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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

the role of nuclear receptors in regulation of th 17/treg biology and its implications for diseases

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Cellular & Molecular Immunology 2015年第5期12卷 533-542页

作者： benjamin v. Park Fan Pan Immunology and Hematopoiesis Division Department of Oncology Sidney Kimmel Comprehensive Cancer Center Johns Hopkins University School ofMedicine Baltimore MD 21287 USA

Nuclear receptors in the cell play essential roles in environmental sensing, differentiation, development, homeostasis, and metabolism and are thus highly conserved across multiple species. the anti-inflammatory role of nuclear receptors in immune cells has recently gained recognition. Nuclear receptors play critical roles in both myeloid and lymphoid cells, particularly in helper CD4＋ t-cell type 17 （th17） and regulatory t cells （treg）. th17 and treg are closely related cell fates that are determined by orchestrated cytokine signaling. Recent studies have emphasized the interactions between nuclear receptors and the known cytokine signals and how such interaction affects th 17/treg development and function. this review will focus on the most recent discoveries concerning the roles of nuclear receptors in the context of therapeutic applications in autoimmune diseases.

关键词： nuclear receptors regulation

3D Kinematics of Classical Cepheids According to Gaia EDR3 Catalog

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Research in Astronomy and Astrophysics 2023年第4期23卷 1-14页

作者： v.v.Bobylev A.t.Bajkova Pulkovo Astronomical Observatory St.-Petersburg 196140Russia

the kinematics of about 2000 classical Cepheids of the Milky Way with data from Gaia EDR3 catalog has been *** some of these stars,there are line-of-sight *** the basis of the nonlinear rotation model,the parameters of the rotation curve of the Galaxy were *** circular linear rotation velocity of the near-solar neighborhood around the Galaxy center was v0=236±3 km s^(−1) for the assumed Sun's galactocentric distance R0=8.1±0.1 *** of residual velocities of Cepheids based on the linear Ogorodnikov–Milne model showed the presence of the following significantly different from zero gradients:∂U/∂x,∂U/∂z,∂v/∂x,∂v/∂z and∂W/∂x,which behave differently depending on the selection *** most interesting is the gradient∂W/∂x∼−0.5±0.1 km s^(−1) kpc^(−1)(positive rotation of this star system around the Galactic axis y,Ωy)since the velocities W are free of Galactic *** we have an indirect influence of various effects leading to a perturbation of the vertical velocities of the Galactic disk *** on a simpler model,a more accurate estimate of this rotation is obtained,Ωy=0.51±0.07 km s^(−1) kpc^(−1).

关键词： stars distances-Galaxy kinematics and dynamics-stars variables Cepheids

How Common can the Origin of Clusters Cha Ⅰ, Cha Ⅱ, ∈Cha and η Cha be?

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Research in Astronomy and Astrophysics 2024年第5期24卷 28-34页

作者： v.v.Bobylev A.t.Bajkova Pulkovo Astronomical Observatory St.-Petersburg 196140Russia

the trajectories of the groupings η Cha,∈Cha and Cha I,Cha II,constructed backward in time,have been *** concluded that the hypothesis about the joint formation of all four of these clusters from one molecular cloud cannot be completely ***,10–15 Myr ago,all these four clusters were located at approximately the same height above the plane of the ***,the gas-dust clouds from which all these four clusters were formed were located on one broad *** is possible that the appearance of the Cha I,Cha II,∈Cha and η Cha clusters may be associated with the impact on such a front of shock waves formed after supernova explosions in the Scorpius–Centaurus *** estimates of the kinematic ages of the clusters Cha I and Cha II are obtained as 0.12±0.19 and 0.05±0.15,*** is shown that the minimum size of the Cha I-north and Cha I-south clusters corresponded to the time of 0.55±0.24 Myr and 0.04±0.18 Myr ago,respectively,and approximately1.5 Myr ago the distance between the trajectories of these two groupings was minimal.

关键词： stars distances-stars kinematics and dynamics-galaxies star formation

tuning the particle size,physical properties,and photocatalytic activity of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio

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Chinese Physics B 2023年第3期32卷 561-568页

作者： Hung N M Oanh L t M Chung D P thang D v Mai v t Hang L t Minh N v Center for Nano Science and technology Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Department of Physics Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Hanoi University of Mining and Geology Duc Thang WardNorth Tu Liem DistrictHanoi 100000Vietnam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoi 100000Vietnam Faculty of Basic Sciences Hanoi University of Natural Resources and Environment41 A Phu Dien RoadNorth Tu LiemHanoi 100000Vietnam

this study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)*** material characterizations were carried out using x-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive x-ray spectroscopy(EDX),Brunauer–Emmett–teller(BEt)surface area,Fourier transform infrared(FtIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),Uv-vis absorption,and photoluminescence(PL).the results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size *** change is also observed in the Raman scattering and FtIR spectra with the increase in the vibration frequency of the[PO_(4)]*** compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding *** photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light *** is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample.

关键词： morphology photocatalytic Ag^(+)/PO_(4)^(3-)ratio visible light

the Planck theory of Sonoluminescence

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Progress in Natural Science:Materials International 1998年第4期8卷 3-5页

作者： t.v.Prevenslik 2E Greenery Court China Discovery Bay Hong Kong

Sonolummescence (SL) may be explained by a theory, called the Planck theory of SL that treats she bubbles as miniature collapsing cavities. During bubble collapse, the Planck energy intrinsic to the cavity dimensions is converted to microwave photons that accumulate in the bubble wall molecules. Photons are emitted from the bubble wall molecules as the Planck energy accumulates to electronic levels.

关键词： Sonolluninescence Planck theory IRaser.

A micromechanical model for efective conductivity in granular electrode structures

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Acta Mechanica Sinica 2013年第5期29卷 682-698页

作者： Julia Ott benjamin vlker Yixiang Gan Robert M.Mc Meeking Marc Kamlah Institute of Applied Materials Karlsruhe Institute of Technology76131 Karlsruhe Germany Department of Mechanical Engineering University of CaliforniaSanta BarbaraCA 93106 USA School of Civil Engineering The University of SydneyNSW 2006 Australia Materials Department University of CaliforniaSanta BarbaraCA 93106 USA School of Engineering University of AberdeenKing’s CollegeAberdeenAB24 3UE Scotland UK INM-Leibniz Institute for New Materials Campus D22 66123 Saarbrücken Germany

Optimization of composition and microstructure is important to enhance performance of solid oxide fuel cells （SOFC） and lithium-ion batteries （LIB）. For this, the porous electrode structures of both SOFC and LIB are modeled as a binary mixture of electronic and ionic conducting particles to estimate effective transport properties. Particle packings of 10000 spherical, binary sized and randomly positioned particles are created numerically and densified considering the different manufacturing processes in SOFC and LIB： the sintering of SOFC electrodes is approximated geometrically, whereas the calendering process and volume change due to intercalation in LIB are modeled physically by a discrete el- ement approach. A combination of a tracking algorithm and a resistor network approach is developed to predict the con- nectivity and effective conductivity for the various densified structures. For SOFC, a systematic study of the influence of morphology on connectivity and conductivity is performed on a large number of assemblies with different compositions and particle size ratios between 1 and 10. In comparison to percolation theory, an enlarged percolation area is found, es- pecially for large size ratios. It is shown that in contrast to former studies the percolation threshold correlates to varying coordination numbers. the effective conductivity shows not only an increase with volume fraction as expected but also with size ratio. For LIB, a general increase of conductivity during the intercalation process was observed in correlation with increasing contact forces. the positive influence of cal- endering on the percolation threshold and the effective conductivity of carbon black is shown. the anisotropy caused by the calendering process does not influence the carbon black phase.

关键词： Granular electrode structures Effective conductivity - Percolation

Modeling of Canonical Switching Cell Converter Using Genetic Algorithm

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Computer Modeling in Engineering & Sciences 2017年第1期113卷 109-116页

作者： t.v.viknesh v.Manikandan Department of Electrical and Electronics Engineering Coimbatore Institute of TechnologyCoimbatore-641014India

the working of Canonical switching cell(CSC)converter was studied and its equivalent circuit during ON and OFF states were *** space model of CSC converter in ON and OFF states were developed using the Kirchhoff *** state space matrices were used to construct the transfer functions of ON&OFF *** step response of the converter was simulated using *** step response curve was obtained using different values of circuit components(L,C1,C2 and RL)and *** characteristic parameters such as rise time,overshoot,settling time,steady state error and stability were determined using the step response *** response curve shows that there is no overshoot;the rise time and settling time are very low as expected for a converter and its stability is very high but the amplitude is *** circuit was tuned to attain the expected amplitude using PID controller with the help of Genetic *** excellent results of circuits’characteristic parameters are very useful guideline for constructing such CSC converters for DC-DC *** circuit characteristic parameters are useful in constructing such CSC converters for DCDC conversions in driving solar energy using solar panel.

关键词： Canonical switching cell converter state-space methods DC-DC converter step response stability power system modeling switching circuits genetic algorithm PID

the Radcliffe Wave Parameters from Data on Open Star Clusters

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Research in Astronomy and Astrophysics 2024年第3期24卷 106-109页

作者： v.v.Bobylev A.t.Bajkova Pulkovo Astronomical Observatory St-Petersburg 196140Russia

A spectral analysis of the vertical positions and velocities of 374 open star clusters(OSCs)was carried *** took these OSCs from the Hunt and Reffert catalog;they have an average age of about 10 million years,and are located on the galactic plane XY in a narrow zone inclined by 25°to the galactic axis *** following estimates of the parameters of the Radcliffe wave were obtained:(a)the maximum value in periodic perturbations of vertical coordinates Z_(max)=92±10pc with the wavelength of these perturbations λ_(z)=4.82±0.09 kpc;(b)the maximum value of the velocity of vertical disturbances Wmax=4.36±0.12km s^(-1) with disturbance wavelengthλ_(W)=1.78±0.02 *** that the results of the vertical velocity analysis are first-class in accuracy and completely new.

关键词： (Galaxy) local interstellar matter-Galaxy structure-(Galaxy) solar neighborhood