *** integrated biomarker response(IBR)approach indicated that the exposure to Mn/Fe had a negative impact on deep-sea mussels,and Mn demonstrated a more harmful impact on deep-sea mussels than ***,SOD and CAT biomarkers had the greatest impact on IBR values in Mn treatments,while ACP and HK were most influential for the low-and high-dose Fe groups,*** study represents the first application of the IBR approach to evaluate the toxicity of metals on deep-sea fauna and serves as a crucial framework for risk assessment of deep-sea mining-associated metal exposure.

关键词： mussel metal deep-sea mining biomarker environmental monitoring

Chemodivergent Synthesis of Benzofurans and 2,3-Dihydrobenzofurans via Tandem Oxidative Annulation of Enaminones and Salicylaldehydes

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Chinese Journal of Chemistry 2024年第15期42卷 1727-1733页

作者： Xiyan Duan Hui Li Junqi wang Kun Liu Meixin Shi Weidong lian Ran chen Pu Liu School of Chemistry&Chemical Engineering Henan University of Science and TechnologyLuoyangHenan 471003China

Chemodivergent synthesis of benzofurans and 2,3-dihydrobenzofurans has been *** a reaction system consisting of DBDMH and K_(2)CO_(3) as promotors,controlled conditions enabled the formation of two sets of valuable heterocycles from the tandem transformation of enaminones and *** key to success was the identification of the reaction parameters,in which the imine intermediate which was formed by transient halogenation coupling and substitution processes underwent either aldol condensation/annulation or imine hydrolysis/aldol *** additives NH_(4)Cl or Fe_(2)(SO_(4))_(3) controlled the unique selectivity of this reaction.A broad substrate scope of enaminones and salicylaldehydes has been employed in this reaction,demonstrating excellent functional group tolerance and versatility.

关键词： Cross-coupling Umpolung Domino reactions Enaminone Benzofurans 2,3-Dihydrobenzofurans

A new 4-Ti-added polyoxometalate

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Tungsten 2024年第2期6卷 465-471页

作者： Hai-Lou Li chen lian Guo-Yu Yang MOE Key Laboratory of Cluster Science School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 102488China

A new inorganic–organic hybrid 4-Ti-added polyoxometalate:[H_(2)N(CH_(3))_(2)]_(2)Na_(3)H_(5)[{Ti(C_(2)O_(4))(H_(2)O)}_(2){Ti(C_(2)O_(4))}_(2)(B-β-SbW_(9)O_(33))_(2)]·22H_(2)O(1)has been successfully made and further characterized by infrared spectroscopy,thermogravimetric analysis,powder X-ray diff raction and single-crystal X-ray diff *** polyoxoanion of 1 exhibits a Krebs-type structure that is constructed from two[B-β-SbW_(9)O_(33)]^(9)−fragments fused together by a belt of four additional Ti atoms decorated by oxalate ***,1 as a heterogeneous catalyst exhibits high activity for Knoevenagel condensation under mild reaction conditions.

关键词： Polyoxometalate Ti-added POM Krebs-type structure Knoevenagel condensation

Impact of short-term ambient air pollution exposure on the risk of severe COVID-19

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Journal of Environmental Sciences 2024年第1期135卷 610-618页

作者： Baihuan Feng Jiangshan lian Fei Yu Dan Zhang Weizhen chen Qiwang Yifei Shen Guoliang Xie Ruonan wang Yun Teng Bin Lou Shufa Zheng Yida Yang Yu chen Department of Laboratory Medicine The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China Key Laboratory of Clinical In Vitro Diagnostic Techniques of Zhejiang Province Hangzhou 310000China Institute of Laboratory Medicine Zhejiang UniversityHangzhou 310000China Department of Infectious Diseases The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious Diseasesthe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310000China

Ecological studies suggested a link between air pollution and severe COVID-19 outcomes,while studies accounting for individual-level characteristics are *** the present study,we aimed to investigate the impact of short-term ambient air pollution exposure on disease severity among a cohort of 569 laboratory confirmed COVID-19 patients admitted to designated hospitals in Zhejiang province,China,from January 17 to March 3,2020,and elucidate the possible biological processes involved using *** with mild cases,severe cases had higher proportion of medical conditions as well as unfavorable results in most of the laboratory tests,and manifested higher air pollution exposure *** exposure to air pollutants was associated with increased risk of severe COVID-19 with odds ratio(OR)of 1.89(95%confidence interval(CI):1.01,3.53),2.35(95%CI:1.20,4.61),2.87(95%CI:1.68,4.91),and 2.01(95%CI:1.10,3.69)for PM_(2.5),PM_(10),NO_(2)and CO,*** for NO_(2)remained significant in two-pollutant models after adjusting for other *** analysis showed 884 differentially expressed genes which mainly were enriched in virus clearance related biological processes between patients with high and low NO_(2)exposure levels,indicating that compromised immune response might be a potential underlying mechanistic *** findings highlight the impact of shortterm air pollution exposure,particularly for NO_(2),on COVID-19 severity,and emphasize the significance in mitigating the COVID-19 burden of commitments to improve air quality.

关键词： Air pollution COVID-19 Severity Transcriptomics Immune response

Parameter calibration of discrete element model for alfalfa seeds based on EDEM simulation experiments

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 33-38页

作者： Xinjiu Zhang Hongti wang Fangyan wang Zhengguo lian College of Mechanical and Electrical Engineering Qingdao Agricultural UniversityQingdao 266109ShandongChina

In order to establish an accurate discrete element model of alfalfa seeds,real physical experiments were combined with simulation experiments,and the contact parameters of alfalfa seeds were calibrated using the repose angle of alfalfa seeds as the response *** intrinsic parameters(thousand grain weight,triaxial size,density)and contact parameters(static friction coefficient,rolling friction coefficient)of alfalfa seeds were obtained through physical experiments,and a spherical particle model was *** the Plackett Burman experiment,the static friction coefficient between alfalfa seeds,the rolling friction coefficient between alfalfa seeds,and the static friction coefficient between alfalfa seeds and ABS plastic were determined to have a significant impact on the *** steepest climb test is used to narrow down the selection range of the optimal parameters,and the box Behnken test is used to obtain the quadratic regression equation of the repose *** optimal parameter combination was obtained with the objective of minimizing the repose angle error:the static friction coefficient between alfalfa seeds and alfalfa seeds was 0.418,the rolling friction coefficient between alfalfa seeds and alfalfa seeds was 0.086,and the static friction coefficient between alfalfa seeds and ABS plastic was *** repose angle and mass flow rate experiments show that the model is effective and reliable.

关键词： alfalfa seeds discrete element parameter calibration EDEM

Recommendation System Based on Perceptron and Graph Convolution Network

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Computers, Materials & Continua 2024年第6期79卷 3939-3954页

作者： Zuozheng lian Yongchao Yin Haizhen wang College of Computer and Control Engineering Qiqihar UniversityQiqihar161006China Heilongjiang Key Laboratory of Big Data Network Security Detection and Analysis Qiqihar UniversityQiqihar161006China

The relationship between users and items,which cannot be recovered by traditional techniques,can be extracted by the recommendation algorithm based on the graph convolution *** current simple linear combination of these algorithms may not be sufficient to extract the complex structure of user interaction *** paper presents a new approach to address such issues,utilizing the graph convolution network to extract association *** proposed approach mainly includes three modules:Embedding layer,forward propagation layer,and score prediction *** embedding layer models users and items according to their interaction information and generates initial feature vectors as input for the forward propagation *** forward propagation layer designs two parallel graph convolution networks with self-connections,which extract higher-order association relevance from users and items separately by multi-layer graph ***,the forward propagation layer integrates the attention factor to assign different weights among the hop neighbors of the graph convolution network fusion,capturing more comprehensive association relevance between users and items as input for the score prediction *** score prediction layer introduces MLP(multi-layer perceptron)to conduct non-linear feature interaction between users and items,***,the prediction score of users to items is *** recall rate and normalized discounted cumulative gain were used as evaluation *** proposed approach effectively integrates higher-order information in user entries,and experimental analysis demonstrates its superiority over the existing algorithms.

关键词： Recommendation system graph convolution network attention mechanism multi-layer perceptron

Inhibiting the phase transition of WO_(3)for highly stable aqueous electrochromic battery

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Journal of Energy Chemistry 2024年第8期95卷 86-95,I0003页

作者： Zhisheng Wu Zhendong lian Ting Ding Jielei Li Jincheng Xu Jinxiao wang liangxing Zhang Bo wang Shi chen Peng Xiao Hua Xu Shuang-Peng wang Kar Wei Ng Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeMacao 999078China School of Applied Physics and Materials Wuyi UniversityJiangmen 529020GuangdongChina Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology School of Physics and Optoelectronic EngineeringFoshan UniversityFoshan 528225GuangdongChina Guangzhou New Vision Optoelectronic Technology Co. Ltd.Guangzhou 510530GuangdongChina

Aqueous electrochromic battery(ECB)has shown intense potential for achieving energy storage and saving *** tungsten oxide(WO_(3))is the most promising EC material for commercialization,the cycling stability of WO_(3)-based aqueous ECBs is currently unsatisfactory due to the repeated phase transition during the redox process and the corrosion by acidic ***,we present a titanium-tungsten oxide alloy(Ti-WO_(3))with controllable morphology and crystal phase synthesized by a facile hot injection method to overcome the *** contrast to conventional monoclinic WO_(3),the Ti-WO_(3)nanorods can stably maintain their cubic crystal phase during the redox reaction in an acidic electrolyte,thus leading to dramatically enhanced response speed and cycling stability,Specifically,when working in a well-matched hybrid Al^(3+)/Zn^(2+)aqueous electrolyte,our phasetransition-free cubic Ti-WO_(3)exhibits an ultra-high cycling stability(>20000 cycles),fast response speed(3,95 s/4,65 s for bleaching/coloring),as well as excellent discharge areal capacity of 214.5 mA h m^(-2),We further fabricate a fully complementa ry aqueous electrochromic device,for the first time,using a Ti-WO_(3)/Prussian blue device ***,the complementary ECB shows>10000 stable operation cycles,attesting to the feasibility of our Ti-WO_(3)for practical *** work validates the significance of inhibiting the phase transitions of WO_(3)during the electrochromic process for realizing highly cyclable aqueous ECB,which can possibly provide a generalized design guidance for other high-quality metallic oxides for electrochemical applications.

关键词： Aqueous electrochromic battery Ti-WO_(3) Phase transition Long-term stability