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Communications in Theoretical Physics 2017年第2期67卷 222-230页

作者： S.Kotambkar G.P.Singh r.kelkar Binaya K.Bishi Department of Applied Mathematics LIT RTM Nagpur University Nagpur India Department of Mathematics VNIT Nagpur India Department of Applied Mathematics SB Jain ITMR Nagpur India

This paper deals with study of generalized Chaplygin gas model with dynamical gravitational and cosmological constants. In this paper a new set of exact solutions of Einstein field equations for spatially homogeneous and anisotropic Bianchi type Ⅰ space-time have been obtained. The solutions of the Einstein's field equations are obtained by considering(i) the power law relation between Hubble parameter H and scale factor r and(ii) scale factor of the form r =-1/t + t^2, t > 1. The assumptions lead to constant and variable deceleration parameter respectively. The physical and dynamical behaviors of the models have been discussed with the help of graphical representations. Also we have discussed the stability and physical acceptability of solutions for solution type-Ⅰ and solution type-Ⅱ.

关键词： Bianchi type Ⅰ space tine cosmological constant gravitational constant generalized Chaplygin gas

New dynamic permeability upscaling method for flow simulation under depletion drive and no-crossflow conditions

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Petroleum Science 2013年第2期10卷 233-241页

作者： Mohammad Sharifi Mohan kelkar McDougall School of Petroleum Engineering The University of Tulsa800 South Tucker DriveTulsaOklahoma74104United States

The main purpose of upscaling in reservoir simulation is to capture the dynamic behavior of fine scale models at the coarse scale. Traditional static or dynamic methods use assumptions about the boundary conditions to determine the upscaled properties, in this paper, we show that the upscaled properties are strongly dependent on the flow process observed at the fine scale. We use a simple no- crossflow depletion drive process and demonstrate that an upscaled property is not a constant value. Instead, if the goal is to match the performance of the fine scale model, the upscaled permeability changes with time. We provide an analytical solution to determine the upscaled permeability and present the value of upscaled permeability under limiting conditions. Our equation suggests that it is possible that upscaled value can fall outside the range of fine scale values under certain conditions. We show that for pseudo steady state flow, using common averaging methods like arithmetic or even geometric averaging methods can lead to optimistic results. We also show that the no-crossflow solution is significantly different than crossflow solution at late times. We validate our method by comparing the results of the method with flow simulation results in two and multi-layered models.

关键词： Upscaling permeability reservoir simulation no-crossflow depletion drive

Machine Learning Techniques in Predicting Hot Deformation Behavior of Metallic Materials

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek Department of Metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.

关键词： Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

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Neural regeneration research 2025年第9期20卷 2591-2593页

作者： Alena Salasova Anders Nykjær Danish research Institute of Translational Neuroscience DANDrITE-Nordic EMBL Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2

A comprehensive investigation on nonlinear vibration and bending characteristics of bio-inspired helicoidal laminated composite structures

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAUrABH r.KIrAN D.SINGH r.VAISH V.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

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Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural regeneration research 2025年第3期20卷 803-804页

作者： Glenn A.Harris Lauren r.Hirschfeld rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3r) or 4-repeat(4r) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases

Variability in physical properties of plantation-grown progenies of Melia composita and determination of a kiln-drying schedule

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Journal of Forestry research 2018年第5期29卷 1435-1442页

作者： Shailendra Kumar Bhushan U.kelkar Ajit K.Mishra Susanta K.Jena Forest Products Division Forest Research Institute

Plantation-grown progenies of Melia composita *** studied for variability in several physical properties： density,radial and tangential shrinkage,longitudinal permeability of heartwood and ***,flat-sawn planks from each of the progeny were subjected to a quick-drying test for determination of kilndrying *** mean density of the species was 0.39 g cm^（-3） and the wood may be categorized as light *** radial shrinkage（%） for the species was 2.8% with progeny-wise variation in radial shrinkage from 1.56 to 4.11%.Mean tangential shrinkage（%） for the species was 5.54% with progeny-wise variation in tangential shrinkage from 3.69 to 7.71%.The resultant tangentialradial shrinkage ratio was 1.98（less than two）,which suggests that the wood is relatively stable with respect to drying *** sapwood and heartwood longitudinal permeability of the species were 3.38 and 2.02 Darcy,*** longitudinal permeability of sapwood and heartwood indicate better drying and preservative properties of the *** quick-drying test method suggests that the species is less susceptible to drying *** the test,only moderate checks and cracks were observed.A tentative kiln-drying schedule was recommended based on these results.

关键词： Melia composita Willd. Density radial and tangential shrinkage Longitudinal permeability Quickdrying test Kiln-drying schedule

Oxidation of propane to acrylic acid and acetic acid over alkaline earth-doped Mo-V-Sb-O_x catalysts

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Journal of Natural Gas Chemistry 2010年第6期19卷 593-599页

作者： Chandan S.Chaudhari Shailesh S.Sable Hanumant Gurav Ashutosh A.kelkar Vilas H.rane Chemical Engineering and Process Development Division National Chemical Laboratory Catalysis Division National Chemical Laboratory

Alkaline earth metal （Mg,Ca,Sr and Ba）-doped Mo-V-Sb-O x catalysts,prepared by a dry-up method,have been investigated for their catalytic performance in the oxidation of propane under different reaction *** catalysts have been characterized by N2 adsorption-desorption,temperature-programmed desorption （TPD） of NH3,SEM and *** of water vapor on the catalytic performance,particularly on the selectivities to acetic acid and acrylic acid,has also been *** selectivity to acrylic acid was improved significantly by the doping of alkaline earth metals to Mo-V-Sb-O x *** surface acidic sites of the catalyst decreased with the doping of the catalyst with alkaline earth metals,which ultimately was found to be beneficial for obtaining high selectivity to acrylic *** catalytic activity and product selectivities were found to be influenced by the reaction temperature,C3H8/O2 ratio and space velocity.A significant improvement in the selectivity to acrylic acid has also been observed by the addition of water vapor in the feed of propane and oxygen in the oxidation of propane.

关键词： oxidation of propane surface acidity alkaline earth doped Mo-V-Sb-Ox catalysts acrylic acid acetic acid

Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural regeneration research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam M.r.Groh Moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.r.Wayne Moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by robertson and río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus rNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets

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Neural regeneration research 2025年第3期20卷 725-739页

作者： Benjamin r.Helmold Angela Ahrens Zachary Fitzgerald P.Hande Ozdinler Department of Neurology Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Center for Molecular Innovation and Drug Discovery Center for Developmental TherapeuticsChemistry of Life Processes InstituteNorthwestern UniversityEvanstonILUSA Mesulam Center for Cognitive Neurology and Alzheimer’s Disease Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Feinberg School of Medicine Les Turner ALS Center at Northwestern UniversityChicagoILUSA

Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. Protein–protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as “causative” for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration–approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous.

关键词： ALS2 alsin amyotrophic lateral sclerosis hereditary spastic paraplegia neurodegenerative diseases personalized medicine precision medicine protein interactome protein-protein interactions SPAST spastin