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中国有色金属学会会刊：英文版 2010年第S3期20卷 774-780页

作者： P.GERALD TENNYSON P.KUMAR h.lakshmi G.PhANIKUMAR P.DUTTA Department of Metallurgical and Materials Engineering Indian Institute of Technology National Facility for Semisolid Forming Department of Mechanical EngineeringIndian Institute of Science

Thixocasting requires manufacturing of billets with non-dendritic *** alloy A356 billets were produced by rheocasting in a mould placed inside a linear electromagnetic *** heat treatment was used to produce a transition from rosette to globular *** current and the duration of stirring were explored as control *** induction heating of the billet during stirring was quantified using experimentally determined thermal *** effect of processing parameters on the dendrite fragmentation was *** computational modeling of the process was performed using phase-field modeling of alloy solidification in order to gain insight into the process of morphological changes of a solid during this process.A non-isothermal alloy solidification model was used for *** morphological evolution under such imposed thermal cycles was simulated and compared with experimentally determined *** scaling using the thermosolutal diffusion distances was used to overcome computational difficulties in quantitative comparison at system *** results were interpreted in the light of existing theories of microstructure refinement and globularisation.

关键词： electromagnetic stirring non-dendritic phase field modeling microstructure

Induction reheating of A356.2 aluminum alloy and thixocasting as automobile component

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中国有色金属学会会刊：英文版 2010年第S3期20卷 961-967页

作者： h.lakshmi M.C.VINAY KUMAR RAGhUNATh P.KUMAR V.RAMANARAYANAN K.S.S.MURThY P.DUTTA National Facility for Semisolid Forming Department of Mechanical EngineeringIndian Institute of Science Department of Electrical Engineering Indian Institute of Science

The development work for producing an automobile component by thixocasting using A356.2 alloy was *** the first step,the alloy was electromagnetically stirred and solidified to produce a billet with non-dendritic *** microstructure depended on several process parameters such as stirring intensity,stirring frequency,cooling rate,and melt initial *** a series of computational studies and controlled experiments,a set of process parameters were identified to produce the best *** of a billet with non-dendritic microstructure to a semisolid temperature was the next step for thixo-casting of the *** reheating process was characterized for various reheating cycles using a vertical-type reheating *** induction heating cycle was optimized to obtain a near-uniform temperature distribution in radial as well as axial direction of the billet,and the heating was continued until the liquid fraction reached about 50%.These parameters were determined with the help of a computational fluid dynamics(CFD) model of die filling and solidification of the semisolid *** heated billets were subsequently thixo-cast into automobile components using a real-time controlled die casting *** results show that the castings are near net shape,free from porosity,good surface finish and have superior mechanical properties compared to those produced by conventional die casting processes using the same alloy.

关键词： aluminum alloy thixo-casting electromagnetic stirring induction reheating process parameters

Semantic Segmentation of Lumbar Vertebrae Using Meijering U-Net(MU-Net)on Spine Magnetic Resonance Images

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 733-757页

作者： lakshmi S V V Shiloah Elizabeth Darmanayagam Sunil Retmin Raj Cyril Department of Computer Science and Engineering College of Engineering GuindyAnna UniversityChennai600025India Department of Information Technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic Resonance Imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic Resonance Images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from T1-weighted mid-sagittal MRI images of 515 patients in the Lumbar Spine MRI Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean Intersection over Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar vertebrae deep learning U-Net model

Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Comparative chemical sensor for detection of chromium(Ⅵ) in aqueous solution

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Optoelectronics Letters 2025年第1期21卷 21-27页

作者： Sura h.AL-REKABI A.A.ALWAhIB Electrical Technique Department Al Suwayrah Technical Institute Middle Technical University Laser and Optoelectronics Department University of Technology-Iraq

A process for purifying aqueous solutions containing heavy and toxic metals such as chromium（Cr） has been investigated. One of the extremely harmful pollutants in rivers and seawater is the heavy metal ions due to their direct impacts on human, animals and plants are hexavalent Cr（Ⅵ）. Consequently, highly sensitive sensor to detect Cr is essential. Surface plasmon resonance（SPR） technique has attracted huge research interest in detecting heavy metals specifically. In this study, three types of prism-based SPR sensor, gold（Au）/silver（Ag）, Au/polyaniline（PANI） and Au/titanium dioxide（TiO2） nanostructured films, are investigated as potential sensing material to detect the presence of Cr（Ⅵ） ions in water. The base Au layer with thickness of 48.3 nm is deposited on a glass slide for all sensors. For Au/Ag, Au/PANI nanofibers and Au/TiO2sensor films, the Cr（Ⅵ） concentration is varied from 1 ppm to 15 ppm with sensitivity of 0.270 °ppm-1, 0.082 °ppm-1and 0.039 °ppm-1, respectively. Based on these results, the Au/PANI nanofibers are the most sensitive to Cr（Ⅵ） among the tested sensing materials.

关键词： Titanium dioxide

Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri h.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

Renewable energy resources, policies and gaps in BRICS countries and the global impact

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Frontiers in Energy 2019年第3期13卷 506-521页

作者： lakshmi PAThAK Kavita ShAh Institute of Environment and Sustainable Development Banaras Hindu UniversityVaranasi 221005India

This paper presents comparative yet extensive analysis of existing non-conventional renewable resources, energy policies and gaps in BRICS countries. An intelligent transformation to green economy to maintain natural resources is noted. Brazil has stable energy policies and is the leading producer of biofuels following hydropower until 2014 but supported wind and solar power development by tendering specific tariffs for energy generation from solar and wind. Russia needs improvement in its legal and regulatory framework with more incentives in energy policies. China is improving upon wind and hydropower but it needs strong policy measures to put cap on increased CO2 emissions. India needs revision in energy policy and requires extra incentives and consumer specific energy policies for research-infrastructure and energy generation technologies. South Africa requires lessons to increase renewable energy and reduce coal mining. Moreover, BRICS countries need to redefine their energy policies based upon their existing geographical, economical, societal and environmental conditions which will help in shaping global energy policies and more financial stability. This paper recognizes the potential of BRICS to reshape the global system paralleled with minimizing CO2 emissions. The concerted role of BRICS needs to be recognized as the leading contributor of global renewable capacity where the developed world is geared and busy to address the environmental issues.

关键词： BRICS CO2 emissions energy policies renewable

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOSSEINI O.BALILAShAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： point source cylindrical cavity porous medium wave-field transformation stress concentration O353.4

Decentralized damage diagnostic technique for tall buildings using VARMAX model

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 417-439页

作者： K.lakshmi J.Prawin CSIR-Structural Engineering Research Centre CSIR RoadChennai 600113Tamil NaduIndia

Civil infrastructure,especially buildings,are becoming more slender,tall,and multipurpose,creating a need to continuously monitor their health to ensure the safety and security of human lives and *** the majority of structural health monitoring techniques use measurements from the entire structure,in this study,an output-only damage diagnostic technique using a decentralized concept(subdomain-based)for tall buildings and employing a vector form of the autoregressive moving average with exogenous input(VARMAX)model is proposed,which offers reduced instrumentation and data handling *** other decentralized approaches,this technique predicts more than one DOF at a time so the number of subdomains required for the diagnosis of the complete structure is *** proposed subdomain-based damage diagnostic algorithm works with ambient loads and does not require any correlated numerical models since it is solely based on measured *** proposed algorithm can identify the time instant of damage,spatial location(s)and characterize the damage *** have been made to account for confounding factors such as environmental and operational variabilities separate from measurement noise to avoid false positive *** effectiveness of the proposed technique is illustrated using synthetic time history responses from a twenty-story framed structure under ambient loading and an experimental study on a ten-story framed *** numerical and experimental investigations confirm the effectiveness of the method and its robustness to environmental/operational variabilities and measurement noise.

关键词： structural health monitoring subdomain high-rise buildings shear-type buildings VARMAX model environmental and operational variability measurement noise