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Three-dimensional mapping and comparative analysis of the distal human corpus cavernosum and the inflatable penile prosthesis
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作者 Tariq S Hakky Daniel Ferguson +3 位作者 Philippe E Spiess Paul Bradley Tom FLue Rafael E Carrion 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第4期567-570,I0012,共5页
The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts an... The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts and compare them with 3D images of two prototypes of penile prosthesis. Two different models of the Titan Coloplast inflatable penile prosthesis were analyzed using a 3D scanner. The first was the standard model and the second was a newer model with a rounder silicone tip. Two cadaveric phalluses were harvested using Smooth-Cast 300Q polyurethane molding. The molds were excised and scanned along side the penile prosthesis. 3D scans were completed and analyzed using Leios Mesh software, and GOM Inspect software. The 3D scans demonstrated the mean human corporal radii 2 mm from the distal tip to be 36.51 mm (36.01-37.0 mm), which is an obtuse angle. The standard Titan penile prosthesis spherical radius at the same level was 202.52 mm, while the new silicone tip prosthesis had a radius of 139.33 mm. 3D mapping further demonstrated the trajectory of the cavernosa appeared curvilinear and the distal ends appeared blunt. The use of cadaveric cavernosal molds in combination with the 3D scanner allowed us to accurately image the corpus cavernosum for the first time. Our findings suggest that anatomically accurate corporal tips appear to be relatively blunt and that the new Titan silicone tip penile prosthesis more closely resembles the human corporal tip. 展开更多
关键词 corpus cavernosum penile prosthesis three-dimensional analysis
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Left Bundle Branch Ablation Guided by a Three-Dimensional Mapping System: A Novel Method for Establishing a Heart Failure Animal Model
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作者 Pengkang He Han Jin +3 位作者 Yiran Hu Sixian Weng Sijing Cheng Hao Huang 《Cardiovascular Innovations and Applications》 2023年第1期574-580,共7页
Objective:Few studies have been conducted to establish animal models of left bundle branch block by using three-dimensional mapping systems.This research was aimed at creating a canine left bundle branch block model b... Objective:Few studies have been conducted to establish animal models of left bundle branch block by using three-dimensional mapping systems.This research was aimed at creating a canine left bundle branch block model by using a three-dimensional mapping system.Materials and Methods:We used a three-dimensional mapping system to map and ablate the left bundle branch in beagles.Results:Ten canines underwent radiofrequency ablation,among which left bundle branch block was successfully es-tablished in eight,one experienced ventricular fibrillation,and one developed third-degree atrioventricular block.The maximum HV interval measured within the left ventricle was 29.00±2.93 ms,and the LBP-V interval at the ablation site was 20.63±2.77 ms.The LBP-V interval at the ablation target was 71.08%of the maximum HV interval.Conclusion:This three-dimensional mapping system is a reliable and effective guide for ablation of the left bundle branch in dogs. 展开更多
关键词 left bundle branch block heart failure animal model canine three-dimensional mapping ablation
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A human-machine interaction method for rock discontinuities mapping by three-dimensional point clouds with noises
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作者 Qian Chen Yunfeng Ge +3 位作者 Changdong Li Huiming Tang Geng Liu Weixiang Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1646-1663,共18页
Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results ca... Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results cannot be fed back to users timely.To address this issue,we proposed a human-machine interaction(HMI)method for discontinuity mapping.Users can help the algorithm identify the noise and make real-time result judgments and parameter adjustments.For this,a regular cube was selected to illustrate the workflows:(1)point cloud was acquired using remote sensing;(2)the HMI method was employed to select reference points and angle thresholds to detect group discontinuity;(3)individual discontinuities were extracted from the group discontinuity using a density-based cluster algorithm;and(4)the orientation of each discontinuity was measured based on a plane fitting algorithm.The method was applied to a well-studied highway road cut and a complex natural slope.The consistency of the computational results with field measurements demonstrates its good accuracy,and the average error in the dip direction and dip angle for both cases was less than 3.Finally,the computational time of the proposed method was compared with two other popular algorithms,and the reduction in computational time by tens of times proves its high computational efficiency.This method provides geologists and geological engineers with a new idea to map rapidly and accurately rock structures under large amounts of noises or unclear features. 展开更多
关键词 Rock discontinuities three-dimensional(3D)point clouds Discontinuity identification Orientation measurement Human-machine interaction
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A physics-informed machine learning solution for landslide susceptibility mapping based on three-dimensional slope stability evaluation
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作者 WANG Yun-hao WANG Lu-qi +4 位作者 ZHANG Wen-gang LIU Song-lin SUN Wei-xin HONG Li ZHU Zheng-wei 《Journal of Central South University》 CSCD 2024年第11期3838-3853,共16页
Landslide susceptibility mapping is a crucial tool for disaster prevention and management.The performance of conventional data-driven model is greatly influenced by the quality of the samples data.The random selection... Landslide susceptibility mapping is a crucial tool for disaster prevention and management.The performance of conventional data-driven model is greatly influenced by the quality of the samples data.The random selection of negative samples results in the lack of interpretability throughout the assessment process.To address this limitation and construct a high-quality negative samples database,this study introduces a physics-informed machine learning approach,combining the random forest model with Scoops 3D,to optimize the negative samples selection strategy and assess the landslide susceptibility of the study area.The Scoops 3D is employed to determine the factor of safety value leveraging Bishop’s simplified method.Instead of conventional random selection,negative samples are extracted from the areas with a high factor of safety value.Subsequently,the results of conventional random forest model and physics-informed data-driven model are analyzed and discussed,focusing on model performance and prediction uncertainty.In comparison to conventional methods,the physics-informed model,set with a safety area threshold of 3,demonstrates a noteworthy improvement in the mean AUC value by 36.7%,coupled with a reduced prediction uncertainty.It is evident that the determination of the safety area threshold exerts an impact on both prediction uncertainty and model performance. 展开更多
关键词 machine learning physics-informed model negative samples selection INTERPRETABILITY landslide susceptibility mapping
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心脏磁共振T1 mapping在心肌病的应用及成像技术进展
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作者 邓佳 唐惠芳 +4 位作者 周宏 余莹 杨雯敏 周锦标 田进伟 《中国动脉硬化杂志》 2025年第2期154-162,共9页
随着心脏磁共振成像技术的不断发展,T1 mapping可以无创性、可视化和定量地评估心脏疾病的心肌纤维化、水肿和浸润性。应用T1 mapping评估心肌疾病的局限性和弥漫性心肌纤维化,在疾病的诊断、鉴别、治疗和预后风险评估中发挥了重要的临... 随着心脏磁共振成像技术的不断发展,T1 mapping可以无创性、可视化和定量地评估心脏疾病的心肌纤维化、水肿和浸润性。应用T1 mapping评估心肌疾病的局限性和弥漫性心肌纤维化,在疾病的诊断、鉴别、治疗和预后风险评估中发挥了重要的临床作用。本文旨在全面介绍T1 mapping在心肌病患者中的临床应用,归纳常用的扫描技术及其成像原理。 展开更多
关键词 心脏磁共振 T1 mapping 心肌病
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Fine mapping of Pm71,a novel powdery mildew resistance gene from emmer wheat 被引量:2
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作者 Jiadong Zhang Hong Yang +10 位作者 Guohao Han Hongxing Xu Ruishan Liu Ningning Yu Ran Han Yaoxue Li Jiatong Li Yintao Dai Cheng Liu Yuli Jin Pengtao Ma 《The Crop Journal》 2025年第1期62-68,共7页
Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage... Powdery mildew negatively impacts wheat yield and quality.Emmer wheat(Triticum dicoccum),an ancestral species of common wheat,is a gene donor for wheat improvement.Cultivated emmer accession H1-707 exhibited all-stage resistance to powdery mildew over consecutive years.Genetic analysis of H1-707 at the seedling stage revealed a dominant monogenic inheritance pattern,and the underlying gene was designated Pm71.By employing bulked segregant exome sequencing(BSE-Seq)and using 2000 F2:3 families,Pm71 was fine mapped to a 336-kb interval on chromosome arm 6AS by referencing to the durum cv.Svevo RefSeq 1.0.Collinearity analysis revealed high homology in the candidate interval between Svevo and six Triticum species.Among six high-confidence genes annotated within this interval,TRITD6Av1G005050 encoding a GDSL esterase/lipase was identified as a key candidate for Pm71. 展开更多
关键词 Blumeria graminis BSE-Seq Disease resistance Fine mapping Triticum dicoccum
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基于T2^(*)mapping的业余马拉松运动员足踝部关节软骨损伤及其影响因素分析
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作者 高雅丽 兰晓川 +2 位作者 王舒 宋凌恒 陈伟 《磁共振成像》 北大核心 2025年第2期94-99,共6页
目的基于T2^(*)mapping定量分析业余马拉松运动员足踝部关节软骨的T2^(*)值,并分析其与性别、年龄、身体质量指数(body mass index,BMI)、跑龄、跑量之间的相关性。材料与方法于2023年7月份至2023年9月份招募重庆市长跑运动爱好者48名,... 目的基于T2^(*)mapping定量分析业余马拉松运动员足踝部关节软骨的T2^(*)值,并分析其与性别、年龄、身体质量指数(body mass index,BMI)、跑龄、跑量之间的相关性。材料与方法于2023年7月份至2023年9月份招募重庆市长跑运动爱好者48名,其中跑量<300 km/月的36例(中低跑量组),跑量≥300 km/月的12例(高跑量组)。所有受试者均进行单侧无症状踝关节的MRI扫描,扫描序列包括T2^(*)mapping多回波自旋回波(spin echo,SE)序列矢状位、质子密度加权成像脂肪抑制(proton density-weighted imaging fat-saturated,PDWI-FS)序列矢状位、冠状位、横轴位以及T1加权脂肪抑制成像(T1-weighted imaging fat-saturated,T1WI-FS)序列横轴位。沿关节软骨轮廓边缘勾画距骨穹窿、跟骰关节跟骨面、骰骨面及后距下关节跟骨面、距骨面软骨作为感兴趣区(region of interest,ROI),获得相应的T2^(*)值。采用线性回归分析软骨T2^(*)值与年龄、BMI、跑龄的相关性,采用独立样本t检验分析不同跑量及不同性别间的软骨T2^(*)值差异。结果(1)距骨穹窿、跟骰关节跟骨面及骰骨面、后距下关节跟骨面及距骨面软骨T2^(*)值在性别上的差异均具有统计学意义(P=0.001、P<0.001、P=0.002、P=0.008、P=0.004);(2)高跑量组的距骨穹窿、后距下关节跟骨面软骨T2^(*)值高于中低跑量组(P=0.014、0.023),不同跑量的跟骰关节跟骨面及骰骨面、后距下关节距骨面软骨T2^(*)值的差异均无统计学意义(P=0.987、0.072、0.724);(3)距骨穹窿、跟骰关节跟骨面及骰骨面、后距下关节跟骨面、距骨面软骨T2^(*)值均与BMI呈正相关(r=0.376、0.384、0.300、0.422、0.455,P=0.005、0.004、0.019、0.001、0.001)。结论在业余马拉松运动员这一跑步群体中,与中低跑量相比,高跑量更有可能导致距骨穹窿、后距下关节跟骨面软骨损伤;而与较低的BMI相比,高BMI增加了距骨穹窿、跟骰关节跟骨面、骰骨面及后距下关节跟骨面、距骨面软骨损伤的风险。 展开更多
关键词 业余马拉松 跑步 软骨 磁共振成像 T2^(*)mapping
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Three-dimensional models:from cell culture to Patient-Derived Organoid and its application to future liposarcoma research
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作者 SAYUMI TAHARA SYDNEY RENTSCH +4 位作者 FERNANDA COSTAS CASAL DE FARIA PATRICIA SARCHET ROMA KARNA FEDERICA CALORE RAPHAEL E.POLLOCK 《Oncology Research》 SCIE 2025年第1期1-13,共13页
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ... Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma. 展开更多
关键词 Cell culture LIPOSARCOMA Patient-Derived Organoid(PDO) SPHEROID three-dimensional(3D)cell culture
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models
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作者 Duc-Dam Nguyen Nguyen Viet Tiep +5 位作者 Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期467-500,共34页
This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble lear... This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and AB-RBFN.Additionally,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and validation.The models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to roads.These factors were instrumental in predicting the output variable,which was the probability of landslide occurrence.Statistical analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other models.The AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of 0.926.These results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making. 展开更多
关键词 Landslide susceptibility map spatial analysis ensemble modelling information values(IV)
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Constructing, Mapping, and Analyzing Global Urban Forest Databases Using Hyperlinks: A World of Vast Unevenness and Research Challenges
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作者 Stanley D. Brunn Olena Dronova Mahmuda Sharmin 《Natural Resources》 2025年第1期1-23,共23页
A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking an... A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking and policies related to human/environmental worlds at local, regional, and global scales. Maps are an important part of these innovative and ongoing research approaches. In this context, we consider urban forests a topic meriting more attention of scholars studying the geographic and environmental intersections of the natural sciences with the social sciences and humanities. We construct two innovative knowledge bases, one a conceptual framework based on major themes and concepts related to mapping urban forests using key words of the first 100 results of a Google Scholar query and a second using the number of Google Scholar hyperlinks about mapping urban forests in 244 capital cities. We discovered that the constructed world maps reveal vast global unevenness in our knowledge about urban forests in hyperlink numbers and ratios, results that merit further attention by disciplinary, international and interdisciplinary scholarly communities. 展开更多
关键词 Urban Forests Database mapping Google Scholar HYPERLINKS DISPARITIES Unevenness
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A Review of Three-Dimensional Research on Urban Recreation Space Based on CiteSpace
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作者 LIU Yongli 《Journal of Landscape Research》 2025年第1期30-34,共5页
In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring t... In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring the scientific development trend and research hotspots in this field.The results show that the number of published documents shows a fluctuating upward trend,and the significant growth rate reflects the role of policy orientation in promoting the concept of compact city.The co-occurrence analysis of keywords reveals the research hotspots of“compact city”,“recreation space”and“urban park”,while the emergence of new keywords such as“vertical city”and“spatial justice”indicates the new trend of recent research.The cluster analysis and timeline map further show the evolution of research themes,with“compact city”being the largest cluster and having rich connections with other themes such as“urban design”and“urban park”. 展开更多
关键词 Compact city Urban recreation space three-dimensional CITESPACE
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T2 mapping不同测量方法在甲状腺相关眼病活动性评估中的应用
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作者 信雨晴 潘富强 +2 位作者 王亚磊 袁玉山 张杨 《中国CT和MRI杂志》 2025年第2期71-73,共3页
目的分析T2 mapping不同感兴趣区(ROI)勾画方法在甲状腺相关眼病(TAO)活动分期中的应用价值。方法27例患者的53个眼眶纳入研究,行3.0T MR冠状位T2 mapping扫描,采用临床活动性评分(CAS)进行分期,通过三种勾画方法获得T2HS(在炎症受累最... 目的分析T2 mapping不同感兴趣区(ROI)勾画方法在甲状腺相关眼病(TAO)活动分期中的应用价值。方法27例患者的53个眼眶纳入研究,行3.0T MR冠状位T2 mapping扫描,采用临床活动性评分(CAS)进行分期,通过三种勾画方法获得T2HS(在炎症受累最重眼肌的信号较高区域勾画小的ROI,记为热点)、T2SS(单只眼肌热点层面的均值)及T2SO(单侧眼眶四条眼肌肌腹层面的均值),分析三者与CAS的相关性及其诊断效能。结果活动期T2HS、T2SS和T2SO均高于非活动期。三者均与CAS正相关,T2SO相关性最强(r=0.606,P<0.0001)。ROC曲线显示三者对TAO活动性分期均有一定的诊断效能,虽然结果显示T2SS诊断效能较优,AUC=0.833,截断值94.25ms时判断活动性敏感度为68%,特异度为91%,但Delong检验提示三者差异无统计学意义。结论T2 mapping序列的三种测量方法均可用于TAO的活动性评估,综合分析,T2SS较适合用于分期。 展开更多
关键词 GRAVES眼病 T2 mapping 磁共振成像 感兴趣区 活动性分期 动眼肌
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Three-dimensional reconstruction under computed tomography and myopectineal orifice measurement under laparoscopy for quality control of inguinal hernia treatment
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作者 Lei Zhang Jing Chen +7 位作者 Yu-Ying Zhang Lei Liu Han-Dan Wang Ya-Fei Zhang Jun Sheng Qiu-Shi Hu Ming-Liang Liu Yi-Lin Yuan 《World Journal of Gastrointestinal Endoscopy》 2025年第3期50-59,共10页
BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are ne... BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are necessary.However,due to differences in race and sex,people’s body shapes vary.According to European guidelines,the patch should measure 10 cm×15 cm.If any part of the MPO is dissected,injury to the nerves,vascular network,or organs may occur during surgery,thereby leading to inguinal discomfort,pain,and seroma formation after surgery.Therefore,accurate localization and measurement of the boundary of the MPO are crucial for selecting the optimal patch for inguinal hernia repair.AIM To compare the size of the MPO measured on three-dimensional multislice spiral computed tomography(CT)with that measured via laparoscopy and explore the relevant factors influencing the size of the MPO.METHODS Clinical data from 74 patients who underwent laparoscopic tension-free inguinal hernia repair at the General Surgery Department of the First Affiliated Hospital of Anhui University of Science and Technology between September 2022 and July 2024 were collected and analyzed retrospectively.Transabdominal preperitoneal was performed.Sixty-four males and 10 females,with an average age of 58.30±12.32 years,were included.The clinical data of the patients were collected.The boundary of the MPO was measured on three-dimensional CT images before surgery and then again during transabdominal preperitoneal.All the preoperative and intraoperative data were analyzed via paired t-tests.A t-test was used for comparisons of age,body mass index,and sex between the groups.In the comparative analysis,a P value less than 0.05 indicated a significant difference.RESULTS The boundaries of the MPO on 3-dimensional CT images measured 7.05±0.47 cm and 6.27±0.61 cm,and the area of the MPO was 19.54±3.33 cm^(2).The boundaries of the MPO during surgery were 7.18±0.51 cm and 6.17±0.40 cm.The errors were not statistically significant.However,the intraoperative BD(the width of the MPO,P=0.024,P<0.05)and preoperative AC(the length of the MPO,P=0.045,P<0.05)significantly differed according to sex.The AC and BD measurements before and during surgery were not significantly different according to age,body mass index,hernia side or hernia type(P>0.05).CONCLUSION The application of this technology can aid in determining the most appropriate dissection range and patch size. 展开更多
关键词 HERNIA INGUINAL Myopectineal orifice three-dimensional reconstruction Computed tomography Inguinal hernia
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磁共振联合T2-mapping对电针治疗腰椎间盘突出症中短期疗效评价的价值分析
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作者 朱薇萍 吕莹 +2 位作者 徐婷 戴德纯 屠建春 《上海针灸杂志》 2025年第3期290-295,共6页
目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LD... 目的通过磁共振(magnetic resonance,MR)常规序列联合T2-mapping观察电针治疗腰椎间盘突出症(lumbar disc herniation,LDH)后有效及无效患者,探讨其在电针治疗LDH中短期疗效评价中的价值。方法随机选择经电针治疗后判定为有效和无效的LDH患者各32例,分别设为A组和B组。两组治疗前后分别记录腰椎日本骨科协会(Japanese Orthopaedic Association,JOA)评估治疗分数、Oswestry功能障碍指数(Oswestry disability index,ODI)评分,进行腰椎MR扫描并测量突出椎间盘髓核T2值和突出部分面积。两组均对治疗后JOA改善率及治疗前T2值、突出面积进行相关性分析,并比较治疗后及随访时T2值和突出面积。结果A组治疗前、治疗后及随访时突出椎间盘髓核T2值均明显高于B组(P<0.05);A组治疗1个疗程后突出部分面积明显小于B组(P<0.05)。A组治疗后JOA评分改善率与治疗前突出椎间盘髓核T2值具有中度相关关系(P<0.05),与突出部分面积未见有线性相关关系(P>0.05)。结论通过MR常规序列联合T2-mapping观察突出椎间盘髓核T2值,在电针治疗LDH中短期疗效评价中存在一定的临床价值,其或可为成为LDH保守治疗方案选择的辅助指标之一。 展开更多
关键词 针刺疗法 腰椎间盘突出症 电针 T2-mapping T2值
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A general methodological framework for hazard assessment in remote mountain areas combining geomorphological mapping with UAV survey
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作者 Elena GAROVA Bogdan CHADROMTSEV +6 位作者 Alexander PEDANOV Pavel GREBENNIKOV Igor ILTUGANOV Pavel LOBANOV Pavel PONOMARJOVS Felix DRAESNER Sven FUCHS 《Journal of Mountain Science》 2025年第3期763-775,共13页
This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing... This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing techniques and is adaptable to different national standards,thus ensuring its applicability in a variety of contexts.The principal objective is to guarantee the safety of mountainous regions,particularly in the vicinity of essential infrastructure,where the scope for implementing structural measures is restricted.The framework commences with comprehensive geomorphological mapping,which facilitates the identification of past hazardous processes and potential future hazards.New technologies,such as uncrewed aerial vehicles(UAVs),are employed to create high-resolution DEMs,which are particularly beneficial in regions with limited data availability.These models facilitate the assessment of potential hazards and inform decisions regarding protective measures.The utilisation of UAVs enhances the accuracy and efficiency of data collection,particularly in remote mountainous regions where alternative remotely sensed information may be unavailable.The integration of modern approaches into traditional hazard assessment methods allows for a comprehensive analysis of the spatial distribution of factors driving mass wasting processes.This workflow provides valuable insights that assist in the prioritisation of interventions and the optimisation of risk reduction in high mountainous areas. 展开更多
关键词 Geomorphological mapping Hazard assessment UAV Remote mountain areas Mitigation planning
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联合T_(1)-Mapping与T_(2)-Mapping评估慢性肾病肾功能的价值
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作者 李雪松 张庆娟 +2 位作者 余玉盛 周清清 张宏 《医学影像学杂志》 2025年第2期84-87,99,共5页
目的探讨联合T_(1)-Mapping与T_(2)-Mapping评估慢性肾病(CKD)肾功能的可行性。方法选取CKD患者81例,所有患者均行T_(2)WI、T_(1)-Mapping及T_(2)-Mapping扫描及肾功能生化检查。基于估算肾小球滤过率(eGFR)将患者分为轻、中及重度三组... 目的探讨联合T_(1)-Mapping与T_(2)-Mapping评估慢性肾病(CKD)肾功能的可行性。方法选取CKD患者81例,所有患者均行T_(2)WI、T_(1)-Mapping及T_(2)-Mapping扫描及肾功能生化检查。基于估算肾小球滤过率(eGFR)将患者分为轻、中及重度三组,测量肾脏T_(1)及T_(2)值并比较其组间差异及与eGFR的相关性。结果三组间肾皮质、髓质T_(1)值及髓质T_(2)值差异有统计学意义(F=8.353,9.431,10.090;P<0.05)。肾皮质T_(1)值、髓质T_(1)值及髓质T_(2)与eGFR存在相关性(r=-0.409,-0.389,0.372;P<0.05)。联合肾皮质、髓质T_(1)值及髓质T_(2)值在鉴别轻度与中、重度CKD的诊断效能最佳(AUC=0.869,P<0.001)。结论T_(1)-Mapping与T_(2)-Mapping对CKD肾功能评估具有一定参考价值;联合T_(1)-Mapping与T_(2)-Mapping可提高鉴别轻度与中、重度CKD的诊断效能。 展开更多
关键词 慢性肾病 肾功能评估 磁共振成像 定量技术
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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions
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作者 Chentong GAO Huiyu SUN +1 位作者 Jianping GU W.M.HUANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期123-138,共16页
Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade compone... Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade components.In this paper,a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established.Based on Kirchhoff's plate assumptions,the displacement variables of the plate are expressed.By incorporating the braiding directions into the constitutive equation of the braided composites,the dynamic model of the plate considering braiding directions is obtained.The effects of the speeds,braiding directions,and braided angles on the responses of the plate with fixed-axis rotation and translational motion,respectively,are investigated.This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions.It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications. 展开更多
关键词 three-dimensional(3D)braided composite braiding direction composite thin plate large overall motion dynamic model
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Research on three-dimensional attack area based on improved backtracking and ALPS-GP algorithms of air-to-air missile
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作者 ZHANG Haodi WANG Yuhui HE Jiale 《Journal of Systems Engineering and Electronics》 2025年第1期292-310,共19页
In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of t... In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of the three-dimensional attack area model,restrict their practical applications.To address these issues,an improved backtracking algorithm is proposed to improve calculation efficiency.A significant reduction in solution time and maintenance of accuracy in the three-dimensional attack area are achieved by using the proposed algorithm.Furthermore,the age-layered population structure genetic programming(ALPS-GP)algorithm is introduced to determine an analytical polynomial model of the three-dimensional attack area,considering real-time requirements.The accuracy of the polynomial model is enhanced through the coefficient correction using an improved gradient descent algorithm.The study reveals a remarkable combination of high accuracy and efficient real-time computation,with a mean error of 91.89 m using the analytical polynomial model of the three-dimensional attack area solved in just 10^(-4)s,thus meeting the requirements of real-time combat scenarios. 展开更多
关键词 air combat three-dimensional attack area improved backtracking algorithm age-layered population structure genetic programming(ALPS-GP) gradient descent algorithm
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Attitude control of flexible satellite via three-dimensional magnetically suspended wheel
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作者 J.TAYEBI Yingjie CHEN +1 位作者 Ti CHEN Shiyuan JIA 《Applied Mathematics and Mechanics(English Edition)》 2025年第3期555-572,共18页
This paper proposes an attitude control strategy for a flexible satellite equipped with an orthogonal cluster of three-dimensional(3D)magnetically suspended wheels(MSWs).The mathematical model for the satellite incorp... This paper proposes an attitude control strategy for a flexible satellite equipped with an orthogonal cluster of three-dimensional(3D)magnetically suspended wheels(MSWs).The mathematical model for the satellite incorporating flexible appendages and an orthogonal cluster of magnetically suspended reaction wheel actuators is initially developed.After that,an adaptive attitude controller is designed with a switching surface of variable structure,an adaptive law for estimating inertia matrix uncertainty,and a fuzzy disturbance observer for estimating disturbance torques.Additionally,a Moore-Penrose-based steering law is proposed to derive the tilt angle commands of the orthogonal configuration of the 3D MSW to follow the designed control signal.Finally,numerical simulations are presented to validate the effectiveness of the proposed control strategy. 展开更多
关键词 flexible satellite three-dimensional(3D)magnetically suspended wheel(MSW) attitude control adaptive control disturbance observer
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Beyond the Hertzsprung-Russell Diagram: An Enhanced Three-Dimensional Model Unveiling the Multidimensional Cosmos of Stars
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作者 Rohan Kumar 《Journal of Applied Mathematics and Physics》 2025年第2期575-592,共18页
Despite its utility in identifying patterns in celestial objects, the Hertzsprung-Russell diagram is not supported in dim or small stars;it struggles to provide insights into certain celestial objects such as brown dw... Despite its utility in identifying patterns in celestial objects, the Hertzsprung-Russell diagram is not supported in dim or small stars;it struggles to provide insights into certain celestial objects such as brown dwarfs [1]. The purpose of this experiment is to create an improved version of the diagram with a three-dimensional model that includes a third z-axis to accurately predict and chart the life cycles of all stars regardless of size. The values of the stars’ absolute magnitude and color indices were used to chart the surface gravity and metallicity, variables that were chosen due to their ease of collection and their likeliness to be within the range of values being assessed. To obtain the values for the model, data points from the database GAIA DR2 were utilized via the TAP protocol to query the SQL database. The data was transferred into a local CSV file to facilitate data manipulation. The data could be read and interpreted, as dim stars would likely have higher values of these variables, making it easier to include them in the diagram. The Pandas DataFrames tool on Python 3 was used to organize and manage the data efficiently. Matplotlib Graphs visualized the relationships between different stellar attributes by developing a linear regression line and an algorithm and creating scatter plots and sky maps to explore trends, hence designing three-dimensional diagrams. It was determined that the surface gravity diagram had a higher efficacy than metallicity due to their standard deviations of 0.4641441715272741 and 0.786577627976148, respectively. 展开更多
关键词 Color-Magnitude Diagram Main Sequence METALLICITY Spectral Energy Distribution Diagram Surface Gravity three-dimensional Stellar Evolution Models Luminosity in Low-Mass Stars
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