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Defence Technology（防务技术） 2019年第1期15卷 111-121页

作者： c.v.s.murthy A.Gopala Krishna G.M.Reddy Defence Research and Development Laboratory Jawaharlal Nehru Technological University Defence Metallurgical Research Laboratory

Maraging steel (250) and 13-8 Mo stainless steel plates were joined by gas tungsten constricted arc welding(GTcAW) process in similar and dissimilar metal combinations using 13-8 Mo stainless steel filler wire. The similar and dissimilar metal welds made in solutionized condition were subjected to standard post weld hardening treatments direct ageing at 485 ℃, soaking for 31/2 hours followed by air cooling(ageing treatment of maraging steel) and direct ageing at 510 ℃, soaking for 4 h followed by air cooling(ageing treatment of 13-8 Mo stainless steel). The joint characterization studies include microstructure examination, microhardness survey across the weldments and transverse weld tensile *** and dissimilar metal weldments responded to both the post weld ageing treatment. After post weld aging, increase in yield strength, UTs and slight reduction in % elongation of similar and dissimilar metal were observed. The observed tensile properties were correlated with microstructure and hardness distribution across the welds.

关键词： Maraging steel(250) 13-8 Mo stainless steel Mechanical properties Microstructure

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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FINITE DIFFERENcE METHODs FOR THE HEAT EQUATION WITH A NONLOcAL BOUNDARY cONDITION

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Journal of computational Mathematics 2015年第1期33卷 17-32页

作者： v. Thomee A.s. vasudeva murthy Mathematical sciences Chalmers University of Technology and University of Gothenburg SE-412 96 GSteborg Sweden TIFR centre for Appl. Math Yelahanka New Town Bangalore India

We consider the numerical solution by finite difference methods of the heat equation in one space dimension, with a nonlocal integral boundary condition, resulting from the truncation to a finite interval of the problem on a semi-infinite interval. We first analyze the forward Euler method, and then the 0-method for 0 〈 θ ≤ 1, in both cases in maximum-norm, showing O（h2 ＋ k） error bounds, where h is the mesh-width and k the time step. We then give an alternative analysis for the case θ= 1/2, the crank-Nicolson method, using energy arguments, yielding a O（h2 ＋ k3/2） error bound. special attention is given the approximation of the boundary integral operator. Our results are illustrated by numerical examples.

关键词： Heat equation Artificial boundary conditions unbounded domains productquadrature.

some hydrodynamic aspects of 3-phase inverse fluidized bed

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china Particuology 2007年第5期5卷 351-356页

作者： Krishna s.v.s.R. Bandaru D.v.s. murthy K. Krishnaiah Department of chemical Engineering Indian Institute of Technology Madras

Hydrodynamics of 3-phase inverse fluidized bed is studied experimentally using low density particles for different liquid and gas velocities. The hydrodynamic characteristics studied include pressure drop, minimum liquid and gas fluidization velocities and phase holdups. The minimum liquid fluidization velocity determined using the bed pressure gradient, decreases with increase in gas velocity. The axial profiles of phase holdups shows that the liquid holdup increases along the bed height, whereas the solid holdup decreases down the bed. However, the gas holdup is almost uniform in the bed.

关键词： Inverse fluidization Inverse fluidized bed Hydrodynamics Phase holdup Axial holdup

Development of a drill energy utilization index for aiding selection of drill machines in surface mines

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International Journal of Mining science and Technology 2017年第3期27卷 393-399页

作者： Kumar suraj Rahul Talreja murthy v.M.s.R. Department of Mining Engineering Indian School of Mines Dhanbad India

Drill machines used in surface mines, particularly in coal, is characterized by a very poor utilization （around 40%） and low availability （around 60%）. The main purpose of this study is to develop a drill selec- tion methodology and simultaneously a performance evaluation technique based on drill cuttings produced and drilling rate achieved. In all 28 blast drilled through were investigated. The drilling was accomplished by 5 different drill machines of Ingersoll-Rand and Revathi working in coal mines of sonepur Bazari （sEcL） and Block-II （BccL）. The drills are Rotary and Rotary Percussive type using tri- cone rock roller bits. Drill cuttings were collected and sieve analysis was done in the laboratory. Using Rosin Ramler Diagram, coarseness index （cI）, mean chip size （d）, specific-st trace area （ssA） and charac- teristic particle size distribution curves for all the holes drilled were plotted. The predictor equation for drill penetration rate established through multiple regressions was found to have a very good correlation with an index of determination of 0.85. A comparative analysis of particle size distribution curves was used to evaluate the drill efficiency. The suggested approach utilises the area under the curve, after the point of trend reversal and brittleness ratio of the respective bench to arrive at drill energy utilization index （DEUI）, for mapping of drill machine to bench, The developed DEU1 can aid in selecting or mapping a right machine to right bench for achieving higher penetration rate and utilizations.

关键词： Drill cutting parameter coarseness index Mean chip size specific surface area Particle size distribution curves Drill energy ptilization index

synergistic effect of nano-silica slurries for cementing oil and gas wells

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Petroleum Research 2020年第1期5卷 83-91页

作者： R.v.v.Ramana murthy murthy chavali Faruq Mohammad Division of chemistry Department of Sciences and HumanitiesVignan’s Foundation for ScienceTechnology and Research University(Vignan’s University)Vadlamudi 522213 Guntur DistrictAndhra PradeshIndia b PG Department of chemistry Dharma Appa Rao CollegeNuzvid 521201 Krishna DistrictAndhra PradeshIndia shree velagapudi Ramakrishna Memorial college(svRMc-PG studies) NAAC’A’Grade&ISO 9001:2015 Certified(Autonomous)Nagaram 522268 Guntur DistrictAndhra PradeshIndia McETRc TenaliGuntur 522201 Andhra PradeshIndia surfactants Research chair King Saud UniversityCollege of ScienceRiyadh 11451 Kingdom of Saudi Arabia

Nanosilica,when combined with cement slurry aids in improving its compressive strength even,reduces the wait-on-cement time for cement *** study focuses on the synergistic effect of nano-silica in oil and gas well cementing.A comparative study is conducted on the performance of cement slurry(conventional 118 pcf(15.8 lbm/gal))with nanosilica and cement slurry without *** cement slurry combined with nano-silica has shown an early compressive strength development in cement slurry at different concentration of silica fume at 10% and 20% by weight of *** study also focuses on other areas for improvement including slurry stability,free fluid reduction,lower fluid loss value,fine rheology,appropriate thickening time and higher ultimate compressive strength *** cement slurry with nano-silica has shown improvement in the compressive strength due to the increased rate of hydration,thus thickening time was within 5hrs.

关键词： Nanosilica Thickening time compressive strength Ultrasonic cement analyzer

Effect of cadmium on the Hatching ofMetaphire posthuma cocoons

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Biomedical and Environmental sciences 1999年第1期12卷 50-53页

作者： s·K·GUPTA R·c·murthy 等 IndustrialToxicologyResearchcentre

Earthworms are considered ideal soil organisms for use in terrestrial ecotoxicology. Due to theirsusceptibility of heavy metals, the effect of cadmium on the hatching of M. posthuma cocoons wasstudied. The hatching was observed by the water incubation method and the doses of cd were 0,1.25, 2.5, 5.0, 10.0 and 40.0ppm. The0 and 1.25 ppm treated cocoons hatched within 45-60 days at 20℃ with 80% hatching rate and one juvenile per cocoon; no hatching was observed athigher concentrations. Furihermore, there was a linear increase in cd residue in the treated co-coons. These results are apparently ill effects of cd on embryonic development of the earthworms

关键词： Animals cadmium Oligochaeta soil Pollutants

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