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翻译博士专业学位(DTI)人才培养模式内容探究——以CIUTI院校翻译类博士专业培养特征为中心
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作者 李忠辉 《外语与翻译》 2024年第2期75-81,共7页
作为高等教育领域博士阶段人才培养的新生事物,DTI作为翻译博士专业学位教育还处于办学前期,人才培养模式仍处于探讨阶段,需在培养拔尖翻译人才的办学理念指导下,依据我国对翻译博士专业学位人才培养的最新要求,借鉴CIUTI高校在翻译类... 作为高等教育领域博士阶段人才培养的新生事物,DTI作为翻译博士专业学位教育还处于办学前期,人才培养模式仍处于探讨阶段,需在培养拔尖翻译人才的办学理念指导下,依据我国对翻译博士专业学位人才培养的最新要求,借鉴CIUTI高校在翻译类博士领域的办学经验,设置凸显DTI设立宗旨的专业方向,选拔外语好且有翻译实践经验者的招生制度,建立以专业方向为主的实践实习课程体系,利用多元合作方式补充师资队伍,与用人单位深度合作开展翻译实习,设置考察解决问题实际能力的毕业条件等,推动我国DTI教育良性发展,培养大量拔尖翻译类人才,服务中国文化“走出去”战略。 展开更多
关键词 dti 翻译 培养模式 CIUTI 建议
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磁共振DTI技术在布鲁氏菌性脊柱炎中的诊断效能及相关参数分析
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作者 宋丽俊 鲁雪红 郭辉 《影像研究与医学应用》 2024年第7期12-14,共3页
目的:探究磁共振弥散张量成像(DTI)技术在布氏杆菌脊柱炎(BS)中的诊断效能及相关参数。方法:选择2020年8月—2022年7月于新疆医科大学附属中医医院就诊的疑似BS的40例患者作为研究对象,均行CT及磁共振DTI技术检查。将实验室检测及细菌... 目的:探究磁共振弥散张量成像(DTI)技术在布氏杆菌脊柱炎(BS)中的诊断效能及相关参数。方法:选择2020年8月—2022年7月于新疆医科大学附属中医医院就诊的疑似BS的40例患者作为研究对象,均行CT及磁共振DTI技术检查。将实验室检测及细菌学培养结果作为“金标准”,分析CT及磁共振DTI技术在BS中的诊断价值;对BS患者进行随访,对比治疗前及治疗后的各向异性分数(FA)值及表观弥散系数(ADC)值。结果:磁共振DTI在BS诊断中准确率高于CT检查,差异有统计学意义(P<0.05);两者灵敏度、特异度、阳性预测值及阴性预测值对比,差异无统计学意义(P>0.05)。治疗后急性期与亚急性期的ADC值及FA值均小于治疗前,而慢性期治疗后ADC值小于治疗前,FA值大于治疗前,差异有统计学意义(P<0.05)。结论:磁共振DTI技术在BS诊断中准确率较高,可依据ADC及FA值变化判断患者疾病时期,同时对指导临床治疗具有重要作用,值得推广应用。 展开更多
关键词 布鲁氏菌性脊柱炎 磁共振成像 弥散张量成像 诊断效能
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DTI联合DWI对急性脑梗死早期缺血半暗带的定量评估价值
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作者 李静 张嘉俊 王可 《临床医学工程》 2024年第7期785-786,共2页
目的分析磁共振弥散张量成像(DTI)联合弥散加权成像(DWI)对急性脑梗死(ACI)早期缺血半暗带(IP)的定量评估价值。方法选取ACI患者80例,均行磁共振DTI和DWI检查,根据患者发病时间将其分为超急性期组(<6h,n=24)、急性期组(6~24h,n=26)... 目的分析磁共振弥散张量成像(DTI)联合弥散加权成像(DWI)对急性脑梗死(ACI)早期缺血半暗带(IP)的定量评估价值。方法选取ACI患者80例,均行磁共振DTI和DWI检查,根据患者发病时间将其分为超急性期组(<6h,n=24)、急性期组(6~24h,n=26)和亚急性期组(24~72h,n=30),比较ACI患者梗死中心区、IP区、对侧镜像区的平均扩散系数(DCavg)、表观扩散系数(ADC)、异性指数(FA)值,并比较ACI患者不同发病时期IP区的rDCavg、rADC、rFA值。结果ACI患者不同区域DCavg、ADC、FA值比较:梗死中心区<IP区<对侧镜像区(P<0.05)。ACI患者不同发病时期IP区rDCavg、rADC、rFA值比较:超急性期组>急性期组>亚急性期组(P<0.05)。结论DTI联合DWI检查的相关定量参数对于ACI早期IP具有较高的评估价值,临床可借鉴应用。 展开更多
关键词 急性脑梗死 缺血半暗带 弥散张量成像 弥散加权成像 定量参数 评估价值
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Two-photon live imaging of direct glia-to-neuron conversion in the mouse cortex 被引量:1
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作者 Zongqin Xiang Shu He +13 位作者 Rongjie Chen Shanggong Liu Minhui Liu Liang Xu Jiajun Zheng Zhouquan Jiang Long Ma Ying Sun Yongpeng Qin Yi Chen Wen Li Xiangyu Wang Gong Chen Wenliang Lei 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1781-1788,共8页
Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for ... Over the past decade,a growing number of studies have reported transcription factor-based in situ reprogramming that can directly conve rt endogenous glial cells into functional neurons as an alternative approach for n euro regeneration in the adult mammalian central ne rvous system.Howeve r,many questions remain regarding how a terminally differentiated glial cell can transform into a delicate neuron that forms part of the intricate brain circuitry.In addition,concerns have recently been raised around the absence of astrocyte-to-neuron conversion in astrocytic lineage-tra cing mice.In this study,we employed repetitive two-photon imaging to continuously capture the in situ astrocyte-to-neuron conversion process following ecto pic expression of the neural transcription factor NeuroD1 in both prolife rating reactive astrocytes and lineage-tra ced astrocytes in the mouse cortex.Time-lapse imaging over several wee ks revealed the ste p-by-step transition from a typical astrocyte with numero us short,tapered branches to a typical neuro n with a few long neurites and dynamic growth cones that actively explored the local environment.In addition,these lineage-converting cells were able to migrate ra dially or to ngentially to relocate to suitable positions.Furthermore,two-photon Ca2+imaging and patch-clamp recordings confirmed that the newly generated neuro ns exhibited synchronous calcium signals,repetitive action potentials,and spontaneous synaptic responses,suggesting that they had made functional synaptic connections within local neural circuits.In conclusion,we directly visualized the step-by-step lineage conversion process from astrocytes to functional neurons in vivo and unambiguously demonstrated that adult mammalian brains are highly plastic with respect to their potential for neuro regeneration and neural circuit reconstruction. 展开更多
关键词 astrocyte-to-neuron conversion Ca2+imaging direct lineage conversion GLIA ASTROCYTE in vivo reprogramming lineage-tracing mice NeuroD1 NEURON two-photon imaging
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弓状束微结构改变对轻度认知功能影响的DTI研究
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作者 韩松霖 张健 《中国临床新医学》 2024年第1期87-93,共7页
目的 基于磁共振弥散张量成像(DTI)技术探讨弓状束走行区域内腔隙性脑梗死患者的弓状束微结构改变对轻度认知功能的影响。方法 选择2022年9月至2023年6月双鸭山市人民医院收治的弓状束走行区域内腔隙性脑梗死患者64例,根据蒙特利尔认知... 目的 基于磁共振弥散张量成像(DTI)技术探讨弓状束走行区域内腔隙性脑梗死患者的弓状束微结构改变对轻度认知功能的影响。方法 选择2022年9月至2023年6月双鸭山市人民医院收治的弓状束走行区域内腔隙性脑梗死患者64例,根据蒙特利尔认知评估(MoCA)量表评分将其分为轻度认知障碍(MCI)组(MoCA量表评分≥16分且<26分,35例)和非MCI组(MoCA量表评分≥26分,29例)。于同期纳入年龄、性别、受教育年限与患者相匹配的20名健康体检者作为对照组。研究对象均行核磁头部平扫加DTI检查,比较MCI组和非MCI组不同病灶数同侧弓状束DTI弥散指标水平和MoCA量表评分情况。结果 MCI组病灶数N<2者,左侧弓状束各向异性分数(FA)水平和MoCA量表评分高于2≤N<4者及N≥4者,右侧弓状束MoCA量表评分高于2≤N<4者及N≥4者;病灶数2≤N<4者,左侧、右侧弓状束MoCA量表评分均高于N≥4者,差异有统计学意义(P<0.05)。非MCI组病灶数N<2者,左侧、右侧弓状束FA水平均高于N≥4者,MD水平均低于N≥4者,且左侧弓状束MoCA量表评分高于2≤N<4者及N≥4者,右侧弓状束MoCA量表评分高于N≥4者;病灶数2≤N<4者,左侧、右侧弓状束MD水平均低于N≥4,差异有统计学意义(P<0.05)。结论 腔隙性脑梗死患者弓状束微结构改变与MCI有关,腔隙性脑梗死病灶数量越多,FA水平越低,弓状束损伤越严重,MoCA量表评分越低。对弓状束走行区域内的腔隙性脑梗死患者行核磁头部平扫加DTI检查弓状束微结构改变并结合MoCA量表评分可以作为评估MCI及预防阿尔茨海默病(AD)的重要方法。 展开更多
关键词 弥散张量成像 腔隙性脑梗死 弓状束微结构 认知功能
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Magnetic resonance imaging of extraocular rectus muscles abnormalities in acute acquired concomitant esotropia 被引量:1
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作者 Jia-Yu Chen Li-Rong Zhang +5 位作者 Jia-Wen Liu Jie Hao Hui-Xin Li Qiong-Yue Zhang Zhao-Hui Liu Jing Fu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期119-125,共7页
AIM:To investigate the difference of medial rectus(MR)and lateral rectus(LR)between acute acquired concomitant esotropia(AACE)and the healthy controls(HCs)detected by magnetic resonance imaging(MRI).METHODS:A case-con... AIM:To investigate the difference of medial rectus(MR)and lateral rectus(LR)between acute acquired concomitant esotropia(AACE)and the healthy controls(HCs)detected by magnetic resonance imaging(MRI).METHODS:A case-control study.Eighteen subjects with AACE and eighteen HCs were enrolled.MRI scanning data were conducted in target-controlled central gaze with a 3-Tesla magnetic resonance scanner.Extraocular muscles(EOMs)were scanned in contiguous image planes 2-mm thick spanning the EOM origins to the globe equator.To form posterior partial volumes(PPVs),the LR and MR cross-sections in the image planes 8,10,12,and 14 mm posterior to the globe were summed and multiplied by the 2-mm slice thickness.The data were classified according to the right eye,left eye,dominant eye,and non-dominant eye,and the differences in mean cross-sectional area,maximum cross-sectional area,and PPVs of the MR and LR muscle in the AACE group and HCs group were compared under the above classifications respectively.RESULTS:There were no significant differences between the two groups of demographic characteristics.The mean cross-sectional area of the LR muscle was significantly greater in the AACE group than that in the HCs group in the non-dominant eyes(P=0.028).The maximum cross-sectional area of the LR muscle both in the dominant and non-dominant eye of the AACE group was significantly greater than the HCs group(P=0.009,P=0.016).For the dominant eye,the PPVs of the LR muscle were significantly greater in the AACE than that in the HCs group(P=0.013),but not in the MR muscle(P=0.698).CONCLUSION:The size and volume of muscles dominant eyes of AACE subjects change significantly to overcome binocular diplopia.The LR muscle become larger to compensate for the enhanced convergence in the AACE. 展开更多
关键词 acute acquired concomitant esotropia magnetic resonance imaging extraocular muscles
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Potential applications of 7 Tesla magnetic resonance imaging in paediatric neuroimaging:Feasibility and challenges 被引量:1
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作者 Arosh S Perera Molligoda Arachchige Letterio S Politi 《World Journal of Clinical Pediatrics》 2024年第2期1-6,共6页
The integration of 7 Tesla magnetic resonance imaging(7 T MRI)in adult patients has marked a revolutionary stride in radiology.In this article we explore the feasibility of 7 T MRI in paediatric practice,emphasizing i... The integration of 7 Tesla magnetic resonance imaging(7 T MRI)in adult patients has marked a revolutionary stride in radiology.In this article we explore the feasibility of 7 T MRI in paediatric practice,emphasizing its feasibility,applications,challenges,and safety considerations.The heightened resolution and tissue contrast of 7 T MRI offer unprecedented diagnostic accuracy,particularly in neuroimaging.Applications range from neuro-oncology to neonatal brain imaging,showcasing its efficacy in detecting subtle structural abnormalities and providing enhanced insights into neurological conditions.Despite the promise,challenges such as high cost,discomfort,and safety concerns necessitate careful consideration.Research suggests that,with precautions,7 T MRI is feasible in paediatrics,yet ongoing studies and safety assessments are imperative. 展开更多
关键词 7 Tesla magnetic resonance imaging Pediatric imaging FEASIBILITY CHALLENGES
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In vivo imaging reveals a synchronized correlation among neurotransmitter dynamics during propofol and sevoflurane anesthesia 被引量:1
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作者 Gao-Lin Qiu Li-Jun Peng +6 位作者 Peng Wang Zhi-Lai Yang Ji-Qian Zhang Hu Liu Xiao-Na Zhu Jin Rao Xue-Sheng Liu 《Zoological Research》 SCIE CSCD 2024年第3期679-690,共12页
General anesthesia is widely applied in clinical practice.However,the precise mechanism of loss of consciousness induced by general anesthetics remains unknown.Here,we measured the dynamics of five neurotransmitters,i... General anesthesia is widely applied in clinical practice.However,the precise mechanism of loss of consciousness induced by general anesthetics remains unknown.Here,we measured the dynamics of five neurotransmitters,includingγ-aminobutyric acid,glutamate,norepinephrine,acetylcholine,and dopamine,in the medial prefrontal cortex and primary visual cortex of C57BL/6 mice through in vivo fiber photometry and genetically encoded neurotransmitter sensors under anesthesia to reveal the mechanism of general anesthesia from a neurotransmitter perspective.Results revealed that the concentrations of γ-aminobutyric acid,glutamate,norepinephrine,and acetylcholine increased in the cortex during propofol-induced loss of consciousness.Dopamine levels did not change following the hypnotic dose of propofol but increased significantly following surgical doses of propofol anesthesia.Notably,the concentrations of the five neurotransmitters generally decreased during sevoflurane-induced loss of consciousness.Furthermore,the neurotransmitter dynamic networks were not synchronized in the non-anesthesia groups but were highly synchronized in the anesthetic groups.These findings suggest that neurotransmitter dynamic network synchronization may cause anesthetic-induced loss of consciousness. 展开更多
关键词 General anesthesia Loss of consciousness In vivo neurotransmitter imaging Medial prefrontal cortex Primary visual cortex
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Outcomes and efficacy of magnetic resonance imaging-compatible sacral nerve stimulator for management of fecal incontinence: A multi-institutional study 被引量:1
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作者 Binit Katuwal Amy Thorsen +5 位作者 Kunal Kochar Ryba Bhullar Ray King Ernesto Raul Drelichman Vijay K Mittal Jasneet Singh Bhullar 《World Journal of Radiology》 2024年第2期32-39,共8页
BACKGROUND Fecal incontinence(FI)is an involuntary passage of fecal matter which can have a significant impact on a patient’s quality of life.Many modalities of treatment exist for FI.Sacral nerve stimulation is a we... BACKGROUND Fecal incontinence(FI)is an involuntary passage of fecal matter which can have a significant impact on a patient’s quality of life.Many modalities of treatment exist for FI.Sacral nerve stimulation is a well-established treatment for FI.Given the increased need of magnetic resonance imaging(MRI)for diagnostics,the In-terStim which was previously used in sacral nerve stimulation was limited by MRI incompatibility.Medtronic MRI-compatible InterStim was approved by the United States Food and Drug Administration in August 2020 and has been widely used.AIM To evaluate the efficacy,outcomes and complications of the MRI-compatible InterStim.METHODS Data of patients who underwent MRI-compatible Medtronic InterStim placement at UPMC Williamsport,University of Minnesota,Advocate Lutheran General Hospital,and University of Wisconsin-Madison was pooled and analyzed.Patient demographics,clinical features,surgical techniques,complications,and outcomes were analyzed.Strengthening the Reporting of Observational studies in Epidemiology(STROBE)cross-sectional reporting guidelines were used.RESULTS Seventy-three patients had the InterStim implanted.The mean age was 63.29±12.2 years.Fifty-seven(78.1%)patients were females and forty-two(57.5%)patients had diabetes.In addition to incontinence,overlapping symptoms included diarrhea(23.3%),fecal urgency(58.9%),and urinary incontinence(28.8%).Fifteen(20.5%)patients underwent Peripheral Nerve Evaluation before proceeding to definite implant placement.Thirty-two(43.8%)patients underwent rechargeable InterStim placement.Three(4.1%)patients needed removal of the implant.Migration of the external lead connection was observed in 7(9.6%)patients after the stage I procedure.The explanation for one patient was due to infection.Seven(9.6%)patients had other complications like nerve pain,hematoma,infection,lead fracture,and bleeding.The mean follow-up was 6.62±3.5 mo.Sixty-eight(93.2%)patients reported significant improvement of symptoms on follow-up evaluation.CONCLUSION This study shows promising results with significant symptom improvement,good efficacy and good patient outcomes with low complication rates while using MRI compatible InterStim for FI.Further long-term follow-up and future studies with a larger patient population is recommended. 展开更多
关键词 Fecal incontinence Sacral nerve stimulation InterStim Magnetic resonance imaging Sacral neuromodulation
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Intravascular photoacoustic and optical coherence tomography imaging dual-mode system for detecting spontaneous coronary artery dissection: A feasibility study 被引量:1
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作者 Yongwei Wang Yuyang Wan Zhongjiang Chen 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期77-86,共10页
In this work,we present an intravascular dual-mode endoscopic system capable of both intravascular photoacoustic imaging(IVPAI)and intravascular optical coherence tomography(IVOCT)for recognizing spontaneous coronary ... In this work,we present an intravascular dual-mode endoscopic system capable of both intravascular photoacoustic imaging(IVPAI)and intravascular optical coherence tomography(IVOCT)for recognizing spontaneous coronary artery dissection(SCAD)phantoms.IVPAI provides high-resolution and high-penetration images of intramural hematoma(IMH)at different depths,so it is especially useful for imaging deep blood clots associated with imaging phantoms.IVOCT can readily visualize the double-lumen morphology of blood vessel walls to identify intimal tears.We also demonstrate the capability of this dual-mode endoscopic system using mimicking phantoms and biological samples of blood clots in ex vivo porcine arteries.The results of the experiments indicate that the combined IVPAI and IVOCT technique has the potential to provide a more accurate SCAD assessment method for clinical applications. 展开更多
关键词 Spontaneous coronary artery dissection(SCAD) intravascular optical coherence tomography(IVOCT) intravascular photoacoustic imaging(IVPAI)
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柴油机DTI试验影响温升因素的研究
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作者 余国成 王再兴 +2 位作者 王磊 张俊杰 檀在先 《内燃机与配件》 2024年第13期4-6,共3页
目前国六和非道路四阶段法规对柴油机尾气中颗粒限值越来越严格,对颗粒捕集器DPF的综合性能要求很严苛,其中一项就是在再生过程中,车辆突然降至怠速时因排气流量瞬间降低,而DPF内温度很高,热量无法快速排出,会导致DPF内部温度快速升高,... 目前国六和非道路四阶段法规对柴油机尾气中颗粒限值越来越严格,对颗粒捕集器DPF的综合性能要求很严苛,其中一项就是在再生过程中,车辆突然降至怠速时因排气流量瞬间降低,而DPF内温度很高,热量无法快速排出,会导致DPF内部温度快速升高,非常考验DPF载体耐热能力,如果不摸清DPF的耐热能力和温度极限,确定DPF一个安全累碳量,后期市场上极大可能产生很高的故障率,造成成本提升和信誉降低。所以需要对载体的耐热应力性能及其耐久性能进行验证摸底,DTI试验就是测试DPF耐高温的一种方法,研究DTI试验测试影响因素,有助于很好的把控试验过程,规避试验失败的因素,提升试验成功率,降低重复测试成本和试验周期。 展开更多
关键词 柴油机 DPF 高温 dti 影响因素
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DKI及DTI在鉴别诊断低级别胶质瘤与脑炎中的价值
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作者 赵锴 马潇越 +6 位作者 程敬亮 高安康 白洁 王沛沛 赵国桦 高而远 齐金博 《磁共振成像》 CAS CSCD 北大核心 2024年第2期1-6,55,共7页
目的评估MR扩散峰度成像(diffusion kurtosis imaging,DKI)及扩散张量成像(diffusion-tensor imaging,DTI)在鉴别低级别胶质瘤与脑炎中的价值。材料与方法回顾性分析58例低级别胶质瘤或脑炎患者的影像学资料,所有患者在术前或保守治疗... 目的评估MR扩散峰度成像(diffusion kurtosis imaging,DKI)及扩散张量成像(diffusion-tensor imaging,DTI)在鉴别低级别胶质瘤与脑炎中的价值。材料与方法回顾性分析58例低级别胶质瘤或脑炎患者的影像学资料,所有患者在术前或保守治疗前均行MRI常规序列及DKI序列扫描。用NeuDiLab软件处理DKI图像,获得基于DKI模型的平均峰度(mean kurtosis,MK)、轴向扩散峰度(axial kurtosis,AK)和径向扩散峰度(radial kurtosis,RK)以及基于DTI模型的平均扩散系数(mean diffusivity,MD)、轴向扩散系数(axial diffusivity,AD)、径向扩散系数(radial diffusivity,RD)和各向异性分数(fractional anisotropy,FA)参数图及b=0 s/mm2的扩散图像(B0)。用ITK-SNAP软件在B0图像上手动勾画肿瘤的感兴趣容积(volume of interest,VOI),将其配准到其他参数图上。用FAE软件提取各参数图的平均值。根据病理检查或脑脊液检查结果将患者分为胶质瘤组和脑炎组。采用卡方检验、独立样本t检验及Mann-Whitney U检验比较两组患者的一般资料、常规MRI表现及扩散参数的差异。计算Cohen’s d值评估各扩散参数的效应量。绘制受试者工作特征(receiver operating characteristic,ROC)曲线,计算曲线下面积(area under the curve,AUC)、敏感度、特异度和准确度,并用De Long检验比较各参数的鉴别诊断效能。结果共51例患者被纳入研究,包括29例低级别胶质瘤患者、22例脑炎病变患者。RK鉴别诊断脑炎组低级别胶质瘤的表现最好,AUC为0.878,当阈值取0.662时,其敏感度为72.7%,特异度为89.7%。De Long检验显示DKI模型的诊断表现显著优于DTI模型。结论DKI序列有助于鉴别诊断低级别胶质瘤与脑炎。 展开更多
关键词 胶质瘤 脑炎 磁共振成像 扩散峰度成像 扩散张量成像
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A synthetic diagnostics platform for microwave imaging diagnostics in tokamaks
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作者 李子涵 杨尚川 +5 位作者 徐新航 张立夫 渠承明 李诚普 庄革 谢锦林 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期38-45,共8页
Interpreting experimental diagnostics data in tokamaks,while considering non-ideal effects,is challenging due to the complexity of plasmas.To address this challenge,a general synthetic diagnostics(GSD)platform has bee... Interpreting experimental diagnostics data in tokamaks,while considering non-ideal effects,is challenging due to the complexity of plasmas.To address this challenge,a general synthetic diagnostics(GSD)platform has been established that facilitates microwave imaging reflectometry and electron cyclotron emission imaging.This platform utilizes plasma profiles as input and incorporates the finite-difference time domain,ray tracing and the radiative transfer equation to calculate the propagation of plasma spontaneous radiation and the external electromagnetic field in plasmas.Benchmark tests for classical cases have been conducted to verify the accuracy of every core module in the GSD platform.Finally,2D imaging of a typical electron temperature distribution is reproduced by this platform and the results are consistent with the given real experimental data.This platform also has the potential to be extended to 3D electromagnetic field simulations and other microwave diagnostics such as cross-polarization scattering. 展开更多
关键词 synthetic diagnostics tokamak plasmas microwave imaging diagnostics microwave imaging reflectometer electron cyclotron emission imaging
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Self-confocal NIR-II fluorescence microscopy for multifunctional in vivo imaging
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作者 Jing Zhou Tianxiang Wu +5 位作者 Runze Chen Liang Zhu Hequn Zhang Yifei Li Liying Chen Jun Qian 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期105-119,共15页
Fluorescence imaging in the second near-infrared window(NIR-II,900–1880 nm)with less scattering background in biological tissues has been combined with the confocal microscopic system for achieving deep in vivo imagi... Fluorescence imaging in the second near-infrared window(NIR-II,900–1880 nm)with less scattering background in biological tissues has been combined with the confocal microscopic system for achieving deep in vivo imaging with high spatial resolution.However,the traditional NIR-IIfluorescence confocal microscope with separate excitation focus and detection pinhole makes it possess low confocal e±ciency,as well as di±cultly to adjust.Two types of upgraded NIR-IIfluorescence confocal microscopes,sharing the same pinhole by excitation and emission focus,leading to higher confocal e±ciency,are built in this work.One type is-ber-pinhole-based confocal microscope applicable to CW laser excitation.It is constructed forfluorescence intensity imaging with large depth,high stabilization and low cost,which could replace multiphotonfluorescence microscopy in some applications(e.g.,cerebrovascular and hepatocellular imaging).The other type is air-pinhole-based confocal microscope applicable to femtosecond(fs)laser excitation.It can be employed not only for NIR-IIfluorescence intensity imaging,but also for multi-channelfluorescence lifetime imaging to recognize different structures with similarfluorescence spectrum.Moreover,it can be facilely combined with multiphotonfluorescence microscopy.A single fs pulsed laser is utilized to achieve up-conversion(visible multiphotonfluorescence)and down-conversion(NIR-II one-photonfluorescence)excitation simultaneously,extending imaging spectral channels,and thus facilitates multi-structure and multi-functional observation. 展开更多
关键词 Self-confocal fiber-pinhole air-pinhole multi-channe fluorescence lifetime imaging multi-color imaging
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Performance optimization of the neutron-sensitive image intensifier used in neutron imaging
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作者 谭金昊 宋玉收 +14 位作者 周健荣 杨文钦 蒋兴奋 刘杰 张超月 周晓娟 夏远光 刘术林 闫保军 刘辉 王松林 赵豫斌 庄建 孙志嘉 陈元柏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期380-387,共8页
As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive ima... As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future. 展开更多
关键词 neutron detector neutron imaging microchannel plate image intensifier
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Microwave-induced thermoacoustic elastic imaging:A simulation study
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作者 Lin Huang Zheng Liang +1 位作者 Shuaiqi Qiao Weipeng Wang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期1-11,共11页
Microwave-induced thermoacoustic imaging(MTI)has the advantages of high resolution,high contrast,non-ionization,and non-invasive.Recently,MTI was used in the¯eld of breast cancer screening.In this paper,based on ... Microwave-induced thermoacoustic imaging(MTI)has the advantages of high resolution,high contrast,non-ionization,and non-invasive.Recently,MTI was used in the¯eld of breast cancer screening.In this paper,based on the¯nite element method(FEM)and COMSOL Multiphysics software,a three-dimensional breast cancer model suitable for exploring the MTI process is proposed to investigate the in°uence of Young's modulus(YM)of breast cancer tissue on MTI.It is found that the process of electromagnetic heating and initial pressure generation of the entire breast tissue is earlier in time than the thermal expansion process.Besides,compared with normal breast tissue,tumor tissue has a greater temperature rise,displacement,and pressure rise.In particular,YM of the tumor is related to the speed of thermal expansion.In particular,the larger the YM of the tumor is,the higher the heating and contraction frequency is,and the greater the maximum pressure is.Di®erent Young's moduli correspond to di®erent thermoacoustic signal spectra.In MTI,this study can be used to judge di®erent degrees of breast cancer based on elastic imaging.In addition,this study is helpful in exploring the possibility of microwave-induced thermoacoustic elastic imaging(MTAE). 展开更多
关键词 Thermoacoustic imaging breast cancer multi-physics simulation elastic imaging
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Development and prospect of acoustic reflection imaging logging processing and interpretation method
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作者 LI Ning LIU Peng +5 位作者 WU Hongliang LI Yusheng ZHANG Wenhao WANG Kewen FENG Zhou WANG Hao 《Petroleum Exploration and Development》 SCIE 2024年第4期839-851,共13页
Acoustic reflection imaging logging technology can detect and evaluate the development of reflection anomalies,such as fractures,caves and faults,within a range of tens of meters from the wellbore,greatly expanding th... Acoustic reflection imaging logging technology can detect and evaluate the development of reflection anomalies,such as fractures,caves and faults,within a range of tens of meters from the wellbore,greatly expanding the application scope of well logging technology.This article reviews the development history of the technology and focuses on introducing key methods,software,and on-site applications of acoustic reflection imaging logging technology.Based on the analyses of major challenges faced by existing technologies,and in conjunction with the practical production requirements of oilfields,the further development directions of acoustic reflection imaging logging are proposed.Following the current approach that utilizes the reflection coefficients,derived from the computation of acoustic slowness and density,to perform seismic inversion constrained by well logging,the next frontier is to directly establish the forward and inverse relationships between the downhole measured reflection waves and the surface seismic reflection waves.It is essential to advance research in imaging of fractures within shale reservoirs,the assessment of hydraulic fracturing effectiveness,the study of geosteering while drilling,and the innovation in instruments of acoustic reflection imaging logging technology. 展开更多
关键词 acoustic reflection imaging monopole P-waves dipole S-waves horizontal well acoustic reflection imaging 3D imaging well logging-seismic integration CIFLog software
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Topic highlight on texture and color enhancement imaging in gastrointestinal diseases
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作者 Osamu Toyoshima Toshihiro Nishizawa Keisuke Hata 《World Journal of Gastroenterology》 SCIE CAS 2024年第14期1934-1940,共7页
Olympus Corporation developed texture and color enhancement imaging(TXI)as a novel image-enhancing endoscopic technique.This topic highlights a series of hot-topic articles that investigated the efficacy of TXI for ga... Olympus Corporation developed texture and color enhancement imaging(TXI)as a novel image-enhancing endoscopic technique.This topic highlights a series of hot-topic articles that investigated the efficacy of TXI for gastrointestinal disease identification in the clinical setting.A randomized controlled trial demonstrated improvements in the colorectal adenoma detection rate(ADR)and the mean number of adenomas per procedure(MAP)of TXI compared with those of white-light imaging(WLI)observation(58.7%vs 42.7%,adjusted relative risk 1.35,95%CI:1.17-1.56;1.36 vs 0.89,adjusted incident risk ratio 1.48,95%CI:1.22-1.80,respectively).A cross-over study also showed that the colorectal MAP and ADR in TXI were higher than those in WLI(1.5 vs 1.0,adjusted odds ratio 1.4,95%CI:1.2-1.6;58.2%vs 46.8%,1.5,1.0-2.3,respectively).A randomized controlled trial demonstrated non-inferiority of TXI to narrow-band imaging in the colorectal mean number of adenomas and sessile serrated lesions per procedure(0.29 vs 0.30,difference for non-inferiority-0.01,95%CI:-0.10 to 0.08).A cohort study found that scoring for ulcerative colitis severity using TXI could predict relapse of ulcerative colitis.A cross-sectional study found that TXI improved the gastric cancer detection rate compared to WLI(0.71%vs 0.29%).A cross-sectional study revealed that the sensitivity and accuracy for active Helicobacter pylori gastritis in TXI were higher than those of WLI(69.2%vs 52.5%and 85.3%vs 78.7%,res-pectively).In conclusion,TXI can improve gastrointestinal lesion detection and qualitative diagnosis.Therefore,further studies on the efficacy of TXI in clinical practice are required. 展开更多
关键词 Endoscopy Texture and color enhancement imaging White-light imaging Narrow-band imaging Colorectal neoplasm Gastric cancer Adenoma Ulcerative colitis Helicobacter infections Colonoscopy
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Efficient single-pixel imaging encrypted transmission based on 3D Arnold transformation
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作者 梁振宇 王朝瑾 +4 位作者 王阳阳 高皓琪 朱东涛 许颢砾 杨星 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期378-386,共9页
Single-pixel imaging(SPI)can transform 2D or 3D image data into 1D light signals,which offers promising prospects for image compression and transmission.However,during data communication these light signals in public ... Single-pixel imaging(SPI)can transform 2D or 3D image data into 1D light signals,which offers promising prospects for image compression and transmission.However,during data communication these light signals in public channels will easily draw the attention of eavesdroppers.Here,we introduce an efficient encryption method for SPI data transmission that uses the 3D Arnold transformation to directly disrupt 1D single-pixel light signals and utilizes the elliptic curve encryption algorithm for key transmission.This encryption scheme immediately employs Hadamard patterns to illuminate the scene and then utilizes the 3D Arnold transformation to permutate the 1D light signal of single-pixel detection.Then the transformation parameters serve as the secret key,while the security of key exchange is guaranteed by an elliptic curve-based key exchange mechanism.Compared with existing encryption schemes,both computer simulations and optical experiments have been conducted to demonstrate that the proposed technique not only enhances the security of encryption but also eliminates the need for complicated pattern scrambling rules.Additionally,this approach solves the problem of secure key transmission,thus ensuring the security of information and the quality of the decrypted images. 展开更多
关键词 single-pixel imaging 3D Arnold transformation elliptic curve encryption image encryption
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Five-view three-dimensional reconstructionfor ultrafast dynamic imaging of pulsedradiation sources
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作者 Jianpeng Gao Liang Sheng +6 位作者 Xinyi Wang Yanhong Zhang Liang Li Baojun Duan Mei Zhang Yang Li Dongwei Hei 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期63-73,共11页
Multiaxial neutron/x-ray imaging and three-dimensional (3D) reconstruction techniques play a crucial role in gaining valuable insights intothe generation and evolution mechanisms of pulsed radiation sources. Owing to ... Multiaxial neutron/x-ray imaging and three-dimensional (3D) reconstruction techniques play a crucial role in gaining valuable insights intothe generation and evolution mechanisms of pulsed radiation sources. Owing to the short emission time (∼200 ns) and drastic changes of thepulsed radiation source, it is necessary to acquire projection data within a few nanoseconds in order to achieve clear computed tomography3D imaging. As a consequence, projection data that can be used for computed tomography image reconstruction at a certain moment are oftenavailable for only a few angles. Traditional algorithms employed in the process of reconstructing 3D images with extremely incomplete datamay introduce significant distortions and artifacts into the final image. In this paper, we propose an iterative image reconstruction methodusing cylindrical harmonic decomposition and a self-supervised denoising network algorithm based on the deep image prior method. Weaugment the prior information with a 2D total variation prior and a 3D deep image prior. Single-wire Z-pinch imaging experiments have beencarried out at Qin-1 facility in five views and four frames, with a time resolution of 3 ns for each frame and a time interval of 40 ns betweenadjacent frames. Both numerical simulations and experiments verify that our proposed algorithm can achieve high-quality reconstructionresults and obtain the 3D intensity distribution and evolution of extreme ultraviolet and soft x-ray emission from plasma. 展开更多
关键词 FRAMES image SOURCES
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