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The Bright Single Pulse Emission from PSR B1133+16

Research in Astronomy and Astrophysics 2024年第4期24卷 253-261页

作者： jun Tan Zhi-Gang Wen Zhen wang Xue-Feng Duan Hong-Guang wang Na wang Vishal Gajjar Jian-Ping Yuan Rai Yuen Wen-Ming Yan Jian-Ling Chen Wei Han hui wang Cheng-Bing Lyu Ai-jun Dong Maths and Information Technology School Yuncheng UniversityYuncheng 044000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Space Science Laboratory University of CaliforniaBerkeley 94710USA Department of Physics and Electronic Engineering Yuncheng UniversityYuncheng 044000China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China

We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio *** time resolution data(61μs)were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr.A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse ***,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse *** majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately *** pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-*** updated nulling fraction of 15.35%±0.45% was determined from the energy *** emission of individual pulses follows a log-normal distribution in peak flux density *** is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first *** physical mechanisms are discussed in detail to provide insights into these observations.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR B1133+16) methods:observational methods:data analysis

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中国成年居民膳食嘌呤摄入状况分析

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中国食物与营养 2024年第10期30卷 73-77页

作者：董孟茹魏艳丽欧阳一非陈慕磊王惠君刘爱东王志宏董小辉张继国中国疾病预防控制中心营养与健康所北京100050 中国疾病预防控制中心北京102206 国家卫生健康委公共营养与健康重点实验室北京100050

目的:描述中国15省(自治区、直辖市)成年居民每日膳食嘌呤摄入状况、食物来源及变化趋势。方法:利用“中国健康与营养调查”1991—2018年间10轮随访数据,选择18岁及以上成年居民作为研究对象。采用“连续3天24小时”膳食回顾法调查居民... 详细信息

目的:描述中国15省(自治区、直辖市)成年居民每日膳食嘌呤摄入状况、食物来源及变化趋势。方法:利用“中国健康与营养调查”1991—2018年间10轮随访数据,选择18岁及以上成年居民作为研究对象。采用“连续3天24小时”膳食回顾法调查居民食物摄入量和称重法调查调味品消费量。根据各类食物的消费数据和食物中嘌呤含量资料计算中国居民膳食嘌呤摄入量,并分析其食物来源。结果:与1991年相比,2018年中国成年居民总嘌呤、鸟嘌呤、腺嘌呤、次黄嘌呤、黄嘌呤中位数摄入量分别增加了75.9、21.0、12.9、36.5、2.0mg/d。来源于畜禽肉类的嘌呤比例从1991年的28.0%增加至2018年的30.4%,来源于水产品类的嘌呤比例从1991年8.2%增加至2018年的11.7%,来源于蔬菜类的嘌呤比例从1991年的21.5%下降至2018年的11.4%。结论:中国成年居民的膳食嘌呤摄入量呈上升趋势,食物来源主要是动物性食物和谷薯类,应引导居民合理膳食,减少高嘌呤食物的摄入。

关键词：嘌呤摄入量成年居民

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Galerkin-based quasi-smooth manifold element(QSME)method for anisotropic heat conduction problems in composites with complex geometry

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 137-154页

作者： Pan wang Xiangcheng HAN Weibin WEN Baolin wang jun LIANG School of Civil Engineering Central South UniversityChangsha 410083China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China School of Science Harbin Institute of TechnologyShenzhen 518055Guangdong ProvinceChina

The accurate and efficient analysis of anisotropic heat conduction problems in complex composites is crucial for structural design and performance evaluation. Traditional numerical methods, such as the finite element method(FEM), often face a trade-off between calculation accuracy and efficiency. In this paper, we propose a quasi-smooth manifold element(QSME) method to address this challenge, and provide the accurate and efficient analysis of two-dimensional(2D) anisotropic heat conduction problems in composites with complex geometry. The QSME approach achieves high calculation precision by a high-order local approximation that ensures the first-order derivative *** results demonstrate that the QSME method is robust and stable, offering both high accuracy and efficiency in the heat conduction analysis. With the same degrees of freedom(DOFs), the QSME method can achieve at least an order of magnitude higher calculation accuracy than the traditional FEM. Additionally, under the same level of calculation error, the QSME method requires 10 times fewer DOFs than the traditional FEM. The versatility of the proposed QSME method extends beyond anisotropic heat conduction problems in complex composites. The proposed QSME method can also be applied to other problems, including fluid flows, mechanical analyses, and other multi-field coupled problems, providing accurate and efficient numerical simulations.

关键词： anisotropic heat conduction quasi-smooth manifold element(QSME) composite with complex geometry numerical simulation finite element method(FEM)

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Complex interactions among insect viruses-insect vector-arboviruses

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Insect Science 2024年第3期31卷 683-693页

作者： hui wang Qian Chen Taiyun Wei State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops Vector-borne Virus Research CenterFujian Agriculture and ForestryUniversityFuzhouChina

Insects are the host or vector of diverse viruses including those that infect vertebrates,plants,and *** viruses reside inside their insect hosts and are vertically transmitted from parent to *** insect virus-host relationship is intricate,as these viruses can impact various aspects of insect biology,such as development,reproduction,sex ratios,and ***-borne viruses(arboviruses)that cause substantial global health or agricultural problems can also be vertically transmitted to insect vector *** infections with insect viruses and arboviruses are common in *** coinfections involve complex interactions,including synergism,dependence,and *** studies have shed light on the influence of insect viruses on the competence of insect vectors for *** this review,we focus on the biological effects of insect viruses on the transmission of arboviruses by *** also discuss the potential mechanisms by which insect viruses affect the ability of hosts to transmit arboviruses,as well as potential strategies for disease control through manipulation of insect *** of the interactions among insect vectors,insect viruses and arboviruses will provide new opportunities for development of innovative strategies to control arbovirus transmission.

关键词： arbovirus insect biology insect vectors insect virus interaction transmission

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A Task Scheduling Algorithm Based on Clustering Pre-processing in Space-Based Information Network

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Chinese Journal of Electronics 2024年第1期33卷 217-230页

作者： Yufei wang jun LIU Shengnan ZHANG Sai XU Jingyi wang School of Computer Science and Engineering Northeastern University

With the diversification of space-based information network task requirements and the dramatic increase in demand, the efficient scheduling of various tasks in space-based information network becomes a new challenge. To address the problems of a limited number of resources and resource heterogeneity in the space-based information network, we propose a bilateral pre-processing model for tasks and resources in the scheduling pre-processing stage. We use an improved fuzzy clustering method to cluster tasks and resources and design coding rules and matching methods to match similar categories to improve the clustering effect. We propose a space-based information network task scheduling strategy based on an ant colony simulated annealing algorithm for the problems of high latency of space-based information network communication and high resource dynamics. The strategy can efficiently complete the task and resource matching and improve the task scheduling performance. The experimental results show that our proposed task scheduling strategy has less task execution time and higher resource utilization than other algorithms under the same experimental conditions. It has significantly improved scheduling performance.

关键词： Scheduling algorithms Heuristic algorithms Clustering methods Clustering algorithms Simulated annealing Dynamic scheduling Search problems

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Preparation of three-dimensional nanoporous copper foil with high specific surface area

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Rare Metals 2024年第7期43卷 3430-3437页

作者： Ning Song Li-Juan wang jun-Feng wang Juan Liao Jian Huang Peng-Kang Du Yun-Zhi Tang Yu-hui Tan Xiao-Wei Fan Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry School of Chemistry and Chemical EngineeringJiangxi University of Science and TechnologyGanzhou 341000China

The porous copper foil material has the advantages of ultralight and ultra-thin,and can prevent dangers such as thermal runaway and battery fire,which could be regarded as a prospective material for lithium battery **... 详细信息

关键词： copper porous dimensional

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Local Hamilton type Gradient Estimates and Harnack Inequalities for Nonlinear Parabolic Equations on Riemannian Manifolds

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 539-546页

作者： Wen wang Da-peng XIE hui ZHOU School of Mathematics and Statistics Hefei Normal UniversityHefei 230601China

In this paper,we prove a local Hamilton type gradient estimate for positive solution of the nonlinear parabolic equation ut(x,t)=Δu(x,t)+au(x,t) ln u(x,t)+bu^(α)(x,t),on M×(-∞,∞) with α∈R,where a and b are *** ... 详细信息

关键词： nonlinear parabolic equation gradient estimate Harnack inequality

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Greedy is Good:Constrained Non-submodular Function Maximization via Weak Submodularity

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Journal of the Operations Research Society of China 2024年第3期12卷 627-648页

作者： Ma-jun Shi Wei wang School of Statistics Xi’an University of Finance and EconomicsXi’an710100ShaanxiChina School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

The widely used greedy algorithm has been recently shown to achieve near-optimal theoretical guarantees for the problems of constrained monotone non-submodular function maximization,with competitive performances in *** this paper,we investigate the problems of maximizing monotone non-submodular set functions under three classes of independent system constraints,including p-matroid intersection constraints,p-extendible system constraints and p-system *** prove that the greedy algorithm yields an approximation ratio ofγ/p+γfor the former two problems,andξγ/p+ξγfor the last problem,which further has been improved toγ/p+γ,whereγ,ξdenote the submodularity ratio and the diminishing returns ratio of set function *** addition,we also show that the greedy guarantees have a further refinement of for all the problems mentioned above,whereαis the generalized curvatureξ/p+αγof set ***,we show that our greedy algorithm does yield competitive practical performances using a variety of experiments on synthetic data.

关键词： Non-submodular function p-matroid intersection p-extendible system p-system Greedy algorithm

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Metagenomics reveals the microbial community and functional metabolism variation in the partial nitritation-anammox process:From collapse to recovery

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Journal of Environmental Sciences 2024年第1期135卷 210-221页

作者： Hong wang hui Gong Xiaohu Dai Min Yang State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China BIOMATH Department of Data Analysis and Mathematical ModellingGhent UniversityGhent 9000Belgium

Mainstream partial nitritation-anammox(PNA)process easily suffers from performance instability and even reactor collapse in ***,it is of great significance to unveil the characteristic of performance recovery,understand the intrinsic mechanism and then propose operational *** this study,we combined long-term reactor operation,batch tests,and metagenomics to reveal the succession of microbial community and functional metabolism variation from system collapse to *** aeration control(0.10-0.25mg O_(2)/L)was critical for performance *** was also found that Candidatus Brocadia became the dominant flora and its abundance increased from 3.5%to 11.0%.Significant enhancements in carbon metabolism and phospholipid biosynthesis were observed during system recovery,and the genes abundance related to signal transduction was dramatically *** up-regulation of sdh and suc genes showed the processes of succinate dehydrogenation and succinyl-CoA synthesis might stimulate the production of amino acids and the synthesis of proteins,thereby possibly improving the activity and abundance of AnAOB,which was conducive to the performance ***,the increase in abundance of hzs and hdh genes suggested the enhancement of the anammox *** in the abundance of key genes involved in nitrogen metabolism indicated that nitrogen removal pathway was more diverse after system *** achievement of performance recovery was driven by anammox,nitrification and denitrification coupled with dissimilatory nitrate reduction to *** results provide deeper insights into the recovery mechanism of PNA system and also provide a potential regulation strategy for the stable operation of the mainstream PNA process.

关键词： Partial nitritation-anammox Metagenomics Microbial community Functional metabolism Recovery

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In vivo label-free measurement of blood flow velocity symmetry based on dual line scanning third-harmonic generation microscopy excited at the 1700 nm window

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 61-68页

作者： hui Cheng Jincheng Zhong Ping Qiu Ke wang Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen 518060 P.R.China

Measurement of bloodflow velocity is key to understanding physiology and pathology in *** most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the instantaneous bloodflow velocity *** is mainly due to the lack of measurement technology with high spatial and temporal ***,we tackle this problem with our recently developed dual-wavelength line-scan third-harmonic generation(THG)imaging *** acquisition of dual-wavelength THG line-scanning signals enables measurement of bloodflow velocities at two radially symmetric positions in both venules and arterioles in mouse brain in *** results clearly show that the instantaneous bloodflow velocity is not symmetric under general conditions.

关键词： 1700 nm-Window third-harmonic generation imaging blood flow velocity

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