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Monte Carlo method for evaluation of surface emission rate measurement uncertainty

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Nuclear Science and Techniques 2024年第7期35卷 126-136页

作者： Yuan-qiao Li min Lin Li-Jun Xu Rui Luo Yu-He Zhang Qian-Xi Ni yun-Tao Liu China Institute of Atomic Energy Beijing102413China National Key Laboratory for Metrology and Calibration Techniques Beijing102413China Department of Radiation Oncology Hunan Cancer HospitalChangsha410031China The Affiliated Cancer Hospital of Xiangya School of Medicine Central South UniversityChangsha410031China

The aim of this study is to evaluate the uncertainty of 2πcx and 2πβsurface emission rates using the windowless multiwire proportional counter *** study used the Monte Carlo method(MCM)to validate the conventional Guide to the Expression of Uncertainty in Measurement(GUM)method.A dead time mea surement model for the two-source method was established based on the cha racteristics of a single--channel measurement systemn,and the voltage threshold correction factor measurement function was indi rectly obtained by fitting the threshold correction *** uncertainty in the surface emission rate was calculated using the GUM method and the law of propagation of *** MCM provided clear definitions for each input quantity and its uncertainty distribution,and the simulation training was realized witha complete and complex mathematical *** results of the surface emission rate uncertainty evaluation for four radioactive plane sources using both methods showed the uncertainty's consistency E_(n)<0.070 for the comparison of each source,and the uncertainty results ofthe GUM were all lower than those of the ***,the MCM has a more objective evaluation process and can serve as a validation tool for GUM results.

关键词： Surface emission rate Monte Carlo method Metrology Probability distribution function Dead time Low-energy loss correction Least-squares method

Long-term ocean temperature trend and marine heatwaves

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Journal of Oceanology and Limnology 2024年第4期42卷 1037-1047页

作者： min ZHANG Yangyan CHENG Gang WANG Qi SHU Chang ZHAO Yuanling ZHANG Fangli qiao First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Key Laboratory of Marine Sciences and Numerical Modelling Ministry of Natural ResourcesQingdao 266061China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Marine heatwaves(MHWs)can cause irreversible damage to marine ecosystems and *** MHW characterization remains difficult,because the choice of a sea surface temperature(SST)temporal baseline strongly influences MHW *** a recent work suggesting that there should be a communicating baseline for long-term ocean temperature trends(LTT)and MHWs,we provided an effective and quantitative solution to calculate LTT and MHWs simultaneously by using the ensemble empirical mode decomposition(EEMD)*** long-term nonlinear trend of SST obtained by EEMD shows superiority over the traditional linear trend in that the data extension does not alter prior *** MHWs identified from the detrended SST data exhibited low sensitivity to the baseline choice,demonstrating the robustness of our *** also derived the total heat exposure(THE)by combining LTT and *** THE was sensitive to the fixed-period baseline choice,with a response to increasing SST that depended on the onset time of a perpetual MHW state(identified MHW days equal to the year length).Subtropical areas,the Indian Ocean,and part of the Southern Ocean were most sensitive to the long-term global warming trend.

关键词： marine heatwaves(MHWs) ensemble empirical mode decomposition(EEMD) long-term temperature(LTT)trend total heat exposure(THE)

Disease Burden and Costs Associated with Multiple Sclerosis in China:A Cross-sectional Analysis of Nationwide Survey Data

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Neuroscience Bulletin 2024年第4期40卷 533-538页

作者： Yusheng Jia Xuanqi qiao Jin Zhao Hainan Li Shanlian Hu min Hu Department of Health Economics School of Public HealthFudan UniversityShanghai200032China National Health Commission Key Laboratory of Health Technology Assessment Fudan UniversityShanghai200032China

DearEditors,Multiple sclerosis(MS)is a chronic,autoimmune neurological disorder characterized by inflammatory demyelination of the central nervous system;it is associated with reduced mobility,cognitive impairment,and numerous comorbidities[1].Global MS incidence(2.1 per 100,000 person-years)and prevalence(30.1 per 100,000)have increased in recent years,and its prevalence is notably higher in Western countries,ranging from~30 to 200 cases per 100,000[2].In China,recent epidemiological research has shown that the crude prevalence was 2.44 per 100,000 in 2016[3],and the age-and sex-adjusted incidence was 0.235 per 100,000 person-years[4].Despite the relatively low prevalence compared with the global average,China has extensively addressed the well-being of over 30,000 MS patients,enrolling MS in China's First National List of Rare Diseases in 2018.

关键词： prevalence impairment autoimmune

Synthesis,chemical bonding and reactivity of new medium-sized polyarsenides

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Chinese Chemical Letters 2024年第7期35卷 497-501页

作者： Xu-Hui Yue Xiang-Wen Zhang Hui-min He Lei qiao Zhong-ming Sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Institution Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Physics Institute of Computational and Applied PhysicsTaiyuan Normal UniversityJinzhong 030619China

Gaining an understanding of the growth mechanism from single atoms to clusters and bulk materials continues to present a ***,it is important to explore the evolving trends of clusters in the structure and properties during the size *** this work,we report the synthesis and characterization of two medium-sized chain-like polyarsenic anions.[As_(21)]^(3-)represents a trimeric example of polyarsenic anion assembled through oxidative coupling of As_(7)^(3-)*** anion As_(18)^(4-)included in[As_(18)MO_(2)(CO)_(8)]^(4-)is regarded as formed by two realgar-type As_(8)subunits connected by a dinuclear AsAs *** As_(18)cluster was previously predicted by theory,and this is the first time successfully synthesized using wet chemistry ***,small-sized polyarsenides As_(2)^(2-)and As_(10)^(2-)were found in compound[K(18-crown-6)]_(3)[As_(10)]_(0.5)[As_(4){Mo(CO)_(3)}_(2)]_(0.5)·*** these,the former exhibits coordination with metal ***-crystal X-ray diffraction combined with quantum chemical calculations revealed the formation of double bonded As_(2)^(2-)stabilized by metal carbonyl *** work demonstrates a novel synthetic approach for the preparation of new polyarsenides and highlights their intriguing bonding characteristics,laying the foundation for the synthesis of such compounds and paving the way for their potential applications.

关键词： Polyarsenide Zintl anions Chain-like cluster DFT calculations AdNDP

CTSN: Predicting cloth deformation for skeleton-based characters with a two-stream skinning network

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Computational Visual Media 2024年第3期10卷 471-485页

作者： Yudi Li min Tang yun Yang Ruofeng Tong Shuangcai Yang Yao Li Bailin An Qilong Kou College of Computer Science and Technology Zhejiang UniversityHangzhou 310058China Aurora Studios TencentShenzhen 518057China

We present a novel learning method using a two-stream network to predict cloth deformation for skeleton-based *** characters processed in our approach are not limited to humans,and can be other targets with skeleton-based representations such asﬁsh or *** use a novel network architecture which consists of skeleton-based and mesh-based residual networks to learn the coarse features and wrinkle features forming the overall residual from the template cloth *** network may be used to predict the deformation for loose or tight-fitting *** memory footprint of our network is low,thereby resulting in reduced computational *** practice,a prediction for a single cloth mesh for a skeleton-based character takes about 7 ms on an nVidia GeForce RTX 3090 *** to prior methods,our network can generate finer deformation results with details and wrinkles.

关键词： cloth deformation learning network skinning

A Novel Divide and Conquer Solution for Long-term Video Salient Object Detection

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Machine Intelligence Research 2024年第4期21卷 684-703页

作者： yun-Xiao Li Cheng-Li-Zhao Chen Shuai Li Ai-min Hao Hong Qin State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China Department of Computer Science Stony Brook UniversityNew York 11794USA

Recently,a new research trend in our video salient object detection(VSOD)research community has focused on enhancing the detection results via model self-fine-tuning using sparsely mined high-quality keyframes from the given *** such a learning scheme is generally effective,it has a critical limitation,i.e.,the model learned on sparse frames only possesses weak generalization *** situation could become worse on“long”videos since they tend to have intensive scene ***,in such videos,the keyframe information from a longer time span is less relevant to the previous,which could also cause learning conflict and deteriorate the model ***,the learning scheme is usually incapable of handling complex pattern *** solve this problem,we propose a divide-and-conquer framework,which can convert a complex problem domain into multiple simple ***,we devise a novel background consistency analysis(BCA)which effectively divides the mined frames into disjoint *** for each group,we assign an individual deep model on it to capture its key attribute during the fine-tuning *** the testing phase,we design a model-matching strategy,which could dynamically select the best-matched model from those fine-tuned ones to handle the given testing *** experiments show that our method can adapt severe background appearance variation coupling with object movement and obtain robust saliency detection compared with the previous scheme and the state-of-the-art methods.

关键词： Video salient object detection background consistency analysis weakly supervised learning long-term information background shift.

Collembolans maintain a core microbiome responding to diverse soil ecosystems

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Soil Ecology Letters 2024年第1期6卷 33-46页

作者： Zhe-Lun Liu Dong Zhu Yi-Fei Wang Yong-Guan Zhu min qiao State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

The unique gut habitat led to a core intestinal micro-biome in diverse soil *** collembolan guts may help eliminate soil ***-selection carried more weight on community assembly of gut *** invertebrates are widely distributed in the ecosystem and are essential for soil ecological ***-brate gut microbiome plays an important role in host health and has been considered as a hidden microbial ***,little is known about how gut microbiome in soil invertebrates respond to diverse soil *** on a laboratory microcosm experiment,we characterized the assembling of microbiome of soil collembolans(Folsomia candida)from six representative regions of the soil ecosystem which they *** showed that collembolan gut microbial communities differed significantly from their surrounding soil microbial communities.A dominant core gut microbiome was identified in gut *** analyses indicated that deterministic process dominated in the community assembly of collembolan gut *** results further demonstrate a dominant contribution of host selection in shaping gut *** is also worthy to mention that pathogens,such as common agricultural phytopathogenic fungi Fusarium,were involved in core microbiome,indicating that collembolans could act as vectors of *** results unravelled the existence of gut core microbiome of collembolans in soil ecosystems and provided new insights for under-standing the crucial role of gut microbiome of soil fauna in maintaining microbial biodiversity and stability of soil ecosystems.

关键词： gut microbiome collembolan core microbiome community assembly

Spatial construction of ultrasmall Pt-decorated 3D spinel oxidemodified N-doped graphene nanoarchitectures as high-efficiency methanol oxidation electrocatalysts

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Rare Metals 2024年第1期43卷 186-197页

作者： Qi Zhang min-min Yan Wen-Fa Du Chen-Yu Yin Jian Zhang Lu Yang yun-Qing Kang Hai-Yan He Hua-Jie Huang College of Mechanics and Materials Hohai UniversityNanjing 210098China New Energy Technology Engineering Lab of Jiangsu Province College of ScienceNanjing University of Posts&Telecommunications(NUPT)Nanjing 210023China International Center for Materials Nanoarchitectonics(WPIMANA) National Institute for Materials ScienceTsukuba 305-0044IbarakiJapan

Direct methanol fuel cell technology recently becomes the focus of both academic and engineering circles,which stimulates the exploitation and utilization of advanced electrode catalysts with high activity and long ***,we demonstrate a robust bottom-up approach to the spatial construction of three-dimensional(3D) spinel manganese-cobalt oxide-modified N-doped graphene nanoarchitectures decorated with ultrasmall Pt nanoparticles(Pt/MnCo_(2)O_(4)-NG) via a controllable selfassembly *** incorporation of MnCo_(2)O_(4)nanocrystals provides abundant hydroxyl sources to promote the oxidative removal of CO-like byproducts on Pt sites,while the existence of 3D porous N-doped graphene networks facilitates the transportation of both ions and electrons in the hybrid system,thus giving rise to remarkable synergetic coupling effects during the methanol oxidation ***,the optimized Pt/MnCo_(2)O_(4)-NG nano architecture expres ses exceptional electrocatalytic properties with a large electrochemically active surface area of 99.5 m^(2)·g^(-1),a high mass activity of1508.3 mA·mg^(-1),strong toxicity resistance and reliable long-term durability,which have obvious competitive advantages over those of conventional Pt/carbon black,Pt/carbon nano tube,Pt/graphene,and Pt/N-doped graphene catalysts with the same Pt usage.

关键词： Platinum MnCo_(2)O_(4) 3D graphene Electrocatalysts Methanol oxidation

Further study on the genesis of lamellar calcite veins in lacustrine black shale--A case study of Paleogene in Dongying Depression, China

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Petroleum Science 2024年第3期21卷 1508-1523页

作者： Guan-min Wang yun-Jiao Zhang Zi-Yuan Yin Rui Zhu Zhi-Yao Hou Yu Bai School of Geosciences China University of Petroleum(East China)Qingdao266580ShandongChina

Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark *** formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving *** paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe *** distinct types of calcite veins have been identified:granular calcite veins and sparry calcite *** two types differ significantly in color,grain structure,morphology,and *** further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite *** granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite *** granular calcite veins were likely influenced by the reduction of sulfate *** the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic *** contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion *** carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of *** opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarb

关键词： Calcite veins Shale diagenesis Material source Formation period Formation mechanism