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A novel method for clustering cellular data to improve classification

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Neural Regeneration Research 2025年第9期20卷 2697-2705页

作者： Diek w.wheeler Giorgio A.Ascoli Center for Neural Informatics Structures&PlasticityKrasnow Institute for Advanced Study Bioengineering Department Volgenau School of Engineering George Mason University FairfaxVAUSA

Many fields,such as neuroscience,are experiencing the vast prolife ration of cellular data,underscoring the need fo r organizing and interpreting large datasets.A popular approach partitions data into manageable subsets via hierarchical clustering,but objective methods to determine the appropriate classification granularity are *** recently introduced a technique to systematically identify when to stop subdividing clusters based on the fundamental principle that cells must differ more between than within *** we present the corresponding protocol to classify cellular datasets by combining datadriven unsupervised hierarchical clustering with statistical *** general-purpose functions are applicable to any cellular dataset that can be organized as two-dimensional matrices of numerical values,including molecula r,physiological,and anatomical *** demonstrate the protocol using cellular data from the Janelia MouseLight project to chara cterize morphological aspects of neurons.

关键词： cellular data clustering dendrogram data classification Levene's one-tailed statistical test unsupervised hierarchical clustering

Genistein:a possible solution for the treatment of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2903-2905页

作者： Karolina Pierzynowska Bartosz Karaszewski Grzegorz węgrzyn Department of Molecular Biology University of GdanskGdanskPoland Gdansk Polandand Department of Adult NeurologyFaculty of MedicineMedical University of GdanskGdanskPoland

Neurodegenerative diseases are defined as disorders resulting from the slow and progressive loss of function and eventual death of neural cells that result from the primary pathology of nervous *** can lead to severe nervous system dysfunction,eventually affecting multiple organs and *** hundred neurodegenerative diseases have been described,and owing to their prevalence,severity.

关键词： organs Alzheimer death

Glia-to-neuron reprogramming to the rescue?

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Neural Regeneration Research 2025年第5期20卷 1395-1396页

作者： Jack w.Hickmott Cindi M.Morshead Department of Surgery University of TorontoTorontoONCanada Donnelly Centre for Cellular and Biomolecular Research TorontoONCanada Institute of Biomedical Engineering University of TorontoTorontoONCanada The KITE Research Institute Toronto Rehabilitation InstituteUniversity Health NetworkTorontoONCanada

Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative *** brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be *** exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.

关键词： programming passing proof

Modeling and Simulation of Microstructurally Small Crack Formation and Growth in Notched Nickel-base Superalloy Component

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Journal of Materials Science & Technology 2014年第3期30卷 203-212页

作者： G.M.Owolabi H.A.whitworth Department of Mechanical Engineering Howard University

Studies on microstructurally small fatigue cracks have illustrated that heterogeneous microstructural features such as inclusions, pores, grain size distribution as well as precipitate size distribution and volume fraction create stochasticity in their behavior under cyclic loads. Therefore, to enhance safe-life and damage-tolerance approaches, accurate modeling of the influence of these heterogeneous microstructural features on microstructurally small crack formation and growth from stress raisers is necessary. In this work, computational micromechanics was used to predict the high cycle fatigue of microstructurally small crack formation and growth in notched polycrystalline nickel-base superalloys and to quantify the variability in the driving force for formation and growth of microstructurally small crack from notch root in the matrix with non-metallic inclusions. The framework involves computational modeling to obtain three-dimensional perspectives of microstructural features influencing fatigue crack growth in notched nickel-base superalloys, which accounts for the effects of nonlocal notch root plasticity, loading, microstructural variability, and extrinsic defects on local cyclic plasticity at the microstructure-scale level. This approach can be used to explore sensitivity of minimum fatigue lifetime to microstructures. The simulation results obtained from this framework were calibrated to existing experimental results for polycrystalline nickel-base superalloys.

关键词： Microstructuraliy small crack Crystal plasticity Nickel-base superalloy Fatigue life

Shear Band Formation in AISI 4340 Steel Under Dynamic Impact Loads:Modeling and Experiment

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 378-384页

作者： Daniel Odoh Gbadebo Owolabi Akindele Odeshi Horace whitworth Department of Mechanical Engineering Howard University Department of Mechanical Engineering University of Saskatchewan57 Campus DriveSaskatoonSKS7N 5A9Canada

In this study, the occurrence of the adiabatic shear bands in AISI 4340 steel under high velocity impact loading was investigated using finite element analysis and experimental tests. The cylindrical specimen subjected to the impact load was divided into different regions separated by nodes using finite element method in ABAQUS environment with boundary conditions specified. The material properties were assumed to be lower in the region where the probability of strain localization is high based on prior experimental results in order to initialize the formation of the adiabatic shear bands. The finite element model was used to determine the maximum flow stress, the strain hardening, the thermal softening, and the time to reach the critical strain for the formation of adiabatic shear bands. Experimental results show that deformed bands were formed at low strain rates and there was a minimum strain rate required for the formation of the transformed band in the alloy and the cracks were initiated and propagated along the transformed bands leading to fragmentation under the impact loading. The susceptibility of the adiabatic shear bands to cracking was markedly influenced by the strain-rates and the initial material microstructure. The simulation results obtained were compared with the experimental results obtained from the AISI 4340 steel under high strain-rate loading in compression using split impact Hopkinson bars. A good agreement between the experimental and simulation results was obtained.

关键词： Adiabatic shear bands Finite element model Strain hardening Thermal softening Johnson-Cook model AISI 4340 steel

Apolipoprotein A1,the neglected relative of Apolipoprotein E and its potential role in Alzheimer’s disease

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Neural Regeneration Research 2021年第11期16卷 2141-2148页

作者： kristina Endres Department of Psychiatry and Psychotherapy University Medical Center of the Johannes Gutenberg-University MainzUntere Zahlbacher Str.855131 MainzGermany

Lipoproteins are multi-molecule assemblies with the primary function of transportation and processing of lipophilic substances within aqueous bodily fluids(blood,cerebrospinal fluid).Nevertheless,they also exert other physiological functions such as immune *** particular,neurons are both sensitive to uncontrolled responses of the immune system and highly dependent on a controlled and sufficient supply of *** this reason,the role of certain lipoproteins and their protein-component(apolipoproteins,Apo’s)in neurological diseases is ***,for example,is well-accepted as one of the major risk factors for sporadic Alzheimer’s disease with a protective allele variant(ε2)and a risk-causing allele variant(ε4).ApoA1,the major protein component of high-density lipoproteins,is responsible for transportation of excess cholesterol from peripheral tissues to the *** protein is synthesized in the liver and intestine but also can enter the brain via the choroid plexus and thereby might have an impact on brain lipid *** review focuses on the role of ApoA1 in Alzheimer’s disease and discusses whether its role within this neurodegenerative disorder is specific or represents a general neuroprotective mechanism.

关键词： Aβ ApoA1 cholesterol high-density lipoproteins lipids lipoprotein neurodegeneration senile plaque

The Application of Model-Based Systems Engineering to Rural Healthcare System Disaster Planning:A Scoping Review

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International Journal of Disaster Risk Science 2023年第3期14卷 357-368页

作者： Thomas A.Berg Kelsi N.Marino kristina w.Kintziger College of Nursing University of Tennessee-KnoxvilleKnoxvilleTN37966USA College of Public Health University of Nebraska Medical CenterOmahaNE68198USA

Disasters and other emergency events have complex effects on human systems,particularly if the events are severe or *** these types of events happen in rural communities,the resources of the local public health,healthcare,and emergency response organizations can be quickly depleted or *** for emergencies can help to mitigate their ***-based systems engineering(MBSE)methods,including computer simulations,can provide insight on how best to prepare for these events and to explore the effects of varying approaches and resource *** best apply these methods for improving disaster management in rural settings,a synthesis of the current body of evidence in this field is *** objective of this scoping review was to provide a descriptive overview of the application of computer simulation based on MBSE approaches to disaster preparedness and response for rural healthcare *** studies met inclusion criteria,and varied in terms of MBSE method used,healthcare setting,and disaster type and context *** identified a gap in the research regarding the application of MBSE approaches to support rural healthcare disaster preparedness planning ***-based systems engineering and systems thinking,therefore,represent novel methods for developing tools and computational simulations that could assist rural communities better prepare for disasters.

关键词： Computer simulation Disaster preparedness Model-based systems engineering Rural healthcare Systems thinking

Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU w.M.HUANG College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of Mechanical and Aerospace Engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

关键词： Constitutive equations

Human induced pluripotent stem cell-derived therapies for regeneration after central nervous system injury

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Neural Regeneration Research 2025年第11期20卷 3063-3075页

作者： Stephen Vidman Yee Hang Ethan Ma Nolan Fullenkamp Giles w.Plant Department of Neuroscience Ohio State UniversityColumbusOHUSA

In recent years,the progression of stem cell therapies has shown great promise in advancing the nascent field of regenerative *** the non-regenerative nature of the mature central nervous system,the concept that“blank”cells could be reprogrammed and functionally integrated into host neural networks remained *** work has also demonstrated the ability of such cells to stimulate intrinsic growth programs in post-mitotic cells,such as *** embryonic stem cells demonstrated great potential in treating central nervous system pathologies,ethical and technical concerns *** barriers,along with the clear necessity for this type of treatment,ultimately prompted the advent of induced pluripotent stem *** advantage of pluripotent cells in central nervous system regeneration is multifaceted,permitting differentiation into neural stem cells,neural progenitor cells,glia,and various neuronal *** precise spatiotemporal application of extrinsic growth factors in vitro,in addition to microenvironmental signaling in vivo,influences the efficiency of this directed *** the pluri-or multipotency of these cells is appealing,it also poses the risk of unregulated differentiation and teratoma *** of the neuroectodermal lineage,such as neuronal subpopulations and glia,have been explored with varying degrees of *** the risk of cancer or teratoma formation is greatly reduced,each subpopulation varies in effectiveness and is influenced by a myriad of factors,such as the timing of the transplant,pathology type,and the ratio of accompanying progenitor ***,successful transplantation requires innovative approaches to develop delivery vectors that can mitigate cell death and support ***,host immune responses to allogeneic grafts must be thoroughly characterized and further developed to reduce the need for *** to a clinical setting wi

关键词： axon regeneration central nervous system regeneration induced pluripotent stem cells neurotrauma regenerative medicine spinal cord injury stem cell therapy