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Precision organoid segmentation technique(POST):accurate organoid segmentation in challenging bright-field images 被引量:1
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作者 Xuan Du Yuchen Li +5 位作者 Jiaping Song Zilin Zhang Jing Zhang Yanhui Li Zaozao Chen Zhongze Gu 《Bio-Design and Manufacturing》 2026年第1期80-93,I0013-I0016,共18页
Organoids possess immense potential for unraveling the intricate functions of human tissues and facilitating preclinical disease treatment.Their applications span from high-throughput drug screening to the modeling of... Organoids possess immense potential for unraveling the intricate functions of human tissues and facilitating preclinical disease treatment.Their applications span from high-throughput drug screening to the modeling of complex diseases,with some even achieving clinical translation.Changes in the overall size,shape,boundary,and other morphological features of organoids provide a noninvasive method for assessing organoid drug sensitivity.However,the precise segmentation of organoids in bright-field microscopy images is made difficult by the complexity of the organoid morphology and interference,including overlapping organoids,bubbles,dust particles,and cell fragments.This paper introduces the precision organoid segmentation technique(POST),which is a deep-learning algorithm for segmenting challenging organoids under simple bright-field imaging conditions.Unlike existing methods,POST accurately segments each organoid and eliminates various artifacts encountered during organoid culturing and imaging.Furthermore,it is sensitive to and aligns with measurements of organoid activity in drug sensitivity experiments.POST is expected to be a valuable tool for drug screening using organoids owing to its capability of automatically and rapidly eliminating interfering substances and thereby streamlining the organoid analysis and drug screening process. 展开更多
关键词 Organoid Drug screening Deep learning Image segmentation
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How precise is precise enough?Tree crown segmentation using high resolution close-up multispectral UAV images and its effect on NDVI accuracy in Fraxinus excelsior L.trees
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作者 Lisa Buchner Anna-Katharina Eisen Susanne Jochner-Oette 《Journal of Forestry Research》 2026年第2期16-30,共15页
Detailed individual tree crown segmentation is highly relevant for the detection and monitoring of Fraxinus excelsior L.trees affected by ash dieback,a major threat to common ash populations across Europe.In this stud... Detailed individual tree crown segmentation is highly relevant for the detection and monitoring of Fraxinus excelsior L.trees affected by ash dieback,a major threat to common ash populations across Europe.In this study,both fine and coarse crown segmentation methods were applied to close-range multispectral UAV imagery.The fine tree crown segmentation method utilized a novel unsupervised machine learning approach based on a blended NIR-NDVI image,whereas the coarse segmentation relied on the segment anything model(SAM).Both methods successfully delineated tree crown outlines,however,only the fine segmentation accurately captured internal canopy gaps.Despite these structural differences,mean NDVI values calculated per tree crown revealed no significant differences between the two approaches,indicating that coarse segmentation is sufficient for mean vegetation index assessments.Nevertheless,the fine segmentation revealed increased heterogeneity in NDVI values in more severely damaged trees,underscoring its value for detailed structural and health analyses.Furthermore,the fine segmentation workflow proved transferable to both individual UAV images and orthophotos from broader UAV surveys.For applications focused on structural integrity and spatial variation in canopy health,the fine segmentation approach is recommended. 展开更多
关键词 Leaf mass segmentation Machine learning segment anything model Ash dieback
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An intelligent segmentation method for leakage points in central serous chorioretinopathy based on fluorescein angiography images
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作者 Jian-Guo Xu Yong-Chi Liu +4 位作者 Fen Zhou Jian-Xin Shen Zhi-Peng Yan Xin-Ya Hu Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 2026年第3期421-433,共13页
AIM:To construct an intelligent segmentation scheme for precise localization of central serous chorioretinopathy(CSC)leakage points,thereby enabling ophthalmologists to deliver accurate laser treatment without navigat... AIM:To construct an intelligent segmentation scheme for precise localization of central serous chorioretinopathy(CSC)leakage points,thereby enabling ophthalmologists to deliver accurate laser treatment without navigational laser equipment.METHODS:A dataset with dual labels(point-level and pixel-level)was first established based on fundus fluorescein angiography(FFA)images of CSC and subsequently divided into training(102 images),validation(40 images),and test(40 images)datasets.An intelligent segmentation method was then developed,based on the You Only Look Once version 8 Pose Estimation(YOLOv8-Pose)model and segment anything model(SAM),to segment CSC leakage points.Next,the YOLOv8-Pose model was trained for 200 epochs,and the best-performing model was selected to form the optimal combination with SAM.Additionally,the classic five types of U-Net series models[i.e.,U-Net,recurrent residual U-Net(R2U-Net),attention U-Net(AttU-Net),recurrent residual attention U-Net(R2AttUNet),and nested U-Net(UNet^(++))]were initialized with three random seeds and trained for 200 epochs,resulting in a total of 15 baseline models for comparison.Finally,based on the metrics including Dice similarity coefficient(DICE),intersection over union(IoU),precision,recall,precisionrecall(PR)curve,and receiver operating characteristic(ROC)curve,the proposed method was compared with baseline models through quantitative and qualitative experiments for leakage point segmentation,thereby demonstrating its effectiveness.RESULTS:With the increase of training epochs,the mAP50-95,Recall,and precision of the YOLOv8-Pose model showed a significant increase and tended to stabilize,and it achieved a preliminary localization success rate of 90%(i.e.,36 images)for CSC leakage points in 40 test images.Using manually expert-annotated pixel-level labels as the ground truth,the proposed method achieved outcomes with a DICE of 57.13%,an IoU of 45.31%,a precision of 45.91%,a recall of 93.57%,an area under the PR curve(AUC-PR)of 0.78 and an area under the ROC curve(AUC-ROC)of 0.97,which enables more accurate segmentation of CSC leakage points.CONCLUSION:By combining the precise localization capability of the YOLOv8-Pose model with the robust and flexible segmentation ability of SAM,the proposed method not only demonstrates the effectiveness of the YOLOv8-Pose model in detecting keypoint coordinates of CSC leakage points from the perspective of application innovation but also establishes a novel approach for accurate segmentation of CSC leakage points through the“detect-then-segment”strategy,thereby providing a potential auxiliary means for the automatic and precise realtime localization of leakage points during traditional laser photocoagulation for CSC. 展开更多
关键词 You Only Look Once version 8 Pose Estimation segment anything model central serous chorioretinopathy leakage point segmentation
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Different approaches of laparoscopic anatomic hepatectomy of segment 7 for hepatocellular carcinoma:A multicenter study
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作者 Xing-Ru Wang Qi-Fan Zhang +6 位作者 Wei Cheng Xiao Liang Jun Cao Yong-Gang Wei Jian-Wei Li Hong-Guang Wang Chinese Research Group for Minimally Invasive Anatomical Liver Resection(The Workshop of Liver Future 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期42-51,共10页
Background:Laparoscopic anatomic hepatectomy of segment 7(LAH-S7)is a challenging surgery.In this study we aimed to investigate surgical and oncological outcomes of various approaches of LAH-S7 in patients with hepato... Background:Laparoscopic anatomic hepatectomy of segment 7(LAH-S7)is a challenging surgery.In this study we aimed to investigate surgical and oncological outcomes of various approaches of LAH-S7 in patients with hepatocellular carcinoma(HCC).A particular focus was placed on identifying the Glissonean pedicle of segment 7(G7)and the intersegmental plane.Given the scarcity of comprehensive reviews or comparative studies on clinical outcomes,we also sought to analyze the experiences and advantages associated with different approaches in relation to the anatomic variations of G7.Methods:The clinical data of 124 patients who underwent LAH-S7 for HCC across seven tertiary referral medical centers in China were retrospectively analyzed.Three surgical approaches were categorized based on the procedures used for G7 identification:the indocyanine green(ICG)fluorescence positive staining approach(IFPA),the Glissonean approach(GA),and the hepatic vein-guided approach(HVGA).Subsequently,the postoperative short-term results and oncological outcomes of the three different approaches were compared.Results:The distribution of surgical approaches among the patients was as follows:IFPA in 16(12.9%),GA in 62(50.0%),and HVGA in 46(37.1%)patients.Complications were observed in 27(21.8%)patients.The 1-,3-,and 5-year overall survival(OS)rates were 99.1%,89.2%,and 84.7%,respectively.The 1-,3-,and 5-year recurrence-free survival(RFS)rates were 99.0%,84.7%,and 69.3%,respectively.The OS and RFS rates were comparable across the three approaches.Conclusions:Following a standardized surgical procedure,LAH-S7 is demonstrated to be safe and yields favorable oncological outcomes.Surgeons performing LAH-S7 should select the appropriate surgical approach based on the anatomical characteristics and variations of G7. 展开更多
关键词 Hepatocellular carcinoma Liver neoplasms HEPATECTOMY LAPAROSCOPY Indocyanine green segment 7
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Enhanced BEV Scene Segmentation:De-Noise Channel Attention for Resource-Constrained Environments
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作者 Argho Dey Yunfei Yin +3 位作者 Zheng Yuan ZhiwenZeng Xianjian Bao Md Minhazul Islam 《Computers, Materials & Continua》 2026年第4期2161-2180,共20页
Autonomous vehicles rely heavily on accurate and efficient scene segmentation for safe navigation and efficient operations.Traditional Bird’s Eye View(BEV)methods on semantic scene segmentation,which leverage multimo... Autonomous vehicles rely heavily on accurate and efficient scene segmentation for safe navigation and efficient operations.Traditional Bird’s Eye View(BEV)methods on semantic scene segmentation,which leverage multimodal sensor fusion,often struggle with noisy data and demand high-performance GPUs,leading to sensor misalignment and performance degradation.This paper introduces an Enhanced Channel Attention BEV(ECABEV),a novel approach designed to address the challenges under insufficient GPU memory conditions.ECABEV integrates camera and radar data through a de-noise enhanced channel attention mechanism,which utilizes global average and max pooling to effectively filter out noise while preserving discriminative features.Furthermore,an improved fusion approach is proposed to efficiently merge categorical data across modalities.To reduce computational overhead,a bilinear interpolation layer normalizationmethod is devised to ensure spatial feature fidelity.Moreover,a scalable crossentropy loss function is further designed to handle the imbalanced classes with less computational efficiency sacrifice.Extensive experiments on the nuScenes dataset demonstrate that ECABEV achieves state-of-the-art performance with an IoU of 39.961,using a lightweight ViT-B/14 backbone and lower resolution(224×224).Our approach highlights its cost-effectiveness and practical applicability,even on low-end devices.The code is publicly available at:https://github.com/YYF-CQU/ECABEV.git. 展开更多
关键词 Autonomous vehicle BEV attention mechanism sensor fusion scene segmentation
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A Novel Semi-Supervised Multi-View Picture Fuzzy Clustering Approach for Enhanced Satellite Image Segmentation
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作者 Pham Huy Thong Hoang Thi Canh +2 位作者 Nguyen Tuan Huy Nguyen Long Giang Luong Thi Hong Lan 《Computers, Materials & Continua》 2026年第3期1092-1117,共26页
Satellite image segmentation plays a crucial role in remote sensing,supporting applications such as environmental monitoring,land use analysis,and disaster management.However,traditional segmentation methods often rel... Satellite image segmentation plays a crucial role in remote sensing,supporting applications such as environmental monitoring,land use analysis,and disaster management.However,traditional segmentation methods often rely on large amounts of labeled data,which are costly and time-consuming to obtain,especially in largescale or dynamic environments.To address this challenge,we propose the Semi-Supervised Multi-View Picture Fuzzy Clustering(SS-MPFC)algorithm,which improves segmentation accuracy and robustness,particularly in complex and uncertain remote sensing scenarios.SS-MPFC unifies three paradigms:semi-supervised learning,multi-view clustering,and picture fuzzy set theory.This integration allows the model to effectively utilize a small number of labeled samples,fuse complementary information from multiple data views,and handle the ambiguity and uncertainty inherent in satellite imagery.We design a novel objective function that jointly incorporates picture fuzzy membership functions across multiple views of the data,and embeds pairwise semi-supervised constraints(must-link and cannot-link)directly into the clustering process to enhance segmentation accuracy.Experiments conducted on several benchmark satellite datasets demonstrate that SS-MPFC significantly outperforms existing state-of-the-art methods in segmentation accuracy,noise robustness,and semantic interpretability.On the Augsburg dataset,SS-MPFC achieves a Purity of 0.8158 and an Accuracy of 0.6860,highlighting its outstanding robustness and efficiency.These results demonstrate that SSMPFC offers a scalable and effective solution for real-world satellite-based monitoring systems,particularly in scenarios where rapid annotation is infeasible,such as wildfire tracking,agricultural monitoring,and dynamic urban mapping. 展开更多
关键词 Multi-view clustering satellite image segmentation semi-supervised learning picture fuzzy sets remote sensing
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Probabilistic seismic hazard analysis for the northern segment of the North-South Seismic Belt in China based on improved spatial smoothing and fault source model integration
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作者 Yaohu Zhang Hua Pan +1 位作者 Meng Zhang Ying Shi 《Earthquake Science》 2026年第1期1-31,共31页
The northern segment of the North-South Seismic Belt is characterized by intense crustal deformation,well-developed active tectonics,and frequent occurrences of strong earthquakes.Therefore,conducting a Probabilistic ... The northern segment of the North-South Seismic Belt is characterized by intense crustal deformation,well-developed active tectonics,and frequent occurrences of strong earthquakes.Therefore,conducting a Probabilistic Seismic Hazard Analysis(PSHA)for this region is of significant importance for supporting seismic fortification in major engineering projects and formulating disaster prevention and mitigation policies.In this study,a composite seismic source model was constructed by integrating data on historical earthquakes,active faults,and paleoseismicity.Furthermore,a logic tree framework was employed to quantify epistemic uncertainties,enabling a systematic seismic hazard assessment of the region.To more accurately characterize the spatial heterogeneity of seismic activity,improvements were made to both the Circular Spatial Smoothing Model(CSSM)with a fixed radius and the Adaptive Spatial Smoothing Model(ASSM),with full consideration given to the spatiotemporal completeness of historical earthquake magnitudes.Regarding the CSSM,for scenarios involving small sample sizes in earthquake catalogs,the cross-validation method proposed in this study demonstrated higher robustness than the maximum likelihood method in determining the optimal correlation distance.Performance evaluation results indicate that while both models effectively characterize seismic activity,the ASSM exhibits superior overall predictive performance compared to the CSSM,owing to its ability to adaptively adjust the smoothing radius according to seismic density.Significant discrepancies were observed in the Peak Ground Acceleration(PGA)results calculated with a 10%probability of exceedance in 50 years across different combinations of seismic source models.The single spatially smoothed point-source model yielded a maximum PGA of approximately 0.52 g,with high-value areas concentrated near historical epicenters,thereby significantly underestimating the hazard associated with major fault zones.When combined with the simple fault-source model,the maximum PGA increased to 0.8 g,with high-value zones exhibiting a zonal distribution along faults;however,the risk remained underestimated for faults with low slip rates that are nevertheless approaching their recurrence cycles.Following the introduction of the time-dependent characteristic fault-source model,local PGA values for faults in the middle-to-late stages of their recurrence cycles increased by a factor of 2 to 7 compared to the single model.These results demonstrate that the characteristic fault-source model reasonably delineates the time-dependence of large earthquake recurrence,thereby providing a more accurate assessment of imminent seismic risks.By comprehensively applying the improved spatially smoothed pointsource model,the simple fault-source model,and the characteristic fault-source model,the following faults within the region were identified as having high seismic hazard:the Huangxianggou,Zhangxian,and Tianshui segments of the Xiqinling northern edge fault;the Maqin-Maqu segment of the Dongkunlun fault;the Longriqu fault;the Maoergai fault;the Elashan fault;the Riyueshan fault;the eastern segment of the Lenglongling fault;the Maxianshan segment of the Maxianshan northern Margin fault;and the Maomaoshan-Jinqianghe segment of the Laohushan-Maomaoshan fault.As these faults are located within seismic gaps or are approaching the recurrence periods of large earthquakes,they should be prioritized for current and future seismic monitoring as well as disaster prevention and mitigation efforts. 展开更多
关键词 northern segment of the north-South Seismic Belt fault-source characteristic earthquake spatial smoothing model
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晚期卵巢癌R0手术的个体化治疗
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作者 刘开江 《中国实用妇科与产科杂志》 北大核心 2026年第1期28-31,共4页
对于晚期卵巢癌肿瘤细胞减灭术达到R0切除,是改善晚期卵巢癌患者预后的最关键因素。手术能否达到R0主要取决3个因素:肿瘤扩散情况,患者身体状况和手术团队能力。R0切除是极其复杂并且需要多学科高度协作的系统工程,需要重视个体化治疗原... 对于晚期卵巢癌肿瘤细胞减灭术达到R0切除,是改善晚期卵巢癌患者预后的最关键因素。手术能否达到R0主要取决3个因素:肿瘤扩散情况,患者身体状况和手术团队能力。R0切除是极其复杂并且需要多学科高度协作的系统工程,需要重视个体化治疗原则,包括选择合适的手术时机,合理的手术方式,足够的手术范围才能达到满意的肿瘤细胞减灭术。 展开更多
关键词 卵巢癌 R0手术 个体化治疗
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多主体协同治理视域下0~3岁托育服务质量评价体系构建研究
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作者 刘岩 《科教文汇》 2026年第4期25-28,共4页
在人口结构转型与低生育率常态化的社会背景下,0~3岁婴幼儿托育服务既面临重要发展机遇,又遭遇多重治理挑战。当前托育服务质量评价体系存在评价维度碎片化、主体协同缺位等结构性缺陷,难以系统反映托育服务质量的整体状况。多主体协同... 在人口结构转型与低生育率常态化的社会背景下,0~3岁婴幼儿托育服务既面临重要发展机遇,又遭遇多重治理挑战。当前托育服务质量评价体系存在评价维度碎片化、主体协同缺位等结构性缺陷,难以系统反映托育服务质量的整体状况。多主体协同治理理论为解决这一困境提供了创新性的理论框架。本研究通过系统梳理协同治理理论的核心内涵,深入分析其在评价指标科学设定与评估流程优化中的理论价值,进而构建基于“结构—过程—结果”三维框架的多元协同评价体系,为实现“幼有所育、育有所质”的政策目标提供理论支撑和实践路径。 展开更多
关键词 多主体协同治理 0~3岁托育 服务质量 评价体系
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1971—2022年秦岭南北气温时空比较及气候分界变化
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作者 郝成元 杨铮 《信阳师范大学学报(自然科学版)》 2026年第1期26-35,共10页
以秦岭南北两侧各6个气象站为研究对象,基于1971—2022年逐日平均气温、最高气温及最低气温数据,采用趋势分析法与中值波动法,系统表征了该区域气温变化趋势及波动特征,主要结论如下:(1)秦岭山地整体气温呈显著递增趋势,北麓增温速率相... 以秦岭南北两侧各6个气象站为研究对象,基于1971—2022年逐日平均气温、最高气温及最低气温数据,采用趋势分析法与中值波动法,系统表征了该区域气温变化趋势及波动特征,主要结论如下:(1)秦岭山地整体气温呈显著递增趋势,北麓增温速率相对较快,南麓较慢;(2)春季增温幅度最大,秋季最小;(3)研究期内,所有月份的气温变化倾向率均为正值,且大部分表现为北麓高于南麓;(4)低温是秦岭山地气温分界效应变化的最主要指标,春季则是对区域增温贡献率最高的季节。伴随着全球气候加速增温,秦岭作为南北分界线的气温分界作用已呈现减弱趋势;(5)相较于其他月份,秦岭区域1月增温更为突出,尤其是1998年之后增温趋势显著。叠加上北麓增温快而南麓增温慢的空间差异,秦岭或将从传统的中国最冷月的0℃等温线转变为1℃等温线的南北分界。 展开更多
关键词 中国南北地理生态分界线 0℃等温线 全球变暖 春季气温变化
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YOLOv10-MTP:基于YOLOv10的自动驾驶多任务感知系统
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作者 金彦亮 孙龙武 《工业控制计算机》 2026年第2期68-69,72,共3页
自动驾驶系统的核心在于高效、准确地感知环境。现有的多任务感知框架在目标检测、车道线检测和可行驶区域分割等任务中虽然取得了很好的性能指标,但在实时性和复杂场景理解方面仍存在局限。为此,提出了一种新型多任务感知模型——YOLOv... 自动驾驶系统的核心在于高效、准确地感知环境。现有的多任务感知框架在目标检测、车道线检测和可行驶区域分割等任务中虽然取得了很好的性能指标,但在实时性和复杂场景理解方面仍存在局限。为此,提出了一种新型多任务感知模型——YOLOv10-MTP(YOLOv10 Multi-Task Perception)。该模型基于YOLOv10骨干网络,并进一步引入稀疏自注意力模块(Sparse Self-attention,SSA),有效提升了实时性。YOLOv10-MTP还引入了图像字幕任务,进一步预训练YOLOv10,以增强其对复杂驾驶场景的理解能力,从而提升下游任务(目标检测、车道线检测和可行驶区域分割)的性能。实验结果表明,在BDD100K数据集上,YOLOv10-MTP在嵌入式设备上实现了40 fps的实时推理,且在各项任务中均取得了优异表现,Recall和mAP50得分显著提升,展示了模型在复杂场景下的理解能力和有效性。 展开更多
关键词 自动驾驶 多任务感知 目标检测 实例分割 图像字幕
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糖足方治疗Wagner 0级糖尿病足的80例随机对照试验
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作者 陈泓 黄仁燕 +1 位作者 游洋 柳国斌 《时珍国医国药》 北大核心 2026年第4期691-697,共7页
目的观察糖足方治疗Wagner 0级糖尿病高危足的临床疗效及安全性。方法将172例糖尿病高危足患者随机分为观察组和对照组各86例。两组均给予常规治疗及护理,对照组予以甲钴胺片联合阿司匹林肠溶片治疗,观察组予糖足方口服结合足浴疗法,两... 目的观察糖足方治疗Wagner 0级糖尿病高危足的临床疗效及安全性。方法将172例糖尿病高危足患者随机分为观察组和对照组各86例。两组均给予常规治疗及护理,对照组予以甲钴胺片联合阿司匹林肠溶片治疗,观察组予糖足方口服结合足浴疗法,两组疗程均为6个月,并随访6个月。比较两组的临床疗效、溃疡发生率,治疗前后中医症候评分、下肢动脉彩色超声评分、多伦多临床评分(TCSS)、密歇根评分(MNSI)、和神经传导速度测试(NCV)[运动神经传导速度(MNCV);感觉神经传导速度(SNCV)]。比较治疗前后肝肾功能及不良反应发生情况。结果最终共有各80例患者完成研究并纳入分析。治疗12个月后,观察组总有效率为95.00%,显著高于对照组85.00%(P<0.05);足溃疡发生率,观察组为5.00%,对照组为11.25%,差异无统计学意义(P>0.05);与本组治疗前比较,两组中医证候评分、TCSS评分、MNSI评分均明显降低(P<0.05),且治疗后观察组各指标改善均优于对照组(P<0.05);观察组动脉硬化评分治疗后较前明显降低,且低于对照组,差异有统计学意义(P<0.05),对照组治疗前后差异无统计学意义(P>0.05);两组治疗前后内膜厚度和血管狭窄评分差异均无统计学意义(P>0.05)。治疗期间,两组均未出现明显不良反应,肝肾功能指标稳定。结论糖足方在治疗Wanger 0级糖尿病足患者中具有良好临床疗效,能显著改善症状、降低足溃疡发生率、提升神经传导功能,且安全性良好,值得临床推广应用。 展开更多
关键词 糖足方 Wagner 0 糖尿病高危足 足溃疡 足浴疗法
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沿面介质阻挡放电协同催化剂脱除NO/SO_(2)/Hg^(0)实验研究
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作者 李朝兵 杨泽勇 +4 位作者 胡德浩 宋捷 赖金平 米高丽 于洁 《动力工程学报》 北大核心 2025年第2期292-299,共8页
通过选取并制备纳米TiO_(2)、Mn-TiO_(2)和Mn-Ce-TiO_(2)3种催化剂,研究了不同反应温度、烟气中氧体积分数以及气体停留时间条件下,各催化剂对NO、SO_(2)及Hg^(0)_(3)种污染物的催化氧化性能;分析了低温等离子体条件下,不同催化剂对NO、... 通过选取并制备纳米TiO_(2)、Mn-TiO_(2)和Mn-Ce-TiO_(2)3种催化剂,研究了不同反应温度、烟气中氧体积分数以及气体停留时间条件下,各催化剂对NO、SO_(2)及Hg^(0)_(3)种污染物的催化氧化性能;分析了低温等离子体条件下,不同催化剂对NO、SO_(2)及Hg^(0)的氧化机制。结果表明:反应温度升高能够促进NO、SO_(2)及Hg^(0)的氧化转化;增加反应气在催化反应器中的停留时间同样可以促进上述污染物的转化,但停留时间过长会引发副反应;在不同氧化还原气氛下,NO、SO_(2)及Hg^(0)表现的催化脱除机理不同;相比于TiO_(2)和Mn-TiO_(2)催化剂,Mn-Ce-TiO_(2)催化剂对NO、SO_(2)及Hg^(0)的脱除效果最优;相比于单独使用沿面型介质阻挡放电和催化剂,两者之间的耦合能够更好地脱除NO、SO_(2)及Hg^(0),并且协同Mn-Ce-TiO_(2)催化剂具有最优的污染物脱除性能。 展开更多
关键词 沿面介质阻挡放电 催化剂 催化氧化 no SO_(2) Hg^(0)
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基于改进EfficientNet-B0的轻量化苹果叶病害识别 被引量:1
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作者 王新皓 苏淑靖 +1 位作者 翟聪 文若铭 《农机化研究》 北大核心 2026年第3期137-144,共8页
为了对苹果叶片病害进行精准有效识别,提出了一种基于改进EfficientNet-B0的轻量级高精度识别模型——LC-EfficientNet。首先,在MBConv模块中引入无参数注意力模块SimAM,提高识别能力的同时不增加模型计算量;其次,结合ShuffleNetV2双分... 为了对苹果叶片病害进行精准有效识别,提出了一种基于改进EfficientNet-B0的轻量级高精度识别模型——LC-EfficientNet。首先,在MBConv模块中引入无参数注意力模块SimAM,提高识别能力的同时不增加模型计算量;其次,结合ShuffleNetV2双分支结构思想与MBConv生成改进模块HPRConv,充分利用双分支结构,使用深度可分离卷积后,引入通道混洗技术与通道拼接技术,显著减少计算量和参数量且提升了模型对不同层次特征的提取能力;最后,将激活函数由Swith换为Mish,以帮助模型更好地拟合数据,提升准确率。使用模型分别对PlantVillage和Appleleaf9苹果叶部病害数据集进行训练与测试实验,结果表明LC-EfficientNet模型在两个数据集上的分类准确率分别达到98.83%和94.67%,相较于原模型分别提升了1.11和2.26个百分点,参数量从5.3 MB左右降低到4.5 MB左右,在降低参数量的同时增加了准确率;与其他经典网络模型相比,LC-EfficientNet在各项性能评估指标上也均有所提升。研究可为苹果叶部病害识别提供新的解决方案。 展开更多
关键词 苹果叶 病害识别 卷积神经网络 轻量级 EfficientNet-B0 SimAM注意力模块 图像处理技术
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Evaluation of Agronomic Traits in Chromosome Segment Substitution Lines of KDML105 Containing Drought Tolerance QTL under Drought Stress 被引量:1
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作者 Vaiphot KANJOO Kanchana PUNYAWAEW +3 位作者 Jonaliza L.SIANGLIW Suwat JEARAKONGMAN Apichart VANAVICHIT Theerayut TOOJINDA 《Rice science》 SCIE 2012年第2期117-124,共8页
Drought is a major abiotic constraint to rice production in rainfed lowland and insufficiently irrigated areas. The improvement of drought tolerant varieties is one of the strategies to reduce the negative effects of ... Drought is a major abiotic constraint to rice production in rainfed lowland and insufficiently irrigated areas. The improvement of drought tolerant varieties is one of the strategies to reduce the negative effects of drought. Quantitative trait loci (QTLs) for primary and secondary traits related to drought tolerance (DT) on chromosomes 1, 3, 4, 8 and 9 that determined from double haploid lines derived from a cross between CT9993 and IR62266 were introgressed and dissected into small pieces in the genetic background of Khao Dawk Mall 105 (KDML105) to develop chromosome segment substitution line (CSSL) population. The CSSLs were evaluated at the reproductive stage for their agronomic performance and yield components under drought stress, and results were compared with irrigated condition. The flowering of CSSL lines was 6 to 7 d earlier than KDML105. The mean values of grain yields in the CSSLs were higher than KDML105 under drought and irrigated conditions. At irrigated condition, the grain yields of introgression lines carrying DT-QTLs from chromosomes 4 and 8 were higher than that of KDML105, whereas other traits showed little difference with KDML105. Analysis indicated that grain yield has positive correlation with plant height, tiller and panicle number per plant, and total grain weight per plant under drought stress while negatively correlated with days to flowering. As mentioned above, CSSLs showing good adaptation under drought stress can be used as genetic materials to improve drought tolerance in Thai rainfed lowland rice breeding program, and as materials to dissect genes underlying drought tolerance. 展开更多
关键词 chromosome segment substitution lines drought tolerance quantitative trait loci drought stress Jasmine rice
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广西防城港地区0~3岁儿童生长发育状况及营养不良影响因素分析
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作者 陈雪 江蕙芸 +2 位作者 蔡始景 吴薇岚 丘小霞 《教育生物学杂志》 2026年第1期23-28,共6页
目的 调查广西防城港地区0~3岁儿童的生长发育状况,分析营养不良的影响因素,为制定针对性干预措施提供依据。方法 采用随机抽样法,选取在该地区基层卫生机构参与定期体检且已建立健康档案的0~3岁儿童为研究对象,共纳入2 660名,最终获得... 目的 调查广西防城港地区0~3岁儿童的生长发育状况,分析营养不良的影响因素,为制定针对性干预措施提供依据。方法 采用随机抽样法,选取在该地区基层卫生机构参与定期体检且已建立健康档案的0~3岁儿童为研究对象,共纳入2 660名,最终获得有效数据2 429份。通过体格测量与问卷调查(涵盖一般人口学特征、家庭养育情况、儿童出生健康史及早期喂养情况)收集数据,运用Z评分法评估儿童生长水平与营养状况,采用Logistic回归分析营养不良的影响因素。结果 防城港地区0~3岁儿童生长状况各Z评分指标中位数均为负值,低体质量率、消瘦率及生长迟缓率分别为6.9%、9.7%和10.5%。Logistic回归分析显示:母亲非汉族(OR=1.848)、儿童低出生体质量(OR=3.920)是儿童低体质量的独立影响因素;家庭居住地为乡村(OR=1.404)、儿童低出生体质量(OR=2.292)是儿童消瘦的影响因素;母亲非汉族(OR=1.380)、受教育程度低(OR=1.517)及儿童低出生体质量(OR=3.397)是儿童生长迟缓的影响因素。结论 广西防城港地区0~3岁儿童的生长发育与营养状况亟待改善。建议强化孕产期健康宣教工作,以降低新生儿低出生体质量率;同时,重点针对母亲为非汉族、居住地位于乡村及母亲受教育程度较低的家庭,开展儿童生长发育动态监测与科学喂养专项指导。 展开更多
关键词 生长发育 Z评分法 营养不良 0~3岁儿童
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Upper crustal azimuthal anisotropy and seismogenic tectonics of the Hefei segment of the Tan-Lu Fault Zone from ambient noise tomography 被引量:1
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作者 Cheng Li HuaJianYao +4 位作者 Song Luo HaiJiang Zhang LingLi Li XiaoLi Wang ShengJun Ni 《Earth and Planetary Physics》 2025年第2期253-265,共13页
The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structur... The Tan-Lu Fault Zone is a large NNE-trending fault zone that has a substantial effect on the development of eastern China and its earthquake disaster prevention efforts. Aiming at the azimuthally anisotropic structure in the upper crust and seismogenic tectonics in the Hefei segment of this fault, we collected phase velocity dispersion data of fundamental mode Rayleigh waves from ambient noise cross-correlation functions of ~400 temporal seismographs in an area of approximately 80 × 70 km along the fault zone. The period band of the dispersion data was ~0.5–10 s. We inverted for the upper crustal three-dimensional(3-D) shear velocity model with azimuthal anisotropy from the surface to 10 km depth by using a 3-D direct azimuthal anisotropy inversion method. The inversion result shows the spatial distribution characteristics of the tectonic units in the upper crust. Additionally, the deformation of the Tan-Lu Fault Zone and its conjugated fault systems could be inferred from the anisotropy model. In particular, the faults that have remained active from the early and middle Pleistocene control the anisotropic characteristics of the upper crustal structure in this area. The direction of fast axes near the fault zone area in the upper crust is consistent with the strike of the faults, whereas for the region far away from the fault zone, the direction of fast axes is consistent with the direction of the regional principal stress caused by plate movement. Combined with the azimuthal anisotropy models in the deep crust and uppermost mantle from the surface wave and Pn wave, the different anisotropic patterns caused by the Tan-Lu Fault Zone and its conjugated fault system nearby are shown in the upper and lower crust. Furthermore,by using the double-difference method, we relocated the Lujiang earthquake series, which contained 32 earthquakes with a depth shallower than 10 km. Both the Vs model and earthquake relocation results indicate that earthquakes mostly occurred in the vicinity of structural boundaries with fractured media, with high-level development of cracks and small-scale faults jammed between more rigid areas. 展开更多
关键词 ambient noise tomography azimuthal anisotropy upper crust seismogenic structure the Tan-Lu Fault Zone Hefei segment
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基于ET_(0)预报方法的单日与累积ET_(0)预报比较研究
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作者 颜秉钧 罗玉峰 +5 位作者 徐阳 张卓 章策 崔远来 陈梦婷 胡旭铧 《中国农村水利水电》 北大核心 2026年第2期194-199,共6页
为探究不同预见期下累积参考作物腾发量(ET_(0))预报精度的变化规律,优化农业灌溉管理中的ET_(0)预测方法,以内蒙古绰勒灌区扎赉特旗站为研究对象,基于逐日天气预报数据与同期实测气象数据,采用Hargreaves-Samani(HS)模型与FAO Penman-M... 为探究不同预见期下累积参考作物腾发量(ET_(0))预报精度的变化规律,优化农业灌溉管理中的ET_(0)预测方法,以内蒙古绰勒灌区扎赉特旗站为研究对象,基于逐日天气预报数据与同期实测气象数据,采用Hargreaves-Samani(HS)模型与FAO Penman-Monteith(PM)公式,系统分析了1~7 d预见期内单日ET_(0)预报与累积ET_(0)预报的精度差异及其随预见期延长的动态变化特征。研究以PM公式计算结果为基准值,通过对比HS模型在不同预见期下的拟合度(R^(2))、平均绝对误差(MAE)及误差分布特征,明确了累积预报的优势及最优预见期。研究结果表明:(1)单日ET_(0)预报的R^(2)均值为0.89,MAE均值为0.36 mm/d,最大单日误差达0.40 mm/d,表明单日预报存在显著的不确定性;(2)累积ET_(0)预报精度显著优于单日预报,所有预见期(1~7 d)的R^(2)均提升至0.92以上,且MAE随累积天数的增加呈稳步下降趋势。具体而言,1~7 d累积预报的MAE均值分别为0.32、0.30、0.40、0.29、0.21、0.24、0.23 mm/d,其中7 d累积预报的MAE最低(0.23 mm/d),较单日预报误差降低36.1%,且误差波动范围显著收敛;(3)累积预见期延长至7 d时,误差累积效应被有效平滑,气象要素短期波动的负面影响减弱,模型系统性偏差得到抑制,预报稳定性显著增强。综上,研究揭示了累积ET_(0)预报精度随预见期延长的提升规律,并验证了7 d为最优累积预见期。研究成果可为灌区动态灌溉计划的制定提供理论依据,尤其在数据驱动型农业水资源管理中,采用7 d累积ET_(0)预报可显著提升灌溉预报的可靠性与实用性。未来研究可进一步结合数值天气预报模型,探索多尺度ET_(0)预报的耦合优化方法。 展开更多
关键词 参考作物腾发量 参考作物腾发量预报 累积ET_(0)
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Successful emergency surgical intervention in acute non-STsegment elevation myocardial infarction with rupture:A case report
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作者 Xing-Po Li Zi-Shan Wang +1 位作者 Hong-Xia Yu Shan-Shan Wang 《World Journal of Clinical Cases》 SCIE 2025年第4期41-47,共7页
BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular ... BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular free wall rupture(FWR)occurs in approximately 2%of AMI patients and is notably rare in patients with non-STEMI.Types of cardiac rupture include left ventricular FWR,ventricular septal rupture,and papillary muscle rupture.The FWR usually leads to acute cardiac tamponade or electromechanical dissociation,where standard resuscitation efforts may not be effective.Ventricular septal rupture and papillary muscle rupture often result in refractory heart failure,with mortality rates over 50%,even with surgical or percutaneous repair options.CASE SUMMARY We present a rare case of an acute non-STEMI patient who suffered sudden FWR causing cardiac tamponade and loss of consciousness immediate before undergoing coronary angiography.Prompt resuscitation and emergency open-heart repair along with coronary artery bypass grafting resulted in successful patient recovery.CONCLUSION This case emphasizes the risks of AMI complications,shares a successful treatment scenario,and discusses measures to prevent such complications. 展开更多
关键词 Acute non-ST segment elevation myocardial infarction Cardiac rupture Acute myocardial infarction Free wall rupture Case report
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Panoramic Glass Image Segmentation Network
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作者 Guanlin Pan Yan Cui +3 位作者 Qingling Chang Kelin Li Yangtao Ou Haohui Yu 《Journal of Electronic Research and Application》 2025年第6期105-112,共8页
In panoramic images,the geometric distortion caused by wide-angle lenses makes traditional semantic segmentation methods difficult to accurately segment the glass areas.To address the challenges of capturing spatial f... In panoramic images,the geometric distortion caused by wide-angle lenses makes traditional semantic segmentation methods difficult to accurately segment the glass areas.To address the challenges of capturing spatial features and integrating context information,we propose the Panoramic Glass Image Segmentation Network(PGISNet).This network integrates the Matrix Decomposition Base Module(MDBM),the Transparent Perception Consistency Module(TACM),the Context and Texture Compensation Module(CTCM),and the Multi-scale Gated Context Attention Module(MGCA),constructing a progressive feature processing flow.Experimental results on the PanoGlassV2 benchmark test show that PGISNet achieved 90.03%IoU,94.76%F-score,and 94.0%PA,significantly outperforming existing methods,verifying its effectiveness and advancement in the panoramic image glass segmentation task. 展开更多
关键词 Glass segmentation Machine learning Panoramic segmentation
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