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Defence Technology（防务技术） 2016年第5期12卷 380-387页

作者： s.v.s. narayana murty sushant K. MANWATKAR E Ramesh narayanaN Material Characterization Division Materials and Metallurgy Group Vikram Sarabhai Space Centre Trivandrum 695 022 India

Maraging steels have excellent combination of strength and toughness and are extensively used for a variety of aerospace applications. In one such critical application, this steel was used to fabricate shear screws of a stage separation system in a satellite launch vehicle. During assembly preparations, one of the shear screws which connected the separation band and band end block has failed at the first thread. Microstructural analysis revealed that the crack originated from the root of the thread and propagated in an intergranular mode. The failure is attributed to combined effect of stress and corrosion leading to stress corrosion cracking.

关键词： M250 grade maraging steel shear screw separation system Mermen band stress corrosion cracking

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

Unlocking hypoglycemia–associated brain microvascular dysfunction:critical insights from proteomic analysis

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Neural Regeneration Research 2025年第6期20卷 1707-1708页

作者： siva s.v.P.sakamuri Anil sakamuri Department of Chemistry Auburn University at MontgomeryMontgomeryALUSA vascular Biology Center and Department of Medicine Medical College of Georgia at Augusta UniversityAugustaGAUSA

Hypoglycemia-a critical complication linked to worsened brain function in diabetic subjects:Hypoglycemia is characterized by a decline in circulatory glucose levels below sta nda rd physiological *** hypoglycemia,classified as level 1 hypoglycemia,is defined by blood glucose levels below 70 mg/dL and can be effectively addressed through carbohydrate *** hypoglycemia,denoted by blood glucose levels less than 54 mg/dL,poses a life-threatening risk if left *** with type 1 and type 2 diabetes undergoing insulin treatment are particularly susceptible to hypoglycemia due to impaired counterregulatory mechanisms.

关键词： impaired intake critical

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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Microstructure and texture evolution in AZ31 magnesium alloy during caliber rolling at different temperatures

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Journal of Magnesium and Alloys 2017年第3期5卷 340-347页

作者： Abhishek Tripathi s.v.s.narayana murty P.Ramesh narayanan Department of Metallurgical Engineering and Materials science Indian Institute of Technology BombayMumbai 400076India Materials Characterisation Division Materials and Metallurgy GroupVikram Sarabhai Space CentreTrivandrum 695022India

Magnesium alloy AZ31 was caliber rolled at different temperatures viz.523K,573K,623K,673K and 723K imposing a total cumulative reduction of 92%and a cumulative strain of *** associated microstructure and texture evolution were studied using Electron Back scattered Diffraction(EBsD)and X-ray macro-texture observations *** refinement was observed in all the caliber rolled bars indicating the occurrence of dynamic *** parameter and texture index were used to study the evolution of *** doubling of the yield strength at room temperature was observed by caliber rolling at a temperature of *** improvement in mechanical properties was explained on the basis of the fine grain microstructures and suitable development of crystallographic *** on the present study,warm caliber rolling can be used as a good production method for obtaining long bars of high strength magnesium alloy AZ31.

关键词： Magnesium alloy AZ31 Microstructure Caliber rolling Texture

Microstructure, properties and hot workability of M300 grade maraging steel

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Defence Technology（防务技术） 2018年第1期14卷 51-58页

作者： K.v.A.Chakravarthi N.T.B.N.Koundinya s.v.s.narayana murty B.Nageswara Rao Materials and Mechanical Entity Vikram Sarabhai Space Centre Research scholar Department of Mechanical Engineering K L University Department of Metallurgical Engineering and Materials science Indian Institute of Technology Department of Mechanical Engineering K L University

This paper presents isothermal uniaxial compression test results of M300 grade maraging steel over a wide range of temperatures(900 e1200℃) and strain rates(0.001 e100 s^(-1)) to examine hot deformability and concurrent microstructural evolution. Processing map is generated and indicated the optimum processing parameters in the temperature range of 1125℃-1200℃ and strain rate range of 0.001 e0.1 s^(-1). High values of the efficiency of power dissipation, microstructural observations and EBsD results indicate softening mechanism to be the occurrence of dynamic recrystallisation. Material constants in a constitutive relation are evaluated from the flow stress data useful in computer modelling.

关键词： Activation energy Constitutive relation Hot deformation M300 grade maraging steel Processing map

Convergence of COvID-19 and recurrent stroke:In-hospital mortality risks explored

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World Journal of virology 2025年第1期14卷 5-8页

作者： Basavraj s Nagoba shree v Dhotre Ajay M Gavkare sachin s Mumbre Pradnya s Dhotre Department of Microbiology Maharashtra Institute of Medical Sciences and Research(Medical College)Latur 413531India Department of Microbiology Ashwini Rural Medical CollegeSolapur 413001India Department of Community Medicine Ashwini Rural Medical CollegeSolapur 413001India Department of Biochemistry Ashwini Rural Medical CollegeSolapur 413001India

This editorial comments on the article by Desai et al,which investigates the impact of coronavirus disease 2019(COvID-19)on in-hospital mortality among patients with recurrent stroke using data from the 2020 National Inpatient *** findings reveal significantly higher mortality rates in COvID-19-positive patients compared to non-COvID-19 patients,particularly among middle-aged individuals,males,and ethnic *** editorial explores the underlying mechanisms contributing to these outcomes and discusses the clinical implications for targeted management strategies in high-risk *** results emphasize the need for comprehensive approaches to mitigate the heightened risks faced by recurrent stroke patients during the COvID-19 pandemic.

关键词： Recurrent stroke COvID-19 In-hospital mortality Nationwide analysis stroke admissions Infectious diseases Chronic health conditions Hypercoagulability

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

Multi-objective energy management in microgrids with hybrid energy sources and battery energy storage systems

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Protection and Control of Modern Power systems 2020年第1期5卷 1-20页

作者： v.v.s.N.murty Ashwani Kumar Electrical Engg Department NIT KurukshetraKurukshetraHaryanaIndia

Microgrid with hybrid renewable energy sources is a promising solution where the distribution network expansion is unfeasible or not *** of renewable energy sources provides energy security,substantial cost savings and reduction in greenhouse gas emissions,enabling nation to meet emission *** energy management is a challenging task for microgrid operator(MGO)for optimal energy utilization in microgrid with penetration of renewable energy sources,energy storage devices and demand *** this paper,optimal energy dispatch strategy is established for grid connected and standalone microgrids integrated with photovoltaic(Pv),wind turbine(WT),fuel cell(FC),micro turbine(MT),diesel generator(DG)and battery energy storage system(Ess).Techno-economic benefits are demonstrated for the hybrid power *** far,microgrid energy management problem has been addressed with the aim of minimizing operating cost ***,the issues of power losses and environment i.e.,emission-related objectives need to be addressed for effective energy management of microgrid *** this paper,microgrid energy management(MGEM)is formulated as mixedinteger linear programming and a new multi-objective solution is proposed for MGEM along with demand response *** response is included in the optimization problem to demonstrate it’s impact on optimal energy dispatch and techno-commercial *** interface has been developed for optimal scheduling of *** results are obtained for the optimal capacity of Pv,WT,DG,MT,FC,converter,BEs,charging/discharging scheduling,state of charge of battery,power exchange with grid,annual net present cost,cost of energy,initial cost,operational cost,fuel cost and penalty of greenhouse gases *** results show that CO_(2) emissions in standalone hybrid microgrid system is reduced by 51.60%compared to traditional system with grid *** results obtained with the proposed method is comp

关键词： Microgrid energy management Renewable energy sources storage system Demand response

Effects of caliber rolling on microstructure and room temperature tensile properties of Mge3Ale1Zn alloy

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Journal of Magnesium and Alloys 2013年第2期1卷 169-175页

作者： R.L.Doiphode s.v.s.narayana murty N.Prabhu B.P.Kashyap Department of Metallurgical Engineering and Materials science Indian Institute of Technology BombayMumbai 400076India special Materials Division Vikram Sarabhai Space CenterISROTrivandrum 695022India

Mge3Ale1Zn(AZ31)alloy was caliber rolled isothermally in the temperature range of 250e450C to develop fine grains of 3.6e12.5 *** stressestrain curves obtained from tensile tests at room temperature were found to vary with the temperature employed in caliber *** tensile strength of 290 MPa and ductility of 13.5%were obtained upon caliber rolling at 300C as compared to 188 MPa and 15.2%,respectively,in the mill-rolled *** variations in tensile properties are explained by the concomitant grain size,texture and twins obtained as a function of caliber rolling temperature.

关键词： AZ31 Mg-alloy Caliber rolling Twinning Grain size Tensile properties