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semantic segmentation of Lumbar Vertebrae Using Meijering U-Net(MU-Net)on spine Magnetic Resonance images

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

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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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Analysis of highly efficient perovskite solar cells with inorganic hole transport material

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Chinese Physics B 2019年第12期28卷 393-399页

作者： i Kabir s A Mahmood Department of Electrical and Electronics Engineering Bangladesh University of Engineering and Technology

Organo-halide perovskites in planar heterojunction architecture have shown considerable promise as efficient light harvesters in solar cells. We carry out a numerical modeling of a planar lead based perovskite solar cell(PsC) with Cu2Znsns4(CZTs) as the hole transporting material(HTM) using the one-dimensional solar cell capacitance simulator(sCAPs-1 D). The effects of numerous parameters such as defect density, thickness, and doping density of the absorber layer on the device performance are investigated. The doping densities and electron affinities of the electron transporting material(ETM) and the HTM are also varied to optimize the PsC performance. it has been observed that a thinner absorber layer of220 nm with a defect density of 1014 cm-3 compared to the reference structure improves the device performance. When doping density of the absorber layer increases beyond 2×1016 cm-3, the power conversion efficiency(PCE) reduces due to enhanced recombination rate. The defect density at the absorber/ETM interface reduces the PCE as well. Considering a series resistance of 5 ?·cm2 and all the optimum parameters of absorber, ETM and HTM layers simultaneously, the overall PCE of the device increases significantly. in comparison with the reference structure, the PCE of the optimized device has been increased from 12.76% to 22.7%, and hence the optimized CZTs based PsC is highly efficient.

关键词： CH3NH3Pbi3 Cu2Znsns4(CZTs) sCAPs-1D absorption coefficient

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Delonix regia and Casuarina equisetifolia as passive biomonitors and as bioaccumulators of atmospheric trace metals

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Journal of Environmental sciences 2010年第7期22卷 1073-1079页

作者： Emmanuel Ehiabhi Ukpebor Justina Ebehirieme Ukpebor Emmanuel Aigbokhan idris Goji Alex Okiemute Onojeghuo Anthony Chinedum okonkwo Air Pollution Research Group Department of ChemistryUniversity of Benin Lancaster Environment Centre Lancaster University Department of Botany University of Benin Federal Ministry of Environment and Housing

The suitability of two common and ubiquitously distributed and exotic ornamental plant species in Nigeria-Delonix regia and Casuarina equisetifolia as biomonitors and as effective bioaccumulators of atmospheric trace metals （Cd, Pb, Zn and Cu） has been evaluated. Bark and leaf samples from these plant species were collected in June and July 2006 at five locations in Benin City. Four of the sampling sites were in areas of high traffic density and commercial activities, the fifth site is a remote site, selected to act as a control and also to provide background information for the metals. The plant samples were collected and processed using standard procedures and trace metals were determined using atomic absorption spectrometer. The bark of the plants was able to bioaccumulate the trace metals, especially Pb which originates from anthropogenic contributions in the city. The Pb range of 20.00-70.00 μg/g measured for the bark samples ofD. regia, exceeded the normal plant Pb concentration of 0.2-20.0 μg/g and most Pb data available in literature. The bark of the plants was observed to accumulate more metals compared to the leave, while D. regia was found to be slightly better than C. equisetifolia in trace metal uptake efficiency. spatial variations in the distributions of Pb and Zn were significant （p 〈 0.05）, and the continuous use of leaded fuel in Nigeria was identified as the predominant source of Pb in the atmosphere.

关键词： passive biomonitors trace metals Delonix regia Casuarina equisetifolia

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Electrical and dielectric characterization of Au/ZnO/n-si device depending frequency and voltage

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Chinese Physics B 2017年第2期26卷 477-483页

作者： i Orak A Kocyigit s Ahndal Bingol University Vocational School of Health Services 12000 Bingol Turkey Bingol University Faculty of Sciences and Arts Department of Physics 12000 Bingol Turkey igdir University Engineering Faculty Department of Electrical Electronic Engineering 76000 Igdir Turkey Gazi Universty Faculty of Sciences Department of Physics 06500 Ankara Turkey

Au/Zn O/n-type si device is obtained using atomic layer deposition（ALD） for Zn O layer, and some main electrical parameters are investigated, such as surface/interface state（Nss）, barrier height（Φb）, series resistance（Rs）, donor concentration（Nd）, and dielectric characterization depending on frequency or voltage. These parameters are acquired by use of impedance spectroscopy measurements at frequencies ranging from 10 k Hz to 1 MHz and the direct current（DC） bias voltages in a range from-2 V to ＋2 V at room temperature are used. The main electrical parameters and dielectric parameters,such as dielectric constant（ε＂）, dielectric loss（ε＂）, loss tangent（tan δ）, the real and imaginary parts of electric modulus（M and M）, and alternating current（AC） electrical conductivity（σ） are affected by changing voltage and frequency. The characterizations show that some main electrical parameters usually decrease with increasing frequency because charge carriers at surface states have not enough time to fallow an external AC signal at high frequencies, and all dielectric parameters strongly depend on the voltage and frequency especially in the depletion and accumulation regions. Consequently, it can be concluded that interfacial polarization and interface charges can easily follow AC signal at low frequencies.

关键词： Au/ZnO/n–si device dielectric properties polarization process frequency and voltage dependence

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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

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Women in visual neural regeneration research

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Neural Regeneration Research 2025年第2期20卷 489-490页

作者： Tonia s.Rex David J.Calkins Vanderbilt Eye institute Vanderbilt University Medical CenterNashvilleTNUSA

The year 2024 marks the 60^(th)anniversary of Title iX and 25 years since the New York Times revealed bias against female faculty members at the Massachusetts institute of *** take an opportunity here to examine the state of gender bias in a relatively new yet already prominent field,neural regeneration in the visual system,for which there is a well-defined context useful for this *** National Eye institute(NEi)provided the first round of research funding for its Audacious Goals initiative(AGi)on visual neural regeneration in 2013 and the last round in ***,we focus on this *** sources included PubMed,the National science Foundation(NsF),the NEi,the Blue Ridge institute for Medical Research and data from the major professional organization for eye and vision research,the Association for Research in Vision and Ophthalmology(ARVO).

关键词： neural visual Times

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Occurrence,distribution and ecological risk assessment of organophosphorus flame retardants and plasticizers in sediment samples along the Vaal River catchment,south Africa

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Emerging Contaminants 2019年第1期5卷 173-178页

作者： Tlou B.Chokwe Jonathan O.okonkwo scientific services Rand WaterP.O.Box 3526Vereeniging1930South Africa Department of Water Environmental and Earth SciencesTshwane University of Technology175 Mandela RoadPretoria0001South Africa

The occurrence,distribution and ecological risk assessment of twelve(12)organophosphorus flame retardants(OPFRs)were investigated in sediments from the Vaal River,south *** halogenated OPFRs[tris-(2-chloroethyl)phosphate(TCEP),three isomers of tris-(chloropropyl)phosphate(TCiPPs),tris-(1,3-dichloro-2-propyl)phosphate(TDCiPP)and tris-(2,3 dibromopropyl)phosphate(TDBPP)]and six non-halogenated OPFRs[tris-(n-butyl)phosphate(TBP),tris-(phenyl)phosphate(TPhP),tris-(butyl ethoxy)phosphate(TBOEP),tris-(2-ethylhexyl)phosphate(TEHP),diphenyl-2-ethylhexyl phosphate(DPEHP)and tris-(m-cresyl)phosphate(m-TCP)]were detected in this *** concentrations of twelve OPFRs in total(s12OPFRs)ranged from 68 to 278 ng g^-1 dry weight(dw)with the mean and median of 138 and 120 ng g^-1;*** non-halogenated OPFRs showed more abundances than the halogenated OPFRs with TDBPP,TBP,and TBOEP the most abundant ***,concentrations of OPFRs in more urbanized region were higher than those in less urbanized *** the concentrations of OPFRs and total organic carbon(TOC)were correlated,a moderate and significant correlation(ps *** risk were estimated and our results showed that m-TCP poses high risk(HQ>1)while TBOEP,TPhP,and TBP posed medium risk(0.1ith the remainder posing negligible risk(HQined in this study provides valuable information on the occurrence and risks of the investigated OPFRs within Vaal River.

关键词： OPFRs Concentrations Risk assessment sediments Vaal river

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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

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Prognostic impact of inflammatory and nutritional biomarkers in pancreatic cancer

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World Journal of Clinical Oncology 2025年第1期16卷 5-9页

作者： Macarena Teja María i Garrido Abrahams Ocanto Felipe Counago Department of Radiation Oncology GenesisCare-San Francisco de Asís University HospitalMadrid 28002Spain Department of Radiation Oncology GenesisCare-Vithas La Milagrosa University HospitalMadrid 28010Spain National Director GenesisCare SpainMadrid 28043Spain Department of Medicine School of MedicineHealth and SportEuropean University of MadridMadrid 28670Spain

Pancreatic cancer is usually associated with a poor *** is the main curative treatment but pancreatic operations are aggressive and new tools that help clinicians to predict surgical and prognostic outcomes are *** et al recently published a retrospective,single centre cohort study evaluating the impact of seven nutritional and inflammatory markers in pancreatic cancer surgical patients:The albumin-to-globulin ratio,prognostic nutritional index(PNi),systemic immune-inflammation index(sii),neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),nutritional risk index,and the geriatric nutritional risk index.A significant correlation was found between the PNi,sii,NLR,and PLR and a hospital discharge of less than 15 *** a univariable analysis,PNi,sii,NLR and PLR were significantly related to recurrence-free survival and,in a multivariable analysis PNi was associated with overall *** meta-analyses corroborate the results in terms of prognosis but individual studies are discordant on their ***,the cut-off values for these markers vary significantly between studies and there are no clinical trials comparing them to identify the most relevant *** are limitations when implementing nutritional and inflammatory biomarkers into clinical practice and further studies are needed in order to answer these questions.

关键词： inflammatory biomarkers Nutritional biomarkers Pancreatic cancer Prognosis surgical complications

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