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Acta Mathematica Sinica,English Series 2024年第4期40卷 985-999页

作者： Yi DENG Qiang XIONG shu wei li School of Economics and Statistics Guangzhou UniversityGuangzhou 510006P.R.China

Recurrent event data are commonly encountered in many scientific fields,including biomedical studies,clinical trials and epidemiological surveys,and many statistical methods have been proposed for their *** this paper,we consider to use a weighted composite endpoint of recurrent and terminal events,which is weighted by the severity of each event,to assess the overall effects of covariates on the two types of events.A flexible additive-multiplicative model incorporating both multiplicative and additive effects on the rate function is proposed to analyze such weighted composite event process,and more importantly,the dependence structure among the recurrent and terminal events is left *** the estimation,we construct the unbiased estimating equations by virtue of the inverse probability weighting technique,and the resulting estimators are shown to be consistent and asymptotically normal under some mild regularity *** evaluate the finite-sample performance of the proposed method via simulation studies and apply the proposed method to a set of real data arising from a bladder cancer study.

关键词： Additive-multiplicative rates model estimating equation recurrent events terminal event weighted composite endpoint

Regression Analysis of Doubly Censored Data with a Cured Subgroup under a Class of Promotion Time Cure Models

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Acta Mathematica Sinica,English Series 2021年第6期37卷 835-853页

作者： Min CAI li Qun XIAO shu wei li School of Economics and Statistics Guangzhou UniversityGuangzhou 510006P.R.China

In some situations,the failure time of interest is defined as the gap time between two related events and the observations on both event times can suffer either right or interval *** data are usually referred to as doubly censored data and frequently encountered in many clinical and observational ***,there may also exist a cured subgroup in the whole population,which means that not every individual under study will experience the failure time of interest *** this paper,we consider regression analysis of doubly censored data with a cured subgroup under a wide class of flexible transformation cure ***,we consider marginal likelihood estimation and develop a two-step approach by combining the multiple imputation and a new expectation-maximization(EM)algorithm for its *** resulting estimators are shown to be consistent and asymptotically *** finite sample performance of the proposed method is investigated through simulation *** proposed method is also applied to a real dataset arising from an AIDS cohort study for illustration.

关键词： Doubly censored data marginal likelihood EM algorithm multiple imputation transformation cure models

Design and implementation of self-protection agent for network-based intrusion detection system

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Journal of Central South University of Technology 2003年第1期10卷 69-73页

作者： ZHU shu-ren(朱树人) li wei-qin(李伟琴) Changsha University of Electric Power Changsha 410077 China Beijing University of Aeronautics and Astronautics Beijing 100083 China Beijing University of Aeronautics and Astronautics Beijing 100083 China

Static secure techniques, such as firewall, hierarchy filtering, distributed disposing,layer management, autonomy agent, secure communication, were introduced in distributed intrusion detection. The self-protection agents were designed, which have the distributed architecture,cooperate with the agents in intrusion detection in a loose-coupled manner, protect the security of intrusion detection system, and respond to the intrusion actively. A prototype self-protection agent was implemented by using the packet filter in operation system kernel. The results show that all the hosts with the part of network-based intrusion detection system and the whole intrusion detection system are invisible from the outside and network scanning, and cannot apperceive the existence of network-based intrusion detection system. The communication between every part is secure. In the low layer, the packet streams are controlled to avoid the buffer leaks exist ing in some system service process and back-door programs, so as to prevent users from misusing and vicious attack like Trojan Horse effectively.

关键词： intrusion detection system (IDS) network-based intrusion detection system(NIDS) self-protection agent IP filter

Progress in preparation of AlN-reinforced magnesium matrix composites:A review

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China Foundry 2024年第1期21卷 1-10页

作者： Lu Chen shu-lin Lü Di-jia Zhao wei Guo Jian-yu li shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

As a ceramic material,AlN has very good thermophysical and mechanical *** addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of ***,AlN is an ideal reinforcement for magnesium matrix composites(MMCs),and is attracting increasing *** review addresses the development of preparation technologies for AlN-reinforced Mg matrix *** mainstream preparation techniques include stir casting,melt infiltration,powder metallurgy,and in-situ *** addition,the advantages and disadvantages of these techniques are analyzed in depth,and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

关键词： AlN MMCs preparation thermophysical property mechanical property

Transverse momentum balance of dijets in Xe+Xe collisions at the LHC

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Nuclear Science and Techniques 2024年第7期35卷 137-146页

作者： Yao li shu-Wan Shen Sa Wang Ben-wei Zhang Key Laboratory of Quark&Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan430079China College of Science China Three Gorges UniversityYichang443002China Center for Astronomy and Space Sciences and Institute of Modern Physics China Three Gorges UniversityYichang443002China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou510006China

We present a theoretical study of the medium modifications of the p_(T)balance (x_(J)) of dijets in Xe+Xe collisions at■.The initial production of dijets was carried out using the POWHEG+PYTHIA8 prescription,which matches the next-toleading-order (NLO) QCD matrix elements with the parton shower (PS) *** SHELL model described the in-medium evolution of nucleus–nucleus collisions using a transport *** theoretical results of the dijet xJin the Xe+Xe collisions exhibit more imbalanced distributions than those in the p+p collisions,consistent with recently reported ATLAS *** utilizing the Interleaved Flavor Neutralisation,an infrared-and-collinear-safe jet flavor algorithm,to identify the flavor of the reconstructed jets,we classify dijets processes into three categories:gluon–gluon (gg),quark–gluon (qg),and quark–quark (qq),and investigated the respective medium modification patterns and fraction changes of the gg,qg,and qq components of the dijet sample in Xe+Xe *** is shown that the increased fraction of qg component at a small x_(J)contributes to the imbalance of the dijet;in particular,the q_(1)g_(2)(quark-jet-leading) dijets experience more significant asymmetric energy loss than the g_(1)q_(2)(gluon-jet-leading) dijets traversing the *** comparing the■of inclusive,■ dijets in Xe+Xe collisions,we observe■.Moreover,ρ_(Xe),P_(b),the ratios of the nuclear modification factors of dijets in Xe+Xe to those in Pb+Pb,were calculated,which indicates that the yield suppression of dijets in Pb+Pb is more pronounced than that in Xe+Xe owing to the larger radius of the lead nucleus.

关键词： Heavy-ion collisions Quark-gluon plasma Jet quenching Transverse momentum balance

An emerging role of vitamin D_(3) in amino acid absorption in different intestinal segments of on-growing grass carp(Ctenopharyngodon idella)

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Animal Nutrition 2022年第3期10卷 305-318页

作者： Yao Zhang Chao-Nan li wei-Dan Jiang Pei Wu Yang liu Sheng-Yao Kuang ling Tang shu-wei li Xiao-Wan Jin Hong-Mei Ren Xiao-Qiu Zhou lin Feng Animal Nutrition Institute Sichuan Agricultural UniversityChengduChina Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengduChina Key Laboratory for Animal Disease-resistant Nutrition of China Ministry of Education Sichuan Agricultural UniversityChengduChina Sichuan Animal Science Academy Sichuan Animtech Feed Co.LtdChengduChina Animal Breeding and Genetics Key Laboratory of Sichuan Province Animal Nutrition InstituteSichuan Academy of Animal ScienceChengduChina

Vitamin D_(3)(VD_(3)),an essential nutrient for animals,has been demonstrated to stimulate the uptake of certain amino ***,the role of VD_(3) in the intestine,the primary site for digestion and absorption of nutrients,remains poorly ***,the grass carp(Ctenopharyngodon idella)was studied to assess the influence of different doses of VD_(3)(15.2,364.3,782.5,1,167.9,1,573.8,and 1,980.1 IU/kg)on growth performance,intestinal morphology,digestive absorption,amino acid transport,and potential signaling molecule levels in a feeding *** a result,dietary VD_(3) improved growth performance,intestinal structure,and digestive and brush border enzyme ***,most intestinal free amino acids and their transporters were upregulated after VD_(3) intake,except for Ala,Lys,Asp,Leu,solute carrier(SLC)7A7,SLC1A5,and SLC1A3 mRNA in different segments,Leu and SLC6A14 mRNA in the proximal intestine,and SLC7A5 mRNA in the mid and distal *** the crucial target of rapamycin(TOR)signal pathway of amino acid transport,the gene and protein expression of TOR,S6 kinase 1,and activating transcription factor 4 were elevated,whereas 4E-binding protein 1 was decreased,further suggesting an advanced amino acid absorption capacity in the fish due to VD_(3) *** on percentage weight gain,feed efficiency,and trypsin activity,the VD_(3) requirements of on-growing grass carp were estimated to be 968.33,1,005.00,and 1,166.67 IU/kg,*** findings provide novel recommendations for VD_(3) supplementation to promote digestion and absorption capacities of fish,contributing to the overall productivity of aquaculture.

关键词： Vitamin D_(3) Intestinal segment Intestinal absorption Amino acid transporter Peptide transporter TOR signaling

Attributes of Specialized Households'Resilience and Its Impact on Rural Industrial Advancement:A Case Study of National Musical Instrument Production Specialized Households in Lankao County,Henan,China

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Chinese Geographical Science 2024年第3期34卷 383-400页

作者： WU Nalin wei Yike FAN Sizhe li li SUN Yufan ZHANG Yan shu Yan Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of Educa-tion/The College of Geography and Environmental ScienceHenan UniversityKaifeng 475001China College of Urban and Envir-onmental Science Central China Normal UniversityWuhan 430079China Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Specialized households serve as the primary units within specialized villages in China,and their capacity to withstand risks and external influences significantly shapes the future trajectory of specialized villages and the overall vitality of the rural *** this study,we established a measurement indicator system based on the definition of specialized households’resilience,elucidating the logical connection between specialized households’resilience and rural industrial development in *** musical instrument industry in Lankao County,Henan Province of China,was employed as a case;survey data,the entropy method,and an obstacle diagnosis model were used to examine how instrument production specialized households responded to the challenges posed by Corona Virus Disease 2019(COVID-19)and the tightening of national environmental protection policies,yielding the following key findings:1)there exists substantial variation in the comprehensive resilience levels among different specialized households;2)the ability to learn and adapt is the most significant contributor to the overall resilience level of specialized households;3)technological proficiency and access to skilled talent emerge as pivotal factors influencing specialized households’resilience;4)the positioning of specialized households within the industrial supply chain and the stability of their income have a direct bearing on their resilience *** influence of specialized households’resilience on industrial development primarily manifests in the following ways:stronger resilience correlates with increased stability in production and sales,fostering a more proactive approach to future ***,heightened exposure to the external macroeconomic environment can lead to a higher rate of export *** enhance the development resilience of entities like specialized households and family farms,and to invigorate rural economic development,escalating investments in rural science and technology

关键词： resilience specialized households rural industry Lankao County,China

The guest CH_(3)CN molecule triggers solid-state photochromism in a Cu_(2)I_(2)-based MOF for advanced time-dependent encryption and inkless erasable printing

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Chinese Chemical Letters 2024年第3期35卷 532-537页

作者： Meng-Juan Wang Bo li Yong-li wei shu-Na Zhao shuang-Quan Zang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China College of Chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang 473061China

It remains a big challenge to develop solid-state stimuli-responsive materials for time-dependent information encryption and inkless erasable printing with long retention ***,a 2D Cu_(2)I_(2)-based MOF with photoresponsive spiropyran(SP)groups orderly installed on its skeleton is *** structural isomerization from SP to colored merocyanine(MC)form can be triggered by removing the CH_(3)CN ***,the degree of structural isomerization and the retention time can be adjusted by controlling the amount of CH_(3)CN guests,exhibiting dynamic photochromic behavior with multicolor states and tunable retention *** on these advantages,time-dependent information encryption is successfully ***,the long retention time(>72 h)of the MC form under daylight conditions in the CH_(3)CN-removed Cu_(2)I_(2)-based MOF and good repeatability make it promising in various applications,such as temporary calendars,price-cards,billboards,and reusable identity *** work provides a novel design strategy to fabricate multi-functional MOF-based smart materials for challenging applications of time-dependent information encryption and inkless erasable printing.

关键词： Stimuli-responsive materials Spiropyran Solid-state photochromism Time-dependent encryption Inkless erasable printing

Evolution of inclusions in vacuum induction melting of superalloys containing 70%return material

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Journal of Iron and Steel Research International 2024年第3期31卷 719-728页

作者： Jin-guo Gao shu-lei Yang shu-feng Yang Jing-she li wei liu Meng-jing Zhao An-ren Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Metallurgical and Building Materials Business Department China International Engineering Consulting CorporationBeijing 100048China

The variation law of inclusions type and size in the vacuum induction melting process and ingot of Ni-based superalloy containing 70%return material was studied by industrial test sampling,and the mechanism of inclusions formation was analyzed with thermodynamic *** results show that there are mainly two types of composite inclusions in the vacuum induction melting of Ni-based superalloys,which are nitride-and oxide-based composite inclusions,like Al_(2)O_(3)-SiO_(2)-Cr_(2)O_(3),TiN-(Mo,Nb)C,*** type and proportion of inclusions from the center to the edge of the vacuum induction ingot did not change *** number density of inclusions from the center to the edge of the ingot varied less,and the size of inclusions became smaller from the center to the *** addition,thermodynamic calculations show that oxides(M_(2)O_(3))are present in the liquid phase and mainly contain Al,Ti,Cr,Fe and O *** nitride consists mainly of Ti and N and contains small amounts of Cr,C,Nb,and Mo *** is consistent with the results of industrial *** the temperature decreases,the precipitation phases such as M_(2)O_(3),MN,γ,MC,δ,γ'andμphases are gradually precipitated,where oxides and nitrides are present in the liquid *** contents of O and N elements are the main influencing factors for the inclusions content and precipitation temperature;when the nitrogen content is reduced to below 0.0015%,it can make MN precipitate below the liquid-phase line.

关键词： Ni-based superalloy Vacuum induction melting Return material Inclusion Thermodynamic

Pathological mechanisms of amyotrophic lateral sclerosis

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Neural Regeneration Research 2024年第5期19卷 1036-1044页

作者： Yushu Hu Wenzhi Chen Caihui wei Shishi Jiang shu li Xinxin Wang Renshi Xu Department of Clinical Medicine Nanchang UniversityNanchangJiangxi ProvinceChina Department of Neurology Jiangxi Provincial People’s HospitalNanchangJiangxi ProvinceChina Department of Neurology The First Affiliated Hospital of Nanchang Medical CollegeThe Clinical College of Nanchang Medical CollegeNanchangJiangxi ProvinceChina

Amyotrophic lateral sclerosis refers to a neurodegenerative disease involving the motor system,the cause of which remains unexplained despite several years of ***,the journey to understanding or treating amyotrophic lateral sclerosis is still a long *** to current research,amyotrophic lateral sclerosis is likely not due to a single factor but rather to a combination of mechanisms mediated by complex interactions between molecular and genetic *** progression of the disease involves multiple cellular processes and the interaction between different complex mechanisms makes it difficult to identify the causative factors of amyotrophic lateral ***,we review the most common amyotrophic lateral sclerosis-associated pathogenic genes and the pathways involved in amyotrophic lateral sclerosis,as well as summarize currently proposed potential mechanisms responsible for amyotrophic lateral sclerosis disease and their evidence for involvement in amyotrophic lateral *** addition,we discuss current emerging strategies for the treatment of amyotrophic lateral *** the emergence of these new therapies may help to further our understanding of the pathogenic mechanisms of the disease.

关键词： amyotrophic lateral sclerosis cellular pathways disease mechanisms motor neuron neurodegenerative disease