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UNIQUENESS PROBLEM FOR MEROMORPHIC MAPPINGS IN SEVERAL COMPLEX VARIABLES INTO P^N(C) WITH TRUNCATED MULTIPLICITIES 被引量:4
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作者 涂振汉 王中华 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期122-130,共9页
This paper proves some uniqueness theorems for meromorphic mappings in several complex variables into the complex projective space p^N(C) with truncated multiplicities, and our results improve some earlier work.
关键词 meromorphic mappings truncated multiplicities uniqueness theorems value distribution theory
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Relationships among Three Multiplicities of a Differential Operator’s Eigenvalue 被引量:1
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作者 Shouzhong Fu Zhong Wang 《Applied Mathematics》 2014年第15期2185-2194,共10页
In this paper, the algebraic, geometric and analytic multiplicities of an eigenvalue for linear differential operators are defined and classified. The relationships among three multiplicities of an eigenvalue of the l... In this paper, the algebraic, geometric and analytic multiplicities of an eigenvalue for linear differential operators are defined and classified. The relationships among three multiplicities of an eigenvalue of the linear differential operator are given, and a fundamental fact that the algebraic, geometric and analytic multiplicities for any eigenvalue of self-adjoint differential operators are equal is proven. 展开更多
关键词 Differential OPERATORS EIGENVALUE ALGEBRAIC multiplicities Geometric multiplicities ANALYTIC multiplicities
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TWO MEROMORPHIC FUNCTIONS SHARE SOME PAIRS OF SMALL FUNCTIONS WITH TRUNCATED MULTIPLICITIES
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作者 曹红哲 曹廷彬 《Acta Mathematica Scientia》 SCIE CSCD 2014年第6期1854-1864,共11页
Using the techniques proposed in [3], we prove that two nonconstant meromorphic functions f and g on C must be linked by a quasi-Mbius transformation if they share some pairs of small functions with more precise trunc... Using the techniques proposed in [3], we prove that two nonconstant meromorphic functions f and g on C must be linked by a quasi-Mbius transformation if they share some pairs of small functions with more precise truncated multiplicities, which improve and extend the results of Duc Quang Si. 展开更多
关键词 meromorphic function small function truncated multiplicities quasi-Mbius transformation
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COMPARISON OF CHARGED PARTICLE MULTIPLICITIES IN THREE-JET AND TWO-JET EVENTS FROM e^(+)e^(-) ANNIHILATION AT HIGH ENERGIES
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作者 LIU Ximing 《Chinese Physics Letters》 SCIE CAS CSCD 1989年第5期193-196,共4页
The charged particle multiplicity(n3j) in the three-jet events in e^(+)e^(-) annihilation is considered.The comparison of(n3j) with (n2j) is presented.The prediction of the multiplicity agrees well with experiments.Mo... The charged particle multiplicity(n3j) in the three-jet events in e^(+)e^(-) annihilation is considered.The comparison of(n3j) with (n2j) is presented.The prediction of the multiplicity agrees well with experiments.Moreover,some predictions for high energy range are made. 展开更多
关键词 MULTIPLICITY ANNIHILATION
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Existence and Multiplicities of Solutions for Asymptotically Linear Ordinary Differential Equations Satisfying Sturm-Liouville BVPs with Resonance
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作者 Keqiang Li Ronghua Tong 《Journal of Applied Mathematics and Physics》 2019年第5期1197-1211,共15页
In this paper, we prove existence and multiplicities of solutions for asymptotically linear ordinary differential equations satisfying Sturm-Liouville boundary value conditions with resonance. Adding assumption H3 tha... In this paper, we prove existence and multiplicities of solutions for asymptotically linear ordinary differential equations satisfying Sturm-Liouville boundary value conditions with resonance. Adding assumption H3 that is similar to (LL) in Theorem 1.1, by index theory and Morse theory, we obtain more nontrivial solutions. 展开更多
关键词 Asymptotically Linear Ordinary Differential Equations with RESONANCE Multiple SOLUTIONS STURM-LIOUVILLE Boundary Value Problem Index THEORY Morse THEORY
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Parametric“non-nested”discriminants for multiplicities of univariate polynomials
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作者 Hoon Hong Jing Yang 《Science China Mathematics》 SCIE CSCD 2024年第8期1911-1932,共22页
We consider the problem of complex root classification,i.e.,finding the conditions on the coefficients of a univariate polynomial for all possible multiplicity structures on its complex roots.It is well known that suc... We consider the problem of complex root classification,i.e.,finding the conditions on the coefficients of a univariate polynomial for all possible multiplicity structures on its complex roots.It is well known that such conditions can be written as conjunctions of several polynomial equalities and one inequality in the coefficients.Those polynomials in the coefficients are called discriminants for multiplicities.It is also known that discriminants can be obtained using repeated parametric greatest common divisors.The resulting discriminants are usually nested determinants,i.e.,determinants of matrices whose entries are determinants,and so on.In this paper,we give a new type of discriminant that is not based on repeated greatest common divisors.The new discriminants are simpler in the sense that they are non-nested determinants and have smaller maximum degrees. 展开更多
关键词 parametric polynomial complex roots DISCRIMINANT MULTIPLICITY RESULTANT
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复发的多囊甲状舌管囊肿1例
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作者 刘秀玲 孙艳艳 《中国耳鼻咽喉头颈外科》 2025年第3期201-202,共2页
1临床资料患者,女,37岁,因“发现颈部肿物3周余”于2020-04-16就诊于我院。患者无意中发现颈部肿物,无疼痛,无声音嘶哑、吞咽困难,无咳嗽、咳痰、憋气,无畏寒、发热,随吞咽上下移动,未诊治,发病后无明显变化。患者既往30年前在当地医院... 1临床资料患者,女,37岁,因“发现颈部肿物3周余”于2020-04-16就诊于我院。患者无意中发现颈部肿物,无疼痛,无声音嘶哑、吞咽困难,无咳嗽、咳痰、憋气,无畏寒、发热,随吞咽上下移动,未诊治,发病后无明显变化。患者既往30年前在当地医院曾行颈部肿物手术(具体术式不详)。 展开更多
关键词 甲状舌管囊肿(Thyroglossal duct cyst) 复发(Recurrence) 多囊(Multiple)
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Role of copper in central nervous system physiology and pathology 被引量:2
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作者 Martina Locatelli Cinthia Farina 《Neural Regeneration Research》 SCIE CAS 2025年第4期1058-1068,共11页
Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central ne... Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central nervous system.Central copper dysregulations have been evidenced in two genetic disorders characterized by mutations in the copper-ATPases ATP7A and ATP7B,Menkes disease and Wilson’s disease,respectively,and also in multifactorial neurological disorders such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and multiple sclerosis.This review summarizes current knowledge about the role of copper in central nervous system physiology and pathology,reports about unbalances in copper levels and/or distribution under disease,describes relevant animal models for human disorders where copper metabolism genes are dysregulated,and discusses relevant therapeutic approaches modulating copper availability.Overall,alterations in copper metabolism may contribute to the etiology of central nervous system disorders and represent relevant therapeutic targets to restore tissue homeostasis. 展开更多
关键词 ASTROCYTES central nervous system COPPER CUPRIZONE multiple sclerosis MYELIN neurodegenerative disorders
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Unraveling brain aging through the lens of oral microbiota 被引量:1
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作者 Qinchao Hu Si Wang +2 位作者 Weiqi Zhang Jing Qu Guang-Hui Liu 《Neural Regeneration Research》 SCIE CAS 2025年第7期1930-1943,共14页
The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even... The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative diseases.Recent studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention strategies.In this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and neurodegeneration.We also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging. 展开更多
关键词 Alzheimer's disease brain aging multiple sclerosis NEURODEGENERATION neurodegenerative diseases oral microbiota Parkinson's disease PERIODONTITIS BACTERIA Porphyromonas gingivalis
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Association of interleukin-6 with acute lung injury risk and disease severity in sepsis 被引量:1
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作者 Imshaal Musharaf Abdulqadir J Nashwan 《World Journal of Clinical Cases》 SCIE 2025年第8期49-52,共4页
Sepsis is a life-threatening condition caused by a dysregulated response of the body in response to an infection that harms its tissues and organs.Interleukin-6(IL-6)is a significant component of the inflammatory resp... Sepsis is a life-threatening condition caused by a dysregulated response of the body in response to an infection that harms its tissues and organs.Interleukin-6(IL-6)is a significant component of the inflammatory response as part of the pa-thogenesis of sepsis.It aids in the development of Acute lung injury and,subse-quently,multiple organ dysfunction syndrome.This letter probes into the corre-lation between plasma IL-6 levels and the risk of developing acute lung injury and multiple organ dysfunction syndrome in critically ill patients with sepsis.While it shows promising results,limitations like its observational study design,a limited sample size,a single center involvement,single-time-point measurement,and a lack of a control group restrain its cogency.The study is a big step in identifying IL-6 as a biomarker to improve patient care. 展开更多
关键词 SEPSIS Acute lung injury Multiple organ dysfunction syndrome INTERLEUKIN-6 BIOMARKER Critical illness
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Multiplicities of fixed points of holomorphic maps in several complex variables 被引量:1
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作者 张广远 《Science China Mathematics》 SCIE 2001年第3期330-337,共8页
Let Δυ be the unit ball in ?υ with center 0 (the origin of υ) and let F:Δυ→?υbe a holomorphic map withF(0) = 0. This paper is to study the fixed point multiplicities at the origin 0 of the iteratesF i =F°... Let Δυ be the unit ball in ?υ with center 0 (the origin of υ) and let F:Δυ→?υbe a holomorphic map withF(0) = 0. This paper is to study the fixed point multiplicities at the origin 0 of the iteratesF i =F°?°F (i times),i = 1,2,.... This problem is easy when υ = 1, but it is very complicated when υ > 1. We will study this problem generally. 展开更多
关键词 holomorphic maps complex dynamical systems multiplicities of fixed points
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Multiple primary cancers with gastrointestinal malignant tumors as the first manifestation:Three case reports and review of literature 被引量:1
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作者 Xin-Ran Bi Shuang-Yan Zhao +4 位作者 Yu-Qi Ma Xiao-Yu Duan Ting-Ting Hu Lian-Zhu Bi Hong-Yi Cai 《World Journal of Gastroenterology》 2025年第8期130-139,共10页
BACKGROUND The incidence of malignant gastrointestinal(GI)tumors is increasing,and advancements in medical care have significantly improved patient survival rates.As a result,the number of cases involving multiple pri... BACKGROUND The incidence of malignant gastrointestinal(GI)tumors is increasing,and advancements in medical care have significantly improved patient survival rates.As a result,the number of cases involving multiple primary cancers(MPC)has also increased.The rarity of MPC and the absence of sensitive and specific dia-gnostic markers often lead to missed or incorrect diagnoses.It is,therefore,of vital importance to improve the vigilance of clinicians and the accurate diagnosis of this disease.Patients with GI malignancies face a higher relative risk of deve-loping additional primary malignant tumors compared to those with other systemic tumors.Vigilant monitoring and follow-up are crucial,especially for high-risk groups,which include older adults,men,those with addictions to alcohol and tobacco,those with a family history of tumors,and those who have undergone radiotherapy.CASE SUMMARY In this article,we report three cases of MPC,each involving malignant tumors of the GI tract as the initial primary carcinoma,offering insights that may aid in effectively managing similar cases.CONCLUSION Patients with GI malignancies face a higher MPC risk.Developing screening and follow-up protocols may enhance detection and treatment outcomes. 展开更多
关键词 Multiple primary cancer Gastrointestinal tract SYNCHRONOUS METACHRONOUS Case report
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Wetland and habitat dynamics in the evolving landscape of the Middle Yangtze River Basin 被引量:1
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作者 YANG Peng SUN Kaiya +5 位作者 ZHU Yanchao XIA Jun HUANG Heqing SONG Jingxia SHI Xiaorui LU Xixi 《Journal of Geographical Sciences》 2025年第1期88-111,共24页
Wetlands play a critical role in the global environment.The Middle Yangtze River Basin(MYRB),known for its abundant wetland resources,has experienced notable changes resulting from the complex interplay of environment... Wetlands play a critical role in the global environment.The Middle Yangtze River Basin(MYRB),known for its abundant wetland resources,has experienced notable changes resulting from the complex interplay of environmental factors.Therefore,we investigated the spatiotemporal characteristics of wetland ecological quality in the MYRB from 2001 to 2020.Utilizing the random forest(RF)regression algorithm and patch-generated land-use simulation(PLUS)model,we forecasted variations in wetland habitat quality and their determinants under the Shared Socioeconomic Pathway-Representative Concentration Pathway(SSPRCP)framework from 2035 to 2095.The main findings are as follows:(1)The RF algorithm was optimal for land-use and land-cover(LULC)classification in the MYRB from 2001 to 2020,when notable changes were observed in water bodies and buildings.However,the forested area exhibited an increase and decrease of 3.9%and 1.2%under the SSP1-2.6 and SSP5-8.5 scenarios,respectively,whereas farmland exhibited a diminishing trend.(2)Wetlands were primarily concentrated in the central and eastern MYRB,with counties in the southwest exhibiting superior ecological-environmental quality from 2001 to 2020.Notably,wetland coverage revealed significantly high level,significant changes,frequent but relatively minor changes under the SSP1-2.6,SSP2-4.5,and SSP 5-8.5 scenarios,respectively.(3)Regions with lower habitat quality were primarily concentrated in urbanized areas characterized by frequent human activities,indicating a clear degradation in habitat quality across different scenarios.In conclusion,we established a foundational framework for future investigations into the eco-hydrological processes and ecosystem quality of watersheds. 展开更多
关键词 Middle Yangtze River Basin WETLAND environmental change habitat quality multiple scenarios
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Perturbation response scanning of drug-target networks:Drug repurposing for multiple sclerosis 被引量:1
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作者 Yitan Lu Ziyun Zhou +10 位作者 Qi Li Bin Yang Xing Xu Yu Zhu Mengjun Xie Yuwan Qi Fei Xiao Wenying Yan Zhongjie Liang Qifei Cong Guang Hu 《Journal of Pharmaceutical Analysis》 2025年第6期1277-1290,共14页
Combined with elastic network model(ENM),the perturbation response scanning(PRS)has emerged as a robust technique for pinpointing allosteric interactions within proteins.Here,we proposed the PRS analysis of drug-targe... Combined with elastic network model(ENM),the perturbation response scanning(PRS)has emerged as a robust technique for pinpointing allosteric interactions within proteins.Here,we proposed the PRS analysis of drug-target networks(DTNs),which could provide a promising avenue in network medicine.We demonstrated the utility of the method by introducing a deep learning and network perturbation-based framework,for drug repurposing of multiple sclerosis(MS).First,the MS comorbidity network was constructed by performing a random walk with restart algorithm based on shared genes between MS and other diseases as seed nodes.Then,based on topological analysis and functional annotation,the neurotransmission module was identified as the“therapeutic module”of MS.Further,perturbation scores of drugs on the module were calculated by constructing the DTN and introducing the PRS analysis,giving a list of repurposable drugs for MS.Mechanism of action analysis both at pathway and structural levels screened dihydroergocristine as a candidate drug of MS by targeting a serotonin receptor of se-rotonin 2B receptor(HTR2B).Finally,we established a cuprizone-induced chronic mouse model to evaluate the alteration of HTR2B in mouse brain regions and observed that HTR2B was significantly reduced in the cuprizone-induced mouse cortex.These findings proved that the network perturbation modeling is a promising avenue for drug repurposing of MS.As a useful systematic method,our approach can also be used to discover the new molecular mechanism and provide effective candidate drugs for other complex diseases. 展开更多
关键词 Network perturbations Mechanism of action Multiple sclerosis HTR2B
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Resource Allocation for RSMA-Aided Multibeam Satellite Communications 被引量:1
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作者 Cui Huanxi Xiao Zhenyu Zhu Lipeng 《China Communications》 2025年第2期241-255,共15页
This paper investigates the resource allocation for rate-splitting multiple access(RSMA)enabled multibeam satellite communication systems.Specifically,we minimize the total unmet user rate,which denotes the difference... This paper investigates the resource allocation for rate-splitting multiple access(RSMA)enabled multibeam satellite communication systems.Specifically,we minimize the total unmet user rate,which denotes the difference between the users’rate requirement and the practical achievable rate,as well as the total transmit power of the satellite by optimizing the precoding,power allocation,and rate allocation,under the per-feed power and rate constraints.To solve the non-convex optimization problem,a twostage scheme is proposed.In particular,in the first stage,we present a precoding scheme by maximizing the signal-to-leakage-plus-noise ratio of each beam to eliminate the inter-beam interference.In the second stage,we introduce auxiliary variables to obtain an upper bound on the objective function under the given precoding matrix and transform the rate constraints of the original problem into second-order cones(SOC)and linear matrix inequations(LMI).Then,the successive convex approximation(SCA)technique is used to obtain suboptimal power and rate allocation solutions.Moreover,the initial feasible solution for power allocation is provided by using the standard interior point method.Finally,numerical results verify the superiority of our proposed solution compared to the benchmark methods in terms of objective function values. 展开更多
关键词 multibeam satellite power allocation PRECODING rate allocation rate-splitting multiple access(RSMA)
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Irreversibility analysis and multiple cubic regression based efficiency evaluation of ternary nanofluids(TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O)via converging/diverging channels 被引量:1
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作者 Siddhant Taneja Sapna Sharma Bhuvaneshvar Kumar 《Acta Mechanica Sinica》 2025年第6期63-75,共13页
This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to d... This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production,while ensuring cost efficiency.This work bridges the gap be-tween academic research and industrial feasibility by incorporating cost analysis,entropy generation,and thermal efficiency.To compare the velocity,temperature,and concentration profiles,we examine two ternary nanofluids,i.e.,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O,while considering the shape of nanoparticles.The velocity slip and Soret/Dufour effects are taken into consideration.Furthermore,regression analysis for Nusselt and Sherwood numbers of the model is carried out.The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations.The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluc-tuation of flow-dominating parameters.Additionally,the influence of these parameters is demonstrated in the flow,temperature,and concentration fields.For variation in Eckert and Dufour numbers,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher temperature than TiO_(2)+SiO_(2)+Cu/H_(2)O.The results obtained indicate that the ternary nanofluid TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher heat transfer rate,lesser entropy generation,greater mass transfer rate,and lower cost than that of TiO_(2)+SiO_(2)+Cu/H_(2)O ternary nanofluid. 展开更多
关键词 Converging/Diverging channels Ternary nanofluids Multiple cubic regression Entropy generation
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Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies
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作者 Guangyong Zhang Qing Yao +9 位作者 Chubing Long Pengcheng Yi Jiali Song Luojia Wu Wei Wan Xiuqin Rao Yue Lin Gen Wei Jun Ying Fuzhou Hua 《Neural Regeneration Research》 SCIE CAS 2025年第3期779-793,共15页
Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple rol... Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases. 展开更多
关键词 blood–brain barrier MACROPHAGES MONOCYTES multiple sclerosis NEUROINFLAMMATION review therapy
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Oligodendroglial heterogeneity in health,disease,and recovery:deeper insights into myelin dynamics
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作者 Pieter-Jan Serneels Julie D.De Schutter +2 位作者 Lies De Groef Lieve Moons Steven Bergmans 《Neural Regeneration Research》 SCIE CAS 2025年第11期3179-3192,共14页
Decades of research asserted that the oligodendroglial lineage comprises two cell types:oligodendrocyte precursor cells and oligodendrocytes.However,recent studies employing single-cell RNA sequencing techniques have ... Decades of research asserted that the oligodendroglial lineage comprises two cell types:oligodendrocyte precursor cells and oligodendrocytes.However,recent studies employing single-cell RNA sequencing techniques have uncovered novel cell states,prompting a revision of the existing terminology.Going forward,the oligodendroglial lineage should be delineated into five distinct cell states:oligodendrocyte precursor cells,committed oligodendrocyte precursor cells,newly formed oligodendrocytes,myelin-forming oligodendrocytes,and mature oligodendrocytes.This new classification system enables a deeper understanding of the oligodendroglia in both physiological and pathological contexts.Adopting this uniform terminology will facilitate comparison and integration of data across studies.This,including the consolidation of findings from various demyelinating models,is essential to better understand the pathogenesis of demyelinating diseases.Additionally,comparing injury models across species with varying regenerative capacities can provide insights that may lead to new therapeutic strategies to overcome remyelination failure.Thus,by standardizing terminology and synthesizing data from diverse studies across different animal models,we can enhance our understanding of myelin pathology in central nervous system disorders such as multiple sclerosis,Alzheimer's disease,and amyotrophic lateral sclerosis,all of which involve oligodendroglial and myelin dysfunction. 展开更多
关键词 animal models DEMYELINATION fish MAMMALS multiple sclerosis MYELIN neurodegeneration OLIGODENDROCYTES oligodendroglial lineage REMYELINATION
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Novel homozygous SPAG17 variants cause human male infertility through multiple morphological abnormalities of spermatozoal flagella related to axonemal microtubule doublets 被引量:1
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作者 Tao Liu Fazal Rahim +15 位作者 Meng-Lei Yang Meftah Uddin Jing-Wei Ye Imtiaz Ali Yousaf Raza Abu Mansoor Muhammad Shoaib Mujahid Hussain Ihsan Khan Basit Shah Asad Khan Ahmad Nisar Hui Ma Bo Xu Wasim Shah Qing-Hua Shi 《Asian Journal of Andrology》 2025年第2期245-253,共9页
Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella(MMAF).Distinct projections encircling the central microtubules of the spermatozoal axoneme play p... Male infertility can result from impaired sperm motility caused by multiple morphological abnormalities of the flagella(MMAF).Distinct projections encircling the central microtubules of the spermatozoal axoneme play pivotal roles in flagellar bending and spermatozoal movement.Mammalian sperm-associated antigen 17(SPAG17)encodes a conserved axonemal protein of cilia and flagella,forming part of the C1a projection of the central apparatus,with functions related to ciliary/flagellar motility,skeletal growth,and male fertility.This study investigated two novel homozygous SPAG17 mutations(M1:NM_206996.2,c.829+1G>T,p.Asp212_Glu276del;and M2:c.2120del,p.Leu707*)identified in four infertile patients from two consanguineous Pakistani families.These patients displayed the MMAF phenotype confirmed by Papanicolaou staining and scanning electron microscopy assays of spermatozoa.Quantitative real-time polymerase chain reaction(PCR)of patients’spermatozoa also revealed a significant decrease in SPAG17 mRNA expression,and immunofluorescence staining showed the absence of SPAG17 protein signals along the flagella.However,no apparent ciliary-related symptoms or skeletal malformations were observed in the chest X-rays of any of the patients.Transmission electron microscopy of axoneme cross-sections from the patients showed incomplete C1a projection and a higher frequency of missing microtubule doublets 1 and 9 compared with those from fertile controls.Immunofluorescence staining and Western blot analyses of spermatogenesis-associated protein 17(SPATA17),a component of the C1a projection,and sperm-associated antigen 6(SPAG6),a marker of the spring layer,revealed disrupted expression of both proteins in the patients’spermatozoa.Altogether,these findings demonstrated that SPAG17 maintains the integrity of spermatozoal flagellar axoneme,expanding the phenotypic spectrum of SPAG17 mutations in humans. 展开更多
关键词 C1a projection central apparatus male infertility multiple morphological abnormalities of the flagella SPAG17
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In situ stress inversion using nonlinear stress boundaries achieved by the bubbling method 被引量:1
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作者 Xige Liu Chenchun Huang +3 位作者 Wancheng Zhu Joung Oh Chengguo Zhang Guangyao Si 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1510-1527,共18页
Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this cha... Due to the heterogeneity of rock masses and the variability of in situ stress,the traditional linear inversion method is insufficiently accurate to achieve high accuracy of the in situ stress field.To address this challenge,nonlinear stress boundaries for a numerical model are determined through regression analysis of a series of nonlinear coefficient matrices,which are derived from the bubbling method.Considering the randomness and flexibility of the bubbling method,a parametric study is conducted to determine recommended ranges for these parameters,including the standard deviation(σb)of bubble radii,the non-uniform coefficient matrix number(λ)for nonlinear stress boundaries,and the number(m)and positions of in situ stress measurement points.A model case study provides a reference for the selection of these parameters.Additionally,when the nonlinear in situ stress inversion method is employed,stress distortion inevitably occurs near model boundaries,aligning with the Saint Venant's principle.Two strategies are proposed accordingly:employing a systematic reduction of nonlinear coefficients to achieve high inversion accuracy while minimizing significant stress distortion,and excluding regions with severe stress distortion near the model edges while utilizing the central part of the model for subsequent simulations.These two strategies have been successfully implemented in the nonlinear in situ stress inversion of the Xincheng Gold Mine and have achieved higher inversion accuracy than the linear method.Specifically,the linear and nonlinear inversion methods yield root mean square errors(RMSE)of 4.15 and 3.2,and inversion relative errors(δAve)of 22.08%and 17.55%,respectively.Therefore,the nonlinear inversion method outperforms the traditional multiple linear regression method,even in the presence of a systematic reduction in the nonlinear stress boundaries. 展开更多
关键词 In situ stress field Inversion method The bubbling method Nonlinear stress boundary Multiple linear regression method
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