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On Intersection Multiplicity of Algebraic Curves
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作者 LIANG Hong-Chang 《Chinese Quarterly Journal of Mathematics》 2019年第1期14-20,共7页
In this paper, we study the intersection multiplicity of algebraic curves at a point both in R^2 and in real projective plane P^2. We introduce the fold point of curves and provide conditions for the relations between... In this paper, we study the intersection multiplicity of algebraic curves at a point both in R^2 and in real projective plane P^2. We introduce the fold point of curves and provide conditions for the relations between the intersection multiplicity of curves at a point and the folds of the point. 展开更多
关键词 algebraic CURVES INTERSECTION multiplicity PROJECTIVE transformation d-fold point
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Passive neutron multiplicity device for^(240)Pu measurement based on FPGA
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作者 Yan Zhang Hao-Ran Zhang +6 位作者 Ren-Bo Wang Ming-Yu Li Rui Chen Hai-Tao Wang Xiang-Ting Meng Shu-Min Zhou Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期141-154,共14页
A passive neutron multiplicity measurement device,FH-NCM/S1,based on field-programmable gate arrays(FPGAs),is developed specifically for measuring the mass of plutonium-240(^(240)Pu)in mixed oxide fuel.FH-NCM/S1 adopt... A passive neutron multiplicity measurement device,FH-NCM/S1,based on field-programmable gate arrays(FPGAs),is developed specifically for measuring the mass of plutonium-240(^(240)Pu)in mixed oxide fuel.FH-NCM/S1 adopts an inte-grated approach,combining the shift register analysis mode with the pulse-position timestamp mode using an FPGA.The optimal effective length of the^(3)He neutron detector was determined to be 30 cm,and the thickness of the graphite reflector was ascertained to be 15 cm through MCNP simulations.After fabricating the device,calibration measurements were per-formed using a^(252)Cf neutron source;a detection efficiency of 43.07%and detector die-away time of 55.79μs were observed.Nine samples of plutonium oxide were measured under identical conditions using the FH-NCM/S1 in shift register analysis mode and a plutonium waste multiplicity counter.The obtained double rates underwent corrections for detection efficiency(ε)and double gate fraction(f_(d)),resulting in corrected double rates(D_(c)),which were used to validate the accuracy of the shift register analysis mode.Furthermore,the device exhibited fluctuations in the measurement results,and within a single 20 s measurement,these fluctuations remained below 10%.After 30 cycles,the relative error in the mass of^(240)Pu was less than 5%.Finally,correlation calculations confirmed the robust consistency of both measurement modes.This study holds specific significance for the subsequent design and development of neutron multiplicity devices. 展开更多
关键词 Spent fuel Non-destructive assay Neutron multiplicity ^(240)Pu FPGA
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FINITE RANGE SET WITH TRUNCATED MULTIPLICITY FOR MEROMORPHIC FUNCTIONS ON SOME COMPLEX DISC
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作者 WANG Yu-ting CAO Hong-zhe 《数学杂志》 2024年第5期383-396,共14页
In this paper,we consider the truncated multiplicity finite range set problem of meromorphic functions on some complex disc.By using the value distribution theory of meromorphic functions,we establish a second main th... In this paper,we consider the truncated multiplicity finite range set problem of meromorphic functions on some complex disc.By using the value distribution theory of meromorphic functions,we establish a second main theorem for meromorphic functions with finite growth index which share meromorphic functions(may not be small functions).As its application,we also extend the result of a finite range set with truncated multiplicity. 展开更多
关键词 meromorphic functions finite growth index complex disc finite range set trun-cated multiplicity
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The Njiki’s Fundamental Theorem-Definition on Fractions in the Mathematical Set ℚ and by Extension in ℝ and ℂ, for the Purpose of Leading to the Construction of Some Algebraic Structures as Its Theoretical Applications and for the Practical Ones
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作者 Jean Claude Njiki 《American Journal of Computational Mathematics》 2024年第3期358-379,共22页
The purpose of the research in the NJIKI’s fundamental THEOREM-DEFINITION on fractions in the mathematical set ℚand by extension in ℝand ℂand in order to construct some algebraic structures is about the proved EXISTE... The purpose of the research in the NJIKI’s fundamental THEOREM-DEFINITION on fractions in the mathematical set ℚand by extension in ℝand ℂand in order to construct some algebraic structures is about the proved EXISTENCE and the DEFINITION by NJIKI of two INNOVATIVE, IMPORTANT and TEACHABLE operations of addition or additive operations, in ℚ, marked ⊕and +α,β, and taken as VECTORIAL, TRIANGULAR, of THREE or PROPORTIONAL operations and in order to make THEM not be different from the RATIONAL ONE, +, but to bring much more and new information on fractions, and, by extension in ℝand ℂ. And the very NJIKI’s fundamental THEOREM-DEFINITION having many APPLICATIONS in the everyday life of the HUMAN BEINGS and without talking about computer sciences, henceforth being supplied with very interesting new ALGORITHMS. And as for the work done in the research, it will be waiting for its extension to be done after publication and along with the research results concerned. 展开更多
关键词 Operations of Addition Additive Operations in Laws in THEOREM-DEFINITION External Multiplication
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Comparative Study on the Policy of Multiplicity Issues in Clinical Trials at Home and Abroad
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作者 Gong Jingran Chang Yingnan +1 位作者 Qiao Jiahui Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第1期43-49,共7页
Objective To study the content of China’s guiding principles on multiplicity issues in clinical trials,and to provide reference for the revision of China’s relevant guiding principles.Methods Based on ICH E9,the sim... Objective To study the content of China’s guiding principles on multiplicity issues in clinical trials,and to provide reference for the revision of China’s relevant guiding principles.Methods Based on ICH E9,the similarities and differences of the guiding principles of US Food and Drug Administration(FDA),European Medicines Agency(EMA),and National Medical Products Administration(NMPA)on the multiplicity issues in clinical trials were compared one by one.Results and Conclusion In general,NMPA guidelines are based on ICH E9,but in detail,the guidelines of FDA and EMA focus differently on the multiplicity issues.Therefore,NMPA guidelines need to be detailed and comprehensive.NMPA guidelines can be refined by referring to foreign guidelines to improve the practical guiding significance for clinical research and promote the level of domestic clinical trials in line with international standards. 展开更多
关键词 clinical trial multiplicity issue solution strategy
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On the growth of transcendental entire solutions of algebraic differential equations 被引量:2
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作者 朱玲妹 杨德贵 王小灵 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期98-102,共5页
In this paper, we investigate the growth of transcendental entire solutionsof the following algebraic differential equation a(z)f'~2 +(b_2(z)f^2 +b_1(z)f +b_0(z))f'=d_3(z)f^3+d_2(z)f^2 +d_1(z)f +d_0(z), where ... In this paper, we investigate the growth of transcendental entire solutionsof the following algebraic differential equation a(z)f'~2 +(b_2(z)f^2 +b_1(z)f +b_0(z))f'=d_3(z)f^3+d_2(z)f^2 +d_1(z)f +d_0(z), where a(z), b_i(z) (0<- i <=2) and d_j (z) (0<=j<= 3) are allpolynomials, and this equation relates closely to the following well-known algebraic differentialequation C(z,w)w'~2 + B(z,w)w' + A(z,w) =0, where G(z,w)not ident to 0, B(z,w) and A(z,w) are threepolynomials in z and w. We give relationships between the growth of entire solutions and the degreesof the above three polynomials in detail. 展开更多
关键词 algebraic differential equation DEGREE entire solutions
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Algebraic Structure of the Dynamical Equations of Holonomic Mechanical System in Relative Motion 被引量:2
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作者 张毅 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期12-18,共7页
Aim To study an algebraic of the dynamical equations of holonomic mechanical systems in relative motion. Methods The equations of motion were presented in a contravariant algebraic form and an algebraic product was... Aim To study an algebraic of the dynamical equations of holonomic mechanical systems in relative motion. Methods The equations of motion were presented in a contravariant algebraic form and an algebraic product was determined. Results and Conclusion The equations a Lie algebraic structure if any nonpotential generalized force doesn't exist while while the equations possess a Lie-admissible algebraic structure if nonpotential generalized forces exist . 展开更多
关键词 analytical mechanics holonomic system relative motion Lie-admissible algebra
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Algebraic processing technique for extracting frequency-dependent shear-wave splitting parameters in an anisotropic medium 被引量:1
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作者 韩开锋 曾新吾 《Applied Geophysics》 SCIE CSCD 2011年第2期134-140,177,共8页
Based on the dual source cumulative rotation technique in the time-domain proposed by Zeng and MacBeth(1993),a new algebraic processing technique for extracting shear-wave splitting parameters from multi-component V... Based on the dual source cumulative rotation technique in the time-domain proposed by Zeng and MacBeth(1993),a new algebraic processing technique for extracting shear-wave splitting parameters from multi-component VSP data in frequency-dependent medium has been developed.By using this dual source cumulative rotation technique in the frequency-domain(DCTF),anisotropic parameters,including polarization direction of the shear-waves and timedelay between the fast and slow shear-waves,can be estimated for each frequency component in the frequency domain.It avoids the possible error which comes from using a narrow-band filter in the current commonly used method.By using synthetic seismograms,the feasibility and validity of the technique was tested and a comparison with the currently used method was also given.The results demonstrate that the shear-wave splitting parameters frequency dependence can be extracted directly from four-component seismic data using the DCTF.In the presence of larger scale fractures,substantial frequency dependence would be found in the seismic frequency range,which implies that dispersion would occur at seismic frequencies.Our study shows that shear-wave anisotropy decreases as frequency increases. 展开更多
关键词 algebraic processing technique ANISOTROPY shear-wave splitting frequency dependence
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社区慢性病共病药物治疗决策的困境与应对路径 被引量:1
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作者 夏瑀 罗原 +4 位作者 李峥嵘 周馨媚 童钰铃 赵洋 徐志杰 《中国全科医学》 CAS 北大核心 2025年第1期103-110,118,共9页
慢性病共病是指个体同时患有2种及以上的慢性疾病。共病患者常联用多种药物治疗,给社区全科医生的科学用药决策带来了挑战。本文分析了社区共病药物治疗决策困境形成的原因与影响因素,并提出了一种动态的综合性决策框架,即共病药物治疗... 慢性病共病是指个体同时患有2种及以上的慢性疾病。共病患者常联用多种药物治疗,给社区全科医生的科学用药决策带来了挑战。本文分析了社区共病药物治疗决策困境形成的原因与影响因素,并提出了一种动态的综合性决策框架,即共病药物治疗决策框架(MDMF)。该框架由社区全科医生接诊共病患者的5个阶段构成,包括“健康问题回顾”“用药综合评估”“医患共同决策”“药物治疗记录”和“安排随访计划”。MDMF能够促使社区全科医生为共病患者制定个体化的药物治疗方案,但也对其诊疗能力提出了一定要求。因此,建议对社区全科医生开展以MDMF为核心的培训、提供决策辅助支持,并采取合理的激励与监督措施,推动社区医疗机构提供以患者为中心的药物治疗方案,提升药物治疗的安全性和有效性,减轻患者的治疗负担。 展开更多
关键词 慢性病共病 药物治疗决策 决策模型 社区卫生服务 全科医生
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Vibrational Spectra of Nonrigid Molecule HCP in an Algebraic Model
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作者 侯喜文 乔安钦 成传明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第6期478-480,共3页
An algebraic Harniltonian for the two coupled nonlinear vibrations of highly excited nonrigid molecule HCP was presented. The Hamiltonian reduces to the conventional one in a limit which was expressed in terms of harm... An algebraic Harniltonian for the two coupled nonlinear vibrations of highly excited nonrigid molecule HCP was presented. The Hamiltonian reduces to the conventional one in a limit which was expressed in terms of harmonic oscillator operators. It showed that the algebraic model can better reproduce the data than the conventional model by fitting the observed data of HCP. 展开更多
关键词 Vibrational energy levels algebraic methods Fermi resonances
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Role of copper in central nervous system physiology and pathology
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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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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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Extramedullary plasmacytoma with the uvula as first affected site:A case report
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作者 Jing Yang Hui Peng +2 位作者 Sheng-Ke Tu Min Li Kui Song 《World Journal of Clinical Oncology》 2025年第1期53-58,共6页
BACKGROUND Extramedullary plasmacytoma(EMP)represents one of the rarer forms of plasma cell malignancies,capable of impacting a variety of tissues and organs throughout the body.The majority of EMP cases are predomina... BACKGROUND Extramedullary plasmacytoma(EMP)represents one of the rarer forms of plasma cell malignancies,capable of impacting a variety of tissues and organs throughout the body.The majority of EMP cases are predominantly found in the head and neck region,especially within the laryngopharynx,as well as in the gastrointestinal tract.While there have been documented instances of oropharyngeal involvement in EMP cases in the academic literature,it is important to note that EMP specifically affecting the uvula is exceedingly uncommon.Furthermore,it is noteworthy that over 60% of epithelial carcinomas in the upper respiratory tract and oropharynx tend to metastasize to the cervical lymph nodes,indicating a propensity for regional spread in these types of cancers.In this context,we present a rare case of extramedullary plasmacytoma where the uvula served as the initially affected site.This case emphasizes the need for heightened awareness among clinicians regarding such unusual comorbidities,as early recognition and diagnosis can significantly influence patient management and treatment outcomes.In addition,a review of the relevant literature is included to further educate and inform healthcare professionals about this rare presentation,ultimately aiming to enhance clinical understanding and improve patient care in similar situations.CASE SUMMARY A 51-year-old man was admitted to our hospital because of a slowly enlarging neck mass.A physical examination revealed a palpable left lymph node,and magnetic resonance imaging(MRI)of the oropharynx and the neck showed a soft tissue mass in the oropharynx and enlargement of multiple lymph nodes in the neck.The soft tissue mass was diagnosed as plasmacytoma by immunohistochemical analysis.Monoclonal immunoglobulins and bone marrow biopsy showed normal results.Therefore,we diagnosed that as EMP of the uvula.After four cycles of adjuvant chemotherapy dominated by bortezomib,MRI reexamination showed a significant reduction of the mass in the oropharynx and the cervical lymph nodes.Afterwards,the λ light chain returned to normal levels.There was no evidence of evolution to multiple myeloma.CONCLUSION We have reported a rare case of extramedullary plasmacytoma with the uvula as the first affected site and the relevant literature is reviewed to improve clinicians'awareness of such rare comorbidities. 展开更多
关键词 Extramedullary plasmacytoma PLASMACYTOMA UVULA Multiple myeloma Case report
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Unraveling brain aging through the lens of oral microbiota
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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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Pulp health and calcific healing of a complicated crown–root fracture with additional root fracture in a maxillary incisor: A case report
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作者 Na Li Yue-Yue Ren +4 位作者 Ying Tang Qi Yang Tian-Tian Meng Song Li Jing Zhang 《World Journal of Clinical Cases》 SCIE 2025年第3期42-49,共8页
BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and te... BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and teenagers, but the maintenance of pulphealth and the calcific healing of multiple root fractures are rarely reported in theliterature.CASE SUMMARY This case reports healing of a permanent tooth with complicated crown–root andadditional root fractures, in which pulp health was maintained. A 10-year-old girlfell and fractured the root of her maxillary left central incisor at the cervical level.After the coronal fragment was repositioned, the tooth was splinted until thetooth was no longer mobile, 2 years later. Eight years after treatment, the toothhas remained asymptomatic with vital pulp and localized gingival overgrowth.Cone-beam computed tomography revealed not only calcified healing of the CRFbut also spontaneous healing in an additional undiagnosed root fracture. Thefracture line on the enamel could not be healed by hard tissue and formed agroove in the cervical crown. It was speculated that the groove was related to thelocalized gingival overgrowth.CONCLUSION This case provides a clinical perspective of the treatment of a tooth with acomplicated CRF and an additional root fracture. 展开更多
关键词 Complicated crown-root fracture Multiple root fracture Spontaneous healing Cone-beam computed tomography Long-term follow-up Case report
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Copper homeostasis and neurodegenerative diseases
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作者 Yuanyuan Wang Daidi Li +2 位作者 Kaifei Xu Guoqing Wang Feng Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第11期3124-3143,共20页
Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of concentrations.Copper homeostasis is... Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of concentrations.Copper homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting beta(ATP7B),and the three copper chaperones ATOX1,CCS,and COX17.Disruptions in copper homeostasis can lead to either the deficiency or accumulation of copper in brain tissue.Emerging evidence suggests that abnormal copper metabolism or copper binding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative disorders.However,the exact mechanisms underlying these processes are not known.Copper is a potent oxidant that increases reactive oxygen species production and promotes oxidative stress.Elevated reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial dysfunction.Reactive oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory pathways.Additionally,copper can bind aberrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereby inducing neurotoxicity and ultimately cell death.This study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-binding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease pathogenesis.By synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms by which copper contributes to a wide range of hereditary and neuronal disorders,such as Wilson's disease,Menkes'disease,Alzheimer's disease,Parkinson's disease,amyotrophic lateral sclerosis,Huntington's disease,and multiple sclerosis.Potential clinically significant therapeutic targets,including superoxide dismutase 1,D-penicillamine,and 5,7-dichloro-2-[(dimethylamino)methyl]-8-hydroxyquinoline,along with their associated therapeutic agents,are further discussed.Ultimately,we collate evidence that copper homeostasis may function in the underlying etiology of several neurodegenerative diseases and offer novel insights into the potential prevention and treatment of these diseases based on copper homeostasis. 展开更多
关键词 Alzheimer's disease amyotrophic lateral sclerosis disease copper homeostasis copper toxicity Huntington's disease Menkes'disease multiple sclerosis neurodegenerative disease Parkinson's disease Wilson's disease
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On the First-degree Algebraic Equation of the Generalized Quaternion
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作者 蔡永裕 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期59-64,共6页
In this paper, by using the matrix representation of the generalized quaternion algebra, we discussed solution problem for two classes of the first_degree algebraic equation of the generalized quaternion and obtained ... In this paper, by using the matrix representation of the generalized quaternion algebra, we discussed solution problem for two classes of the first_degree algebraic equation of the generalized quaternion and obtained critical conditions on existence of a unique solution, infinitely many solutions or nonexistence any solution for the two classes algebraic equation. 展开更多
关键词 generalized quaternion first_degree algebraic equation matrix representation
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共病药物治疗决策--全科医生接诊病案研究
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作者 罗原 徐志杰 +5 位作者 夏瑀 石佳娜 蒋志志 周馨媚 赵洋 童钰铃 《中国全科医学》 CAS 北大核心 2025年第1期119-124,共6页
慢性病共病患者常联合使用多种药物,疾病与药物之间潜在的复杂相互作用使全科医生面临着难以合理评估共病药物治疗获益与风险的决策困境。本文以1例在社区卫生服务中心就诊的慢性病共病患者为例,展示和阐述了全科医生运用共病药物治疗... 慢性病共病患者常联合使用多种药物,疾病与药物之间潜在的复杂相互作用使全科医生面临着难以合理评估共病药物治疗获益与风险的决策困境。本文以1例在社区卫生服务中心就诊的慢性病共病患者为例,展示和阐述了全科医生运用共病药物治疗决策框架进行科学决策的过程,并基于阿里阿德涅原则为共病管理过程提出的多阶段目标,分析了全科医生在评估、沟通与制定治疗方案等方面的要点和注意事项。希望本文可以为改善社区慢性病共病药物治疗决策的质量提供借鉴。 展开更多
关键词 慢性病共病 接诊 全科医生 药物治疗决策 病例报告
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基于机器学习的农田土壤抗剪强度参数检测方法研究
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作者 于艳艳 朱龙图 刘鹤 《农机化研究》 北大核心 2025年第1期7-15,共9页
土壤抗剪强度参数包括粘聚力和内摩擦角,是评价土壤侵蚀敏感性和反映耕层耕作性能的重要指标。为实现农田土壤抗剪切强度参数的快速检测,提出了一种基于机器学习的土壤抗剪切强度参数检测方法。以STM32单片机为核心处理器,采用圆锥杆、... 土壤抗剪强度参数包括粘聚力和内摩擦角,是评价土壤侵蚀敏感性和反映耕层耕作性能的重要指标。为实现农田土壤抗剪切强度参数的快速检测,提出了一种基于机器学习的土壤抗剪切强度参数检测方法。以STM32单片机为核心处理器,采用圆锥杆、滚珠丝杆滑台、三角支架等构建土壤数据采集装置,利用DYMH-103柱式压力传感器和FlexiForce薄膜传感器分别检测圆锥杆贯入土壤的锥尖阻力和锥侧压力,采用CSF11土壤水分传感器获取土壤含水率信息,通过多传感器数据特征向量提取构建建模数据集。数据集相关性分析结果表明:土壤抗剪强度参数与锥尖阻力、锥侧压力和土壤含水率之间具有明显相关性。利用蒙特卡罗交叉验证(Monte Carlo Cross Validation,MCCV)剔除了数据集中的4个异常样本;同时,提出了一种ELM-PLSR组合建模算法,以决定系数R^(2)和RPD为评价指标,对比评估了ELM、PLSR和ELM-PLSR 3种不同机器学习模型,结果表明:ELM-PLSR模型预测性能优于ELM模型和PLSR模型;检测粘聚力时,对应的R^(2)、RPD分别为0.919和3.475;检测内摩擦角时,对应的R 2和RPD分别为0.910和3.304。研究结果可为土壤抗剪强度参数快速测量提供参考。 展开更多
关键词 机器学习 土壤抗剪强度 多传感器 特征向量 预测模型
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