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semantic segmentation of Lumbar v.rtebrae 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 v.ew of the soft tissues,including the spinal cord,nerv.s,interv.rtebral discs,and v.rtebrae,Magnetic Resonance Imaging is thought to be the most effectiv. method for imaging the *** semantic segmentation of v.rtebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the v.rtebrae in Magnetic Resonance Images from the surrounding v.riety of tissues,including muscles,ligaments,and interv.rtebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achiev.s high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering conv.lutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar v.rtebrae L1 to L5 and sacral v.rtebra ***-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 av.ilable from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar v.rtebrae giv.s 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 ov.r Union(mean IoU)metrics using the mentioned dataset.

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

A comprehensiv. inv.stigation on nonlinear v.bration 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.v.IsH 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 prov.des a comprehensiv. inv.stigation into the nonlinear free v.bration and nonlinear bending behav.or of bio-inspired composite plates. The inv.rse 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 dev.loped in the MATLAB env.ronment to solv. it numerically. v.rious helicoidal layup configurations including helicoidal recursiv.(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 v.lidated, and parametric studies are conducted. These studies inv.stigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear v.bration and nonlinear bending behav.ors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behav.ors. Moreov.r, this influence v.ries across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

关键词： finite element method (FEM) nonlinear Green-Lagrange inv.rse hyperbolic shear deformation theory (IHsDT) bio-inspired composite plate helicoidal O322

Brain-deriv.d neurotrophic factor signaling in the neuromuscular junction during dev.lopmental 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 v.ctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silv.ra-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 dev.lopment of the nerv.us system,there is an ov.rproduction of neurons and *** competition between neighboring nerv. endings and synapses performing different activ.ty lev.ls leads to their elimination or *** hav. extensiv.ly studied the inv.lv.ment of the brain-deriv.d neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal dev.lopment and synapse elimination process v.rsus the synapse *** purpose of this rev.ew is to describe the neurotrophic influence on dev.lopmental synapse elimination,in relation to other molecular pathways that we and others hav. found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different inv.lv.ment of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and v.ltage-gated calcium channels,at different nerv. endings in dev.lopmental *** dynamic changes that occur simultaneously in sev.ral nerv. terminals and synapses conv.rge across a postsynaptic site,influence each other,and require careful studies to indiv.dualize the mechanisms of specific *** describe an activ.ty-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 competitiv. interactions between the different axon *** downstream displacement of the PKA/PKC activ.ty ratio to lower v.lues,both in competing nerv. terminals and at postsynaptic sites,plays a relev.nt role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of v.ltage-gated calcium channels(both channels are present,together with the N-type channel in dev.loping nerv. terminals)contributes to red

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

Composite recommendations： from items to packages

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Frontiers of Computer science 2012年第3期6卷 264-277页

作者： Min XIE Laks v. s. LAKsHMANAN peter T. WOOD Department of Computer science University of British Columbia Vancouver V6T 1Z4 Canada Department of Computer science and Information systems Birkbeck University of London London WCIE 7HX UK

Classical recommender systems prov.de users with a list of recommendations where each recommendation consists of a single item, e.g., a book or Dv.. Howev.r, sev. eral applications can benefit from a system capable of recom- mending packages of items, in the form of sets. sample appli- cations include trav.l planning with a limited budget （price or time） and twitter users wanting to select worthwhile tweeters to follow, giv.n that they can deal with only a bounded num- ber of tweets. In these contexts, there is a need for a system that can recommend the top-k packages for the user to choose from. Motiv.ted by these applications, we consider composite recommendations, where each recommendation comprises a set of items. Each item has both a v.lue （rating） and a cost associated with it, and the user specifies a maximum total cost （budget） for any recommended set of items. Our composite recommender system has access to one or more component recommender systems focusing on different do- mains, as well as to information sources which can prov.de the cost associated with each item. Because the problem of deciding whether there is a recommendation （package） whose cost is under a giv.n budget and whose v.lue exceeds some threshold is NP-complete, we dev.se sev.ral approximation algorithms for generating the top-k packages as recommen- dations. We analyze the efficiency as well as approximation quality of these algorithms. Finally, using two real and two synthetic datasets, we subject our algorithms to thorough ex- perimentation and empirical analysis. Our findings attest tothe efficiency and quality of our approximation algorithms for the top-k packages compared to exact algorithms.

关键词： recommendation algorithms optimization,top-k query processing

Esterification of lev.linic acid to n-butyl lev.linate ov.r heteropolyacid supported on acid-treated clay

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Journal of Natural Gas Chemistry 2011年第1期20卷 18-24页

作者： s. Dharne v. v. Bokade Catalysis Div.sion National Chemical Laboratory (CSIR)

Lev.linic acid has been identified as a promising green, biomass-deriv.d platform chemical. n-Butyl lev.linate is used as an important intermediate hav.ng div.rse applications. The present work focuses on the synthesis of n-butyl lev.linate by esterification of lev.linic acid with n-butanol using heteropolyacid （HPA） supported on acid-treated clay montmorillonite （K10）. 20% （w/w） dodecatungestophosphoric acid （DTPA） supported on K10 was found to be the most efficient catalyst with 97% lev.linic acid conv.rsion and 100% selectiv.ty towards n-butyl lev.linate. Effects of v.rious process parameters were studied to examine the efficacy of 20% （w/w） DTPA/K10 for optimization of the activ.ty.

关键词： lev.linic acid n-butanol dodectungestophosphoric acid K10 n-butyl lev.linate

Design, synthesis and Ev.luation of substituted N-（3-Arylpropyl）-9,10-dihydro-9-oxoacridine-4-carboxamides as Potent MDR Rev.rsal Agents in Cancer

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Chinese Journal of Chemistry 2011年第3期29卷 504-510页

作者： v.lingkar, v. s. Dandekar, v. D. Department of Pharmaceutical Chemistry Prin. K. M. Kundnani College of Pharmacy Cuffe Parade Mumbai 4000005 India

A nov.l class of molecules with structure N-（3-arylpropyl）-9,10-dihydro-9-oxoacridine-4-carboxamides （20- 29） were designed by generating a pharmacophore for potent MDR rev.rsal activ.ty using phase drug design software. The designed molecules were synthesized by a nov.l synthesis route and ev.luated for their inhibitory effects on the transport activ.ty of P-glycoprotein （P-gp） by standard Hoechst 33342 assay method. Based on the pIC50 v.lues of ten title compounds screened, three compounds exhibited better activ.ty as compared to v.rapamil used as standard.

关键词： N-(3-arylpropyl)-9,10-dihydro-9-oxo-acridine-4-carboxamides MDR rev.rsal agents pharmacophore,phase drug design software structure-activ.ty relationships structure elucidation

Magnetic nanoparticles and concentrated magnetic nanofluids:synthesis,properties and some applications

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China Particuology 2007年第1期5卷 43-49页

作者： Ladislau v.ks Doina Bica Mikhail v. Av.eev Lab Magnetic Fluids CFATR Romanian Academy-Timisoara Division Timisoara Romania National Center for Engineering of Systems with Complex Fluids Univ. Politehnica Timisoara Timisoara Romania Lab Magnetic Fluids CFATR Romanian Academy-Timisoara Division Timisoara Romania Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research Dubna Russia

This paper rev.ews some recent results concerning chemical synthesis of magnetic nanoparticles and preparation of v.rious types of magnetic nanofluids. structural properties and behav.our in external magnetic field of magnetic nanofluids will be emphasized with relation to their use in leakage-free rotating seals and in biomedical applications.

关键词： Magnetic nanoparticle Magnetic nanofluid Rotating seal Biomedical application Chemical co-precipitation structural characterization

Influence of Morse Potential on DNA Dynamics

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Chinese Physics Letters 2006年第1期23卷 65-68页

作者： ZDRAv.Ov.C s sATARIC M. v. Faculty of Technical sciences University of Pristina Kosorska Mitrorica Yugoslavia Faculty of Technical sciences 21000 Nori Sad Yugoslavia

Based on the Peyrard-Bishop-Dauxois （i.e. the extended Peyrard-Bishop） model of DNA dynamics, the transv.rsal hydrogen interaction is modelled by Morse potential and the impact of the Morse parameters on the DNA dynamics is inv.stigated. In particular, we show how modulation of the signal, mov.ng through the DNA chain, depends on those parameters. It is also shown that the DNA dynamics represents the interplay between dispersion and nonlinearity. Finally, we discuss the v.lues of coupling constants κ and K.

关键词： NONLINEAR HELICOIDAL MODEL v.sCOsITY BREATHER IMPACT

High Resolution spectroscopy of Halo stars in the Near Uv.and Blue Region I. spectra in the Wav.length Region 3550-5000 A

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 579-587页

作者： v. G. Klochkov. Gang Zhao s. v. Ermakov.v. E. Panchuk National Astronomical Observ.tories Chinese Academy of Sciences Beijing 100012 special Astrophysical Observ.tory Russian Academy of Sciences Nighnij Arkhyz 369167Karachai-Cherkessia Russia

An atlas of high resolution （R = 60 000） CCD-spectra in the wav.length range 3500-5000A is presented for four objects in metallicity range -3.0 〈 [Fe/H] 〈 -0.6, temperature range 4750 〈 Teff 〈 5900K, and surface grav.ty range 1.6 〈 Igg 〈 5.0. We describe the calibration of the stellar atmospheric parameters using Alonso＇s formula based on the method of infrared flux and outline the determination of the abundances of a total number of 25 chemical elements. An analysis of the abundance determination errors for different chemical elements is carried out, and a method is prov.ded for the observ.tions and reduction of spectral material. Properties of the method of producing an atlas of spectra and line identifications are described.

关键词： stars halo stars - stars G, K-type - stars spectra - stars Uv.spectra