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Inter-Observer Variability in the Interpretation of 68Ga-PSMA PET-CT Scan according to PROMISE Criteria
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作者 Amina Nasir Muhammad Numair Younis +3 位作者 Sadia Adnan Tahira Yasmin Ismat Fatima Abubaker Shahid 《Advances in Molecular Imaging》 2022年第1期1-13,共13页
Aims & Objectives: Aim of the study was to evaluate inter-observer variability in interpretation of Gallium-68 labeled Prostate Specific Membrane Antigen sub-type 11 (68Ga-PSMA-11) Positron Emission Tomography-Com... Aims & Objectives: Aim of the study was to evaluate inter-observer variability in interpretation of Gallium-68 labeled Prostate Specific Membrane Antigen sub-type 11 (68Ga-PSMA-11) Positron Emission Tomography-Computed Tomography PET_CT scan according to Prostate Cancer Molecular Imaging Standardized Evaluation (PROMISE) criteria. Method and Materials: Forty-four consecutive patients of prostate cancer were prospectively studied between the duration of January 2021 to June 2021 at Institute of Nuclear Medicine and Oncology (INMOL), Lahore. All PET-CT scans were assessed by a researcher and 3 nuclear physicians and divided into two groups, interpreted in two phases. In the first phase, each group independently evaluated the scans while in the second phase, a consensus meeting was held and all the cases with discordance were discussed. Cohen’s Kappa test was used to measure interobserver variability with the cut-off of K’s alpha Results: The study showed 41 out of 44 scans with positive PSMA findings while 03 scans were negative for any PSMA avid disease. In the first phase of image analysis, the level of agreement was slight in T stage (Kappa = 0.068, p = 0.65), moderate in the miN stage (Kappa = 0.46, p = 0.02) and substantial in miM stage (Kappa = 0.77, p ≤ 0.001) was seen. For PSMA score, overall agreement was substantial agreement (Kappa = 0.64, p Conclusion: Remarkable inter-observer agreement was seen in PROMISE criteria. 展开更多
关键词 68Ga-PSMA pet-ct PROMISE Criteria PSMA Score Inter-Observer Variability
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^(18)F-FDG PET-CT联合MRI对于前列腺癌的临床诊断价值
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作者 孙鹤云 杜菲雨 +2 位作者 何光远 许梦苗 范光磊 《中国医药指南》 2024年第5期40-43,共4页
目的探讨^(18)F-FDG PET-CT联合MRI在前列腺癌诊断及分期中的应用价值。方法选取我院2020年8月—2023年8月期间收治的70例疑似前列腺癌患者为研究对象,纳入患者均接受PET-CT及MRI检查,以病理穿刺活检结果作为诊断金标准,评价二者联合诊... 目的探讨^(18)F-FDG PET-CT联合MRI在前列腺癌诊断及分期中的应用价值。方法选取我院2020年8月—2023年8月期间收治的70例疑似前列腺癌患者为研究对象,纳入患者均接受PET-CT及MRI检查,以病理穿刺活检结果作为诊断金标准,评价二者联合诊断的诊断效能。结果70例疑似前列腺癌患者,经过穿刺活检确诊为前列腺癌50例,前列腺良性病变20例;其中MRI诊断出前列腺癌43例,前列腺良性病变27例;PET-CT诊断出前列腺癌48例,前列腺良性病变23例;PET-CT+MRI诊断出前列腺癌51例,前列腺良性病变19例;PET-CT联合MRI诊断的准确度、敏感度高于单一诊断,漏诊率低于单一诊断(P<0.05),而二者联合诊断前列腺癌的特异度及误诊率无统计学差异(P>0.05)。病理分期诊断上,50例经病理活检确诊为前列腺癌的患者,低分化腺癌13例;T期40例(T1~T2期11例,T3期22例,T4期7例),N期10例;对于前列腺癌T分期评价,PET-CT+MRI检查的准确度高于单一检查(P<0.05)。结论PET-CT联合MRI相比二者任一检查对前列腺癌及其病理分期具有较高的诊断效能,可减少漏诊率及误诊率。 展开更多
关键词 ^(18)氟-氟脱氧葡萄糖 pet-ct MRI 前列腺癌
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护理干预对PET-CT图像质量与心理状态的影响分析
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作者 张辉 赵辉 《中文科技期刊数据库(引文版)医药卫生》 2024年第9期0122-0125,共4页
PET-CT检查患者,制定常规及个性化护理方案,以图像质量、心理状态评价。方法 为探索护理对PET-CT影响,以两种方案对120例患者干预,形成A组(常规护理60例)、B组(常规+个体化护理60例),评价效果差异。结果 两组焦虑评分、图像主观质量评... PET-CT检查患者,制定常规及个性化护理方案,以图像质量、心理状态评价。方法 为探索护理对PET-CT影响,以两种方案对120例患者干预,形成A组(常规护理60例)、B组(常规+个体化护理60例),评价效果差异。结果 两组焦虑评分、图像主观质量评分、一次检查成功率、护理满意度,均以B组更优(P<0.05)。结论 PET-CT检查中,护理干预尤为关键,方案选择以个体化护理更优,可满足情绪管理、图像质量管理、一次检查成功率需求,并提升护理满意度。 展开更多
关键词 pet-ct 护理干预 图像质量
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规范化流程管理在非小细胞肺癌患者PET-CT检查中的应用效果
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作者 宁静 陈辉 姚志华 《黑龙江医学》 2024年第2期185-187,191,共4页
目的:探讨规范化流程管理在非小细胞肺癌患者PET-CT检查中的应用效果,为确保临床非小细胞肺癌的诊疗质量提供参考依据。方法:选取2019年3月—2021年10月河南省肿瘤医院收治的112例非小细胞肺癌患者作为研究对象,按照随机数表法分组,患... 目的:探讨规范化流程管理在非小细胞肺癌患者PET-CT检查中的应用效果,为确保临床非小细胞肺癌的诊疗质量提供参考依据。方法:选取2019年3月—2021年10月河南省肿瘤医院收治的112例非小细胞肺癌患者作为研究对象,按照随机数表法分组,患者均接受PET-CT检查,且检查期间,予以对照组(56例)患者原工作流程操作,予以观察组(56例)患者规范化流程管理,比较两组患者图像合格率、检查前准备完好率、检查时准备完好率、检测的等待时间和检查时间,干预前后焦虑、抑郁情绪评分,以及患者对护理工作的满意度。结果:观察组患者检查前准备完好率、检查时准备完好率高于对照组,差异有统计学意义(χ^(2)=5.617、1.734,P<0.05),同时观察组患者检测的等待时间和检查时间均较对照组缩短,差异有统计学意义(t=5.469、4.941,P<0.05)。与干预前比,干预后两组患者情绪焦虑自评量表(SAS)、抑郁自评量表(SDS)评分降低,且试验组患者低于对照组,差异有统计学意义(t=11.298、8.414,P<0.05)。观察组患者对护理工作的满意度高于对照组,差异有统计学意义(χ^(2)=4.350,P<0.05)。结论:非小细胞肺癌患者PET-CT检查中应用规范化流程管理可缩短患者的检查等待和检查时间,提升诊疗效率,并取得良好的图像质量,患者对护理工作的满意度高。 展开更多
关键词 非小细胞肺癌 规范化流程管理 pet-ct检查 图像质量 满意度
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基于肿瘤形状特征与点云方法的PET-CT多模态图像神经母细胞瘤分割
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作者 周维钦 王朝立 +4 位作者 孙占全 陈素芸 李超 傅宏亮 刘晓虹 《软件导刊》 2024年第3期128-133,共6页
通过智能学习方法对PET-CT图像进行肿瘤自动分割,是辅助医生制定诊疗计划的重要研究领域。PET-CT图像兼具PET和CT两种模态优点,传统方法大多只简单的将两种模态的图像进行配准和融合后提取特征,忽略了神经母细胞瘤具有肿瘤边界轮廓不规... 通过智能学习方法对PET-CT图像进行肿瘤自动分割,是辅助医生制定诊疗计划的重要研究领域。PET-CT图像兼具PET和CT两种模态优点,传统方法大多只简单的将两种模态的图像进行配准和融合后提取特征,忽略了神经母细胞瘤具有肿瘤边界轮廓不规则的特点。为此,提出一种两阶段的自动分割框架结构模型。首先,利用3D卷积神经网络定位肿瘤位置;然后在分割出的肿瘤区域附近生成多模态点云数据,并提取肿瘤的形状轮廓特征;最后,将两个网络提取的特征进行融合用来预测最终分割结果。在自有数据集和公共数据集上,将所提模型与其他多模态方法进行比较实验,实验结果验证了所提模型的优越性与有效性。以期为研究神经母细胞瘤分割的研究人员提供参考与借鉴。 展开更多
关键词 深度学习 点云 多模态 医学图像分割 pet-ct
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A landslide monitoring method using data from unmanned aerial vehicle and terrestrial laser scanning with insufficient and inaccurate ground control points 被引量:1
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作者 Jiawen Zhou Nan Jiang +1 位作者 Congjiang Li Haibo Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4125-4140,共16页
Non-contact remote sensing techniques,such as terrestrial laser scanning(TLS)and unmanned aerial vehicle(UAV)photogrammetry,have been globally applied for landslide monitoring in high and steep mountainous areas.These... Non-contact remote sensing techniques,such as terrestrial laser scanning(TLS)and unmanned aerial vehicle(UAV)photogrammetry,have been globally applied for landslide monitoring in high and steep mountainous areas.These techniques acquire terrain data and enable ground deformation monitoring.However,practical application of these technologies still faces many difficulties due to complex terrain,limited access and dense vegetation.For instance,monitoring high and steep slopes can obstruct the TLS sightline,and the accuracy of the UAV model may be compromised by absence of ground control points(GCPs).This paper proposes a TLS-and UAV-based method for monitoring landslide deformation in high mountain valleys using traditional real-time kinematics(RTK)-based control points(RCPs),low-precision TLS-based control points(TCPs)and assumed control points(ACPs)to achieve high-precision surface deformation analysis under obstructed vision and impassable conditions.The effects of GCP accuracy,GCP quantity and automatic tie point(ATP)quantity on the accuracy of UAV modeling and surface deformation analysis were comprehensively analyzed.The results show that,the proposed method allows for the monitoring accuracy of landslides to exceed the accuracy of the GCPs themselves by adding additional low-accuracy GCPs.The proposed method was implemented for monitoring the Xinhua landslide in Baoxing County,China,and was validated against data from multiple sources. 展开更多
关键词 Landslide monitoring Data fusion Terrestrial laser scanning(TLS) Unmanned aerial vehicle(UAV) Model reconstruction
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PET-CT及CT增强联合诊断肝脏黏液性囊性肿瘤伴全身多发转移一例 被引量:1
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作者 胡艳丽 周怡 +3 位作者 邓辉 周鹏 金文义 王燕 《罕少疾病杂志》 2024年第5期10-11,共2页
1病例资料男,32岁。一周前因爬山不慎摔倒,怀疑骨折入院检查。外院CT、MRI检查示全身多发骨质破坏,提示骨转移瘤,为明确原发病灶行PET-CT检查。影像学表现:全身PET-CT显示全身多发骨质破坏(颅骨、多发椎体、双侧肱骨、双侧锁骨、双肩胛... 1病例资料男,32岁。一周前因爬山不慎摔倒,怀疑骨折入院检查。外院CT、MRI检查示全身多发骨质破坏,提示骨转移瘤,为明确原发病灶行PET-CT检查。影像学表现:全身PET-CT显示全身多发骨质破坏(颅骨、多发椎体、双侧肱骨、双侧锁骨、双肩胛骨、胸骨、多发肋骨、骨盆骨、双股骨),放射性摄取明显增高;肝尾状叶囊实性占位伴肝门、腹膜后多发淋巴结肿大,放射性摄取增高。 展开更多
关键词 肝脏 黏液性囊性肿瘤 pet-ct MSCT
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双探针PET-CT在阿尔茨海默病中的临床应用价值
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作者 娜姿·伊力哈木 张奇洲 +1 位作者 秦永德 李肖红 《中国老年学杂志》 CAS 北大核心 2024年第6期1355-1359,共5页
目的 探讨双探针PET-CT在阿尔茨海默病(AD)中的临床应用价值。方法 回顾性纳入确诊AD患者(AD组)14例,健康对照者(HC组)8例。均行^(18)F-氟脱氧葡萄糖(FDG)正电子发射型计算机断层显像(PET-CT)脑部显像,1 w内行^(18)F-氟贝他吡(AV45)脑... 目的 探讨双探针PET-CT在阿尔茨海默病(AD)中的临床应用价值。方法 回顾性纳入确诊AD患者(AD组)14例,健康对照者(HC组)8例。均行^(18)F-氟脱氧葡萄糖(FDG)正电子发射型计算机断层显像(PET-CT)脑部显像,1 w内行^(18)F-氟贝他吡(AV45)脑部显像。通过半定量法分析两种示踪剂在AD组中的分布特点。结果 两组空腹葡萄糖水平、三酰甘油(TG)、简易智力状态检查(MMSE)及蒙特利尔认知评估(MoCA)量表评分均有统计学差异(均P<0.05);相关性分析表明,空腹葡萄糖水平、TG、MMSE及MoCA评分均与AD存在显著相关性(P<0.05)。两组^(18)F-FDG SUVR值在额叶、顶叶、楔前叶、后扣带回、颞叶及枕叶有统计学差异(P<0.05);^(18)F-AV45 SUVR值在额叶、顶叶、楔前叶、后扣带回、颞叶、枕叶及基底节均有统计学差异(P<0.05)。AD组^(18)F-FDG在各脑区的SUVR值与^(18)F-AV45在各脑区的SUVR值均无相关性(P>0.05)。结论 联合两种分子探针在AD早期诊断中具有较高的价值。 展开更多
关键词 阿尔茨海默病 β淀粉样蛋白 ^(18)F-氟贝他吡(AV45) ^(18)F-氟脱氧葡萄糖(FDG) 正电子发射型计算机断层显像(pet-ct)
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Acousto-optic scanning multi-photon lithography with high printing rate
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作者 Minghui Hong 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期1-3,共3页
As a manufacturing method that is focused on end-users,3D printing has gained a lot of attention in recent years due to its unique advantages in fabricating complex three-dimensional structures.Various new micro-nano ... As a manufacturing method that is focused on end-users,3D printing has gained a lot of attention in recent years due to its unique advantages in fabricating complex three-dimensional structures.Various new micro-nano 3D printing methods have been developed to meet the demand for high-precision and high-yield manufacturing1-9.Among them,multi-photon-photon lithography(MPL) is a promising 3D nanofabrication technology due to its capability of true 3D digital processing and nanoscale processing resolution beyond the diffraction limit.It has been widely used to fabricate microoptics10,11,photonic crystals12,microfluidics13,meta-surfaces14,and mechanical metamaterials15. 展开更多
关键词 PHOTON Acous scanNING
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Ultrasound Scanning Competencies in Midwifery Education in Zambia: Findings from a Desk Review and Needs Assessment
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作者 Mutinke Zulu Sebean Mayimbo Patricia Katowa-Mukwato 《Health》 2024年第6期535-552,共18页
Introduction: Ultrasound is an essential component of antenatal care. Midwives provide most of the antenatal care but they do not perform ultrasound as it has been beyond their scope of practice. This leaves many wome... Introduction: Ultrasound is an essential component of antenatal care. Midwives provide most of the antenatal care but they do not perform ultrasound as it has been beyond their scope of practice. This leaves many women in Low and Middle-Income Countries without access to ultrasound scanning. The aim of this study was to identify competencies in ultrasound scanning in midwifery education. Methods: A desk review and needs assessment were conducted between July and October 2023. Articles and curricula on the internet, Google scholar and PubMed were searched for content on ultrasound scanning competencies. A Google form consisting of 20 questions was administered via email and WhatsApp to 135 participants. Descriptive statistics were used to analyse data. Results: The desk review showed that it is feasible to train midwives in ultrasound scanning. The training programs for midwives in obstetric ultrasound were conducted for 1 week to 3 months with most of them running for 4 weeks. Content included introduction to general principles of ultrasound, physics, basic knowledge in embryology, obstetrics, anatomy, measuring foetal biometry, estimating amniotic fluid and gestational age. Experts like sonographers trained midwives. Theory and hands on were the teaching methods used. Written and practical assessments were conducted. Needs assessment revealed that majority of participants 71 (53%) knew about basic ultrasound training for midwives. All participants (100%) said it is necessary to train midwives in basic ultrasound scan in Zambia. Some content should include, anatomy, measuring foetal biometry, assessing amniotic fluid level, and gestational age determination. Most participants 91 (67%) suggested that the appropriate duration of training is 4 - 6 weeks. Conclusion: Empowering every midwife with ultrasound scanning skills will enable early detection of any abnormality among pregnant women and prompt intervention to save lives. 展开更多
关键词 Ultrasound scanning Midwifery Education Competencies
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Investigation of reflection anisotropy induced by micropipe defects on the surface of a 4H-SiC single crystal using scanning anisotropy microscopy
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作者 黄威 俞金玲 +7 位作者 刘雨 彭燕 王利军 梁平 陈堂胜 徐现刚 刘峰奇 陈涌海 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期630-637,共8页
Optical reflection anisotropy microscopy mappings of micropipe defects on the surface of a 4H-SiC single crystal are studied by the scanning anisotropy microscopy(SAM)system.The reflection anisotropy(RA)image with a&#... Optical reflection anisotropy microscopy mappings of micropipe defects on the surface of a 4H-SiC single crystal are studied by the scanning anisotropy microscopy(SAM)system.The reflection anisotropy(RA)image with a'butterfly pattern'is obtained around the micropipes by SAM.The RA image of the edge dislocations is theoretically simulated based on dislocation theory and the photoelastic principle.By comparing with the Raman spectrum,it is verified that the micropipes consist of edge dislocations.The different patterns of the RA images are due to the different orientations of the Burgers vectors.Besides,the strain distribution of the micropipes is also deduced.One can identify the dislocation type,the direction of the Burgers vector and the optical anisotropy from the RA image by using SAM.Therefore,SAM is an ideal tool to measure the optical anisotropy induced by the strain field around a defect. 展开更多
关键词 scanning anisotropy microscopy SiC reflection anisotropy edge dislocation
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Prophylactic Pattern Scanning Laser Retinal Photocoagulation for Diabetic Retinopathy in Spontaneously Diabetic Torii Fatty Rats: Preliminary Experimental Results
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作者 Rina Takagi Yoshiaki Tanaka +6 位作者 Tetsuya Hasegawa Masami Shinohara Yasushi Kageyama Tomohiko Sasase Machiko Shimmura-Tomita Akihiro Kakehashi Toshikatsu Kaburaki 《Journal of Diabetes Mellitus》 CAS 2024年第3期153-165,共13页
Research Background and Purpose: The number of diabetic patients is rapidly increasing, making it crucial to find methods to prevent diabetic retinopathy (DR), a leading cause of blindness. We investigated the effects... Research Background and Purpose: The number of diabetic patients is rapidly increasing, making it crucial to find methods to prevent diabetic retinopathy (DR), a leading cause of blindness. We investigated the effects of prophylactic pattern scanning laser retinal photocoagulation on DR development in Spontaneously Diabetic Torii (SDT) fatty rats as a new prevention approach. Methods: Photocoagulation was applied to the right eyes of 8-week-old Spontaneously Diabetic Torii (SDT) fatty rats, with the left eyes serving as untreated controls. Electroretinography at 9 and 39 weeks of age and pathological examinations, including immunohistochemistry for vascular endothelial growth factor and glial fibrillary acidic protein at 24 and 40 weeks of age, were performed on both eyes. Results: There were no significant differences in amplitude and prolongation of the OP waves between the right and left eyes in SDT fatty rats at 39 weeks of age. Similarly, no significant differences in pathology and immunohistochemistry were observed between the right and left eyes in SDT fatty rats at 24 and 40 weeks of age. Conclusion: Prophylactic pattern scanning retinal laser photocoagulation did not affect the development of diabetic retinopathy in SDT fatty rats. 展开更多
关键词 Diabetes Pattern scanning Laser Diabetic Retinopathy Spontaneously Diabetic Torii Fatty Rats ELECTRORETINOGRAPHY
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Uniformity Control of Scanned Beam in 300 MeV Proton and Heavy Ion Accelerator Complex at SESRI
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作者 HOU Lingxiao YUAN Youjin +10 位作者 SHEN Guodong RUAN Shuang LIU Jie ZHU Yunpeng WANG Geng GUO Hongliang LYU Mingbang GAO Daqing XU Zhiguo SHENG Lina YANG Jiancheng 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第4期705-713,共9页
In recent years,heavy ion accelerator technology has been rapidly developing worldwide and widely applied in the fields of space radiation simulation and particle therapy.Usually,a very high uniformity in the irradiat... In recent years,heavy ion accelerator technology has been rapidly developing worldwide and widely applied in the fields of space radiation simulation and particle therapy.Usually,a very high uniformity in the irradiation area is required for the extracted ion beams,which is crucial because it directly affects the experimental precision and therapeutic effect.Specifically,ultra-large-area and high-uniformity scanning are crucial requirements for spacecraft radiation effects assessment and serve as core specification for beamline terminal design.In the 300 MeV proton and heavy ion accelerator complex at the Space Environment Simulation and Research Infrastructure(SESRI),proton and heavy ion beams will be accelerated and ultimately delivered to three irradiation terminals.In order to achieve the required large irradiation area of 320 mm×320 mm,horizontal and vertical scanning magnets are used in the extraction beam line.However,considering the various requirements for beam species and energies,the tracking accuracy of power supplies(PSs),the eddy current effect of scanning magnets,and the fluctuation of ion bunch structure will reduce the irradiation uniformity.To mitigate these effects,a beam uniformity optimization method based on the measured beam distribution was proposed and applied in the accelerator complex at SESRI.In the experiment,the uniformity is successfully optimized from 75%to over 90%after five iterations of adjustment to the PS waveforms.In this paper,the method and experimental results were introduced. 展开更多
关键词 heavy ion accelerator beam uniformity scanning magnet MIC
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Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests
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作者 Frederico Tupinambá-Simões Adrián Pascual +3 位作者 Juan Guerra-Hernández Cristóbal Ordóñez Tiago de Conto Felipe Bravo 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期14-25,共12页
The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high resolution.To confirm the con-sistency in the retrieval of forest structural par... The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high resolution.To confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is crucial.We analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus pyrenaica.The area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning paths.Ground reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in phenology.Ninety-six percent of all pairs matched below 65 cm.For DBH,phenology barely altered estimates.We observed a strong agreement when comparing HLS-based tree height distributions.The values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous species.Tree volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions. 展开更多
关键词 Precision forestry Forest monitoring Mobile laser scanning Forest inventory
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A review of understanding electrocatalytic reactions in energy conversion and energy storage systems via scanning electrochemical microscopy
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作者 Jihye Park Jong Hwan Lim +4 位作者 Jin-Hyuk Kang Jiheon Lim Ho Won Jang Hosun Shin Sun Hwa Park 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期155-177,共23页
To address climate change and promote environmental sustainability,electrochemical energy conversion and storage systems emerge as promising alternative to fossil fuels,catering to the escalating demand for energy.Ach... To address climate change and promote environmental sustainability,electrochemical energy conversion and storage systems emerge as promising alternative to fossil fuels,catering to the escalating demand for energy.Achieving optimal energy efficiency and cost competitiveness in these systems requires the strategic design of electrocatalysts,coupled with a thorough comprehension of the underlying mechanisms and degradation behavior occurring during the electrocatalysis processes.Scanning electrochemical microscopy(SECM),an analytical technique for studying surface electrochemically,stands out as a powerful tool offering electrochemical insights.It possesses remarkable spatiotemporal resolution,enabling the visualization of the localized electrochemical activity and surface topography.This review compiles crucial research findings and recent breakthroughs in electrocatalytic processes utilizing the SECM methodology,specifically focusing on applications in electrolysis,fuel cells,and metal–oxygen batteries within the realm of energy conversion and storage systems.Commencing with an overview of each energy system,the review introduces the fundamental principles of SECM,and aiming to provide new perspectives and broadening the scope of applied research by describing the major research categories within SECM. 展开更多
关键词 scanning electrochemical microscopy ELECTROCATALYST ELECTROCATALYSIS Water splitting Fuel cell Metal-oxygen battery
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Imaging of human parafoveal area with large field of view in adaptive optics line scanning ophthalmoscope
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作者 Wen Kong Yiwei Chen +1 位作者 Guohua Shi Yi He 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第6期41-51,共11页
The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological changes.The current adaptive optics scanning l... The parafoveal area,with its high concentration of photoreceptors andfine retinal capillaries,is crucial for central vision and often exhibits early signs of pathological changes.The current adaptive optics scanning laser ophthalmoscope(AOSLO)provides an excellent tool to acquire accurate and detailed information about the parafoveal area with cellular resolution.However,limited by the scanning speed of two-dimensional scanning,thefield of view(FOV)in the AOSLO system was usually less than or equal to 2,and the stitching for the parafoveal area required dozens of images,which was time-consuming and laborious.Unfortunately,almost half of patients are unable to obtain stitched images because of their poorfixation.To solve this problem,we integrate AO technology with the line-scan imaging method to build an adaptive optics line scanning ophthalmoscope(AOLSO)system with a larger FOV.In the AOLSO,afocal spherical mirrors in pairs are nonplanar arranged and the distance and angle between optical elements are optimized to minimize the aberrations,two cylinder lenses are orthogonally placed before the imaging sensor to stretch the point spread function(PSF)for sufficiently digitizing light energy.Captured human retinal images show the whole parafoveal area with 55FOV,60 Hz frame rate and cellular resolutions.Take advantage of the 5FOV of the AOLSO,only 9 frames of the retina are captured with several minutes to stitch a montage image with an FOV of 99,in which photoreceptor counting is performed within approximately 5eccentricity.The AOLSO system not only provides cellular resolution but also has the capability to capture the parafoveal region in a single frame,which offers great potential for noninvasive studying of the parafoveal area. 展开更多
关键词 Adaptive optics line scanning retinal imaging system parafoveal capillary vasculature.
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Influence of pore structure heterogeneity on channeling channels during hot water flooding in heavy oil reservoir based on CT scanning
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作者 Qing-Jun Du Hao-Yu Zheng +3 位作者 Jian Hou Yong-Ge Liu Jian-Fang Sun Dong Zhao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2407-2419,共13页
Hot water flooding is an effective way to develop heavy oil reservoirs.However,local channeling channels may form,possibly leading to a low thermal utilization efficiency and high water cut in the reservoir.The pore s... Hot water flooding is an effective way to develop heavy oil reservoirs.However,local channeling channels may form,possibly leading to a low thermal utilization efficiency and high water cut in the reservoir.The pore structure heterogeneity is an important factor in forming these channels.This study proposes a method that mixes quartz sand with different particle sizes to prepare weakly heterogeneous and strongly heterogeneous models through which hot water flooding experiments are conducted.During the experiments,computer tomography(CT)scanning identifies the pore structure and micro remaining oil saturation distribution to analyze the influence of the pore structure heterogeneity on the channeling channels.The oil saturation reduction and average pore size are divided into three levels to quantitatively describe the relationship between the channeling channel distribution and pore structure heterogeneity.The zone where oil saturation reduction exceeds 20%is defined as a channeling channel.The scanning area is divided into 180 equally sized zones based on the CT scanning images,and threedimensional(3D)distributions of the channeling channels are developed.Four micro remaining oil distribution patterns are proposed,and the morphology characteristics of micro remaining oil inside and outside the channeling channels are analyzed.The results show that hot water flooding is more balanced in the weakly heterogeneous model,and the oil saturation decreases by more than 20%in most zones without narrow channeling channels forming.In the strongly heterogeneous model,hot water flooding is unbalanced,and three narrow channeling channels of different lengths form.In the weakly heterogeneous model,the oil saturation reduction is greater in zones with larger pores.The distribution range of the average pore size is larger in the strongly heterogeneous model.The network remaining oil inside the channeling channels is less than outside the channeling channels,and the hot water converts the network remaining oil into cluster,film,and droplet remaining oil. 展开更多
关键词 Heavy oil Hot water flooding Pore structure Channeling channels CT scanning
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Fatigue properties and damage constitutive model of salt rock based on CT scanning
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作者 Junbao Wang Xiao Liu +3 位作者 Qiang Zhang Xinrong Liu Zhanping Song Shijin Feng 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期245-259,共15页
To investigate the macroscopic fatigue properties and the mesoscopic pore evolution characteristics of salt rock under cyclic loading,fatigue tests under different upper-limit stresses were carried out on salt rock,an... To investigate the macroscopic fatigue properties and the mesoscopic pore evolution characteristics of salt rock under cyclic loading,fatigue tests under different upper-limit stresses were carried out on salt rock,and the mesoscopic pore structures of salt rock before and after fatigue tests and under different cycle numbers were measured using CT scanning instrument.Based on the test results,the effects of the cycle number and the upper-limit stress on the evolution of cracks,pore morphology,pore number,pore volume,pore size,plane porosity,and volume porosity of salt rock were analyzed.The failure path of salt rock specimens under cyclic loading was analyzed using the distribution law of plane porosity.The damage variable of salt rock under cyclic loading was defined on basis of the variation of volume porosity with cycle number.In order to describe the fatigue deformation behavior of salt rock under cyclic loading,the nonlinear Burgers damage constitutive model was further established.The results show that the model established can better reflect the whole development process of fatigue deformation of salt rock under cyclic loading. 展开更多
关键词 Salt rock Cyclic loading CT scanning Mesoscopic pore evolution Constitutive model
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Assessing the dynamics of O_(2) desorption from cobalt phthalocyanine by in situ electrochemical scanning tunneling microscopy
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作者 Yu-Qi Wang Yue Feng +1 位作者 Xiang Wang Dong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期144-148,共5页
We report here the in situ electrochemical scanning tunneling microscopy(ECSTM) study of cobalt phthalocyanine(CoPc)-catalyzed O_(2) evolution reaction(OER) and the dynamics of CoPc-O_(2) dissociation.The self-assembl... We report here the in situ electrochemical scanning tunneling microscopy(ECSTM) study of cobalt phthalocyanine(CoPc)-catalyzed O_(2) evolution reaction(OER) and the dynamics of CoPc-O_(2) dissociation.The self-assembled CoPc monolayer is fabricated on Au(111) substrate and resolved by ECSTM in 0.1 M KOH electrolyte.The OH^(-)adsorption on CoPc prior to OER is observed in ECSTM images.During OER,the generated O_(2) adsorbed on Co Pc is observed in the CoPc monolayer.Potential step experiment is employed to monitor the desorption of OER-generated O_(2) from CoPc,which results in the decreasing surface coverage of CoPc-O_(2) with time.The rate constant of O_(2) desorption is evaluated through data fitting.The insights into the dynamics of Co-O_(2) dissociation at the molecular level via in situ imaging help understand the role of Co-O_(2) in oxygen reduction reaction(ORR) and OER. 展开更多
关键词 Electrochemical scanning tunneling microscopy Oxygen evolution reaction Cobalt phthalocyanine
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Study on Joint Method of 3D Acoustic Emission Source Localization Simplex and Grid Search Scanning
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作者 Liu Wei-jian Wang Hao-nan +4 位作者 Xiao Yang Hou Meng-jie Dong Sen-sen Zhang Zhi-zeng Lu Gao-ming 《Applied Geophysics》 SCIE CSCD 2024年第3期456-467,617,共13页
Acoustic emission(AE)source localization is a fundamental element of rock fracture damage imaging.To improve the efficiency and accuracy of AE source localization,this paper proposes a joint method comprising a three-... Acoustic emission(AE)source localization is a fundamental element of rock fracture damage imaging.To improve the efficiency and accuracy of AE source localization,this paper proposes a joint method comprising a three-dimensional(3D)AE source localization simplex method and grid search scanning.Using the concept of the geometry of simplexes,tetrahedral iterations were first conducted to narrow down the suspected source region.This is followed by a process of meshing the region and node searching to scan for optimal solutions,until the source location is determined.The resulting algorithm was tested using the artificial excitation source localization and uniaxial compression tests,after which the localization results were compared with the simplex and exhaustive methods.The results revealed that the localization obtained using the proposed method is more stable and can be effectively avoided compared with the simplex localization method.Furthermore,compared with the global scanning method,the proposed method is more efficient,with an average time of 10%–20%of the global scanning localization algorithm.Thus,the proposed algorithm is of great significance for laboratory research focused on locating rupture damages sustained by large-sized rock masses or test blocks. 展开更多
关键词 acoustic emission simplex form grid search scan locating the epicenter
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