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Electrostatic switch of magnetic core-shell in 0-3 type LSMO/PZT composite film
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作者 Bo Chen Zi-Run Li +1 位作者 Chuan-Fu Huang Yong-Mei Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第9期523-528,共6页
By dispersing La1-xSrxMnO3 (LSMO) granule into PbZrxTi1-xO3 (PZT) matrix, the 0-3 type LSMO/PZT composite film is synthesized through chemical solution method. The asymmetry of the top and bottom electrodes introduces... By dispersing La1-xSrxMnO3 (LSMO) granule into PbZrxTi1-xO3 (PZT) matrix, the 0-3 type LSMO/PZT composite film is synthesized through chemical solution method. The asymmetry of the top and bottom electrodes introduces novel electrostatic screening on LSMO/PZT interface. As electric polarization is switched between upward and downward orientations, the evolution of exchange bias, diode transport, and magnetoresistance is observed. The result implies the electrostatic switch of magnetic core-shell in the present film. In detail, as the spontaneous polarization is upward or downward in the PZT matrix, the ferromagnetic/antiferromagnetic or ferromagnetic/ferromagnetic core-shell structure is formed in LSMO granule, respectively. This work would develop a novel device for spintronics and metamaterial. 展开更多
关键词 electric polarization magnetic core-shell exchange bias CONDUCTANCE
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Porous TiO2-coated Magnetic Core-Shell Nanocomposites:Preparation and Enhanced Photocatalytic Activity 被引量:10
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作者 刘鸿飞 季生福 +2 位作者 郑园园 李明 杨浩 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第5期569-576,共8页
The core-shell structured TiO2/SiO2 @Fe3O4 photocatalysts were prepared using Fe3O4 as magnetic core,tetraethoxysilane(TEOS) as silica source and tetrabutyl titanate(TBOT) as titanium sources.The as-obtained struc... The core-shell structured TiO2/SiO2 @Fe3O4 photocatalysts were prepared using Fe3O4 as magnetic core,tetraethoxysilane(TEOS) as silica source and tetrabutyl titanate(TBOT) as titanium sources.The as-obtained structure was composed of a SiO2@Fe3O4 core and a porous TiO2 shell.The diameter of SiO2@Fe3O4 core was about 205 nm with thickness of porous TiO2 of about 5-6 nm.The 9%TiO2/6%SiO2@Fe3O4 microspheres possess the highest BET surface area and the BJH pore volume,which are 373.5 m2.g-1 and 0.28 cm3.g-1,respectively.The 9%TiO2/6%SiO2@Fe3O4 photocatalyst exhibited an excellent performance for the degradation of methyl orange and methylene blue dyes.Two different dyes were completely decolorized in 60 min under UV irradiation.The photocatalytic activity and the amount of catalyst were almost not decrease after recycling for 6 times by using external magnetic field. 展开更多
关键词 PHOTOCATALYST magnetic microspheres porous TiO2 DYESTUFF DEGRADATION
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Magnetic core-shell microparticles for oil removing with thermal driving regeneration property 被引量:1
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作者 Shi-Hao Chen Chuan-Lin Mou +3 位作者 Wen-Long Ma Ya-Dong Li Zi-Yu Tang Hong-Bo Deng 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2531-2544,共14页
Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to pr... Here, we report the construction of magnetic core-shell microparticles for oil removal with thermal driving regeneration property. Water-in-oil-in water (W/O/W) emulsions from microfluidics are used as templates to prepare core-shell microparticles with magnetic holed poly (ethoxylated trimethylolpropane triacrylate) (PETPTA) shells each containing a thermal-sensitive poly (N-Isopropylacrylamide) (PNIPAM) core. The microparticles could adsorb oil from water due to the special structure and be collected with a magnetic field. Then, the oil-filled microparticles would be regenerated by thermal stimulus, in which the inner PNIPAM microgels work as thermal-sensitive pistons to force out the adsorbed oil. At the same time, the adsorbed oil would be recycled by distillation. Furthermore, the adsorption capacity of the microparticles for oil keeps very stable after 1st cycle. The adsorption and regeneration performances of the microparticles are greatly affected by the size of the holes on the outer PETPTA shells, which could be precisely controlled by regulating the interfacial forces in W/O/W emulsion templates. The optimized core-shell microparticles show excellent oil adsorption and thermal driving regeneration performances nearly without secondary pollution, and would be a reliable green adsorption material for kinds of oil. 展开更多
关键词 MICROFLUIDICS core-shell microparticles Thermal driving regeneration Secondary pollution Oil adsorption
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Preparation of magnetic core-shell Ce-doped zirconia and its As(Ⅲ)adsorption properties
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作者 Ming-han DU Hong YANG +7 位作者 Weng FU Yan-ling HU Huan TAO Jia-xi FAN Ying LIU Yu-fan CHEN Na-er DILI Xiao-qing LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第12期4156-4170,共15页
A new magnetic mesoporous As(Ⅲ)adsorbent of Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)was prepared by solvothermal and sol^(-)gel method.The core-shell adsorbent presented a high specific surface area(168.2 m^(2)/g)and fast magn... A new magnetic mesoporous As(Ⅲ)adsorbent of Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)was prepared by solvothermal and sol^(-)gel method.The core-shell adsorbent presented a high specific surface area(168.2 m^(2)/g)and fast magnetic separation performance(5.37 A·m^(2)/kg).Compared with Fe_(3)O_(4)@SiO_(2)@ZrO_(2),the Ce-doped sample exhibited 12%-23%increase in As(Ⅲ)uptake over p H 3-11,which was mainly attributed to the formation of bimetal M—O—As complexes.The coexisted SO^_(4)(2-)and PO^_(4)(3-)weakened As(Ⅲ)adsorption,Ca^(2+)worked oppositely,but the impact of Cl^(-)and NO_(3)^(-)was negligible.The As(Ⅲ)maximum adsorption capacity was 24.52 mg/g at 313 K with an initial As(Ⅲ)concentration of 5 mg/L at pH 7,and its kinetics was well fitted by the pseudo-second-order model.Moreover,the adsorbent exhibited remarkable recyclability.It is suggested that Fe_(3)O_(4)@SiO_(2)@Ce-ZrO_(2)is a promising adsorbent for the advanced treatment of As(Ⅲ)contaminated wastewater. 展开更多
关键词 core-shell structure magnetISM cerium doping ZIRCONIA As(Ⅲ)adsorption
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Fluorescent Superparamagnetic Core-Shell Nanostructures: Facile Synthesis of Fe@C-CN<sub>x</sub>Particles for Reusable Photocatalysts
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作者 Sankaran Murugesan Oleksandr Kuznetsov +1 位作者 Zhou Zhou Valery Khabashesku 《Advances in Nanoparticles》 2019年第1期1-19,共19页
Synthesis and characterization of hybrid fluorescent superparamagnetic core-shell particles of Fe@C-CNx composition are presented for the first time. The prepared Fe@C-CNx hybrid nanoparticles were found to possess mu... Synthesis and characterization of hybrid fluorescent superparamagnetic core-shell particles of Fe@C-CNx composition are presented for the first time. The prepared Fe@C-CNx hybrid nanoparticles were found to possess multifunctionality by exhibiting strong superparamagnetic properties and bright fluorescence emissions at 500 nm after the excitation with light in the UV-visible range. Fe@C-CNx also exhibits photocatalytic activities for organic dye degradation comparable to pure amorphous CNx with reusability through magnetic separation. The combination of magnetic and fluorescent properties of core-shell Fe@C-CNx nanoparticles opens opportunities for their application as sensors and magnet manipulated reusable photocatalysts. Superparamagnetic Fe@C core-shell nanoparticles were used as the template material in the synthesis, where the carbon shell was functionalized through one-step free-radical addition of alkyl groups terminated with carboxylic acid moieties. The method utilizes the organic acyl peroxide of dicarboxylic acid (succinic acid peroxide) as a non-oxidant functional free radical precursor for functionalization. Further, covalently functionalized succinyl-Fe@C core-shell nanoparticles were coated with the amorphous carbon nitride (CNx) generated by an in-situ solution-based chemical reaction of cyanuric chloride with lithium nitride. A detailed physicochemical characterization of the microstructure, magnetic and fluorescence properties of the synthesized hybrid nanoparticles is provided. 展开更多
关键词 magnetic Nanoparticles core-shell NANOSTRUCTURES Fe@C-CNx Fluorescence PHOTOCATALYSTS
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Recycling Fe and improving organic pollutant removal via in situ forming magnetic core-shell Fe_(3)O_(4)@CaFe-LDH in Fe(Ⅱ)-catalyzed oxidative wastewater treatment
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作者 Ting He Jie Sun +2 位作者 Liangwei Deng Jialin Ming Changwei Hu 《Journal of Environmental Sciences》 2025年第1期523-537,共15页
Due to its high efficiency,Fe(Ⅱ)-based catalytic oxidation has been one of the most popular types of technology for treating growing organic pollutants.A lot of chemical Fe sludge alongwith various refractory polluta... Due to its high efficiency,Fe(Ⅱ)-based catalytic oxidation has been one of the most popular types of technology for treating growing organic pollutants.A lot of chemical Fe sludge alongwith various refractory pollutantswas concomitantly produced,whichmay cause secondary environmental problemswithout proper disposal.We here innovatively proposed an effective method of achieving zero Fe sludge,reusing Fe resources(Fe recovery=100%)and advancing organics removal(final TOC removal>70%)simultaneously,based on the in situ formation of magnetic Ca-Fe layered double hydroxide(Fe_(3)O_(4)@CaFe-LDH)nano-material.Cations(Ca^(2+)and Fe^(3+))concentration(≥30 mmol/L)and their molar ratio(Ca:Fe≥1.75)were crucial to the success of the method.Extrinsic nano Fe_(3)O_(4)was designed to be involved in the Fe(Ⅱ)-catalytic wastewater treatment process,and was modified by oxidation intermediates/products(especially those with COO-structure),which promoted the co-precipitation of Ca^(2+)(originated from Ca(OH)_(2)added after oxidation process)and byproduced Fe^(3+)cations on its surface to in situ generate core-shell Fe_(3)O_(4)@CaFe-LDH.The oxidation products were further removed during Fe_(3)O_(4)@CaFe-LDH material formation via intercalation and adsorption.Thismethodwas applicable to many kinds of organicwastewater,such as bisphenol A,methyl orange,humics,and biogas slurry.The prepared magnetic and hierarchical CaFe-LDH nanocomposite material showed comparable application performance to the recently reported CaFe-LDHs.This work provides a new strategy for efficiently enhancing the efficiency and economy of Fe(Ⅱ)-catalyzed oxidative wastewater treatment by producing high value-added LDHs materials. 展开更多
关键词 CaFe layered double hydroxide Fe(Ⅱ)-catalytic oxidation Fe recycling magnetic nanomaterial in situ formation Fe_(3)O_(4)modification
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption
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作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 magnetic heterointerfaces Phase evolution Interfacial polarization magnetic coupling Electromagnetic wave absorption
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Advancement in utilization of magnetic resonance imaging and biomarkers in the understanding of schizophrenia
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作者 Aidan K Tirpack Danyaal G Buttar Mandeep Kaur 《World Journal of Clinical Cases》 SCIE 2025年第1期11-15,共5页
Historically,psychiatric diagnoses have been made based on patient’s reported symptoms applying the criteria from diagnostic and statistical manual of mental disorders.The utilization of neuroimaging or biomarkers to... Historically,psychiatric diagnoses have been made based on patient’s reported symptoms applying the criteria from diagnostic and statistical manual of mental disorders.The utilization of neuroimaging or biomarkers to make the diagnosis and manage psychiatric disorders remains a distant goal.There have been several studies that examine brain imaging in psychiatric disorders,but more work is needed to elucidate the complexities of the human brain.In this editorial,we examine two articles by Xu et al and Stoyanov et al,that show developments in the direction of using neuroimaging to examine the brains of people with schizo-phrenia and depression.Xu et al used magnetic resonance imaging to examine the brain structure of patients with schizophrenia,in addition to examining neurotransmitter levels as biomarkers.Stoyanov et al used functional magnetic resonance imaging to look at modulation of different neural circuits by diagnostic-specific scales in patients with schizophrenia and depression.These two studies provide crucial evidence in advancing our understanding of the brain in prevalent psychiatric disorders. 展开更多
关键词 SCHIZOPHRENIA magnetic resonance imaging Biomarkers NEUROTRANSMITTERS Psychiatric disorders
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Multiparameter magnetic resonance imaging-based radiomics model for the prediction of rectal cancer metachronous liver metastasis
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作者 Zhi-Da Long Xiao Yu +1 位作者 Zhi-Xiang Xing Rui Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期62-72,共11页
BACKGROUND The liver,as the main target organ for hematogenous metastasis of colorectal cancer,early and accurate prediction of liver metastasis is crucial for the diagnosis and treatment of patients.Herein,this study... BACKGROUND The liver,as the main target organ for hematogenous metastasis of colorectal cancer,early and accurate prediction of liver metastasis is crucial for the diagnosis and treatment of patients.Herein,this study aims to investigate the application value of a combined machine learning(ML)based model based on the multiparameter magnetic resonance imaging for prediction of rectal metachronous liver metastasis(MLM).AIM To investigate the efficacy of radiomics based on multiparametric magnetic resonance imaging images of preoperative first diagnosed rectal cancer in predicting MLM from rectal cancer.METHODS We retrospectively analyzed 301 patients with rectal cancer confirmed by surgical pathology at Jingzhou Central Hospital from January 2017 to December 2023.All participants were randomly assigned to the training or validation queue in a 7:3 ratio.We first apply generalized linear regression model(GLRM)and random forest model(RFM)algorithm to construct an MLM prediction model in the training queue,and evaluate the discriminative power of the MLM prediction model using area under curve(AUC)and decision curve analysis(DCA).Then,the robustness and generalizability of the MLM prediction model were evaluated based on the internal validation set between the validation queue groups.RESULTS Among the 301 patients included in the study,16.28%were ultimately diagnosed with MLM through pathological examination.Multivariate analysis showed that carcinoembryonic antigen,and magnetic resonance imaging radiomics were independent predictors of MLM.Then,the GLRM prediction model was developed with a comprehensive nomogram to achieve satisfactory differentiation.The prediction performance of GLRM in the training and validation queue was 0.765[95%confidence interval(CI):0.710-0.820]and 0.767(95%CI:0.712-0.822),respectively.Compared with GLRM,RFM achieved superior performance with AUC of 0.919(95%CI:0.868-0.970)and 0.901(95%CI:0.850-0.952)in the training and validation queue,respectively.The DCA indicated that the predictive ability and net profit of clinical RFM were improved.CONCLUSION By combining multiparameter magnetic resonance imaging with the effectiveness and robustness of ML-based predictive models,the proposed clinical RFM can serve as an insight tool for preoperative assessment of MLM risk stratification and provide important information for individual diagnosis and treatment of rectal cancer patients. 展开更多
关键词 Rectal cancer Metachronous liver metastases magnetic resonance imaging Radiomics Machine learning
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Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging
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作者 Holly Flyger Samantha J.Holdsworth +2 位作者 Alistair J.Gunn Laura Bennet Hamid Abbasi 《Neural Regeneration Research》 SCIE CAS 2025年第11期3144-3150,共7页
Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental disability.Detailed asse... Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental disability.Detailed assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and electroencephalography.At present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic encephalopathy.This review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent articles.This review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic accuracy.Many challenges limit the timing consistency,particularly the need for intensive care and clinical monitoring.Conversely,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after birth.This suggests that in the future it will be important to explore a wider range of times after hypoxic-ischemic encephalopathy to fully understand the optimal timing for predicting long-term outcomes. 展开更多
关键词 magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia
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Magnetic resonance imaging evaluation and nuclear receptor binding SET domain protein 1 mutation in the Sotos syndrome with attention-deficit/hyperactivity disorder
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作者 Wei Zhu 《World Journal of Clinical Cases》 SCIE 2025年第2期5-9,共5页
Sotos syndrome is characterized by overgrowth features and is caused by alterations in the nuclear receptor binding SET domain protein 1 gene.Attentiondeficit/hyperactivity disorder(ADHD)is considered a neurodevelopme... Sotos syndrome is characterized by overgrowth features and is caused by alterations in the nuclear receptor binding SET domain protein 1 gene.Attentiondeficit/hyperactivity disorder(ADHD)is considered a neurodevelopment and psychiatric disorder in childhood.Genetic characteristics and clinical presentation could play an important role in the diagnosis of Sotos syndrome and ADHD.Magnetic resonance imaging(MRI)has been used to assess medical images in Sotos syndrome and ADHD.The images process is considered to display in MRI while wavelet fusion has been used to integrate distinct images for achieving more complete information in single image in this editorial.In the future,genetic mechanisms and artificial intelligence related to medical images could be used in the clinical diagnosis of Sotos syndrome and ADHD. 展开更多
关键词 Sotos syndrome Attention-deficit/hyperactivity disorder Genetic mutation magnetic resonance imaging Wavelet fusion
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Repetitive transcranial magnetic stimulation in Alzheimer’s disease:effects on neural and synaptic rehabilitation
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作者 Yi Ji Chaoyi Yang +7 位作者 Xuerui Pang Yibing Yan Yue Wu Zhi Geng Wenjie Hu Panpan Hu Xingqi Wu Kai Wang 《Neural Regeneration Research》 SCIE CAS 2025年第2期326-342,共17页
Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and homeostasis.The Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neur... Alzheimer’s disease is a neurodegenerative disease resulting from deficits in synaptic transmission and homeostasis.The Alzheimer’s disease brain tends to be hyperexcitable and hypersynchronized,thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life,leaving patients incapacitated.Repetitive transcranial magnetic stimulation is a cost-effective,neuro-modulatory technique used for multiple neurological conditions.Over the past two decades,it has been widely used to predict cognitive decline;identify pathophysiological markers;promote neuroplasticity;and assess brain excitability,plasticity,and connectivity.It has also been applied to patients with dementia,because it can yield facilitatory effects on cognition and promote brain recovery after a neurological insult.However,its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of studies.This study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment,evaluate its effects on synaptic plasticity,and identify the associated mechanisms.This review essentially focuses on changes in the pathology,amyloidogenesis,and clearance pathways,given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer’s disease.Apoptotic mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription,which are closely related to the neural regeneration process,are also highlighted.Finally,we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation,with the aim to highlight future directions for better clinical translations. 展开更多
关键词 Alzheimer’s disease amyloid deposition apoptotic mechanisms BIOMARKER neural regeneration NEURODEGENERATION repetitive transcranial magnetic stimulation synaptic plasticity
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Semantic Segmentation of Lumbar Vertebrae Using Meijering U-Net(MU-Net)on Spine Magnetic Resonance Images
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作者 Lakshmi S V V Shiloah Elizabeth Darmanayagam Sunil Retmin Raj Cyril 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期733-757,共25页
Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people everywhere.Due to its ability to produce a detailed view of the soft tissues,including the s... Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people everywhere.Due 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 spine.The semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar diseases.It 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 accuracy.This 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 S1.Pseudo-colour mask images were generated and used as ground truth for training the model.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 Data.The 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. 展开更多
关键词 Computer aided diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar vertebrae deep learning U-Net model
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Synthesis,structure,and magnetic property of a cobalt(Ⅱ)complex based on pyridyl⁃substituted imino nitroxide radical
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作者 WANG Xiaoling ZHANG Hongwu LIU Daofu 《无机化学学报》 北大核心 2025年第2期407-412,共6页
A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,el... A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,elemental analysis,IR,and magnetic properties.X-ray diffraction analysis shows that the complex exists as mononuclear molecules and Co(Ⅱ)ion is four-coordinated with two radicals and two PNB-ligands.The magnetic susceptibility study indicates the complex exhibits weak ferromagnetic interactions between cobalt(Ⅱ)and im4-py radical.The magnetic property is explained by the magnetic and structure exchange mechanism.CCDC:976028. 展开更多
关键词 Co(Ⅱ)complex imino nitroxide radical crystal structure magnetic property
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Generation of 10 kT axial magnetic fields using multiple conventional laser beams:A sensitivity study for kJ PW-class laser facilities
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作者 Jue Xuan Hao Xiang Tang +4 位作者 Alexey Arefiev Robert J.Kingham Ping Zhu Yin Shi Jian Zheng 《Matter and Radiation at Extremes》 2025年第1期15-32,共18页
Strong multi-kilotesla magnetic fields have various applications in high-energy density science and laboratory astrophysics,but they are not readily available.In our previous work[Y.Shi et al.,Phys.Rev.Lett.130,155101... Strong multi-kilotesla magnetic fields have various applications in high-energy density science and laboratory astrophysics,but they are not readily available.In our previous work[Y.Shi et al.,Phys.Rev.Lett.130,155101(2023)],we developed a novel approach for generating such fields using multiple conventional laser beams with a twist in the pointing direction.This method is particularly well-suited for multi-kilojoule petawatt-class laser systems like SG-II UP,which are designed with multiple linearly polarized beamlets.Utilizing three-dimensional kinetic particle-in-cell simulations,we examine critical factors for a proof-of-principle experiment,such as laser polarization,relative pulse delay,phase offset,pointing stability,and target configuration,and their impact on magnetic field generation.Our general conclusion is that the approach is very robust and can be realized under a wide range of laser parameters and plasma conditions.We also provide an in-depth analysis of the axial magnetic field configuration,azimuthal electron current,and electron and ion orbital angular momentum densities.Supported by a simple model,our analysis shows that the axial magnetic field decays owing to the expansion of hot electrons. 展开更多
关键词 POLARIZATION magnetic AXIAL
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High-grade pancreatic intraepithelial neoplasia: A commentary of magnetic resonance cholangiopancreatography findings
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作者 Alessandro Posa Enza Genco 《World Journal of Clinical Cases》 2025年第11期72-74,共3页
Commentary on the role of magnetic resonance cholangiopancreatography fin-dings in diagnosing high grade pancreatic intraepithelial neoplasms.
关键词 magnetic resonance CHOLANGIOPANCREATOGRAPHY PANCREAS Intraepithelial neoplasms Diagnosis
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Magnetic Induction Communication in Extreme Environments:Principles,Technologies,and Challenges
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作者 Jiang Tao Zhang Yixin Liu Guanghua 《China Communications》 2025年第1期256-264,共9页
Wireless communications in extreme environments,such as underwater and underground,is an essential technology for interconnecting various devices and enables data transmission and networking.Existing wireless technolo... Wireless communications in extreme environments,such as underwater and underground,is an essential technology for interconnecting various devices and enables data transmission and networking.Existing wireless technologies using electromagnetic(EM)waves face many known problems,such as high path loss,unpredictable multi-path fading,and large antenna size in the lossy medium.In this article,the magnetic induction(MI)based physical layer communication is introduced as a promising solution for wireless transmissions in extreme environments.Specifically,the fundamentals of the MI-based communications are reviewed.Then,with the goal of establishing reliable and low-power links between small-size devices,we review several key physical layer technologies for MI-based communications,including the MIbased signal modulations,magnetic beamforming,and relay transmissions,and summarize their state-of-theart research advances.Finally,the related open issues and challenges in each area are analyzed and presented for future investigations. 展开更多
关键词 BEAMFORMING magnetic induction communications relay transmission signal modulation
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High-resolution direct magnetic resonance imaging fistulography with hydrogen peroxide for diagnosing anorectal fistula: A preliminary retrospective study
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作者 Can-Can Chang Long-Hu Qiao +5 位作者 Zhen-Qi Zhang Xiao Tian Yu Zhang Wen-Wen Cheng Xia Wang Qing Yang 《World Journal of Radiology》 2025年第1期32-40,共9页
BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)i... BACKGROUND Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin.Multiple imagining methods are available to evaluate it,among which magnetic resonance imaging(MRI)is the most advanced nonin-vasive preoperative method.However,it is limited in its visualization function.AIM To investigate the use of intraluminal MRI for perianal fistulas via a novel direct MRI fistulography method.METHODS We mixed 3%hydrogen peroxide(HP)with gadolinium for HPMRI fistulogra-phy,retrospectively analyzing 60 cases of complex/recurrent fistula-in-ano using physical examination,trans-perineal ultrasonography(TPUS),low-spatial-reso-lution MRI,and high-resolution direct HPMRI fistulography.We assessed detec-tion rates of fistula tracks,internal openings,their relationship with anal sphinc-ters,and perianal abscesses using statistical analyses,including interobserver agreement(Kappa statistic),and compared results with intraoperative findings.RESULTS Surgical confirmation in 60 cases showed that high-resolution direct HPMRI fis-tulography provided superior detection rates for internal openings(153)and fistula tracks(162)compared to physical exams,TPUS,and low-spatial-resolution MRI(Z>5.7,P<0.05).The effectiveness of physical examination and TPUS was also inferior to that of our method for detecting perianal abscesses(54)(Z=6.773,3.694,P<0.05),whereas that of low-spatial-resolution MRI was not significantly different(Z=1.851,P=0.06).High-resolution direct HPMRI fistulography also achieved the highest interobserver agreement(Kappa:0.89,0.85,and 0.80),while low-spatial-resolution MRI showed moderate agreement(Kappa:0.78,0.74,and 0.69).TPUS and physical examination had lower agreement(Kappa range:0.33-0.63).CONCLUSION High-resolution direct HPMRI fistulography enhances the visualization of recurrent and complex fistula-in-ano,including branched fistulas,allowing for precise planning and improved surgical outcomes. 展开更多
关键词 Key fistula-in-ano magnetic resonance imaging Hydrogen peroxide Perianal abscess Fistulography
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Predictive value of magnetic resonance imaging parameters combined with tumor markers for rectal cancer recurrence risk after surgery
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作者 Lei Wu Jing-Jie Zhu +2 位作者 Xiao-Han Liang He Tong Yan Song 《World Journal of Gastrointestinal Surgery》 2025年第2期161-172,共12页
BACKGROUND An increasing number of studies to date have found preoperative magnetic resonance imaging(MRI)features valuable in predicting the prognosis of rectal cancer(RC).However,research is still lacking on the cor... BACKGROUND An increasing number of studies to date have found preoperative magnetic resonance imaging(MRI)features valuable in predicting the prognosis of rectal cancer(RC).However,research is still lacking on the correlation between preoperative MRI features and the risk of recurrence after radical resection of RC,urgently necessitating further in-depth exploration.AIM To investigate the correlation between preoperative MRI parameters and the risk of recurrence after radical resection of RC to provide an effective tool for predicting postoperative recurrence.METHODS The data of 90 patients who were diagnosed with RC by surgical pathology and underwent radical surgical resection at the Second Affiliated Hospital of Bengbu Medical University between May 2020 and December 2023 were collected through retrospective analysis.General demographic data,MRI data,and tumor markers levels were collected.According to the reviewed data of patients six months after surgery,the clinicians comprehensively assessed the recurrence risk and divided the patients into high recurrence risk(37 cases)and low recurrence risk(53 cases)groups.Independent sample t-test andχ2 test were used to analyze differences between the two groups.A logistic regression model was used to explore the risk factors of the high recurrence risk group,and a clinical prediction model was constructed.The clinical prediction model is presented in the form of a nomogram.The receiver operating characteristic curve,Hosmer-Lemeshow goodness of fit test,calibration curve,and decision curve analysis were used to evaluate the efficacy of the clinical prediction model.RESULTS The detection of positive extramural vascular invasion through preoperative MRI[odds ratio(OR)=4.29,P=0.045],along with elevated carcinoembryonic antigen(OR=1.08,P=0.041),carbohydrate antigen 125(OR=1.19,P=0.034),and carbohydrate antigen 199(OR=1.27,P<0.001)levels,are independent risk factors for increased postoperative recurrence risk in patients with RC.Furthermore,there was a correlation between magnetic resonance based T staging,magnetic resonance based N staging,and circumferential resection margin results determined by MRI and the postoperative recurrence risk.Additionally,when extramural vascular invasion was integrated with tumor markers,the resulting clinical prediction model more effectively identified patients at high risk for postoperative recurrence,thereby providing robust support for clinical decision-making.CONCLUSION The results of this study indicate that preoperative MRI detection is of great importance for predicting the risk of postoperative recurrence in patients with RC.Monitoring these markers helps clinicians identify patients at high risk,allowing for more aggressive treatment and monitoring strategies to improve patient outcomes. 展开更多
关键词 Rectal cancer magnetic resonance imaging RECURRENCE Prediction model Tumor markers
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Toroidal torques due to n=1 magnetic perturbations in ITER baseline scenario
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作者 Jingwei LI Li LI +5 位作者 Yueqiang LIU Yunfeng LIANG Yanfei WANG Lu TIAN Zhongqing LIU Fangchuan ZHONG 《Plasma Science and Technology》 2025年第1期39-51,共13页
Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),i... Toroidal torques,generated by the resonant magnetic perturbation(RMP)and acting on the plasma column,are numerically systematically investigated for an ITER baseline scenario.The neoclassical toroidal viscosity(NTV),in particular the resonant portion,is found to provide the dominant contribution to the total toroidal torque under the slow plasma flow regime in ITER.While the electromagnetic torque always opposes the plasma flow,the toroidal torque associated with the Reynolds stress enhances the plasma flow independent of the flow direction.A peculiar double-peak structure for the net NTV torque is robustly computed for ITER,as the toroidal rotation frequency is scanned near the zero value.This structure is found to be ultimately due to a non-monotonic behavior of the wave-particle resonance integral(over the particle pitch angle)in the superbanana plateau NTV regime in ITER.These findings are qualitatively insensitive to variations of a range of factors including the wall resistivity,the plasma pedestal flow and the assumed frequency of the rotating RMP field. 展开更多
关键词 toroidal torques resonant magnetic perturbation fieds plasma flow ITER baseline scenario
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