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A systematic review of progenitor survival and maturation in Parkinsonian models
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作者 Giulia Comini Eilís Dowd 《Neural Regeneration Research》 SCIE CAS 2025年第11期3172-3178,共7页
Stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell source.Unlike current therapeutic options for patient... Stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell source.Unlike current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to patients.The ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian brain.Because the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March 2024.After screening,76 articles were included in the analysis from which 178 separate transplant studies were identified.From these,graft survival could be assessed in 52 studies and differentiation in 129 studies.Overall,we found that graft survival ranged from<1% to 500% of cells transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients. 展开更多
关键词 cell replacement therapy DIFFERENTIATION embryonic stem cells GRAFT induced pluripotent stem cells Parkinson's disease SURVIVAL TRANSPLANT
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Functions of nuclear factor Y in nervous system development,function and health
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作者 Pedro Moreira Roger Pocock 《Neural Regeneration Research》 SCIE CAS 2025年第10期2887-2894,共8页
Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 y... Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 years,research has revealed that the nuclear factor Y complex controls many aspects of brain development,including differentiation,axon guidance,homeostasis,disease,and most recently regeneration.However,a complete understanding of transcriptional regulatory networks,including how the nuclear factor Y complex binds to specific CCAAT boxes to perform its function remains elusive.In this review,we explore the nuclear factor Y complex’s role and mode of action during brain development,as well as how genomic technologies may expand understanding of this key regulator of gene expression. 展开更多
关键词 axon guidance CCAAT boxes neuronal degeneration neuronal differentiation neuronal regeneration nuclear factor Y complex transcription factor transcriptional regulation
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TARGET INFORMATION DIFFERENTIATING TECHNOLOGY IN INFRARED-RADAR DUAL-MODE GUIDANCE SYSTEM
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作者 杨俊鹏 祝小平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第3期245-249,共5页
An improved target tracking information differentiating system using the neural network to substitute for fuzzy rules is presented for the infrared-radar dual-mode guidance system. Since the neural network training ba... An improved target tracking information differentiating system using the neural network to substitute for fuzzy rules is presented for the infrared-radar dual-mode guidance system. Since the neural network training based on the expert knowledge database is conducted off-line, the benefits for developing real-time tracking capabilities can be obtained. The network outputs the confidence degree denoted by the weight value of target information in the data fusion center according to two input variables of the measurement noise covariance and the tracking filter covariance. Simulation results show that the improved system can differentiate the target tracking information from the seeker fast and accurately. 展开更多
关键词 dual-mode guidance system confidence degree information differentiating
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Diagnostic Value of Dual-Energy CT in Differentiating Malignant and Benign Thyroid Nodules: A Systematic Review and Meta-Analysis 被引量:2
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作者 Kunlin Ye Yongyao Kuang +6 位作者 Jianye Liang Xi Xu Changzheng Shi Qingqing Cheng Zijie Jiang Ziyun Xiang Liangping Luo 《Journal of Biosciences and Medicines》 2021年第4期54-76,共23页
<strong>Objectives:</strong> To evaluate the diagnostic performance of the quantitative iodine parameters, including Iodine Concentration (IC), Normalized Iodine Concentration (NIC), and λ<sub>HU<... <strong>Objectives:</strong> To evaluate the diagnostic performance of the quantitative iodine parameters, including Iodine Concentration (IC), Normalized Iodine Concentration (NIC), and λ<sub>HU</sub>, in distinguishing malignant and benign thyroid nodules. <strong>Methods:</strong> Relevant studies were searched from Web of Science, PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure database and other complementary sources from inception to May 20, 2020. Study selection, data extraction, quality assessment, and data analyses were performed following the Cochrane standards and the PRISMA-DTA guideline. <strong>Results: </strong>Eight studies were included (595 patients with 737 thyroid nodules). The pooled sensitivity, specificity and summary diagnostic odds ratio of IC were 79% (95% CI: 69% - 86%), 76% (95% CI: 65% - 84%) and 11 (95% CI: 5 - 27) respectively;those of NIC were 78% (95% CI: 70% - 85%), 80% (95% CI: 74% - 85%) and 15 (95% CI: 9 - 24) respectively;those of λ<sub>HU</sub> were 80% (95% CI: 71% - 87%), 77% (95% CI: 70% - 83%) and 14 (95% CI: 8 - 24) respectively. <strong>Conclusion: </strong>DECT can be a potential evaluation tool for thyroid nodules. The NIC may be the most sensitive iodine parameter and could be comparable between different DECT machines in thyroid nodule assessment. 展开更多
关键词 THYROID NODULES Differential Diagnosis Dual-Energy CT Iodine Concentration META-ANALYSIS
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Nested Saturated Control of Uncertain Complex Cascade Systems Using Mixed Saturation Levels
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作者 Meng Li Zhigang Zeng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1163-1174,共12页
This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inhe... This study addresses the problem of global asymptotic stability for uncertain complex cascade systems composed of multiple integrator systems and non-strict feedforward nonlinear systems. To tackle the complexity inherent in such structures, a novel nested saturated control design is proposed that incorporates both constant saturation levels and state-dependent saturation levels. Specifically, a modified differentiable saturation function is proposed to facilitate the saturation reduction analysis of the uncertain complex cascade systems under the presence of mixed saturation levels. In addition, the design of modified differentiable saturation function will help to construct a hierarchical global convergence strategy to improve the robustness of control design scheme. Through calculation of relevant inequalities, time derivative of boundary surface and simple Lyapunov function,saturation reduction analysis and convergence analysis are carried out, and then a set of explicit parameter conditions are provided to ensure global asymptotic stability in the closed-loop systems. Finally, a simplified system of the mechanical model is presented to validate the effectiveness of the proposed method. 展开更多
关键词 method SATURATION DIFFERENTIABLE
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Deep Structure Optimization for Incremental Hierarchical Fuzzy Systems Using Improved Differential Evolution Algorithm
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作者 Yue Zhu Tao Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1139-1158,共20页
The optimization of the rule base of a fuzzy logic system (FLS) based on evolutionary algorithm has achievednotable results. However, due to the diversity of the deep structure in the hierarchical fuzzy system (HFS) a... The optimization of the rule base of a fuzzy logic system (FLS) based on evolutionary algorithm has achievednotable results. However, due to the diversity of the deep structure in the hierarchical fuzzy system (HFS) and thecorrelation of each sub fuzzy system, the uncertainty of the HFS’s deep structure increases. For the HFS, a largenumber of studies mainly use fixed structures, which cannot be selected automatically. To solve this problem, thispaper proposes a novel approach for constructing the incremental HFS. During system design, the deep structureand the rule base of the HFS are encoded separately. Subsequently, the deep structure is adaptively mutated basedon the fitness value, so as to realize the diversity of deep structures while ensuring reasonable competition amongthe structures. Finally, the differential evolution (DE) is used to optimize the deep structure of HFS and theparameters of antecedent and consequent simultaneously. The simulation results confirm the effectiveness of themodel. Specifically, the root mean square errors in the Laser dataset and Friedman dataset are 0.0395 and 0.0725,respectively with rule counts of rules is 8 and 12, respectively.When compared to alternative methods, the resultsindicate that the proposed method offers improvements in accuracy and rule counts. 展开更多
关键词 Hierarchical fuzzy system automatic optimization differential evolution regression problem
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A NOTE ON THE GENERAL STABILIZATION OF DISCRETE FEEDBACK CONTROL FOR NON-AUTONOMOUS HYBRID NEUTRAL STOCHASTIC SYSTEMS WITH A DELAY
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作者 冯立超 张春艳 +1 位作者 曹进德 武志辉 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1145-1164,共20页
Discrete feedback control was designed to stabilize an unstable hybrid neutral stochastic differential delay system(HNSDDS) under a highly nonlinear constraint in the H_∞ and exponential forms.Nevertheless,the existi... Discrete feedback control was designed to stabilize an unstable hybrid neutral stochastic differential delay system(HNSDDS) under a highly nonlinear constraint in the H_∞ and exponential forms.Nevertheless,the existing work just adapted to autonomous cases,and the obtained results were mainly on exponential stabilization.In comparison with autonomous cases,non-autonomous systems are of great interest and represent an important challenge.Accordingly,discrete feedback control has here been adjusted with a time factor to stabilize an unstable non-autonomous HNSDDS,in which new Lyapunov-Krasovskii functionals and some novel technologies are adopted.It should be noted,in particular,that the stabilization can be achieved not only in the routine H_∞ and exponential forms,but also the polynomial form and even a general form. 展开更多
关键词 hybrid neutral stochastic differential delay system discrete feedback control general stabilization polynomial stabilization
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Systemic lupus erythematosus in a 15-year-old female with multiple splenic nodules:A case report
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作者 Mi Il Kang Hyeok Chan Kwon 《World Journal of Clinical Cases》 SCIE 2024年第12期2128-2133,共6页
BACKGROUND Systemic lupus erythematosus(SLE)is a chronic inflammatory disease primarily affecting young females.SLE can invade any organ,and various forms of splenic invasion have been reported.Manifestations include ... BACKGROUND Systemic lupus erythematosus(SLE)is a chronic inflammatory disease primarily affecting young females.SLE can invade any organ,and various forms of splenic invasion have been reported.Manifestations include splenomegaly and splenic infarction,rupture,and calcification.The study encountered a rare case of splenic involvement,with nodules of various sizes without calcifications or ruptures.CASE SUMMARY A 15-year-old girl presented with arthralgia,weight loss,fever,increased levels of inflammatory markers,and positive antinuclear antibody test results.The patient was diagnosed with SLE.She was asymptomatic while taking steroids and hydroxychloroquine.Ten months after discharge,the patient developed a fever and abdominal pain.Lupus enteritis was suspected,and abdominopelvic computed tomography(AP-CT)was performed.There were no specific findings in the gastrointestinal tract,but multiple splenic nodules were observed.Infection or hemangioma was considered;however,no specific radiological findings were observed.A biopsy of the spleen was performed to determine the possibility of malignancy.The histological findings of the spleen included extensive periarteriolar necrosis with hematoxylin bodies and numerous karyorrhectic debris.Based on the biopsy results,the patient was diagnosed with an SLE flare-up and was maintained on high-dose steroids and immunosuppressants.CONCLUSION As disease activity increased,multiple nodules in the spleen that were previously unseen were observed using AP-CT and histologically confirmed.Spleen invasion by SLE can appear in multiple nodular forms and patterns.Therefore,physicians should consider these findings when differentiating these nodules from infections and malignancies. 展开更多
关键词 Multiple nodules Spleen SPLENECTOMY systemic lupus erythematosus Differential diagnosis Case report
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Neurogenic potential of NG2 in neurotrauma:a systematic review
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作者 Yuri R.Rigo Radharani Benvenutti +1 位作者 Luis V.Portela Nathan R.Strogulski 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2673-2683,共11页
Regenerative approaches towards neuronal loss following traumatic brain or spinal cord injury have long been considered a dogma in neuroscience and remain a cutting-edge area of research.This is reflected in a large d... Regenerative approaches towards neuronal loss following traumatic brain or spinal cord injury have long been considered a dogma in neuroscience and remain a cutting-edge area of research.This is reflected in a large disparity between the number of studies investigating primary and secondary injury as therapeutic to rgets in spinal co rd and traumatic brain injuries.Significant advances in biotechnology may have the potential to reshape the current state-of-the-art and bring focus to primary injury neurotrauma research.Recent studies using neural-glial factor/antigen 2(NG2)cells indicate that they may differentiate into neurons even in the developed brain.As these cells show great potential to play a regenerative role,studies have been conducted to test various manipulations in neurotrauma models aimed at eliciting a neurogenic response from them.In the present study,we systematically reviewed the experimental protocols and findings described in the scientific literature,which were peer-reviewed original research articles(1)describing preclinical experimental studies,(2)investigating NG2 cells,(3)associated with neurogenesis and neurotrauma,and(4)in vitro and/or in vivo,available in PubMed/MEDLINE,Web of Science or SCOPUS,from 1998 to 2022.Here,we have reviewed a total of 1504 papers,and summarized findings that ultimately suggest that NG2 cells possess an inducible neurogenic potential in animal models and in vitro.We also discriminate findings of NG2 neurogenesis promoted by different pharmacological and genetic approaches over functional and biochemical outcomes of traumatic brain injury and spinal co rd injury models,and provide mounting evidence for the potential benefits of manipulated NG2 cell ex vivo transplantation in primary injury treatment.These findings indicate the feasibility of NG2 cell neurogenesis strategies and add new players in the development of therapeutic alternatives for neurotrauma. 展开更多
关键词 neural-glial antigen 2 neural-glial factor 2 neuron differentiation NG2 cell regeneration spinal cord injury(SCI) traumatic brain injury(TBI)
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Novel Adaptive Memory Event-Triggered-Based Fuzzy Robust Control for Nonlinear Networked Systems via the Differential Evolution Algorithm
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作者 Wei Qian Yanmin Wu Bo Shen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1836-1848,共13页
This article mainly investigates the fuzzy optimization robust control issue for nonlinear networked systems characterized by the interval type-2(IT2)fuzzy technique under a differential evolution algorithm.To provide... This article mainly investigates the fuzzy optimization robust control issue for nonlinear networked systems characterized by the interval type-2(IT2)fuzzy technique under a differential evolution algorithm.To provide a more reasonable utilization of the constrained communication channel,a novel adaptive memory event-triggered(AMET)mechanism is developed,where two event-triggered thresholds can be dynamically adjusted in the light of the current system information and the transmitted historical data.Sufficient conditions with less conservative design of the fuzzy imperfect premise matching(IPM)controller are presented by introducing the Wirtinger-based integral inequality,the information of membership functions(MFs)and slack matrices.Subsequently,under the IPM policy,a new MFs intelligent optimization technique that takes advantage of the differential evolution algorithm is first provided for IT2 TakagiSugeno(T-S)fuzzy systems to update the fuzzy controller MFs in real-time and achieve a better system control effect.Finally,simulation results demonstrate that the proposed control scheme can obtain better system performance in the case of using fewer communication resources. 展开更多
关键词 Adaptive memory event-triggered(AMET) differential evolution algorithm fuzzy optimization robust control interval type-2(IT2)fuzzy technique.
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Bruton’s tyrosine kinase inhibitors in primary central nervous system lymphoma:New hopes on the horizon
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作者 Leonardo S Lino-Silva Sabrina B Martínez-Villavicencio Luisa Fernanda Rivera-Moncada 《World Journal of Clinical Oncology》 2024年第5期587-590,共4页
In this editorial,we comment on the article by Wang et al.This manuscript explores the potential synergistic effects of combining zanubrutinib,a novel oral inhibitor of Bruton’s tyrosine kinase,with high-dose methotr... In this editorial,we comment on the article by Wang et al.This manuscript explores the potential synergistic effects of combining zanubrutinib,a novel oral inhibitor of Bruton’s tyrosine kinase,with high-dose methotrexate(HD-MTX)as a therapeutic intervention for primary central nervous system lymphoma(PCNSL).The study involves a retrospective analysis of 19 PCNSL patients,highlighting clinicopathological characteristics,treatment outcomes,and genomic biomarkers.The results indicate the combination’s good tolerance and strong antitumor activity,with an 84.2%overall response rate.The authors emphasize the potential of zanubrutinib to modulate key genomic features of PCNSL,particularly mutations in myeloid differentiation primary response 88 and cluster of differentiation 79B.Furthermore,the study investigates the role of circulating tumor DNA in cerebrospinal fluid for disease surveillance and treatment response monitoring.In essence,the study provides valuable insights into the potential of combining zanubrutinib with HD-MTX as a frontline therapeutic regimen for PCNSL.The findings underscore the importance of exploring alternative treatment modalities and monitoring genomic and liquid biopsy markers to optimize patient outcomes.While the findings suggest promise,the study’s limitations should be considered,and further research is needed to establish the clinical relevance of this therapeutic approach for PCNSL. 展开更多
关键词 Primary central nervous system lymphoma Zanubrutinib Bruton’s tyrosine kinase PROGNOSIS Myeloid differentiation primary response 88 gene Cluster of differentiation 79B gene
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Design and Analysis of Power and Transmission System of Downhole Pure Electric Command Vehicle
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作者 Md Jahangir Alam Md Shahriar Sujan +1 位作者 Md. Al Imran Tapu Joy Howlader 《Journal of Transportation Technologies》 2024年第1期31-52,共22页
Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technol... Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technology with ideal power and torque curves for vehicular operation. Conventional vehicles use oil and gas as fuel or energy storage. Although they also have an excellent economic impact, the continuous use of oil and gas threatened the world’s reservation of total oil and gas. Also, they emit carbon dioxide and some toxic ingredients through the vehicle’s tailpipe, which causes the greenhouse effect and seriously impacts the environment. So, as an alternative, electric car refers to a green technology of decarbonization with zero emission of greenhouse gases through the tailpipe. So, they can remove the problem of greenhouse gas emissions and solve the world’s remaining non-renewable energy storage problem. Pure electric vehicles (PEV) can be applied in all spheres, but their special implementation can only be seen in downhole operations. They are used for low noise and less pollution in the downhole process. In this study, the basic structure of the pure electric command vehicle is studied, the main components of the command vehicle power system, namely the selection of the drive motor and the power battery, are analyzed, and the main parameters of the drive motor and the power battery are designed and calculated. The checking calculation results show that the power and transmission system developed in this paper meets the design requirements, and the design scheme is feasible and reasonable. 展开更多
关键词 Pure Electric Vehicles TRANSMISSION GEARS Electronic Differential Control Algorithms
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The Jaffa Transform for Hessian Matrix Systems and the Laplace Equation
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作者 Daniel A. Jaffa 《Journal of Applied Mathematics and Physics》 2024年第1期98-125,共28页
Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of ... Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of linear second-order partial differential equations. This paper discusses the Hessian and its applications in optimization, and then proceeds to introduce and derive the notion of the Jaffa Transform, a new linear operator that directly maps a Hessian square matrix space to the initial corresponding scalar field in nth dimensional Euclidean space. The Jaffa Transform is examined, including the properties of the operator, the transform of notable matrices, and the existence of an inverse Jaffa Transform, which is, by definition, the Hessian matrix operator. The Laplace equation is then noted and investigated, particularly, the relation of the Laplace equation to Poisson’s equation, and the theoretical applications and correlations of harmonic functions to Hessian matrices. The paper concludes by introducing and explicating the Jaffa Theorem, a principle that declares the existence of harmonic Jaffa Transforms, which are, essentially, Jaffa Transform solutions to the Laplace partial differential equation. 展开更多
关键词 Hessian Matrices Jacobian Matrices Laplace Equation Linear Partial Differential Equations systems of Partial Differential Equations Harmonic Functions Incompressible and Irrotational Fluid Mechanics
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Multiple Solutions for a Class of Singular Boundary Value Problems of Hadamard Fractional Differential Systems with p-Laplacian Operator
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作者 Chen Wang Yansheng Liu 《Journal of Applied Mathematics and Physics》 2024年第9期3114-3134,共21页
This paper discusses the existence and multiplicity of positive solutions for a class of singular boundary value problems of Hadamard fractional differential systems involving the p-Laplacian operator. First, for the ... This paper discusses the existence and multiplicity of positive solutions for a class of singular boundary value problems of Hadamard fractional differential systems involving the p-Laplacian operator. First, for the sake of overcoming the singularity, sequences of approximate solutions to the boundary value problem are obtained by applying the fixed point index theory on the cone. Next, it is demonstrated that these sequences of approximate solutions are uniformly bounded and equicontinuous. The main results are then established through the Ascoli-Arzelà theorem. Ultimately, an instance is worked out to test and verify the validity of the main results. 展开更多
关键词 Multiple Solutions Fixed Point Index Theory Nonlinear Fractional Differential systems Hadamard Fractional Derivative
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Legendre-Weighted Residual Methods for System of Fractional Order Differential Equations
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作者 Umme Ruman Md. Shafiqul Islam 《Journal of Applied Mathematics and Physics》 2024年第9期3163-3184,共22页
The numerical approach for finding the solution of fractional order systems of boundary value problems (BPVs) is derived in this paper. The implementation of the weighted residuals such as Galerkin, Least Square, and ... The numerical approach for finding the solution of fractional order systems of boundary value problems (BPVs) is derived in this paper. The implementation of the weighted residuals such as Galerkin, Least Square, and Collocation methods are included for solving fractional order differential equations, which is broadened to acquire the approximate solutions of fractional order systems with differentiable polynomials, namely Legendre polynomials, as basis functions. The algorithm of the residual formulations of matrix form can be coded efficiently. The interpretation of Caputo fractional derivatives is employed here. We have demonstrated these methods numerically through a few examples of linear and nonlinear BVPs. The results in absolute errors show that the present method efficiently finds the numerical solutions of fractional order systems of differential equations. 展开更多
关键词 Fractional Differential Equations system of Fractional Order BVPs Weighted Residual Methods Modified Legendre Polynomials
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Study on Sex Ratio of Lampreys Based on Simulated Ecosystem-Food Web Model
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作者 Ziyuan Zhao Xinqi Hao Jinyang Xia 《Journal of Applied Mathematics and Physics》 2024年第8期2959-2989,共31页
Lampreys, as an important participant in the ecosystem, play an irreplaceable role in the stability of nature. A variety of models were used to simulate ecosystems and food webs, and the dynamic evolution of multiple ... Lampreys, as an important participant in the ecosystem, play an irreplaceable role in the stability of nature. A variety of models were used to simulate ecosystems and food webs, and the dynamic evolution of multiple populations was solved. The temporal changes of the biomass and the health of the ecosystem affected by the population of Lampreys in other ecological niches were solved. For problem 1, Firstly, a simple natural ecosystem is simulated based on the threshold model and BP neural network model. The dynamic change of the sex ratio of lampreys population and the fluctuation of ecosystem health value were found to generate time series maps. Lampreys overprey on low-niche animals, which damages the overall stability of the ecosystem. For problem 2, We used the Lotka-Volterra model to construct ecological competition between lampreys and primary consumers and predators. Then, the Lotka-Volterra equations were solved, and a control group without gender shift function was set up, which reflected the advantages and disadvantages of the sex-regulated characteristics of lampreys in the natural environment. For problem 3, The ecosystem model established in question 1 was further deepened, and the food web was simulated by the Beverton-Holt model and the Logistic time-dependent differential equations model. The parameters of the food web model were input into the neurons of the ecosystem model, and the two models were integrated to form an overall biosphere model. The output layer of the ecosystem neural network was input into the food web Beverton-Holt and Logistic differential equations, and finally, the three-dimensional analytical solution was obtained by numerical simulation. Then Euler method is used to obtain the exact value of the solution surface. The Random forest model was used to predict the future development of lampreys and other ecological niches. For problem 4, By investigating relevant literature, we normalized the populations of lampreys and a variety of fish as well as other ecological niche animals, plants and microorganisms in the same water area, set different impact weights of lampreys, constructed weight evaluation matrix, and obtained positive and negative ideal solution vectors and negative correlation proximity by using TOPSIS comprehensive evaluation method. It is concluded that many kinds of fish are greatly affected by the sex regulation of lampreys. 展开更多
关键词 BP Neural Network Model LAMPREY Beverton-Holt and Logistic Differential Equations systems TOPSIS Comprehensive Evaluation Method
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The Solvability of the Degenerate Differential Systems with Delay 被引量:5
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作者 蒋威 郑祖庥 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期1-7,共7页
In this paper we study the degenerate differential system with delay:E(t)=Ax(t)+Bx(t-1)+f(t),give the canonical form of this systems and study this form of degeneration system with delay,have some results for the so... In this paper we study the degenerate differential system with delay:E(t)=Ax(t)+Bx(t-1)+f(t),give the canonical form of this systems and study this form of degeneration system with delay,have some results for the solvability of such systems and the uniqueness of their solutions. 展开更多
关键词 degenerate differential system with delay regular system SOLVABILITY
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Research Progress of Differential Systems for Physiological Races of Plasmodiophora brassicae Wor 被引量:1
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作者 刘勇 罗一帆 +2 位作者 黄小琴 张蕾 刘红雨 《Agricultural Science & Technology》 CAS 2012年第10期2236-2241,2256,共7页
Research progress was reviewed on the differential systems for physiologic races of Plasmodiophora brassicae Woron,including Williams,differential system and European clubroot differential(ECD) set.The existing prob... Research progress was reviewed on the differential systems for physiologic races of Plasmodiophora brassicae Woron,including Williams,differential system and European clubroot differential(ECD) set.The existing problems and countermeasures of the different differential systems were discussed,and a research status quo on the molecular identification and detection of clubroot pathogen in crucifers were introduced. 展开更多
关键词 Plasmodiophora brassicae Woron Physiological races Williams' differential system ECD(European Clubroot Differential) set
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Comparative Study on Genetic Diversity of Beauveria bassiana in Different Forest Ecosystems 被引量:1
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作者 陈名君 刘玉军 +1 位作者 李增智 黄勃 《Plant Diseases and Pests》 CAS 2010年第6期68-72,共5页
ISSR molecular marker technology was adopted to conduct comparison analysis on genetic diversity level and population genetic structure of Beauveria bassiana population in natural secondary forest (Langyashan nationa... ISSR molecular marker technology was adopted to conduct comparison analysis on genetic diversity level and population genetic structure of Beauveria bassiana population in natural secondary forest (Langyashan national forest park) in Chuzhou City of Anhui Province and artificial pure pine forest (Magushan forest farm) in Xuancheng City of Anhui Province.Seven primers were selected to conduct PCR amplification on total 222 strains of B.bassiana in two populations,a total of 58 unique amplified loci were obtained through amplification,the number of polymorphic loci was 56,the percentage of polymorphic loci was 96.55%,Nei's genetic diversity was 0.299 3,Shannon information index was 0.459 3,genetic differentiation coefficient among populations (Gst) was 0.128 3,gene flow Nm=3.398 4;the gene flow between the two populations was small,genetic differentiation was relatively large,being 12.83%,this may be caused by human selective pressures and barrier of gene flow;the genetic variation level of B.bassiana populations in Langyashan was relatively high(PPL=96.55%,H=0.278 1,I= 0.429 9);the genetic variation level of B.bassiana populations in Magushan was relatively low(PPL=93.10%,H=0.255 2,I= 0.382 5).The genetic diversity of B.bassiana from the primary forest in Dabieshan was studied(PPL=81.00%,H=0.318 7,I= 0.478 2),indicating that the genetic diversity of B.bassiana populations in Dabieshan with complex ecological environment was the highest,followed by the populations in natural secondary forest,and the genetic diversity in artificial pure pine forest was the lowest.Nei's genetic distance was adopted to construct the genetic relationship dendrogram of B.bassiana individuals collected from Langyashan and Magushan,from the cluster analysis of UPGMA,the strains from the same collection places clustered together. 展开更多
关键词 Entomopathogenic fungi Molecular marker Gene flow Genetic differentiation Genetic diversity
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Oscillation of Systems of Parabolic Differential Equations with Deviating Arguments 被引量:1
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作者 邓立虎 王宏洲 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期12-16,共5页
To study a class of boundary value problems of parabolic differential equations with deviating arguments, averaging technique, Green’s formula and symbol function sign(·) are used. The multi dimensional problem... To study a class of boundary value problems of parabolic differential equations with deviating arguments, averaging technique, Green’s formula and symbol function sign(·) are used. The multi dimensional problem was reduced to a one dimensional oscillation problem for ordinary differential equations or inequalities. Two oscillatory criteria of solutions for systems of parabolic differential equations with deviating arguments are obtained. 展开更多
关键词 systems of parabolic differential equations boundary value problem deviating arguments OSCILLATION
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