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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

New frontiers in liver ultrasound:From mono to multi parametricity

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World Journal of Gastrointestinal Oncology 2021年第10期13卷 1302-1316页

作者： tommaso vincenzo bartolotta Adele taibbi Angelo Randazzo Cesare Gagliardo Department of Radiology University Hospital"Paolo Giaccone"Palermo 90127Italy Radiology Department Fondazione Istituto G.Giglio HospitalCefalù90015Italy Department of Biopathology and Medical and Forensic Biotechnologies University of PalermoPalermo 90127Italy

Modern liver ultrasonography(US)has become a“one-stop shop”able to provide not only anatomic and morphologic but also functional information about vascularity,stiffness and other various liver tissue *** US techniques allow a quantitative assessment of various liver *** scanning is no more limited to the visualized plane,but three-dimensional,volumetric acquisition and consequent post-processing are also ***,US scan can be consistently merged and visualized in real time with Computed tomography and Magnetic Resonance Imaging *** and safe microbubble�based contrast agents allow a real time,dynamic study of contrast kinetic for the detection and characterization of focal liver *** can be used to guide loco-regional treatment of liver malignancies and to assess tumoral response either to interventional procedures or medical *** may also carry and deliver drugs under ultrasound *** plays a crucial role in diagnosing,treating and monitoring focal and diffuse liver *** the basis of personal experience and literature data,this paper is aimed to review the main topics involving recent advances in the field of liver ultrasound.

关键词： Ultrasonography Contrast-enhanced ultrasound Elastography Interventional Doppler ultrasonography

New advances in radiomics of gastrointestinal stromal tumors

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World Journal of Gastroenterology 2020年第32期26卷 4729-4738页

作者： Roberto Cannella Ludovico La Grutta Massimo Midiri tommaso vincenzo bartolotta Section of Radiology-BiND University Hospital“Paolo Giaccone”Palermo 90127Italy Department of Radiology Fondazione Istituto Giuseppe GiglioCt.da PietrapollastraCefalù(Palermo)90015Italy

Gastrointestinal stromal tumors(GISts)are uncommon neoplasms of the gastrointestinal tract with peculiar clinical,genetic,and imaging *** knowledge of risk stratification and mutational status is crucial to guide the appropriate patients’*** the clinical behavior and biological aggressiveness of GISts based on conventional computed tomography(Ct)and magnetic resonance imaging(MRI)evaluation is challenging,unless the lesions have already metastasized at the time of *** is emerging as a promising tool for the quantification of lesion heterogeneity on radiological images,extracting additional data that cannot be assessed by visual *** applications have been explored for the differential diagnosis of GISts from other gastrointestinal neoplasms,risk stratification and prediction of prognosis after surgical resection,and evaluation of mutational status in *** published researches on GISts radiomics have obtained excellent performance of derived radiomics models on Ct and ***,lack of standardization and differences in study methodology challenge the application of radiomics in clinical *** purpose of this review is to describe the new advances of radiomics applied to Ct and MRI for the evaluation of gastrointestinal stromal tumors,discuss the potential clinical applications that may impact patients’management,report limitations of current radiomics studies,and future directions.

关键词： Gastrointestinal stromal tumors Radiomics texture analysis Computed tomography Magnetic resonance imaging Clinical applications

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

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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

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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

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Loco-regional treatment of hepatocellular carcinoma:Role of contrast-enhanced ultrasonography

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World Journal of Hepatology 2022年第5期14卷 911-922页

作者： Agostino Inzerillo Maria Franca Meloni Adele taibbi tommaso vincenzo bartolotta Department of Radiology University Hospital"Paolo Giaccone"Palermo 90127Italy Department of Radiology Casa di Cura IgeaMilan 20121Italy Department of Radiology Fondazione Istituto G.Giglio HospitalCefalù90015Italy

Hepatocellular carcinoma(HCC)is one of the few cancers for which locoregional treatments(LRts)are included in international guidelines and are considered as a valid alternative to conventional *** to Barcelona Clinic Liver Cancer classification,percutaneous treatments such as percutaneous ethanol injection,radiofrequency ablation and microwave ablation are the therapy of choice among curative treatments in patients categorized as very early and early stage,while transcatheter arterial chemoembolization is considered the better option for intermediate stage HCC.A precise assessment of treatment efficacy and surveillance is essential to optimize survival rate,whereas residual tumor requires additional *** modalities play a key role in this ***,contrast-enhanced computed tomography/magnetic resonance imaging are considered the standard imaging modalities for this *** enhanced ultrasound(CEUS),using second generation contrast agents,plays an increasingly important role in detecting residual disease after *** is a straightforward to perform,repeatable and cost-effective imaging modality for patients with renal failure or iodine *** to the ability to focus on single regions,CEUS can also provide high temporal ***,several studies have reported the same or better diagnostic accuracy as contrast-enhanced computed tomography for assessing tumor vascularity 1 mo after LRts,and recently three-dimensional(3D)-CEUS has been reported as a promising technique to improve the evaluation of tumor response to ***,CEUS could be used early after procedures in monitoring HCC treatments,but nowadays this indication is still debated,and data from literature are conflicting,especially after transcatheter arterial chemoembolization procedure.

关键词： Hepatocellular carcinoma Contrast-enhanced ultrasonography Radiofrequency ablation transcatheter arterial chemoembolization Ultrasound Liver

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.

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