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Attention U-Net for Precision Skeletal Segmentation in Chest X-Ray Imaging:Advancing Person Identification Techniques in Forensic Science
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作者 Hazem Farah Akram Bennour +3 位作者 Hama Soltani Mouaaz Nahas Rashiq Rafiq Marie Mohammed Al-Sarem 《Computers, Materials & Continua》 2025年第11期3335-3348,共14页
This study presents an advanced method for post-mortem person identification using the segmentation of skeletal structures from chest X-ray images.The proposed approach employs the Attention U-Net architecture,enhance... This study presents an advanced method for post-mortem person identification using the segmentation of skeletal structures from chest X-ray images.The proposed approach employs the Attention U-Net architecture,enhanced with gated attention mechanisms,to refine segmentation by emphasizing spatially relevant anatomical features while suppressing irrelevant details.By isolating skeletal structures which remain stable over time compared to soft tissues,this method leverages bones as reliable biometric markers for identity verification.The model integrates custom-designed encoder and decoder blocks with attention gates,achieving high segmentation precision.To evaluate the impact of architectural choices,we conducted an ablation study comparing Attention U-Net with and without attentionmechanisms,alongside an analysis of data augmentation effects.Training and evaluation were performed on a curated chest X-ray dataset,with segmentation performance measured using Dice score,precision,and loss functions,achieving over 98% precision and 94% Dice score.The extracted bone structures were further processed to derive unique biometric patterns,enabling robust and privacy-preserving person identification.Our findings highlight the effectiveness of attentionmechanisms in improving segmentation accuracy and underscore the potential of chest bonebased biometrics in forensic and medical imaging.This work paves the way for integrating artificial intelligence into real-world forensic workflows,offering a non-invasive and reliable solution for post-mortem identification. 展开更多
关键词 Bone extraction segmentation of skeletal structures chest x-ray images person identification deep learning attention mechanisms U-Net
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Multimodal imaging techniques for the diagnosis of congenital left renal arteriovenous fistula:A case report
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作者 Shui-Ping Lv Li-Li Qin +2 位作者 Huan Mou Teng Huang Kai-Quan Wang 《World Journal of Clinical Cases》 2025年第21期84-92,共9页
BACKGROUND Congenital renal arteriovenous fistula(RAVF)is a clinically rare condition and frequently missed and misdiagnosed.Multimodal imaging techniques can pro-vide more detailed diagnostic information to help phys... BACKGROUND Congenital renal arteriovenous fistula(RAVF)is a clinically rare condition and frequently missed and misdiagnosed.Multimodal imaging techniques can pro-vide more detailed diagnostic information to help physicians more accurately diagnose and treat diseases.Combining imaging methods to diagnose RAVF has rarely been reported.CASE SUMMARY A 69-year-old female patient presented with gross hematuria that had persisted for 10 days.The patient underwent ultrasound examinations of the kidneys and renal blood vessels,enhanced computed tomography,three-dimensional com-puted tomography angiography,and digital subtraction angiography of the renal arteries.These revealed dilatation of the left renal vein and abnormal shunting between the left renal artery and vein.The patient was diagnosed with a left RAVF using combined multimodal imaging techniques.The patient was treated with left renal artery embolization immediately after renal arteriography.Hema-turia resolved following the left renal artery embolization without serious bleeding or other complications.The patient made a full recovery after one year of postoperative follow-up.CONCLUSION Multimodal imaging techniques complement each other when diagnosing RAVF,providing detailed diagnostic information that can aid in accurate diagnosis and treatment.In addition,this case reminds the sonographer to pay more attention to the color doppler flow imaging and blood flow spectrum when examining the kidney,so as to avoid misdiagnosis of renal cystic lesions as renal cysts and missed diagnosis of RAVF. 展开更多
关键词 Renal arteriovenous fistula Multimodal imaging techniques Color doppler ultrasound DIAGNOSIS Case report
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Synaptic pruning mechanisms and application of emerging imaging techniques in neurological disorders
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作者 Yakang Xing Yi Mo +1 位作者 Qihui Chen Xiao Li 《Neural Regeneration Research》 2026年第5期1698-1714,共17页
Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience... Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders. 展开更多
关键词 CHEMOKINE COMPLEMENT experience-dependent driven synaptic pruning imaging techniques NEUROGLIA signaling pathways synapse elimination synaptic pruning
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Tests of Solar X-Ray Image Reconstruction:Study of X-Ray Imaging Algorithms and Reconstruction Parameters 被引量:1
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作者 Wenhui Yu Yang Su +2 位作者 Zhentong Li Wei Chen Weiqun Gan 《Research in Astronomy and Astrophysics》 2025年第3期90-110,共21页
Imaging observations of solar X-ray bursts can reveal details of the energy release process and particle acceleration in flares.Most hard X-ray imagers make use of the modulation-based Fourier transform imaging method... Imaging observations of solar X-ray bursts can reveal details of the energy release process and particle acceleration in flares.Most hard X-ray imagers make use of the modulation-based Fourier transform imaging method,an indirect imaging technique that requires algorithms to reconstruct and optimize images.During the last decade,a variety of algorithms have been developed and improved.However,it is difficult to quantitatively evaluate the image quality of different solutions without a true,reference image of observation.How to choose the values of imaging parameters for these algorithms to get the best performance is also an open question.In this study,we present a detailed test of the characteristics of these algorithms,imaging dynamic range and a crucial parameter for the CLEAN method,clean beam width factor(CBWF).We first used SDO/AIA EUV images to compute DEM maps and calculate thermal X-ray maps.Then these realistic sources and several types of simulated sources are used as the ground truth in the imaging simulations for both RHESSI and ASO-S/HXI.The different solutions are evaluated quantitatively by a number of means.The overall results suggest that EM,PIXON,and CLEAN are exceptional methods for sidelobe elimination,producing images with clear source details.Although MEM_GE,MEM_NJIT,VIS_WV and VIS_CS possess fast imaging processes and generate good images,they too possess associated imperfections unique to each method.The two forward fit algorithms,VF and FF,perform differently,and VF appears to be more robust and useful.We also demonstrated the imaging capability of HXI and available HXI algorithms.Furthermore,the effect of CBWF on image quality was investigated,and the optimal settings for both RHESSI and HXI were proposed. 展开更多
关键词 techniques image processing-Sun flares-Sun x-rays gamma rays
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Signal estimation bias in x-ray dark-field imaging using dual phase grating interferometer
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作者 Zhi-Li Wang Zun Zhang +1 位作者 Heng Chen Xin Ge 《Chinese Physics B》 2025年第3期550-558,共9页
In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean inten... In x-ray dark-field imaging using dual phase grating interferometer,multi-contrast signals are extracted from a set of acquired phase-stepping data by using the least-squares fitting algorithm.The extracted mean intensity,amplitude and visibility signals may be intrinsically biased.However,it is still unclear how large these biases are and how the data acquisition parameters influence the biases in the extracted signals.This work set out to address these questions.Analytical expressions of the biases of the extracted signals were theoretically derived by using a second-order Taylor series expansion.Extensive numerical simulations were performed to validate the theoretical results.It is illustrated that while the estimated mean intensity signal is always unbiased,the estimated amplitude and visibility signals are both positively biased.While the biases of the estimated amplitude signals are proportional to the inverse of the total number of phase steps,the biases of the estimated visibility signals are inversely proportional to the product of the total number of phase steps and the mean number of photons counted per phase step.Meanwhile,it is demonstrated that the dependence of the biases on the mean visibility is quite different from that of Talbot-Lau interferometer due to the difference in the intensity model.We expect that these results can be useful for data acquisition optimizations and interpretation of x-ray dark-field images. 展开更多
关键词 x-ray imaging dual phase grating interferometer dark-field imaging signal bias
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Thin layer identification using a theoretical X-ray logging while drilling(LWD)density imaging tool
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作者 Wen-Bin He Ji-Lin Fan +3 位作者 Qiong Zhang Ya Jin Wei Yuan Quan-Wen Zhang 《Petroleum Science》 2025年第6期2403-2413,共11页
With the increasing demand for oil exploration and subsurface resource development,density imaging plays an increasingly important role in identifying thin layers.However,conventional density imaging tools are limited... With the increasing demand for oil exploration and subsurface resource development,density imaging plays an increasingly important role in identifying thin layers.However,conventional density imaging tools are limited by poor vertical resolution and therefore suffer from errors in accurately estimating the thickness and relative dip angle of thin layers.This affects the accurate evaluation of thin layer oil and gas reserves.To address this issue,this study evaluates the feasibility of employing novel methods based on advanced tool design.First,an electronically controllable X-ray source is selected to replace the traditional Cs-137 source,aiming to improve the tool's vertical resolution while reducing the radioactive risks commonly associated with chemical sources.Simulation results show that the X-ray tool provides sufficient depth of investigation with better vertical resolution while maintaining the same level of measurement sensitivity.Once the tool design is established,Fisher's optimal segmentation method is improved to enhance the estimation of thin layer thickness and relative dip angle.This is completed by transforming identifying thin layer interface into a mathematical clustering problem.The thin layer interface is fitted using the nonlinear least squares method,which enables the calculation of its parameters.The results demonstrate a 38.5%reduction in RMSE(root mean square error)for thin layer thickness and a 33.7%reduction in RMSE for relative dip angle,demonstrating the superior performance of enhanced X-ray tool in thin layer identification.This study provides a new perspective on the design of density imaging tools and assessment of thin layer,which can help in future thin layer hydrocarbon reserves evaluation and development decisions. 展开更多
关键词 LWD density imaging x-ray tool design Thin layer identification
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Parallax-free panoramic X-ray imaging combined with minimally invasive plate osteosynthesis for treating proximal humeral shaft fractures
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作者 Wen-Jing Cheng Jing-Shun Lu +2 位作者 Zhou-Shan Tao Jia-Bing Xie Min Yang 《World Journal of Orthopedics》 2025年第5期44-50,共7页
BACKGROUND The objective of this study was to evaluate the use of combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with minimally invasive plate osteosynthesis(MIPO)in the man... BACKGROUND The objective of this study was to evaluate the use of combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with minimally invasive plate osteosynthesis(MIPO)in the management of proximal humeral shaft fractures.AIM To evaluate parallax-free panoramic X-ray images during surgery.METHODS A retrospective series of 17 proximal humeral shaft fractures were treated using combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with MIPO.The operating time and radiation exposure time were recorded,and early postoperative physical therapy and partial weight bearing were encouraged.Patients were followed at regular intervals and evaluated radiographically and clinically.RESULTS The mean operating time and radiation time were 73(range,49-95)minutes and 57(range:36-98)seconds,respectively.No complications occurred during the operation.All fractures healed at an average of 16.9(range:15-23)weeks.The average Constant-Murley score for all the patients was 89.5(range:75-100)points.None of the patients showed symptoms of vascular or nerve damage or wound infection.Three months after the operation,none of the patients developed subacromial impingement syndrome.No loosening or fracture of the implants occurred.The frontal and lateral radiographs showed good alignment.CONCLUSION We consider that MIPO with combined parallax-free panoramic X-ray imaging during surgery is an efficient method for treating proximal humeral shaft fractures,and could significantly reduce operative morbidity as well as lower the rate of intra-and postoperative complications. 展开更多
关键词 Minimally invasive plate osteosynthesis Proximal humeral shaft fractures Panoramic x-ray images COMPLICATIONS
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Epileptic brain network mechanisms and neuroimaging techniques for the brain network 被引量:1
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作者 Yi Guo Zhonghua Lin +1 位作者 Zhen Fan Xin Tian 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2637-2648,共12页
Epilepsy can be defined as a dysfunction of the brain network,and each type of epilepsy involves different brain-network changes that are implicated diffe rently in the control and propagation of interictal or ictal d... Epilepsy can be defined as a dysfunction of the brain network,and each type of epilepsy involves different brain-network changes that are implicated diffe rently in the control and propagation of interictal or ictal discharges.Gaining more detailed information on brain network alterations can help us to further understand the mechanisms of epilepsy and pave the way for brain network-based precise therapeutic approaches in clinical practice.An increasing number of advanced neuroimaging techniques and electrophysiological techniques such as diffusion tensor imaging-based fiber tra ctography,diffusion kurtosis imaging-based fiber tractography,fiber ball imagingbased tra ctography,electroencephalography,functional magnetic resonance imaging,magnetoencephalography,positron emission tomography,molecular imaging,and functional ultrasound imaging have been extensively used to delineate epileptic networks.In this review,we summarize the relevant neuroimaging and neuroelectrophysiological techniques for assessing structural and functional brain networks in patients with epilepsy,and extensively analyze the imaging mechanisms,advantages,limitations,and clinical application ranges of each technique.A greater focus on emerging advanced technologies,new data analysis software,a combination of multiple techniques,and the construction of personalized virtual epilepsy models can provide a theoretical basis to better understand the brain network mechanisms of epilepsy and make surgical decisions. 展开更多
关键词 electrophysiological techniques EPILEPSY functional brain network functional magnetic resonance imaging functional near-infrared spectroscopy machine leaning molecular imaging neuroimaging techniques structural brain network virtual epileptic models
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Advances in the application of auxiliary imaging techniques in parathyroid diseases
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作者 Lei Lu Hong-Qing Shang 《World Journal of Clinical Cases》 SCIE 2024年第17期2946-2950,共5页
Hypoparathyroidism is one of the main complications after total thyroidectomy,severely affecting patients’quality of life.How to effectively protect parathyroid function after surgery and reduce the incidence of hypo... Hypoparathyroidism is one of the main complications after total thyroidectomy,severely affecting patients’quality of life.How to effectively protect parathyroid function after surgery and reduce the incidence of hypoparathyroidism has always been a key research area in thyroid surgery.Therefore,precise localization of parathyroid glands during surgery,effective imaging,and accurate surgical resection have become hot topics of concern for thyroid surgeons.In response to this clinical phenomenon,this study compared several different imaging methods for parathyroid surgery,including nanocarbon,indocyanine green,near-infrared imaging techniques,and technetium-99m methoxyisobutylisonitrile combined with gamma probe imaging technology.The advantages and disadvantages of each method were analyzed,providing scientific recommendations for future parathyroid imaging.In recent years,some related basic and clinical research has also been conducted in thyroid surgery.This article reviewed relevant literature and provided an overview of the practical application progress of various imaging techniques in parathyroid surgery. 展开更多
关键词 imaging technique Parathyroid gland Thyroid surgery HYPOPARATHYROIDISM COMPLICATION
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Comparative Study of Four Classification Techniques for the Detection of Threats in Baggage from X-Ray Images
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作者 Boka Trinité Konan Hyacinthe Kouassi Konan +1 位作者 Jules Allani Olivier Asseu 《Open Journal of Applied Sciences》 2024年第12期3490-3499,共10页
Baggage screening is crucial for airport security. This paper examines various algorithms for firearm detection in X-ray images of baggage. The focus is on identifying steel barrel bores, which are essential for deton... Baggage screening is crucial for airport security. This paper examines various algorithms for firearm detection in X-ray images of baggage. The focus is on identifying steel barrel bores, which are essential for detonation. For this, the study uses a set of 22,000 X-ray scanned images. After preprocessing with filtering techniques to improve image quality, deep learning methods, such as Convolutional Neural Networks (CNNs), are applied for classification. The results are also compared with Autoencoder and Random Forest algorithms. The results are validated on a second dataset, highlighting the advantages of the adopted approach. Baggage screening is a very important part of the risk assessment and security screening process at airports. Automating the detection of dangerous objects from passenger baggage X-ray scanners can speed up and increase the efficiency of the entire security procedure. 展开更多
关键词 Deep Learning Baggage Control Convolutional Neural Networks image Filtering Object Detection Algorithms x-ray images Autoencoder Random Forests
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Tests of Solar X-Ray Image Reconstruction:A New Index for Assessing Image Quality 被引量:1
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作者 Zhen-Tong Li Wen-Hui Yu +2 位作者 Yang Su Wei Chen Wei-Qun Gan 《Research in Astronomy and Astrophysics》 2025年第3期76-89,共14页
Indirect X-ray modulation imaging has been adopted in a number of solar missions and provided reconstructed X-ray images of solar flares that are of great scientific importance.However,the assessment of the image qual... Indirect X-ray modulation imaging has been adopted in a number of solar missions and provided reconstructed X-ray images of solar flares that are of great scientific importance.However,the assessment of the image quality of the reconstruction is still difficult,which is particularly useful for scheme design of X-ray imaging systems,testing and improvement of imaging algorithms,and scientific research of X-ray sources.Currently,there is no specified method to quantitatively evaluate the quality of X-ray image reconstruction and the point-spread function(PSF)of an X-ray imager.In this paper,we propose percentage proximity degree(PPD)by considering the imaging characteristics of X-ray image reconstruction and in particular,sidelobes and their effects on imaging quality.After testing a variety of imaging quality assessments in six aspects,we utilized the technique for order preference by similarity to ideal solution to the indices that meet the requirements.Then we develop the final quality index for X-ray image reconstruction,QuIX,which consists of the selected indices and the new PPD.QuIX performs well in a series of tests,including assessment of instrument PSF and simulation tests under different grid configurations,as well as imaging tests with RHESSI data.It is also a useful tool for testing of imaging algorithms,and determination of imaging parameters for both RHESSI and ASO-S/Hard X-ray Imager,such as field of view,beam width factor,and detector selection. 展开更多
关键词 SUN flares-Sun x-rays gamma-rays-techniques image processing
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X-ray excited Mn^(2+)-doped persistent luminescence materials with biological window emission for in vivo bioimaging 被引量:5
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作者 Hanrun Zheng Lin Liu +6 位作者 Yi’ang Li Rui Rong Liang Song Junpeng Shi Jing Teng Xia Sun Yun Zhang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第1期28-35,I0001,共9页
In recent years,persistent luminescence materials(PLMs)excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity bioimaging.Transition metal Mn^(2+)is an i... In recent years,persistent luminescence materials(PLMs)excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity bioimaging.Transition metal Mn^(2+)is an ideal emission center,but few studies focus on Mn^(2+)-doped PLMs with X-ray excitation and biological window emission.Here,we report a Mn^(2+)-doped PLM,LiYGeO_(4):Mn^(2+)(LYGM),with excellent biological window persistent luminescence emission.After excitation by UV,LYGM produces a durable biological window of persistent luminescence emission at 660 nm for up to 20 h.More importantly.LYGM can be repeatedly excited by X-rays,resulting in long-term biological window persistent luminescence emission.In addition,we obtain LYGM around 200 nm in diameter by ball milling and centrifugation and improve its biocompatibility by surface modification to apply it to in vivo imaging in mice.After LYGM are injected into mice through the tail vein,in situ excitation of X-rays can be achieved.After the persistent luminescence decays,LYGM can be re-excited for repeated imaging.Therefore,LYGM shows potential prospects for in vivo deep tissue and long-term bioimaging. 展开更多
关键词 Persistent luminescence x-ray Biological window In vivo imaging Rare earths
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Advancing osteoarthritis research:the role of AI in clinical,imaging and omics fields 被引量:1
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作者 Jingfeng Ou Jin Zhang +4 位作者 Momen Alswadeh Zhenglin Zhu Jijun Tang Hongxun Sang Ke Lu 《Bone Research》 2025年第2期307-319,共13页
Osteoarthritis(OA)is a degenerative joint disease with significant clinical and societal impact.Traditional diagnostic methods,including subjective clinical assessments and imaging techniques such as X-rays and MRIs,a... Osteoarthritis(OA)is a degenerative joint disease with significant clinical and societal impact.Traditional diagnostic methods,including subjective clinical assessments and imaging techniques such as X-rays and MRIs,are often limited in their ability to detect early-stage OA or capture subtle joint changes.These limitations result in delayed diagnoses and inconsistent outcomes.Additionally,the analysis of omics data is challenged by the complexity and high dimensionality of biological datasets,making it difficult to identify key molecular mechanisms and biomarkers.Recent advancements in artificial intelligence(AI)offer transformative potential to address these challenges.This review systematically explores the integration of AI into OA research,focusing on applications such as AI-driven early screening and risk prediction from electronic health records(EHR),automated grading and morphological analysis of imaging data,and biomarker discovery through multi-omics integration.By consolidating progress across clinical,imaging,and omics domains,this review provides a comprehensive perspective on how AI is reshaping OA research.The findings have the potential to drive innovations in personalized medicine and targeted interventions,addressing longstanding challenges in OA diagnosis and management. 展开更多
关键词 subjective clinical assessments analysis omics data degenerative joint disease OSTEOARTHRITIS imaging techniques clinical assessment biological datasetsmaking diagnostic methodsincluding
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Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging 被引量:2
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作者 Jin-Xiao Zheng Zi-An Zhou +6 位作者 Tiao Feng Hui Li Cheng-Hua Sun NüWang Yang Tian Yong Zhao Shu-Yun Zhou 《Rare Metals》 SCIE EI CAS CSCD 2024年第1期175-185,共11页
The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging... The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and waterproofing.Here, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development. 展开更多
关键词 Two-dimensional perovskite HYDROPHOBIC SCINTILLATORS Underwater x-ray imaging Underwater nondestructive testing technology
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Two-Dimensional Perovskite Single Crystals for High-Performance X-ray Imaging and Exploring MeV X-ray Detection 被引量:1
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作者 Xieming Xu Yiheng Wu +5 位作者 Yi Zhang Xiaohui Li Fang Wang Xiaoming Jiang Shaofan Wu Shuaihua Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第1期139-146,共8页
Scintillation semiconductors play increasingly important medical diagnosis and industrial inspection roles.Recently,two-dimensional(2D)perovskites have been shown to be promising materials for medical X-ray imaging,bu... Scintillation semiconductors play increasingly important medical diagnosis and industrial inspection roles.Recently,two-dimensional(2D)perovskites have been shown to be promising materials for medical X-ray imaging,but they are mostly used in low-energy(≤130 keV)regions.Direct detection of MeV X-rays,which ensure thorough penetration of the thick shell walls of containers,trucks,and aircraft,is also highly desired in practical industrial applications.Unfortunately,scintillation semiconductors for high-energy X-ray detection are currently scarce.Here,This paper reports a 2D(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single crystal with outstanding sensitivity and stability toward X-ray radiation that provides an ultra-wide detectable X-ray range of between 8.20 nGy_(air)s^(-1)(50 keV)and 15.24 mGy_(air)s^(-1)(9 MeV).The(C_(4)H_(9)NH_(3))_(2)PbBr_(4)single-crystal detector with a vertical structure is used for high-performance X-ray imaging,delivering a good spatial resolution of 4.3 Ip mm^(-1)in a plane-scan imaging system.Low ionic migration in the 2D perovskite enables the vertical device to be operated with hundreds of keV to MeV X-ray radiation at high bias voltages,leading to a sensitivity of 46.90μC Gy_(air)-1 cm^(-2)(-1.16 Vμm^(-1))with 9 MeV X-ray radiation,demonstrating that 2D perovskites have enormous potential for high-energy industrial applications. 展开更多
关键词 MeV x-ray detection single-crystal x-ray detectors two-dimensional perovskites x-ray imaging
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Insights into the hydrogen evolution reaction in vanadium redox flow batteries:A synchrotron radiation based X-ray imaging study 被引量:1
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作者 Kerstin Köble Alexey Ershov +7 位作者 Kangjun Duan Monja Schilling Alexander Rampf Angelica Cecilia TomášFaragó Marcus Zuber Tilo Baumbach Roswitha Zeis 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期132-144,共13页
The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency losses.Thus,a deeper understanding of this process and the accompanying bubble fo... The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency losses.Thus,a deeper understanding of this process and the accompanying bubble formation is crucial.This benchmarking study locally analyzes the bubble distribution in thick,porous electrodes for the first time using deep learning-based image segmentation of synchrotron X-ray micro-tomograms.Each large three-dimensional data set was processed precisely in less than one minute while minimizing human errors and pointing out areas of increased HER activity in VRFBs.The study systematically varies the electrode potential and material,concluding that more negative electrode potentials of-200 m V vs.reversible hydrogen electrode(RHE)and lower cause more substantial bubble formation,resulting in bubble fractions of around 15%–20%in carbon felt electrodes.Contrarily,the bubble fractions stay only around 2%in an electrode combining carbon felt and carbon paper.The detected areas with high HER activity,such as the border subregion with more than 30%bubble fraction in carbon felt electrodes,the cutting edges,and preferential spots in the electrode bulk,are potential-independent and suggest that larger electrodes with a higher bulk-to-border ratio might reduce HER-related performance losses.The described combination of electrochemical measurements,local X-ray microtomography,AI-based segmentation,and 3D morphometric analysis is a powerful and novel approach for local bubble analysis in three-dimensional porous electrodes,providing an essential toolkit for a broad community working on bubble-generating electrochemical systems. 展开更多
关键词 Vanadium redox flow battery Synchrotron x-ray imaging Tomography Hydrogen evolution reaction Gas bubbles Deep learning
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Optimization of aerodynamic lens-design method for single-particle imaging in XFELs
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作者 Dong-Hao Lu Xiao-Kai Li +3 位作者 Hui Luan Chen-Xi Wei Jia-Dong Fan Huai-Dong Jiang 《Nuclear Science and Techniques》 2025年第9期19-32,共14页
Ultrabright femtosecond X-ray pulses generated by X-ray free-electron lasers(XFELs)enable the high-resolution determination of nanoparticle structures without crystallization or freezing.As each particle that interact... Ultrabright femtosecond X-ray pulses generated by X-ray free-electron lasers(XFELs)enable the high-resolution determination of nanoparticle structures without crystallization or freezing.As each particle that interacts with the pulse is destroyed,an aerodynamic lens(ADL)is used to update the particles by focusing them into a narrow beam in real time.Current single-particle imaging(SPI)experiments are limited by an insufficient number of diffraction patterns;therefore,optimized ADLs are required to improve the hit rate and signal-to-noise ratio,particularly for small particles.Herein,an efficient and simple method for designing ADLs and a new ADL specifically designed for SPI using this method are presented.A new method is proposed based on the functional relationship between a key parameter and its influencing parameters in the ADL,which is established through theoretical analysis and numerical simulations.A detailed design process for the new ADL is also introduced.Both simulations and experiments are performed to characterize the behavior of the particles in the ADL.The results show that particles with diameters ranging from 30 to 500 nm can be effectively focused into a narrow beam.In particular,particles smaller than 100 nm exhibit better performance at lower flow rates than the injector currently used in SPI.The new ADL increases the beam density and reduces the gas background noise.This new method facilitates the design of ADLs for SPI and has potential applications in other fields that utilize focused aerosol beams. 展开更多
关键词 Aerodynamic lens Stokes number Aerosol sample-delivery system Single-particle imaging x-ray free-electron laser
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Emerging non-invasive imaging biomarkers of Ki-67 in pancreatic cancer:Toward predictive precision oncology
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作者 Yi-Xin Wu Rui Tian +3 位作者 Xiao-Wen Li Jie-Yu Guo Jing-Feng Tang Ce-Fan Zhou 《World Journal of Gastrointestinal Oncology》 2025年第11期1-10,共10页
The proliferative index of Ki-67 in pancreatic ductal adenocarcinoma(PDAC)exhibits strong correlations with tumor progression and prognosis,holding significant clinical implications.Yang et al employed contrast-enhanc... The proliferative index of Ki-67 in pancreatic ductal adenocarcinoma(PDAC)exhibits strong correlations with tumor progression and prognosis,holding significant clinical implications.Yang et al employed contrast-enhanced ultrasound(CEUS)to indirectly evaluate neovascularization in pancreatic cancer lesions.Specific CEUS parameters demonstrated significant diagnostic value in assessing Ki-67 expression.The falling slope 50%achieved an area under the curve of 0.838.Meanwhile,the rise slope 10%-90%exhibited superior overall diagnostic accuracy(area under the curve=0.863),showing a sensitivity of 0.92 and a moderate specificity of 0.759.These values demonstrate specificity in differentiating between low and high Ki-67 expression groups.This study effectively addresses the critical need for a non-invasive assessment of pancreatic cancer aggressiveness via Ki-67 expression.These findings strongly support the translational potential of CEUS biomarkers for non-invasive Ki-67 assessment and treatment stratification in PDAC.While Yang et al demonstrated exhibited encouraging methodologies,its retrospective design,modest sample size,and single-center nature may impede generalizability,pending validation in multi-institutional cohorts.We recommend expanding the sample size to enhance representativeness and adopting prospective studies integrating multimodal imaging techniques,such as magnetic resonance imaging and positron emission tomography to improve diagnostic reliability.This study is the first to integrate insights from CEUS,magnetic resonance imaging,and positron emission tomography for Ki-67 expression assessment in PDAC.Building on this innovation,we focus this article on recent advances in the clinical diagnosis of pancreatic cancer,aiming to provide insights for advancing research in this field. 展开更多
关键词 Ki-67 expression Pancreatic cancer Contrast-enhanced ultrasound imaging techniques Clinical diagnosis
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Multiple imaging modalities in intraocular silicone oil emulsification and its related complications
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作者 Jia-Wei Wang Jing Su +5 位作者 Fei-Yan Ma Jin Wang Ying Liu Jin-Xin Shi Jing-Xue Ma Dan-Yan Liu 《International Journal of Ophthalmology(English edition)》 2025年第7期1333-1340,共8页
AIM:To elucidate the manifestations and associated complications observed in patients with intraocular silicone oil(SO)emulsification through multiple imaging modalities.METHODS:This single-center,observational,retros... AIM:To elucidate the manifestations and associated complications observed in patients with intraocular silicone oil(SO)emulsification through multiple imaging modalities.METHODS:This single-center,observational,retrospective study included 116 patients who underwent pars plana vitrectomy(PPV)with SO injection for retinal detachment(RD),followed by subsequent SO removal at the Second Hospital of Hebei Medical University from January 2013 to January 2023.Comprehensive records of ophthalmic examinations utilizing multiple imaging techniques were maintained.RESULTS:The study comprised 56 females and 60 males,with a mean age of 52.75±13.6y.The mean follow-up duration for SO tamponade was 9.04±11.33mo(range:1-84mo).Among the participants,59 patients were diagnosed with SO emulsification,while 57 patients were in the SO unemulsified group.Patients with SO emulsification had a significantly prolonged SO tamponade duration(P<0.01).Multiple imaging techniques revealed notable signs of SO emulsification and its complications,such as 4 cases(3.4%)with posterior corneal SO-like keratic precipitates(KP)observed by anterior segment photography,23 cases(19.8%)exhibiting spherical high-reflection signals in the inter-retina,retinal pigment epithelium,or choroid detected by Spectralis spectral domain optical coherence tomography(SD-OCT),4 cases(3.4%)showing slow movement of emulsified SO droplets within retinal vessels during fluorescein angiography(FFA),plain and enhanced head magnetic resonance imaging(MRI)images of these four patients did not detect emulsified SO in the lateral ventricles,suprasellar cistern,subarachnoid space,third ventricle,fourth ventricle,or other intracranial locations.CONCLUSION:Intraocular emulsified SO can lead to damage in both anterior and posterior segment tissues,encompassing corneal degeneration,cataracts,glaucoma,retinal and choroid inflammation.Objective multiple imaging techniques such as anterior segment photography,SD-OCT,FFA,and MRI offer comprehensive evaluation and diagnosis of SO emulsification and its associated complications. 展开更多
关键词 silicone oil emulsification multiple imaging techniques Spectralis spectral domain optical coherence tomography fluorescein angiography magnetic resonance imaging
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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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