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Analysis method of chaos and sub-harmonic resonance of nonlinear system without small parameters
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作者 刘延彬 陈予恕 曹庆杰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第1期1-10,共10页
The Melnikov method is important for detecting the presence of transverse homoclinic orbits and the occurrence of homoclinic bifurcations. Unfortunately, the traditional Melnikov methods strongly depend on small param... The Melnikov method is important for detecting the presence of transverse homoclinic orbits and the occurrence of homoclinic bifurcations. Unfortunately, the traditional Melnikov methods strongly depend on small parameters, which do not exist in most practical systems. Those methods are limited in dealing with the systems with strong nonlinearities. This paper presents a procedure to study the chaos and sub-harmonic resonance of strongly nonlinear practical systems by employing a homotopy method that is used to extend the Melnikov functions to the strongly nonlinear systems. Applied to a given example, the procedure shows the effectiveness via the comparison of the theoretical results and the numerical simulation. 展开更多
关键词 homotopy analysis Melnikov function CHAOS sub-harmonic resonance
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Sub-Harmonic Resonances of Periodic Parameter Excited Oscillators with Discontinuities
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作者 Jifeng Cui 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第4期66-71,共6页
It is difficult to obtain analytic approximations of nonlinear problems such as parameter excited system with strong nonlinearity. An analytic approach based on the homotopy analysis method( HAM) is proposed to study ... It is difficult to obtain analytic approximations of nonlinear problems such as parameter excited system with strong nonlinearity. An analytic approach based on the homotopy analysis method( HAM) is proposed to study the sub-harmonic resonances of highly nonlinear parameter excited oscillating systems with absolute value terms. The non-smoothness of absolute value terms is handled by means of an iteration approach with Fourier expansion. Two typical examples are employed to illustrate the validity and flexibility of this approach. The square residuals of the homotopy-approximations of the two examples decrease to 10-6and 10-5,respectively. Thus,the HAM combining with other methods gives hope to solve complex singular oscillating systems analytically. 展开更多
关键词 periodic parameter excited oscillator sub-harmonic resonance HAM Fourier expansion
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Analysis of 1/2 sub-harmonic resonance in a maneuvering rotor system 被引量:11
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作者 HOU Lei CHEN YuShu 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第1期203-209,共7页
This paper focuses on the 1/2 sub-harmonic resonance of an aircraft’s rotor system under hovering flight that can be modeled as a maneuver load G in the equations of motion.The effect on the rotor system is analyzed ... This paper focuses on the 1/2 sub-harmonic resonance of an aircraft’s rotor system under hovering flight that can be modeled as a maneuver load G in the equations of motion.The effect on the rotor system is analyzed by using theoretical methods.It is shown that the sub-harmonic resonance may occur due to maneuvering flight conditions.The larger the eccentricity E and the maneuver load G,the greater the sub-harmonic resonance.The effects of nonlinear stiffness,damping of the system,maneuver load,and eccentricity on the sub-harmonic resonance region in parameter planes are also investigated.Bifurcation diagrams of the analytical solutions are in good agreement with that of the numerical simulation solutions.These results will contribute to the understanding of the nonlinear dynamic behaviors of maneuvering rotor systems. 展开更多
关键词 sub-harmonic resonance maneuvering rotor system hovering flight maneuver load
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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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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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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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Incidental Finding of Deep Vein Thrombosis on Routine Knee Magnetic Resonance Imaging
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作者 Karoline Kant Michael Facek Craig Buchan 《iRADIOLOGY》 2025年第1期88-89,共2页
A 53 year old male presented to his local doctor with an acute knee injury,limited knee movement and a haemoarthrosis.Patient did not have calf tenderness or clinical suspicion for deep vein thrombosis(DVT).He was ref... A 53 year old male presented to his local doctor with an acute knee injury,limited knee movement and a haemoarthrosis.Patient did not have calf tenderness or clinical suspicion for deep vein thrombosis(DVT).He was referred for a routine acute knee magnetic resonance imaging(MRI)scan.This MRI demonstrated a full thickness anterior cruciate ligament tear with additional findings,of a probable incidental DVT.The relevant MRI findings suggestive of DVT in this case included perivascular edema and expanded caliber of the involved medial gastronomical veins on the axial proton density fat suppressed sequence(Figure 1). 展开更多
关键词 deep vein thrombosis magnetic resonance ULTRASOUND
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Characteristics of radio-frequency magnetron sputtering with Ag target operated near the electron series resonance oscillation
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作者 Chao YE 《Plasma Science and Technology》 2025年第3期111-117,共7页
The discharge and plasma characteristics of Ag magnetron sputtering discharge operated near the electron series resonance(ESR)oscillation,which was excited using the driving frequency of 27.12 MHz,was investigated.The... The discharge and plasma characteristics of Ag magnetron sputtering discharge operated near the electron series resonance(ESR)oscillation,which was excited using the driving frequency of 27.12 MHz,was investigated.The imaginary part of impedance was found to undergo a transition from capacitive to inductive on varying radio-frequency(RF)power,and the conditions for the ESR excitation were satisfied.The current–voltage(I–V)characteristic of discharge showed that the lower discharge voltage with higher current was an important feature of RF magnetron sputtering operated near the ESR oscillation,which was caused by the small impedance Z originated from the mutual compensation between the sheath capacitive reactance and the plasma inductive reactance.The higher electron temperature,ion flux density and ion energy as well as the moderate electron density were obtained.The interaction of higher energy ions on substrate surface improved the crystallographic quality of Ag films.Therefore,the 27.12 MHz magnetron sputtering operated near the ESR oscillation has better deposition characteristics than that of commercial 13.56 MHz RF magnetron sputtering. 展开更多
关键词 electron series resonance magnetron sputtering radio-frequency discharge
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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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Observation of momentum-induced broadening of width in narrow Feshbach resonances of ultracold ^(133)Cs atoms
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作者 Zhennan Liu Hongxing Zhao +8 位作者 Yunfei Wang Yuqing Li Jizhou Wu Wenliang Liu Peng Li Yongming Fu Liantuan Xiao Jie Ma Suotang Jia 《Chinese Physics B》 2025年第2期257-260,共4页
Interactions between atoms in ultracold quantum gases play an important role in the study of the quantum simulation of many-body physics.Feshbach resonance is a versatile tool to control atomic interactions,where the ... Interactions between atoms in ultracold quantum gases play an important role in the study of the quantum simulation of many-body physics.Feshbach resonance is a versatile tool to control atomic interactions,where the atom-loss spectra are widely used to characterize Feshbach resonances of various atomic species.Here,we report the experimental observation of momentum-induced broadening of widths in atom-loss spectra of narrow ^(133)Cs Feshbach resonances.We drive Bragg excitation to kick the Bose-Einstein condensate of Cs atoms in a cigar-shaped optical trap,and measure the atom-loss spectra of narrow Feshbach resonances of moving ultracold atoms near the magnetic fields 19.84 G and 47.97 G.We show that the widths of the atom-loss spectra are broadened for the atoms with the momenta of 2hk,and 4hk,and even observe splitting in the Feshbach resonance of the atoms with momentum 4hk.Our work may open the way for exploring the interesting physical phenomena arising from the collective velocity of colliding atoms that have been ignored in general. 展开更多
关键词 Bose–Einstein condensate Feshbach resonances atom-loss spectra
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Semi-supervised cardiac magnetic resonance image segmentation based on domain generalization
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作者 SHAO Hong HOU Jinyang CUI Wencheng 《High Technology Letters》 2025年第1期41-52,共12页
In the realm of medical image segmentation,particularly in cardiac magnetic resonance imaging(MRI),achieving robust performance with limited annotated data is a significant challenge.Performance often degrades when fa... In the realm of medical image segmentation,particularly in cardiac magnetic resonance imaging(MRI),achieving robust performance with limited annotated data is a significant challenge.Performance often degrades when faced with testing scenarios from unknown domains.To address this problem,this paper proposes a novel semi-supervised approach for cardiac magnetic resonance image segmentation,aiming to enhance predictive capabilities and domain generalization(DG).This paper establishes an MT-like model utilizing pseudo-labeling and consistency regularization from semi-supervised learning,and integrates uncertainty estimation to improve the accuracy of pseudo-labels.Additionally,to tackle the challenge of domain generalization,a data manipulation strategy is introduced,extracting spatial and content-related information from images across different domains,enriching the dataset with a multi-domain perspective.This papers method is meticulously evaluated on the publicly available cardiac magnetic resonance imaging dataset M&Ms,validating its effectiveness.Comparative analyses against various methods highlight the out-standing performance of this papers approach,demonstrating its capability to segment cardiac magnetic resonance images in previously unseen domains even with limited annotated data. 展开更多
关键词 SEMI-SUPERVISED domain generalization(DG) cardiac magnetic resonance image segmentation
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Role of WARP sequence magnetic resonance imaging with the removal of metal artifacts in the evaluation of lumbar adjacent
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作者 Wei Xu Meng-Yun Xiong +4 位作者 Yi Wang Qi-Feng Yu Xiao-Jian Ye Si-Lian Wang Zhi-Kun Li 《World Journal of Orthopedics》 2025年第3期56-64,共9页
BACKGROUND Posterior lumbar interbody fusion has good clinical results,but adjacent segment disease(ASD)affects its long-term efficacy.In patients with L4-5 fusion who were followed up for more than 10 years,the ASD i... BACKGROUND Posterior lumbar interbody fusion has good clinical results,but adjacent segment disease(ASD)affects its long-term efficacy.In patients with L4-5 fusion who were followed up for more than 10 years,the ASD incidence was 33.3%.Magnetic resonance imaging(MRI)is key for ASD diagnosis,but metal artifacts from internal fixation limit its use;therefore,removing the artifacts is crucial for ASD diagnosis and treatment.AIM To evaluate the value of WARP MRI for patients with lumbar ASD.METHODS In our hospital,the lumbar spines of patients with ASD were assessed via lumbar MRI,including conventional sequences and sequences for artifacts.A PACS workstation was used for image measurement,analysis,and assessment,which mainly included measurement of the internal fixation implant artifact area,evaluation of the visibility of the anatomical structures surrounding the implant,and diagnostic assessment of ASD in the section.Conventional MRI data sequences and artifacts to sequence the contrast analysis of the MRI data.RESULTS A total of 30 patients with ASD after lumbar fusion and internal fixation were included in the study;the patients included 13 male and 17 female patients and were aged 66.03±5.83 years.The metal artifact area of the WARP T2-tirm sequence was significantly smaller than that of the conventional STIR sequence[(20.85±6.27)cm²vs(50.56±8.55)cm²,P<0.01].The WARP T2-tirm sequence was observed around the implants,pedicles,intervertebral foramen,and vertebral bodies,and the conventional STIR sequence clearly displayed nerve roots within the intervertebral foramen.In all 30 patients,all adjacent segments of the WARP T2-tirm sequence could be clearly observed(above Grade 4),whereas it was difficult to observe these segments in the conventional STIR sequence due to the presence of more severe metal artifacts.CONCLUSION WARP sequences can significantly reduce the artifact area in the sagittal and cross-sectional images of titanium alloy spinal fixation,providing a good imaging reference for the diagnosis of ASD. 展开更多
关键词 Adjacent segment disease Metal artifact Metal artifact Magnetic resonance
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Renal angiomyolipomas:Typical and atypical features on computed tomography and magnetic resonance imaging
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作者 Andres Labra Giancarlo Schiappacasse +1 位作者 Diego Constenla Joaquin Cristi 《World Journal of Radiology》 2025年第2期11-20,共10页
Angiomyolipomas(AMLs)represent the most common benign solid renal tumors.The frequency of their detection in the general population is increasing owing to advances in imaging technology.The objective of this review is... Angiomyolipomas(AMLs)represent the most common benign solid renal tumors.The frequency of their detection in the general population is increasing owing to advances in imaging technology.The objective of this review is to discuss computed tomography(CT)and magnetic resonance imaging findings for both typical and atypical renal AMLs,along with their associated complications.AMLs are typically defined as solid triphasic tumors composed of varying amounts of dysmorphic and tortuous blood vessels,smooth muscle components and adipose tissue.In an adult,a classical renal AML appears as a solid,heterogeneous renal cortical mass with macroscopic fat.However,up to 5%of AMLs contain minimal fat and cannot be reliably diagnosed by imaging.Fat-poor AMLs can appear as hyperattenuating masses on unenhanced CT and as hypointense masses on T2WI;other AMLs may be isodense or exhibit cystic components.Hemorrhage is the most common complication,and AMLs with hemorrhage can mimic other tumors,making their diagnosis challenging.Understanding the variable and heterogeneous nature of this neoplasm to correctly classify renal AMLs and to avoid misdiagnosis of other renal lesions is crucial. 展开更多
关键词 Kidney neoplasms ANGIOMYOLIPOMA Classic angiomyolipoma-fat poor angiomyolipoma Tomography X-ray computed Magnetic resonance imaging
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Magnetic resonance imaging bias field correction improves tumor prognostic evaluation after transcatheter arterial chemoembolization for liver cancer
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作者 Ke Liu Jun-Biao Li +1 位作者 Yong Wang Yan Li 《World Journal of Gastrointestinal Surgery》 2025年第4期207-220,共14页
BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evalu... BACKGROUND Transcatheter arterial chemoembolization(TACE)is a key treatment approach for advanced invasive liver cancer(infiltrative hepatocellular carcinoma).However,its therapeutic response can be difficult to evaluate accurately using conventional two-dimensional imaging criteria due to the tumor’s diffuse and multifocal growth pattern.Volumetric imaging,especially enhanced tumor volume(ETV),offers a more comprehensive assessment.Nonetheless,bias field inhomogeneity in magnetic resonance imaging(MRI)poses challenges,potentially skewing volumetric measurements and undermining prognostic evaluation.AIM To investigate whether MRI bias field correction enhances the accuracy of volumetric assessment of infiltrative hepatocellular carcinoma treated with TACE,and to analyze how this improved measurement impacts prognostic prediction.METHODS We retrospectively collected data from 105 patients with invasive liver cancer who underwent TACE treatment at the Affiliated Hospital of Xuzhou Medical University from January 2020 to January 2024.The improved N4 bias field correction algorithm was applied to process MRI images,and the ETV before and after treatment was calculated.The ETV measurements before and after correction were compared,and their relationship with patient prognosis was analyzed.A Cox proportional hazards model was used to evaluate prognostic factors,with Martingale residual analysis determining the optimal cutoff value,followed by survival analysis.RESULTS Bias field correction significantly affected ETV measurements,with the corrected baseline ETV mean(505.235 cm³)being significantly lower than before correction(825.632 cm³,P<0.001).Cox analysis showed that the hazard ratio(HR)for corrected baseline ETV(HR=1.165,95%CI:1.069-1.268)was higher than before correction(HR=1.063,95%CI:1.031-1.095).Using 412 cm³as the cutoff,the group with baseline ETV<415 cm³had a longer median survival time compared to the≥415 cm³group(18.523 months vs 8.926 months,P<0.001).The group with an ETV reduction rate≥41%had better prognosis than the<41%group(17.862 months vs 9.235 months,P=0.006).Multivariate analysis confirmed that ETV reduction rate(HR=0.412,P<0.001),Child-Pugh classification(HR=0.298,P<0.001),and Barcelona Clinic Liver Cancer stage(HR=0.578,P=0.045)were independent prognostic factors.CONCLUSION Volume imaging based on MRI bias field correction can improve the accuracy of evaluating the efficacy of TACE treatment for invasive liver cancer.The corrected ETV and its reduction rate can serve as independent indicators for predicting patient prognosis,providing important reference for developing individualized treatment strategies. 展开更多
关键词 Invasive liver cancer Transcatheter arterial chemoembolization Magnetic resonance imaging Bias field correction Volume imaging
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Cloud-magnetic resonance imaging system:In the era of 6G and artificial intelligence
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作者 Yirong Zhou Yanhuang Wu +6 位作者 Yuhan Su Jing Li Jianyu Cai Yongfu You Jianjun Zhou Di Guo Xiaobo Qu 《Magnetic Resonance Letters》 2025年第1期52-63,共12页
Magnetic resonance imaging(MRI)plays an important role in medical diagnosis,generating petabytes of image data annually in large hospitals.This voluminous data stream requires a significant amount of network bandwidth... Magnetic resonance imaging(MRI)plays an important role in medical diagnosis,generating petabytes of image data annually in large hospitals.This voluminous data stream requires a significant amount of network bandwidth and extensive storage infrastructure.Additionally,local data processing demands substantial manpower and hardware investments.Data isolation across different healthcare institutions hinders crossinstitutional collaboration in clinics and research.In this work,we anticipate an innovative MRI system and its four generations that integrate emerging distributed cloud computing,6G bandwidth,edge computing,federated learning,and blockchain technology.This system is called Cloud-MRI,aiming at solving the problems of MRI data storage security,transmission speed,artificial intelligence(AI)algorithm maintenance,hardware upgrading,and collaborative work.The workflow commences with the transformation of k-space raw data into the standardized Imaging Society for Magnetic Resonance in Medicine Raw Data(ISMRMRD)format.Then,the data are uploaded to the cloud or edge nodes for fast image reconstruction,neural network training,and automatic analysis.Then,the outcomes are seamlessly transmitted to clinics or research institutes for diagnosis and other services.The Cloud-MRI system will save the raw imaging data,reduce the risk of data loss,facilitate inter-institutional medical collaboration,and finally improve diagnostic accuracy and work efficiency. 展开更多
关键词 Magnetic resonance imaging Cloud computing 6G bandwidth Artificial intelligence Edge computing Federated learning Blockchain
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Resonance analysis of^(159)Tb(n,γ)reaction based on the CSNS Back-n experiment
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作者 De-Xin Wang Su-Ya-La-Tu Zhang +14 位作者 Wei Jiang Jie Ren Mei-Rong Huang Jing-Yu Tang Xi-Chao Ruan Hong-Wei Wang Long-Xiang Liu Xue Li Dan-Dan Niu Guo Li Gu-Fu Meng Yong-Shun Huang Zhi-Long Wang Yu Bai Xue Yang 《Nuclear Science and Techniques》 2025年第3期85-94,共10页
The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were... The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were performed for the neutron capture cross sections of 159Tb measured at the China Spallation Neutron Source(CSNS)backscattering white neutron beamline(Back-n)facility.The resonance parameters were extracted from the R-Matrix code SAMMY and fitted to the experimental capture yield up to the 1.2 keV resolved resonance region(RRR).The average resonance parameters were determined by performing statistical analysis on the set of the resonance parameters in the RRR.These results were used to fit the measured average capture cross sections using the FITACS code in the unresolved resonance region from 2 keV to 1 MeV.The contributions of partial waves l=0,1,2 to the average capture cross sections are reported. 展开更多
关键词 Statistical analysis resonance parameters ^(159)Tb(n γ)cross section γ
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Enhancing lymphoma staging: Unveiling the potential and challenges of whole-body magnetic resonance imaging
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作者 Mohadese Ahmadzade Mohammad Ghasemi-Rad 《World Journal of Radiology》 2025年第3期1-4,共4页
In this editorial,we comment on the article by Lambert et al,published in the recent issue of the World Journal of Radiology.The focus of the editorial is to explore the advancements in whole-body magnetic resonance i... In this editorial,we comment on the article by Lambert et al,published in the recent issue of the World Journal of Radiology.The focus of the editorial is to explore the advancements in whole-body magnetic resonance imaging(WB-MRI)techno-logy,its current clinical applications,and the challenges that must be addressed to fully realize its potential in oncological imaging.WB-MRI has emerged as a pivotal tool in oncological imaging,offering comprehensive disease assessment without ionizing radiation.Its applications span the detection of bone metastases,evaluation of hematologic malignancies,and staging of a wide range of cancers,including lymphoma,prostate,and breast cancers.Advanced techniques such as diffusion-weighted imaging have enhanced its diagnostic performance by pro-viding superior lesion-to-background contrast and quantitative metrics.Despite its diagnostic strengths,WB-MRI faces challenges in standardization,patient acceptance,and integration into clinical workflows.Variability in acquisition pro-tocols,hardware differences,and patient-related factors,such as anxiety and motion artifacts,have limited widespread adoption.Emerging guidelines like MET-RADS-P and ONCO-RADS aim to address these issues by promoting stan-dardized protocols tailored to specific clinical needs.This editorial explores the advancements in WB-MRI technology,its current clinical applications,and the barriers that must be overcome to maximize its utility.By addressing these cha-llenges and embracing standardization,WB-MRI holds the potential to redefine the landscape of oncological imaging,aligning diagnostic precision with modern treatment goals of reducing long-term patient risk. 展开更多
关键词 Whole-body magnetic resonance imaging Diffusion-weighted imaging Lymphoma staging Oncological imaging Diagnostic performance Cancer screening Tumor burden assessment
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